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Home My WebLink About2026/07/28 - Revised Stormwater Management Report - 492 Sutton Street Iffll((((((((�(�(((((((((fI111111U1111D)JIJJJJJ McC L U R ETNA Stormwater 14anagement IHH� Lawrence Municipal Airport Administration Building 492 Sutton Street, North Andover, MA Preparedoouuu r Lawrence Municipal Airport 492 Sutton Street, North Andover, MA Prepared o y. McClure Engineering Company 225 Friend Street,Suite 805, Boston, MA June 16,2026 Revised July 28,2026 225 Friend Street,Sufte 805, Eloston, Massachusetts N N o0 . 1 Project Overview...............................................................................................................................................3 1.1 Existing Site Conditions.......................................................................................................................... 3 1.2 Proposed Development and Stormwater Management System............................................................4 2 Stormwater Runoff Analysis.............................................................................................................................5 2.1 Methodology.......................................................................................................................................... 5 2.2 Watershed Delineation Existing Conditions ...................................................................................... 6 2.3 Watershed Delineation Proposed Conditions................................................................................... 6 2.4 Peak Runoff Results............................................................................................................................... 7 2.5 Runoff Volume Results.......................................................................................................................... 8 3 Erosion,Sediment,and Pollution Controls.......................................................................................................9 4 Regulatory Compliance.....................................................................................................................................9 4.1 Massachusetts Stormwater Handbook Compliance.............................................................................. 9 4.2 Local Bylaw Compliance...................................................................................................................... 12 5 Conclusions....................................................................................................................................................16 Figures Figure 1 —Site Location Map Figure 2—Resource Area Map Figure 3—USGS Topographic Map Figure 4—FEMA Flood Insurance Rate Map Figure 5—Pre-Development Watershed Map Figure 6—Post-Development Watershed Map Appendices Appendix A—Site Plans(Separately Bound) Appendix B—NRCS Soil Survey Report Appendix C—Subsurface Investigation Logs Appendix D—Pre-Development HydroCAD Report Appendix E— Post-Development HydroCAD Report Appendix F— MassDEP Stormwater Checklist Appendix G—BMP Design Calculations Appendix H - TSS Removal Calculations Appendix I— Long-Term Operation and Maintenance Plan Appendix J— Illicit Discharge Statement Appendix K—Groundwater Mounding Analysis Appendix L—Treatment Device Documentation Stormwater Report—LWM Administration Building—492 Sutton Street Page 2 IIIII°� "'"" IIIr IIIIII The Lawrence Municipal Airport Commission proposes to demolish the existing 1950s-era Administration Building at Lawrence Municipal Airport (LWM) and construct a new one-story Administration Building with associated site improvements at 492 Sutton Street, North Andover, Massachusetts. The project involves construction of the 7,000+/- square foot building, reconstruction of a portion of the existing paved parking lot for improved site circulation,new and/or relocated underground utilities,grading,stormwater management,and construction-period erosion controls. The proposed stormwater management system has been designed in accordance with the Massachusetts Department of Environmental Protection Stormwater Handbook and the Town of North Andover Stormwater Management and Erosion Control Regulations (Chapter 250) under Chapter 165 of the Town Bylaws.The system has been designed to limit increases in peak runoff rates, provide stormwater treatment, and promote recharge to the extent feasible. The project is a redevelopment of existing developed areas and is considered a combination of Redevelopment and New Development,with an increase in impervious area of approximately 7,360 square feet. 1.1 Existing Site Conditions The project is located at 492 Sutton Street within the Lawrence Municipal Airport (LWM) campus. The overall property exceeds 400 acres and is substantially developed with airport infrastructure, hangars, parking facilities, and buildings supporting a range of commercial uses. The project area is limited to the existing Administration Building and its adjacent parking lot at the end of Terminal Road,the primary access drive from Sutton Street. See Figure 1 for the Site Location Map. The project area encompasses the Administration Building and the adjacent parking lot to be reconstructed. Stormwater runoff drains generally from southeast to northwest across the site, from the parking lot toward the Administration Building and the active airfield to the west and north.The project area represents the low point of the developed landside area. All runoff from the project limits, as well as adjacent parking areas and Terminal Road, ultimately converges at a single catch basin on the airfield side of the Administration Building before being conveyed through the existing closed drainage system across the airfield. Therefore, the project area contains multiple drainage systems flowing through its limits and also receives overland flow from non-project areas through the project limits.This offsite runoff traverses the existing parking lot,where it is captured by existing catch basins and enters the closed drainage system along with on-site runoff. No work is proposed within the active airfield area. Ultimately, stormwater is discharged within the lawn areas west of the airfield and finally to existing downstream wetlands on the property. There are no stormwater management facilities within the project limits.The existing closed drainage infrastructure consists of connected inline catch basins and generally shallow piping, conveying the runoff to a discharge point outside of the project area. There are no wetland resource areas within proximity to the project site. According to the Natural Heritage and Endangered Species Program (NHESP), the project site is not located within mapped Priority Habitats of Rare Species, Estimated Habitats of Rare Wildlife, or Areas of Critical Environmental Concern (ACEC), as shown on the Resource Area Map in Figure 2. Per Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM) Panel Number 25009CO228G,dated July 8,2025 the site is not located within a Special Flood Hazard Area. The FIRM is included in Figure 4. Stormwater Report—LWM Administration Building—492 Sutton Street Page 3 According to the USDA Natural Resources Conservation Service (NRCS) Web Soil Survey, the project site is predominantly mapped as Urban Land (Map Unit 602), with portions mapped as Paxton fine sandy loam, 3 to 8 percent slopes(Map Unit 305B, Hydrologic Soil Group C).The NRCS Soil Report is included in Appendix B. Subsurface soil conditions were evaluated through geotechnical borings and installation of monitoring wells within the project limits. The investigation revealed a consistent profile: a surficial topsoil or asphalt layer extending to approximately 0.3 to 0.9 feet below ground surface(bgs),underlain by historical granular fill to approximately 2 to 6 feet bgs (Hydrologic Soil Group C), and a natural glacial outwash sand stratum below (Hydrologic Soil Group A). Groundwater was observed in monitoring wells at depths ranging from 3.5 to 8.1 feet bgs across the project limits, with depths of 3.5 to 5.0 feet bgs in the vicinity of the proposed stormwater BMPs. Physical test pits performed by others(Hancock Associates)on the property in connection with an adjacent project documented soil mottling at approximately 38 inches (3.2 feet) below existing grade. This mottling-based determination is considered more representative of the ESHGW than the stabilized monitoring well readings,which reflect current water table conditions rather than the historical seasonal high.Accordingly, ESHGW is established at 3.2 feet below existing ground surface for stormwater design purposes. For hydrologic modeling purposes,soils are classified as Hydrologic Soil Group C,with a design infiltration rate of 0.27 inches per hour per the Rawls rate for the applicable soil texture class(Massachusetts Stormwater Handbook Vol.2,Table 2-4).Subsurface investigation results are included in Appendix C. 1.2 Proposed Development and Stormwater Management System The proposed improvements result in a net increase of approximately 7,400 square feet of impervious area,with approximately 28,600 square feet of total post-construction impervious area within the project limits. The stormwater management system has been designed to control peak discharge rates and provide water quality treatment and recharge to the extent feasible.The following best management practices(BMPs)are proposed: • BMP 1 Stormwater Basin • BMP 2 Vegetated Detention Areas • BMP 3 Manufactured Cartridge Filtration Unit(Jellyfish or equivalent) BMP 1:Stormwater Basin(1 proposed) A shallow stormwater basin is proposed along the eastern limit of the project to intercept overland runoff from offsite areas east of the project which flow into the parking lot. Under existing conditions,this runoff traverses the parking lot surface unimpeded,accumulating sediment and surface pollutants before entering the closed drainage system.The proposed basin captures this flow upstream of the parking lot and provides peak flow attenuation and groundwater recharge.The basin is designed with two outlets:a stabilized berm overflow that directs retained runoff to the parking lot at the same location where offsite flow currently discharges under existing conditions, and an outlet control structure connecting to the existing closed drainage system.The basin is sized to infiltrate stormwater at the design infiltration rate of 0.27 inches per hour. While this basin does not receive runoff from impervious areas, it does intercept runoff which would ultimatelyflow over impervious areas,transporting sediments downstream and contributing to peak flows. Based on the constraints within the redevelopment area,this is a best effort proposal to incorporate low impact development and recharge into the project area. BMP 2:Vegetated Detention Area Two (2)vegetated detention areas are proposed within the primary parking lot island. The parking lot island is the only developable open space within the project limits.This low-impact design feature provides provide peak flow mitigation, treatment, and recharge to the extent feasible. Runoff from the parking lot is directed through pretreatment units(Rain Guardian Turrets or equivalent)prior to discharge into the vegetated detention areas,where stormwater is retained until overflowing through an outlet control structure to the existing closed drainage system. Stormwater Report—LWM Administration Building—492 Sutton Street Page 4 Because of the constrained site footprint and its location at the low point of the drainage area, there are limited opportunities to capture proposed impervious areas in low impact stormwater BMPs.The vegetated detention area is proposed for this reason,and provides surface storage volume,promotes groundwater recharge to the maximum extent practicable, and contributes to the low-impact development requirements of North Andover Chapter 250 §250-23A(1). Manufactured Cartridge Filtration Unit A Contech Jellyfish unit(or equivalent)is proposed downstream of the parking lot drainage collection system.Runoff from approximately 23,024 square feet(0.52 acres) of impervious area is conveyed through the filtration unit prior to discharge, providing TSS and phosphorus removal in accordance with Massachusetts Stormwater Standard 4 and the water quality performance standards of North Andover Chapter 250§250-23B(1).The unit is sized to treat the required water quality volume for its contributing drainage area and internally bypass flow from larger storms. Performance data and sizing calculations are included in Appendix L. Pretreatment includes one or a combination of the following depending on the treatment train and location of impervious: - Deep sump hooded catch basins - Rain Guardian Turret pretreatment inlet - Vegetated Filter Strip(lawn areas) Downstream of the stormwater management BMPs,treated stormwater is conveyed to the existing closed drainage system network,consistent with the existing drainage patterns on site. Regulatory compliance for each BMP is documented in Section 5 of this report. Stariimwateir IRuirioffIIIII IIIIII 2.1 Methodology Hydrologic modeling for pre- and post-development conditions was performed using HydroCAD Stormwater Modeling Software. The model applies the NRCS TR-20 methodology with cumulative rainfall-volume dependent routing to generate peak runoff rates and total runoff volumes for each watershed catchment area.Hydrographs are developed for individual subcatchments and routed through the storage-indication method to evaluate BMP performance and downstream discharge conditions. Rainfall depths for 24-hour storm events were obtained from NOAA Atlas 14,Volume 10. Four design storms were analyzed:the 2-, 10-2 25-,and 100-year return periods. Curve numbers for each subcatchment were developed based on land cover type and Hydrologic Soil Group C. A minimum Time of concentration(Tc)of 6 minutes was used,unless calculated Tc exceeded the 6 minute minimum, in which case the actual Tc was utilized, with a maximum sheet flow length of 50 feet. Groundcover modeling assumptions are as follows: • Existing and proposed impervious surfaces,including rooftops,asphalt pavement,and concrete sidewalks, were modeled using a curve number of 98. • Gravel roads were modeled using a curve number of 89(HSG C). • Offsite pervious areas contributing overland flow to the project site were modeled in good condition, regardless of current condition of woods, lawn,and open space. Stormwater Report—LWM Administration Building—492 Sutton Street Page 5 The watershed analysis includes all upgradient areas contributing runoff to the project site, including the drainage area to the east that flows overland onto the project site under existing conditions. Two(2)design points were established for the pre-and post-development analysis: • Design Point 1 (DP-1) Existing Airfield Catch Basin/Junction Structure • Design Point 2(DP-2) Overland Flow towards airfield The pre-development hydrologic model is included in Appendix D. The post-development hydrologic model is included in Appendix E. Pre-and Post-Development Watershed Maps are included in Figures 5 and 6. 2.2 Watershed Delineation—Existing Conditions The pre-development watershed encompasses 3.71 acres of the LWM airport campus, including the building roof, paved parking lot areas, and upgradient areas which contribute runoff over the site. In general, runoff from the easterly high point flows over undeveloped wooded area and grassed lawn areas before flowing overland into the existing parking lot area. Included in this runoff area are impervious areas associated with the electrical vault, control tower,and adjacent parking areas,none of which are proposed for redevelopment. Runoff from the majority of existing subcatchments discharges directly to existing inline catch basins in the parking lot which collect and convey runoff toward the airfield via the closed drainage system. This flow is analyzed at Design Point 1 (DP-1). Runoff from the subcatchments EX-4.2 and EX-5 flow overland,out of the project area to the north/west toward the airfield. This includes the grass and concrete pads around the building, as well as a portion of the building's roof. The overland flow toward the airfield is analyzed at Design Point 2(DP-2). Pre-development subcatchment boundaries and design points are shown on the Pre-Development Watershed Map (Figure 5).The complete pre-development hydrologic model is included in Appendix D. 2.3 Watershed Delineation—Proposed Conditions The post-development watershed encompasses 3.71 acres - the same analysis area as the pre-development model, re-delineated to reflect proposed grading and BMP routing. Overall drainage patterns are maintained,with the majority of stormwater analyzed at DP-1 (Existing Catch Basin),downstream of the project area. In the post-development condition, 0.84 acres of the offsite contributary runoff is collected in a shall stormwater basin within existing lawn area to mitigate peak flows and promote stormwater recharge.This includes 1,592 square feet of impervious associated with a gravel drive and pavement areas. The remainder of the offsite runoff that doesn't enter the basin mimics the existing drainage patterns,flowing overland to the existing paved parking areas. Runoff from 0.20 acres (8,799 sf) of paved parking lot, plus overflow from the stormwater basin is directed to Rain Guardian Turret units which discharge to Vegetated Detention Areas within the parking island. Stormwater overflows from the Vegetated Detention Areas via outlet control structures,which convey the overflow to the closed drainage system. A Contech Jellyfish membrane filtration unit(or equal)is proposed within the parking lot closed drainage system to provide treatment through filtration for runoff from the reconstructed parking lot area. The unit provides enhanced TSS and Total Phosphorus Removal. Only one (1) proposed subcatchment area, PR-5.1, discharges to DP-2 (Offsite Runoff over Airfield). The subcatchment area includes the grass and concrete areas located between the proposed building and the existing airfield,matching existing drainage patterns. Post-development subcatchment boundaries are shown on the Post-Development Drainage Map(Figure 5). Stormwater Report—LWM Administration Building—492 Sutton Street Page 6 2.4 Peak Runoff Results Pre-ondpoot-dovoioprnentpeohflovvrot000teonhdoo' point are summarized below for each design storm. The complete HydroCAD model io included in the Appendix. F._. Net Chan1ge, 110-YEAR,DESIGN STORM FLOWS 100-YEAR,DESIGN STORM FLOAWS |noii storms,there ioo reduction in net peak flows leaving the site. |n the 2-year design storm,there iooslight increase atDP-1 ofO.5%orO.O3ofo. However,the net change is a reduction in flow of 2.20%in the 2-year storm. In the 100-yaar storm event,there is o 0.48 ofe inonsaoa in flow(2.25;6)at OP-1' but on overall net deonaooe in flow leaving the site. In summary,the overall project results in a net decrease to downstream receiving waters. suormwmter Report—uwM Administration Building—4eo Sutton Street Page 2.5 Runoff Volume Results Pre-and post-development peak volumes ot each design point are summarized below for each design storm. The only increase in runoff volume is in the 1 00-year storm event at DP-1,which results in a 0.015 ac-ft(653 cf) increase,or 0.88%increase over existing conditions. This increase is due to the constraints related to groundwater recharge on site,which io explained in this report. |t should ba noted that the net runoff volume ofthe combined design points ioon overall reduction. suormwatar Report—uwM Administration Building—4e2 Sutton Street Page "' IIIIII IIIIII IIIIII IIIIII IIIII Illnl "" air id "'""IIIIII Illll i IIIIII"""IIIIII Erosion and sediment control measures will be installed prior to land disturbance and maintained through the completion of construction and permanent stabilization of all disturbed areas, in accordance with the Massachusetts Erosion and Sediment Control Guidelines for Urban and Suburban Areas. Details and notes are provided on the site plans. Proposed erosion and sediment controls include a stabilized construction entrance, compost filter tubes along the perimeter of disturbed areas,protection of proposed BMP areas,stockpile protection,and silt sack inlet protection. Additional controls will be implemented as warranted by field conditions. All perimeter controls will be installed down-gradient of disturbed areas prior to the start of grading. The total proposed land disturbance area (including contractor laydown areas)is approximately 59,300 square feet (1.36 acres), triggering the EPA NPDES General Permit for Discharge from Construction Activities. Accordingly, a Stormwater Pollution Prevention Plan (SWPPP)is required to be prepared for the project prior to land disturbance. Construction vehicle fueling and equipment staging will be confined within the limit of work.All construction waste and excavated materials will be removed from the site and disposed of at an approved facility.Temporary stockpile locations will be situated within the limit of work and protected with perimeter sediment controls. A construction sequencing plan is provided on the site plans. The sequence may be adjusted based on field conditions or other circumstances encountered during construction. "'"" IIIIII IIIII IIIIII IIIII The following describes how the proposed project complies with the Massachusetts Stormwater Management Standards as set forth in the Massachusetts Stormwater Handbook.The completed Massachusetts Stormwater Management Checklist is included in Appendix F. 4.1 Massachusetts Stormwater Handbook Compliance Standard 1 —No Untreated Discharge to Wetlands or Waterways No wetland resource areas as defined under MGL c. 131,§40 or the North Andover Wetlands Protection Bylaw (Chapter 190)are present within or adjacent to the project limits. No concentrated, untreated stormwater discharges to wetland resource areas or waterways are proposed. Standard 2 Peak Rate Attenuation Post-development net peak discharge rates from the project area are at or below pre-development rates for the 2-, 10-,and 25-year storm events. Peak flow attenuation is achieved through storage provided by the Stormwater Basin,which intercepts and detains offsite runoff before controlled release to the existing closed drainage system. Additional peak flow attenuation is provided through the Vegetated Detention Areas in the parking lot islands. There is a minimal increase in peak flows in the 2-and 100-year storm event of 0.03 and 0.51 cfs to one design point, DP-1. However,consideration of both analysis points results in a net decrease of peak flows from the project. Peak flow results are summarized in Section 2.4 of this report. Stormwater Report—LWM Administration Building—492 Sutton Street Page 9 Standard 3 Groundwater Recharge Standard 3 requires that annual recharge from post-development conditions mimic pre-development recharge volumes. The calculated recharge volume requirement for the new development impervious area (7,360 sf)with HSG C soils is 154 cubic feet. Recharge Volume provided by the two Vegetated Detention Areas totals 211 cubic feet,with 8,799 sf of contributing impervious areas. An additional 2,835 cf of recharge volume is provided in the Stormwater Basin,for a combined total of 3,046 cf of recharge volume provided by the stormwater management measures proposed in this project. The site presents constraints that limit the opportunity to provide additional recharge through conventional means. The shallow Estimated Seasonal High Groundwater elevation limits infiltration practice depth to a surficial configuration. Conveying parking lot runoff to undeveloped areas for recharge is impractical as the discharge elevation would be within groundwater. Prior projects on the property, located within undeveloped areas,achieved groundwater separation for recharge by raising the elevation of the project site by several feet. Raising the site to achieve groundwater separation is not feasible for this redevelopment project given the impacts to adjacent facilities and airport infrastructure surrounding the site. The proposed recharge facilities provide an improvement in site hydrology over existing conditions and provides peak flow mitigation.Groundwater recharge calculations and drawdown analysis are included in Appendix G. Standard 4 Water Quality Standard 4 requires a minimum of80%average annual TSS removal from the new impervious area.The required water quality volume is calculated to be 307 cubic feet. The Manufactured Filtration Unit(Jellyfish)provides the Water Quality compliance based on TSS Removal. The water quality volume provided by the Vegetated Detention Areas is limited to 212 cubic feet. Water quality treatment for impervious area runoff is provided through a treatment train consisting of the Rain Guardian pretreatment units and vegetated detention areas,deep sump hooded catch basins,and the cartridge filtration unit.The proposed TSS Removal averages at 87.9%for impervious areas. The Water Quality requirement is met for the Redevelopment. Water quality and TSS removal calculations are included in Appendices G and H. Manufacturer performance documentation for the Rain Guardian Turret and Jellyfish cartridge filtration unit is included in Appendix L. Standard 5 Higher Potential Pollutant Loads The proposed project use does not have anticipated Higher Potential Pollutant Loads(HPPL). No outdoor storage of hazardous materials,vehicle maintenance activities,or fueling operations are proposed within the project limits. The site is not anticipated to generate more than 1,000 vehicle trips per day, based upon the analysis provided in the Trip Generation Table below. Stormwater Report—LWM Administration Building—492 Sutton Street Page 10 Trip Generation Table ITE Land Use Variable Daily Rate* Raw Internal Pass-By Total Trip Category Daily Reductions Reductions Ends Trip Ends General 109 Flights 3.10 trips 338 - - 338 Aviation Airport per day per flight Aviation/Office 10 6.5 trips per 65 - - 65 Employees employee Fast Casual 21500 SF 225.9 trips 565 -141 (25% -187(44% 237 Restaurant per 1,000 sf internal) passerby) Tota l - - 968 -141 -187 640 *Values as provided in the ITE Trip Generation Manual,11 h Edition Standard 6 Critical Areas The project site is not located within Zone II or an Interim Wellhead Protection Area,and does not discharge to any Outstanding Resource Waters,Special Resource Waters,Shellfish Growing Areas, Bathing Beaches, or Cold- Water Fisheries as defined in the Massachusetts Stormwater Handbook. No Critical Area restrictions apply to this project. Standard 7 Redevelopment The proposed project constitutes Redevelopment as defined in the Massachusetts Stormwater Handbook,as it involves the disturbance and reconstruction of an existing, previously developed site that is substantially impervious.As a Redevelopment project,the applicable standard requires that the proposed stormwater management system result in an improvement in stormwater quality and quantity conditions over existing conditions to the maximum extent practicable, rather than full compliance with the new development standards. As documented throughout this report,the proposed system achieves the following improvements over existing conditions: • Peak discharge rates from the project site(net)are reduced for the 2-, 10-,and 25-year storm events. The peak discharge rate in the 2-and 100-year storm event at DP-1 is increased slightly,while the overall net total of all design points is reduced in the post-development condition. • Offsite runoff that currently flows unimpeded across the parking lot surface is intercepted by the stormwater basin,eliminating an existing sediment and pollutant loading pathway and mitigating peak flows. • Deep Sump Hooded Catch Basins are proposed to replace aged catch basin structures with no sumps or hoods. • A weighted average of approximately 87.9%TSS removal is achieved through the treatment train, compared to no treatment under existing conditions. • Groundwater recharge is provided to the maximum extent practicable through the vegetated detention areas and stormwater basin,compared to minimal to no recharge under existing conditions. Stormwater Report—LWM Administration Building—492 Sutton Street Page 11 • Low-impact design features, including the vegetated detention area and stormwater basin are incorporated into the site design. The proposed stormwater management system represents a substantial improvement in stormwater quality and quantity over existing conditions and constitutes compliance with Standard 7 for Redevelopment projects. Standard 8 Construction Period Pollution Prevention Erosion and sediment controls will be installed prior to land disturbance and maintained through permanent stabilization of all disturbed areas in accordance with the Massachusetts Erosion and Sediment Control Guidelines.The total land disturbance area of approximately 1.36 acres exceeds the one-acre threshold triggering the EPA NPDES General Permit for Discharge from Construction Activities;accordingly, a formal SWPPP is required and will be submitted prior to land disturbance. Standard 9 Long-Term Operation and Maintenance A Long-Term Operation and Maintenance Plan identifying BMP locations, required maintenance tasks, inspection schedules,and the responsible party for each BMP has been prepared and is included in Appendix I. Standard 10 Illicit Discharge The proposed project does not include any illicit discharges to the stormwater management system as defined in the Massachusetts Stormwater Handbook.An Illicit Discharge Compliance Statement is included in Appendix J. 4.2 Local Bylaw Compliance The following describes how the proposed project complies with the applicable design and performance criteria of the North Andover Stormwater Management and Erosion Control Regulations(Chapter 250), adopted June 21, 2022. §250-23A(1) Low-Impact Development Low-impact development measures have been incorporated into the project design to the maximum extent feasible given the site constraints documented in Section 1.1.The following LID features are proposed: • The vegetated detention areas within the primary parking lot island provides a low impact, permeable alternative to conventional islands,temporarily retaining stormwater and promoting treatment and nutrient uptake through the proposed plantings. Bioretention was analyzed for incorporation, but due to high groundwater was determined not to be feasible. • Rain Guardian inlet pretreatment units provide distributed,at-source pretreatment of parking lot runoff prior to discharge to the vegetated detention areas,consistent with LID principles of treating stormwater close to its source. The inlet units were selected for their ease of maintenance. • The stormwater basin intercepts offsite runoff before it contacts impervious surfaces,functioning as a naturalistic retention feature at the site perimeter. The basin is utilized for peak flow mitigation,as the majority of the development is within existing developed areas and retention is not feasible due to existing infrastructure and groundwater conditions. • All proposed catch basins are equipped with four-foot sumps and outlet hoods, providing pretreatment throughout the collection system. Conventional subsurface LID practices such as infiltration chambers, bioretention with engineered media,and permeable pavement are not feasible at this site due to the shallow ESHGW,the limited depth of the existing closed drainage infrastructure,and the absence of available land for additional surface BMPs within the developed Stormwater Report—LWM Administration Building—492 Sutton Street Page 12 project footprint. Additionally,the project area is situated at the low point of the airport's landside area, rendering piped to discharged retention systems impractical. §250-23A(3) Massachusetts Stormwater Standards Compliance with all applicable Massachusetts Stormwater Management Standards is documented in Section 5.1 of this report. §250-23B(1) Water Quality Performance Standards North Andover Chapter 250§250-23B(1) requires that new development standards(90%TSS removal/60%Total Phosphorus removal) apply to new development areas and redevelopment standards(80%TSS removal/50%TP removal)apply to redevelopment portions;or Retention of 1"times the total post-construction impervious on site. The project includes 7,360 sf of new development and 21,240 sf of redevelopment area,for a total post- construction impervious is 28,600sf. 1"over the total post-construction impervious is 2,384cf. Full retention of 2,384 cf of impervious runoff is not achievable on this site given the shallow ESHGW,the existing airport infrastructure,depth constraints of the existing closed drainage infrastructure,and the redevelopment character of the project.The project accordingly pursues compliance through the TSS and TP removal percentage path under§250-23B(1)(a),as well as retention where feasible in LID strategies to provide a combination which meets the intent of the performance standards. RETENTION VOLUME Retention Volume provided is as follows: .......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... BMP Contributing Impervious(sf) Retention Volume(cf) .......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... Vegetated Detention Areas 89970 211 cf .......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... Stormwater Basin 12506 2,835 cf .......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... Total 109476 3,047 cf ............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ Retention is met for 10,476 square feet of impervious—approximately 36%of the total post-construction impervious.The required retention volume for the 10,476 square feet is 873 cubic feet,and 3,047 cf is provided. TSS REMOVAL TSS Removals provided are as follows: Treatment Train 1: Rain Guardian Inlet to Vegetated Detention Area-01 to Jellyfish to DP-1 Total Impervious: 49621.00 1 (PR-1) Treatment Train 1 Removal Rate Removed Remaining Rain Guardian (Pre) 0% 0 1 VDA-01 80% 0.8 0.2 Jellyfish 84% 0.168 0.032 TSS Removed= 97% Stormwater Report—LWM Administration Building—492 Sutton Street Page 13 Treatment Train 2: Deep Sump Catch Basins to Jellyfish to DP-1 Total Impervious: 18,403.00 (PR-4.1,PR-4.2,PR-5.2,PR-2,P-6) Treatment Train 2 Removal Rate Removed Remaining Deep Sump CB 25% 0.25 0.75 Jellyfish 84% 0.63 0.12 TSS Removed= 88% Treatment Train 3: Rain Guardian Inlet to Vegetated Detention Area-02 to Existing Drainage System Total Impervious: 1 4,178.00 1 (PR-3.2) Treatment Train 3 Removal Rate Removed Remaining Rain Guardian(Pre) 0% 0 1 VDA-02 80% 0.8 0.2 TSS Removed= 80% Treatment Train 4:Overland Flow to Stormwater Basin Total Impervious: 1 19592.001 Adjacent developed areas Treatment Train 4 Removal Rate Removed Remaining Filter Strip(pre) 0% 0 1 Stormwater Basin 80% 0.8 0.2 TSS Removed= 80% Total Impervious Treated: =28,794 sf Average Weighted TSS Removal:87.9% The proposed treatment train achieves 87.9%average annual TSS removal from the combined square footage of new or redeveloped impervious area. The contributing impervious areas to the treatment systems exceeds the total post-construction impervious area. The required weighted average of 90%for new impervious(7,360sf)and 80%for Redevelopment(21,240sf)is 82.6%. The project's weighted average of 87.9%exceeds this calculated average. TOTAL PHOSPHORUS(TP) REMOVAL Total Phosphorus removal is provided through the stormwater infiltration BMP,vegetated detention areas,and cartridge filtration unit. The following is the estimated total phosphorus removals achieved through the project. Total Phosphorus Removals for each of the BMPs are estimated as follows: Stormwater Basin: 93%TP Reduction VDA-01: 93%TP Reduction VDA-02: 79%TP Reduction Filtration Unit: 70%TP Reduction Stormwater Report—LWM Administration Building—492 Sutton Street Page 14 Stormwater Basin Treatment Train Land Use Cover Type Area(sf) Area(ac) TP Load (lb/acre/yr)* Industrial Impervious 1592 0.04 1.78 Landscaped(HSG C) Pervious 21915 0.50 0.21 Forested(HSG C) Pervious 13226 0.30 0.12 SCM Load(P) 0.207 lb/year Cumulative P Load Reduction' 93% (Storage=>1"Runoff Depth) VDA-01 Treatment Train Land Use Cover Type Area(sf) Area(ac) TP Load (lb/acre/yr)* Industrial Impervious 4621 0.11 1.78 Landscaped(HSG C) Pervious 5359 0.12 0.21 SCM Load(P) 0.215 lb/year Cumulative P Load Reduction' 93% (Storage=>1"Runoff Depth) VDA-02 Treatment Train Land Use Cover Type Area(sf) Area(ac) TP Load (lb/acre/yr)* Industrial Impervious 4178 0.10 1.78 Landscaped(HSG C) Pervious 2259 0.05 0.21 SCM Load(P) 0.182 lb/year Cumulative P Load Reduction 79% (Storage=>5"Runoff Depth) Manufactured Filtration Unit Treatment Train Land Use Cover Type Area(sf) Area(ac) TP Load (lb/acre/yr)* Industrial Impervious 18403 0.42 1.78 Landscaped(HSG C) Pervious 2055 0.05 0.21 SCM Load(P) 0.762 lb/year Cumulative P Load Reduction 70% *Per Manufacturer Test Data *TP Loads from Table 3-1 of Attachment 3 to Appendix F of the MA MS4 General Permit. Load Reduction from Table 3-13 of Attachment 3 to Appendix F of the MA MS4 General Permit: Surface Infiltration(0.27 in/hr)BMP Performance Table for Storage equaling 1"Runoff Depth 2Load Reduction from Table 3-13 of Attachment 3 to Appendix F of the MA MS4 General Permit: Surface Infiltration(0.27 in/hr)BMP Performance Table for Storage equaling 5"Runoff Depth 3TP Load Reduction from Manufacturer's Test Data(See Appendix L) Stormwater Report-LWM Administration Building-492 Sutton Street Page 15 For the total of 28,794 square feet of impervious contributing to the BMPs,the project provides a weighted average of 76.3%Total phosphorus removal. Based on the existing developed conditions of a portion of the site, and site constraints as previously described,Total Phosphorus Removal for the most downgradient portions of the project are not achieved. However,the site balances the requirement by treating existing developed areas. §250-23D Critical Areas The project site is not located within Zone A or Zone B of the Lake Cochichewick watershed, the Watershed Protection District, or any other Critical Area as defined in Chapter 250 §250-23D. No enhanced Critical Area treatment requirements apply to this project. §250-23E(11), (18), (19) Hydrologic Methodology Hydrologic modeling was performed using HydroCAD applying NRCS TR-20 methodology, consistent with §250- 23E(11).Sheet flow lengths used in time of concentration calculations do not exceed 50 feet,consistent with§250- 23E(18). Rainfall depths were obtained from NOAA Atlas 14, Volume 10, Version 3 for the project location, consistent with§250-23E(19). §250-23E(20), (21) Soil Testing and Design Infiltration Rate Subsurface conditions at the proposed BMP locations were evaluated through borings, supplemented by from physical test pit investigations conducted by Hancock Associates (2023) at an immediately adjacent location (Homegrown Lacrosse project). The design infiltration rate of 0.27 inches per hour was derived from Rawls Rate table values. Boring logs are included in Appendix C. §250-23E(22), (25) Conveyance and Basin Sizing Stormwater conveyance pipes have been sized for the 25-year storm event. The stormwater basin has been sized with one foot of freeboard,consistent with§250-23E(25). §250 Article IX Long-Term Operation and Maintenance A Long-Term Operation and Maintenance Plan has been prepared and is included in Appendix I. Iin IIIIII IIIII The proposed stormwater management system achieves compliance through use of low-impact features, mitigation of offsite runoff flow,TSS removal and TP reduction through detention, infiltration,and manufactured filtration,and promotion of groundwater recharge to the maximum extent practical. The system has been designed within the significant physical constraints present at this site, including shallow seasonal high groundwater,significant previous development and infrastructure existing on site, limited depth of the existing closed drainage infrastructure,and the absence of available undeveloped land within the project footprint for conventional BMP siting. Post-development peak discharge rates and runoff volumes from the site are at or below pre-development rates for the 2-, 10-,and 25-year storm events. There are minimal increases in the 2-year and 100-year storm at DP-1, which are deminimis given the overall reduction and downstream shared discharge point of Design Points.The proposed treatment train achieves 87.9%average TSS Removal, meeting both the Massachusetts Stormwater Handbook Standard 4 requirement the North Andover Chapter 250 requirement. The proposed project constitutes Redevelopment under the Massachusetts Stormwater Handbook,and the stormwater management system represents a substantial and measurable improvement in stormwater quality and quantity over existing conditions. No adverse effects to adjacent properties,wetland resource areas,or the existing downstream drainage system are anticipated as a result of the proposed project. Stormwater Report—LWM Administration Building—492 Sutton Street Page 16 0000n Figure 1 -Site Location Map Stormwater Report—LWM Administration Building—492 Sutton Street Page 17 f ,�,I I �Vwl I`•8 ij u r' ' 9 �i Y yq° Pit{6 iIJ'i, n a,- i , LAWRENCE MUNICIPAL il�� it III IIIIIII�� 1/ I AIRPORT (LWM) } ADMINISTRATION BUILDING i I III PROJECT1 I LIMITS l rr II iIV I�I��i,Illuuw! �V 1 r "„ II r / J r / „, , e IIIIII°III ulllllllllllllllllll , t II r I� Illl r ! �I 11 f� �I r z r i r ry a i O r u I� 1 I�IIIIIIIIIIIIIIIII a I �+ s .V �u I , I��u I. r� R III) y II I I i y u�u "r 4 1 I u � / I., I r V / I V Il tlll u'Yly l� Y / � r I 'III IIIII RIIIIII��IIIIr �i F F F OSGOOD STREET ,rF VT I` NH 00 ��T� SI SITE LOCATION MAP �� ANDOVE'R LWM AIRPORT ADMIN BUILDING McCLURE TM CT 'R' 492 SUTTON STREET NORTH ANDOVER,MA NOTES SCALE DATE PROJECT NO. FIGURE N O. 1 1. Data Sources:Massachusetts Bureau of Geographic Information(MassGIS) 2 1:480 6/12/2026 2025000039-010 . Background:NearMap Imagery Figure 2-Resource Area Map Stormwater Report—LWM Administration Building—492 Sutton Street Page 18 ' �A a 5, `5 Aerial Irn,X'' t J 31 1 "2 0 Q3 Flood Zones(from Paper FIRMs,wher DEP Wetlands Detailed With Outlines NFHL Unavailable) 11 Banier BeactvSys;t riarrier Beach-Deep Marsh on ;,7, F_� [J Barner 8�eath�,'oastal Duriv nrje�a rickt,wduded or v Barn'er eea,cl,-i-Shrub,Swamp Areas of Critical Environmental Concern M_-, rjarrmr Seaci-i,,Afooided'F pimp'Coniferoius ACECs I:] &,,-jrner Beach-Wooded Swarrip Decidu;ous NHESP Estimated Habitats of Rare Boq Wildlife c-'1oasta1,,Pm,kk Efluff or's'ea cliff coastal f,�each t_I"Oun P, Zone Is coav�11 Cranboy'ry Bog Deep marsh, Public Water Supplies -'arner eeachr'oporl'Wo"iter S OpaliVvater 02 "'Apell 0 qu,0',itewmdr Intake kocky Intertidal Share ,I M 81r�e j S hl 7-0,�altbw march Meadow or Fen Zone Ils shrub sviamp Tid�'111 P"Nit, Wooded Swarfrip Coniferous NHESP Priority Habitats of Rare Species f,j"Nooded Gwamp C,10,ciduo,LAG 7�d S�oxamp Mb,ced Trees wooi& VT NH 00 4*1 RESOURCE AREA MAP NORTH ANDOVER LWM AIRPORT ADMIN BUILDING TM McCLURE CT R1 492 SUTTON STREET NORTH ANDOVER,MA NOTES SCALE DATE PROJECT NO. 1. Data Sources:Massachusetts Bureau of FIGURE NO. 2 Geographic Information(MassGIS) 2. Background:MassMapper Imagery NTS 6/12/2026 2025000039-010 Figure 3-USGSTopographic Map Stormwater Report—LWM Administration Building—492 Sutton Street Page 19 Irk 01 ,/, %„ I ii/ OF /; / f oil/mi/r�I r / �" � ' of 0(�V(�� N,1,111,111 lirrry .,,r.�arrr/c ,, it , r 0r �1 r , r r,J�riirar / �/ J' iiv�%ie,"rr / f �1A.0y,. roil, 0/0001, , r r 411jf��1i/��oi��r� l0 ➢Ill r�r0/100//o//f!l/��rrlr J1/roi//l r v,,,,,:,/jii/,r rrr�, / '" / UP" r9 irr�r/u ri%i/i�Gr of o/irrriaia/rim/i;oofr rrior rr '�i rr/ PROJECT LIMITS �� 1,,,,r� r fl % j a � VPAli IN Ir / r' �NW��Jtltrttd�l, H / fq% rr/oa/, /J ji: % % � �prlll%//GIlllll'Il1,J%f///%rl,N,1o1f(Jfll /f� %' ✓ 4,, hippo e /� r s ��%ice"/ /��j/r%, frr�� %11 % U�VY / OV�fN /r/ ///%%l ,r i r 41' riiior,/�0 x' / J r r s' i 01 9 r I. jlli/11f W ilwli, i i. ✓/„%"'/ r (011��i0/<O/////// �� f rSY « - miiir o l/rof f rra/II/////'i/ y 'llUrr �Y1 y/ r/ X %Io A lrl/r/r! �, ,ii �h/fJl...... ®' �'� 00''/0 r o �r o //`.. %1//iil1f1r1J/H,Illlh@UJI!/// ' '% r j/ l „ro mwww '>. H lJrll/%i9iagj0 fS r l ° 0% NHrrir 0lcJJi'///111i1%IWi/,Irllflllllrllrrrrir!!%lrf"''2" % � r i , ll 4 �' � � / , r N. Ir r i r. 'ri 'i lrr Y o,, 0/4 ® / %/ ®/ 011 l/ llll / ® /1 tl%�1YIIl/ �YY /r %///// , O� /r' rrr / ri, �� y101111t1/O%i////��ltllJ111f1J%//////%//G/G///%//rr/Ir/l/rii�0l�rllll�llr ��''l /1f(' ' D i /I 11 jll%/KlSyl! "Jiipi /// r l%% i j/i%l //rflfll/ 'f✓✓liyriir, It Allill �/�//%II I //�i/"a .,/�OfJ Of /' 0ylooG,i//oi �f l//G//1/%/%/Il//11" 6 r % f f%i%//%//l .. lull`i%/l/�////ri/%/%%//!%ra 11111,/io/� i 1F, oiiir' g� �r', VT ` NH 00 NORTH ti USGS TOPOGRAPHIC MAP ANDOVER LWM AIRPORT ADMIN BUILDING MCC L � � ETM CT Rl � � 492 BUTTON STREET NORTH ANDOVER,MA NOTES SCALE DATE PROJECT NO. FIGURE N O. 3 1. Data Sources:Massachusetts Bureau of Geographic Information(MassGIS) 2. Background:USGS Topographic 1:6000 6/12/2026 2025000039-010 Figure 4-FEMA Flood Insurance Rate Map Stormwater Report—LWM Administration Building—492 Sutton Street Page 20 National d Layer FIRMette FEMA Legend 7107'35"W 42043'5"N SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT Without Base Flood Elevation BFE \ \ \\ SPECIAL FLOOD With BFE or Depth Zone AE AO,AH,v,AR \\ \ \ HAZARD AREAS Regulatory Floodway \ o _ ll Q.�1�Annual Chance Flood Hazard Areas of 1%annual chance flood with average depth less than one foot or with drainage 1001 �- \\ areas of less than one square mile Zone X Future Conditions 1%Annual \�\\ v ;y Chance Flood Hazard ZoneX \\\\\\\\ \\ ww- \\\\\\\ Area withReduced Op IS due to \ \ OTHER AREAS OF _ Levee.See Notes. one \\\ \o\ Area with Flood Risk due to Levee FLOOD HAZARD No SCREEN Area o Flood Hazard X \ y y f Minimal l v��\ Effective LOM Rs \ OTHER AREAS Area of Undetermined Flood Hazard Zone \\ \\\\ \\\\ GENERAL -—-- Channel Culvert or Storm Sewer STRUCTURES i i Levee Dike or Floodwall n h Annual Chance 20.2 Cross Sections with 1°la Water Surface Elevation F\ N L \ \ _ \\; \ a- - - Coastal Transact \\ \\ s \\ _ �� ,\\ \\ \ •_ ,` �\\. �� Elevation Line F~., \\\ �,\ \\ Rase Flood Ele �B E) ti. > \ I I - IE. Limit of Stud Jurisdiction Boundary Coastal Transact Baseline �, \\ OTHER . \ Profile Baseline \ \ � FEATURES H dro ra hic Feature OF Digital Data Available N No Digital Data Available \\ MAP PANELS Unmapped The pin displayed on the map is an approximate \ \ \\\® oint selected by the user and does not represent \\ \ \\ \ \ \ \ \�� aauthon a iveproperty location. ion \\ \ \' rr This m complies with FEM standards for h u 3 s a co es t sta da ds o the use\ p p digital flood maps if it is not void as described below. The basemap shown complies with FEMA s basema AIIW curacy standards yyy y \y Ai v yyy ,y y The flood hazard information is derived directly from the AA \y yy �sy � A - authoritative NFHL web service provided y FEMA.This map y v s a ,fl � t was exported on C, ,2C2C at CSC PM and does not \. \\ \ \\ \ and \.�\ \ reflect changes or amendments subsequent to this date cha rl - 41-1 time a an effective information may n e or 00 �- � � �\ become superseded by new data over time. OR This map image is void if the one or more of the following map elements do not appear:basemap imagery,flood zone labels, legend scale bar,map creation date,community identifiers, FIRM panel number,and FIRM effective date.Map images for 11111111111117- Feet 1. 000 7106'58"W 42042'39"N unmapped and unmodernized areas cannot be used for 0 250 500 1,000 1,500 2,000 regulatory purposes. Basemap Imagery Source:USGS National Map 2023 Figure 5-Pre-Development Watershed Map Stormwater Report—LWM Administration Building—492 Sutton Street Page 21 m McCLU RE' M 225 Friend Street DP-1(EXISTING AIRFIELD CATCH BASIN) Suite 805 DP-2(OVERLAND FLOW) Boston,MA 02114 P 617-466-6765 ^^ Ankeny.lA I Carroll,IA _ � ��- -� \ Cedar Rapids,lA I Clive,lA WATERSHED MAP LEGEND: DP-2 Coralville,IA I Council Bluffs,lA Dodge, I Sioux Ciityy,lA Fort u Exn SUBCATCHMENT IDDP- Columh Ka y n,O \, North Kansas Cit MO Lenexa,a,KS Portsmouth, I Boston,MA DESIGN POINT NOTICE /I Exa.z I McClure Engineering Co.is not DP�r / I Ex-a.1 J respoaims damagesfoor llossesues, I ttt) ------- SUB-CATCHMENT DELINEATION / collective7,"Losses'welch arise / _� t^ �f I e t xisrwc I .- I� EXISTING CB rom fal ur o follow hese Plans, Tc TIME OF CONCENTRATION PATH _ 1 - nDMIUILDING Specifications,and theengineeringses BUILDING I EXISTING CB intent the conveyy,or for Losses 1 which arise from fallu a to obtain L 'ch ri e m r ' and/or follow the engineers'or % � surveyors'guidance with respect to inconsistgncesrambdggussisnor 1� Ex-7 i Ex-6 the conflicts Plans and tamed wiSpecificathins. f I EXISTING IST 2 EXISTING / CB1 EXISTING CB r / EXISTING - / � C63 / / _F rr , Ex, / . / j _ e 1 �� C 5 I EXISTING CB REVISIONS �L \\� `�,�✓ � _// �� L F - _ I"; REV 1 7/10/26 PEER REVIEW COMMENT s \ PROJECT INFO 2025000039-000 Ex-1a o61/2o26 1 \\\ _ N '- ENGINEER DRAWN BY CHECKED BY \ LL \ EX-2 a 1 I i 3 BLR LID BLR L0 0000 1 ` i -V o r � s 4 4 � U) G l T 1 U z �J l + Lua a_ w U)Bey '; =; z �T/ 2 ,- f �I =r Q p HOMEGROWNLLJ BUILDING M i -� LACROSSE � / S- \ —j z ' t - i a s p � W LLJ of z O w co U ul i LLJ z z {7 \ N _ I L O LLJ < i i v w - w W a P = 30 15 0 30 Q a N a1 �''�_ .. •� � �`= ,� -.�� - DRAWING NO. 3 DRN—EX Figure 6-Post-Development Watershed Map Stormwater Report—LWM Administration Building—492 Sutton Street Page 22 of=- DP-2(OFF-SITE M C C L U RR E TM OVERLAND FLOW) 225 Friend Street Suite 805 DP-1(EXISTING CB) Boston,MA 02114 P 617-466-6765 DP-2 _ EXISTING CB Anken IA Carroll,lA WATERSHED MAP LEGEND: — y. �` _ c• ,+ I Cedar Rapids,lA I Clive,lA COralville,IA I Council Bluffs,lA / __— • \ - Fort Dodge,IA I Sioux City,lA PR# SUBCATCHMENT ID ��-� — ;� f� `r � DP-1 ,� Columbia,MO I Macon,MO %N000l ,f+ -':;'; North Kansas City,MO tiA% Lenexa,KS oPn DESIGN POINT 1 — Portsmouth,NH I Boston,MA 1 AREA DRAIN PRy.1 J l - NOTICE:Co.is t G -—————- SUB CATCHMENT DELINEATION PROPOSED PRE I responls bleure Engineering orl able for any ssuues, 1 ADMINISTRATION I claims damages,or losses BUILDING PR (collectively,"Losses•'which arise 1- ) ——.——-— Tc-TIME OF CONCENTRATION PATH N I EXISTING CB from failure to follow these Plans, _— Pam. Specifications,and the engineering R-s.r yy Losses AREA DRAIN ` EXISTING CB which ersecfrom faior for obtain Px POND(OR OTHER STORAGE) ) , o ` CATCH l,. and/or follow the engineers'or CATCH BASIN _ PHs.z ..on ,., BASIN _ surveyors'guidance with respect to r �• +:.'.y r: .. * w M; t In •: �+ \\ — 1 I conflictsll codiSpecifications. ine amblgwith ned errors, uitiesnor ine _ an _ I �_ 'nc the Plans an o kI r CATCH BASIN _ I PR2 A .i WATER QUALITY r ( ° CATCH BASIN FILTRATION PR-6 \UNIT "- /' PRETREATMENT v I / INLET TT = R-1 I � I 1 EXISTING CB 7 .,' AREA \ VEGETATED I DRAIN — — DETENTION 7 P3 AREA 02 r / \ \ / (VDA-02) 7 it PRETREATMENT \ 7 \ 1 INLET AREA DRAIN I \ r�� 3 _ 4178sF I + EXISTING CB PAVED TO `►► REVISIONS 7 �� DA- �� 71111�11�� i i i1111�111 v oz VEGETATED i Y 4c I DETENTION ♦i _ I \ 1 36955E 1 1 (VDA 01) ,r PAVED TO VDA-01 �` f ) AREA A DRAIN REV.1-7/10/26-PEER REVIEW COMM ENTS PROJE INFO 35 SF I r —=__ 0oo 39- �"'-- ti ■� \ �, P VEMEN7 7 �_ 06/16/2026 M '1 STORMWATER �\ TO BASIN ENGINEER DRAWN BY CHECKED BY _ BASIN BLR LID PR 11 ✓i a E ��_ - �r (ELEV.156.5) 7 r \ 191 SF ROOF I ` - \ 7 926:SF ` 1.1 TO BAS INLO ec O�VDA-0141 I00 O - \ I i l W N 1,1995E GRAVEL TO BASIN O I� Q 167 SF BASIN TO BASIN -- r� S'� Z J -- L N z �\ HOMEGROWN O W M LACROSSE \ 1 BUILDING Q J Co o W W BUJ \ �; UmW � z Z C U 4t W<Z UJ a"IO T7 z� O W J Z s U) W a 30 15 0 30 0 W N 0 f- DRAWING NO. ,.. DRN—DV °° Iin IIIIII Appendix A-Site Plans (Separately Bound) Stormwater Report—LWM Administration Building—492 Sutton Street Page 23 Appendix B-NRCS Soil Survey Report Stormwater Report—LWM Administration Building—492 Sutton Street Page 24 Hydrologic Soil Group—Essex County, Massachusetts, Northern Part M 0 0 326200 326240 326280 326320 326360 326400 326440 420 42'56"N 420 42'56"N 0 (D f ON N 1p, CD ................ OF V," A, CY') M /010 �01 "vio A, CY) C\I ...........W, /d/ C) C) CO C14 CO CY) /'Or CO CY') CY) .................... (Y) 420 42'45"N 420 42'45"N 326200 326240 326280 326320 326360 326400 326440 3: 3: Map Scale:1:1,720 if printed on A portr-ait(S.5"x 11")sheet. 0 Meters N 0 25 50 100 150 0 50 100 200 VF et Map projection:Web Mercator Comer coordinates:WGS84 Edge tics:UTM Zone 19N WGS84 usDA Natural Resources Web Soil Survey 6/4/2026 Conservation Service National Cooperative Soil Survey Page 1 of 4 Hydrologic Soil Group—Essex County, Massachusetts, Northern Part MAP LEGEND MAP INFORMATION Area of Interest(AOI) C The soil surveys that comprise your AOI were mapped at .................................. Area of Interest(AOI) 1:15,800. El C/D Soils 13 D Warning:Soil Map may not be valid at this scale. Soil Rating Polygons A Not rated or not available Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil A/D Water Features line placement.The maps do not show the small areas of 0 B Streams and Canals contrasting soils that could have been shown at a more detailed scale. Transportation ® B/D Rails Please rely on the bar scale on each map sheet for map C Interstate Highways measurements. 0 C/D us Routes Source of Map: Natural Resources Conservation Service �� Web Soil Survey URL: 0 D Major Roads Coordinate System: Web Mercator(EPSG:3857) Not rated or not available Local Roads Maps from the Web Soil Survey are based on the Web Mercator Soil Rating Lines Background projection,which preserves direction and shape but distorts ` A Aerial Photography distance and area.A projection that preserves area,such as the Im Albers equal-area conic projection,should be used if more A/D accurate calculations of distance or area are required. B This product is generated from the USDA-NRCS certified data as B/D of the version date(s)listed below. C Soil Survey Area: Essex County, Massachusetts, Northern Part Survey Area Data: Version 21,Sep 5,2025 C/D Soil map units are labeled(as space allows)for map scales D 1:50,000 or larger. Not rated or not available Date(s)aerial images were photographed: Mar 1,2023—Sep 1, Soil Rating Points 2023 13 q The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background A/D compiled displayed on these maps.As a result,some minor B shifting of map unit boundaries may be evident. ® B/D usDA Natural Resources Web Soil Survey 6/4/2026 Conservation Service National Cooperative Soil Survey Page 2 of 4 Hydrologic Soil Group—Essex County, Massachusetts, Northern Part Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 305B Paxton fine sandy loam, C 0.6 9.0% 3 to 8 percent slopes 602 Urban land 6.2 91.0% Totals for Area of Interest 6.8 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential)when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential)when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition usDA Natural Resources Web Soil Survey 6/4/2026 Conservation Service National Cooperative Soil Survey Page 3 of 4 Appendix C-Subsurface Investigation Logs Stormwater Report—LWM Administration Building—492 Sutton Street Page 25 tm - ----- -R - a s CONOWE E-F B1 (R�nK � I/ LF o _ C 000,4el EXISTING ADMINISTRATION-154,13 TERMINAL BUILDING .9 R= .0 �) E GENERAL NOTES _ - 15 1 BASE PLAN DEVELOPED FROM A ELECTRONIC FILE PROVIDED COX AVIATION ON JANUARY 10,2025 ENTITLED"EXISTING g CONDITIONS",DEVELOPED BY:NITSCH ENGINEERING,DATED MAY 29,2020,UPDATED JANUARY 10,2025,ORGINIAL SCALE 1=20 DRAWING NO.EX-1,FILE:16037 TOP02-2025-0110.DWG _ - g - — 3 - = B-10 CCU 2.THE PROPOSED BUILDING FOOTPRINT WAS PROVIDED B®4:GW 409'bgs (OW) BY COX AVIATION ON JANUARY 8,2025 ENTITILED"PROJECT (Use Well) _ SKETCH",DEVELOPED BY STANTEC, Exist.Ground Elev.®155' B-2:GW a@ 35 bgs(We!!) DATED MAY 2020,ORIGINAL SCALE 1"=40',DRAWING NO.1 ESHGW®151.50 _2 Exist.Ground Elev.=155' - - - - FILE:BUILDING_FOOTPRINT_SLETCH.DWG ESHGW®151050 W) - - - - - - 3.GZA TEST BORINGS WERE LOCATED BASED ON TAPED MEASUREMENTS AND/OR LINE OF SIGHT FROM EXISTING SITE FEATURES.EXPLORATION LOCATIONS SHOULD BE co B-3 - CONSIDERED ACCURATE ONLY TO THE DEGREE IMPLIED 3 BY THE METHOD USED. B-10- - =� OW PROPOSED ADMINISTRATION LEGEND -1 7 TERMINAL BUILDING FOOTPRINT O� TEST BORINGS PERFORMED BY NEW ENGLAND BORING CONTRACTORS BETWEEEN MAY 12 AND MAY 15,2020. t B 1 OBSERVED AND LOGGED BY GZA PERSONNEL _ _ - ON DECEMEBER 17 AN 8 2 TEST BORINGS PERFORMED BY G&M SUBSURFACE t B5 � - - � - - D1 024.OBSERVED AND LOGGED 1 E T T T B-100 BY GZA PERSONNEL all I X X (OW) INDICATES INSTALLED WELL LOCATION r _ - LLI 8.1'b s a g 0 - Exist.Ground Elev.=157.1 7 b� ESHGW-149' EXISto Ground Elev.=15701 _ , 0 20' 40' 80' ESHGW-150.1` _ -100 B-10colax - - SCALE IN FEET UNLESS SPECIFICALLY STATED BY WRITTEN AGREEMENT THIS DRAWING IS THE SOLE PROPERTY OF GZA GEOENVIRONMENTAL INC.(GZA.THE INFORMATION SHOWN ON THE DRAWING IS SOLELY FOR USE BY GZA'S f CLIENT OR THE CLIENTS DESIGNATED REPRESENTATIVE FOR THE SPECIFIC PROJECT AND LOCATION IDENTIFIED LL- ON THE DRAWING.THE DRAWING SHALL NOT BE TRANSFERRED,REUSED,COPIED,OR ALTERED IN ANY MANNER FOR USE AT AN OTHER LOCATION OR FOR ANY OTHER PURPOSE WITHOUT THE PRIOR WRITTEN CONSENT OF GZA.ANY TRANSFER,REUSE,OR MODIFICATION TO THE DRAWING BY THE CLIENT OR OTHERS,WITHOUT THE PRIOR ASS! OO 33�� N WRITTEN EXPRESS CONSENT OF GZA,WILL BE AT THE USER'S SOLE RISK AND WITHOUT ANY RISK OR LIABILITY TO GZA. SHGW=153.9 NEW ADMINISTRATION BUILDING SU LAWRENCE MUNICIPAL AIRPORT B-101/101A B-103 � NORTH ANDOVER,MASSACHUSETTS ff o- CLF EXPLORATION LOCATION PLAN s PREPAR PR EPARED FOR. ED BY: GZAGeoEnvironmental,Inc. E TP-2 Y OTHERS) Engineers and Scientists COX AVIATION,LLC co - - TP-1(BY OTHERS) ) www.gza.com Exists ground=159.1 Exist,ground=158.7 � PROJ MGR: SD REVIEWED BY: BWF CHECKED BY: JDA �p Notes by McClure Engineering Company FIGURE RedOX=3(39' June 11 2026 DESIGNED BY: SD DRAWN BY: SD SCALE: AS SHOWN ^ R dOX=42" L d ESHGW__155.6 3� �� ESHGW=15503 DATE: PROJECT NO. REVISION NO. JANUARY 2024 01.0177837.00 0 TEST BORING LOG GZA Cox Aviation BORING NO.: B-100 " Lawrence Municipal Airport Admin Bldg SHEET: 1 of 1 Ge0Environmental�Inc. 492 Sutton St,North Andover,MA 01845 PROJECT NO: 01.0177837.00 Engineers and Scientists REVIEWED BY: SD Drilling Co.: G&M Subsurface Type of Rig: ATV Boring Location:See Plan H.Datum: NAD83 Foreman: Scott Canning Rig Model: GeoProbe 7822DT Ground Surface Elev.(ft.): 157.1 Final Boring Depth(ft.): 10 V.Datum:NAVD88 Logged By: Kyran Peters Drilling Method:HSA Date Start-Finish: 12/17/2024-12/17/2024 Au er/Casin Type: Groundwater Depth(ft. 9 9 yp HSA Sampler Type: Split Spoon I.D/O.D.(in): 3.25/6.625 I.D./O.D.(in.): 1-3/8"/2" Date Time Water Depth Casing Stab.Time Hammer Weight(lb.): 140 Sampler Hmr Wt(lb): 140 12/17/24 1343 8.1 8 10 min Hammer Fall(in.): 30 Sampler Hmr Fall(in): 30 Other: Autohammer Other: Casing Field Stratum Depth Blows/ Sample Sample Description and Identification o A.- a Depth Pen.Rec. Blows SPT E Test a)� Description (ft) Core No. (ft.) (in) (in) (per 6 in.) Value (Modified Burmister Procedure) � Data 0 w Rate S-1 0-2 24 16 6 $ S-1: Medium dense,brown,fine to coarse SAND and 1 0.5 TOPSOIL 156.6' 5 7 GRAVEL,some Silt,trace Roots, moist. 2 1 2 S-2 2-4 24 14 4 4 10 S-2: Medium dense,brown to tan,fine to coarse SAND, FILL 6 10 some Silt,little Gravel, moist. 3 4 4' 153.1' S-3 4-6 24 17 5 6 13 S-3: Medium dense,gray,fine to medium SAND and 7 12 SILT,trace Gravel, moist. 5 6 S-4 6-8 24 21 15 17 28 S-4: Medium dense,tan,fine to medium SAND and SILT, 11 11 little Gravel, moist. SAND 7 8 S-5 8-10 24 17 11 12 22 S-5: Medium dense,tan,fine to coarse SAND,little Silt, 10 22 little Gravel, moist. 9 10 3 10, 147.1' Bottom of boring at 10 feet. r 11 12 J 13 14 15 -' 1. Ground surface elevation provided by Cox Aviation from a plan entitled,"Existing Conditions Plan,"prepared by Nitsch Engineering,dated 12/3/2024. U) 2. BETA Group,Inc observed the boring and field screened the samples for VOCs. �e 3. Boring terminated at 10 feet below ground surface(bgs)after reaching target depth.Upon completion,the borehole was back-filled with soil cuttings to ground surface. OC a W ui oc CD co J See Log Key for explanation of sample description and identification procedures.Stratification lines represent approximate boundaries between soil and bedrock 00 types.Actual transitions may be gradual.Water level readings have been made at the times and under the conditions stated.Fluctuations of groundwater may Boring NO.: occur due to other factors than those present at the times the measurements were made. B-1 00 TEST BORING LOG GZA Cox Aviation BORING NO.: B-102 " Lawrence Municipal Airport Admin Bldg SHEET: 1 of 1 Ge0Environmental�Inc. 492 Sutton St,North Andover,MA 01845 PROJECT NO: 01.0177837.00 Engineers and Scientists REVIEWED BY: SD Drilling Co.: G&M Subsurface Type of Rig: ATV Boring Location:See Plan H.Datum: NAD83 Foreman: Scott Canning Rig Model: GeoProbe 7822DT Ground Surface Elev.(ft.): 157.1 Logged B Final Boring Depth ft): 10 V.Datum:NAVD88 gg y: Samantha Doyle Drilling Method:HSA Date Start-Finish: 12/17/2024-12/17/2024 Au er/Casin Type: Groundwater Depth(ft. 9 9 yp HSA Sampler Type: Split Spoon I.D/O.D.(in): 3.25/6.625 I.D./O.D.(in.): 1-3/8"/2" Date Time Water Depth Casing Stab.Time Hammer Weight(lb.): 140 Sampler Hmr Wt(lb): 140 12/18/24 0920 7 10 2 min Hammer Fall(in.): 30 Sampler Hmr Fall(in): 30 Other: Autohammer Other: Casing Field Stratum Depth Blows/ Sample Sample Description and Identification o A.- a Depth Pen.Rec. Blows SPT B Test a)� Description (ft) Core No. (ft.) (in) (in) (per 6 in.) Value (Modified Burmister Procedure) � Data 0 w Rate S-1 0-2 24 17 4 4 8 S-1: (Top 8"): Dark brown,fine to medium SAND,some 1 4 4 Silt,trace Roots,trace Gravel. 2 07 TOPSOIL 156.4' 1 (Bottom 9"):Brown,fine to coarse SAND,some Gravel, trace Silt. 3 2 S-2 2-4 24 14 5 3 10 S-2: Medium dense,brown,fine to coarse SAND,some 7 11 Gravel,little Silt, moist. 3 FI LL 4 S-3 4-6 24 8 5 6 18 S-3: Medium dense,brown,fine to coarse SAND,some 12 13 Silt,little Gravel, moist. 5 6 6' 151.1' S-4 6-8 24 15 17 14 28 S-4: Medium dense,tan to gray,fine to coarse SAND, 4 14 15 some Silt,little Gravel, moist. 7 $ SAND S-5 8-10 24 12 3 10 19 S-5: Medium dense,tan to gray,fine to medium SAND, 9 15 little Silt,wet. 9-- 10 5 10, 147.1' Bottom of boring at 10 feet. r 11 12 J 13 14 15 -' 1. Ground surface elevation provided by Cox Aviation from a plan entitled,"Existing Conditions Plan,"prepared by Nitsch Engineering,dated 12/3/2024. U) 2. BETA Group,Inc observed the boring and field screened the samples for VOCs. �e 3. Rock in split spoon from 10-12"below ground surface. pC 4. Auger chatter from 6-7 feet bgs. Q 5. Boring terminated at 10 feet below ground surface(bgs)after reaching target depth.Upon completion,the borehole was backfilled with soil cuttings to ground surface. W CD co See Log Key for explanation of sample description and identification procedures.Stratification lines represent approximate boundaries between soil and bedrock 00 types.Actual transitions may be gradual.Water level readings have been made at the times and under the conditions stated.Fluctuations of groundwater may Boring NO.: occur due to other factors than those present at the times the measurements were made. B-1 02 TEST BORING LOG GZA Fennick McCredie Architecture EXPLORATION NO.: B-2(OW) Proposed Airport Administration Building SHEET: 1 of 2 G eoE nvi ronmental, I nc. North Andover,Massachusetts PROJECT NO: 04.0191090.00 m Engineers and Scientists REVIEWED BY: MA Logged By: J.Szmyt Type of Rig:Truck Boring Location: See Plan H.Datum: NAD83 Drilling Co.: New England Boring Contractors Rig Model: CF-15 Ground Surface Elev.ft): 155.0 Foreman: K.Smith Drilling Method: Drive Final Boring Depth ft): 31 V.Datum: NAVD88 &Wash Date Start-Finish: 5/13/2020-5/13/2020 Hammer Type: Auto Hammer Sampler Type: SS Groundwater Depth(ft.) Hammer Weight(lb.): 140 Sampler O.D.(in.): 2.0 Date Time Water Depth Stab.Time Hammer Fall(in.): 30 Sampler Length(in.): 24 5/13/2020 08:53 a.m. 4.0 None Auger or Casing O.D./I.D Dia(in.): 4 Rock Core Size: None 5/14/2020 10:23 a.m. 3.5 24 hrs 5/15/2020 06:55 a.m. 3.5 4 hr Casing Stratum Depth Blows/ Sam le Sample Description a Field Q�Description>-_� Depth Pen.Rec. Blows SPT p p E Test (ft) Core No. (ft.) (in) (in) (per 6 in.) Value Modified Burmister a) Data o w" Rate Soil description from sidewall of s TOPSOIL 154. -Concrete ea hand excavated borehole:Top 1 \11 PVC pipe 1 � 4-inches: Dark brown,SILT andi. i\Bentonite fine SAND,trace roots.0.3 to FILL \2, 3.9 feet: Light brown to gray, 3.9 151.1 fine to medium SAND,little ——————— 5 Gravel,trace Silt,dry. (Above approx.3.9 feet) S-1 6-8 24 17 8 10 S-1: Medium dense,gray,fine 2 ND 11 19 21 to coarse SAND,some Silt,little -2"slotted PVC Gravel,wet. well pipe S-2 8-10 24 49 19 33 S-2: Very dense,gray,fine to ND 40 38 73 coarse SAND,some Silt,little SAND 10 Gravel,wet. 3 -12' 14 141.0 d S-3 14- 4 2 100/4 R S-3: Very dense,gray,fine to 4 1.4 15 14.3 M medium SAND,some Silt,little 00 Gravel,wet. N N . CD J 20 S-4 19-21 24 8 17 38 S-4: Very dense,gray,fine to ND 11 36 37 medium SAND,some Silt,little 74 . . • Gravel,wet. " GLACIAL TILL J d o fine dense,gray,Very:- S-5 24-26 24 19 24 45 S5 V d fi t ND N 25 . . . 59 74 >100 medium SAND,some Silt,trace W Gravel,wet. W 30 S-6 29-31 24 15 18 51 S-6: Very dense,gray,fine to ND W N1-The ground surface elevation at the this test boring location is based on interpolation of topographic contours shown on Figure 2-Exploration Location Plan.Elevations shown are in feet and refer to NAVD 1988 from the provided site plans. 2-Note that the boring location was re-excavated utilizing a VacMaster 4000 vac-truck to approximately 6 feet below existing round surface b s 9 p 9 pp Y 99 ( 9 )• W 3-Soil samples were screened for total volatile organic compounds(VOCs)using a PhoCheck Tiger organic vapor meter equipped with a photo-ionization gas detector. Total VOCs detected are reported in parts per millions(ppm)in the"Field Test Data"column."ND"indicates that VOCs were not detected above 1 ppm. d W 4-Piece of gravel observed at tip of sampling spoon at S-3 sample,therefore blow counts may not be representative. Q U_ See Log Key for explanation of sample description and identification procedures. Stratification lines represent Exploration No.: approximate boundaries between soil and bedrock types.Actual transitions may be gradual.Water level readings have B2 O been made at the times and under the conditions stated. Fluctuations of groundwater may occur due to other factors ( W) CD than those present at the times the measurements were made. TEST BORING LOG GZA Fennick McCredie Architecture EXPLORATION NO.: B-2(OW) Proposed Airport Administration Building SHEET: 2 of 2 G eoE nvi ronmental, I nc. North Andover,Massachusetts PROJECT NO: 04.0191090.00 m Engineers and Scientists REVIEWED BY: MA Logged By: J.Szmyt Type of Rig:Truck Boring Location: See Plan H.Datum: NAD83 Drilling Co.: New England Boring Contractors Rig Model: CF-15 Ground Surface Elev.ft): 155.0 Foreman: K.Smith Drilling Method: Drive Final Boring Depth ft): 31 V.Datum: NAVD88 &Wash Date Start-Finish: 5/13/2020-5/13/2020 Hammer Type: Auto Hammer Sampler Type: SS Groundwater Depth(ft.) Hammer Weight(lb.): 140 Sampler O.D.(in.): 2.0 Date Time Water Depth Stab.Time Hammer Fall(in.): 30 Sampler Length(in.): 24 5/13/2020 08:53 a.m. 4.0 None Auger or Casing O.D./I.D Dia(in.): 4 Rock Core Size: None 5/14/2020 10:23 a.m. 3.5 24 hrs 5/15/2020 06:55 a.m. 3.5 4 hr CasingStratum Depth Blows/ Sam le Sample Description is Field Q�Description>-_� Depth Pen.Rec. Blows SPT p p E Test (ft) Core No. (ft.) (in) (in) (per 6 in.) Value Modified Burmister a) Data c' w" Rate 55 52 >1 00 medium SAND,some Silt,trace Gravel,wet. 5 31 GLACIAL TI L624.o . End of exploration at 31 feet. 35 40 d 45 M 00 N N m J CD o U Q 50 Of m J a d N C) W J W d 55 W z 0 W W Q J W 60 N5-Borehole was backfilled with drill cuttings upon completion. CD U) C o a d W Q U- See Log Key for explanation of sample description and identification procedures. Stratification lines represent Exploration No.: approximate boundaries between soil and bedrock types.Actual transitions may be gradual.Water level readings have B2 O been made at the times and under the conditions stated. Fluctuations of groundwater may occur due to other factors ( W) CD than those present at the times the measurements were made. TEST BORING LOG w� GZA Fennick McCredie Architecture EXPLORATION NO.: B-3 ° Proposed Airport Administration Building SHEET: 1 of 1 G eoE nvi ronmental, Inc. North Andover,Massachusetts PROJECT NO: 04.0191090.00 ' Engineers and Scientists REVIEWED BY: MA Logged By: J.Szmyt Type of Rig:Truck Boring Location: See Plan H.Datum: NAD83 Drilling Co.: New England Boring Contractors Rig Model: CF-15 Ground Surface Elev.ft): 156.0 Foreman: K.Smith Drilling Method:Drive Final Boring Depth ft): 31 V.Datum: NAVD88 &Wash Date Start-Finish: 5/14/2020-5/14/2020 Hammer Type: Auto Hammer Sampler Type: SS Groundwater Depth(ft.) Hammer Weight(lb.): 140 Sampler O.D.(in.): 2.0 Date Time Water Depth Stab.Time Hammer Fall(in.): 30 Sampler Length(in.): 24 5/14/2020 11:21 a.m. 4.3 30 minutes Auger or Casing O.D./I.D Dia(in.): 4 Rock Core Size: None Casing Field Stratum Depth Blows/ Sam le Sample Description and Identification a Q a Depth Pen.Rec. Blows SPT E Test �,�Description — (ft) Core No. (ft.) (in) (in) (per 6 in.) Value (Modified Burmister Procedure) Data o w Rate Soil description from sidewall of hand excavated borehole: 0.3 ASPHALT 155.7 Light brown to gray,fine to medium SAND,little Gravel, 1 FILL trace Silt,dry.(Above approx. 3 feet) 3 153.0 5 S-1 6-8 24 14 12 12 S-1: Medium dense,gray,fine to medium SAND and 2 ND 11 18 23 SILT,trace Gravel,wet. S-2 8-10 24 22 31 57 S-2: Very dense,gray,fine to medium SAND,some Silt, ND 17 19 74 trace Gravel,wet. 10 3 SAND 14 142.0 15 S-3 14-16 24 13 33 18 S-3: Dense,gray,fine to medium SAND and SILT,little ND 17 18 35 Gravel,wet. Q LO co 20 S-4 19- 20 19 50 84 S-4: Very dense,gray,fine to medium SAND and SILT, ND m 20.7 75 100/2 >100 little Gravel,wet. IL O U Q GLACIAL TILL m J CD S-5 24-26 24 15 51 33 S-5: Very dense,gray,fine to medium SAND and SILT, ND 25 W 31 35 64 trace Gravel,wet. d J W N 0 z F_ 30 S-6 29-31 24 17 89 81 S-6: Very dense,gray,fine to medium SAND and SILT, ND W 37 72 >100 trace Gravel,wet. 31 125.0 End of exploration at 31 feet. 5 W 1 -The ground surface elevation at the this test boring location is based on interpolation of topographic contours shown on Figure 2- N CD u) Exploration Location Plan. Elevations shown are in feet and refer to NAVD 1988 from the provided site plans. C 2-Note that the boring location was pre-excavated utilizing a VacMaster 4000 vac-truck to approximately 6 feet below existing ground surface Q (bgs). 2 3-Soil samples were screened for total volatile organic compounds(VOCs)using a PhoCheck Tiger organic vapor meter equipped with a photo-ionization gas detector.Total VOCs detected are reported in parts per millions(ppm)in the"Field Test Data"column."ND"indicates that VOCs were not detected above 1 ppm. It 5-Borehole was backfilled with drill cuttings upon completion See Log Key for explanation of sample description and identification procedures. Stratification lines represent Exploration No.: approximate boundaries between soil and bedrock types.Actual transitions may be gradual.Water level readings have been made at the times and under the conditions stated. Fluctuations of groundwater may occur due to other factors B3 CD than those present at the times the measurements were made. TEST BORING LOG w� GZA Fennick McCredie Architecture EXPLORATION NO.: B-4 ° Proposed Airport Administration Building SHEET: 1 of 1 G eoE nvi ronmental, Inc. North Andover,Massachusetts PROJECT NO: 04.0191090.00 ' Engineers and Scientists REVIEWED BY: MA Logged By: J.Szmyt Type of Rig:Truck Boring Location: See Plan H.Datum: NAD83 Drilling Co.: New England Boring Contractors Rig Model: CF-15 Ground Surface Elev.ft): 155.2 Foreman: K.Smith Drilling Method:Drive Final Boring Depth ft): 29.6 V.Datum: NAVD88 &Wash Date Start-Finish: 5/15/2020-5/15/2020 Hammer Type: Auto Hammer Sampler Type: SS Groundwater Depth(ft.) Hammer Weight(lb.): 140 Sampler O.D.(in.): 2.0 Date Time Water Depth Stab.Time Hammer Fall(in.): 30 Sampler Length(in.): 24 5/15/2020 10:26 a.m. 4.9 15 minutes Auger or Casing O.D./I.D Dia(in.): 4 Rock Core Size: None Casing Field Stratum Depth Blows/ Sam le Sample Description and Identification a Q a Depth Pen.Rec. Blows SPT E Test �,�Description — (ft) Core No. (ft.) (in) (in) (per 6 in.) Value (Modified Burmister Procedure) Data o w Rate Soil description from sidewall of hand excavated borehole: 0.41 OPSOIL 154.8 Top 5-inches: Dark brown,SILT and fine SAND,trace 1 FILL roots.0.3 to 3 feet: Light brown,fine to medium SAND, trace Silt,trace Gravel,dry. (Above approx.3 feet) 3 ——————— 152_2 5 S-1 6-8 24 8 14 19 S-1: Dense, brown,fine to medium SAND,some Silt, 2 ND 27 43 46 trace Gravel,wet. S-2 8-10 24 11 22 19 S-2: Dense, brown,fine to medium SAND,little Silt,trace 1.8 18 25 37 Gravel,wet. 10 S-3 10-12 24 14 20 27 S-3: Very dense, brown,fine to medium SAND and SILT, 3 1.7 SAND 28 31 55 little Gravel,wet. S-4 12-14 24 19 30 33 S-4: Very dense, brown,fine to medium SAND and SILT, 1.4 32 41 65 little Gravel,wet. 15 S-5 14-16 24 16 27 33 S-5: Very dense, brown,fine to medium SAND, some Silt, ND 34 37 67 little Gravel,wet. S-6 16-18 24 19 30 27 S-6: Very dense, light brown,fine to medium SAND, ND 30 42 57 some Silt,little Gravel,wet. CD 18.2 137.0 00 0 20 S-7 19- 22 11 28 60 S-7: Very dense,gray,fine to medium SAND and SILT, ND m 20.8 81 100/4 >100 little Gravel,wet. IL O U Q m GLACIAL TILL CD 25 S-8 24- 16 11 46 72 97 S-8: Very dense,gray,fine to medium SAND and SILT, ND 25.3 100/4 little Gravel,wet. W d J W N z 30 S-9 29- 7 6 91 50/1 R S-9: Very dense,gray,fine to medium SAND and SILT, 4 ND 29.6 125.E W 29.6 trace Gravel,wet. Q End of exploration at 29.6 feet. J W N 1 -The ground surface elevation at the this test boring location is based on interpolation of topographic contours shown on Figure 2- CD u) Exploration Location Plan. Elevations shown are in feet and refer to NAVD 1988 from the provided site plans. C 2-Note that the boring location was pre-excavated utilizing a VacMaster 4000 vac-truck to approximately 6 feet below existing ground surface Q (bgs). 2 3-Soil samples were screened for total volatile organic compounds(VOCs)using a PhoCheck Tiger organic vapor meter equipped with a photo-ionization gas detector.Total VOCs detected are reported in parts per millions(ppm)in the"Field Test Data"column."ND"indicates that VOCs were not detected above 1 ppm. It 4-Piece of gravel observed at tip of sampling soon at S-9 sample,therefore blow counts may not be representative. See Log Key for explanation of sample description and identification procedures. Stratification lines represent Exploration No.: approximate boundaries between soil and bedrock types.Actual transitions may be gradual.Water level readings have been made at the times and under the conditions stated. Fluctuations of groundwater may occur due to other factors B4 CD than those present at the times the measurements were made. Appendix D-Pre-Development HydroCAD Report Stormwater Report—LWM Administration Building—492 Sutton Street Page 26 EX-1 EX-2 EX-5 EX-4.2 EX-3 EX- X-2 EX-4.1 EX- EX-4.2 EX-3 EX-4.1 EX- DP-2 DP-1 EX-6 DP-2(OFF-SITE AIRFIELD) D -1 - ) EX-7 EX-8 EX-9 EX-10 EX-7 EX-8 EX-9 EX-10 SubCat Reach Pond Link Routing Diagram for 24-1787EX00_SPR-Rev1 Prepared by McClure, Printed 7/10/2026 HydroCAD®10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 2 Area Listing (selected nodes) Area CN Description (acres) (subcatchment-numbers) 1.702 74 >75% Grass cover, Good HSG C (EX-1, EX-10, EX-2, EX-3, EX-5, EX-6, EX-7, EX-8, EX-9) 0.093 74 >75% Grass cover, Good, HSG C (EX-9) 0.004 98 Concrete Pads (EX-2) 0.051 89 Gravel roads HSG C (EX-1, EX-2) 0.002 98 Paved Walk (EX-2) 0.003 98 Paved bit conc access (EX-2) 1.399 98 Paved parking HSG C (EX-1, EX-10, EX-2, EX-3, EX-5, EX-6, EX-7, EX-8, EX-9) 0.139 98 Roofs HSG C (EX-10, EX-2, EX-4.1, EX-4.2, EX-9) 0.315 70 Woods, Good HSG C (EX-10, EX-2) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type/1/ 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 3 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentEX-1: EX-1 Runoff Area=22,841 sf 45.90% Impervious Runoff Depth=1.80" Tc=6.0 min CN=86 Runoff=1.11 cfs 0.079 of SubcatchmentEX-10: EX-10 Runoff Area=22,580 sf 38.72% Impervious Runoff Depth=1.58" Tc=6.0 min C N=83 Runoff=0.96 cfs 0.068 of SubcatchmentEX-2: EX-2 Runoff Area=47,039 sf 20.11% Impervious Runoff Depth=1.24" Flow Length=421' Tc=9.5 min CN=78 Runoff=1.36 cfs 0.112 of SubcatchmentEX-3: EX-3 Runoff Area=5,030 sf 68.67% Impervious Runoff Depth=2.13" Tc=6.0 min CN=90 Runoff=0.29 cfs 0.021 of SubcatchmentEX-4.1: EX-4.1 Runoff Area=1,952 sf 100.00% Impervious Runoff Depth=2.93" Tc=6.0 min CN=98 Runoff=0.14 cfs 0.011 of SubcatchmentEX-4.2: EX-4.2 Runoff Area=2,493 sf 100.00% Impervious Runoff Depth=2.93" Tc=6.0 min CN=98 Runoff=0.18 cfs 0.014 of SubcatchmentEX-5: EX-5 Runoff Area=11,911 sf 16.46% Impervious Runoff Depth=1.24" Tc=6.0 min CN=78 Runoff=0.39 cfs 0.028 of SubcatchmentEX-6: EX-6 Runoff Area=8,941 sf 45.02% Impervious Runoff Depth=1.72" Tc=6.0 min CN=85 Runoff=0.42 cfs 0.029 of SubcatchmentEX-7: EX-7 Runoff Area=1,060 sf 81.51% Impervious Runoff Depth=2.51" Tc=6.0 min CN=94 Runoff=0.07 cfs 0.005 of SubcatchmentEX-8: EX-8 Runoff Area=2,728 sf 80.72% Impervious Runoff Depth=2.41" Tc=6.0 min CN=93 Runoff=0.17 cfs 0.013 of SubcatchmentEX-9: EX-9 Runoff Area=34,925 sf 62.29% Impervious Runoff Depth=2.05" Tc=6.0 min CN=89 Runoff=1.91 cfs 0.137 of Link DP-1: DP-1 (EX-CB) Inflow=6.26 cfs 0.474 of Primary=6.26 cfs 0.474 of Link DP-2: DP-2(OFF-SITE AIRFIELD) Inflow=0.56 cfs 0.042 of Primary=0.56 cfs 0.042 of PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type/1/ 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 4 Summary for Subcatchment EX-1: EX-1 Runoff = 1.11 cfs @ 12.09 hrs, Volume= 0.079 af, Depth= 1.80" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 107483 98 Paved parking HSG C 1,110 89 Gravel roads HSG C 111248 74 >75% Grass cover, Good HSG C 227841 86 Weighted Average 12,358 54.10% Pervious Area 101483 45.90% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: EX-1 Hydrograph 1.11 cfs El Runoff ON Type III 24=hr 1 / 2=yr Rainfall=3.16" 'VE Runoff Area=22,841 sf Runoff Volume=0.079 of Runoff Depth=1.80 0 Tc=6.0 min CN=86 j i 0 ,%,.' r 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type/1/ 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment EX-1 0: EX-10 Runoff = 0.96 cfs @ 12.09 hrs, Volume= 0.068 af, Depth= 1.58" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 474 70 Woods, Good HSG C 87000 98 Paved parking HSG C 744 98 Roofs HSG C 137362 74 >75% Grass cover, Good HSG C 227580 83 Weighted Average 131836 61.28% Pervious Area 8,744 38.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-10: EX-10 Hydrograph 1 0.96 cfs I El Runoff / Type III 24=hr 2=yr Rainfall=3.16" Runoff Area=22,580 sf Runoff Volume=0.068of % Runoff Depth=1.58" ,0 Tc=6.0 min CN=83 0 "",,;,,/„/ o is%,/ %u-,,,/ ,a,/i U U U U U U U U U U U U U U U U U Y Y Y 1111'111'111'111'111 1111'111 U U U U U UU U U U U U U U` U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 5254 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 6 Summary for Subcatchment EX-2: EX-2 Runoff = 1.36 cfs @ 12.14 hrs, Volume= 0.112 af, Depth= 1.24" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 131226 70 Woods, Good HSG C 87871 98 Paved parking HSG C 132 98 Paved bit conc access 17104 89 Gravel roads HSG C 167 98 Concrete Pads 191 98 Roofs HSG C 100 98 Paved Walk 231248 74 >75% Grass cover, Good HSG C 477039 78 Weighted Average 377578 79.89% Pervious Area 9461 20.11% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.9 33 0.0730 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.74" 2.0 17 0.0250 0.14 Sheet Flow, Grass: Short n= 0.150 P2= 3.74" 2.0 275 0.0200 2.28 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.6 96 0.0200 2.87 Shallow Concentrated Flow, Paved Kv= 20.3 fps 9.5 421 Total PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 7 Subcatchment EX-2: EX-2 Hydrograph 1.36 cfS El Runoff Type III 24=hr 2=yr Rainfall=3.16" Runoff Area=47,039 sf Runoff Volume=0.112 of Runoff Depth=1.24" 0 Flow Length=421' Tc=9.5 min CN=78 i I'll //j / // % md, : 0 ,i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment EX-3: EX-3 Runoff = 0.29 cfs @ 12.09 hrs, Volume= 0.021 af, Depth= 2.13" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 37454 98 Paved parking HSG C 17576 74 >75% Grass cover, Good HSG C 57030 90 Weighted Average 17576 31.33% Pervious Area 3454 68.67% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-3: EX-3 Hydrograph 0.3 0.29 cfs El Runoff 0.28 Type III 24=hr 0.26 0.24 j 2=yr Rainfall=3.16" 0.22 Runoff Area 5,030 sf 0.2 % Runoff Volume=0.021 of 0.1s % _ 0.16 Runoff Depth=2.13" 3 0 Tc=6.0 min � 0.14 ,� 0.12, CN=90 0.1 !% 0.08 i 0.04 0.02 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type/1/ 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment EX-4.1: EX-4.1 Runoff = 0.14 cfs @ 12.08 hrs, Volume= 0.011 af, Depth= 2.93" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 17952 98 Roofs H S G C 17952 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-4.1: EX-4.1 Hydrograph 0.15 0.14 cfs El Runoff 0.14 Type III 24=hr 0.13 0.12 2=yr Rainfall=3.16" 0.11 Runoff Area=1,952 sf i 0.1 ' Runoff Volume=0.01 1 of 0.09 0.08 Runoff Depth=2.93" 0 0.07 ! Tc=6.0 min i CN=98 0.05 0.04 0.03 i' 0.02 % 0.01 0, U....U U UU U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type/1/ 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 10 Summary for Subcatchment EX-4.2: EX-4.2 Runoff = 0.18 cfs @ 12.08 hrs, Volume= 0.014 af, Depth= 2.93" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 27493 98 Roofs HSG C 27493 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-4.2: EX-4.2 Hydrograph 0.19 0.18 cfs El Runoff 0.18 0.17 / Type III 24=hr 0.16 2=yr Rainfall=3.16" 0.15 0.14 - / - - - Runoff Area=2 493 sf_ 0.13 0.1 Runoff JVolume=,0.0,14 of 2 0 0.11 / Runoff Depth=2.93" 0.1 '� c 0.09 % Tc=6.0 min 0.08 0.07 CN=98 0.06 0.05 0.04 0.03 0.02 � 0.01 011 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 11 Summary for Subcatchment EX-5: EX-5 Runoff = 0.39 cfs @ 12.09 hrs, Volume= 0.028 af, Depth= 1.24" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 17961 98 Paved parking HSG C 97950 74 >75% Grass cover, Good HSG C 117911 78 Weighted Average 91950 83.54% Pervious Area 1,961 16.46% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-5: EX-5 Hydrograph El Runoff 0.42 0.39 cfs 0.4 0.38Type% III 24=hr 0.36 � 0.34 2=yr Rainfall=3.16" 0.32 0.3 / Runoff Area=111,911 sf 0.28 _ % Runoff Volume=0.028 of 0.26 - - - - - - - 0.240.22 - - - Runoff Depth=1.24" 0 0.2UL - - - Tc=6.0 min 0.18 0.16 CN=78 0.14 % 0.12 i 0.1 0.06 - 0.04 0.02 10 0 , c ,/ c, i c/,/,; ,/,mail ,,,,,,,,,,� ,a ,�„ c- i uo/i o,,,i, c ,/ it i i,,,/c, w U U UU U U1 U U U U `` U U UU U U U UU U U U U U U U U U U U,U U U 1111 1111 1111 1111 1111 11111111 1111 U U` `` U U UU U U U U U U U U U UU U U U U U U U U mg'111 1111 1111 1111 1111 U UU U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 12 Summary for Subcatchment EX-6: EX-6 Runoff = 0.42 cfs @ 12.09 hrs, Volume= 0.029 af, Depth= 1.72" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 47025 98 Paved parking HSG C 47916 74 >75% Grass cover, Good HSG C 87941 85 Weighted Average 47916 54.98% Pervious Area 4,025 45.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-6: EX-6 Hydrograph 0.46 El Runoff 0.44 0.42 cfs 0.42 0.4 �� Type III 24=hr 0.38 0.36 2=yr Rainfall=3.16" 0.34 0.32 % Runoff Area=8,941 sf 0.3 - - - -0.28 - ;'% Runoff Volume=0.029 af- � 4 0.26 - - - - Runoff Depth=1,72" 0.24 C 022 ", Tc=6.0 m n � CN=85 0.16 0.14 0.12 0.1 ' 0.08 0.06 0.04 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 13 Summary for Subcatchment EX-7: EX-7 Runoff = 0.07 cfs @ 12.08 hrs, Volume= 0.005 af, Depth= 2.51" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 864 98 Paved parking HSG C 196 74 >75% Grass cover, Good HSG C 17060 94 Weighted Average 196 18.49% Pervious Area 864 81.51% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-7: EX-7 Hydrograph 0.075 El Runoff 0.07 cfs 0.07 �0.065 Type III 24-hr � 0.06 2=yr Rainfall=3.16' 0.05511111111 Runoff Area=1,060sf Runoff Volume=0.005 of 0.045 o 0.04 Runoff Depth=2.51 �� c 0.035 Tc=6,0 min 0.03 CN=94 0.025 !% 0.02 0.015 0.01 0.005 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 14 Summary for Subcatchment EX-8: EX-8 Runoff = 0.17 cfs @ 12.09 hrs, Volume= 0.013 af, Depth= 2.41" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 27202 98 Paved parking HSG C 526 74 >75% Grass cover, Good HSG C 27728 93 Weighted Average 526 19.28% Pervious Area 2,202 80.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-8: EX-8 Hydrograph 0.19 � � E Runoff 0.18 0.17 cfs 0.17 - - /, - - - - - - - - - - Type 0.16 III 24-hr- 0.15 2=yr RainfalI=3.16" � 0.14 Runoff Area=2 728 sf 0.13 0.12 Runoff Volume=0.013 of 0.11 0.1 Runoff Depth=2.41" 0 0.09 9: 0.08, Tc=6.0 min 0.07 CN=93 0.06 0.05 0.04 0.03 0.02 0.01 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type/1/ 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 15 Summary for Subcatchment EX-9: EX-9 Runoff = 1.91 cfs @ 12.09 hrs, Volume= 0.137 af, Depth= 2.05" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 695 98 Roofs HSG C 211059 98 Paved parking HSG C 97138 74 >75% Grass cover, Good HSG C 47033 74 >75% Grass cover, Good, HSG C 347925 89 Weighted Average 131171 37.71% Pervious Area 217754 62.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-9: EX-9 Hydrograph 2 1.91 cfs I El Runoff i Type III 24=hr j 2=yr Rainfall=3.16" Runoff Area=34,925 sf Runoff Volume=0.137 of Runoff Depth=2.05" 0 Tc=6.0 min CN=89 i U I Ui I my I 111�11rlirlirliq�111 I I I U U U U U U U U U U U U U U U U U U U U U U U U rrrvrTlir7lir7lir7ii7Flir7lipiI 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 16 Summary for Link DP-1: DP-1 (EX-CB) Inflow Area = 3.377 ac, 42.79% Impervious, Inflow Depth = 1.68" for 2-yr event Inflow = 6.26 cfs @ 12.10 hrs, Volume= 0.474 of Primary = 6.26 cfs @ 12.10 hrs, Volume= 0.474 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-1: DP-1 (EX-CB) Hydrograph 26 EMInflow 7 El Primary 6.26 cfs Inflow Area=3.377 ac 6 r 5 .. 4 3 / / o U: 3 ' 2 0 i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 17 Summary for Link DP-2: DP-2 (OFF-SITE AIRFIELD) Inflow Area = 0.331 ac, 30.92% Impervious, Inflow Depth = 1.54" for 2-yr event Inflow = 0.56 cfs @ 12.09 hrs, Volume= 0.042 of Primary = 0.56 cfs @ 12.09 hrs, Volume= 0.042 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-2: DP-2 (OFF-SITE AIRFIELD) Hydrograph Inflow Primary 0.6 0.56 cfs El Inflow Area=0.331 ac 0.55 0.5 0.45 0.4 3 0 0.3 LL 0.25 0.2 0.15 i 0.1 i 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 18 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentEX-1: EX-1 Runoff Area=22,841 sf 45.90% Impervious Runoff Depth=3.47" Tc=6.0 min CN=86 Runoff=2.10 cfs 0.151 of SubcatchmentEX-10: EX-10 Runoff Area=22,580 sf 38.72% Impervious Runoff Depth=3.17" Tc=6.0 min CN=83 Runoff=1.92 cfs 0.137 of SubcatchmentEX-2: EX-2 Runoff Area=47,039 sf 20.11% Impervious Runoff Depth=2.71" Flow Length=421' Tc=9.5 min CN=78 Runoff=3.05 cfs 0.244 of SubcatchmentEX-3: EX-3 Runoff Area=5,030 sf 68.67% Impervious Runoff Depth=3.88" Tc=6.0 min CN=90 Runoff=0.51 cfs 0.037 of SubcatchmentEX-4.1: EX-4.1 Runoff Area=1,952 sf 100.00% Impervious Runoff Depth=4.76" Tc=6.0 min CN=98 Runoff=0.22 cfs 0.018 of SubcatchmentEX-4.2: EX-4.2 Runoff Area=2,493 sf 100.00% Impervious Runoff Depth=4.76" Tc=6.0 min CN=98 Runoff=0.28 cfs 0.023 of SubcatchmentEX-5: EX-5 Runoff Area=11,911 sf 16.46% Impervious Runoff Depth=2.71" Tc=6.0 min CN=78 Runoff=0.87 cfs 0.062 of SubcatchmentEX-6: EX-6 Runoff Area=8,941 sf 45.02% Impervious Runoff Depth=3.37" Tc=6.0 min CN=85 Runoff=0.80 cfs 0.058 of SubcatchmentEX-7: EX-7 Runoff Area=1,060 sf 81.51% Impervious Runoff Depth=4.31" Tc=6.0 min CN=94 Runoff=0.11 cfs 0.009 of SubcatchmentEX-8: EX-8 Runoff Area=2,728 sf 80.72% Impervious Runoff Depth=4.20" Tc=6.0 min CN=93 Runoff=0.29 cfs 0.022 of SubcatchmentEX-9: EX-9 Runoff Area=34,925 sf 62.29% Impervious Runoff Depth=3.77" Tc=6.0 min CN=89 Runoff=3.44 cfs 0.252 of Link DP-1: DP-1 (EX-CB) Inflow=12.15 cfs 0.928 of Primary=12.15 cfs 0.928 of Link DP-2: DP-2(OFF-SITE AIRFIELD) Inflow=1.15 cfs 0.085 of Primary=1.15 cfs 0.085 of PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type 111 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 19 Summary for Subcatchment EX-1: EX-1 Runoff = 2.10 cfs @ 12.09 hrs, Volume= 0.151 af, Depth= 3.47" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 107483 98 Paved parking HSG C 1,110 89 Gravel roads HSG C 111248 74 >75% Grass cover, Good HSG C 227841 86 Weighted Average 12,358 54.10% Pervious Area 101483 45.90% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: EX-1 Hydrograph 2.10 cfs El Runoff 2 % Type III 24=hr // 10=yr Rainfall=5.00" Runoff Area=22,841 sf Runoff Volume=0.151 of Runoff Depth=3.47" 0 Tc=6,0 min CN=86 0 U U U 11 U U U U U U U U U U U7T"7""r7l i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 20 Summary for Subcatchment EX-1 0: EX-10 Runoff = 1.92 cfs @ 12.09 hrs, Volume= 0.137 af, Depth= 3.17" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 474 70 Woods, Good HSG C 87000 98 Paved parking HSG C 744 98 Roofs HSG C 137362 74 >75% Grass cover, Good HSG C 227580 83 Weighted Average 131836 61.28% Pervious Area 8,744 38.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-10: EX-10 Hydrograph 1.92 cfs El Runoff 2 Type III 24=hr j 10=yr Rainfall=5.00" Runoff Area=22,580 sf Runoff Volume=0.137 of Runoff Depth=3.17" 0 Tc=6.0 min j CN=83 0 UuUiummullj�iir7iir7iir7ii7ll�iiI 117117117111jjpripiii 0 2 4 6 8 10 12 14 16 1820 2224 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 21 Summary for Subcatchment EX-2: EX-2 Runoff = 3.05 cfs @ 12.13 hrs, Volume= 0.244 af, Depth= 2.71" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 131226 70 Woods, Good HSG C 87871 98 Paved parking HSG C 132 98 Paved bit conc access 17104 89 Gravel roads HSG C 167 98 Concrete Pads 191 98 Roofs HSG C 100 98 Paved Walk 231248 74 >75% Grass cover, Good HSG C 477039 78 Weighted Average 377578 79.89% Pervious Area 9461 20.11% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.9 33 0.0730 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.74" 2.0 17 0.0250 0.14 Sheet Flow, Grass: Short n= 0.150 P2= 3.74" 2.0 275 0.0200 2.28 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.6 96 0.0200 2.87 Shallow Concentrated Flow, Paved Kv= 20.3 fps 9.5 421 Total PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 22 Subcatchment EX-2: EX-2 Hydrograph 3.05 cfS El Runoff Type III 24=hr 10=yr Rainfall=5.00" Runoff Area=47,O39 sf Runoff Volume=0.244 of 2 ;! Runoff Depth=2.71.. 0 Flow Length=421' Tc=9.5 min 1 CN=78 0-FTTT'TTFn7Fp7FT I U I I I I U I I I I U I I III iiqll�IIF�IIPIIF�IIF]��IIF�IIF�IIF�IIF]��lI Tvrrpr-T TTFFFFTT171n17q71r-111 1111 1111,F;, c,-,,,,,,c,� „,,i ,,,,,„' ,/„,,,,,,,/,F;, 1111 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type 111 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 23 Summary for Subcatchment EX-3: EX-3 Runoff = 0.51 cfs @ 12.09 hrs, Volume= 0.037 af, Depth= 3.88" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 37454 98 Paved parking HSG C 17576 74 >75% Grass cover, Good HSG C 57030 90 Weighted Average 17576 31.33% Pervious Area 3454 68.67% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-3: EX-3 Hydrograph 0.55 0.51 cfs El Runoff 0.5 Type III 24=hr 0.45 10=yr Rainfall=5.00" 0.4 Runoff Area=5,030 sf ........ .... 0.35 Runoff Volume=0.037 of 0.3 % Runoff Depth=3.88" 0 0.25 Tc=6.0 min CN=90 0.15 0.1 0.05 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 24 Summary for Subcatchment EX-4.1: EX-4.1 Runoff = 0.22 cfs @ 12.08 hrs, Volume= 0.018 af, Depth= 4.76" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 17952 98 Roofs H S G C 17952 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-4.1: EX-4.1 Hydrograph 0.24 Runoff 0.23 0.22 cfs El 0.22 Type0.21 III 24=hr W 0.2 - - _ _0.1 - ,/ 10 r Rai nfal 1_5.00.; 9 y 0.18 Runoff Area=1,952f 0.17 s 0.16 Runoff Volume=0.018of 0 0.15 0.14 / 0.13 Runoff Depth=4,76" 3 0.12 ■ ,0 0.11 Tc=6.0 min 0.11, 0.09 CN=98 0.08 i . 6 0.05 0.04 0.03 ' 0.02 0.01 0, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 25 Summary for Subcatchment EX-4.2: EX-4.2 Runoff = 0.28 cfs @ 12.08 hrs, Volume= 0.023 af, Depth= 4.76" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 27493 98 Roofs HSG C 27493 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-4.2: EX-4.2 Hydrograph 0.3 0.28 cfs Runoff 0.28 Type III 24=hr 0.26 0.24 10=yr Rainfall=5.00" 0.22 Runoff Area=12,493f s 0.2 Runoff Volume=0.023 of 0.18 Runoff Depth=4,76" 0.16 C ; 0.14 Tc=6.0 min r 0.12 CN=98 0.1 r % j 0.06 0.040.02 0 r e,,, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 26 Summary for Subcatchment EX-5: EX-5 Runoff = 0.87 cfs @ 12.09 hrs, Volume= 0.062 af, Depth= 2.71" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 17961 98 Paved parking HSG C 97950 74 >75% Grass cover, Good HSG C 117911 78 Weighted Average 91950 83.54% Pervious Area 1,961 16.46% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-5: EX-5 Hydrograph 0.95 � Runoff 0.87 cfs 0.9 0.85 / Type III 24=hr 0.8 % 10=yr Rainfall=5.00,�0.75 7 Runoff Area=1 1 sf 0.65 Runoff Volume=0.062 of 0.550.5 Runoff Depth=2,71 o 0.45 Tc=6.0 min 0.35 CN=78 0.3 0.25 0.2 � 0.15 0.1 0.05 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 27 Summary for Subcatchment EX-6: EX-6 Runoff = 0.80 cfs @ 12.09 hrs, Volume= 0.058 af, Depth= 3.37" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 47025 98 Paved parking HSG C 47916 74 >75% Grass cover, Good HSG C 87941 85 Weighted Average 47916 54.98% Pervious Area 4,025 45.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-6: EX-6 Hydrograph 0.85 0.80 cfs 0 Runoff 0.8 Type III 24=hr 0.75 0.7 10=yr Rainfall=5.00" 0.65 Runoff Area=8,941 sf 0.6 0.55 / Runoff Vol u me-0.058 of ,4 0.5 0.45 - _ � ' Runoff Depth=3,37" 0 0.4 '�' Tc=6.0 min 0.35 � �� _ r - - - - - - - - - CN=85 0.3 0.25 0.2 0.15 0.1 i' 0.05 ' 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type 111 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 28 Summary for Subcatchment EX-7: EX-7 Runoff = 0.11 cfs @ 12.08 hrs, Volume= 0.009 af, Depth= 4.31" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 864 98 Paved parking HSG C 196 74 >75% Grass cover, Good HSG C 17060 94 Weighted Average 196 18.49% Pervious Area 864 81.51% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-7: EX-7 Hydrograph 0.125 Runoff 0.12 0.11 cfs El 11.0 0 % Type III 24=hr 11 , 0.105, / 0.1 / 1 0myr Rainfall=5.00" 0.095 0.09 Runoff Area=1,060 sf 0.085 0.08 Runoff Volume=0.009 of 0.075 0.07 - - Runoff Depth=4.31 0 0.06 �! Tc=6.0 min 9:0.055 0.05 CN=94 0.045 0.04 0.035 0.03 0.02 0.015 r� 0.01 0.005 %; 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 29 Summary for Subcatchment EX-8: EX-8 Runoff = 0.29 cfs @ 12.08 hrs, Volume= 0.022 af, Depth= 4.20" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 27202 98 Paved parking HSG C 526 74 >75% Grass cover, Good HSG C 27728 93 Weighted Average 526 19.28% Pervious Area 2,202 80.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-8: EX-8 Hydrograph 0.32 � Runoff 0.29 cfs 0.3 0.28, Type III 24=hr , 0.26 10=yr Rainfall=5.00" 0.24 0.22 Runoff Area=2,728 sf 0.2 Runoff Volume=0.022 of 4 0.18 Runoff-Depth=4.20�� 0.16 o 9: 0.14 min 0.12 CN=93 0.1 0.08 0.06 i 0.04 0.02 O „� ur%, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 30 Summary for Subcatchment EX-9: EX-9 Runoff = 3.44 cfs @ 12.09 hrs, Volume= 0.252 af, Depth= 3.77" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 695 98 Roofs HSG C 211059 98 Paved parking HSG C 97138 74 >75% Grass cover, Good HSG C 47033 74 >75% Grass cover, Good, HSG C 347925 89 Weighted Average 131171 37.71% Pervious Area 217754 62.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-9: EX-9 Hydrograph 3.44 cfs El Runoff Type III 24=hr 3 / 10=yr Rainfall=5.00" Runoff Area=34,925 sf Runoff Volume=0.252 of 2 / Runoff Depth=3.77" 0 Tc=6.0 min CN=89 1 � ,�� ''ri 0 �,",��„//�,,.„%�, �� 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 4850 5254 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 31 Summary for Link DP-1: DP-1 (EX-CB) Inflow Area = 3.377 ac, 42.79% Impervious, Inflow Depth = 3.30" for 10-yr event Inflow = 12.15 cfs @ 12.09 hrs, Volume= 0.928 of Primary = 12.15 cfs @ 12.09 hrs, Volume= 0.928 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-1: DP-1 (EX-CB) Hydrograph Inflow El Primary 13 2.15 cfs Inflow Area=3.377 ac 10 � 9 ,j n 8 3 � 6- 5- 4- 0- 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787 EX00_S P R-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 32 Summary for Link DP-2: DP-2 (OFF-SITE AIRFIELD) Inflow Area = 0.331 ac, 30.92% Impervious, Inflow Depth = 3.07" for 10-yr event Inflow = 1.15 cfs @ 12.09 hrs, Volume= 0.085 of Primary = 1.15 cfs @ 12.09 hrs, Volume= 0.085 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-2: DP-2 (OFF-SITE AIRFIELD) Hydrograph Inflow El ry 1.15 cfs Prima Inflow Area=0.331 ac O ' i 0 'IF711TI1711nllr7lllr"F"F"F"F-111�FIPFIF]�FIPII U U U U U U U U TVTnTTTFn"Tllr7lln"F'IT'IFlln"FllqllP i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 33 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentEX-1: EX-1 Runoff Area=22,841 sf 45.90% Impervious Runoff Depth=4.55" Tc=6.0 min CN=86 Runoff=2.73 cfs 0.199 of SubcatchmentEX-10: EX-10 Runoff Area=22,580 sf 38.72% Impervious Runoff Depth=4.23" Tc=6.0 min C N=83 Runoff=2.54 cfs 0.183 of SubcatchmentEX-2: EX-2 Runoff Area=47,039 sf 20.11% Impervious Runoff Depth=3.71" Flow Length=421' Tc=9.5 min CN=78 Runoff=4.17 cfs 0.334 of SubcatchmentEX-3: EX-3 Runoff Area=5,030 sf 68.67% Impervious Runoff Depth=4.99" Tc=6.0 min CN=90 Runoff=0.64 cfs 0.048 of SubcatchmentEX-4.1: EX-4.1 Runoff Area=1,952 sf 100.00% Impervious Runoff Depth=5.91" Tc=6.0 min CN=98 Runoff=0.27 cfs 0.022 of SubcatchmentEX-4.2: EX-4.2 Runoff Area=2,493 sf 100.00% Impervious Runoff Depth=5.91" Tc=6.0 min CN=98 Runoff=0.35 cfs 0.028 of SubcatchmentEX-5: EX-5 Runoff Area=11,911 sf 16.46% Impervious Runoff Depth=3.71" Tc=6.0 min CN=78 Runoff=1.19 cfs 0.085 of SubcatchmentEX-6: EX-6 Runoff Area=8,941 sf 45.02% Impervious Runoff Depth=4.44" Tc=6.0 min CN=85 Runoff=1.05 cfs 0.076 of SubcatchmentEX-7: EX-7 Runoff Area=1,060 sf 81.51% Impervious Runoff Depth=5.45" Tc=6.0 min CN=94 Runoff=0.14 cfs 0.011 of SubcatchmentEX-8: EX-8 Runoff Area=2,728 sf 80.72% Impervious Runoff Depth=5.33" Tc=6.0 min C N=93 Runoff=0.36 cfs 0.028 of SubcatchmentEX-9: EX-9 Runoff Area=34,925 sf 62.29% Impervious Runoff Depth=4.88" Tc=6.0 min C N=89 Runoff=4.40 cfs 0.326 of Link DP-1: DP-1 (EX-CB) Inflow=15.92 cfs 1.227 of Primary=15.92 cfs 1.227 of Link DP-2: DP-2(OFF-SITE AIRFIELD) Inflow=1.53 cfs 0.113 of Primary=1.53 cfs 0.113 of PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 34 Summary for Subcatchment EX-1: EX-1 Runoff = 2.73 cfs @ 12.09 hrs, Volume= 0.199 af, Depth= 4.55" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 107483 98 Paved parking HSG C 1,110 89 Gravel roads HSG C 111248 74 >75% Grass cover, Good HSG C 227841 86 Weighted Average 12,358 54.10% Pervious Area 101483 45.90% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: EX-1 Hydrograph 3 2.73 cfs El Runoff Type III 24=hr y 25= r Rainfall=6.15" � Runoff Area=22,841 sf Runoff Volume=0.199 of Runoff Depth=4.55" 0 Tc=6.0 min CN=86 0 %, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 35 Summary for Subcatchment EX-10: EX-10 Runoff = 2.54 cfs @ 12.09 hrs, Volume= 0.183 af, Depth= 4.23" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 474 70 Woods, Good HSG C 87000 98 Paved parking HSG C 744 98 Roofs HSG C 137362 74 >75% Grass cover, Good HSG C 227580 83 Weighted Average 131836 61.28% Pervious Area 8,744 38.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-10: EX-10 Hydrograph 2.54 cfs El Runoff Type III 24=hr j 25=yr Rainfall=6.15" 2 Runoff Area=22,580 sf Runoff Volume=0.183 of Runoff Depth=4.23" o Tc=6.0 min 1 CN=83 mil i O � '� //�l%„ ,1 c a a it 'u c r 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 36 Summary for Subcatchment EX-2: EX-2 Runoff = 4.17 cfs @ 12.13 hrs, Volume= 0.334 af, Depth= 3.71" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 131226 70 Woods, Good HSG C 87871 98 Paved parking HSG C 132 98 Paved bit conc access 17104 89 Gravel roads HSG C 167 98 Concrete Pads 191 98 Roofs HSG C 100 98 Paved Walk 231248 74 >75% Grass cover, Good HSG C 477039 78 Weighted Average 377578 79.89% Pervious Area 9461 20.11% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.9 33 0.0730 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.74" 2.0 17 0.0250 0.14 Sheet Flow, Grass: Short n= 0.150 P2= 3.74" 2.0 275 0.0200 2.28 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.6 96 0.0200 2.87 Shallow Concentrated Flow, Paved Kv= 20.3 fps 9.5 421 Total PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type 111 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 37 Subcatchment EX-2: EX-2 Hydrograph 4.17 cfS El Runoff 4 Type III 24=hr � 25=yr Rainfall=6.15" � Runoff Area=47,039 sf Runoff Volume=0.334 of Runoff Depth=3.71 0 Flow Length=421' r Tc=9.5 min CN=78 0 M/9 ',,,,� 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 38 Summary for Subcatchment EX-3: EX-3 Runoff = 0.64 cfs @ 12.08 hrs, Volume= 0.048 af, Depth= 4.99" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 37454 98 Paved parking HSG C 17576 74 >75% Grass cover, Good HSG C 57030 90 Weighted Average 17576 31.33% Pervious Area 3454 68.67% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-3: EX-3 Hydrograph El Runoff 0.7 0.64 cfs 0.65 T ype III 24=hr 0.6 0.55 25=yr Rainfall=6.15" 0.5 / Runoff Area=5,030 sf 0.45 Runoff Volume=0.048 of 0.4 a Runoff Depth=4.99" 3 0.35 j - Tc=6.0 min C 0.3, CN=90 i 0.15 0.1 0.05 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 39 Summary for Subcatchment EX-4.1: EX-4.1 Runoff = 0.27 cfs @ 12.08 hrs, Volume= 0.022 af, Depth= 5.91" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 17952 98 Roofs H S G C 17952 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-4.1: EX-4.1 Hydrograph 0.3 � � � Runoff 0.27 cfs � 0.28 0.26 Type III 24=hr �� - 0.24 25=yr Rainfall=6.15" 0.22 Runoff Area=1 952 sf Runoff Volume=0.022 of 0.18 0.16 Runoff Depth=5,91 o 0.14 Tc=6.0 min 0.12 0.1 CN=98 0.06 0.04 0.02 0 /sae U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 40 Summary for Subcatchment EX-4.2: EX-4.2 Runoff = 0.35 cfs @ 12.08 hrs, Volume= 0.028 af, Depth= 5.91" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 27493 98 Roofs HSG C 27493 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-4.2: EX-4.2 Hydrograph 0.38 Runoff 0.36 0.35 cfs El 0.34 Type III 24=hr- _ 0.32 0.3 25=yr Rainfall=6.15" - - - - Runoff Area-2,493 sf 0.24 Runoff Volume=0.028 of 0.22 - o 0.2 ! Runoff Depth=5,91 c 0.18 , 9: Tc=6.0 min 0.14 CN=98 0.12 - / 0.1 i 0.06 0.04 / 0.02 01 e,., ,,,,;, ,'Y„/%'a, U U U U UU U U Y Y Y Y U Y my Y U U U U Y U Ing 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 41 Summary for Subcatchment EX-5: EX-5 Runoff = 1.19 cfs @ 12.09 hrs, Volume= 0.085 af, Depth= 3.71" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 17961 98 Paved parking HSG C 97950 74 >75% Grass cover, Good HSG C 117911 78 Weighted Average 91950 83.54% Pervious Area 1,961 16.46% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-5: EX-5 Hydrograph 1.19 cfs El Runoff Type III 24=hr 25=yr Rainfall=6.15" Runoff Area=1 1 sf Runoff Volume=0.085 of Runoff Depth=3.71 0 Tc=6.0 min CN=78 0 U U U �111 U U UU U U U U U U U` U U U U U U U U U U U U U U Y U'III'III'III'III 'III'III'III U U U U U U U U U U U U uu 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 42 Summary for Subcatchment EX-6: EX-6 Runoff = 1.05 cfs @ 12.09 hrs, Volume= 0.076 af, Depth= 4.44" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 47025 98 Paved parking HSG C 47916 74 >75% Grass cover, Good HSG C 87941 85 Weighted Average 47916 54.98% Pervious Area 4,025 45.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-6: EX-6 Hydrograph 1.05 cfs El Runoff 1 % Type III 24=hr 25=yr Rainfall=6.15" j Runoff Area=8,941 sf Runoff Volume=0.076 of Runoff Depth=4.44" 3 ,0 Tc=6.0 min CN=85 0 J U U UU U U U U U U U U-F-F-FTTTF-F]II�IIFIIFIIFiiFillliiiI TTTTFn7rp7rwTT I I I I U I I I uTTTTTTrnriTiir7ii7iir7ii7Fii7iiiI 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 43 Summary for Subcatchment EX-7: EX-7 Runoff = 0.14 cfs @ 12.08 hrs, Volume= 0.011 af, Depth= 5.45" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 864 98 Paved parking HSG C 196 74 >75% Grass cover, Good HSG C 17060 94 Weighted Average 196 18.49% Pervious Area 864 81.51% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-7: EX-7 Hydrograph 0.15 0.14 cfs El Runoff 0.14 Type III 24=hr 0.13 25=yr Rainfall=6.15" 0.12 0.11 Runoff Area=1,060 sf 0.1 Runoff Volume=0.01 1 of 0.09 0.08 Runoff Depth=5,45" 3 — 0.07 0 Tc=6.0 min 0.06 ' CN=94 � r 0.05 ' 0.04 0.02 0.01ImxAn' 0 „ 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 44 Summary for Subcatchment EX-8: EX-8 Runoff = 0.36 cfs @ 12.08 hrs, Volume= 0.028 af, Depth= 5.33" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 27202 98 Paved parking HSG C 526 74 >75% Grass cover, Good HSG C 27728 93 Weighted Average 526 19.28% Pervious Area 2,202 80.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-8: EX-8 Hydrograph 0.4 Runoff o.3s 0.36 cfs El 0.36 % Type III 24=hr 03. 4 0.32 25=yr Rainfall=6.15" 0.3 Runoff Area-2 728 sf 0.2s - 0.26 % .-. 0.24 Runoff Volume=0.028 of 0.22 % Runoff Depth=5,33" 3 0.2 ' ° 0.18 Tc=6.0 min 0.16,111, - - - - - - - CN=93 0.14 0.12 i 0.1 0.08 0.06 - - 0.04 0.02 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 45 Summary for Subcatchment EX-9: EX-9 Runoff = 4.40 cfs @ 12.08 hrs, Volume= 0.326 af, Depth= 4.88" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 695 98 Roofs HSG C 211059 98 Paved parking HSG C 97138 74 >75% Grass cover, Good HSG C 47033 74 >75% Grass cover, Good, HSG C 347925 89 Weighted Average 131171 37.71% Pervious Area 217754 62.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-9: EX-9 Hydrograph 4.40 cfs El Runoff Type III 24=hr NO 4 � 25-yr Rainfall=6.15" Runoff Area=34,925 sf 3 Runoff Volume=0.326 of Runoff Depth=4.88" 0 Tc-=6.0 min 2, CN=89 j, i i � /0 Ur i i M9 , UU U U U U U U U UU U U U U U U U U U 0 2 4 6 8 10 12 14 16 1820 2224 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 46 Summary for Link DP-1: DP-1 (EX-CB) Inflow Area = 3.377 ac, 42.79% Impervious, Inflow Depth = 4.36" for 25-yr event Inflow = 15.92 cfs @ 12.09 hrs, Volume= 1.227 of Primary = 15.92 cfs @ 12.09 hrs, Volume= 1.227 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-1: DP-1 (EX-CB) Hydrograph Inflow 17 5.92 cfs El Primary 16 ' Inflow Area=3.377 ac 14 13 12 402 10 3 o � ,r 7 6 5 3° / i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 47 Summary for Link DP-2: DP-2 (OFF-SITE AIRFIELD) Inflow Area = 0.331 ac, 30.92% Impervious, Inflow Depth = 4.09" for 25-yr event Inflow = 1.53 cfs @ 12.09 hrs, Volume= 0.113 of Primary = 1.53 cfs @ 12.09 hrs, Volume= 0.113 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-2: DP-2 (OFF-SITE AIRFIELD) Hydrograph 1-1_53Inflow El ry 1.53 cfs Prima Inflow Area=0.331 ac j oWOW// i i /r/ /,i'i' 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 48 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentEX-1: EX-1 Runoff Area=22,841 sf 45.90% Impervious Runoff Depth=6.26" Tc=6.0 min CN=86 Runoff=3.70 cfs 0.274 of SubcatchmentEX-10: EX-10 Runoff Area=22,580 sf 38.72% Impervious Runoff Depth=5.91" Tc=6.0 min CN=83 Runoff=3.50 cfs 0.255 of SubcatchmentEX-2: EX-2 Runoff Area=47,039 sf 20.11% Impervious Runoff Depth=5.33" Flow Length=421' Tc=9.5 min CN=78 Runoff=5.94 cfs 0.479 of SubcatchmentEX-3: EX-3 Runoff Area=5,030 sf 68.67% Impervious Runoff Depth=6.74" Tc=6.0 min CN=90 Runoff=0.85 cfs 0.065 of SubcatchmentEX-4.1: EX-4.1 Runoff Area=1,952 sf 100.00% Impervious Runoff Depth=7.69" Tc=6.0 min CN=98 Runoff=0.35 cfs 0.029 of SubcatchmentEX-4.2: EX-4.2 Runoff Area=2,493 sf 100.00% Impervious Runoff Depth=7.69" Tc=6.0 min CN=98 Runoff=0.45 cfs 0.037 of SubcatchmentEX-5: EX-5 Runoff Area=11,911 sf 16.46% Impervious Runoff Depth=5.33" Tc=6.0 min CN=78 Runoff=1.69 cfs 0.121 of SubcatchmentEX-6: EX-6 Runoff Area=8,941 sf 45.02% Impervious Runoff Depth=6.15" Tc=6.0 min CN=85 Runoff=1.43 cfs 0.105 of SubcatchmentEX-7: EX-7 Runoff Area=1,060 sf 81.51% Impervious Runoff Depth=7.21" Tc=6.0 min CN=94 Runoff=0.19 cfs 0.015 of SubcatchmentEX-8: EX-8 Runoff Area=2,728 sf 80.72% Impervious Runoff Depth=7.09" Tc=6.0 min CN=93 Runoff=0.48 cfs 0.037 of SubcatchmentEX-9: EX-9 Runoff Area=34,925 sf 62.29% Impervious Runoff Depth=6.62" Tc=6.0 min CN=89 Runoff=5.86 cfs 0.442 of Link DP-1: DP-1 (EX-CB) Inflow=21.76 cfs 1.701 of Primary=21.76 cfs 1.701 of Link DP-2: DP-2(OFF-SITE AIRFIELD) Inflow=2.14 cfs 0.158 of Primary=2.14 cfs 0.158 of PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 49 Summary for Subcatchment EX-1: EX-1 Runoff = 3.70 cfs @ 12.08 hrs, Volume= 0.274 af, Depth= 6.26" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 107483 98 Paved parking HSG C 1,110 89 Gravel roads HSG C 111248 74 >75% Grass cover, Good HSG C 227841 86 Weighted Average 12,358 54.10% Pervious Area 101483 45.90% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: EX-1 Hydrograph 4 3.70 cfs El Runoff Type III 24=hr 100=yr Rainfall=7.93" Runoff Area=22,841 sf Runoff Volume=0.274 of Runoff Depth=6.26" 3 2 Tc=6.0 min CN=86 0 1 U U U UU U U U_V11 P U UU U U U U U j U U U-FTV-FF-FTIIF�IIF�IIF�IITIIFTIFF U U UU U U U U U U U U U U U U U U U U U U U U U U U U 1111 1111 1111 1111 U 1111 11111111 U U U U U u U U U U U U U U U U U U U U U U U U U U U U U U U 1111 1111 1111 U 1111 11111111 1111 U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U 1111 U 1111 11111111 1111 U 1111 U j /'- 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 50 Summary for Subcatchment EX-10: EX-10 Runoff = 3.50 cfs @ 12.09 hrs, Volume= 0.255 af, Depth= 5.91" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 474 70 Woods, Good HSG C 87000 98 Paved parking HSG C 744 98 Roofs HSG C 137362 74 >75% Grass cover, Good HSG C 227580 83 Weighted Average 131836 61.28% Pervious Area 8,744 38.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-10: EX-10 Hydrograph 3.50 cfs El Runoff % Type III 24=hr 3 j 100=yr Rainfall-7.93" Runoff Area=22,580 sf Runoff Volume=0.255 of Runoff Depth=5,91 Tc=6.0 min CN=83 0 i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 51 Summary for Subcatchment EX-2: EX-2 Runoff = 5.94 cfs @ 12.13 hrs, Volume= 0.479 af, Depth= 5.33" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 131226 70 Woods, Good HSG C 87871 98 Paved parking HSG C 132 98 Paved bit conc access 17104 89 Gravel roads HSG C 167 98 Concrete Pads 191 98 Roofs HSG C 100 98 Paved Walk 231248 74 >75% Grass cover, Good HSG C 477039 78 Weighted Average 377578 79.89% Pervious Area 9461 20.11% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.9 33 0.0730 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.74" 2.0 17 0.0250 0.14 Sheet Flow, Grass: Short n= 0.150 P2= 3.74" 2.0 275 0.0200 2.28 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.6 96 0.0200 2.87 Shallow Concentrated Flow, Paved Kv= 20.3 fps 9.5 421 Total PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 52 Subcatchment EX-2: EX-2 Hydrograph 5.94 cfS El Runoff 6 j Type III 24=hr 100myr Rainfall=7.93" Runoff Area=47,039 sf i Runoff Volume=0.479 of Runoff Depth=5.33" 0 3 Flow Length=421' Tc=9.5 min 2 CN=78 0 lqllpllF�IIPIIF�IIF]��IIF�IIF�IIF�IIF]��IlI U U U U U UU U U U U U U U U UU U U U U U U U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 53 Summary for Subcatchment EX-3: EX-3 Runoff = 0.85 cfs @ 12.08 hrs, Volume= 0.065 af, Depth= 6.74" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 37454 98 Paved parking HSG C 17576 74 >75% Grass cover, Good HSG C 57030 90 Weighted Average 17576 31.33% Pervious Area 3454 68.67% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-3: EX-3 Hydrograph 0.95 E Runoff - 0.9 0.85 cfs 0.85 % Type III 24=hr 0.8 0.75 1 00-y r Rainfall=7.93" 0.7 0.65 Runoff Area=5 030 sf VIA 0.6 Runoff Volume=0.065 of 0.55 0.5 Runoff Depth=6.74" 3 % 0 0.45 Tc=6.00.4 min �, 0.35 CN=90 0.3 ° 0.25 0.15 ' / 0.1 0.05 ' 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 54 Summary for Subcatchment EX-4.1: EX-4.1 Runoff = 0.35 cfs @ 12.08 hrs, Volume= 0.029 af, Depth= 7.69" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 17952 98 Roofs H S G C 17952 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-4.1: EX-4.1 Hydrograph 0.38 0.35 cfs El Runoff 0.36 0.34 / Type III 24=hr 0.32 � � 100yr Rainfall=7.93" 0.28 Runoff Area=1,952 sf 0.26 ;! 0.24 Runoff Volume=0.029 of ,4 0.22 0.2 ! Runoff Depth=7,69" 0 0.18Tc=6.0 min 0.16 CN=980.14 _ 0.12 0.1 0.08 i� 0.06 / 0.04 0.02 01 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 55 Summary for Subcatchment EX-4.2: EX-4.2 Runoff = 0.45 cfs @ 12.08 hrs, Volume= 0.037 af, Depth= 7.69" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 27493 98 Roofs HSG C 27493 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-4.2: EX-4.2 Hydrograph 0.48 0.45 cfs E Runoff 0.46 0.44 Type III 24=hr _ 100=yr Rainfall=7.93" 0.36 0.34 Runoff Area-2 493 sf 0.32 Runoff Volume=,0.037 of 0.28 0.26 Runoff Depth=7.69" 3 0.24 0.22 Tc=6.0 min 0.2 0.18 CN=98 0.16 0.14 , 0.12 0.1 0.08 i 0.06 0.04 0.02 011 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 56 Summary for Subcatchment EX-5: EX-5 Runoff = 1.69 cfs @ 12.09 hrs, Volume= 0.121 af, Depth= 5.33" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 17961 98 Paved parking HSG C 97950 74 >75% Grass cover, Good HSG C 117911 78 Weighted Average 91950 83.54% Pervious Area 1,961 16.46% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-5: EX-5 Hydrograph 1.69 cfs El Runoff Type III 24=hr j 100=yr Rainfall=7.93" j Runoff Area=11,911 sf Runoff Volume=0.121 of 1 % Runoff Depth=5.33" 0 Tc=6.0 min CN=78 0 %,0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 u- 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 57 Summary for Subcatchment EX-6: EX-6 Runoff = 1.43 cfs @ 12.09 hrs, Volume= 0.105 af, Depth= 6.15" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 47025 98 Paved parking HSG C 47916 74 >75% Grass cover, Good HSG C 87941 85 Weighted Average 47916 54.98% Pervious Area 4,025 45.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-6: EX-6 Hydrograph 1.43 cfs El Runoff Type III 24=hr ON 100=yr Rainfall=7.93" Runoff Area=8,941 sf 1 � — Runoff Volume=0.105 of Runoff Depth=6.15" 0 Tc=6.0 min CN=85 „ 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 5254 56 5860 62 6466 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 58 Summary for Subcatchment EX-7: EX-7 Runoff = 0.19 cfs @ 12.08 hrs, Volume= 0.015 af, Depth= 7.21" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 864 98 Paved parking HSG C 196 74 >75% Grass cover, Good HSG C 17060 94 Weighted Average 196 18.49% Pervious Area 864 81.51% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-7: EX-7 Hydrograph El Runoff 0.2 0.19 cfs 0.19 0.18Type III 24=hr 0.17 0.16 / 100=yr Rainfall�7.93" 0.15 Runoff Area=1,060 sf 0.14 0.13 n f Volume=0.015 Ru offa 0.12 Runoff Depth=7,21 0.1 0 - 0.09 Tc=6.0 min / 0.08 CN=94 0.07 0.06 0.05 - - - - - - - 0.04 0.03 0.02 / 0.01 / U U UU U U U UU U U U U U U U U UU U U U U U U U U UU U U U 1111 1111 1111 11111111 11111111 1111 U U U U U U U UU U U U UU U U U U U U U U UU U U U U U U U U mg 1111 1111 1111 1111 1111 U UU U U U U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 59 Summary for Subcatchment EX-8: EX-8 Runoff = 0.48 cfs @ 12.08 hrs, Volume= 0.037 af, Depth= 7.09" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 27202 98 Paved parking HSG C 526 74 >75% Grass cover, Good HSG C 27728 93 Weighted Average 526 19.28% Pervious Area 2,202 80.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-8: EX-8 Hydrograph 0.5 0.48 cfs 0 Runoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . �� % - - - _ _ �� - �� Type0.45 III 24=h 100myr Rainfall=7.93" Runoff Area=2,728 sf Runoff Volume=0.037 of 0.3 Runoff Depth=7,09" 0 0.25 Tc=6.0 min 0.2 CN=93 0.15 // 0.1 0.05 i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 60 Summary for Subcatchment EX-9: EX-9 Runoff = 5.86 cfs @ 12.08 hrs, Volume= 0.442 af, Depth= 6.62" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 695 98 Roofs HSG C 211059 98 Paved parking HSG C 97138 74 >75% Grass cover, Good HSG C 47033 74 >75% Grass cover, Good, HSG C 347925 89 Weighted Average 131171 37.71% Pervious Area 217754 62.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-9: EX-9 Hydrograph I El Runoff 5.86 cfs 6, Type III 24=hr 100=yr Rainfall=7.93" j Runoff Area=34,925 sf 4 Runoff Volume=0.442 of Runoff Depth=6.62" UL Tc=6.0 min CN=89 %j 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 61 Summary for Link DP-1: DP-1 (EX-CB) Inflow Area = 3.377 ac, 42.79% Impervious, Inflow Depth = 6.04" for 100-yr event Inflow = 21.76 cfs @ 12.09 hrs, Volume= 1.701 of Primary = 21.76 cfs @ 12.09 hrs, Volume= 1.701 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-1: DP-1 (EX-CB) Hydrograph Inflow 24 2 Primary 23 1.76 cfs 22 Inflow Area=3.377 ac 21 20 - - - - - - - - - - 19 - - - - - - - - - - - 18 17 16 - - - - 15 14 � o UL 10 9 8 7 6 5' 4 3SEW, e 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) PRE-DEVELOPMENT 24-1787EX00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 62 Summary for Link DP-2: DP-2 (OFF-SITE AIRFIELD) Inflow Area = 0.331 ac, 30.92% Impervious, Inflow Depth = 5.74" for 100-yr event Inflow = 2.14 cfs @ 12.09 hrs, Volume= 0.158 of Primary = 2.14 cfs @ 12.09 hrs, Volume= 0.158 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-2: DP-2 (OFF-SITE AIRFIELD) Hydrograph Inflow El ry 2.14 cfs Prima Inflow Area=0.331 ac 2 i i r 01111 U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) Appendix E-Post-Development HydroCAD Report Stormwater Report—LWM Administration Building—492 Sutton Street Page 27 PR-1W PR-3.1 PR-3.1W PR-JE W WATER SURFACE(TO PR-3.1 PR 3.1 PR-3 2 WATER RFACE(TO V A) DA) PR-1 PR-1 P3 SB1 VEGETATED P1-STORMWATER P2 DETENTION 01 BASIN I VE ETATED PR-4.1 ID ENTION 02 I PR-4.1 c6 I 3P I PR-5.1 I F t-J52 D0406( Ilyfish) I PR 5.1 I I PR-5.2 I I I I t-J4.3 I DP-2 I PR-4.3 I DP-2(OFF-SITE AIRFIELD) PR-6 PR-2 DP-1 PR-6 PR-2 DP 1 - B) P R-4.2 TPR-7 PR-4.2 PR-7 PR-8 PR-9 �7-10 PR-11 PR-8 PR-9 PR-10 PR-11 S4ca Reach Pond Link Routing Diagram for 25-0039DVO0_SPR-Rev1 Prepared by McClure, Printed 7/10/2026 HydroCAD®10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC POST-DEVELOPMENT 25-0039 DV00_S P R-Rev1 Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 0.867 74 >75% Grass cover, Good HSG C (PR-1, PR-10, PR-11, PR-2, PR-3.2, PR-5.1) PR-5.2, PR-8, PR-9) 0.658 74 >75% Grass cover, Good, HSG C (PR-10, PR-111 PR-3.1, PR-7) 0.004 98 Concrete (wall/pads) (PR-3-1) 0.049 89 Gravel roads, HSG C (PR-1, PR-3.1) 1.504 98 Paved parking HSG C (PR-1, PR-10, PR-11, PR-2, PR-3.2, PR-5.1, PR-6, PR-7, PR-8, PR-9) 0.001 98 Paved walk (PR-3.1) 0.199 98 Roofs HSG C (PR-10, PR-11, PR-3.1, PR-4.1, PR-4.2, PR-4.3) 0.069 98 Water Surface (as Impervious) (PR-3.1 W) 0.043 98 Water Surface (as impervious) (PR-1 W, PR-3.2W) 0.315 70 Woods, Good HSG C (PR-11, PR-3.1) 3.708 86 TOTAL AREA POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 3 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentPR-1: PR-1 Runoff Area=10,160 sf 36.37% Impervious Runoff Depth=1.65" Tc=6.0 min CN=84 Runoff=0.45 cfs 0.032 of SubcatchmentPR-10: PR-10 Runoff Area=34,216 sf 61.92% Impervious Runoff Depth=2.05" Tc=6.0 min CN=89 Runoff=1.87 cfs 0.134 of SubcatchmentPR-11: PR-11 Runoff Area=23,923 sf 40.23% Impervious Runoff Depth=1.65" Tc=6.0 min CN=84 Runoff=1.06 cfs 0.075 of SubcatchmentPR-1W:WATERSURFACE Runoff Area=1,077 sf 100.00% Impervious Runoff Depth=2.93" Tc=0.0 min CN=98 Runoff=0.09 cfs 0.006 of SubcatchmentPR-2: PR-2 Runoff Area=10,646 sf 85.97% Impervious Runoff Depth=2.61" Tc=6.0 min CN=95 Runoff=0.71 cfs 0.053 of SubcatchmentPR-3.1: PR-3.1 Runoff Area=33,659 sf 1.17% Impervious Runoff Depth=0.96" Flow Length=279' Tc=8.6 min CN=73 Runoff=0.74 cfs 0.062 of SubcatchmentPR-3.1W: PR-3.1 Runoff Area=2,985 sf 100.00% Impervious Runoff Depth=2.93" Tc=0.0 min CN=98 Runoff=0.26 cfs 0.017 of SubcatchmentPR-3.2: PR-3.2 Runoff Area=5,636 sf 74.13% Impervious Runoff Depth=2.31" Tc=6.0 min CN=92 Runoff=0.34 cfs 0.025 of SubcatchmentPR-3.2W:WATERSURFACE Runoff Area=801 sf 100.00% Impervious Runoff Depth=2.93" Tc=0.0 min CN=98 Runoff=0.07 cfs 0.004 of SubcatchmentPR-4.1: PR-4.1 Runoff Area=3,862 sf 100.00% Impervious Runoff Depth=2.93" Tc=6.0 min CN=98 Runoff=0.27 cfs 0.022 of SubcatchmentPR-4.2: PR-4.2 Runoff Area=1,596 sf 100.00% Impervious Runoff Depth=2.93" Tc=6.0 min CN=98 Runoff=0.11 cfs 0.009 of SubcatchmentPR-4.3: PR-4.3 Runoff Area=1,602 sf 100.00% Impervious Runoff Depth=2.93" Tc=6.0 min CN=98 Runoff=0.11 cfs 0.009 of SubcatchmentPR-5.1: PR-5.1 Runoff Area=9,478 sf 31.29% Impervious Runoff Depth=1.51" Tc=6.0 min CN=82 Runoff=0.38 cfs 0.027 of SubcatchmentPR-5.2: PR-5.2 Runoff Area=561 sf 0.00% Impervious Runoff Depth=1.01" Tc=6.0 min CN=74 Runoff=0.01 cfs 0.001 of SubcatchmentPR-6: PR-6 Runoff Area=3,793 sf 100.00% Impervious Runoff Depth=2.93" Tc=6.0 min CN=98 Runoff=0.27 cfs 0.021 of SubcatchmentPR-7: PR-7 Runoff Area=13,728 sf 67.61% Impervious Runoff Depth=2.13" Tc=6.0 min C N=90 Runoff=0.78 cfs 0.056 of POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 4 SubcatchmentPR-8: PR-8 Runoff Area=1,060 sf 81.51% Impervious Runoff Depth=2.51" Tc=6.0 min CN=94 Runoff=0.07 cfs 0.005 of SubcatchmentPR-9: PR-9 Runoff Area=2,728 sf 80.72% Impervious Runoff Depth=2.41" Tc=6.0 min CN=93 Runoff=0.17 cfs 0.013 of Pond 3P: JFPD0406(Jellyfish) Peak Elev=152.96' Inflow=1.85 cfs 0.137 of Primary=0.47 cfs 0.109 of Secondary=1.38 cfs 0.028 of Outflow=1.85 cfs 0.137 of Pond P2: VEGETATED DETENTION 02 Peak EIev=154.09' Storage=56 cf Inflow=0.38 cfs 0.029 of Discarded=0.00 cfs 0.002 of Primary=0.38 cfs 0.027 of Outflow=0.38 cfs 0.029 of Pond P3: VEGETATED DETENTION 01 Peak EIev=154.38' Storage=219 cf Inflow=0.50 cfs 0.038 of Discarded=0.00 cfs 0.007 of Primary=0.48 cfs 0.031 of Outflow=0.48 cfs 0.038 of Pond SB1: P1 -STORMWATERBASIN Peak EIev=157.37' Storage=2,423 cf Inflow=0.83 cfs 0.078 of Discarded=0.02 cfs 0.078 of Primary=0.00 cfs 0.000 of Secondary=0.00 cfs 0.000 of Outflow=0.02 cfs 0.078 of Link DP-1: DP-1 (EX-CB) Inflow=6.29 cfs 0.456 of Primary=6.29 cfs 0.456 of Link DP-2: DP-2(OFF-SITE AIRFIELD) Inflow=0.38 cfs 0.027 of Primary=0.38 cfs 0.027 of Total Runoff Area = 3.708 ac Runoff Volume = 0.571 of Average Runoff Depth = 1.85" 50.93% Pervious = 1.888 ac 49.07% Impervious = 1.819 ac POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment PR-1: PR-1 Runoff = 0.45 cfs @ 12.09 hrs, Volume= 0.032 af, Depth= 1.65" Routed to Pond P3 : VEGETATED DETENTION 01 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 37695 98 Paved parking HSG C 57539 74 >75% Grass cover, Good HSG C 926 89 Gravel roads, HSG C 107160 84 Weighted Average 6,465 63.63% Pervious Area 31695 36.37% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-1: PR-1 Hydrograph 0.5 El Runoff 0.48 0.45 cfs 0.46,1111, 0.44 Type III 24=hr 0.42 0.4 j 2=yr RainfalI=3.16" 0.38 i 0.36 % Runoff Area=10,160 sf 0.34 0.32 / Runoff Volume=0.032 of 0.3 - 0.28 0.26 Runoff Depth=1,65" 0 0.24 0.22 Tc=6.0min 0.18,11`111 CN=84 0.16 0.14 %! - 0.12 r; 0.1 0.08 r f 0.06 0.04 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 6 Summary for Subcatchment PR-10: PR-10 Runoff = 1.87 cfs @ 12.09 hrs, Volume= 0.134 af, Depth= 2.05" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 47033 74 >75% Grass cover, Good, HSG C 695 98 Roofs HSG C 201490 98 Paved parking HSG C 8,998 74 >75% Grass cover, Good HSG C 347216 89 Weighted Average 131031 38.08% Pervious Area 217185 61.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-10: PR-10 Hydrograph 2 1.87 cfs Runoff i Type III 24=hr i j 2=yr Rainfall=3.16" Runoff Area=34 216 sf Runoff Volume=0.134 of Runoff Depth=2.05" 0 Tc=6.O min CN=89 i 0 U U U U U U UU U / 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment PR-11: PR-11 Runoff = 1.06 cfs @ 12.09 hrs, Volume= 0.075 af, Depth= 1.65" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 474 70 Woods, Good HSG C 17340 74 >75% Grass cover, Good, HSG C 8,880 98 Paved parking HSG C 744 98 Roofs HSG C 127485 74 >75% Grass cover, Good HSG C 23,923 84 Weighted Average 141299 59.77% Pervious Area 9,624 40.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-11: PR-11 Hydrograph 1.06 cfs El Runoff Type III 24=hr 1 2=yr Rainfall=3.16" Runoff Area=23,923 sf Runoff Volume=0.075 of % Runoff Depth=1.65 0 Tc=6.0 min CN=84 ................. 12 U U U U U U U U U U U U U TVU-T-P U U U 15 M=�' 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment PR-1W: WATER SURFACE (TO VDA) Runoff = 0.09 cfs @ 12.00 hrs, Volume= 0.006 af, Depth= 2.93" Routed to Pond P3 : VEGETATED DETENTION 01 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 17077 98 Water Surface (as impervious) 17077 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-1 W: WATER SURFACE (TO VDA) Hydrograph 0.1 0.09 cfs El Runoff 0.095 0.09 - - - - - Type III 24=hr 0.085 2=yr Rainfall=3.16" 0.08 - 0.075 - - � - Runoff Area=1,077 sf 0.07 0.065 / Runoff Volume=0.006 of 0.06 0.055 Runoff Depth=2.93" 0.05 ° 0.045 % Tc=0.0 min 0.04 �, 0 CN=98 .035 0.025 ' 0.02 % 0.015 0.01 id r 0.005 014 011 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment PR-2: PR-2 Runoff = 0.71 cfs @ 12.08 hrs, Volume= 0.053 af, Depth= 2.61" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 97152 98 Paved parking HSG C 17494 74 >75% Grass cover, Good HSG C 107646 95 Weighted Average 111494 14.03% Pervious Area 911152 85.97% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-2: PR-2 Hydrograph 0.75 0.71 cfs 0 Runoff 0.7 Type III 24=hr 0.65 0.6 2=yr Rainfall=3.16" 0.55 Runoff Area=10,646 sf 0.5 Runoff Volume=0.053 of 0.45 3 0.4 Runoff Depth=2.61 - Tc=6.0 min O � 0.35 ' 0.3 CN=95 0.2 j 0.15 0.1 0.05 /uo 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 10 Summary for Subcatchment PR-3.1: PR-3.1 Runoff = 0.74 cfs @ 12.13 hrs, Volume= 0.062 af, Depth= 0.96" Routed to Pond S131 : P1 - STORMWATER BASIN Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 131226 70 Woods, Good HSG C 1,199 89 Gravel roads, HSG C 167 98 Concrete (wall/pads) 191 98 Roofs HSG C 35 98 Paved walk 181841 74 >75% Grass cover, Good, HSG C 331659 73 Weighted Average 331266 98.83% Pervious Area 393 1.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.9 33 0.0730 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.74" 2.0 17 0.0250 0.14 Sheet Flow, Grass: Short n= 0.150 P2= 3.74" 1.7 229 0.0200 2.28 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 8.6 279 Total POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 11 Subcatchment PR-3.1: PR-3.1 Hydrograph 0.8 0.74 cfs El Runoff 0.75 Type III 24=hr 0.7 0.65 ,/ � 2=yr Rainfall=3.16" 0.6 i Runoff Area=33,659 sf 0.55 Runoff Volume=0.062 of 0.5 0.45 % Runoff Depth=0.96" 3 0.4 ,0 - - - - - - - - - - Flow Length=279' 0.35 0.3 Tc=8.6 min 0.25 , CN=73 0.2 0.15 i 0.1 0.05 IS 0 U1 U U U U U U U U U U U U U U U U U U U U U U U U U U U U U 1111 1111 1111 1111 1111 1111 11111111 1111 1111 1111 1111 U U U U U U U U U U U U U....U U U U U U U U U U U 1111 11111111 1111 1111 1111 1111 1111 1111 1111 1111 11111111 1111 U U U U U U U U U U U U U U U U U U U U U U U U U U U U 1111 1111 1111 11111111 1111 1111 1111 1111 1111 U U U U U U U U U U U U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 12 Summary for Subcatchment PR-3.1 W: PR-3.1 Runoff = 0.26 cfs @ 12.00 hrs, Volume= 0.017 af, Depth= 2.93" Routed to Pond S131 : P1 - STORMWATER BASIN Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 27985 98 Water Surface (as Impervious) 27985 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-3.1 W: PR-3.1 Hydrograph 0.28 � Runoff 0.26 cfs Type III 24=hr 0.24 0.22111111 2=yr Rainfall=3.16" 0.2 Runoff Area=2,985 sf 0.18 / Runoff Volume=0.017 of Runoff Depth=2.93" 3 0.14 0.12 Tc=0.0 min CN=98 0.04 0.02 01 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 13 Summary for Subcatchment PR-3.2: PR-3.2 Runoff = 0.34 cfs @ 12.09 hrs, Volume= 0.025 af, Depth= 2.31" Routed to Pond P2 : VEGETATED DETENTION 02 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 47178 98 Paved parking HSG C 17458 74 >75% Grass cover, Good HSG C 57636 92 Weighted Average 17458 25.87% Pervious Area 4,178 74.13% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3.2: PR-3.2 Hydrograph 0.38 Runoff 0.36 0.34 cfs El 0.34 - - /, - - - - - - - - - - Type III 24-hr- 0.32 0.3 % 2=yr Rainfall=3.16" 0.28 0.26 Runoff Area=5,636 sf 0.24 Runoff Volume=0.025 of 0.22 - - - - - - - - - - - - - 0.2 Runoff Depth=2.31 0 0.1 s • - Tc=6.0 m i n 0.14 CN=92 0.12 0.1 0.08 0.06 0.04 0.02 0 ,,,i,,; 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 14 Summary for Subcatchment PR-3.2W: WATER SURFACE (TO VDA) Runoff = 0.07 cfs @ 12.00 hrs, Volume= 0.004 af, Depth= 2.93" Routed to Pond P2 : VEGETATED DETENTION 02 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 801 98 Water Surface (as impervious) 801 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-3.2W: WATER SURFACE (TO VDA) Hydrograph El if 0.075 0.07 cfs Runo 0.07 Type III 24=hr 0.065 0.06 2=yr Rainfall=3.16" 0.055 Runoff Area=801 sf Runoff Volume=0.004 of 0.045 0.04 j Runoff Depth=2.93" 3 ,� 0.035 /// Tc=0,0 min 0.03 CN=98- 51111111 0.01 , 0.005 ; � 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 15 Summary for Subcatchment PR-4.1: PR-4.1 Runoff = 0.27 cfs @ 12.08 hrs, Volume= 0.022 af, Depth= 2.93" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 37862 98 Roofs H S G C 37862 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.1: PR-4.1 Hydrograph 0.3 � Runoff 0.27 cfs 0.28 Type III 24=hr 0.26 0.24 / 2=yr Rainfall=3.16" Runoff Area=3,862 sf Runoff Volume=0.022 of 0.18 0.16 %.o Runoff Depth=2.93" 0 0.14 Tc=6.0 min i, CN=98 0.1 j 0.08 0.04 0.02 0 0 2 4 6 8 10 12 14 16 1820 2224 2628 3032 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 16 Summary for Subcatchment PR-4.2: PR-4.2 Runoff = 0.11 cfs @ 12.08 hrs, Volume= 0.009 af, Depth= 2.93" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 17596 98 Roofs H S G C 17596 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.2: PR-4.2 Hydrograph 0.125 El Runoff 0.12 0.11 cfs 0.115 0.11 / Type III 24=hr .1 0 05 0.11 G - - - 2=yr Rainfall=3.16" 0.095 0.09 - - - Runoff Area=1,596 sf 0.085 0.08 Runoff Volume=0.009 of 0.075 4 0.07-0.065 Runoff Depth=2.93" 9:0.055 % Tc=6.0 rain 0.05 - % - - - - - - CN=98 0.025 0.02 �'' 0.015 - - - - - - - - 0.01 0.005 0 M? E/ , 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 4446 4850 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 17 Summary for Subcatchment PR-4.3: PR-4.3 Runoff = 0.11 cfs @ 12.08 hrs, Volume= 0.009 af, Depth= 2.93" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 17602 98 Roofs H S G C 17602 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.3: PR-4.3 Hydrograph 0.125 El Runoff 0.12 0.11 cfs 0.115 0.11 / Type III 24=hr 0.105 0.11 / 2=yr Rainfall=3.16" 0.095 G 0.09`"" Runoff Area-1,602 sf 0.085 0.08 Runoff Volume=0.009 of 075,11111111 4 0.07 `% --0.065 Runoff Depth=2.93" 0 0.06 Tc=6.0 min 9:0.055 0.05 0.045 CN=98 0.035 - 0.03 0.025 0.02 0.015 0.01 0.005 ' r. 'i 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 18 Summary for Subcatchment PR-5.1: PR-5.1 Runoff = 0.38 cfs @ 12.09 hrs, Volume= 0.027 af, Depth= 1.51" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 27966 98 Paved parking HSG C 67512 74 >75% Grass cover, Good HSG C 97478 82 Weighted Average 67512 68.71% Pervious Area 2,966 31.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5.1: PR-5.1 Hydrograph 0.42 Runoff 0.4 0.38 cfs 0.38Type% III 24=hr 0.36 / 0.34 2=yr Rainfall=3.16" 0.32 0.3 % Runoff Area=9,478 sf 0.26 / Runoff Volume=0.027 of 0.24 0.22 Runoff Depth=1,51 Tc 6.0 min 0.2 0.18 CN=82 0.14 0.12 0.1 0.060.04 - "' 0.02 �,,,ENi r 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 19 Summary for Subcatchment PR-5.2: PR-5.2 Runoff = 0.01 cfs @ 12.10 hrs, Volume= 0.001 af, Depth= 1.01" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 561 74 >75% Grass cover, Good HSG C 561 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5.2: PR-5.2 Hydrograph 0.016 El Runoff 0.01 cfs 0.015 0.014 ' Type III 24=hr 0.013 j 2=yr Rainfall=3.16" 211111111111111 0.011 Runoff Area=561 sf 0.01 , Runoff Volume=0.001 of 14 0.009 Runoff Depth=1.01 3 0.008 9: 0.007 Tc=6,0 min 0.006 CN=74 0.005 0.0041111111' 0.003 0.002 0.001 a'r,/„ r,,,,,,i,/i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 20 Summary for Subcatchment PR-6: PR-6 Runoff = 0.27 cfs @ 12.08 hrs, Volume= 0.021 af, Depth= 2.93" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 37793 98 Paved parking HSG C 37793 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-6: PR-6 Hydrograph 0.28 0.27 cfs 0 Runoff 0.26 Type III 24=hr 0.24 2=yr Rainfall'=3.16" 0.22 Runoff Area=3,793 sf 0.1 Runoff Volume=0.021 of 8 Runoff Depth=2.93" 0 0.14 - Tc=6.0 min i CN=98 0.04 0.06 0UP ,,,,,, ,'"„/'a 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 21 Summary for Subcatchment PR-7: PR-7 Runoff = 0.78 cfs @ 12.09 hrs, Volume= 0.056 af, Depth= 2.13" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 97281 98 Paved parking HSG C 47447 74 >75% Grass cover, Good, HSG C 137728 90 Weighted Average 4,447 32.39% Pervious Area 9,281 67.61% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-7: PR-7 Hydrograph El Runoff 0.85 0.78 cfs 0.8 0.75 ,� Type....III 24=hr � 0.7 2=yr Rainfall=3.16" 0.65 _Runoff Area=13,728 sf 0.55 Runoff Volume=0.056 of 0.5 ',! 0.45 % Runoff Depth=2.13" c 0.4UL / Tc=6.0 min 0.35 %% - - - - - - - - - CN=90 0.25 0.2 0.15 0.1 0.05 ' 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 22 Summary for Subcatchment PR-8: PR-8 Runoff = 0.07 cfs @ 12.08 hrs, Volume= 0.005 af, Depth= 2.51" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 864 98 Paved parking HSG C 196 74 >75% Grass cover, Good HSG C 17060 94 Weighted Average 196 18.49% Pervious Area 864 81.51% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-8: PR-8 Hydrograph 0.075 El Runoff 0.07 cfs 0.07 �0.065 Type III 24-hr � 0.06 2=yr Rainfall=3.16' 0.05511111111 Runoff Area=1,060sf Runoff Volume=0.005 of 0.045 o 0.04 Runoff Depth=2.51 �� c 0.035 Tc=6,0 min 0.03 CN=94 0.025 !% 0.02 0.015 0.01 0.005 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 23 Summary for Subcatchment PR-9: PR-9 Runoff = 0.17 cfs @ 12.09 hrs, Volume= 0.013 af, Depth= 2.41" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 2-yr Rainfall=3.16" Area (sf) CN Description 27202 98 Paved parking HSG C 526 74 >75% Grass cover, Good HSG C 27728 93 Weighted Average 526 19.28% Pervious Area 2,202 80.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-9: PR-9 Hydrograph 0.19 � � E Runoff 0.18 0.17 cfs 0.17 - - /, - - - - - - - - - - Type 0.16 III 24-hr- 0.15 2=yr RainfalI=3.16" � 0.14 Runoff Area=2 728 sf 0.13 0.12 Runoff Volume=0.013 of 0.11 0.1 Runoff Depth=2.41" 0 0.09 9: 0.08, Tc=6.0 min 0.07 CN=93 0.06 0.05 0.04 0.03 0.02 0.01 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 24 Summary for Pond 3P: JFPD0406 (Jellyfish) Inflow Area = 0.728 ac, 73.12% Impervious, Inflow Depth = 2.26" for 2-yr event Inflow = 1.85 cfs @ 12.09 hrs, Volume= 0.137 of Outflow = 1.85 cfs @ 12.09 hrs, Volume= 0.137 af, Atten= 0%, Lag= 0.0 min Primary = 0.47 cfs @ 11.78 hrs, Volume= 0.109 of Routed to Link DP-1 : DP-1 (EX-CB) Secondary= 1.38 cfs @ 12.09 hrs, Volume= 0.028 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 152.96'@ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 150.90' JF CSV File Head (feet) 0.00 0.08 0.17 0.25 0.33 0.42 0.50 0.58 0.67 0.75 0.83 0.92 1.00 1.08 1.17 1.25 1.33 1.42 1.50 1.58 1.67 1.75 Disch. (cfs) 0.000 0.003 0.006 0.010 0.013 0.016 0.019 0.049 0.079 0.109 0.139 0.169 0.199 0.229 0.258 0.288 0.318 0.348 0.378 0.408 0.438 0.468 #2 Secondary 152.65' 2.8' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 Primary OutFlow Max=0.47 cfs @ 11.78 hrs HW=152.66' (Free Discharge) L1=JF CSV File (Custom Controls 0.47 cfs) Secondary OutFlow Max=1.38 cfs @ 12.09 hrs HW=152.96' (Free Discharge) L2=Broad-Crested Rectangular Weir(Weir Controls 1.38 cfs @ 1.59 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 25 Pond 3P: JFPD0406 (Jellyfish) Hydrograph 1 1.85 cfs Inflow 1.85 cfs II llll outflow Primary � Inflow Area=0.728 ac El Secondary 2 Peak Elev=152.96' 1.38 cfs 402 3 1 � o cfs o s 0 2 4 6 8 10 1214 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 26 Stage-Area-Storage for Pond 3P: JFPD0406 (Jellyfish) Elevation Storage Elevation Storage Elevation Storage (feet) (acre-feet) (feet) (acre-feet) (feet) (acre-feet) 150.90 0.000 151.92 0.000 152.94 0.000 150.92 0.000 151.94 0.000 152.96 0.000 150.94 0.000 151.96 0.000 150.96 0.000 151.98 0.000 150.98 0.000 152.00 0.000 151.00 0.000 152.02 0.000 151.02 0.000 152.04 0.000 151.04 0.000 152.06 0.000 151.06 0.000 152.08 0.000 151.08 0.000 152.10 0.000 151.10 0.000 152.12 0.000 151.12 0.000 152.14 0.000 151.14 0.000 152.16 0.000 151.16 0.000 152.18 0.000 151.18 0.000 152.20 0.000 151.20 0.000 152.22 0.000 151.22 0.000 152.24 0.000 151.24 0.000 152.26 0.000 151.26 0.000 152.28 0.000 151.28 0.000 152.30 0.000 151.30 0.000 152.32 0.000 151.32 0.000 152.34 0.000 151.34 0.000 152.36 0.000 151.36 0.000 152.38 0.000 151.38 0.000 152.40 0.000 151.40 0.000 152.42 0.000 151.42 0.000 152.44 0.000 151.44 0.000 152.46 0.000 151.46 0.000 152.48 0.000 151.48 0.000 152.50 0.000 151.50 0.000 152.52 0.000 151.52 0.000 152.54 0.000 151.54 0.000 152.56 0.000 151.56 0.000 152.58 0.000 151.58 0.000 152.60 0.000 151.60 0.000 152.62 0.000 151.62 0.000 152.64 0.000 151.64 0.000 152.66 0.000 151.66 0.000 152.68 0.000 151.68 0.000 152.70 0.000 151.70 0.000 152.72 0.000 151.72 0.000 152.74 0.000 151.74 0.000 152.76 0.000 151.76 0.000 152.78 0.000 151.78 0.000 152.80 0.000 151.80 0.000 152.82 0.000 151.82 0.000 152.84 0.000 151.84 0.000 152.86 0.000 151.86 0.000 152.88 0.000 151.88 0.000 152.90 0.000 151.90 0.000 152.92 0.000 POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 27 Summary for Pond P2: VEGETATED DETENTION 02 nflow Area = 0.989 ac, 19.40% Impervious, Inflow Depth = 0.36" for 2-yr event Inflow = 0.38 cfs @ 12.08 hrs, Volume= 0.029 of Outflow = 0.38 cfs @ 12.09 hrs, Volume= 0.029 af, Atten= 0%, Lag= 0.5 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.002 of Primary = 0.38 cfs @ 12.09 hrs, Volume= 0.027 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 154.09'@ 12.09 hrs Surf.Area= 175 sf Storage= 56 cf Plug-Flow detention time=46.8 min calculated for 0.029 of(100% of inflow) Center-of-Mass det. time=46.8 min ( 837.8 - 791.0 ) Volume Invert Avail.Storage Storage Description #1 153.60' 316 cf Custom Stage Data (Irregular)Listed below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 153.60 56 40.0 0 0 56 154.00 156 56.0 41 41 180 155.00 416 117.0 276 316 15024 Device Routing Invert Outlet Devices #1 Device 2 154.00' 15.0" Horiz. 15" GRATE C= 0.600 Limited to weir flow at low heads #2 Primary 152.10' 12.0" Round 12" HDPE L= 21.7' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 152.10'/ 151.10' S= 0.0461 T Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.79 sf #3 Discarded 153.60' 0.270 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=154.09' (Free Discharge) L3=Exfi1tration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=0.37 cfs @ 12.09 hrs HW=154.09' (Free Discharge) L2=12" HDPE (Passes 0.37 cfs of 3.65 cfs potential flow) L1=15" GRATE (Weir Controls 0.37 cfs @ 1.01 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 28 Pond P2: VEGETATED DETENTION 02 Hydrograph 0.38 cfsj EM Inflow 0.38 cfs `� I uuullll Outflow 0.42 Inflow Area=0.989 ac Discarded Primary 0.4 0.38 cfs 0.38 Peak Elev=154.09' 0.36 Storage=56 cf 0.34 0.32 0.28 0.26 / 42) 0.24 - 0.22 3 0.2 M 0.18 0.16 0.14 0.12 0.1 -� - - - - - - - -0.06 ,r cfs 0 2 4 6 8 10 12 1416 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 29 Stage-Area-Storage for Pond P2: VEGETATED DETENTION 02 Elevation Surface Storage Elevation Surface Storage (feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet) 153.60 56 0 154.62 302 180 153.62 60 1 154.64 308 186 153.64 64 2 154.66 314 193 153.66 68 4 154.68 319 199 153.68 72 5 154.70 325 205 153.70 76 7 154.72 331 212 153.72 81 8 154.74 336 219 153.74 85 10 154.76 342 225 153.76 90 12 154.78 348 232 153.78 95 13 154.80 354 239 153.80 100 15 154.82 360 247 153.82 105 17 154.84 366 254 153.84 110 20 154.86 372 261 153.86 115 22 154.88 378 269 153.88 121 24 154.90 384 276 153.90 126 27 154.92 391 284 153.92 132 29 154.94 397 292 153.94 138 32 154.96 403 300 153.96 144 35 154.98 410 308 153.98 150 38 155.00 416 316 154.00 156 41 154.02 160 44 154.04 164 47 154.06 168 50 154.08 172 54 154.10 176 57 154.12 181 61 154.14 185 65 154.16 189 68 154.18 194 72 154.20 198 76 154.22 202 80 154.24 207 84 154.26 212 88 154.28 216 93 154.30 221 97 154.32 226 101 154.34 230 106 154.36 235 111 154.38 240 115 154.40 245 120 154.42 250 125 154.44 255 130 154.46 260 135 154.48 265 141 154.50 270 146 154.52 276 151 154.54 281 157 154.56 286 163 154.58 292 168 154.60 297 174 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 30 Summary for Pond P3: VEGETATED DETENTION 01 Inflow Area = 0.258 ac, 42.47% Impervious, Inflow Depth = 1.77" for 2-yr event Inflow = 0.50 cfs @ 12.08 hrs, Volume= 0.038 of Outflow = 0.48 cfs @ 12.10 hrs, Volume= 0.038 af, Atten= 2%, Lag= 1.2 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.007 of Primary = 0.48 cfs @ 12.10 hrs, Volume= 0.031 of Routed to Pond 3P : J FPD0406 (Jellyfish) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 154.38'@ 12.10 hrs Surf.Area= 397 sf Storage= 219 cf Plug-Flow detention time= 166.1 min calculated for 0.038 of(100% of inflow) Center-of-Mass det. time= 166.3 min ( 983.9 - 817.6 ) Volume Invert Avail.Storage Storage Description #1 153.60' 540 cf VEGETATED DETENTION 01 (Irregullar�isted below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 153.60 195 58.0 0 0 195 154.00 272 65.0 93 93 268 155.00 650 162.0 447 540 25024 Device Routing Invert Outlet Devices #1 Device 2 154.25' 12.0" Horiz. 12" AD (Orifice/Grate) C= 0.600 Limited to weir flow at low heads #2 Primary 152.00' 10.0" Round 10" HDPE L= 48.1' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 152.00'/ 151.51' S= 0.0102 7' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #3 Discarded 153.60' 0.270 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=154.38' (Free Discharge) L3=Exfi1tration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=0.48 cfs @ 12.10 hrs HW=154.38' (Free Discharge) L2=10" HDPE (Passes 0.48 cfs of 2.90 cfs potential flow) L1=12" AD (Orifice/Grate)(Weir Controls 0.48 cfs @ 1.18 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 31 Pond P3: VEGETATED DETENTION 01 Hydrograph ---------------------------------------------------------- 0.50 cfs Inflow II llll Outflow 0.48 cfs II Discarded 0.55 Inflow Area=0.258 ac Primary 0.48 cfs Peak Elev=154.38' 0.5 Storage=219 cf 0.4 0.35 03 o UL 0.25 0.2 0.15 0. i 1 cfs 1 0 2 4 6 8 10 12 1416 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 32 Stage-Area-Storage for Pond P3: VEGETATED DETENTION 01 Elevation Surface Storage Elevation Surface Storage (feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet) 153.60 195 0 154.62 487 325 153.62 199 4 154.64 495 335 153.64 202 8 154.66 503 345 153.66 206 12 154.68 511 355 153.68 209 16 154.70 520 365 153.70 213 20 154.72 528 376 153.72 217 25 154.74 536 387 153.74 220 29 154.76 544 397 153.76 224 34 154.78 553 408 153.78 228 38 154.80 561 419 153.80 232 43 154.82 570 431 153.82 236 47 154.84 579 442 153.84 240 52 154.86 587 454 153.86 244 57 154.88 596 466 153.88 248 62 154.90 605 478 153.90 252 67 154.92 614 490 153.92 256 72 154.94 623 502 153.94 260 77 154.96 632 515 153.96 264 82 154.98 641 528 153.98 268 88 155.00 650 540 154.00 272 93 154.02 278 98 154.04 284 104 154.06 290 110 154.08 296 116 154.10 303 122 154.12 309 128 154.14 315 134 154.16 322 140 154.18 328 147 154.20 335 154 154.22 341 160 154.24 348 167 154.26 355 174 154.28 362 181 154.30 368 189 154.32 375 196 154.34 382 204 154.36 389 211 154.38 397 219 154.40 404 227 154.42 411 235 154.44 418 244 154.46 426 252 154.48 433 261 154.50 441 269 154.52 448 278 154.54 456 287 154.56 464 297 154.58 471 306 154.60 479 315 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 33 Summary for Pond SB1: P1 - STORMWATER BASIN Inflow Area = 0.841 ac, 9.22% Impervious, Inflow Depth = 1.12" for 2-yr event Inflow = 0.83 cfs @ 12.13 hrs, Volume= 0.078 of Outflow = 0.02 cfs @ 21.58 hrs, Volume= 0.078 af, Atten= 98%, Lag= 566.8 min Discarded = 0.02 cfs @ 21.58 hrs, Volume= 0.078 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routed to Pond P2 : VEGETATED DETENTION 02 Secondary= 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 157.37'@ 21.58 hrs Surf.Area= 3,191 sf Storage= 2,423 cf Plug-Flow detention time= 1,246.1 min calculated for 0.078 of(100% of inflow) Center-of-Mass det. time= 1,246.3 min ( 2,089.8 - 843.6 ) Volume Invert Avail.Storage Storage Description #1 156.50' 7,085 cf Basin (Irregular)Listed below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 156.50 21369 226.0 0 0 25369 157.00 21834 239.0 15299 15299 25864 158.00 33838 264.0 35323 45622 35896 158.60 43378 276.0 25463 75085 45436 Device Routing Invert Outlet Devices #1 Discarded 156.50' 0.270 in/hr Infiltration over Surface area #2 Primary 157.50' 12.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 #3 Device 4 157.60' 1.0" x 9.0" Horiz. 12" Orifice/Grate X 8.00 C= 0.600 in 12.0" Grate (64% open area) Limited to weir flow at low heads #4 Secondary 153.00' 12.0" Round 12" HDPE L= 50.4' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 153.00'/ 152.00' S= 0.0198 7' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 34 Discarded OutFlow Max=0.02 cfs @ 21.58 hrs HW=157.37' (Free Discharge) L1=Infiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=156.50' (Free Discharge) L2=Broad-Crested Rectangular Weir( Controls 0.00 cfs) Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=156.50' (Free Discharge) L4=12" HDPE (Passes 0.00 cfs of 5.17 cfs potential flow) L3=12" Orifice/Grate ( Controls 0.00 cfs) Pond SB1: P1 - STORMWATER BASIN Hydrograph ---------------------------------------------------------- 0.83 cfs EM Inflow IIII llll Outflow Inflow Area=0.841 ac MDiscarded Primary 0.9 Peak Elev=157.37' Secondar y 0.85 0.8 Storage=2,423 cf, 0.75 0.7 0.65 0.6 y 0.55 ,.. 0.5 3 0.45 0 0.4 0.35 0.3 0.25 0.02 cfs 0.2 0.02 cfs 0.1 0.00 cfs 0.00 cfs 0 0 2 4 6 8 1012 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 35 Stage-Area-Storage for Pond SB1: P1 - STORMWATER BASIN Elevation Surface Storage (feet) (sq-ft) (cubic-feet) 156.50 23369 0 156.55 23414 120 156.60 23459 241 156.65 23504 365 156.70 23550 492 156.75 2596 620 156.80 2)643 751 156.85 25690 885 156.90 23738 1,020 156.95 23786 11159 157.00 23834 1,299 157.05 23881 1,442 157.10 23928 1587 157.15 23975 1,735 157.20 3,023 11885 157.25 3,071 2,037 157.30 33119 2,192 157.35 33168 2,349 157.40 33217 21508 157.45 33267 2,671 157.50 33317 2,835 157.55 33367 3,002 157.60 33418 3,172 157.65 3,469 31344 157.70 3521 3519 157.75 33573 3,696 157.80 33625 3,876 157.85 33678 41059 157.90 33731 4,244 157.95 33784 4,432 158.00 33838 4,622 158.05 33882 4,815 158.10 3,926 51011 158.15 3,970 5,208 158.20 43014 5,407 158.25 43059 5,609 158.30 43104 51813 158.35 43149 6,020 158.40 43194 6,228 158.45 43240 6,439 158.50 43286 6,652 158.55 4,332 61868 158.60 41378 77085 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 36 Summary for Link DP-1: DP-1 (EX-CB) Inflow Area = 3.490 ac, 50.18% Impervious, Inflow Depth = 1.57" for 2-yr event Inflow = 6.29 cfs @ 12.09 hrs, Volume= 0.456 of Primary = 6.29 cfs @ 12.09 hrs, Volume= 0.456 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-1: DP-1 (EX-CB) Hydrograph Inflow 7 E Primary 6.29 cfs j Inflow Area=3.490 ac 6 5 3 2 '! 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 2-yr Rainfall=3.16" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 37 Summary for Link DP-2: DP-2 (OFF-SITE AIRFIELD) Inflow Area = 0.218 ac, 31.29% Impervious, Inflow Depth = 1.51" for 2-yr event Inflow = 0.38 cfs @ 12.09 hrs, Volume= 0.027 of Primary = 0.38 cfs @ 12.09 hrs, Volume= 0.027 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-2: DP-2 (OFF-SITE AIRFIELD) Hydrograph Inflow 0.42 Prima s ry 0.38 cf 0.4 Inflow Area=0.218 ac 0.38 0.36 0.34 0.32 - 0.3 0.28 0.18 ' 0.16 0.14 'i - 0.12 0.1 0.08 0.06 0.04 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 38 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentPR-1: PR-1 Runoff Area=10,160 sf 36.37% Impervious Runoff Depth=3.27" Tc=6.0 min CN=84 Runoff=0.89 cfs 0.064 of SubcatchmentPR-10: PR-10 Runoff Area=34,216 sf 61.92% Impervious Runoff Depth=3.77" Tc=6.0 min CN=89 Runoff=3.37 cfs 0.247 of SubcatchmentPR-11: PR-11 Runoff Area=23,923 sf 40.23% Impervious Runoff Depth=3.27" Tc=6.0 min CN=84 Runoff=2.09 cfs 0.150 of SubcatchmentPR-1W:WATERSURFACE Runoff Area=1,077 sf 100.00% Impervious Runoff Depth=4.76" Tc=0.0 min CN=98 Runoff=0.15 cfs 0.010 of SubcatchmentPR-2: PR-2 Runoff Area=10,646 sf 85.97% Impervious Runoff Depth=4.42" Tc=6.0 min C N=95 Runoff=1.16 cfs 0.090 of SubcatchmentPR-3.1: PR-3.1 Runoff Area=33,659 sf 1.17% Impervious Runoff Depth=2.28" Flow Length=279' Tc=8.6 min CN=73 Runoff=1.87 cfs 0.147 of SubcatchmentPR-3.1W: PR-3.1 Runoff Area=2,985 sf 100.00% Impervious Runoff Depth=4.76" Tc=0.0 min CN=98 Runoff=0.41 cfs 0.027 of SubcatchmentPR-3.2: PR-3.2 Runoff Area=5,636 sf 74.13% Impervious Runoff Depth=4.09" Tc=6.0 min CN=92 Runoff=0.59 cfs 0.044 of SubcatchmentPR-3.2W:WATERSURFACE Runoff Area=801 sf 100.00% Impervious Runoff Depth=4.76" Tc=0.0 min CN=98 Runoff=0.11 cfs 0.007 of SubcatchmentPR-4.1: PR-4.1 Runoff Area=3,862 sf 100.00% Impervious Runoff Depth=4.76" Tc=6.0 min CN=98 Runoff=0.43 cfs 0.035 of SubcatchmentPR-4.2: PR-4.2 Runoff Area=1,596 sf 100.00% Impervious Runoff Depth=4.76" Tc=6.0 min CN=98 Runoff=0.18 cfs 0.015 of SubcatchmentPR-4.3: PR-4.3 Runoff Area=1,602 sf 100.00% Impervious Runoff Depth=4.76" Tc=6.0 min CN=98 Runoff=0.18 cfs 0.015 of SubcatchmentPR-5.1: PR-5.1 Runoff Area=9,478 sf 31.29% Impervious Runoff Depth=3.08" Tc=6.0 min CN=82 Runoff=0.78 cfs 0.056 of SubcatchmentPR-5.2: PR-5.2 Runoff Area=561 sf 0.00% Impervious Runoff Depth=2.36" Tc=6.0 min CN=74 Runoff=0.04 cfs 0.003 of SubcatchmentPR-6: PR-6 Runoff Area=3,793 sf 100.00% Impervious Runoff Depth=4.76" Tc=6.0 min CN=98 Runoff=0.43 cfs 0.035 of SubcatchmentPR-7: PR-7 Runoff Area=13,728 sf 67.61% Impervious Runoff Depth=3.88" Tc=6.0 min CN=90 Runoff=1.38 cfs 0.102 of POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 39 SubcatchmentPR-8: PR-8 Runoff Area=1,060 sf 81.51% Impervious Runoff Depth=4.31" Tc=6.0 min CN=94 Runoff=0.11 cfs 0.009 of SubcatchmentPR-9: PR-9 Runoff Area=2,728 sf 80.72% Impervious Runoff Depth=4.20" Tc=6.0 min CN=93 Runoff=0.29 cfs 0.022 of Pond 3P: JFPD0406(Jellyfish) Peak Elev=153.12' Inflow=3.17 cfs 0.243 of Primary=0.47 cfs 0.172 of Secondary=2.70 cfs 0.071 of Outflow=3.17 cfs 0.243 of Pond P2: VEGETATED DETENTION 02 Peak Elev=154.18' Storage=72 cf Inflow=0.96 cfs 0.133 of Discarded=0.00 cfs 0.003 of Primary=0.96 cfs 0.131 of Outflow=0.96 cfs 0.133 of Pond P3: VEGETATED DETENTION 01 Peak Elev=154.45' Storage=249 cf Inflow=0.96 cfs 0.073 of Discarded=0.00 cfs 0.007 of Primary=0.94 cfs 0.066 of Outflow=0.94 cfs 0.073 of Pond SB1: P1 -STORMWATERBASIN Peak Elev=157.59' Storage=3,139 cf Inflow=2.03 cfs 0.174 of Discarded=0.02 cfs 0.092 of Primary=0.78 cfs 0.082 of Secondary=0.00 cfs 0.000 of Outflow=0.80 cfs 0.174 of Link DP-1: DP-1 (EX-CB) Inflow=11.24 cfs 0.917 of Primary=11.24 cfs 0.917 of Link DP-2: DP-2(OFF-SITE AIRFIELD) Inflow=0.78 cfs 0.056 of Primary=0.78 cfs 0.056 of Total Runoff Area = 3.708 ac Runoff Volume = 1.075 of Average Runoff Depth = 3.48" 50.93% Pervious = 1.888 ac 49.07% Impervious = 1.819 ac POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 40 Summary for Subcatchment PR-1: PR-1 Runoff = 0.89 cfs @ 12.09 hrs, Volume= 0.064 af, Depth= 3.27" Routed to Pond P3 : VEGETATED DETENTION 01 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 37695 98 Paved parking HSG C 57539 74 >75% Grass cover, Good HSG C 926 89 Gravel roads, HSG C 107160 84 Weighted Average 6,465 63.63% Pervious Area 31695 36.37% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-1: PR-1 Hydrograph 0.95 0.89 cfs El Runoff 0.9 o.85 Type III 24=hr % 0.810=yr Rainfall=5.00" 0.75 0.7 Runoff Area=10,160 sf 00.6 ' Runoff Volume=0.064 of 0.55 Runoff Depth=3,27" 3.1 0.5 0 0.45 Tc=6.0-rain 0.4 0.35 CN=84 0.3 0.2 � j 0.15 0.1 0.05 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 41 Summary for Subcatchment PR-1 0: PR-10 Runoff = 3.37 cfs @ 12.09 hrs, Volume= 0.247 af, Depth= 3.77" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 47033 74 >75% Grass cover, Good, HSG C 695 98 Roofs HSG C 201490 98 Paved parking HSG C 8,998 74 >75% Grass cover, Good HSG C 347216 89 Weighted Average 131031 38.08% Pervious Area 217185 61.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-10: PR-10 Hydrograph 3.37 cfs El Runoff % Type III 24=hr j 10=yr Rainfall=5.00" 3 Runoff Area=34,216 sf Runoff Volume=0.247 of 2 / Runoff Depth=3,77" 0 Tc=6.0 min CN=89 1 0 / rrriijjpripi 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 3840 42 44 46 48 50 52 54 56 58 60 62 6466 6870 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 42 Summary for Subcatchment PR-11: PR-11 Runoff = 2.09 cfs @ 12.09 hrs, Volume= 0.150 af, Depth= 3.27" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 474 70 Woods, Good HSG C 17340 74 >75% Grass cover, Good, HSG C 8,880 98 Paved parking HSG C 744 98 Roofs HSG C 127485 74 >75% Grass cover, Good HSG C 23,923 84 Weighted Average 141299 59.77% Pervious Area 9,624 40.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-11: PR-11 Hydrograph 2.09 cfs El Runoff Type III 24=hr 2 / 10=yr Rainfall=5.00" Runoff Area=23,923 sf y Runoff Volume=0.150 of Runoff Depth=3.27" o UL Tc=6.0 min- CN=84 0 U U U U U U UU U U U U U U U U UU U U U U U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 111 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 43 Summary for Subcatchment PR-1W: WATER SURFACE (TO VDA) Runoff = 0.15 cfs @ 12.00 hrs, Volume= 0.010 af, Depth= 4.76" Routed to Pond P3 : VEGETATED DETENTION 01 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 17077 98 Water Surface (as impervious) 17077 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-1 W: WATER SURFACE (TO VDA) Hydrograph 0.16 0.15 cfs El Runoff 0.15 � 0.14 Type III 24=hr � 0.13 10=yr Rainfall=5.00" 0.12 Runoff Area=1,077 sf 0.1 Runoff Volume=0.010 of 0.09 Runoff Depth=4,76" 3 0.08 . 0.07 Tc=0.0min 0.06 CN=98 j 0.04 0.03 0.02 0.01 01 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 44 Summary for Subcatchment PR-2: PR-2 Runoff = 1.16 cfs @ 12.08 hrs, Volume= 0.090 af, Depth= 4.42" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 97152 98 Paved parking HSG C 17494 74 >75% Grass cover, Good HSG C 107646 95 Weighted Average 1,494 14.03% Pervious Area 9,152 85.97% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-2: PR-2 Hydrograph 1.16 cfs El Runoff Type III 24=hr / 10=yr Rainfall=5.00" Runoff Area=10,646 sf Runoff Volume=0.090 of j Runoff Depth=4.42" 0 Tc=6.0 min CN=95 r „ O %'/n U I I I I U I I I I U I I MrITITrm"pr I U U U U U U U U U U U U TTYrFrv-FTTJFTTTTJFVTTTTlIF71171IF7117711711511 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 45 Summary for Subcatchment PR-3.1: PR-3.1 Runoff = 1.87 cfs @ 12.13 hrs, Volume= 0.147 af, Depth= 2.28" Routed to Pond S131 : P1 - STORMWATER BASIN Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 131226 70 Woods, Good HSG C 1,199 89 Gravel roads, HSG C 167 98 Concrete (wall/pads) 191 98 Roofs HSG C 35 98 Paved walk 181841 74 >75% Grass cover, Good, HSG C 331659 73 Weighted Average 331266 98.83% Pervious Area 393 1.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.9 33 0.0730 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.74" 2.0 17 0.0250 0.14 Sheet Flow, Grass: Short n= 0.150 P2= 3.74" 1.7 229 0.0200 2.28 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 8.6 279 Total POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 46 Subcatchment PR-3.1: PR-3.1 Hydrograph 2 1.87 cfs El Runoff o Type III 24=hr 10=yr Rainfall=5.00" Runoff Area=33,659 sf Runoff Volume=0.147 of Runoff Depth=2.28" 0 3 1 Flow Length=279' Tc=8.6 min r %r CN=73 f 0 u u j 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 111 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 47 Summary for Subcatchment PR-3.1 W: PR-3.1 Runoff = 0.41 cfs @ 12.00 hrs, Volume= 0.027 af, Depth= 4.76" Routed to Pond S131 : P1 - STORMWATER BASIN Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 27985 98 Water Surface (as Impervious) 27985 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-3.1 W: PR-3.1 Hydrograph if 0.44 0.41 cfs E Run o 0.42 - - - - - - -0.4 - - - - - Type III 24=hr 0.38 -- 0.36 y % 10- r Rainfall=5.00" � - 0.32 Runoff Area=12,985 sf 0.3 Runoff Volume=0.027 of ........ 0.26 0.24 Runoff Depth=4,76" 3 0.22 0 - 0.2 - % Tc=0.0 min � 0.18 0.16,11 CN=98 0.14 - 0.12 0.1 - - - - - - - - - - - - 0.08 r 0.06 - 0.04 - �, 0.02 / 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 48 Summary for Subcatchment PR-3.2: PR-3.2 Runoff = 0.59 cfs @ 12.08 hrs, Volume= 0.044 af, Depth= 4.09" Routed to Pond P2 : VEGETATED DETENTION 02 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 47178 98 Paved parking HSG C 17458 74 >75% Grass cover, Good HSG C 57636 92 Weighted Average 17458 25.87% Pervious Area 4,178 74.13% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3.2: PR-3.2 Hydrograph 0.65 � Runoff 0.59 cfs 0.6 '% Type..III 24=hr 0.55 0.5 10=yr Rainfall=5.00" 0.45 Runoff Area=5 636 sf 0.4 Runoff Volume=0.044 of 0.35 % Runoff Depth=4.09" 3 0.3 UL Tc=6.0 min r 0.25 CN=92 0.2 0.15 0.10.05 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 49 Summary for Subcatchment PR-3.2W: WATER SURFACE (TO VDA) Runoff = 0.11 cfs @ 12.00 hrs, Volume= 0.007 af, Depth= 4.76" Routed to Pond P2 : VEGETATED DETENTION 02 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 801 98 Water Surface (as impervious) 801 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-3.2W: WATER SURFACE (TO VDA) Hydrograph 0.12 1 El Runoff 0.115 0.11 cfs 0.11 Type III 24=hr 0.105 0.1 ,/ 0.095 10- r Rai nfal I=5.00" 0.09 - - - - - - - 0.085 / Runoff Area=801 sf 0.075 Runoff Volume=0.007 of 0.07 0.065 / Runoff Depth=4,76"%.o 3 0.06 _ 0.055 Tc0.0 min 0.045 CN=98 0.04 0.03 0.02 0.015 0.01 0.005 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 50 Summary for Subcatchment PR-4.1: PR-4.1 Runoff = 0.43 cfs @ 12.08 hrs, Volume= 0.035 af, Depth= 4.76" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 37862 98 Roofs H S G C 37862 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.1: PR-4.1 Hydrograph 0.48.4 0.43 cfs ' Runoff 0 6 0.44 0.42 / Type III 24=hr 0.4 / - 0.38 y / 10= r Rainfall=5.00" 0.36 0.34 - / - - - - Runoff Area=3,862 sf 0.32 0.3 Runoff Volume=0.035of 0.28 0.26 Runoff Depth=4,76" 3 0.24 ; 0 0.22 Tc=6.0 min 0.2 0.18 ' CN=98 0.16 0.14 0.12 0.1 0.08 i 0.06 0.04 0.02 0, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 51 Summary for Subcatchment PR-4.2: PR-4.2 Runoff = 0.18 cfs @ 12.08 hrs, Volume= 0.015 af, Depth= 4.76" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 17596 98 Roofs H S G C 17596 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.2: PR-4.2 Hydrograph 0.2 - - - - - - - - - - El Runoff 0.19 0.18 cfs 0.18 Type III 24=hr 0.17 - 0.16 � �� 0.15 10=yr RainfalI=5.00 0.14 / Runoff Area=1,596 sf i 0.13 0.12 Runoff Volume=0.015of 0.11 Runoff Depth=4,76" 3 0.1 0 0.09 Tc=6.0 min 0.08, - - - - CN=98 0.07 r� 0.06 �o 0.05 0.03 0.02 r r, 0.01 r /� /� �, r r it r;fir /�� !�, ter,,,/ // /, r 0, 00/,/,cr'// ,,, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 52 Summary for Subcatchment PR-4.3: PR-4.3 Runoff = 0.18 cfs @ 12.08 hrs, Volume= 0.015 af, Depth= 4.76" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 17602 98 Roofs H S G C 17602 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.3: PR-4.3 Hydrograph 0.2 - - - - - - - - Runoff 0.19 0.18 cfs � 0.18 Type III 24=hr 0.17 0.16 � 10=yr Rainfall=5.00" 0.15 0.14 / Runoff Area=1,602 sf i 0.13 Runoff Volume=0.015 of 0.12 0.11 0.1 Runoff Depth=4,76" 0 3 r 0.09 Tc=6.0 ruin 0.08 r; 0.07 ` CN=98 0.06 r, 0.05 0.03 0.02 r r, 0.01 r 0, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 53 Summary for Subcatchment PR-5.1: PR-5.1 Runoff = 0.78 cfs @ 12.09 hrs, Volume= 0.056 af, Depth= 3.08" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 27966 98 Paved parking HSG C 67512 74 >75% Grass cover, Good HSG C 97478 82 Weighted Average 67512 68.71% Pervious Area 2,966 31.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5.1: PR-5.1 Hydrograph El Runoff 0.85 0.78 cfs 0.8 Type III 24=hr 0.7 j 1 0-yr Rainfall=5.00" 0.65 0.6 ,! Runoff Area=9 478 sf 0.55 Runoff Volume=0.056 of 0.5 0.45 Runoff Depth=3.08" L 04 Tc=6.0 min 0.35 0.3 CN=82 0.25 0.2 0.15 0.1 0.0551 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 54 Summary for Subcatchment PR-5.2: PR-5.2 Runoff = 0.04 cfs @ 12.09 hrs, Volume= 0.003 af, Depth= 2.36" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 561 74 >75% Grass cover, Good HSG C 561 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5.2: PR-5.2 Hydrograph 0.038 0.04 cfs El Runoff 0.036 0.034 % Type III 24=hr 0.032 Ow, 10=yr Rainfall=5.00" 0.03 0.028 Runoff Area=561 sf 0.024 / Runoff Volume=0.003 of 0.022 ,, - - Runoff Depth=2.36" 0.02 0 0.018 Tc=6,0 min 0.016 0.014 CN=74 0.012 0.01 0.006 0.004 0.002 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 55 Summary for Subcatchment PR-6: PR-6 Runoff = 0.43 cfs @ 12.08 hrs, Volume= 0.035 af, Depth= 4.76" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 37793 98 Paved parking HSG C 37793 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-6: PR-6 Hydrograph 0.46 0.43 cfs El Runoff 0.44 0.42 % Type 0.4 III 24=hr 0.38 10=yr Rainfall=5.00" 0.36 Runoff Area-3,793 sf 0.32 0.3 Runoff Volume=0.035of ,.., 0.28 0.26 0.24 Runoff Depth=4,76" 0 0.22 - - - - - - - - - Tc=6.0 min 0.2 0.18 CN=98 0.16 - 0.14 - r; % 0.12 0.1 j 0.08 0.06 0.04 0.02 0, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 56 Summary for Subcatchment PR-7: PR-7 Runoff = 1.38 cfs @ 12.09 hrs, Volume= 0.102 af, Depth= 3.88" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 97281 98 Paved parking HSG C 47447 74 >75% Grass cover, Good, HSG C 137728 90 Weighted Average 4,447 32.39% Pervious Area 9,281 67.61% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-7: PR-7 Hydrograph 1.38 cfs El Runoff Type III 24=hr 10=yr Rainfall=5.00" Runoff Area=13,728 sf 1 Runoff Volume=0.102 of Runoff Depth=3.88" 0 Tc=6.0 min CN=90 0 U,U U U „ U UU U U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 57 Summary for Subcatchment PR-8: PR-8 Runoff = 0.11 cfs @ 12.08 hrs, Volume= 0.009 af, Depth= 4.31" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 864 98 Paved parking HSG C 196 74 >75% Grass cover, Good HSG C 17060 94 Weighted Average 196 18.49% Pervious Area 864 81.51% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-8: PR-8 Hydrograph 0.125 Runoff 0.12 0.11 cfs El 11.0 0 % Type III 24=hr 11 , 0.105, / 0.1 / 1 0myr Rainfall=5.00" 0.095 0.09 Runoff Area=1,060 sf 0.085 0.08 Runoff Volume=0.009 of 0.075 0.07 - - Runoff Depth=4.31 0 0.06 �! Tc=6.0 min 9:0.055 0.05 CN=94 0.045 0.04 0.035 0.03 0.02 0.015 r� 0.01 0.005 %; 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 58 Summary for Subcatchment PR-9: PR-9 Runoff = 0.29 cfs @ 12.08 hrs, Volume= 0.022 af, Depth= 4.20" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 10-yr Rainfall=5.00" Area (sf) CN Description 27202 98 Paved parking HSG C 526 74 >75% Grass cover, Good HSG C 27728 93 Weighted Average 526 19.28% Pervious Area 2,202 80.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-9: PR-9 Hydrograph 0.32 � Runoff 0.29 cfs 0.3 0.28, Type III 24=hr , 0.26 10=yr Rainfall=5.00" 0.24 0.22 Runoff Area=2,728 sf 0.2 Runoff Volume=0.022 of 4 0.18 Runoff-Depth=4.20�� 0.16 o 9: 0.14 min 0.12 CN=93 0.1 0.08 0.06 i 0.04 0.02 O „� ur%, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 59 Summary for Pond 3P: JFPD0406 (Jellyfish) Inflow Area = 0.728 ac, 73.12% Impervious, Inflow Depth = 4.01" for 10-yr event Inflow = 3.17 cfs @ 12.09 hrs, Volume= 0.243 of Outflow = 3.17 cfs @ 12.09 hrs, Volume= 0.243 af, Atten= 0%, Lag= 0.0 min Primary = 0.47 cfs @ 11.63 hrs, Volume= 0.172 of Routed to Link DP-1 : DP-1 (EX-CB) Secondary= 2.70 cfs @ 12.09 hrs, Volume= 0.071 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 153.12'@ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 150.90' JF CSV File Head (feet) 0.00 0.08 0.17 0.25 0.33 0.42 0.50 0.58 0.67 0.75 0.83 0.92 1.00 1.08 1.17 1.25 1.33 1.42 1.50 1.58 1.67 1.75 Disch. (cfs) 0.000 0.003 0.006 0.010 0.013 0.016 0.019 0.049 0.079 0.109 0.139 0.169 0.199 0.229 0.258 0.288 0.318 0.348 0.378 0.408 0.438 0.468 #2 Secondary 152.65' 2.8' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 Primary OutFlow Max=0.47 cfs @ 11.63 hrs HW=152.65' (Free Discharge) L1=JF CSV File (Custom Controls 0.47 cfs) Secondary OutFlow Max=2.70 cfs @ 12.09 hrs HW=153.12' (Free Discharge) L2=Broad-Crested Rectangular Weir(Weir Controls 2.70 cfs @ 2.04 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 60 Pond 3P: JFPD0406 (Jellyfish) Hydrograph 3.17 cfil EM Inflow 3.17 cfs II II llll outflow Primary 10(I X Inflow Area=0.728 ac El secondary Peak Elev=153.12' 3 2.70 cfs 42 2 3 0 u. 00 00 1 cfs gimm 1100 0 U U U U U U U U U U U g U 1111 1111 11111111 11111111 11111111 11111111 1111 11111111 U U U U U U U U U U U U U U U U e U 0 2 4 6 8 10 1214 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 61 Stage-Area-Storage for Pond 3P: JFPD0406 (Jellyfish) Elevation Storage Elevation Storage Elevation Storage (feet) (acre-feet) (feet) (acre-feet) (feet) (acre-feet) 150.90 0.000 151.92 0.000 152.94 0.000 150.92 0.000 151.94 0.000 152.96 0.000 150.94 0.000 151.96 0.000 152.98 0.000 150.96 0.000 151.98 0.000 153.00 0.000 150.98 0.000 152.00 0.000 153.02 0.000 151.00 0.000 152.02 0.000 153.04 0.000 151.02 0.000 152.04 0.000 153.06 0.000 151.04 0.000 152.06 0.000 153.08 0.000 151.06 0.000 152.08 0.000 153.10 0.000 151.08 0.000 152.10 0.000 153.12 0.000 151.10 0.000 152.12 0.000 151.12 0.000 152.14 0.000 151.14 0.000 152.16 0.000 151.16 0.000 152.18 0.000 151.18 0.000 152.20 0.000 151.20 0.000 152.22 0.000 151.22 0.000 152.24 0.000 151.24 0.000 152.26 0.000 151.26 0.000 152.28 0.000 151.28 0.000 152.30 0.000 151.30 0.000 152.32 0.000 151.32 0.000 152.34 0.000 151.34 0.000 152.36 0.000 151.36 0.000 152.38 0.000 151.38 0.000 152.40 0.000 151.40 0.000 152.42 0.000 151.42 0.000 152.44 0.000 151.44 0.000 152.46 0.000 151.46 0.000 152.48 0.000 151.48 0.000 152.50 0.000 151.50 0.000 152.52 0.000 151.52 0.000 152.54 0.000 151.54 0.000 152.56 0.000 151.56 0.000 152.58 0.000 151.58 0.000 152.60 0.000 151.60 0.000 152.62 0.000 151.62 0.000 152.64 0.000 151.64 0.000 152.66 0.000 151.66 0.000 152.68 0.000 151.68 0.000 152.70 0.000 151.70 0.000 152.72 0.000 151.72 0.000 152.74 0.000 151.74 0.000 152.76 0.000 151.76 0.000 152.78 0.000 151.78 0.000 152.80 0.000 151.80 0.000 152.82 0.000 151.82 0.000 152.84 0.000 151.84 0.000 152.86 0.000 151.86 0.000 152.88 0.000 151.88 0.000 152.90 0.000 151.90 0.000 152.92 0.000 POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11l 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 62 Summary for Pond P2: VEGETATED DETENTION 02 Inflow Area = 0.989 ac, 19.40% Impervious, Inflow Depth = 1.62" for 10-yr event Inflow = 0.96 cfs @ 12.42 hrs, Volume= 0.133 of Outflow = 0.96 cfs @ 12.43 hrs, Volume= 0.133 af, Atten= 0%, Lag= 0.4 min Discarded = 0.00 cfs @ 12.43 hrs, Volume= 0.003 of Primary = 0.96 cfs @ 12.43 hrs, Volume= 0.131 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 154.18'@ 12.43 hrs Surf.Area= 193 sf Storage= 72 cf Plug-Flow detention time= 11.7 min calculated for 0.133 of(100% of inflow) Center-of-Mass det. time= 11.8 min ( 855.2 - 843.4 ) Volume Invert Avail.Storage Storage Description #1 153.60' 316 cf Custom Stage Data (Irregular)Listed below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 153.60 56 40.0 0 0 56 154.00 156 56.0 41 41 180 155.00 416 117.0 276 316 15024 Device Routing Invert Outlet Devices #1 Device 2 154.00' 15.0" Horiz. 15" GRATE C= 0.600 Limited to weir flow at low heads #2 Primary 152.10' 12.0" Round 12" HDPE L= 21.7' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 152.10'/ 151.10' S= 0.0461 T Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.79 sf #3 Discarded 153.60' 0.270 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.43 hrs HW=154.18' (Free Discharge) L3=Exfi1tration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=0.96 cfs @ 12.43 hrs HW=154.18' (Free Discharge) L2=12" HDPE (Passes 0.96 cfs of 3.75 cfs potential flow) L1=15" GRATE (Weir Controls 0.96 cfs @ 1.38 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 63 Pond P2: VEGETATED DETENTION 02 Hydrograph 0.96 cfs Inflow 0.96 cfs `� I uuullll Outflow Infl w �r Discarded 0.96 cfs o ea=0.989 ac Primary 1 Peak Elev=154.18' Storage=72 cf 0 0 0 P, ` r /// r I F �iiii ;:;iii I 1 1; lill ii i: r ................. r O/,/ �VOW�;/� 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 64 Stage-Area-Storage for Pond P2: VEGETATED DETENTION 02 Elevation Surface Storage Elevation Surface Storage (feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet) 153.60 56 0 154.62 302 180 153.62 60 1 154.64 308 186 153.64 64 2 154.66 314 193 153.66 68 4 154.68 319 199 153.68 72 5 154.70 325 205 153.70 76 7 154.72 331 212 153.72 81 8 154.74 336 219 153.74 85 10 154.76 342 225 153.76 90 12 154.78 348 232 153.78 95 13 154.80 354 239 153.80 100 15 154.82 360 247 153.82 105 17 154.84 366 254 153.84 110 20 154.86 372 261 153.86 115 22 154.88 378 269 153.88 121 24 154.90 384 276 153.90 126 27 154.92 391 284 153.92 132 29 154.94 397 292 153.94 138 32 154.96 403 300 153.96 144 35 154.98 410 308 153.98 150 38 155.00 416 316 154.00 156 41 154.02 160 44 154.04 164 47 154.06 168 50 154.08 172 54 154.10 176 57 154.12 181 61 154.14 185 65 154.16 189 68 154.18 194 72 154.20 198 76 154.22 202 80 154.24 207 84 154.26 212 88 154.28 216 93 154.30 221 97 154.32 226 101 154.34 230 106 154.36 235 111 154.38 240 115 154.40 245 120 154.42 250 125 154.44 255 130 154.46 260 135 154.48 265 141 154.50 270 146 154.52 276 151 154.54 281 157 154.56 286 163 154.58 292 168 154.60 297 174 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 65 Summary for Pond P3: VEGETATED DETENTION 01 Inflow Area = 0.258 ac, 42.47% Impervious, Inflow Depth = 3.41" for 10-yr event Inflow = 0.96 cfs @ 12.08 hrs, Volume= 0.073 of Outflow = 0.94 cfs @ 12.10 hrs, Volume= 0.073 af, Atten= 2%, Lag= 1.0 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.007 of Primary = 0.94 cfs @ 12.10 hrs, Volume= 0.066 of Routed to Pond 3P : J FPD0406 (Jellyfish) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 154.45'@ 12.10 hrs Surf.Area= 423 sf Storage= 249 cf Plug-Flow detention time=92.6 min calculated for 0.073 of(100% of inflow) Center-of-Mass det. time= 92.9 min ( 894.3 - 801.4 ) Volume Invert Avail.Storage Storage Description #1 153.60' 540 cf VEGETATED DETENTION 01 (Irregullar�isted below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 153.60 195 58.0 0 0 195 154.00 272 65.0 93 93 268 155.00 650 162.0 447 540 25024 Device Routing Invert Outlet Devices #1 Device 2 154.25' 12.0" Horiz. 12" AD (Orifice/Grate) C= 0.600 Limited to weir flow at low heads #2 Primary 152.00' 10.0" Round 10" HDPE L= 48.1' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 152.00'/ 151.51' S= 0.0102 7' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #3 Discarded 153.60' 0.270 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=154.45' (Free Discharge) L3=Exfi1tration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=0.94 cfs @ 12.10 hrs HW=154.45' (Free Discharge) L2=10" HDPE (Passes 0.94 cfs of 2.96 cfs potential flow) L1=12" AD (Orifice/Grate)(Weir Controls 0.94 cfs @ 1.47 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 10-yr Rainfall=5.00IVY Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 66 Pond P3: VEGETATED DETENTION 01 Hydrograph --------------------------------------------------------- 0.96 cfs EM Inflow outflow 0.94 cfs I°°ullll 01 Discarded �0 Inflow Area=0.258 ac 0 Primary 0.94 cfs Peak Elev=154.45' Storage=249f c _O LL i cfs 0 IPIIFIIIPIIF]PIPPIPIF]PIPPIPIF 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 67 Stage-Area-Storage for Pond P3: VEGETATED DETENTION 01 Elevation Surface Storage Elevation Surface Storage (feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet) 153.60 195 0 154.62 487 325 153.62 199 4 154.64 495 335 153.64 202 8 154.66 503 345 153.66 206 12 154.68 511 355 153.68 209 16 154.70 520 365 153.70 213 20 154.72 528 376 153.72 217 25 154.74 536 387 153.74 220 29 154.76 544 397 153.76 224 34 154.78 553 408 153.78 228 38 154.80 561 419 153.80 232 43 154.82 570 431 153.82 236 47 154.84 579 442 153.84 240 52 154.86 587 454 153.86 244 57 154.88 596 466 153.88 248 62 154.90 605 478 153.90 252 67 154.92 614 490 153.92 256 72 154.94 623 502 153.94 260 77 154.96 632 515 153.96 264 82 154.98 641 528 153.98 268 88 155.00 650 540 154.00 272 93 154.02 278 98 154.04 284 104 154.06 290 110 154.08 296 116 154.10 303 122 154.12 309 128 154.14 315 134 154.16 322 140 154.18 328 147 154.20 335 154 154.22 341 160 154.24 348 167 154.26 355 174 154.28 362 181 154.30 368 189 154.32 375 196 154.34 382 204 154.36 389 211 154.38 397 219 154.40 404 227 154.42 411 235 154.44 418 244 154.46 426 252 154.48 433 261 154.50 441 269 154.52 448 278 154.54 456 287 154.56 464 297 154.58 471 306 154.60 479 315 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 11l 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 68 Summary for Pond SB1: P1 - STORMWATER BASIN Inflow Area = 0.841 ac, 9.22% Impervious, Inflow Depth = 2.48" for 10-yr event Inflow = 2.03 cfs @ 12.12 hrs, Volume= 0.174 of Outflow = 0.80 cfs @ 12.44 hrs, Volume= 0.174 af, Atten= 61%, Lag= 18.9 min Discarded = 0.02 cfs @ 12.44 hrs, Volume= 0.092 of Primary = 0.78 cfs @ 12.44 hrs, Volume= 0.082 of Routed to Pond P2 : VEGETATED DETENTION 02 Secondary= 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 157.59'@ 12.44 hrs Surf.Area= 3,408 sf Storage= 3,139 cf Plug-Flow detention time=755.1 min calculated for 0.174 of(100% of inflow) Center-of-Mass det. time= 755.4 min ( 1,582.2 - 826.8 ) Volume Invert Avail.Storage Storage Description #1 156.50' 7,085 cf Basin (Irregular)Listed below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 156.50 21369 226.0 0 0 25369 157.00 21834 239.0 15299 15299 25864 158.00 33838 264.0 35323 45622 35896 158.60 43378 276.0 25463 75085 45436 Device Routing Invert Outlet Devices #1 Discarded 156.50' 0.270 in/hr Infiltration over Surface area #2 Primary 157.50' 12.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 #3 Device 4 157.60' 1.0" x 9.0" Horiz. 12" Orifice/Grate X 8.00 C= 0.600 in 12.0" Grate (64% open area) Limited to weir flow at low heads #4 Secondary 153.00' 12.0" Round 12" HDPE L= 50.4' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 153.00'/ 152.00' S= 0.0198 7' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 69 Discarded OutFlow Max=0.02 cfs @ 12.44 hrs HW=157.59' (Free Discharge) L1=Infiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.78 cfs @ 12.44 hrs HW=157.59' (Free Discharge) L2=Broad-Crested Rectangular Weir(Weir Controls 0.78 cfs @ 0.72 fps) Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=156.50' (Free Discharge) L4=12" HDPE (Passes 0.00 cfs of 5.17 cfs potential flow) L3=12" Orifice/Grate ( Controls 0.00 cfs) Pond SB1: P1 - STORMWATER BASIN Hydrograph --------------------------------------------------------- 2.03 cfs EM Inflow llll Outflow Inflow Area=0.841 ac Discarded Primar y Secondary Peak Elev=157.59' 0 2 Storage=3,139 cf 0.80 cfs 3 0.78 cfs � 1 mm mmm cfs 'r 0.00 cfs 0 0 2 4 6 8 1012 1416 1820 2224 2628 3032 34 36384042 44464850 5254 5658 6062 6466 6870 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 70 Stage-Area-Storage for Pond SB1: P1 - STORMWATER BASIN Elevation Surface Storage (feet) (sq-ft) (cubic-feet) 156.50 23369 0 156.55 23414 120 156.60 23459 241 156.65 23504 365 156.70 23550 492 156.75 2596 620 156.80 2)643 751 156.85 25690 885 156.90 23738 1,020 156.95 23786 11159 157.00 23834 1,299 157.05 23881 1,442 157.10 23928 1587 157.15 23975 1,735 157.20 3,023 11885 157.25 3,071 2,037 157.30 33119 2,192 157.35 33168 2,349 157.40 33217 21508 157.45 33267 2,671 157.50 33317 2,835 157.55 33367 3,002 157.60 33418 3,172 157.65 3,469 31344 157.70 3521 3519 157.75 33573 3,696 157.80 33625 3,876 157.85 33678 41059 157.90 33731 4,244 157.95 33784 4,432 158.00 33838 4,622 158.05 33882 4,815 158.10 3,926 51011 158.15 3,970 5,208 158.20 43014 5,407 158.25 43059 5,609 158.30 43104 51813 158.35 43149 6,020 158.40 43194 6,228 158.45 43240 6,439 158.50 43286 6,652 158.55 4,332 61868 158.60 41378 77085 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 71 Summary for Link DP-1: DP-1 (EX-CB) Inflow Area = 3.490 ac, 50.18% Impervious, Inflow Depth = 3.15" for 10-yr event Inflow = 11.24 cfs @ 12.09 hrs, Volume= 0.917 of Primary = 11.24 cfs @ 12.09 hrs, Volume= 0.917 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-1: DP-1 (EX-CB) Hydrograph Inflow ,� E Primary 12 1.24 cfs Inflow Area=3.490 ac 10 9 ,212 7 3 6 % o 5 4 3 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 10-yr Rainfall=5.00" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 72 Summary for Link DP-2: DP-2 (OFF-SITE AIRFIELD) Inflow Area = 0.218 ac, 31.29% Impervious, Inflow Depth = 3.08" for 10-yr event Inflow = 0.78 cfs @ 12.09 hrs, Volume= 0.056 of Primary = 0.78 cfs @ 12.09 hrs, Volume= 0.056 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-2: DP-2 (OFF-SITE AIRFIELD) Hydrograph Inflow El Primary 0.85 0.78 cfs 0.8 Inflow Area=0.218 ac 0.75 0.7 0.65 0.6 0.55 0.45 3 LL - 0.35 0.3 j 0.25 0.15 0.1 r, 0.05 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 73 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentPR-1: PR-1 Runoff Area=10,160 sf 36.37% Impervious Runoff Depth=4.34" Tc=6.0 min CN=84 Runoff=1.17 cfs 0.084 of SubcatchmentPR-10: PR-10 Runoff Area=34,216 sf 61.92% Impervious Runoff Depth=4.88" Tc=6.0 min CN=89 Runoff=4.31 cfs 0.319 of SubcatchmentPR-11: PR-11 Runoff Area=23,923 sf 40.23% Impervious Runoff Depth=4.34" Tc=6.0 min CN=84 Runoff=2.75 cfs 0.198 of SubcatchmentPR-1W:WATERSURFACE Runoff Area=1,077 sf 100.00% Impervious Runoff Depth=5.91" Tc=0.0 min CN=98 Runoff=0.18 cfs 0.012 of SubcatchmentPR-2: PR-2 Runoff Area=10,646 sf 85.97% Impervious Runoff Depth=5.56" Tc=6.0 min CN=95 Runoff=1.45 cfs 0.113 of SubcatchmentPR-3.1: PR-3.1 Runoff Area=33,659 sf 1.17% Impervious Runoff Depth=3.21" Flow Length=279' Tc=8.6 min CN=73 Runoff=2.66 cfs 0.207 of SubcatchmentPR-3.1W: PR-3.1 Runoff Area=2,985 sf 100.00% Impervious Runoff Depth=5.91" Tc=0.0 min CN=98 Runoff=0.50 cfs 0.034 of SubcatchmentPR-3.2: PR-3.2 Runoff Area=5,636 sf 74.13% Impervious Runoff Depth=5.22" Tc=6.0 min C N=92 Runoff=0.74 cfs 0.056 of SubcatchmentPR-3.2W:WATERSURFACE Runoff Area=801 sf 100.00% Impervious Runoff Depth=5.91" Tc=0.0 min CN=98 Runoff=0.14 cfs 0.009 of SubcatchmentPR-4.1: PR-4.1 Runoff Area=3,862 sf 100.00% Impervious Runoff Depth=5.91" Tc=6.0 min CN=98 Runoff=0.53 cfs 0.044 of SubcatchmentPR-4.2: PR-4.2 Runoff Area=1,596 sf 100.00% Impervious Runoff Depth=5.91" Tc=6.0 min CN=98 Runoff=0.22 cfs 0.018 of SubcatchmentPR-4.3: PR-4.3 Runoff Area=1,602 sf 100.00% Impervious Runoff Depth=5.91" Tc=6.0 min CN=98 Runoff=0.22 cfs 0.018 of SubcatchmentPR-5.1: PR-5.1 Runoff Area=9,478 sf 31.29% Impervious Runoff Depth=4.13" Tc=6.0 min CN=82 Runoff=1.04 cfs 0.075 of SubcatchmentPR-5.2: PR-5.2 Runoff Area=561 sf 0.00% Impervious Runoff Depth=3.31" Tc=6.0 min CN=74 Runoff=0.05 cfs 0.004 of SubcatchmentPR-6: PR-6 Runoff Area=3,793 sf 100.00% Impervious Runoff Depth=5.91" Tc=6.0 min CN=98 Runoff=0.52 cfs 0.043 of SubcatchmentPR-7: PR-7 Runoff Area=13,728 sf 67.61% Impervious Runoff Depth=4.99" Tc=6.0 min CN=90 Runoff=1.76 cfs 0.131 of POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 74 SubcatchmentPR-8: PR-8 Runoff Area=1,060 sf 81.51% Impervious Runoff Depth=5.45" Tc=6.0 min CN=94 Runoff=0.14 cfs 0.011 of SubcatchmentPR-9: PR-9 Runoff Area=2,728 sf 80.72% Impervious Runoff Depth=5.33" Tc=6.0 min CN=93 Runoff=0.36 cfs 0.028 of Pond 3P: JFPD0406(Jellyfish) Peak Elev=153.21' Inflow=4.00 cfs 0.310 of Primary=0.47 cfs 0.210 of Secondary=3.53 cfs 0.100 of Outflow=4.00 cfs 0.310 of Pond P2: VEGETATED DETENTION 02 Peak Bev=154.32' Storage=101 cf Inflow=2.29 cfs 0.210 of Discarded=0.00 cfs 0.003 of Primary=2.29 cfs 0.207 of Outflow=2.29 cfs 0.210 of Pond P3: VEGETATED DETENTION 01 Peak Elev=154.49' Storage=267 cf Inflow=1.26 cfs 0.096 of Discarded=0.00 cfs 0.008 of Primary=1.23 cfs 0.089 of Outflow=1.24 cfs 0.096 of Pond SB1: P1 -STORMWATERBASIN Peak Elev=157.66' Storage=3,386 cf Inflow=2.85 cfs 0.241 of Discarded=0.02 cfs 0.093 of Primary=1.87 cfs 0.145 of Secondary=0.16 cfs 0.003 of Outflow=2.05 cfs 0.241 of Link DP-1: DP-1 (EX-CB) Inflow=14.34 cfs 1.226 of Primary=14.34 cfs 1.226 of Link DP-2: DP-2(OFF-SITE AIRFIELD) Inflow=1.04 cfs 0.075 of Primary=1.04 cfs 0.075 of Total Runoff Area = 3.708 ac Runoff Volume = 1.405 of Average Runoff Depth = 4.55" 50.93% Pervious = 1.888 ac 49.07% Impervious = 1.819 ac POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 75 Summary for Subcatchment PR-1: PR-1 Runoff = 1.17 cfs @ 12.09 hrs, Volume= 0.084 af, Depth= 4.34" Routed to Pond P3 : VEGETATED DETENTION 01 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 37695 98 Paved parking HSG C 57539 74 >75% Grass cover, Good HSG C 926 89 Gravel roads, HSG C 107160 84 Weighted Average 6,465 63.63% Pervious Area 31695 36.37% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-1: PR-1 Hydrograph 1.17 cfs El Runoff f Type III 24=hr 1 j 25=yr Rainfall=6.15" Runoff Area=10,160 sf Runoff Volume=0.084 of Runoff Depth=4.34" 0 Tc=6.0 min CN=84 i 0 U UU U U U U 10��IFIFIFITII u 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 76 Summary for Subcatchment PR-10: PR-10 Runoff = 4.31 cfs @ 12.08 hrs, Volume= 0.319 af, Depth= 4.88" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 47033 74 >75% Grass cover, Good, HSG C 695 98 Roofs HSG C 201490 98 Paved parking HSG C 8,998 74 >75% Grass cover, Good HSG C 347216 89 Weighted Average 131031 38.08% Pervious Area 217185 61.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-10: PR-10 Hydrograph 4.31 cfs El Runoff Type III 24 hr 4 /% 25=yr Rainfall=6.15" Runoff Area=34,216 sf 3 Runoff Volume=0.319 of j Runoff Depth=4.88" 3 o % Tc=6.0 min / CN=89 ,j 0 „/�/fa,/�"aril;,,"',,,i;,'% i'a'„ "�a ,u,;,�%/,,,r/;,' o, "a!�'�o„/ �a,/�"ui,�i,,, /,,,,i„�"'„r/„r�;,;o'-. 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 77 Summary for Subcatchment PR-11: PR-11 Runoff = 2.75 cfs @ 12.09 hrs, Volume= 0.198 af, Depth= 4.34" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 474 70 Woods, Good HSG C 17340 74 >75% Grass cover, Good, HSG C 8,880 98 Paved parking HSG C 744 98 Roofs HSG C 127485 74 >75% Grass cover, Good HSG C 23,923 84 Weighted Average 141299 59.77% Pervious Area 9,624 40.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-11: PR-11 Hydrograph 3 2.75 cfs El Runoff Type III 24=hr 25=yr Rainfall=6.15" Runoff Area=23,923 sf Runoff Volume=0.198 of Runoff Depth=4.34" o % Tc=6.0 min � CN=84 0 U U UU U U,U;U U U U U Vllqll�IIFIIPIIFIIF]�IIFIIFIIFIIF]11111 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 78 Summary for Subcatchment PR-1W: WATER SURFACE (TO VDA) Runoff = 0.18 cfs @ 12.00 hrs, Volume= 0.012 af, Depth= 5.91" Routed to Pond P3 : VEGETATED DETENTION 01 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 17077 98 Water Surface (as impervious) 17077 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-1 W: WATER SURFACE (TO VDA) Hydrograph 0.2 El Runoff 0.19 0.18 cfs 0.18 % Type III 24=hr 0.17 25 r Rainfall=6.15" 0.15 - 0.14 - Runoff Area=11,077 sf 0.13 / Runoff Volume=0.012 of 0.12 011 / Runoff Depth=5,91 0.1 ° 0.09 Tc=0.0 min 0.0s 0.07 CN=98 0.06 0.04 0.03 � 0.02 0.01 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 79 Summary for Subcatchment PR-2: PR-2 Runoff = 1.45 cfs @ 12.08 hrs, Volume= 0.113 af, Depth= 5.56" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 97152 98 Paved parking HSG C 17494 74 >75% Grass cover, Good HSG C 107646 95 Weighted Average 1,494 14.03% Pervious Area 9,152 85.97% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-2: PR-2 Hydrograph 1.45 cfs El Runoff Type III 24=hr 0/1 25myr Rainfall=6.15" M, Runoff Area=10,646 sf Runoff Volume=0.113 f a MR, Runoff Depth=5.56" C Tc=6.0 min, CN=95 /r i O %,'„ 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 80 Summary for Subcatchment PR-3.1: PR-3.1 Runoff = 2.66 cfs @ 12.12 hrs, Volume= 0.207 af, Depth= 3.21" Routed to Pond S131 : P1 - STORMWATER BASIN Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 131226 70 Woods, Good HSG C 1,199 89 Gravel roads, HSG C 167 98 Concrete (wall/pads) 191 98 Roofs HSG C 35 98 Paved walk 181841 74 >75% Grass cover, Good, HSG C 331659 73 Weighted Average 331266 98.83% Pervious Area 393 1.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.9 33 0.0730 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.74" 2.0 17 0.0250 0.14 Sheet Flow, Grass: Short n= 0.150 P2= 3.74" 1.7 229 0.0200 2.28 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 8.6 279 Total POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 81 Subcatchment PR-3.1: PR-3.1 Hydrograph 2. 66 cfS El Runoff Type III 24=hr W 25=yr Rainfall=6.15" Runoff Area=33,659 sf 2 � Runoff Volume=0.207 of Runoff Depth=3.21 FlowLength=279' o ,., Tc=8.6 min - CN=73 //, /, /, /' r r / r/ / //=/ /5 Ruiuimu�� .&0111z,/ I 0 U U U U U U U U U U U U U U U U U U 1111 1111 11111111 1111 111 IFFFIF]I�IFV�U U U U U U U U U U U U U U I U U U U U U 1111 11111111 1111 1111 1111 1111 1111 1111 1111 11111111 U U U U U U U U U U U U U UU U U U U U U U U UU U U 1111 '111 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 441 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 82 Summary for Subcatchment PR-3.1 W: PR-3.1 Runoff = 0.50 cfs @ 12.00 hrs, Volume= 0.034 af, Depth= 5.91" Routed to Pond S131 : P1 - STORMWATER BASIN Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 27985 98 Water Surface (as Impervious) 27985 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-3.1 W: PR-3.1 Hydrograph 0.55 0.50 cfs El Runoff 0.5 ' Type III 24=hr 0.45 y 25= r Rainfall=6.15" � 0.4 Runoff Area=2,985 sf 0.35 Runoff Volume=0.034 of 0.3 Runoff Depth=5,91 0 3 : 0.25 Tc=0.0 min CN=98 0.15 0.1 0.05 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 83 Summary for Subcatchment PR-3.2: PR-3.2 Runoff = 0.74 cfs @ 12.08 hrs, Volume= 0.056 af, Depth= 5.22" Routed to Pond P2 : VEGETATED DETENTION 02 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 47178 98 Paved parking HSG C 17458 74 >75% Grass cover, Good HSG C 57636 92 Weighted Average 17458 25.87% Pervious Area 4,178 74.13% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3.2: PR-3.2 Hydrograph 0.8 0.74 cfs El Runoff 0.75 0.7 Type III 24 hr , 0.65 25=yr Rainfall=6.15" 0.6 Runoff Area=5,636 sf 0.55 0.5 Runoff Volume=0.056 of 0.45 Runoff Depth=5,22" c 0.4 ,% ■ 0.35 Tc=6.0 min �, CN=92 0.25 0.2 % 0.15 i i 0.1 i 0.05 ,;' , zo a'„-it„„, , , i, �,;, ,,,,,,l;,,, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 84 Summary for Subcatchment PR-3.2W: WATER SURFACE (TO VDA) Runoff = 0.14 cfs @ 12.00 hrs, Volume= 0.009 af, Depth= 5.91" Routed to Pond P2 : VEGETATED DETENTION 02 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 801 98 Water Surface (as impervious) 801 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-3.2W: WATER SURFACE (TO VDA) Hydrograph 0.15 0.14 cfs El Runoff 0.14 0.13 Type III 24=hr � 0.1225=yr% Rainfall=6.15" 0.11 Runoff Area=801 sf 0.1 0.09 Runoff Volume=0.009 of 0.08 Runoff Depth=5,91 3 0 0.07 Tc=0.0min 0.06 CN=98 0.05 ''�' j r, 0.03 — 0.02 '! 0.01 0 Ua 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 85 Summary for Subcatchment PR-4.1: PR-4.1 Runoff = 0.53 cfs @ 12.08 hrs, Volume= 0.044 af, Depth= 5.91" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 37862 98 Roofs H S G C 37862 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.1: PR-4.1 Hydrograph 0.53 cfs El Runoff 0.55 Type III 24=hr 05 25=yr Rainfall=6.15" 0.45 Runoff Area=3,862 sf 0.4 Runoff Volume=0.044 of 0.35 0.3 Runoff Depth=5,91 3 ��% o Tc=6.0 0.25 m i n � ,,, 0.2 CN=98 0.15 0.1 0.05 01 U U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 86 Summary for Subcatchment PR-4.2: PR-4.2 Runoff = 0.22 cfs @ 12.08 hrs, Volume= 0.018 af, Depth= 5.91" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 17596 98 Roofs H S G C 17596 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.2: PR-4.2 Hydrograph 0.24 0.22 cfs El Runoff 0.23 0.22 Type III 24=hr 0.21 25-yr Rainfall=6.150.19 0.18 0.17 Runoff Area 1,596 sf 0.16 Runoff Volume=0.018of 0.15 0.14 , 0.13 Runoff Depth=5,91 3 0.12 ,0 0.11 Tc=6.0 min 0.11, 0.09 CN=98 0.08 0.07 0.06 i 0.04 i 0.03 0.02 0.01 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 4850 52 54 56 58 60 62 64 66 68 7072 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 87 Summary for Subcatchment PR-4.3: PR-4.3 Runoff = 0.22 cfs @ 12.08 hrs, Volume= 0.018 af, Depth= 5.91" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 17602 98 Roofs H S G C 17602 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.3: PR-4.3 Hydrograph 0.24 0.22 cfs El Runoff 0.23 0.22 Type III 24=hr 0.21 0.2 - - - - - - 25=yr Rainfall=6.15��0.1 - - - - - 0.18 - - - - - - - Runoff Area-1,602 sf 0.17 �! 0.16 0.15 Runoff Volume=0.018of .. ........ 4 0.14 , 0.13 Runoff Depth=5,91 - 3 0.12 0.11 Tc=6.0 min 0.11,11, 0.097 CN=98 0.08 0.07 0.05 0.04 i 0.03 0.02 0.01 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 88 Summary for Subcatchment PR-5.1: PR-5.1 Runoff = 1.04 cfs @ 12.09 hrs, Volume= 0.075 af, Depth= 4.13" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 27966 98 Paved parking HSG C 67512 74 >75% Grass cover, Good HSG C 97478 82 Weighted Average 67512 68.71% Pervious Area 2,966 31.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5.1: PR-5.1 Hydrograph 1.04 cfs El Runoff % Type III 24=hr j 25=yr Rainfall=6.15" Runoff Area=9,478 sf j Runoff Volume=0.075 of Runoff Depth=4.13" 0 Tc=6.0 min CN=82 0 U'U'U'llu U UU U U U U u u U U U U U U U U U U U U U U U U U U U U 1111 1111 1111 U U U U U U U U U U U U U U U U U U U U U U U U U U U U1UU U U 1111 1111 1111 1111 1111 11 111111111 U U U U U U U U U u U U UU19 U U U U U U U UU U U U U U 1111 1111 1111 1111 1111 11111111 1111 U U U U U U UU U U U U U Ulu U U U U U U UU U U U U U U U U U U 1111 1111 1111 11111111 1111 1111 1111 U U U U U UU U U U U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 89 Summary for Subcatchment PR-5.2: PR-5.2 Runoff = 0.05 cfs @ 12.09 hrs, Volume= 0.004 af, Depth= 3.31" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 561 74 >75% Grass cover, Good HSG C 561 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5.2: PR-5.2 Hydrograph 0.055 0.05 cfs El Runoff 0.05 �' Type III 24=hr 0.045 25=yr Rainfall=6.15" Runoff Area=561 sf 0.035 Runoff Volume=0.004 of .� - 0.03 Runoff Depth=3.31 0 Tc=6.0 min 0.02 '% CN=74 0.015 0.01 i 0.005 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 90 Summary for Subcatchment PR-6: PR-6 Runoff = 0.52 cfs @ 12.08 hrs, Volume= 0.043 af, Depth= 5.91" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 37793 98 Paved parking HSG C 37793 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-6: PR-6 Hydrograph 0.55 0.52 cfs 0 Runoff 0.5 Type III 24=hr % 25=yr Rainfall=6.15" Runoff Area-3 793 sf 0.4 Runoff Volume=0.043of o 0.3 Runoff Depth=5,91 0 0.25 Tc=6.0min 0.2 CN=98 0.15 0.1 i 0.05 op Ir 0 e, 0 2 4 6 8 10 12 14 16 1820 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 91 Summary for Subcatchment PR-7: PR-7 Runoff = 1.76 cfs @ 12.08 hrs, Volume= 0.131 af, Depth= 4.99" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 97281 98 Paved parking HSG C 47447 74 >75% Grass cover, Good, HSG C 137728 90 Weighted Average 4,447 32.39% Pervious Area 9,281 67.61% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-7: PR-7 Hydrograph 1.76 cfs El Runoff Type III 24=hr 25=yr Rainfall=6.15" j Runoff Area=13,728 sf Runoff Volume=0.131 of 1 Runoff Depth=4.99" 0 Tc=6.0 min , , CN=90 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 92 Summary for Subcatchment PR-8: PR-8 Runoff = 0.14 cfs @ 12.08 hrs, Volume= 0.011 af, Depth= 5.45" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 864 98 Paved parking HSG C 196 74 >75% Grass cover, Good HSG C 17060 94 Weighted Average 196 18.49% Pervious Area 864 81.51% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-8: PR-8 Hydrograph 0.15 0.14 cfs El Runoff 0.14 Type III 24=hr 0.13 25=yr Rainfall=6.15" 0.12 0.11 Runoff Area=1,060 sf 0.1 Runoff Volume=0.01 1 of 0.09 0.08 Runoff Depth=5,45" 3 — 0.07 0 Tc=6.0 min 0.06 ' CN=94 � r 0.05 ' 0.04 0.02 0.01ImxAn' 0 „ 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 93 Summary for Subcatchment PR-9: PR-9 Runoff = 0.36 cfs @ 12.08 hrs, Volume= 0.028 af, Depth= 5.33" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 25-yr Rainfall=6.15" Area (sf) CN Description 27202 98 Paved parking HSG C 526 74 >75% Grass cover, Good HSG C 27728 93 Weighted Average 526 19.28% Pervious Area 2,202 80.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-9: PR-9 Hydrograph 0.4 Runoff o.3s 0.36 cfs El 0.36 % Type III 24=hr 03. 4 0.32 25=yr Rainfall=6.15" 0.3 Runoff Area-2 728 sf 0.2s - 0.26 % .-. 0.24 Runoff Volume=0.028 of 0.22 % Runoff Depth=5,33" 3 0.2 ' ° 0.18 Tc=6.0 min 0.16,111, - - - - - - - CN=93 0.14 0.12 i 0.1 0.08 0.06 - - 0.04 0.02 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 94 Summary for Pond 3P: JFPD0406 (Jellyfish) Inflow Area = 0.728 ac, 73.12% Impervious, Inflow Depth = 5.12" for 25-yr event Inflow = 4.00 cfs @ 12.09 hrs, Volume= 0.310 of Outflow = 4.00 cfs @ 12.09 hrs, Volume= 0.310 af, Atten= 0%, Lag= 0.0 min Primary = 0.47 cfs @ 11.57 hrs, Volume= 0.210 of Routed to Link DP-1 : DP-1 (EX-CB) Secondary= 3.53 cfs @ 12.09 hrs, Volume= 0.100 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 153.21'@ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 150.90' JF CSV File Head (feet) 0.00 0.08 0.17 0.25 0.33 0.42 0.50 0.58 0.67 0.75 0.83 0.92 1.00 1.08 1.17 1.25 1.33 1.42 1.50 1.58 1.67 1.75 Disch. (cfs) 0.000 0.003 0.006 0.010 0.013 0.016 0.019 0.049 0.079 0.109 0.139 0.169 0.199 0.229 0.258 0.288 0.318 0.348 0.378 0.408 0.438 0.468 #2 Secondary 152.65' 2.8' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 Primary OutFlow Max=0.47 cfs @ 11.57 hrs HW=152.65' (Free Discharge) L1=JF CSV File (Custom Controls 0.47 cfs) Secondary OutFlow Max=3.53 cfs @ 12.09 hrs HW=153.21' (Free Discharge) L2=Broad-Crested Rectangular Weir(Weir Controls 3.53 cfs @ 2.27 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 95 Pond 3P: JFPD0406 (Jellyfish) Hydrograph 4.00 cfs EM Inflow 4.00 cfs IIII llll outflow Hrimary Inflow Area=0.728 ac El Secondary 4(1 Peak Elev=153.21' 3.53 cfs G 3 o 2 u. - I cfs 0 2 4 6 8 10 1214 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 96 Stage-Area-Storage for Pond 3P: JFPD0406 (Jellyfish) Elevation Storage Elevation Storage Elevation Storage (feet) (acre-feet) (feet) (acre-feet) (feet) (acre-feet) 150.90 0.000 151.92 0.000 152.94 0.000 150.92 0.000 151.94 0.000 152.96 0.000 150.94 0.000 151.96 0.000 152.98 0.000 150.96 0.000 151.98 0.000 153.00 0.000 150.98 0.000 152.00 0.000 153.02 0.000 151.00 0.000 152.02 0.000 153.04 0.000 151.02 0.000 152.04 0.000 153.06 0.000 151.04 0.000 152.06 0.000 153.08 0.000 151.06 0.000 152.08 0.000 153.10 0.000 151.08 0.000 152.10 0.000 153.12 0.000 151.10 0.000 152.12 0.000 153.14 0.000 151.12 0.000 152.14 0.000 153.16 0.000 151.14 0.000 152.16 0.000 153.18 0.000 151.16 0.000 152.18 0.000 153.20 0.000 151.18 0.000 152.20 0.000 151.20 0.000 152.22 0.000 151.22 0.000 152.24 0.000 151.24 0.000 152.26 0.000 151.26 0.000 152.28 0.000 151.28 0.000 152.30 0.000 151.30 0.000 152.32 0.000 151.32 0.000 152.34 0.000 151.34 0.000 152.36 0.000 151.36 0.000 152.38 0.000 151.38 0.000 152.40 0.000 151.40 0.000 152.42 0.000 151.42 0.000 152.44 0.000 151.44 0.000 152.46 0.000 151.46 0.000 152.48 0.000 151.48 0.000 152.50 0.000 151.50 0.000 152.52 0.000 151.52 0.000 152.54 0.000 151.54 0.000 152.56 0.000 151.56 0.000 152.58 0.000 151.58 0.000 152.60 0.000 151.60 0.000 152.62 0.000 151.62 0.000 152.64 0.000 151.64 0.000 152.66 0.000 151.66 0.000 152.68 0.000 151.68 0.000 152.70 0.000 151.70 0.000 152.72 0.000 151.72 0.000 152.74 0.000 151.74 0.000 152.76 0.000 151.76 0.000 152.78 0.000 151.78 0.000 152.80 0.000 151.80 0.000 152.82 0.000 151.82 0.000 152.84 0.000 151.84 0.000 152.86 0.000 151.86 0.000 152.88 0.000 151.88 0.000 152.90 0.000 151.90 0.000 152.92 0.000 POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 97 Summary for Pond P2: VEGETATED DETENTION 02 Inflow Area = 0.989 ac, 19.40% Impervious, Inflow Depth = 2.55" for 25-yr event Inflow = 2.29 cfs @ 12.21 hrs, Volume= 0.210 of Outflow = 2.29 cfs @ 12.22 hrs, Volume= 0.210 af, Atten= 0%, Lag= 0.4 min Discarded = 0.00 cfs @ 12.22 hrs, Volume= 0.003 of Primary = 2.29 cfs @ 12.22 hrs, Volume= 0.207 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 154.32'@ 12.22 hrs Surf.Area= 225 sf Storage= 101 cf Plug-Flow detention time=7.8 min calculated for 0.210 of(100% of inflow) Center-of-Mass det. time= 8.0 min ( 841.3 - 833.4 ) Volume Invert Avail.Storage Storage Description #1 153.60' 316 cf Custom Stage Data (Irregular)Listed below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 153.60 56 40.0 0 0 56 154.00 156 56.0 41 41 180 155.00 416 117.0 276 316 15024 Device Routing Invert Outlet Devices #1 Device 2 154.00' 15.0" Horiz. 15" GRATE C= 0.600 Limited to weir flow at low heads #2 Primary 152.10' 12.0" Round 12" HDPE L= 21.7' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 152.10'/ 151.10' S= 0.0461 T Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.79 sf #3 Discarded 153.60' 0.270 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.22 hrs HW=154.32' (Free Discharge) L3=Exfi1tration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=2.28 cfs @ 12.22 hrs HW=154.32' (Free Discharge) L2=12" HDPE (Passes 2.28 cfs of 3.91 cfs potential flow) L1=15" GRATE (Weir Controls 2.28 cfs @ 1.84 fps) POST-DEVELOPMENT 25-0039DV00—SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15 ry Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 98 Pond P2: VEGETATED DETENTION 02 Hydrograph 1 2.29 cfs EM Inflow 2.29 cfs outflow 01 ea ac Discarded 2.29 cfs Inflow Ar =0.989 0 Primary Peak Elev=154.32' %! Stora a=1 01 cf 0 0 U U U U U U U U U UU UU U U UU UU U UU UU U FVIIPllqll�IIPIIFIlPlIq��IIPIIFillillFillplIP11 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 99 Stage-Area-Storage for Pond P2: VEGETATED DETENTION 02 Elevation Surface Storage Elevation Surface Storage (feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet) 153.60 56 0 154.62 302 180 153.62 60 1 154.64 308 186 153.64 64 2 154.66 314 193 153.66 68 4 154.68 319 199 153.68 72 5 154.70 325 205 153.70 76 7 154.72 331 212 153.72 81 8 154.74 336 219 153.74 85 10 154.76 342 225 153.76 90 12 154.78 348 232 153.78 95 13 154.80 354 239 153.80 100 15 154.82 360 247 153.82 105 17 154.84 366 254 153.84 110 20 154.86 372 261 153.86 115 22 154.88 378 269 153.88 121 24 154.90 384 276 153.90 126 27 154.92 391 284 153.92 132 29 154.94 397 292 153.94 138 32 154.96 403 300 153.96 144 35 154.98 410 308 153.98 150 38 155.00 416 316 154.00 156 41 154.02 160 44 154.04 164 47 154.06 168 50 154.08 172 54 154.10 176 57 154.12 181 61 154.14 185 65 154.16 189 68 154.18 194 72 154.20 198 76 154.22 202 80 154.24 207 84 154.26 212 88 154.28 216 93 154.30 221 97 154.32 226 101 154.34 230 106 154.36 235 111 154.38 240 115 154.40 245 120 154.42 250 125 154.44 255 130 154.46 260 135 154.48 265 141 154.50 270 146 154.52 276 151 154.54 281 157 154.56 286 163 154.58 292 168 154.60 297 174 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 100 Summary for Pond P3: VEGETATED DETENTION 01 Inflow Area = 0.258 ac, 42.47% Impervious, Inflow Depth = 4.49" for 25-yr event Inflow = 1.26 cfs @ 12.08 hrs, Volume= 0.096 of Outflow = 1.24 cfs @ 12.10 hrs, Volume= 0.096 af, Atten= 2%, Lag= 0.9 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.008 of Primary = 1.23 cfs @ 12.10 hrs, Volume= 0.089 of Routed to Pond 3P : J FPD0406 (Jellyfish) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 154.49'@ 12.10 hrs Surf.Area= 438 sf Storage= 267 cf Plug-Flow detention time=73.0 min calculated for 0.096 of(100% of inflow) Center-of-Mass det. time= 73.2 min ( 867.8 - 794.6 ) Volume Invert Avail.Storage Storage Description #1 153.60' 540 cf VEGETATED DETENTION 01 (Irregullar�isted below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 153.60 195 58.0 0 0 195 154.00 272 65.0 93 93 268 155.00 650 162.0 447 540 25024 Device Routing Invert Outlet Devices #1 Device 2 154.25' 12.0" Horiz. 12" AD (Orifice/Grate) C= 0.600 Limited to weir flow at low heads #2 Primary 152.00' 10.0" Round 10" HDPE L= 48.1' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 152.00'/ 151.51' S= 0.0102 7' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #3 Discarded 153.60' 0.270 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=154.49' (Free Discharge) L3=Exfi1tration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=1.23 cfs @ 12.10 hrs HW=154.49' (Free Discharge) L2=10" HDPE (Passes 1.23 cfs of 2.99 cfs potential flow) L1=12" AD (Orifice/Grate)(Weir Controls 1.23 cfs @ 1.61 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 101 Pond P3: VEGETATED DETENTION 01 Hydrograph 1.26 cfs Inflow llll Outflow 1.24 cfs 01 Discarded Inflow Area=0.258 ac 0 Primary 1.23 cfs Peak Elev=154.49' % Storage=267 cf 1 o UL 0 ,' ,,� �,,�,,� U U UU UU 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 102 Stage-Area-Storage for Pond P3: VEGETATED DETENTION 01 Elevation Surface Storage Elevation Surface Storage (feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet) 153.60 195 0 154.62 487 325 153.62 199 4 154.64 495 335 153.64 202 8 154.66 503 345 153.66 206 12 154.68 511 355 153.68 209 16 154.70 520 365 153.70 213 20 154.72 528 376 153.72 217 25 154.74 536 387 153.74 220 29 154.76 544 397 153.76 224 34 154.78 553 408 153.78 228 38 154.80 561 419 153.80 232 43 154.82 570 431 153.82 236 47 154.84 579 442 153.84 240 52 154.86 587 454 153.86 244 57 154.88 596 466 153.88 248 62 154.90 605 478 153.90 252 67 154.92 614 490 153.92 256 72 154.94 623 502 153.94 260 77 154.96 632 515 153.96 264 82 154.98 641 528 153.98 268 88 155.00 650 540 154.00 272 93 154.02 278 98 154.04 284 104 154.06 290 110 154.08 296 116 154.10 303 122 154.12 309 128 154.14 315 134 154.16 322 140 154.18 328 147 154.20 335 154 154.22 341 160 154.24 348 167 154.26 355 174 154.28 362 181 154.30 368 189 154.32 375 196 154.34 382 204 154.36 389 211 154.38 397 219 154.40 404 227 154.42 411 235 154.44 418 244 154.46 426 252 154.48 433 261 154.50 441 269 154.52 448 278 154.54 456 287 154.56 464 297 154.58 471 306 154.60 479 315 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type/1/ 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 103 Summary for Pond SB1: P1 - STORMWATER BASIN Inflow Area = 0.841 ac, 9.22% Impervious, Inflow Depth = 3.43" for 25-yr event Inflow = 2.85 cfs @ 12.12 hrs, Volume= 0.241 of Outflow = 2.05 cfs @ 12.22 hrs, Volume= 0.241 af, Atten= 28%, Lag= 6.1 min Discarded = 0.02 cfs @ 12.22 hrs, Volume= 0.093 of Primary = 1.87 cfs @ 12.22 hrs, Volume= 0.145 of Routed to Pond P2 : VEGETATED DETENTION 02 Secondary= 0.16 cfs @ 12.22 hrs, Volume= 0.003 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 157.66'@ 12.22 hrs Surf.Area= 3,482 sf Storage= 3,386 cf Plug-Flow detention time=553.9 min calculated for 0.241 of(100% of inflow) Center-of-Mass det. time= 553.8 min ( 1,373.2 - 819.4 ) Volume Invert Avail.Storage Storage Description #1 156.50' 7,085 cf Basin (Irregular)Listed below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 156.50 21369 226.0 0 0 25369 157.00 21834 239.0 15299 15299 25864 158.00 33838 264.0 35323 45622 35896 158.60 43378 276.0 25463 75085 45436 Device Routing Invert Outlet Devices #1 Discarded 156.50' 0.270 in/hr Infiltration over Surface area #2 Primary 157.50' 12.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 #3 Device 4 157.60' 1.0" x 9.0" Horiz. 12" Orifice/Grate X 8.00 C= 0.600 in 12.0" Grate (64% open area) Limited to weir flow at low heads #4 Secondary 153.00' 12.0" Round 12" HDPE L= 50.4' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 153.00'/ 152.00' S= 0.0198 7' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 104 Discarded OutFlow Max=0.02 cfs @ 12.22 hrs HW=157.66' (Free Discharge) L1=Infiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=1.86 cfs @ 12.22 hrs HW=157.66' (Free Discharge) L2=Broad-Crested Rectangular Weir(Weir Controls 1.86 cfs @ 0.96 fps) Secondary OutFlow Max=0.16 cfs @ 12.22 hrs HW=157.66' (Free Discharge) L4=12" HDPE (Passes 0.16 cfs of 6.09 cfs potential flow) L3=12" Orifice/Grate (Weir Controls 0.16 cfs, @ 0.81 fps) Pond SB1: P1 - STORMWATER BASIN Hydrograph 2.85 cfs EM Inflow llll Outflow Inflow Area=0.841 ac Discarded Primar y 3 Peak Elev=157.66 v Secondary 2.05 cfs Storage=3,386 cf 1.87 cfs 2 ,> 0 1 i cfs 0.1 cfs 0'rnm7rn7Tnm7rR7rT7rFmT-n 0 2 4 6 8 1012 1416 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 105 Stage-Area-Storage for Pond SB1: P1 - STORMWATER BASIN Elevation Surface Storage (feet) (sq-ft) (cubic-feet) 156.50 23369 0 156.55 23414 120 156.60 23459 241 156.65 23504 365 156.70 23550 492 156.75 2596 620 156.80 2)643 751 156.85 25690 885 156.90 23738 1,020 156.95 23786 11159 157.00 23834 1,299 157.05 23881 1,442 157.10 23928 1587 157.15 23975 1,735 157.20 3,023 11885 157.25 3,071 2,037 157.30 33119 2,192 157.35 33168 2,349 157.40 33217 21508 157.45 33267 2,671 157.50 33317 2,835 157.55 33367 3,002 157.60 33418 3,172 157.65 3,469 31344 157.70 3521 3519 157.75 33573 3,696 157.80 33625 3,876 157.85 33678 41059 157.90 33731 4,244 157.95 33784 4,432 158.00 33838 4,622 158.05 33882 4,815 158.10 3,926 51011 158.15 3,970 5,208 158.20 43014 5,407 158.25 43059 5,609 158.30 43104 51813 158.35 43149 6,020 158.40 43194 6,228 158.45 43240 6,439 158.50 43286 6,652 158.55 4,332 61868 158.60 41378 77085 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 106 Summary for Link DP-1: DP-1 (EX-CB) Inflow Area = 3.490 ac, 50.18% Impervious, Inflow Depth = 4.22" for 25-yr event Inflow = 14.34 cfs @ 12.09 hrs, Volume= 1.226 of Primary = 14.34 cfs @ 12.09 hrs, Volume= 1.226 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-1: DP-1 (EX-CB) Hydrograph Inflow 16 El Primary 14.34 cfs 15 Inflow Area=3.490 ac 12 % 11 i it r r it _0 it r LL 7 6 5- 0 /r.,/,ate, 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 25-yr Rainfall=6.15" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 107 Summary for Link DP-2: DP-2 (OFF-SITE AIRFIELD) Inflow Area = 0.218 ac, 31.29% Impervious, Inflow Depth = 4.13" for 25-yr event Inflow = 1.04 cfs @ 12.09 hrs, Volume= 0.075 of Primary = 1.04 cfs @ 12.09 hrs, Volume= 0.075 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-2: DP-2 (OFF-SITE AIRFIELD) Hydrograph Inflow El ry 1.04 cfs Prima Inflow Area=0.218 ac ............. O j j MEW 0 "T"In"I IrIFIFIFIF]11�11FIPFIF]��FIPI U U UU U U U U U U U U 9 9 9 U 9 9 FFUIIF�lInlIF�'IT'IF�lln"F�llqllPl'F�llp"F�"F 111FIFIRIFIF i i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 108 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentPR-1: PR-1 Runoff Area=10,160 sf 36.37% Impervious Runoff Depth=6.03" Tc=6.0 min CN=84 Runoff=1.60 cfs 0.117 of SubcatchmentPR-10: PR-10 Runoff Area=34,216 sf 61.92% Impervious Runoff Depth=6.62" Tc=6.0 min CN=89 Runoff=5.74 cfs 0.433 of SubcatchmentPR-11: PR-11 Runoff Area=23,923 sf 40.23% Impervious Runoff Depth=6.03" Tc=6.0 min CN=84 Runoff=3.76 cfs 0.276 of SubcatchmentPR-1W:WATERSURFACE Runoff Area=1,077 sf 100.00% Impervious Runoff Depth=7.69" Tc=0.0 min CN=98 Runoff=0.23 cfs 0.016 of SubcatchmentPR-2: PR-2 Runoff Area=10,646 sf 85.97% Impervious Runoff Depth=7.33" Tc=6.0 min CN=95 Runoff=1.88 cfs 0.149 of SubcatchmentPR-3.1: PR-3.1 Runoff Area=33,659 sf 1.17% Impervious Runoff Depth=4.75" Flow Length=279' Tc=8.6 min CN=73 Runoff=3.93 cfs 0.306 of SubcatchmentPR-3.1W: PR-3.1 Runoff Area=2,985 sf 100.00% Impervious Runoff Depth=7.69" Tc=0.0 min CN=98 Runoff=0.65 cfs 0.044 of SubcatchmentPR-3.2: PR-3.2 Runoff Area=5,636 sf 74.13% Impervious Runoff Depth=6.97" Tc=6.0 min CN=92 Runoff=0.97 cfs 0.075 of SubcatchmentPR-3.2W:WATERSURFACE Runoff Area=801 sf 100.00% Impervious Runoff Depth=7.69" Tc=0.0 min CN=98 Runoff=0.17 cfs 0.012 of SubcatchmentPR-4.1: PR-4.1 Runoff Area=3,862 sf 100.00% Impervious Runoff Depth=7.69" Tc=6.0 min CN=98 Runoff=0.69 cfs 0.057 of SubcatchmentPR-4.2: PR-4.2 Runoff Area=1,596 sf 100.00% Impervious Runoff Depth=7.69" Tc=6.0 min CN=98 Runoff=0.29 cfs 0.023 of SubcatchmentPR-4.3: PR-4.3 Runoff Area=1,602 sf 100.00% Impervious Runoff Depth=7.69" Tc=6.0 min CN=98 Runoff=0.29 cfs 0.024 of SubcatchmentPR-5.1: PR-5.1 Runoff Area=9,478 sf 31.29% Impervious Runoff Depth=5.79" Tc=6.0 min CN=82 Runoff=1.45 cfs 0.105 of SubcatchmentPR-5.2: PR-5.2 Runoff Area=561 sf 0.00% Impervious Runoff Depth=4.86" Tc=6.0 min CN=74 Runoff=0.07 cfs 0.005 of SubcatchmentPR-6: PR-6 Runoff Area=3,793 sf 100.00% Impervious Runoff Depth=7.69" Tc=6.0 min C N=98 Runoff=0.68 cfs 0.056 of SubcatchmentPR-7: PR-7 Runoff Area=13,728 sf 67.61% Impervious Runoff Depth=6.74" Tc=6.0 min CN=90 Runoff=2.33 cfs 0.177 of POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 109 SubcatchmentPR-8: PR-8 Runoff Area=1,060 sf 81.51% Impervious Runoff Depth=7.21" Tc=6.0 min CN=94 Runoff=0.19 cfs 0.015 of SubcatchmentPR-9: PR-9 Runoff Area=2,728 sf 80.72% Impervious Runoff Depth=7.09" Tc=6.0 min CN=93 Runoff=0.48 cfs 0.037 of Pond 3P: JFPD0406(Jellyfish) Peak Elev=153.32' Inflow=5.29 cfs 0.416 of Primary=0.47 cfs 0.266 of Secondary=4.82 cfs 0.150 of Outflow=5.29 cfs 0.416 of Pond P2: VEGETATED DETENTION 02 Peak Bev=154.52' Storage=152 cf Inflow=4.23 cfs 0.330 of Discarded=0.00 cfs 0.003 of Primary=4.14 cfs 0.327 of Outflow=4.14 cfs 0.330 of Pond P3: VEGETATED DETENTION 01 Peak Elev=154.55' Storage=292 cf Inflow=1.72 cfs 0.133 of Discarded=0.00 cfs 0.008 of Primary=1.69 cfs 0.125 of Outflow=1.69 cfs 0.133 of Pond SB1: P1 -STORMWATERBASIN Peak Elev=157.74' Storage=3,659 cf Inflow=4.18 cfs 0.350 of Discarded=0.02 cfs 0.095 of Primary=3.39 cfs 0.243 of Secondary=0.54 cfs 0.012 of Outflow=3.95 cfs 0.350 of Link DP-1: DP-1 (EX-CB) Inflow=22.25 cfs 1.716 of Primary=22.25 cfs 1.716 of Link DP-2: DP-2(OFF-SITE AIRFIELD) Inflow=1.45 cfs 0.105 of Primary=1.45 cfs 0.105 of Total Runoff Area = 3.708 ac Runoff Volume = 1.927 of Average Runoff Depth = 6.24" 50.93% Pervious = 1.888 ac 49.07% Impervious = 1.819 ac POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 110 Summary for Subcatchment PR-1: PR-1 Runoff = 1.60 cfs @ 12.09 hrs, Volume= 0.117 af, Depth= 6.03" Routed to Pond P3 : VEGETATED DETENTION 01 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 37695 98 Paved parking HSG C 57539 74 >75% Grass cover, Good HSG C 926 89 Gravel roads, HSG C 107160 84 Weighted Average 6,465 63.63% Pervious Area 31695 36.37% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-1: PR-1 Hydrograph 1.60 cfs El Runoff Type III 24=hr 100=yr Rainfall=7.93" Runoff Area=10,160 sf Runoff Volume=0.1 17 of Runoff Depth=6.03" o % Tc=6.0 min CN=84 / 0 o 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 111 Summary for Subcatchment PR-10: PR-10 Runoff = 5.74 cfs @ 12.08 hrs, Volume= 0.433 af, Depth= 6.62" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 47033 74 >75% Grass cover, Good, HSG C 695 98 Roofs HSG C 201490 98 Paved parking HSG C 8,998 74 >75% Grass cover, Good HSG C 347216 89 Weighted Average 131031 38.08% Pervious Area 217185 61.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-10: PR-10 Hydrograph 6 5.74 cfs I El Runoff � Type III 24=h 5 / 100=yr Rainfall=7.93" � Runoff Area=34,216 sf Runoff Volume=0.433 of Runoff Depth=6.62" 0 3 Tc=6.0 min CN=89 1 / 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 112 Summary for Subcatchment PR-11: PR-11 Runoff = 3.76 cfs @ 12.09 hrs, Volume= 0.276 af, Depth= 6.03" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 474 70 Woods, Good HSG C 17340 74 >75% Grass cover, Good, HSG C 8,880 98 Paved parking HSG C 744 98 Roofs HSG C 127485 74 >75% Grass cover, Good HSG C 23,923 84 Weighted Average 141299 59.77% Pervious Area 9,624 40.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-11: PR-11 Hydrograph 4 3.76 cfs El Runoff Type III 24=hr 100=yr Rainfall=7.93" 3 ,r Runoff Area=23,923 sf Runoff Volume=0.276 of Runoff Depth=6.03" 2UL Tc=6.0 min CN=84 i 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 113 Summary for Subcatchment PR-1W: WATER SURFACE (TO VDA) Runoff = 0.23 cfs @ 12.00 hrs, Volume= 0.016 af, Depth= 7.69" Routed to Pond P3 : VEGETATED DETENTION 01 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 17077 98 Water Surface (as impervious) 17077 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-1 W: WATER SURFACE (TO VDA) Hydrograph 0.26 El Runoff 0.25 0.23 cfs 0.24 0.23 Type III 24=hr o.22 0.21 j 100 yr Rainfall=7.93 0.19 0.18 / Runoff Area 1,077 sf 0.17 / Runo ff Volume=O016 of 0.16 0.15.o 0.14 0.13 / Runoff Depth=7,69" 3 c 0.12 j minTc=0.0 �n0.11 0.11 CN=98 0.09 0.0s , / 0.05 `; 0.04 f fir/ 0.03 0.02sm 0.01 01 U U U,I'U U U U ,,r e,,,/ 0 2 4 6 8 10 12 14 16 1820 2224 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 114 Summary for Subcatchment PR-2: PR-2 Runoff = 1.88 cfs @ 12.08 hrs, Volume= 0.149 af, Depth= 7.33" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 97152 98 Paved parking HSG C 17494 74 >75% Grass cover, Good HSG C 107646 95 Weighted Average 1,494 14.03% Pervious Area 9,152 85.97% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-2: PR-2 Hydrograph 2 1.88 cfs El Runoff Type III 24=hr 100=yr Rainfall=7.93" Runoff Area=10,646 sf Runoff Volume=0.149 f a Runoff Depth=7.33" 0 1 Tc=6.0 min CN=95 / / O %,„ U U U U U U U 1111 1111 1111 1111 1111 1111 1111-U-TV-FU-TU-TT-TTT7r U TTU-VTTTTVJFTTVTTT-UTTJ[-lllr7ll7llr7ll7711711511 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 115 Summary for Subcatchment PR-3.1: PR-3.1 Runoff = 3.93 cfs @ 12.12 hrs, Volume= 0.306 af, Depth= 4.75" Routed to Pond S131 : P1 - STORMWATER BASIN Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 131226 70 Woods, Good HSG C 1,199 89 Gravel roads, HSG C 167 98 Concrete (wall/pads) 191 98 Roofs HSG C 35 98 Paved walk 181841 74 >75% Grass cover, Good, HSG C 331659 73 Weighted Average 331266 98.83% Pervious Area 393 1.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.9 33 0.0730 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.74" 2.0 17 0.0250 0.14 Sheet Flow, Grass: Short n= 0.150 P2= 3.74" 1.7 229 0.0200 2.28 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 8.6 279 Total POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 11124-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 116 Subcatchment PR-3.1: PR-3.1 Hydrograph 3.93 cfS El Runoff Type III 24=hr y 100- r Rainfall=7.93" � 3 Runoff Area�33,659 sf Runoff Volume=0.306 of Runoff Depth=4.75" .22 Flow Len 2gth=279'�� Tc=8.6 miry CN=73 1 i r / 0 U U U U U U UU U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 117 Summary for Subcatchment PR-3.1 W: PR-3.1 Runoff = 0.65 cfs @ 12.00 hrs, Volume= 0.044 af, Depth= 7.69" Routed to Pond S131 : P1 - STORMWATER BASIN Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 27985 98 Water Surface (as Impervious) 27985 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-3.1 W: PR-3.1 Hydrograph El if 0.7 0.65 cfs Run o 0.65 Type III 24=hr 0.6 100=yr Rainfall=7.93" 0.55 0.5 / Runoff Area=2,985 sf 0.45 Runoff Volume=0.044 of 0.4 "Runoff Depth=7,69 3 0.35 Tc=0.0 min 0.3 CN=98 0.15 it 0.1 0.05 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 118 Summary for Subcatchment PR-3.2: PR-3.2 Runoff = 0.97 cfs @ 12.08 hrs, Volume= 0.075 af, Depth= 6.97" Routed to Pond P2 : VEGETATED DETENTION 02 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 47178 98 Paved parking HSG C 17458 74 >75% Grass cover, Good HSG C 57636 92 Weighted Average 17458 25.87% Pervious Area 4,178 74.13% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3.2: PR-3.2 Hydrograph 0.97 cfs El Runoff 1 Type III 24=hr 100=yr Rainfall=7.93" NO Runoff Area=5,636 sf Runoff Volume=0.075 of Runoff Depth=6.97" 0 Tc=6.0 min CN=92 ram/ O %'/n r///i it, a u / c i,%%i i a ur /u /i //i lF a U U U U U U U U U U U U T U U U U U U U U U U U U U U U 1111 1111 1111 1111 1111 1111 1111 U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U 1111 1111 1111 1111 1111 1111 11111111 U U U U U U U U U U U U U U U U U U U U U U U U U U U U 1111 1111 1111 1111 1111 11111111 1111 U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U 1111 1111 11111111 1111 1111 1111 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 119 Summary for Subcatchment PR-3.2W: WATER SURFACE (TO VDA) Runoff = 0.17 cfs @ 12.00 hrs, Volume= 0.012 af, Depth= 7.69" Routed to Pond P2 : VEGETATED DETENTION 02 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 801 98 Water Surface (as impervious) 801 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, Subcatchment PR-3.2W: WATER SURFACE (TO VDA) Hydrograph 0.19 0.17 cfs El Runoff 0.18 0.17 Type III 24=hr 0.16 1100myr Rainfall=7.93 0. - RunoffArea=801 fs 0.13 0.12 Runoff Vol u me=0.012 of 0.11 Runoff Deth=7,69" 0.1 % p 3 0 0.09 Tc=0.0m n 0.08 j 0.07 CN=98 0.06 0.04 i ; 0.03 0.02 0.01 01 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 120 Summary for Subcatchment PR-4.1: PR-4.1 Runoff = 0.69 cfs @ 12.08 hrs, Volume= 0.057 af, Depth= 7.69" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 37862 98 Roofs H S G C 37862 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.1: PR-4.1 Hydrograph 0.75 0.69 cfs El Runoff 0.7 Type III 24=hr 0.65 ,/ 100=yr Rainfall=7.93" Runoff Area=3,862 sf i 0.5 Runoff 05 Volume=0. 7 of .. 0.45 0.4 ! Runoff Depth=7,69" o 0.35 Tc=6.0 min /. CN=98 0.25 % 0.2 0.15 0.1 0.05 011 0 2 4 6 8 10 12 14 16 18 20 2224 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 6668 7072 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 121 Summary for Subcatchment PR-4.2: PR-4.2 Runoff = 0.29 cfs @ 12.08 hrs, Volume= 0.023 af, Depth= 7.69" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 17596 98 Roofs H S G C 17596 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.2: PR-4.2 Hydrograph 0.3 0.29 cfs El Runoff 0.28 Type III 24=hr 100myr Rainfall=7.93" 0.24 0.22 Runoff Area=1 596 sf i 0.2 Runoff Volume=0.023of .� 0.18 o Runoff Depth=7,69" 3 0.16 o Tc=6.0 min 0.12 CN=98 0.1 % 0.08 0.04 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 122 Summary for Subcatchment PR-4.3: PR-4.3 Runoff = 0.29 cfs @ 12.08 hrs, Volume= 0.024 af, Depth= 7.69" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 17602 98 Roofs H S G C 17602 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4.3: PR-4.3 Hydrograph 0.32 - - - - - - - _ _ _ Runoff 0.3 0.29 cfs � 0.28 % Type III 24=hr 0.26 100myr Rainfall=7.93" 0.24 0.22 Runoff Area=1,602 sf i 0.2 Runoff Volume=,0.024 of VON' 0.18 %o Runoff Depth=7,69" 3 0.16 % C 0.14 Tc=6.0 min 0.12 CN=98 0.1 j 0.06 0.04 �! 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 123 Summary for Subcatchment PR-5.1: PR-5.1 Runoff = 1.45 cfs @ 12.09 hrs, Volume= 0.105 af, Depth= 5.79" Routed to Link DP-2 : DP-2 (OFF-SITE AIRFIELD) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 27966 98 Paved parking HSG C 67512 74 >75% Grass cover, Good HSG C 97478 82 Weighted Average 67512 68.71% Pervious Area 2,966 31.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5.1: PR-5.1 Hydrograph 1.45 cfs El Runoff Type III 24=hr y � 100= r Rainfall=7.93" Runoff Area=9,478 sf 1 Runoff Volume=0.105 of Runoff Depth=5.79" ,0 Tc=6.0 min CN=82 O 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 124 Summary for Subcatchment PR-5.2: PR-5.2 Runoff = 0.07 cfs @ 12.09 hrs, Volume= 0.005 af, Depth= 4.86" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 561 74 >75% Grass cover, Good HSG C 561 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5.2: PR-5.2 Hydrograph 0.08 El Runoff0.07 cfs 0.075 ,�0.07 Type III 24=hr % 0.065 j 100=yr Rainfall=7.937 0.06 j Runoff Area=561 sf 0.055,11111111 0.05 Runoff Volume=0.005 of 0.045 .� Runoff Depth=4.86" 3 0.04 % Tc=6,0-m n 0.035 0.03 ' CN=74 0.025 0.02 j5,1111111111111 0.01 0.005 44 �' / 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 125 Summary for Subcatchment PR-6: PR-6 Runoff = 0.68 cfs @ 12.08 hrs, Volume= 0.056 af, Depth= 7.69" Routed to Pond 3P : J FPD0406 (Jellyfish) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 37793 98 Paved parking HSG C 37793 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-6: PR-6 Hydrograph 0.75 Runoff 0.68 cfs 0.7 0.65 Type III 24=hr �� 0.6 100=yr Rainfall=7.93" 0.55 Runoff Area=3 793 sf 0.5 Runoff Volume=0.056 of 0.4 Runoff Depth=7,69" 0 0.35 Tc=6.0 min 0.3 CN=98 0.25 0.2 0.15 0.1 0.05 0 0 2 4 6 8 10 12 14 16 18 20 22 24 2628 3032 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 126 Summary for Subcatchment PR-7: PR-7 Runoff = 2.33 cfs @ 12.08 hrs, Volume= 0.177 af, Depth= 6.74" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 97281 98 Paved parking HSG C 47447 74 >75% Grass cover, Good, HSG C 137728 90 Weighted Average 4,447 32.39% Pervious Area 9,281 67.61% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-7: PR-7 Hydrograph 2.33 cfs El Runoff Type III 24=hr 2 / 100=yr Rainfall=7.93" Runoff Area=13,728 sf Runoff Volume=0.177 of Runoff Depth=6.74" 0 3 Tc=6.0 min 1 CN=90 0 U U U U U U UU U U U U U U U U UU U U U U U U U U U FUFFMq1�11FIFIFIF]j�11 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 127 Summary for Subcatchment PR-8: PR-8 Runoff = 0.19 cfs @ 12.08 hrs, Volume= 0.015 af, Depth= 7.21" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 864 98 Paved parking HSG C 196 74 >75% Grass cover, Good HSG C 17060 94 Weighted Average 196 18.49% Pervious Area 864 81.51% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-8: PR-8 Hydrograph El Runoff 0.2 0.19 cfs 0.19 0.18Type III 24=hr 0.17 0.16 / 100=yr Rainfall�7.93" 0.15 Runoff Area=1,060 sf 0.14 0.13 n f Volume=0.015 Ru offa 0.12 Runoff Depth=7,21 0.1 0 - 0.09 Tc=6.0 min / 0.08 CN=94 0.07 0.06 0.05 - - - - - - - 0.04 0.03 0.02 / 0.01 / U U UU U U U UU U U U U U U U U UU U U U U U U U U UU U U U 1111 1111 1111 11111111 11111111 1111 U U U U U U U UU U U U UU U U U U U U U U UU U U U U U U U U mg 1111 1111 1111 1111 1111 U UU U U U U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 128 Summary for Subcatchment PR-9: PR-9 Runoff = 0.48 cfs @ 12.08 hrs, Volume= 0.037 af, Depth= 7.09" Routed to Link DP-1 : DP-1 (EX-CB) Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type III 24-hr 100-yr Rainfall=7.93" Area (sf) CN Description 27202 98 Paved parking HSG C 526 74 >75% Grass cover, Good HSG C 27728 93 Weighted Average 526 19.28% Pervious Area 2,202 80.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-9: PR-9 Hydrograph 0.5 0.48 cfs 0 Runoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . �� % - - - _ _ �� - �� Type0.45 III 24=h 100myr Rainfall=7.93" Runoff Area=2,728 sf Runoff Volume=0.037 of 0.3 Runoff Depth=7,09" 0 0.25 Tc=6.0 min 0.2 CN=93 0.15 // 0.1 0.05 iIMI 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 129 Summary for Pond 3P: JFPD0406 (Jellyfish) Inflow Area = 0.728 ac, 73.12% Impervious, Inflow Depth = 6.86" for 100-yr event Inflow = 5.29 cfs @ 12.09 hrs, Volume= 0.416 of Outflow = 5.29 cfs @ 12.09 hrs, Volume= 0.416 af, Atten= 0%, Lag= 0.0 min Primary = 0.47 cfs @ 11.30 hrs, Volume= 0.266 of Routed to Link DP-1 : DP-1 (EX-CB) Secondary= 4.82 cfs @ 12.09 hrs, Volume= 0.150 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 153.32'@ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 150.90' JF CSV File Head (feet) 0.00 0.08 0.17 0.25 0.33 0.42 0.50 0.58 0.67 0.75 0.83 0.92 1.00 1.08 1.17 1.25 1.33 1.42 1.50 1.58 1.67 1.75 Disch. (cfs) 0.000 0.003 0.006 0.010 0.013 0.016 0.019 0.049 0.079 0.109 0.139 0.169 0.199 0.229 0.258 0.288 0.318 0.348 0.378 0.408 0.438 0.468 #2 Secondary 152.65' 2.8' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 Primary OutFlow Max=0.47 cfs @ 11.30 hrs HW=152.65' (Free Discharge) L1=JF CSV File (Custom Controls 0.47 cfs) Secondary OutFlow Max=4.81 cfs @ 12.09 hrs HW=153.32' (Free Discharge) L2=Broad-Crested Rectangular Weir(Weir Controls 4.81 cfs @ 2.58 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 130 Pond 3P: JFPD0406 (Jellyfish) Hydrograph 5.29 cfs EM Inflow 5.29 cfs II II llll outflow Primary Inflow Area=0.728 ac El secondary 4.82 cfs Peak Elev=153.32' 5 10, 3 o 00 UL o cfs 0 0 2 4 6 8 10 1214 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 131 Stage-Area-Storage for Pond 3P: JFPD0406 (Jellyfish) Elevation Storage Elevation Storage Elevation Storage (feet) (acre-feet) (feet) (acre-feet) (feet) (acre-feet) 150.90 0.000 151.92 0.000 152.94 0.000 150.92 0.000 151.94 0.000 152.96 0.000 150.94 0.000 151.96 0.000 152.98 0.000 150.96 0.000 151.98 0.000 153.00 0.000 150.98 0.000 152.00 0.000 153.02 0.000 151.00 0.000 152.02 0.000 153.04 0.000 151.02 0.000 152.04 0.000 153.06 0.000 151.04 0.000 152.06 0.000 153.08 0.000 151.06 0.000 152.08 0.000 153.10 0.000 151.08 0.000 152.10 0.000 153.12 0.000 151.10 0.000 152.12 0.000 153.14 0.000 151.12 0.000 152.14 0.000 153.16 0.000 151.14 0.000 152.16 0.000 153.18 0.000 151.16 0.000 152.18 0.000 153.20 0.000 151.18 0.000 152.20 0.000 153.22 0.000 151.20 0.000 152.22 0.000 153.24 0.000 151.22 0.000 152.24 0.000 153.26 0.000 151.24 0.000 152.26 0.000 153.28 0.000 151.26 0.000 152.28 0.000 153.30 0.000 151.28 0.000 152.30 0.000 153.32 0.000 151.30 0.000 152.32 0.000 151.32 0.000 152.34 0.000 151.34 0.000 152.36 0.000 151.36 0.000 152.38 0.000 151.38 0.000 152.40 0.000 151.40 0.000 152.42 0.000 151.42 0.000 152.44 0.000 151.44 0.000 152.46 0.000 151.46 0.000 152.48 0.000 151.48 0.000 152.50 0.000 151.50 0.000 152.52 0.000 151.52 0.000 152.54 0.000 151.54 0.000 152.56 0.000 151.56 0.000 152.58 0.000 151.58 0.000 152.60 0.000 151.60 0.000 152.62 0.000 151.62 0.000 152.64 0.000 151.64 0.000 152.66 0.000 151.66 0.000 152.68 0.000 151.68 0.000 152.70 0.000 151.70 0.000 152.72 0.000 151.72 0.000 152.74 0.000 151.74 0.000 152.76 0.000 151.76 0.000 152.78 0.000 151.78 0.000 152.80 0.000 151.80 0.000 152.82 0.000 151.82 0.000 152.84 0.000 151.84 0.000 152.86 0.000 151.86 0.000 152.88 0.000 151.88 0.000 152.90 0.000 151.90 0.000 152.92 0.000 POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 132 Summary for Pond P2: VEGETATED DETENTION 02 Inflow Area = 0.989 ac, 19.40% Impervious, Inflow Depth = 4.00" for 100-yr event Inflow = 4.23 cfs @ 12.14 hrs, Volume= 0.330 of Outflow = 4.14 cfs @ 12.16 hrs, Volume= 0.330 af, Atten= 2%, Lag= 1.4 min Discarded = 0.00 cfs @ 12.16 hrs, Volume= 0.003 of Primary = 4.14 cfs @ 12.16 hrs, Volume= 0.327 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 154.52'@ 12.16 hrs Surf.Area= 276 sf Storage= 152 cf Plug-Flow detention time=5.3 min calculated for 0.330 of(100% of inflow) Center-of-Mass det. time= 5.4 min ( 831.0 - 825.6 ) Volume Invert Avail.Storage Storage Description #1 153.60' 316 cf Custom Stage Data (Irregular)Listed below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 153.60 56 40.0 0 0 56 154.00 156 56.0 41 41 180 155.00 416 117.0 276 316 15024 Device Routing Invert Outlet Devices #1 Device 2 154.00' 15.0" Horiz. 15" GRATE C= 0.600 Limited to weir flow at low heads #2 Primary 152.10' 12.0" Round 12" HDPE L= 21.7' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 152.10'/ 151.10' S= 0.0461 T Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.79 sf #3 Discarded 153.60' 0.270 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.16 hrs HW=154.52' (Free Discharge) L3=Exfi1tration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=4.14 cfs @ 12.16 hrs HW=154.52' (Free Discharge) L2=12" HDPE (Inlet Controls 4.14 cfs @ 5.27 fps) L1=15" GRATE (Passes 4.14 cfs of 4.27 cfs potential flow) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 133 Pond P2: VEGETATED DETENTION 02 Hydrograph 4.23 cfs Inflow 4.14 cfs I°°ullll outflow Discarded Inflow Area=0.989 ac Primary 4.14 cfs Peak Elev=154.52' Storage=1 52 cf 3 rr O j 1 o�r 0 r fs r r 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 134 Stage-Area-Storage for Pond P2: VEGETATED DETENTION 02 Elevation Surface Storage Elevation Surface Storage (feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet) 153.60 56 0 154.62 302 180 153.62 60 1 154.64 308 186 153.64 64 2 154.66 314 193 153.66 68 4 154.68 319 199 153.68 72 5 154.70 325 205 153.70 76 7 154.72 331 212 153.72 81 8 154.74 336 219 153.74 85 10 154.76 342 225 153.76 90 12 154.78 348 232 153.78 95 13 154.80 354 239 153.80 100 15 154.82 360 247 153.82 105 17 154.84 366 254 153.84 110 20 154.86 372 261 153.86 115 22 154.88 378 269 153.88 121 24 154.90 384 276 153.90 126 27 154.92 391 284 153.92 132 29 154.94 397 292 153.94 138 32 154.96 403 300 153.96 144 35 154.98 410 308 153.98 150 38 155.00 416 316 154.00 156 41 154.02 160 44 154.04 164 47 154.06 168 50 154.08 172 54 154.10 176 57 154.12 181 61 154.14 185 65 154.16 189 68 154.18 194 72 154.20 198 76 154.22 202 80 154.24 207 84 154.26 212 88 154.28 216 93 154.30 221 97 154.32 226 101 154.34 230 106 154.36 235 111 154.38 240 115 154.40 245 120 154.42 250 125 154.44 255 130 154.46 260 135 154.48 265 141 154.50 270 146 154.52 276 151 154.54 281 157 154.56 286 163 154.58 292 168 154.60 297 174 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 135 Summary for Pond P3: VEGETATED DETENTION 01 Inflow Area = 0.258 ac, 42.47% Impervious, Inflow Depth = 6.19" for 100-yr event Inflow = 1.72 cfs @ 12.08 hrs, Volume= 0.133 of Outflow = 1.69 cfs @ 12.09 hrs, Volume= 0.133 af, Atten= 2%, Lag= 0.9 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.008 of Primary = 1.69 cfs @ 12.09 hrs, Volume= 0.125 of Routed to Pond 3P : J FPD0406 (Jellyfish) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 154.55'@ 12.09 hrs Surf.Area= 460 sf Storage= 292 cf Plug-Flow detention time=55.6 min calculated for 0.133 of(100% of inflow) Center-of-Mass det. time= 55.6 min ( 842.1 - 786.5 ) Volume Invert Avail.Storage Storage Description #1 153.60' 540 cf VEGETATED DETENTION 01 (Irregullar�isted below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 153.60 195 58.0 0 0 195 154.00 272 65.0 93 93 268 155.00 650 162.0 447 540 25024 Device Routing Invert Outlet Devices #1 Device 2 154.25' 12.0" Horiz. 12" AD (Orifice/Grate) C= 0.600 Limited to weir flow at low heads #2 Primary 152.00' 10.0" Round 10" HDPE L= 48.1' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 152.00'/ 151.51' S= 0.0102 7' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #3 Discarded 153.60' 0.270 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=154.55' (Free Discharge) L3=Exfi1tration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=1.68 cfs @ 12.09 hrs HW=154.55' (Free Discharge) L2=10" HDPE (Passes 1.68 cfs of 3.03 cfs potential flow) L1=12" AD (Orifice/Grate)(Weir Controls 1.68 cfs @ 1.79 fps) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 136 Pond P3: VEGETATED DETENTION 01 Hydrograph 1.72 cfs EM Inflow llll Outflow 1.69 cfs _ Discarded Inflow Area=0.258 ac Primary 1.69 cfs Peak Elev=154.55' Storage=292 cf v o r r/ cfs 0 1111 U „-i.„- i.,,;,, ;/',/„✓.,i/,'ir/, f/„ /i. ./.,-i./,i /i':,/.,i is i, a� //.,./�>%,!, ./�./ i 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 137 Stage-Area-Storage for Pond P3: VEGETATED DETENTION 01 Elevation Surface Storage Elevation Surface Storage (feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet) 153.60 195 0 154.62 487 325 153.62 199 4 154.64 495 335 153.64 202 8 154.66 503 345 153.66 206 12 154.68 511 355 153.68 209 16 154.70 520 365 153.70 213 20 154.72 528 376 153.72 217 25 154.74 536 387 153.74 220 29 154.76 544 397 153.76 224 34 154.78 553 408 153.78 228 38 154.80 561 419 153.80 232 43 154.82 570 431 153.82 236 47 154.84 579 442 153.84 240 52 154.86 587 454 153.86 244 57 154.88 596 466 153.88 248 62 154.90 605 478 153.90 252 67 154.92 614 490 153.92 256 72 154.94 623 502 153.94 260 77 154.96 632 515 153.96 264 82 154.98 641 528 153.98 268 88 155.00 650 540 154.00 272 93 154.02 278 98 154.04 284 104 154.06 290 110 154.08 296 116 154.10 303 122 154.12 309 128 154.14 315 134 154.16 322 140 154.18 328 147 154.20 335 154 154.22 341 160 154.24 348 167 154.26 355 174 154.28 362 181 154.30 368 189 154.32 375 196 154.34 382 204 154.36 389 211 154.38 397 219 154.40 404 227 154.42 411 235 154.44 418 244 154.46 426 252 154.48 433 261 154.50 441 269 154.52 448 278 154.54 456 287 154.56 464 297 154.58 471 306 154.60 479 315 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type 111 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 138 Summary for Pond SB1: P1 - STORMWATER BASIN Inflow Area = 0.841 ac, 9.22% Impervious, Inflow Depth = 4.99" for 100-yr event Inflow = 4.18 cfs @ 12.12 hrs, Volume= 0.350 of Outflow = 3.95 cfs @ 12.15 hrs, Volume= 0.350 af, Atten= 5%, Lag= 2.0 min Discarded = 0.02 cfs @ 12.15 hrs, Volume= 0.095 of Primary = 3.39 cfs @ 12.15 hrs, Volume= 0.243 of Routed to Pond P2 : VEGETATED DETENTION 02 Secondary= 0.54 cfs @ 12.15 hrs, Volume= 0.012 of Routed to Link DP-1 : DP-1 (EX-CB) Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 157.74'@ 12.15 hrs Surf.Area= 3,562 sf Storage= 3,659 cf Plug-Flow detention time=388.6 min calculated for 0.350 of(100% of inflow) Center-of-Mass det. time= 388.9 min ( 1,199.4 - 810.5 ) Volume Invert Avail.Storage Storage Description #1 156.50' 7,085 cf Basin (Irregular)Listed below(Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 156.50 21369 226.0 0 0 25369 157.00 21834 239.0 15299 15299 25864 158.00 33838 264.0 35323 45622 35896 158.60 43378 276.0 25463 75085 45436 Device Routing Invert Outlet Devices #1 Discarded 156.50' 0.270 in/hr Infiltration over Surface area #2 Primary 157.50' 12.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 #3 Device 4 157.60' 1.0" x 9.0" Horiz. 12" Orifice/Grate X 8.00 C= 0.600 in 12.0" Grate (64% open area) Limited to weir flow at low heads #4 Secondary 153.00' 12.0" Round 12" HDPE L= 50.4' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 153.00'/ 152.00' S= 0.0198 7' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 139 Discarded OutFlow Max=0.02 cfs @ 12.15 hrs HW=157.74' (Free Discharge) L1=Infiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=3.39 cfs @ 12.15 hrs HW=157.74' (Free Discharge) L2=Broad-Crested Rectangular Weir(Weir Controls 3.39 cfs @ 1.18 fps) Secondary OutFlow Max=0.53 cfs @ 12.15 hrs HW=157.74' (Free Discharge) L4=12" HDPE (Passes 0.53 cfs of 6.15 cfs potential flow) L3=12" Orifice/Grate (Weir Controls 0.53 cfs @ 1.22 fps) Pond SB1: P1 - STORMWATER BASIN Hydrograph 4.18 cfs EM Inflow Outflow 3.95 cfs Inflow Area=0.841 ac Discarded a Primary Peak Elev=157.74' secondary 4 3 39cf o ra s g St a=3 659 cf i j to �; t ' 3 1 0.54 cfs cfs 011 0 2 4 6 8 1012 1416 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Revl Type 11124-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 140 Stage-Area-Storage for Pond SB1: P1 - STORMWATER BASIN Elevation Surface Storage (feet) (sq-ft) (cubic-feet) 156.50 23369 0 156.55 23414 120 156.60 23459 241 156.65 23504 365 156.70 23550 492 156.75 2596 620 156.80 2)643 751 156.85 25690 885 156.90 23738 1,020 156.95 23786 11159 157.00 23834 1,299 157.05 23881 1,442 157.10 23928 1587 157.15 23975 1,735 157.20 3,023 11885 157.25 3,071 2,037 157.30 33119 2,192 157.35 33168 2,349 157.40 33217 21508 157.45 33267 2,671 157.50 33317 2,835 157.55 33367 3,002 157.60 33418 3,172 157.65 3,469 31344 157.70 3521 3519 157.75 33573 3,696 157.80 33625 3,876 157.85 33678 41059 157.90 33731 4,244 157.95 33784 4,432 158.00 33838 4,622 158.05 33882 4,815 158.10 3,926 51011 158.15 3,970 5,208 158.20 43014 5,407 158.25 43059 5,609 158.30 43104 51813 158.35 43149 6,020 158.40 43194 6,228 158.45 43240 6,439 158.50 43286 6,652 158.55 4,332 61868 158.60 41378 77085 POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 141 Summary for Link DP-1: DP-1 (EX-CB) Inflow Area = 3.490 ac, 50.18% Impervious, Inflow Depth = 5.90" for 100-yr event Inflow = 22.25 cfs @ 12.09 hrs, Volume= 1.716 of Primary = 22.25 cfs @ 12.09 hrs, Volume= 1.716 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-1: DP-1 (EX-CB) Hydrograph EM Inflow 2 E Primary 24 2.25 cfs 23 Inflow'Area=1490 ac 22 21 20 19 18 17 / 14 - 13 3 12 i 11 10 9 8 7 6' �i 3" 2 �ii I W=114110140 U U%U U U U U U U 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) POST-DEVELOPMENT 25-0039DV00_SPR-Rev1 Type /// 24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/10/2026 HydroCAD® 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Page 142 Summary for Link DP-2: DP-2 (OFF-SITE AIRFIELD) Inflow Area = 0.218 ac, 31.29% Impervious, Inflow Depth = 5.79" for 100-yr event Inflow = 1.45 cfs @ 12.09 hrs, Volume= 0.105 of Primary = 1.45 cfs @ 12.09 hrs, Volume= 0.105 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link DP-2: DP-2 (OFF-SITE AIRFIELD) Hydrograph 1-1_45Inflow El Primary 1.45 cfs Inflow Area=0.218 ac o 0 U UU U U U UU U U U UU U TY-FFFMIIF�'IT'IF�lln"F�Illr"F�"F�"F�IIF-]Il�IIF�IIPIIF�IIF]��IIF�11PI17rrrrrrrrrrrrrr7rr=U 1111 11111111 1111 U 1111 11111111 1111 1111 11111111 1111 1111 11111111 1111 1111 1111 1 1 1 U I I I I U I I I I U I I I I U I 11111 1111 U 1111 11111111 1111 U 1111 11111111 1111 1111 11111111 1111 1111 1111 11111111 1111 U I I I I U I I I I U I I I I U I I I I U 1111 1111 1111 1111 U 1111 11111111 1111 1111 11111111 1111 1111 11111111 1111 1111 1111 11111 1 U I I I I 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) Appendix F-MassDEP Stormwater Checklist 0 Stormwater Report—LWM Administration Building—492 Sutton Street Page 28 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checkl'ist f Stormwater Report A. Introduction Important:When A Stormwater Report must be submitted with the Notice of Intent permit application to document filling out forms compliance with the Stormwater Management Standards. The following checklist is NOT a substitute for on the computer, theStormwater Report ormwaer e (which sou provide more substantive and detailed information use only the tabp ( p ) but is offered key to move your here as a tool to help the applicant organize their Stormwater Management documentation for their cursor-do not Report and for the reviewer to assess this information in a consistent format. As noted in the Checklist, use the return the Stormwater Report must contain the engineering computations and supporting information set forth in key. Volume 3 of the Massachusetts Stormwater Handbook. The Stormwater Report must be prepared and certified by a Registered Professional Engineer(RPE)licensed in the Commonwealth. The Stormwater Report must include: • The Stormwater Checklist completed and stamped by a Registered Professional Engineer(see page 2)that certifies that the Stormwater Report contains all required submittals.' This Checklist is to be used as the cover for the completed Stormwater Report. • Applicant/Project Name • Project Address • Name of Firm and Registered Professional Engineer that prepared the Report • Long-Term Pollution Prevention Plan required by Standards 4-6 • Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan required by Standard 82 • Operation and Maintenance Plan required by Standard 9 In addition to all plans and supporting information, the Stormwater Report must include a brief narrative describing stormwater management practices, including environmentally sensitive site design and LID techniques, along with a diagram depicting runoff through the proposed BMP treatment train. Plans are required to show existing and proposed conditions, identify all wetland resource areas, NRCS soil types, critical areas, Land Uses with Higher Potential Pollutant Loads (LUHPPL), and any areas on the site where infiltration rate is greater than 2.4 inches per hour. The Plans shall identify the drainage areas for both existing and proposed conditions at a scale that enables verification of supporting calculations. As noted in the Checklist, the Stormwater Management Report shall document compliance with each of the Stormwater Management Standards as provided in the Massachusetts Stormwater Handbook. The soils evaluation and calculations shall be done using the methodologies set forth in Volume 3 of the Massachusetts Stormwater Handbook. To ensure that the Stormwater Report is complete, applicants are required to fill in the Stormwater Report Checklist by checking the box to indicate that the specified information has been included in the Stormwater Report. If any of the information specified in the checklist has not been submitted, the applicant must provide an explanation. The completed Stormwater Report Checklist and Certification must be submitted with the Stormwater Report. The Stormwater Report may also include the Illicit Discharge Compliance Statement required by Standard 10. If not included in the Stormwater Report,the Illicit Discharge Compliance Statement must be submitted prior to the discharge of stormwater runoff to the post-construction best management practices. 2 For some complex projects, it may not be possible to include the Construction Period Erosion and Sedimentation Control Plan in the Stormwater Report. In that event,the issuing authority has the discretion to issue an Order of Conditions that approves the project and includes a condition requiring the proponent to submit the Construction Period Erosion and Sedimentation Control Plan before commencing any land disturbance activity on the site. swcheck.doc•04/01/08 Stormwater Report Checklist•Page 1 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checkl'ist f Stormwater Report B. Stormwater Checklist and Certification The following checklist is intended to serve as a guide for applicants as to the elements that ordinarily need to be addressed in a complete Stormwater Report. The checklist is also intended to provide conservation commissions and other reviewing authorities with a summary of the components necessary for a comprehensive Stormwater Report that addresses the ten Stormwater Standards. Note: Because stormwater requirements vary from project to project, it is possible that a complete Stormwater Report may not include information on some of the subjects specified in the Checklist. If it is determined that a specific item does not apply to the project under review, please note that the item is not applicable (N.A.)and provide the reasons for that determination. A complete checklist must include the Certification set forth below signed by the Registered Professional Engineer who prepared the Stormwater Report. Registered Professional Engineer's Certification have reviewed the Stormwater Report, including the soil evaluation, computations, Long-term Pollution Prevention Plan, the Construction Period Erosion and Sedimentation Control Plan (if included), the Long- term Post-Construction Operation and Maintenance Plan, the Illicit Discharge Compliance Statement(if included) and the plans showing the stormwater management system, and have determined that they have been prepared in accordance with the requirements of the Stormwater Management Standards as further elaborated by the Massachusetts Stormwater Handbook. I have also determined that the information presented in the Stormwater Checklist is accurate and that the information presented in the Stormwater Report accurately reflects conditions at the site as of the date of this permit application. Registered Professional Engineer Block and Signature LI ITONIII CIVIL Na. 51161 Ilt 06/16/2026 Signature and Date Checklist Project Type: Is the application for new development, redevelopment, or a mix of new and redevelopment? ❑ New development ❑ Redevelopment 0 Mix of New Development and Redevelopment swcheck.doc•04/01/08 Stormwater Report Checklist•Page 2 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) LID Measures: Stormwater Standards require LID measures to be considered. Document what environmentally sensitive design and LID Techniques were considered during the planning and design of the project: 0 No disturbance to any Wetland Resource Areas ❑ Site Design Practices (e.g. clustered development, reduced frontage setbacks) ❑ Reduced Impervious Area (Redevelopment Only) ❑ Minimizing disturbance to existing trees and shrubs ❑ LID Site Design Credit Requested: ❑ Credit 1 ❑ Credit 2 ❑ Credit 3 ❑ Use of"country drainage"versus curb and gutter conveyance and pipe ❑ Bioretention Cells (includes Rain Gardens) ❑ Constructed Stormwater Wetlands (includes Gravel Wetlands designs) ❑ Treebox Filter ❑ Water Quality Swale ❑ Grass Channel ❑ Green Roof ❑ Other(describe): Standard 1: No New Untreated Discharges 0 No new untreated discharges ❑ Outlets have been designed so there is no erosion or scour to wetlands and waters of the Commonwealth ❑ Supporting calculations specified in Volume 3 of the Massachusetts Stormwater Handbook included. swcheck.doc•04/01/08 Stormwater Report Checklist•Page 3 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checkl'ist f Stormwater Report Checklist (continued) Standard 2: Peak Rate Attenuation ❑ Standard 2 waiver requested because the project is located in land subject to coastal storm flowage and stormwater discharge is to a wetland subject to coastal flooding. ❑ Evaluation provided to determine whether off-site flooding increases during the 100-year 24-hour storm. 0 Calculations provided to show that post-development peak discharge rates do not exceed pre- development rates for the 2-year and 10-year 24-hour storms. If evaluation shows that off-site flooding increases during the 100-year 24-hour storm, calculations are also provided to show that post-development peak discharge rates do not exceed pre-development rates for the 100-year 24- hour storm. Standard 3: Recharge 0 Soil Analysis provided. 0 Required Recharge Volume calculation provided. ❑ Required Recharge volume reduced through use of the LID site Design Credits. ❑ Sizing the infiltration, BMPs is based on the following method: Check the method used. ❑ Static EK Simple Dynamic ❑ Dynamic Field' ❑ Runoff from all impervious areas at the site discharging to the infiltration BMP. x❑ Runoff from all impervious areas at the site is not discharging to the infiltration BMP and calculations are provided showing that the drainage area contributing runoff to the infiltration BMPs is sufficient to generate the required recharge volume. ❑ Recharge BMPs have been sized to infiltrate the Required Recharge Volume. 0 Recharge BMPs have been sized to infiltrate the Required Recharge Volume only to the maximum extent practicable for the following reason: ❑x Site is comprised solely of C and D soils and/or bedrock at the land surface ❑ M.G.L. c. 21 E sites pursuant to 310 CMR 40.0000 ❑ Solid Waste Landfill pursuant to 310 CMR 19.000 ❑x Project is otherwise subject to Stormwater Management Standards only to the maximum extent practicable. x❑ Calculations showing that the infiltration BMPs will drain in 72 hours are provided. ❑ Property includes a M.G.L. c. 21 E site or a solid waste landfill and a mounding analysis is included. 80%TSS removal is required prior to discharge to infiltration BMP if Dynamic Field method is used. swcheck.doc•04/01/08 Stormwater Report Checklist•Page 4 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checkl'ist f Stormwater Report Checklist (continued) Standard 3: Recharge (continued) ❑X The infiltration BMP is used to attenuate peak flows during storms greater than or equal to the 10- year 24-hour storm and separation to seasonal high groundwater is less than 4 feet and a mounding analysis is provided. ❑ Documentation is provided showing that infiltration BMPs do not adversely impact nearby wetland resource areas. Standard 4: Water Quality The Long-Term Pollution Prevention Plan typically includes the following: • Good housekeeping practices; • Provisions for storing materials and waste products inside or under cover; • Vehicle washing controls; • Requirements for routine inspections and maintenance of stormwater BMPs; • Spill prevention and response plans; • Provisions for maintenance of lawns, gardens, and other landscaped areas; • Requirements for storage and use of fertilizers, herbicides, and pesticides; • Pet waste management provisions; • Provisions for operation and management of septic systems; • Provisions for solid waste management; • Snow disposal and plowing plans relative to Wetland Resource Areas; • Winter Road Salt and/or Sand Use and Storage restrictions; • Street sweeping schedules; • Provisions for prevention of illicit discharges to the stormwater management system; • Documentation that Stormwater BMPs are designed to provide for shutdown and containment in the event of a spill or discharges to or near critical areas or from LUHPPL; • Training for staff or personnel involved with implementing Long-Term Pollution Prevention Plan; • List of Emergency contacts for implementing Long-Term Pollution Prevention Plan. 0 A Long-Term Pollution Prevention Plan is attached to Stormwater Report and is included as an attachment to the Wetlands Notice of Intent. ❑ Treatment BMPs subject to the 44% TSS removal pretreatment requirement and the one inch rule for calculating the water quality volume are included, and discharge: ❑ is within the Zone II or Interim Wellhead Protection Area ❑ is near or to other critical areas ❑ is within soils with a rapid infiltration rate (greater than 2.4 inches per hour) ❑ involves runoff from land uses with higher potential pollutant loads. ❑ The Required Water Quality Volume is reduced through use of the LID site Design Credits. 0 Calculations documenting that the treatment train meets the 80% TSS removal requirement and, if applicable, the 44% TSS removal pretreatment requirement, are provided. swcheck.doc•04/01/08 Stormwater Report Checklist•Page 5 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checki'Ist f Stormwater Report Checklist (continued) Standard 4: Water Quality (continued) ❑X The BMP is sized (and calculations provided) based on: ❑X The 1/2" or 1"Water Quality Volume or ❑ The equivalent flow rate associated with the Water Quality Volume and documentation is provided showing that the BMP treats the required water quality volume. ❑x The applicant proposes to use proprietary BMPs, and documentation supporting use of proprietary BMP and proposed TSS removal rate is provided. This documentation may be in the form of the propriety BMP checklist found in Volume 2, Chapter 4 of the Massachusetts Stormwater Handbook and submitting copies of the TARP Report, STEP Report, and/or other third party studies verifying performance of the proprietary BMPs. ❑ A TMDL exists that indicates a need to reduce pollutants other than TSS and documentation showing that the BMPs selected are consistent with the TMDL is provided. Standard 5: Land Uses With Higher Potential Pollutant Loads (LUHPPLs) ❑ The NPDES Multi-Sector General Permit covers the land use and the Stormwater Pollution Prevention Plan (SWPPP) has been included with the Stormwater Report. ❑ The NPDES Multi-Sector General Permit covers the land use and the SWPPP will be submitted prior to the discharge of stormwater to the post-construction stormwater BMPs. ❑ The NPDES Multi-Sector General Permit does not cover the land use. ❑ LUHPPLs are located at the site and industry specific source control and pollution prevention measures have been proposed to reduce or eliminate the exposure of LUHPPLs to rain, snow, snow melt and runoff, and been included in the long term Pollution Prevention Plan. ❑ All exposure has been eliminated. ❑ All exposure has not been eliminated and all BMPs selected are on MassDEP LUHPPL list. ❑ The LUHPPL has the potential to generate runoff with moderate to higher concentrations of oil and grease (e.g. all parking lots with >1000 vehicle trips per day) and the treatment train includes an oil grit separator, a filtering bioretention area, a sand filter or equivalent. Standard 6: Critical Areas ❑ The discharge is near or to a critical area and the treatment train includes only BMPs that MassDEP has approved for stormwater discharges to or near that particular class of critical area. ❑ Critical areas and BMPs are identified in the Stormwater Report. swcheck.doc•04/01/08 Stormwater Report Checklist•Page 6 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checkl'ist f Stormwater Report Checklist (continued) Standard 7: Redevelopments and Other Projects Subject to the Standards only to the maximum extent practicable ❑ The project is subject to the Stormwater Management Standards only to the maximum Extent Practicable as a: ❑ Limited Project ❑ Small Residential Projects: 5-9 single family houses or 5-9 units in a multi-family development provided there is no discharge that may potentially affect a critical area. ❑ Small Residential Projects: 2-4 single family houses or 2-4 units in a multi-family development with a discharge to a critical area ❑ Marina and/or boatyard provided the hull painting, service and maintenance areas are protected from exposure to rain, snow, snow melt and runoff ❑ Bike Path and/or Foot Path ❑ Redevelopment Project ❑x Redevelopment portion of mix of new and redevelopment. ❑x Certain standards are not fully met(Standard No. 1, 8, 9, and 10 must always be fully met) and an explanation of why these standards are not met is contained in the Stormwater Report. ❑X The project involves redevelopment and a description of all measures that have been taken to improve existing conditions is provided in the Stormwater Report. The redevelopment checklist found in Volume 2 Chapter 3 of the Massachusetts Stormwater Handbook may be used to document that the proposed stormwater management system (a) complies with Standards 2, 3 and the pretreatment and structural BMP requirements of Standards 4-6 to the maximum extent practicable and (b) improves existing conditions. Standard 8: Construction Period Pollution Prevention and Erosion and Sedimentation Control A Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan must include the following information: • Narrative; • Construction Period Operation and Maintenance Plan; • Names of Persons or Entity Responsible for Plan Compliance; 0 Construction Period Pollution Prevention Measures; • Erosion and Sedimentation Control Plan Drawings; • Detail drawings and specifications for erosion control BMPs, including sizing calculations; • Vegetation Planning; • Site Development Plan; • Construction Sequencing Plan; • Sequencing of Erosion and Sedimentation Controls; • Operation and Maintenance of Erosion and Sedimentation Controls; • Inspection Schedule; • Maintenance Schedule; • Inspection and Maintenance Log Form. ❑x A Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan containing the information set forth above has been included in the Stormwater Report. swcheck.doc•04/01/08 Stormwater Report Checklist•Page 7 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checkl'ist f Stormwater Report Checklist (continued) Standard 8: Construction Period Pollution Prevention and Erosion and Sedimentation Control (continued) ❑ The project is highly complex and information is included in the Stormwater Report that explains why it is not possible to submit the Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan with the application. A Construction Period Pollution Prevention and Erosion and Sedimentation Control has not been included in the Stormwater Report but will be submitted before land disturbance begins. ❑ The project is not covered by a NPDES Construction General Permit. ❑ The project is covered by a NPDES Construction General Permit and a copy of the SWPPP is in the Stormwater Report. ❑x The project is covered by a NPDES Construction General Permit but no SWPPP been submitted. The SWPPP will be submitted BEFORE land disturbance begins. Standard 9: Operation and Maintenance Plan ❑- The Post Construction Operation and Maintenance Plan is included in the Stormwater Report and includes the following information: ❑X Name of the stormwater management system owners; 0 Party responsible for operation and maintenance; 0 Schedule for implementation of routine and non-routine maintenance tasks; 0 Plan showing the location of all stormwater BMPs maintenance access areas; ❑ Description and delineation of public safety features; ❑ Estimated operation and maintenance budget; and 0 Operation and Maintenance Log Form. ❑ The responsible party is not the owner of the parcel where the BMP is located and the Stormwater Report includes the following submissions: ❑ A copy of the legal instrument(deed, homeowner's association, utility trust or other legal entity) that establishes the terms of and legal responsibility for the operation and maintenance of the project site stormwater BMPs; ❑ A plan and easement deed that allows site access for the legal entity to operate and maintain BMP functions. Standard 10: Prohibition of Illicit Discharges ❑ The Long-Term Pollution Prevention Plan includes measures to prevent illicit discharges; ❑x An Illicit Discharge Compliance Statement is attached; ❑ NO Illicit Discharge Compliance Statement is attached but will be submitted prior to the discharge of any stormwater to post-construction BMPs. swcheck.doc•04/01/08 Stormwater Report Checklist•Page 8 of 8 Appendix G-BMP Design Calculations Stormwater Report—LWM Administration Building—492 Sutton Street Page 29 LWMAdmin Building Appendix Stormwater Report STORMWATER CALCULATIONS BMP DESIGN ELEVATIONS&VOLUMES Stormwater Basin Bottom Elevation 156.5 ft Bottom Area 2369 sf Lowest Outlet Elevation 157.5 ft Volume 2,835.00 CF *See Stage-Storage Table Vegetated Detention 01 Bottom Elev 153.6 ft Bottom Area 195 sf Lowest Outlet Elevation 154.25 ft Volume 170.00 CF *See Stage-Storage Table Vegetated Detention 02 Bottom Elev 153.6 ft Bottom Area 56 sf Lowest Outlet Elevation 154 ft Volume 41.00 CF *See Stage-Storage Table LWM Admin Building Appendix G Stormwater Report STORMWATER CALCULATIONS-STANDARD 2 RAINFALL DATA Rainfall Data(NOAA Atlas 14) Design Storm Depth (inches) 2-year 3.16 10-year 5 25-year 6.15 100-year 7.93 LWM Admin Building Appendix G Stormwater Report STORMWATER CALCULATIONS-STANDARD 2 PEAK RATE ATTENUATION Limits of Disturbance 59,300.00 sf 1.36 ac Post-Construction Impervious 28,600.00 sf New Development 7,360.00 sf Redevelopment 21,240.00 sf Existing Analysis Area Proposed Analysis Area Runoff Area Analysis Point Runoff Area(acres) Analysis Point (acres) DP-1 3.377 DP-1 3.49 DP-2 0.331 DP-2 0.218 total 3.71 total 3.71 2-YEAR DESIGN STORM FLOWS Analysis Point Existing Flow(CFS) Proposed Flow(CFS) Net ChangeNet Change(%) (CFS) DP-1 6.26 6.29 0.03 0.48% DP-2 0.56 0.38 -0.18 -32.14% Total 6.82 6.67 -0.15 -2.20% 10-YEAR DESIGN STORM FLOWS Analysis Point Existing Flow(CFS) Proposed Flow(CFS) Net ChangeNet Change(%) (CFS) DP-1 12.15 11.24 -0.91 -7.49% DP-2 1.15 0.78 -0.37 -32.17% Total 13.3 12.02 -1.28 -9.62% 25-YEAR DESIGN STORM FLOWS Analysis Point Existing Flow(CFS) Proposed Flow(CFS) Net ChangeNet Change(%) (CFS) DP-1 15.92 14.34 -1.58 -9.92% DP-2 1.53 1.04 -0.49 -32.03% Tota l 17.45 15.38 -2.07 -11.86% 100-YEAR DESIGN STORM FLOWS Analysis Point Existing Flow(CFS) Proposed Flow(CFS) Net ChangeNet Change(%) (CFS) DP-1 21.76 22.25 0.49 2.25% DP-2 2.14 1.45 -0.69 -32.24% Total 23.9 23.7 -0.2 -0.84% LWM Admin Building Appendix G Stormwater Report STORMWATER CALCULATIONS-STANDARD 2 RUNOFF VOLUME CALCULATIONS Limits of Disturbance 59,300.00 sf 1.36 ac Post-Construction Impervious 28,600.00 sf New Development 7,360.00 sf Redevelopment 21,240.00 sf Existing Analysis Area Proposed Analysis Area Analysis Runoff Area Runoff Area(acres) Analysis Point Point (acres) DP-1 3.377 DP-1 3.49 DP-2 0.331 DP-2 0.218 total 3.71 total 3.71 2-YEAR DESIGN STORM VOLUMES Analysis Proposed Existing Volume(ac-f) Net Change(acre-ft) Net Change(%) Point Volume(ac-f) DP-1 0.474 0.456 -0.018 -3.80% DP-2 0.042 0.027 -0.015 -35.71% Total 0.516 0.483 -0.033 -6.40% 10-YEAR DESIGN STORM VOLUMES Analysis Proposed Existing Volume(ac-f) Net Change(acre-ft) Net Change(%) Point Volume(ac-f) DP-1 0.928 0.917 -0.011 -1.19% DP-2 0.085 0.056 -0.029 -34.12% Total 1.013 0.973 1 -0.04 -3.95% 25-YEAR DESIGN STORM VOLUMES Analysis Proposed Existing Volume(ac-f) Net Change(acre-ft) Net Change(%) Point Volume(ac-f) DP-1 1.227 1.226 -0.001 -0.08% DP-2 0.113 0.075 -0.038 -33.63% Total 1.34 1 1.301 1 -0.039 -2.91% 100-YEAR DESIGN STORM VOLUMES Analysis Proposed Existing Volume(ac-f) Net Change(acre-ft) Net Change(%) Point Volume(ac-f) DP-1 1.701 1.716 0.015 0.88% DP-2 0.158 0.105 -0.053 -33.54% Total 1.859 1.821 -0.038 -2.04% 25-0039DVOO SPR-Revl Type ///24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/9/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond SB1: P1 - STORMWATER BASIN Elevation Surface Storage feet s -ft cubic-feet 156.50 2 369 0 SURFACE AREA(SQ FT.) 156.55 21414 120 156.60 21459 241 156.65 21504 365 156.70 21550 492 156.75 2,596 620 156.80 2,643 751 156.85 2,690 885 156.90 21738 1,020 156.95 21786 1,159 157.00 21834 17299 157.05 21881 17442 157.10 21928 17587 157.15 2,975 17735 157.20 3,023 17885 157.25 3,071 2,037 157.30 3,119 2,192 157.35 31168 2,349 157.40 31217 21508 157.45 31267 27671 157.50 3,317 2,835 157.55 31367 37002 157.60 3,418 37172 157.65 3,469 37344 157.70 3521 3,519 157.75 3573 3,696 157.80 31625 3,876 157.85 31678 47059 157.90 31731 47244 157.95 31784 47432 158.00 31838 47622 158.05 3,882 47815 158.10 3,926 57011 158.15 3,970 5,208 158.20 41014 5,407 158.25 41059 5,609 158.30 41104 57813 158.35 41149 67020 158.40 41194 67228 158.45 41240 67439 158.50 4,286 67652 158.55 4,332 6,868 158.60 4,378 77085 25-0039DVOO SPR-Revl Type ///24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/9/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond P3: VEGETATED DETENTION 01 Elevation Surface Storage Elevation Surface Storage feet s -ft cubic-feet (feet) (sq-ft) (cubic-feet) 153.60 195 0 154.64 495 335 153.62 199 SURFACE 4 154.66 503 345 153.64 202 AREA(SF) 8 154.68 511 355 153.66 206 12 154.70 520 365 153.68 209 16 154.72 528 376 153.70 213 20 154.74 536 387 153.72 217 25 154.76 544 397 153.74 220 29 154.78 553 408 153.76 224 34 154.80 561 419 153.78 228 38 154.82 570 431 153.80 232 43 154.84 579 442 153.82 236 47 154.86 587 454 153.84 240 52 154.88 596 466 153.86 244 57 154.90 605 478 153.88 248 62 154.92 614 490 153.90 252 67 154.94 623 502 153.92 256 72 154.96 632 515 153.94 260 77 154.98 641 528 153.96 264 82 155.00 650 540 153.98 268 88 154.00 272 93 154.02 278 98 154.04 284 104 154.06 290 110 154.08 296 116 154.10 303 122 154.12 309 128 154.14 315 134 154.16 322 140 154.18 328 147 154.20 335 154 C154.26 4.24 348 167 STORAGE 154.25® 1 355 174 154.28 362 181 154.30 368 189 154.32 375 196 154.34 382 204 154.36 389 211 154.38 397 219 154.40 404 227 154.42 411 235 154.44 418 244 154.46 426 252 154.48 433 261 154.50 441 269 154.52 448 278 154.54 456 287 154.56 464 297 154.58 471 306 154.60 479 315 154.62 487 325 25-0039DVOO SPR-Revl Type ///24-hr 100-yr Rainfall=7.93" Prepared by McClure Printed 7/9/2026 HydroCADO 10.20-7a s/n 12811 ©2025 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond P2: VEGETATED DETENTION 02 Elevation Surface Storage Elevation Surface Storage (feet) cubic-feet (feet) (sq-ft) (cubic-feet) L_j5_ .60 56 0 154.64 308 186 153.62 60 SURFACE 1 154.66 314 193 153.64 64 AREA(SF) 2 154.68 319 199 153.66 68 4 154.70 325 205 153.68 72 5 154.72 331 212 153.70 76 7 154.74 336 219 153.72 81 8 154.76 342 225 153.74 85 10 154.78 348 232 153.76 90 12 154.80 354 239 153.78 95 13 154.82 360 247 153.80 100 15 154.84 366 254 153.82 105 17 154.86 372 261 153.84 110 20 154.88 378 269 153.86 115 22 154.90 384 276 153.88 121 24 154.92 391 284 153.90 126 27 154.94 397 292 153.92 132 29 154.96 403 300 153.94 138 32 154.98 410 308 153.96 144 35 155.00 416 316 153.98 150 38 U 54.0 0 156 41J VOLUME @ 154. 154.02 160 44 154.04 164 47 154.06 168 50 154.08 172 54 154.10 176 57 154.12 181 61 154.14 185 65 154.16 189 68 154.18 194 72 154.20 198 76 154.22 202 80 154.24 207 84 154.26 212 88 154.28 216 93 154.30 221 97 154.32 226 101 154.34 230 106 154.36 235 111 154.38 240 115 154.40 245 120 154.42 250 125 154.44 255 130 154.46 260 135 154.48 265 141 154.50 270 146 154.52 276 151 154.54 281 157 154.56 286 163 154.58 292 168 154.60 297 174 154.62 302 180 LWMAdmin Building Appendix Stormwater Report STORMWATER CALCULATIONS-STANDARD 3 RECHARGE CALCULATIONS REQUIRED RECHARGE VOLUME Impervious Area Pre-Development Impervious Area= 21,240 SF Post-Development Impervious Area= 28,600 SF NEW IMPERVIOUS AREA= 7,360 SF Soil Type= HSG C Target Depth Factor= 0.25 INCHES [MASSDEP RECHARGE REQUIREMENT] Total Required Recharge Volume= (0.25 inches/12)*71360 SF Total Required Recharge Volume= 153.33 JCF (Stormwater Handbook) PROPOSED RECHARGE FACILITIES Infiltration Basin Contributing Impervious Area= 1,592.00 [Rv= 33.17 ] (1,199sf Gravel roads+167sf concrete+191sf Roof+35sf pavement) Vegetated Detention Area-01 Contributing Impervious Area: 49621.00 [Rv= 96.27 ] (3,695sf Paved Parking+926sf Gravel roads) Vegetated Detention Area-02 Contributing Impervious Area: 49178.00 [Rv= 87.04 ] (4,178 sf Paved Parking) Total Impervious Area To Recharge BMPs= 10,391.00 sf [100%of New Development Impervious Area Conveyed to Recharge Areas] Designed Recharge Volumes Stormwater Basin Lowest Outlet Elev.= 157.5 Volume below overflow= 29835 CF (See Stage-Storage Table) VDA-01 Lowest Outlet Elev.= 154.25 Volume below overflow= 170 CF (See Stage-Storage Table) VDA-02 Lowest Outlet Elev.= 154 Volume below overflow= 41 CF (See Stage-Storage Table) Total Provided Recharge Volume= 3,046 CF L.WMAdmin Building Appendix Stormwater Report STORMWATER CALCULATIONS-STANDARD 3 DRAWDOWN CALCULATIONS Stormwater Basin Soil Type= Silt Loam Infiltration Rate= 0.27 inches per hour Provided Recharge Volume= 21835 CF BMP Bottom Area= 21369 SF Time(drawdown)_ (Provided Recharge Volume) / (Infiltration Rate)* (Bottom Area) =Time(drawdown)= 53.19 Hours Vegetated Detention Area 01 Soil Type= Silt Loam Infiltration Rate= 0.27 inches per hour Provided Recharge Volume= 170 CF BMP Bottom Area= 195 SF Time(drawdown)_ (Provided Recharge Volume) / (Infiltration Rate) (Bottom Area) =Time(drawdown)= 38.75 Hours Vegetated Detention Area 02 Soil Type= Silt Loam Infiltration Rate= 0.27 inches per hour Provided Recharge Volume= 41 CF BMP Bottom Area= 56 SF Time(drawdown)_ (Required Recharge Volume) / (Infiltration Rate)* (Bottom Area) =Time(drawdown)= 32.54 Hours LWMAdmin Building Appendix Stormwater Report STORMWATER CALCULATIONS-STANDARD 4 WATER QUALITY VOLUME Proposed Impervious Area= 7,360.00 SF Soil Type= HSG C Infiltration Rate=0.27 inches per hour Water Quality Depth= 0.50 inch Total Required Water Quality Volume= ['0.5"/12 x 7,360.00 ] Minimum Required Water Quality Volume= 306.67 DESIGN WATER QUALITY VOLUMES Stormwater Basin (excluded from total) Contributing Impervious Area= 1,592.00 [WQV= 66.33 cf] Lowest Outlet Elev.= 157.5 Volume below overflow= 29835 CF VDA-01 Contributing Impervious Area: 4,621.00 [WQV= 192.54 ] Lowest Outlet Elev.= 154.25 Volume below overflow= 170 CF *89%TSS Removal achieved by Downstream Manufactured Filtration Unit* VDA-02 Contributing Impervious Area: 4,178.00 [WQV= 174.08 ] Lowest Outlet Elev.= 154 Volume below overflow= 41 CF [Redevelopment:WQV met to maximum extent practicable for existing developed areas] Total Provided Water Quality Volume= 211 CF See TSS Removal Sheets LWM Admin Building Appendix G Stormwater Report STORMWATER CALCULATIONS TOTAL PHOSPHORUS REDUCTION CALCULATIONS Stormwater Basin Treatment Train Land Use Cover Type Area(sf) Area(ac) TP Load (lb/acre/yr)* Industrial Impervious 1592 0.04 1.78 Landscaped(HSG C) Pervious 21915 0.50 0.21 Forested(HSG C) Pervious 13226 0.30 0.12 SCM Load(P) 0.207 lb/year Cumulative P Load Reduction' 93% (Storage=>1"Runoff Depth) VDA-01 Treatment Train Land Use Cover Type Area(sf) Area(ac) TP Load (lb/acre/yr)* Industrial Impervious 4621 0.11 1.78 Landscaped(HSG C) Pervious 5359 0.12 0.21 SCM Load(P) 0.215 lb/year Cumulative P Load Reduction' 93% (Storage=>1"Runoff Depth) VDA-02 Treatment Train Land Use Cover Type Area(sf) Area(ac) TP Load (lb/acre/yr)* Industrial Impervious 4178 0.10 1.78 Landscaped(HSG C) Pervious 2259 0.05 0.21 SCM Load(P) 0.182 lb/year Cumulative P Load Red uction2 79% (Storage=>5"Runoff Depth) Manufactured Filtration Unit Treatment Train Land Use Cover Type Area(sf) Area(ac) TP Load (lb/acre/yr)* Industrial Impervious 18403 0.42 1.78 Landscaped(HSG C) Pervious 2055 0.05 0.21 SCM Load(P) 0.762 lb/year Cumulative P Load Red uction3 70% *Per Manufacturer Test Data *TP Loads from Table 3-1 of Attachment 3 to Appendix F of the MA MS4 General Permit. Load Reduction from Table 3-13 of Attachment 3 to Appendix F of the MA MS4 General Permit: Surface Infiltration(0.27 in/hr)BMP Performance Table for Storage equaling 1"Runoff Depth 2Load Reduction from Table 3-13 of Attachment 3 to Appendix F of the MA MS4 General Permit: Surface Infiltration(0.27 in/hr)BMP Performance Table for Storage equaling 5"Runoff Depth 3TP Load Reduction from Manufacturer's Test Data(See Appendix L) MA Draft MS4 General Permit Page F3-12 Table 3-1: Average annual distinct phosphorus (P) load export rates for use in estimating P load reduction credits in the MA MS4 Permit Phosphorus Source Category hand Surface Cover P load Export Rate, by Land Use Ibs/acre/year Commercial (COM) and Directly connected impervious 1.78 Industrial (IND) Pervious See* DevPERV Multi-Family (MFR) and Directly connected impervious 2.32 High-Density Residential (HDR) Pervious See* DevPERV Medium -Density Residential Directly connected impervious 1.96 (MDR) Pervious See* DevPERV Low Density Residential Directly connected impervious 1.52 (LDR) - "Rural" Pervious See* DevPERV Highway (HWY) Directly connected impervious 1.34 Pervious See* DevPERV Forest (FOR) Directly connected impervious 1.52 Pervious 0.13 Open Land (OPEN) Directly connected impervious 1.52 Pervious See* DevPERV Agriculture (AG) Directly connected impervious 1.52 Pervious 0.45 *Developed Land Pervious Pervious 0.03 (DevPERV)— HSG A *Developed Land Pervious Pervious 0.12 (DevPERV)— HSG B *Developed Land Pervious Pervious 0.21 (DevPERV) — HSG C *Developed Land Pervious pervious 0.29 (DevPERV)— HSG C/D *Developed Land Pervious Pervious 0.37 (DevPERV) — HSG D Notes: • For pervious areas, if the hydrologic soil group (HSG) is known, use the appropriate value from this table. If the HSG is not known, assume HSG C conditions for the phosphorus load export rate. • Agriculture includes row crops, actively managed hay fields, and pasture lands. Institutional land uses, such as government properties, hospitals and schools, are to be included in the commercial and industrial land use grouping for calculating phosphorus loading. MA Draft MS4 General Permit Page F3-54 Table 3- 15: Infiltration Basin (0.27 in/hr) SCM Performance Table Surface Infiltration (0.27 in/hr) SCM Performance Table: Long-Term Phosphorus & Nitrogen Load Reduction SCM Capacity: Depth of Runoff from Impervious ous Area 0.1 0.2 0.4 0.6 0.8 1.0 1.5 2.0 pe ea Runoff Volume Reduction 16% 30% 51% 66% 76% 82% 91% 95% Cumulative Phosphorus Load Reduction 37% 54% 74% 85% 90% 93% 98% 99% Cumulative Nitrogen Load Reduction 54% 71% 87% 93% 97% 98% 99% 100% Figure 3-10: SCM Performance Curve: Surface Infiltration (infiltration rate = 0.27 in/hr) SCM Performance Curve: Surface Infiltration (Soil infiltration rate 0.27 in/hr) Long-Term Cumulative Load Reduction based on SCM Design Storage Capacity 100% 100% At 90% 90% jr 00000 80% , , 80% 70% 70% 0 60/0 60/o E a� 50% I I 50% E M 40% I ; 40% }' O � 30/o o I I o 0 30 � /o a o I I o � 20/0 20/o 10% ; ; 10% 0% 0% 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Physical Storage Capacity: Depth of Runoff from Impervious Area (inches) Phosphorus Load Reduction Volume Nitrogen Load Reduction Appendix H - TSS Removal Calculations Stormwater Report—LWM Administration Building—492 Sutton Street Page 30 LWM Admin Building Appendix G Stormwater Report STORMWATER CALCULATIONS-STANDARD 4 TSS REMOVAL CALCULATIONS Total Impervious: 49621.00 (PR-1) Treatment Train 1 Removal Rate Removed Remaining Rain Guardian(Pre) 0% 0 1 VDA-01 80% 0.8 0.2 Jellyfish 84% 0.168 0.032 TSS Removed= 97% Total Impervious: 18,403.00 (PR-4.1,PR-4.2,PR-5.2,PR-2,P-6) Treatment Train 2 Removal Rate Removed Remaining Deep Sump CB 25% 0.25 0.75 Jellyfish 84% 0.63 0.12 TSS Removed= 88% Total Impervious: 49178.00 (PR-3.2) Treatment Train 3 Removal Rate Removed Remaining Rain Guardian(Pre) 0% 0 1 VDA-02 80% 0.8 0.2 TSS Removed= 80% Total Impervious: 19592.00 Adjacent developed areas Treatment Train 4 Removal Rate Removed Remaining Filter Strip(pre) 0% 0 1 Stormwater Basin 80% 0.8 0.2 TSS Removed= 80% Weighted Average= 87.90% Total Imp. 289794.00 Appendix I-Long-Term Operation and Maintenance Plan (Under Separate Cover) Stormwater Report—LWM Administration Building—492 Sutton Street Page 31 Appendix -Illicit Discharge Statement Stormwater Report—LWM Administration Building—492 Sutton Street Page 32 Illicit Discharge Compliance Statement No illicit discharges are proposed to enter the stormwater management system associated with the Lawrence Municipal Airport (LWM) Administration Building project located at 492 Sutton Street, North Andover, Massachusetts.As required under the Massachusetts Clean Waters Act(MGL c.21,§§26-53)and the Town of North Andover Stormwater Management and Erosion Control Regulations (Chapter 250), no non-stormwater discharges will be introduced into the stormwater management system. Illicit discharge detection and elimination procedures, including routine visual inspections, will be implemented in accordance with the Long-Term Operation and Maintenance Plan. certify under penalty of law that the stormwater management system as shown on the referenced plans will be operated and maintained in accordance with the Long-Term Operation and Maintenance Plan,and that no illicit discharges will be permitted to enter the stormwater management system. Responsible Party: Signature: Date: Printed Name: Title: Organization: Lawrence Municipal Airport Commission Address:492 Sutton Street, North Andover, Massachusetts 01845 Appendix K-Groundwater Mounding Analysis Stormwater Report—LWM Administration Building—492 Sutton Street Page 33 GROUNDWATER MOUNDING ANALYSIS:STORMWATER BASIN This spreadsheet will calculate the height of a groundwater mound beneath a stormwater infiltration basin. More information can be found in the U.S.Geological Survey Scientific Investigations Report 2010-5102"Simulation of groundwater mounding beneath hypothetical stormwater infiltration basins". The user must specify infiltration rate(R),specific yield(Sy),horizontal hydraulic conductivity(0), basin dimensions(x,y),duration of infiltration period(t),and the initial thickness of the saturated zone(hi(0),height of the water table if the bottom of the aquifer is the datum). For a square basin the half width equals the half length(x=y). For a rectangular basin,if the user wants the water-table changes perpendicular to the long side,specify x as the short dimension and y as the long dimension. Conversely, if the user wants the values perpendicular to the short side,specify y as the short dimension,x as the long dimension. All distances are from the center of the basin. Users can change the distances from the center of the basin at which water-table aquifer thickness are calculated. Cells highlighted in yellow are values that can be changed by the user. Cells highlighted in red are output values based on user-specified inputs. The user MUST click the blue"Re-Calculate ow"button each time ANY of the user-specified inputs are changed otherwise necessary iterations to converge on the correct solution will not be done and values shown will be incorrect. Use consistent units for all input values(for example,feet and days) use consistent units(e.g.feet&days or inches&hours) Conversion Table Input Values inch/hour feet/day 0.5400 R Recharge(infiltration)rate(feet/day) 0.67 1.33 0180 Sy Specific yield,Sy(dimensionless,between 0 and 1) 5.40 K Horizontal hydraulic conductivity,Kh (feet/day)* 2.00 4.00 In the report accompanying this spreadsheet 46.500 x 1/2 length of basin(x direction,in feet) (USGS SIR 2010-5102),vertical soil permeability 12.500 y 1/2 width of basin(y direction,in feet) hours days (ft/d)is assumed to be one-tenth horizontal 2.200 t duration of infiltration period(days) 36 1.50 hydraulic conductivity(ft/d). 27.830 hi(0) initial thickness of saturated zone(feet) h(max) maximum thickness of saturated zone(beneath center of basin at end of infiltration period) Ah(max) maximum groundwater mounding(beneath center of basin at end of infiltration period) Ground- Distance from water center of basin Mounding,in in x direction,in feet feet 0 20 40 SO 60 Groundwater Mounding, in feet 70 1.800 80 1.600 90 1.400 100 1.200 .... 120 1.000 0.800 ......................................................................................................................................................... 0.600 .................................................................................................................................................................° u. 0.400 ....................................................................................................................................................................................................................u. 0.200 0.000 .............................................................................................................................................................................................................................................................................................................................................................................................................................................. L_L_20 40 60 80 100 120 140 Disclaimer This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltration basin is made available to the general public as a convenience for those wishing to replicate values documented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneath hypothetical stormwater infiltration basins"or to calculate values based on user-specified site conditions. Any changes made to the spreadsheet(other than values identified as user-specified) after transmission from the USGS could have unintended, undesirable consequences.These consequences could include, but may not be limited to: erroneous output, numerical instabilities, and violations of underlying assumptions that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the spreadsheet. If changes are made to the spreadsheet,the user is responsible for documenting the changes and justifying the results and conclusions. GROUNDWATER MOUNDING ANALYSIS:VDA-01 This spreadsheet will calculate the height of a groundwater mound beneath a stormwater infiltration basin. More information can be found in the U.S.Geological Survey Scientific Investigations Report 2010-5102"Simulation of groundwater mounding beneath hypothetical stormwater infiltration basins". The user must specify infiltration rate(R),specific yield(Sy),horizontal hydraulic conductivity(0), basin dimensions(x,y),duration of infiltration period(t),and the initial thickness of the saturated zone(hi(0),height of the water table if the bottom of the aquifer is the datum). For a square basin the half width equals the half length(x=y). For a rectangular basin,if the user wants the water-table changes perpendicular to the long side,specify x as the short dimension and y as the long dimension. Conversely, if the user wants the values perpendicular to the short side,specify y as the short dimension,x as the long dimension. All distances are from the center of the basin. Users can change the distances from the center of the basin at which water-table aquifer thickness are calculated. Cells highlighted in yellow are values that can be changed by the user. Cells highlighted in red are output values based on user-specified inputs. The user MUST click the blue"Re-Calculate ow"button each time ANY of the user-specified inputs are changed otherwise necessary iterations to converge on the correct solution will not be done and values shown will be incorrect. Use consistent units for all input values(for example,feet and days) use consistent units(e.g.feet&days or inches&hours) Conversion Table Input Values inch/hour feet/day 0.5400 R Recharge(infiltration)rate(feet/day) 0.67 1.33 0180 Sy Specific yield,Sy(dimensionless,between 0 and 1) 5.40 K Horizontal hydraulic conductivity,Kh (feet/day)* 2.00 4.00 In the report accompanying this spreadsheet 29.000 x 1/2 length of basin(x direction,in feet) (USGS SIR 2010-5102),vertical soil permeability 17.500 y 1/2 width of basin(y direction,in feet) hours days (ft/d)is assumed to be one-tenth horizontal 1.610 t duration of infiltration period(days) 36 1.50 hydraulic conductivity(ft/d). 25.700 hi(0) initial thickness of saturated zone(feet) h(max) maximum thickness of saturated zone(beneath center of basin at end of infiltration period) Ah(max) maximum groundwater mounding(beneath center of basin at end of infiltration period) Ground- Distance from water center of basin Mounding,in in x direction,in feet feet 0 Re-Calculate Now 20 40 SO 60 Groundwater Mounding, in feet 10 1.600 80 1.400 90 1.200 100 1.000 120 0.800 ........................................................................................................... m 0.600 0.400 .......................................................................................................................................................... 0.200 ......................................................................................................................................................................................................... 0.000 ......................................................................................................................................................................................................................................................................................................................................................................... 0 20 40 60 80 100 120 140 Disclaimer This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltration basin is made available to the general public as a convenience for those wishing to replicate values documented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneath hypothetical stormwater infiltration basins"or to calculate values based on user-specified site conditions. Any changes made to the spreadsheet(other than values identified as user-specified) after transmission from the USGS could have unintended, undesirable consequences.These consequences could include, but may not be limited to: erroneous output, numerical instabilities, and violations of underlying assumptions that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the spreadsheet. If changes are made to the spreadsheet,the user is responsible for documenting the changes and justifying the results and conclusions. GROUNDWATER MOUNDING ANALYSIS:VDA-02 This spreadsheet will calculate the height of a groundwater mound beneath a stormwater infiltration basin. More information can be found in the U.S.Geological Survey Scientific Investigations Report 2010-5102"Simulation of groundwater mounding beneath hypothetical stormwater infiltration basins". The user must specify infiltration rate(R),specific yield(Sy),horizontal hydraulic conductivity(0), basin dimensions(x,y),duration of infiltration period(t),and the initial thickness of the saturated zone(hi(0),height of the water table if the bottom of the aquifer is the datum). For a square basin the half width equals the half length(x=y). For a rectangular basin,if the user wants the water-table changes perpendicular to the long side,specify x as the short dimension and y as the long dimension. Conversely, if the user wants the values perpendicular to the short side,specify y as the short dimension,x as the long dimension. All distances are from the center of the basin. Users can change the distances from the center of the basin at which water-table aquifer thickness are calculated. Cells highlighted in yellow are values that can be changed by the user. Cells highlighted in red are output values based on user-specified inputs. The user MUST click the blue"Re-Calculate ow"button each time ANY of the user-specified inputs are changed otherwise necessary iterations to converge on the correct solution will not be done and values shown will be incorrect. Use consistent units for all input values(for example,feet and days) use consistent units(e.g.feet&days or inches&hours) Conversion Table Input Values inch/hour feet/day 0.5400 R Recharge(infiltration)rate(feet/day) 0.67 1.33 0180 Sy Specific yield,Sy(dimensionless,between 0 and 1) 5.40 K Horizontal hydraulic conductivity,Kh (feet/day)* 2.00 4.00 In the report accompanying this spreadsheet 17.500 x 1/2 length of basin(x direction,in feet) (USGS SIR 2010-5102),vertical soil permeability 16.000 y 1/2 width of basin(y direction,in feet) hours days (ft/d)is assumed to be one-tenth horizontal 1.360 t duration of infiltration period(days) 36 1.50 hydraulic conductivity(ft/d). 27.310 hi(0) initial thickness of saturated zone(feet) h(max) maximum thickness of saturated zone(beneath center of basin at end of infiltration period) Ah(max) maximum groundwater mounding(beneath center of basin at end of infiltration period) Ground- Distance from water center of basin Mounding,in in x direction,in feet feet 0 �Re-Calculate Now 20 40 SO 60 Groundwater Mounding, in feet 70 1.200 80 90 1.000 100 0.800 00000'00000giipuooiii 120 0.600 0.400 u............................................................................................................................................................................................................................................................................................................................................. 0.200 ............................................................................................................... '................... 0 20 40 60 80 100 120 140 Disclaimer This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltration basin is made available to the general public as a convenience for those wishing to replicate values documented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneath hypothetical stormwater infiltration basins"or to calculate values based on user-specified site conditions. Any changes made to the spreadsheet(other than values identified as user-specified) after transmission from the USGS could have unintended, undesirable consequences.These consequences could include, but may not be limited to: erroneous output, numerical instabilities, and violations of underlying assumptions that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the spreadsheet. If changes are made to the spreadsheet,the user is responsible for documenting the changes and justifying the results and conclusions. STORMWATER CALCULATIONS MOUNDING ANALYSIS SUPPORTING DOCUMENTATION Recharge Rates(infiltration rate)in feet per day Infiltration Rate= 0.27 inches per hour Convert to Feet Per Day: _(0.27 in/hr)*(24 hr/d)*(1 ft/12inches) 0.54 feet per day Specific Yield(Sy)(porosity) (dimensionless,between 0 and 1) Per Johnson(1967)*,referenced by Westborough Conservation Commission Guidance** Sand and Gravel 0.25 Sand 0.30 Loamy Sand 0.25 Sandy Loam 0.20 Loam 0.10 Silt Loam 0.05 Silty Clay Loam 0.02 **Town of Westborough MA Conservation Department-Evaluation of Stormwater Management Mounding Analysis *USGS Water Supply Paper 1662-D(Johnson,1967)-Specific Yield-Compilation of Specific Yields for Various Materials Per MassGIS Specific Yield Data Layer at project location: Min: 0.04 Max: 0.31 Average: 0.18 Conclusion: Sandy Loam selected over Loamy Sand based on high sand content in samples Use most conservative(higher mound resulting)=0.18 Horizontal Hydraulic Conductivity(Kh,feet/day) Per guidance,USGS SIR 2010-5102,vertical soil permeability is assumed to be one tenth horizontal conductivity Per guidance,McClure multiplied the infiltration rates estimated for each BMP by a factor of 10 to derive our Kh values in the mounding analyses. Stormwater BMP Conductivity(ft/d) Kh(ft/d) BASIN 0.54 5.40 VDA-01 0.54 5.40 VDA-02 0.54 5.40 Groundwater Mounding Calculations Backup Page 1 of 2 Length and Width of Basin Stormwater BMP Length Width Half Length(x) Half Width(y) BASIN 93 25.0 46.5 12.5 VDA-01 58 35.0 29.0 17.5 VDA-02 35 1 32.0 j 17.5 j 16.0 Duration of Infiltration Period Use the following equation:Q/(A*R)=t Q=total volume to be infiltrated(recharge volume provided) A=Bottom area of infiltration practice(bottom area) R=estimated infiltration rate Stormwater BMP Q(cf)=Provided Volume A(sf)(Bottom Area) R(ft/d) t(d) BASIN 2835 2369.00 0.54 2.22 VDA-01 170 195.00 0.54 1.61 VDA-02 41 1 56.00 j 0.54 j 1.36 Initial Thickness of Saturated Zone (Height of the water table if the Bottom of the Aquifer is the Datum) Determine Depth to Bedrock. Thickness of Saturated Zone is measured from Bedrock to Top of Groundwater Thiclness of Stormwater BMP Closest Boring to Refusal Depth to Refusal Depth to GWSaturated Zone (feet) (feet) BASIN B-3 31.00 3.17 27.83 VDA-01 B-4 29.60 3.90 25.70 VDA-02 B-2 31.00 3.69 27.31 Groundwater Mounding Calculations Backup Page 2 of 2 Appendix L-Treatment Device Documentation RAIN GUARDIAN TURRET CONTECH JELLYFISH Stormwater Report—LWM Administration Building—492 Sutton Street Page 34 'A, NSEM110N 1318 McKay Drive NE, Suite 300 Ham Lake, MN 55304 www.AnokaSWCD.org �IAN www.RainGuardian.biz 93.PAW NNE,&SM A111 MAU 'PRETREATMENT FOR MORETENTION Rain Gardens*Swaim*riltrrabon Bzsnns-Ir filtrat on Basins TECHNICAL MEMORANDUM Rain Guardian Pretreatment Chambers - Functionality, Capacity, and Effectiveness December 1, 2022 To Whom It May Concern: OVERVIEW Rain Guardian pretreatment chambers were developed by Anoka Conservation District to address common inlet, pretreatment, and maintenance issues associated with stormwater BMPs. Typical inlet options for stormwater BMPs include grass filter strips and rock inlets, which are prone to erosion, require hours of maintenance, provide little or no pretreatment, and can actually cause water to bypass the practice because of their likelihood of clogging with debris. Rain Guardian pretreatment chambers provide a stable inlet to the BMP, pretreat stormwater, and simplify maintenance by capturing sediment and debris in a chamber that is quick and easy to clean. Each Rain Guardian pretreatment chamber utilizes patented functional elements (US 8,501,016, US 8,858,804, and US 11,298,635). Therefore, each chamber operates in the same manner and has a similar flow path. The four patented functional elements and a brief description of their purpose are described below. 1. The water-impermeable sidewalls form a debris and sediment trap. 2. The filter sidewall allows the chamber to drain and dry between storm events. 3. The chamber grate captures gross solids. 4. The top debris walls capture and restrict floatables from entering or exiting the BMP. FLOW PATH AND FUNCTIONALITY Rain Guardian pretreatment chambers are positioned at BMP inlets. Stormwater is most commonly directed into the chamber via a curb-cut and inlet. Water passes through the top grate, which captures gross solids. Water then enters the chamber where the settling and capture of particulates occurs. The vertical filter wall positioned on the BMP side of the chamber allows the chamber to dry out between storm events. As the BMP fills, the water level rises and the top debris walls restrict floatable debris from entering or exiting the BMP. Accumulated sediment and debris are easily removed from the chamber by removing the top grate and shoveling the interior of the chamber. The vertical filter wall can be brushed or rinsed clean. Multiple outflow points exist in each °l chamber that allow water to exit the chamber and enter the BMP during high flows. The image to the right depicts the flow path of stormwater through the Rain Guardian Turret pretreatment chamber. The flow path ' p p through the Bunker, Fortress, and Foxhole is similar. PONDING DEPTH, STORAGE CAPACITY, AND FLOW CAPACITY Each Rain Guardian pretreatment chamber is designed for a specific BMP ponding depth. Bunkers are available in 9" and 12" ponding depths, the Turret is available in a 12" ponding depth, the Fortress is available in a 9" ponding depth, and the Foxhole is available in a 9" ponding depth. The ponding depths include a 1.5" drop within the inlet (gutter or apron) to each chamber. Chamber flow capacity calculations are described in the text below and details specific to each chamber type are shown in the tables below. Inflow is possible through one location for each chamber, the chamber inlet. 1) Chamber inlet capacity- calculated using a standard broad crested weir equation (i.e. Q=C*L*HA(3/2)) Outflow is possible through three locations for each chamber. Please note the vertical filter within the chamber was assumed to be 100% clogged because its primary function is to allow the chamber to dry out between rain events. 1) Filter overflow capacity-water can pass between the top of the filter and the bottom of the grate; calculated using the continuity equation (i.e. Q=V*A) 2) Grate overflow capacity-water can pass through the top grate beyond the vertical filter wall; calculated using an orifice equation (i.e. Q=0.0108*A*�d) 3) High volume overflow capacity-water can overtop the front debris wall onto the splash pad; calculated using a standard broad crested weir equation (i.e. Q=C*L*HA(3/2)) Internal Outlet 1 - Outlet 2- Outlet 3- Total Storage Inlet Flow Filter Grate High Outlet Rain Guardian Model Capacity Rate Overflow Overflow Volume Rate (CF) (CFS) Rate(CFS) Rate(CFS) Overflow (CFS) Rate(CFS) Bunker 2.85 3.07 3.41 2.02 0.69 6.12 Turret 4.02 1.82 0.45 2.59 0.41 3.45 Fortress 1.36 4.12 3.92 2.46 1.47 7.85 Foxhole Inlet/Outlet 1.73 2.00 1.15 2.72 0.52 4.39 Combination Foxhole Middle Section 2.20 N/A N/A N/A N/A N/A Values used for each structure in flow rate calculations INLET OUTLET Rain Guardian FILTER GRATE Model C L(FT) H (FT) C L(FT) H (FT) OVERFLOW A OVERFLOW A (SF) (SF) Bunker 3.087 3.438 0.438 3.087 4.021 0.146 0.528 0.580 Tu rret 3.087 2.190 0.417 3.087 2.406 0.146 0.128 0.745 Fortress 3.087 3.344 0.542 3.087 3.380 0.271 0.406 0.621 Foxhole Inlet/Outlet 3.087 2.083 0.458 3.087 2.083 0.188 0.248 0.746 Combination 2 AK4X NORM iTr " ww.iw POLLUTANT REMOVAL EFFECTIVENESS Rain Guardian Bunkers and Turrets were independently tested by the University of Minnesota St. Anthony Falls Laboratory. Removal of TSS and gross solids is included in the "Capture of Gross Solids and Sediment by Pretreatment Practices for Bioretention, Project Report No. 586, January 2019" and the results are summarized below. • Bunker sediment capture —91.7% at 0.25 CFS and 75.6% at 0.5 CFS • Bunker qross solids capture — 78.8% at 0.25 CFS and 61.4% at 0.5 CFS • �Turret sediment�capture— 88.4% a�tO.25�CF�Sa nd�79. at 0.5 CFS • Turret gross solids capture — 86.7% at 0.25 CFS and 72.4% at 0.5 CFS The particle size distribution of sand used in testing is summarized below in the screen captures from the report. Additional details are available in the report. G era-9f"G-ross,S fi&am S - i Pre, artic as,for Biam,"tentim R .—Janmry 201.9 S ^ , r ,$ � ,a IMP on "w' �wummmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm' ,0 Ism 0-: 'N 1 "plyl I pM, 10 Porn 1011" J W I . l rn 110000I-Q, I raaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa�iuuiuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuur�uuviuiar�m�aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaonw�,�livtar�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�r�ar�,, ,,,, � ,., ,,� .,,,,.,,,,,� .,,,,„.,,,,.,„,,, .... id MIT.f. Mu"W'd, kli cagrbIuffs"di b Ohl IIIIIIIIIIYIIPi h7nonWGd, art ,, groaturi ° ., iiiiii,:IN 0 0111 �� jNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNU/Jr007 � i Il11JI��!IIIIIIIIIIIIIIIIIIIIIIIIIIIII�lfffffffffffffffffffffffffffffffffffffffffffffffffffffffffillllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllYf�ll11 t� i I 111hYrtlIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIW'Nf��11,Ytr�d�VHltI�IYYIYk��1�I��YII�lYl6'NiW�1 i ThothrGe s smwu , °, " 3 ANtKA NORM KOM 0 0 90 YV -- -- me ---- uli0�; 70 - -- -- ---- 60 u - -- --- ---- CL 000 VV ro 30 — -- AY ---- ---- CL III 1 0% — — ---- ---- r m' may' 0 0.011 0 A III 10 Particle Diameter m) Coarse (Agsoo 12 20) 111W Mlediuim (Agsco 35 50) 01 Fine (Agseo I20 200) Sethi ent imix (3 components) Figure 19.Particle size distribution chart of sand usedin,testing.Data from SAFL sieve testing. ' .rib,le 1 v ,!aria X'si of ht l , �t07 4X atilt" 'di.visioiiiI fw dKyR;,°,,N"' n c s sssa III. uie e o eniif�ni size I i Peereent IIpassing Retained 0 21.o N .o IIFe mY �� r i 6 1.17 86.2 1Yo Coarse 25 0-7 . 7_ w Come to o 0,ll. 2 1. 11 edillum 'o 0-111118 33-5% Medium o or 1,2 �,, 0l.,I 2 1 .91,! :, Fi e Pan Fine Sincerely, uy 0 it Vi r ,v r� Mitch Haustein Stormwater and Shoreland Specialist Anoka Conservation District 1318 McKay Dr. NE, Suite 300 Ham Lake, MN 55304 (763) 434-2030 ext. 150 mitch.haustein@anokaswcd.org 4 N& W A S H I N G T 0 N S T A T E DEPARTMENT OF E C O L O G Y January 2021 GENERAL USE LEVEL DESIGNATION FOR BASIC (TSS) AND PHOSPHORUS TREATMENT For Contech Environmental Solutions Jellyfish' Filter Ecology's Decision: 1. Based on Contech Environmental Solution's application submissions, Ecology hereby issues a General use level designation (GULD) for Basic (TSS) and Phosphorus Treatment for Contech's Jellyfish® Filter: • Sized at a hydraulic loading rate of no greater than 0.21 gpm/sf filter surface for hi-flo cartridges and 0.11 gpm/sf filter surface for draindown cartridges Table 1. Jellyfish® cartridge hydraulic loading rates and sediment capture capacity' associated with various filter cartridge sizes. Cartridge Design Treatment Design Sediment Mass Length Flow Rate Loading Capacity 15 inches Hi-Flo 22 gpm Hi-Flo 35 lbs Draindown 11 gpm Draindown 17 lbs 27 inches Hi-Flo 40 gpm Hi-Flo 63 lbs Draindown 20 gpm Draindown 31 lbs 40 inches Hi-Flo 60 gpm Hi-Flo 93 lbs Draindown 30 gpm Draindown 46 lbs 54 inches Hi-Flo 80 gpm Hi-Flo 125 lbs Draindown 40 gpm Draindown 63 lbs ' Design sediment mass loading capacity based on laboratory testing using silica sediment. Page 1 1 2. Ecology approves Jellyfish*'Filter units at the design treatment flow rates shown in Table 1. Total Jellyfish Filter system design treatment capacity is the sum of the design treatment capacity of individual cartridges and must equal or exceed the water quality design flow rate. Calculate the water quality design flow rate that must be treated by an individual treatment system using the following procedures: • Western Washington: For treatment installed upstream of detention or retention, the water quality design flow rate is the peak 15-minute flow rate as calculated using the latest version of the Western Washington Hydrology Model or other Ecology- approved continuous runoff model. • Eastern Washington: For treatment installed upstream of detention or retention, the water quality design flow rate is the peak 15-minute flow rate as calculated using one of the three methods described in Chapter 2.7.6 of the 2019 Stormwater Management Manual for Eastern Washington (SWMMEW) or local manual. • Entire State: For treatment installed downstream of detention, the water quality design flow rate is the full 2-year release rate of the detention facility. 3. The GULD has no expiration date but may be amended or revoked by Ecology. Ecology's Conditions of Use: Jellyfish®Filter units shall comply with the following conditions: 1. Design, assemble, install, operate, and maintain Jellyfish® Filter units in accordance with Contech's applicable manuals and documents and this Ecology Decision. 2. Contech uses sediment-loading capacity, in conjunction with the water quality design flow rate, to determine the target maintenance interval. 3. Jellyfish® Filters shall conform to specifications submitted to and approved by Ecology. 4. Maintenance: The required inspection/maintenance interval for stormwater treatment devices is often dependent on the efficiency of the device and the degree of pollutant loading from a particular drainage basin. Therefore, Ecology does not endorse or recommend a "one size fits all" maintenance cycle for a particular model/size of manufactured filter treatment device. • The Jellyfish® Filter is designed for a target maintenance interval of 12 months. Maintenance includes floatable trash, debris, and oil removal; sediment removal; and the rinsing or replacement of filter cartridges. • A Jellyfish® Filter tested in Dundee, OR averaged a 3.2 month maintenance interval. Construction activities were ongoing in the drainage basin and near the monitoring site during the first two years of the study. Monitoring personnel observed significant amounts of roadway sediments and organic debris in the runoff, and TS S concentrations were higher than typical for roadway runoff. The runoff that occurred during the study may be unusual, and the maintenance interval the Jellyfish® Filter required may not be indicative of other, more typical, sites. Page 1 2 • Owner/s operators must inspect Jellyfish® Filter systems for a minimum of twelve months from the start of post-construction operation to determine site-specific inspection/maintenance schedules and requirements. Owners/operators must conduct inspections monthly during the wet season, and every other month during the dry season. (According to the SWMMWW, the wet season in westerns Washington is October 1 to April 30. According to the SWMMEW, the wet season in eastern Washington is October 1 to June 30.) After the first year of operation, owners/operators must conduct inspections based on the findings during the first year of inspections. • Conduct inspections by qualified personnel, follow manufacturer's guidelines, and use methods capable of determining either a decrease in treated effluent flow rate and/or a decrease in pollutant removal ability. 5. Install the Jellyfish® Filter in such a manner such that flows exceeding the maximum operating rate of the system are bypassed and will not resuspend captured sediment. 6. Discharges from the Jellyfish® Filter units shall not cause or contribute to water quality standards violations in receiving waters. Applicant: CONTECH Engineered Solutions Applicant's Address: 1183 5 NE Glenn Widing Dr Portland, OR 97220 Application Documents: • Jellyfish®Filter Dundee, OR, General Use Level Designation Technical Evaluation Report, Prepared by CONTECH Engineered Solutions, December 28, 2020 • Application Letter for CULD for Jellyfish Filter - Basic Treatment, Phosphorus Treatment, and Oil Treatment, dated April 27, 2012. • Letter from Imbrium Systems dated September 4, 2012 regarding the draft CULD/PULD document. • TAPE Analysis of Jellyfish Filter OF Field Study Data, prepared by Stormwater Management Services, LLC. • TARP Field Test Performance Monitoring of a Jellyfish Filter JF4-2-1. Performance Monitoring Report for JF4-2-1 Prepared By: University of Florida, Engineering School of Sustainable Infrastructure and Environment (ESSIE), University of Florida, Gainesville, FL 32611. Final Version: 01 November 2011. • Jellyfish Filter Systems Evaluation Report in Consideration for Pilot Level Designation (PLD)for Imbrium Systems Corporation,by Gary R. Minton, PhD, PE, with Resource Planning Associates in Seattle, Washington May 7, 2008 (updated July 192008). Page 1 3 • NJCAT Technology Verification, Jellyfish Fine Sediment Filter, by the New Jersey Corporation for Advanced Technology (NJCAT) Program Imbrium Systems Corporation, June 2008 Applicant's Use Level Request: • General use level designation as a Basic (TSS) and Phosphorus Treatment device in accordance with Ecology's 2019 Stormwater Management Manual for Western Washington. Applicant's Performance Claims: Based on results from a laboratory and field-testing, the applicant claims the Jellyfish® Filter, operating at a hydraulic loading rate of no more than 0.21 gpm/sf for hi-flo cartridges and 0.11 gpm/sf for draindown cartridges, is able to remove: • 80% of total suspended solids (TSS) for influent concentrations greater than 100 mg/L and achieve a 20 mg/L effluent for influent concentrations less than 100 mg/L. • 50% of total phosphorus for influent concentrations 0.1 to 0.5 mg/L Recommendations: Ecology finds that: • Contech Engineered Solutions has shown Ecology, through laboratory and field testing, that the Jellyfish® Filter is capable of attaining Ecology's Basic (TSS) and Total Phosphorus treatment goals. Findings of Fact: Field Testing 2017-2020 Contech completed field testing in Dundee, OR on a Jellyfish® Filter unit containing six 54-inch hi-flo cartridges and one 54-inch draindown cartridge. This combination of cartridges resulted in a design flow capacity of 520 gpm (1.16 cfs). Since Contech conducted the field evaluation they contracted with Herrera Environmental Consultants to provide third party oversight. • The field evaluation was completed between March 2017 and April 2020. Throughout the evaluation a total of 23 individual storm events (18 flow-weighted composite samples and 5 peak flow grab samples) were sampled to evaluate system performance. All sampled events met the TAPE sampling event qualification criteria, while 21 of the 23 events met the influent requirements for TSS and/or total phosphorus. Peak flows during these 21 events ranged from 26% to 106% of the design treatment capacity of 520 gpm, with a mean peak flow rate of 67% of design. • Of the 23 TAPE qualified events, 21 met the requirements for TSS analysis (16 flow weighted composite; 5 peak flow grab samples). Influent concentrations ranged from 24 mg/L to 755 mg/L, with a mean concentration of 208 mg/L. Concentrations that exceeded the upper end of TAPE influent range were capped at 200 mg/L prior to calculating the pollutant removal efficiency. For all samples with influent concentrations greater than 100 mg/L the bootstrap estimate of the lower 95 percent confidence limit (LCL95) of the mean TSS reduction was 82%, meeting the 80%performance goal for Basic Treatment. The TAPE bootstrap calculator could not be used on samples with influent concentrations Page 1 4 between 20 mg/L to 100 mg/L due to the limited number of events available (n=6). For these events the mean and median effluent TSS concentrations were 19.7 and 18.1 mg/L respectively, again meeting the 20 mg/L effluent goal for Basic Treatment. • Of the 23 TAPE qualified events, 18 met the requirements for total phosphorus analysis (13 flow-weighted composite; 5 peak flow grab samples). Influent concentrations ranged from 0.211 mg/L to 1.75 mg/L, with a mean concentration of 0.535 mg/L. Concentrations that exceeded the upper end of TAPE influent range were capped at 0.5 mg/L prior to calculating the pollutant removal efficiency. The LCL 95 mean percent removal goal was 70.1%, meeting the 50%performance goal for Phosphorus Treatment. • Median particle sized distribution results from three samples showed 20% of sediment >250 µm, 31% of sediment between 62.5 to 250 µm, and 51% of sediment<62.5 µm. This demonstrates the influent to the Jellyfish consisted of primarily silt-sized particles (3.9 to 62.5 µm) and is thus representative of Pacific Northwest Stormwater. • Contech encountered several unanticipated events and challenges that disrupted the sampling and/or resulted in lost data: the Jellyfish was taken offline twice to avoid atypical sediment loading that was the result of construction within the drainage basin; monitoring was suspended to repair or replace equipment that was damaged from vandalism and extreme weather; and, a cyber-attack on Contech storage drives resulted in a loss of approximately 15% of non-sampled flow and precipitation data. Field Testing 2010-2011 Results (second-generation membrane filtration cartridges)—University of Florida (Gainesville, FL) installed and tested a Jellyfish JF4-2-1. The University conducted monitoring of the system from May 28, 2010 to June 27, 2011, with runoff from 15.01 inches of rainfall. The monitoring followed the Technology Acceptance Reciprocity Partnership (TARP) field test protocol,per the guidelines of the New Jersey Department of Environmental Projection (NJDEP). The New Jersey Corporation for Advanced Technology(NJCAT), on May 14, 2012 certified the Jellyfish Filter for 80 percent TSS removal. • The JF4-2-1 operating at a maximum treatment flow rate of 200 gpm provided a median total suspended solids (TSS) removal of 89 percent, and a median suspended sediment concentration (SSC) removal of 99 percent. Influent TSS concentrations ranged from 16.3 to 261.0 mg/L. TSS concentrations in the range of 20-100 mg/L were reduced to less than 20 mg/L for 16 of 17 events. Average TSS removal for influent TSS between 100- 200 mg/L was 90 percent. • Other median pollutant removals included: total phosphorus, 59 percent; total nitrogen, 51 percent; total copper, 90 percent; and total zinc 70 percent. • Total oil and grease influent concentrations ranged from 0.2 to 4.1 mg/L, with a median removal efficiency of 62 percent. • No maintenance was required or carried out during the 13-month monitoring period. Curves of head loss versus flow rate were nearly identical for the system with fresh cartridges (beginning of monitoring) and dirty cartridges (end of monitoring period). The sump and filter cartridges captured 166 pounds of dry basis particulate matter. Page 1 5 • Runoff treated by the JF4-2-1 was from a nearby parking lot (approximately 75 percent pavement and 25 percent planting islands). Depending on storm event intensity and wind direction, the drainage area varied from 0.12 to 0.20 acres. Laboratory Testing and Results Imbrium conducted testing at the Monteco Limited Research & Development Centre (RDC) in Mississauga, Ontario with third party testing oversight provided by Prof. James Li of Ryerson University in Toronto. The laboratory set-up used a single cartridge fitted into a tank sized to be 1/7 the volume of a full-scale 7-cartridge Jellyfish Filter system. Based on the lab test results: • A Jellyfish Filter system fitted with a single Jellyfish cartridge or multiple Jellyfish cartridges can remove greater than 86% Sil-Co-Sil 106 (mean particle size 22 microns) within a 95% confidence interval of+/- 1.3% at the system's 100% operating rate with influent sediment concentrations ranging from 100 to 300 mg/L. For systems using 12- inch diameter cartridges, each cartridge containing 91 filtration tentacles of 54-inch length, the 100% operating rate is 50 gpm per cartridge operating at 12 inches driving head (i.e., 0.66 gpm/ft2). Each (of the) 91 filtration tentacles is composed of three 18- inch long segments for a total length of 54 inches with 76 ft2 of surface area (first generation membrane filtration cartridges). • Test runs at 100 mg/L influent concentration resulted in effluent concentrations ranging from 12 to 21 mg/L. Ten of the 11 test runs had effluent less than 20 mg/L (as required for Basic Treatment). • Sampling of effluent found an average D90 of about 14 microns indicating the Jellyfish Filter System is capable of removing most particles above 15 microns. Other Jellyfish Filter Related Issues Recommended to be Addressed by the Company: 1. Conduct hydraulic testing to obtain information about maintenance requirements on a site with runoff that is more typical of the Pacific Northwest. Technology Description: Download at: http://www.conteches.com/products/stormwater- management/treatment/j ellyfish-filter Contact Information: Applicant: Jeremiah Lehman Contech Engineered Solutions, LLC. 11815 Glenn Widing Dr Portland, OR 97220 (503) 258-3136 jlehmankconteches.com Applicant website: www.conteches.com Page 1 6 Ecology web link: http://www.ecy.wa.gov/programs/wq/stormwater/newtech/index.html Ecology: Douglas C. Howie, P.E. Department of Ecology Water Quality Program (360) 407-6444 douglas.howiekecy.wa.gov Revision History Date Revision August 2008 PULD granted January 2012 PULD Extension granted September 2012 CULD for Basic treatment; PULD for Oil and Phosphorus treatment. January 2013 Modifications to format document in line with other Use Level Documents, Changes dates for QAPP, TER, and Expiration August 2014 Revised contact information and due dates for QAPP, TER, and expiration March 2015 Revised Contact Information to Contech from Imbrium November 2016 Revised Contech contact information March 2018 Revised TER delivery and Expiration dates, Changed text from Imbrium to Contech in selected locations April 2019 Revised TER delivery and Expiration dates September 2020 Revised TER delivery and Expiration dates January 2021 CULD Granted Page 1 7 6.6.2 Total Phosphorus Total phosphorus and orthophosphate phosphorous (ortho phosphorous) were analyzed for 21 of the sampled storm events. These results are shown in Tables 13 and 14. Influent EMCs for total phosphorus ranged from 0.0806 mg/L to 1.7500 mg/L with a mean of 0.4711 mg/L and a median of 0.3380 mg/L. Corresponding effluent EMCs for total phosphorus ranged from 0.030mg/L to 0.1730 mg/L with a mean of 0.0836 mg/L and a median of 0.0915 mg/L. Influent EMCs for ortho phosphorous ranged from 0.0100 mg/L to 0.0360 mg/L with a mean of 0.0179 mg/L and a median of 0.0150 mg/L. Corresponding effluent EMCs for ortho phosphorous ranged from 0.0100 mg/L to 0.0541 mg/L with a mean of 0.0192 mg/L and a median of 0.0160 mg/L. Table 13. Total Phosphorus Results Total Phosphorus Influent Method Effluent Method Individual Event ID Sample Type result reporting Influent load result reporting Effluent storm (mg/L) limit(MRL) (g) (mg/L) limit(MRL) load(g) reduction (mg/L) (mg/L) (RE)(%) 4/7/2017 Comp. 0.7060 0.0100 44.3 0.0920 0.0100 5.8 87.0 4/12/2017 Comp. 0.3380 0.0100 33.0 0.0760 0.0100 7.4 77.5 4/19/2017 Comp. 0.5000 0.0100 9.0 0.0360 0.0100 0.7 92.8 4/26/2017 Comp. 0.5040 0.0100 22.0 0.0420 0.0100 1.8 91.7 5/13/2017 Comp. 0.2560 0.0100 25.0 0.1100 0.0100 10.7 57.0 5/16/2017 Comp. 0.0940 0.0100 16.3 0.0420 0.0100 7.3 55.3 6/8/2017 Comp. 0.2560 0.0100 22.9 0.1040 0.0100 9.3 59.4 6/15/2017 Comp. 0.3620 0.0100 37.6 0.0520 0.0100 5.4 85.6 3/8/2018 Comp. 1.7500 0.0100 163.1 0.1300 0.0100 12.1 92.6 3/14/2018 Comp. 0.6520 0.0100 69.7 0.0940 0.0100 10.1 85.6 3/16/2018 Comp. 0.0820 0.0100 1.8 0.0300 0.0100 0.7 63.4 3/22/2018 Comp. 0.3640 0.0100 40.9 0.0720 0.0100 8.1 80.2 3/27/2019 Comp. 0.2260 0.0500 39.5 0.0699 0.0500 12.2 69.1 4/5/2019 Pea k 0.3370 0.0500 1.7 0.0915 0.0500 0.5 72.8 4/13/2019 Pea k 0.2490 0.0500 95.9 0.0870 0.0500 33.5 65.1 5/18/2019 Pea k 1.0900 0.2500 122.7 0.1730 0.0500 19.5 84.1 12/7/2019 Comp. 0.3350 0.0500 89.9 0.1050 0.0500 28.2 68.7 12/11/2019 Comp. 0.0806 0.0500 8.5 0.0523 0.0500 5.5 35.1 12/19/2019 Comp. 0.2110 0.0500 37.1 0.0925 0.0500 16.2 56.2 3/30/2020 Pea k 1.0500 0.0500 126.0 0.0921 0.0500 11.1 91.2 4/20/2020 Pea k 0.4510 0.0500 27.9 0.1120 0.0500 6.9 75.2 Min 0.0806 0.0100 1.7 0.0300 0.0100 0.5 35.1 Max 1.7500 0.2500 163.1 0.1730 0.0500 33.5 92.8 Mean 0.4711 0.0367 49.3 0.0836 0.0271 10.1 73.6 Median 0.3380 0.0100 37.1 0.0915 0.0100 8.1 75.2 Sum 1034.9 213.0 42 Table 21. Basic Treatment TSS results Total Suspended Solids(TSS) Method Method Basic Criteria 1 Influent Effluent Basic Criteria 2 reporting Influent reporting Effluent 20-100 mg/I Event ID Sample Type result result 100-200 mg/I limit(MRL) load(kg) limit(MRL) load(kg) Eff.conc. (mg/L) (mg/L) (mg/L) (mg/L) <_20mg/l >_80%RE(%)a 3/20/2017 Comp. 51.2 2.0 6.8 19.4 2.1 2.6 19.4 3/21/2017 Comp. 102.0 2.0 7.1 22.0 2.0 1.5 78.4 4/7/2017 Comp. 201.0 2.0 12.6 30.8 2.0 1.9 84.6 4/12/2017 Comp. 108.0 2.0 10.6 24.4 2.0 2.4 77.4 4/19/2017 Comp. 452.0 2.0 8.2 44.6 2.1 0.8 77.7 4/26/2017 Comp. 257.0 2.3 11.2 10.0 2.4 0.4 95.0 5/13/2017 Comp. 66.0 2.0 6.4 33.2 2.0 3.2 33.2 5/16/2017 Comp. 24.0 2.0 4.2 6.8 2.0 1.2 6.8 6/8/2017 Comp. 73.6 2.0 6.6 16.8 2.0 1.5 16.8 6/15/2017 Comp. 134.0 2.5 13.9 10.4 2.0 1.1 92.2 3/8/2018 Comp. 755.0 3.3 70.4 47.2 2.0 4.4 76.4 3/14/2018 Comp. 181.0 5.0 19.4 27.0 5.0 2.9 85.1 3/16/2018 Comp. 19.0 5.0 0.4 N D 5.0 0.1 3/22/2018 Comp. 224.0 5.0 25.1 20.0 5.0 2.2 90.0 3/27/2019 Comp. 94.0 5.0 16.4 11.0 5.0 1.9 11.0 4/5/2019 Peak 171.0 5.0 0.9 23.0 5.0 0.1 86.5 4/13/2019 Peak 117.0 5.0 45.0 25.0 5.0 9.6 78.6 5/18/2019 Peak 254.0 5.0 28.6 20.0 5.0 2.3 90.0 12/7/2019 Comp. 200.0 5.0 53.7 17.0 5.0 4.6 91.5 12/11/2019 Comp. 13.0 5.0 1.4 10.0 5.0 1.1 12/19/2019 Comp. 91.0 5.0 16.0 31.0 5.0 5.4 31.0 3/30/2020 Peak 605.0 5.0 72.6 51.0 5.0 6.1 74.5 4/20/2020 Peak 210.0 5.0 13.0 29.0 5.0 1.8 85.5 Min 13.0 2.0 0.4 5.0 2.0 0.1 6.8 74.5 Max 755.0 5.0 72.6 51.0 5.0 9.6 33.2 95.0 Mean 191.4 3.7 19.6 23.2 3.6 2.6 19.7 84.2 Median 134.0 5.0 12.6 22.0 5.0 1.9 18.1 85.1 Lower 95%for RE b 82.0 Sum 450.4 59.2 a Influent TSS concentrations capped at 200 mg/L for Basic Criteria 2 RE calculation purposes b confidence interval calculated using TAPE bootstrap confidence interval calculator 53 Table 16. Total Zinc and Total Copper Results Total Zn Total Cu Method Method Individual Method Method Individual Influent reporting Influent Effluent reporting Effluent storm Influent reporting Influent Effluent reporting Effluent storm Event ID Sample Type result limit(MRL) load(g) result limit(MRL) load(g) reduction result limit(MRL) load(g) result limit(MRL) load(g) reduction (mg/L) (mg/L) (mg/L) (mg/L) (RE)(%) (mg/L) (mg/L) (mg/L) (mg/L) (RE)(%) 4/7/2017 Comp. 0.1450 0.0020 9.1 0.0399 0.0020 2.5 72.5 0.0258 0.0005 1.62 0.0085 0.0005 0.54 66.9 4/12/2017 Comp. 0.0797 0.0020 7.8 0.0317 0.0020 3.1 60.2 0.0126 0.0010 1.23 0.0032 0.0010 0.32 74.3 4/19/2017 Comp. 0.1460 0.0020 2.6 0.0209 0.0020 0.4 85.7 0.0248 0.0005 0.45 0.0032 0.0005 0.06 87.2 4/26/2017 Comp. 0.0875 0.0020 3.8 0.0166 0.0020 0.7 81.0 0.0160 0.0005 0.70 0.0019 0.0005 0.08 87.9 5/13/2017 Comp. 0.0637 0.0020 6.2 0.0423 0.0020 4.1 33.6 0.0109 0.0005 1.06 0.0073 0.0005 0.71 33.4 5/16/2017 Comp. 0.0381 0.0020 6.6 0.0244 0.0020 4.2 36.0 0.0060 0.0005 1.04 0.0036 0.0005 0.62 40.3 6/8/2017 Comp. 1.8900 0.0020 168.9 1.2400 0.0020 110.8 34.4 0.0164 0.0005 1.47 0.0071 0.0005 0.63 57.0 6/15/2017 Comp. 0.2220 0.0020 23.1 0.1040 0.0020 10.8 53.2 0.0230 0.0005 2.39 0.0070 0.0005 0.72 69.7 3/8/2018 Comp. 0.3740 0.0020 34.9 0.0518 0.0020 4.8 86.1 0.0597 0.0005 5.56 0.0172 0.0005 1.60 71.2 3/14/2018 Comp. 0.1300 0.0020 13.9 0.0412 0.0020 4.4 68.3 0.0225 0.0005 2.41 0.0058 0.0005 0.62 74.3 3/16/2018 Comp. 0.0444 0.0020 1.0 0.0282 0.0020 0.6 36.5 0.0180 0.0005 0.40 0.0023 0.0005 0.05 87.1 3/22/2018 Comp. 0.1170 0.0020 13.1 0.0305 0.0020 3.4 73.9 0.1360 0.0005 15.27 0.0040 0.0005 0.45 97.0 3/27/2019 Comp. 0.0675 0.0020 11.8 0.0345 0.0020 6.0 48.9 0.0133 0.0005 2.33 0.0047 0.0005 0.82 64.7 4/5/2019 Peak 0.1100 0.0020 0.5 0.0313 0.0020 0.2 71.5 0.0196 0.0005 0.10 0.0065 0.0005 0.03 66.8 4/13/2019 Pea k 0.0826 0.0020 31.8 0.0366 0.0020 14.1 55.7 0.0182 0.0005 7.01 0.0098 0.0005 3.77 46.2 5/18/2019 Pea k 0.4560 0.0020 51.3 0.0356 0.0020 4.0 92.2 0.0601 0.0005 6.76 0.0068 0.0005 0.76 88.7 12/7/2019 Comp. 0.1990 0.0020 53.4 0.0815 0.0020 21.9 59.0 0.0167 0.0005 4.48 0.0055 0.0005 1.48 66.9 12/11/2019 Comp. 0.0959 0.0020 10.2 0.0805 0.0020 8.5 16.1 0.0081 0.0005 0.85 0.0070 0.0005 0.74 13.6 12/19/2019 Comp. 0.1500 0.0020 26.3 0.0697 0.0020 12.2 53.5 0.0125 0.0005 2.20 0.0064 0.0005 1.13 48.7 3/30/2020 Pea k 0.4050 0.0020 48.6 0.0432 0.0020 5.2 89.3 0.0625 0.0010 7.50 0.0109 0.0010 1.31 82.6 4/20/2020 Pea k 0.1310 0.0020 8.1 0.0372 0.0020 2.3 71.6 0.0315 0.0010 1.95 0.0154 0.0010 0.95 51.1 Min 0.0381 0.0020 0.5 0.0166 0.0020 0.2 16.1 0.0060 0.0005 0.10 0.0019 0.0005 0.03 13.6 Max 1.8900 0.0020 168.9 1.2400 0.0020 110.8 92.2 0.1360 0.0010 15.27 0.0172 0.0010 3.77 97.0 Mean 0.2397 0.0020 25.4 0.1010 0.0020 10.7 60.9 0.0292 0.0006 3.18 0.0069 0.0006 0.83 65.5 Median 0.1300 0.0020 11.8 0.0372 0.0020 4.2 60.2 0.0182 0.0005 1.95 0.0065 0.0005 0.71 66.9 Sum 533.2 224.4 66.77 17.41 46 C!5 4wi-� ENGINEERED SOLUTIONS A QUIKRETV COMPANY Jelly fish° Filter Owner's Manual ................................................................................................ .......... ........................................................................ ................................................................................. .......... "I'll"............. 111111111111111"MIN WN uuuuuulllllll �� ,.../r fYD f�� ,�,,, �,,.ruiirrtrru� rrr��;-�;;,,�,,, ��/ jji/%�'��", .......... //. // / / Ed! .......... 1 / J 1 , / f ulllllll III, rr // / III I, Ildl II r / rov / J ,r r / . r r Filter Table of Contents Chapter 1 1.0 Owner Specific Jellyfish Product Information...............................................................................4 Chapter 2 2.0 Jellyfish Filter System Operations & Functions .............................................................................5 2.1 Components & Cartridges..........................................................................................................6 2.2 Jellyfish Membrane Filtration Cartridges Assembly......................................................................7 2.3 Installation of Jellyfish Membrane Filtration Cartridges................................................................7 Chapter 3 3.0 Inspection and Maintenance Overview.......................................................................................8 Chapter 4 4.0 Inspection Timing ......................................................................................................................8 Chapter 5 5.0 Inspection Procedure..................................................................................................................8 5.1 Dry Weather Inspections ............................................................................................................8 5.1 Wet Weather Inspections...........................................................................................................9 Chapter 6 6.0 Maintenance Requirements........................................................................................................9 Chapter 7 7.0 Maintenance Procedure .............................................................................................................9 7.1 Filter Cartridge Removal .............................................................................................................9 7.2 Filter Cartridge Rinsing ...............................................................................................................9 7.3 Sediment and Flotables Extraction............................................................................................ 10 7.4 Filter Cartridge Reinstallation and Replacement......................................................................... 10 7.5 Chemical Spills......................................................................................................................... 10 5.6 Material Disposal ..................................................................................................................... 10 Jellyfish Filter Inspection and Maintenance Log......................................................................................................... 12 THANK YOU FOR PURCHASING THE JELLYFISH° FILTER! Contech Engineered Solutions would like to thank you for selecting the Jellyfish Filter to meet your project's stormwater treatment needs. With proper inspection and maintenance, the Jellyfish Filter is designed to deliver ongoing, high levels of stormwater pollutant removal. If you have any questions, please feel free to call us or e-mail us: Contech Engineered Solutions 9025 Centre Pointe Drive, Suite 400 1 West Chester, OH 45069 513-645-7000 1 800-338-1122 www.ContechES.com info@conteches.com 2 Jellyfish° Filter Owner's Manual FRAME AND COVER TOP SLAB— DRAINDOWN CARTRIDGE(S) H I-FLO CARTRIDGE(S) (SMALLER ORIFICE) (LARGE ORIFICE)" f f (I lJ MAINTENANCE ACCESS WALL(MAW) (MANHOLE ONLY) ACCESS STEPS u��nmuaililili�iltllllN(IliiBfiflfuup�l��i °�Im /u�glilh9�uuumuumuuu°muuViimuuumViuuu I� I � Iv�lvvv v vv v vv v vvvv vv v vvvv vvv nv r, i f ADDITIONAL RISER SECTION (IF NEEDED) P pIIIIIum�ulullllpml�,i u OUTLET PIPE (GROUTED IN OR BOOTED), CARTRIDGE RECEPTACLES w DECK ASSEMBLY BACKWASH POOL WEIR e 1 °I CONTROL SECTION " (WITH JELLYFISH DECK) ---,INLET PIPE (GROUTED IN OR BOOTED) GASKET m (AT EACH JOINT) SEPARATOR SKIRT__.,e// (MANHOLE ONLY) �,m BASE SECTION Jellyfish° Filter Owner's Manual 3 WARNINGS/CAUTION 1. FALL PROTECTION may be required. Confined Space Entry 2. WATCH YOUR STEP if standing on the Jellyfish Filter Deck at Secure all equipment and perform all training to meet applicable any time; Great care and safety must be taken while walking local and OSHA regulations regarding confined space entry. It is the or maneuvering on the Jellyfish Filter Deck. Attentive care Contractor's or entry personnel's responsibility to proceed safely at must be taken while standing on the Jellyfish Filter Deck at all times. all times to prevent stepping onto a lid, into or through a cartridge hole or slipping on the deck. 3. The Jellyfish Filter Deck can be SLIPPERY WHEN WET. Personal Safety Equipment 4. If the Top Slab, Covers or Hatches have not yet been installed, Contractor is responsible to provide and wear appropriate personal or are removed for any reason, great care must be taken to protection equipment as needed including, but not limited to safety NOT DROP ANYTHING ONTO THE JELLYFISH FILTER DECK. The boots, hard hat, reflective vest, protective eyewear, gloves and fall Jellyfish Filter Deck and Cartridge Receptacle Rings can be protection equipment as necessary. Make sure all equipment is damaged under high impact loads.This type of activity voids staffed with trained and/or certified personnel, and all equipment is all warranties. All damaged items to be replaced at owner's checked for proper operation and safety features prior to use. expense. Fall protection equipment 5. Maximum deck load 2 persons, total weight 450 lbs. Eye protection • Safety boots • Ear protection Safety Notice Gloves •Jobsite safety is a topic and practice addressed comprehensively by Ventilation and respiratory protectionHard hat others. The inclusions here are intended to be reminders to whole Maintenance and protection of traffic plan areas of Safety Practice that are the responsibility of the Owner(s), Manager(s) and Contractor(s). OSHA and Canadian OSH, and Federal, State/Provincial, and Local Jurisdiction Safety Standards apply on any given site or project. The knowledge and applicability of those responsibilities is the Contractor's responsibility and outside the scope of Contech Engineered Solutions. Chapter 1 1.0—Owner Specific Jellyfish Filter Product Information Below you will find a reference page that can be filled out according to your Jellyfish Filter specification to help you easily inspect, maintain and order parts for your system. Owner Name: Phone Number: Site Address: Site GPS Coordinates/unit location: Unit Location Description: Jellyfish Filter Model No.: Contech Project&Sequence Number No. of Hi-Flo Cartridges No. of Cartridges: Length of Draindown Cartridges: No. of Blank Cartridge Lids: Bypass Configuration (Online/Offline): Notes: 4 Jellyfish° Filter Owner's Manual Chapter 2 2.0—Jellyfish Filter System Operations and Functions The Jellyfish Filter is an engineered stormwater quality treatment technology that removes a high level and wide variety of stormwater pollutants. Each Jellyfish Filter cartridge consists of eleven membrane- encased filter elements ("filtration tentacles") attached to a cartridge head plate. The filtration tentacles provide a large filtration surface area, resulting in high flow and high pollutant removal capacity. The Jellyfish Filter functions are depicted in Figure 1 below. FIGURE 1 Jellyfish Filter Treatment Functions Membrane Filtration Section View with Maintenance Access Wall (MAW) Cutaway Effluent Pipe Influent Pipe 1h,A Ij ��\\\\\\\\\��p�� III �� IIIIIIIIIIIIIIIIIIIIIIIII i Floatables �� Filtered Water Muuu�NGaiOOR nia hhouo oa�ouo oa�oam vur�o�o�0111HIN0110H�o�0110Ho�o�01001110210 y Collection j Particles Filtered i p6\U0�6\U1a�\\1�� Particles Settling t Jellyfish Filter cartridges are backwashed after each peak storm event, which removes accumulated sediment from the membranes. This backwash process extends the service life of the cartridges and increases the time between maintenance events. For additional details on the operation and pollutant capabilities of the Jellyfish Filter please refer to additional details on our website at www.ContechES.com. Jellyfish° Filter Owner's Manual 5 2.1 — Components and Cartridges The Jellyfish Filter and components are depicted in Figure 2 below. FIGURE 2 Jellyfish Filter Components Equipment Access Personnel Access Manhole Structure Outlet Pipe Inlet Pipe aEau :�� I IIIIIIIIIIIII�I( �j�� Ili i�pi°�°� Hi-Flo Cartridges with Lid 1, // Maintenance Access Wall � ��/ ,; (inside backwash pool) (MAW) frft fr �� Draindown Cartridge with Lid 1, i g � Backwash Pool Weir (outside of backwash pool) e �� Cartridge Deck Membrane Filtration Tentacles f f Sediment III O111�1�11111�11 ii Note: Separator Skirt not shown Tentacles are available in various lengths as depicted in Table 1 below. Table 1 —Cartridge Lengths/Weights and Cartridge Lid Orifice Diameters Cartridge Lengths Dry Weight Hi-Flo Orifice Draindown Orifice Diameter Diameter 15 inches(381 mm) 10 Ibs(4.5 kg) 35 mm 20 mm 27 inches(686 mm) 14.5 Ibs(6.6 kg) 45 mm 25 mm 40 inches (1,016 mm) 19.5 Ibs (8.9 kg) 55 mm 30 mm 54 inches (1,372 mm) 25 Ibs(11.4 kg) 70 mm 35 mm 6 Jellyfish° Filter Owner's Manual 2.2 —Jellyfish Membrane Filtration Cartridge Assembly The Jellyfish Filter utilizes multiple membrane filtration cartridges. Each cartridge consists of removable cylindrical filtration "tentacles" attached to a cartridge head plate. Each filtration tentacle has a threaded pipe nipple and o-ring. To attach, insert the top pipe nipples with the o-ring through the head plate holes and secure with locking nuts. Hex nuts to be hand tightened and checked with a wrench as shown below. 2.3 —Jellyfish Membrane Filtration Cartridge Installation • Cartridge installation will be performed by trained individuals and coordinated with the installing site Contractor. Flow r diversion devices are required to be in place until the site is �� ;�� stabilized final paving and landscaping in place). Failure to ( p g p g p ) address this step completely will reduce the time between required maintenance. • Descend to the cartridge deck(see Safety Notice and page 3) • Refer to Contech s submittal drawings to determine proper quantity and placement of Hi-Flo, Draindown and Blank 0 cartridges with appropriate lids. Lower the Jellyfish membrane filtration cartridges into the cartridge receptacles within they cartridge deck. It is possible that not all cartridge receptacles will be filled with a filter cartridge. In that case, a blank headplate and blank cartridge lid (no orifice) would be Cartridge Assembly installed. Do not force the tentacles down into the cartridge receptacle, as this may damage the membranes. Apply downward pressure on the cartridge head plate to seat the lubricated rim gasket (thick circular gasket surrounding the circumference of the head plate) into the cartridge receptacle. (See Figure 3 for details on approved lubricants for use with rim gasket.) • Examine the cartridge lids to differentiate lids with a small orifice, a large orifice, and no orifice. • Lids with a small orifice are to be inserted into the Draindown cartridge receptacles, outside of the backwash pool weir. • Lids with a large orifice are to be inserted into the Hi-Flo cartridge receptacles within the backwash pool weir. • Lids with no orifice (blank cartridge lids) and a blank headplate are to be inserted into unoccupied cartridge receptacles. • To install a cartridge lid, align both cartridge lid male threads with the cartridge receptacle female threads before rotating approximately 1/3 of a full rotation until firmly seated. Use of an approved rim gasket lubricant may facilitate installation. Jellyfish° Filter Owner's Manual 7 3.0 Inspection and Maintenance Overview 1. A minimum of quarterly inspections during the first year of The primary purpose of the Jellyfish® Filter is to capture and remove operation to assess the sediment and floatable pollutant pollutants from stormwater runoff. As with any filtration system, accumulation, and to ensure proper functioning of the system. these pollutants must be removed to maintain the filter's maximum 2. Inspection frequency in subsequent years is based on the treatment performance. Regular inspection and maintenance are inspection and maintenance plan developed in the first year of required to insure proper functioning of the system. operation. Minimum frequency should be once per year. Maintenance frequencies and requirements are site specific and vary . 3. Inspection is recommended after each major storm event. depending on pollutant loading.Additional maintenance activities may be required in the event of non-storm event runoff, such as 4. Inspection is required immediately after an upstream oil,fuel or base-flow or seasonal flow, an upstream chemical spill or due to other chemical spill. excessive sediment loading from site erosion or extreme runoff events. It is a good practice to inspect the system after major storm 5.0 Inspection Procedure events. The following procedure is recommended when performing Inspection activities are typically conducted from surface inspections: observations and include: 1. Provide traffic control measures as necessary. Observe if standing water is present Observe if there is any physical damage to the deck or 2. Inspect the MAW or inlet bay for floatable pollutants such as trash, debris, and oil sheen. cartridge lids Observe the amount of debris in the Maintenance 3. Measure oil and sediment depth in several locations, by Access Wall (MAW) or inlet bay for vault systems lowering a sediment probe until contact is made with the floor Maintenance activities include: of the structure. Record sediment depth, and presences of any • oil layers. Removal of oil, floatable trash and debris • Removal of collected sediments 4. Inspect cartridge lids. Missing or damaged cartridge lids to be • Rinsing and re-installing the filter cartridges replaced. • Replace filter cartridge tentacles, as needed 5. Inspect the MAW(where appropriate), cartridge deck and receptacles, and backwash pool weir,for damaged or broken 4.0 Inspection Timing components. Inspection of the Jellyfish Filter is key in determining the maintenance 5.1 Dry weather inspections requirements for, and to develop a history of, the site's pollutant Inspect the cartridge deck for standing water, and/or loading characteristics. In general, inspections should be performed sediment on the deck. at the times indicated below;or per the approved project No standing water under normal operating conditions. stormwater quality documents(if applicable), whichever is more Standing water inside the backwash pool, but not frequent. outside the backwash pool indicates, that the filter cartridges need to be rinsed. ,duwa Personnel " Equipment - Access � Access , Manhole Structure e. it f�l�i{Ir�l��ll� I i il Outlet Pipe p Inlet Pipe u,AHuHuHuuHuHuHuuHuHuHuu Hi-Flo Cartridges Maintenance W,..,,�.....,U.,, with Lid Access WaIIl+�rrruu�r backwash pool) Downdrain Cartridge � . a�m�mA„„o�,u��o�m�iaa�`�ai��n�`�ain`oin`oiNai?ti!,u,iuiou with Lid(outside of �`' �� %%/' lmn �� jl��l�lfl�� B a c kwa s h � backwash pool) l�� Pool Weir Membrane ' \a\wimmmmmmmmmmmmmmmmmmNNeeaa,mofiujt\r�s�% / Cartridge Deck Filtration Tentacles 12 f J„�r,�//% 1 1: , Sediment/ ` m,n!�iu��cmamriuifl�cnmm��w�iuiNcaowaiuiNcaowaiuiNca.sm,iuiNcmiuo / o Inspection Utilizing Sediment Probe Note:Separator Skirt not shown 8 Jellyfish° Filter Owner's Manual • Standing water outside the backwash pool is not anticipated and may indicate a backwater condition 4. To access the cartridge deck for filter cartridge service, descend caused by high water elevation in the receiving into the structure and step directly onto the deck. Caution: Do water body, or possibly a blockage in downstream not step onto the maintenance access wall (MAW) or backwash • infrastructure. pool weir, as damage may result. Note that the cartridge deck Any appreciable sediment (>_1/16 ) accumulated on the may be slippery. deck surface should be removed. 5. Maximum weight of maintenance crew and equipment on the 5.2 Wet weather inspections cartridge deck not to exceed 450 lbs. Observe the rate and movement of water in the unit. Note the depth of water above deck elevation within the 7.1 Filter Cartridge Removal MAW or inlet bay. 1. Remove a cartridge lid. Less than 6 inches, flow should be exiting the cartridge . lids of each of the draindown cartridges (i.e. cartridges 2. Remove cartridges from the deck using the lifting loops in the located outside the backwash pool). cartridge head plate. Rope or a lifting device(available from 9 Greater than 6 inches, flow should be exiting the Contech) should be used. Caution:Should a snag occur, do cartridge lids of each of the draindown cartridges and not force the cartridge upward as damage to the tentacles may each of the hi-flo cartridges (i.e. cartridges located result. Wet cartridges typically weigh between 100 and 125 lbs. inside the backwash pool), and water should be 3. Replace and secure the cartridge lid on the exposed empty overflowing the backwash pool weir. receptacle as a safety precaution. Contech does not recommend 21 inches or greater and relatively little flow is exiting exposing more than one empty cartridge receptacle at a time. the cartridge lids and outlet pipe, this condition indicates that the filter cartridges need to be rinsed. 7.2 Filter Cartridge Rinsing 1. Remove all 11 tentacles from the cartridge head plate. Take 6.0 Maintenance Requirements care not to lose or damage the 0-ring seal as well as the plastic Required maintenance for the Jellyfish Filter is based upon results threaded nut and connector. of the most recent inspection, historical maintenance records, or r the site specific water quality management plan; whichever is more frequent. In general, maintenance requires some combination of the following. 1. Sediment removal for depths reaching 12 inches or greater, or 71 within 3 years of the most recent sediment cleaning,whichever occurs sooner. �� 2. Floatable trash, debris, and oil removal. 3. Deck cleaned and free from sediment. 4. Filter cartridges rinsed and re-installed as required by the most recent inspection results, or within 12 months of the most recent filter rinsing, whichever occurs sooner. 5. Replace tentacles if rinsing does not restore adequate hydraulic capacity, remove accumulated sediment, or if damaged or missing. It is recommended that tentacles should remain inr service no longer than 5 years before replacement. 6. Damaged or missing cartridge deck components must be repaired or replaced as indicated by results of the most recent inspection. 7. The unit must be cleaned out and filter cartridges inspected Cartridge Removal&Lifting Device immediately after an upstream oil, fuel, or chemical spill. Filter cartridge tentacles should be replaced if damaged or compromised by the spill. 2. Position tentacles in a container(or over the MAW), with the 7.0 Maintenance Procedure threaded connector(open end)facing down, so rinse water is flushed throu h the membrane and captured in the container. The following procedures are recommended when maintaining the g p Jellyfish Filter: 3. Using the Jellyfish rinse tool (available from Contech) or a 1. Provide traffic control measures as necessary. low-pressure garden hose sprayer, direct water spray onto the tentacle membrane, sweeping from top to bottom along the 2. Open all covers and hatches. Use ventilation equipment as length of the tentacle. Rinse until all sediment is removed from required, according to confined space entry procedures. the membrane. Caution: Do not use a high pressure sprayer Caution. Dropping objects onto the cartridge deck may cause or focused stream of water on the membrane. Excessive water damage. pressure may damage the membrane. 3. Perform Inspection Procedure prior to maintenance activity. Jellyfish° Filter Owner's Manual 9 4. Collected rinse water is typically removed by vacuum hose. 7.4 Filter Cartridge Reinstallation and Replacement 5. Reassemble cartridges as detailed later in this document. Reuse 1. Cartridges should be installed after the deck has been cleaned. 0-rings and nuts, ensuring proper placement on each tentacle. It is important that the receptacle surfaces be free from grit and debris. 7.3 Sediment and Flotables Extraction 2. Remove cartridge lid from deck and carefully lower the filter 1. Perform vacuum cleaning of the Jellyfish Filter only after cartridge into the receptacle until head plate gasket is seated filter cartridges have been removed from the system. Access squarely in receptacle. Caution. Do not force the cartridge the lower chamber for vacuum cleaning only through the downward; damage may occur maintenance access wall (MAW) opening. Be careful not to damage the flexible plastic separator skirt that is attached to 3. Replace the cartridge lid and check to see that both male the underside of the deck on manhole systems. Do not lower threads are properly seated before rotating approximately 1/3 the vacuum wand through a cartridge receptacle, as damage to of a full rotation until firmly seated. Use of an approved rim the receptacle will result. gasket lubricant may facilitate installation. See next page for additional details. 2. Vacuum floatable trash, debris, and oil, from the MAW . opening or inlet bay. Alternatively, floatable solids may be 4. If rinsing is ineffective in removing sediment from the tentacles, removed by a net or skimmer. or if tentacles are damaged, provisions must be made to replace the spent or damaged tentacles with new tentacles. Contact Contech to order replacement tentacles. o" 7.5 Chemical Spills � rr„ Caution: If a chemical spill has been captured, do not attempt maintenance. Immediately contact the local hazard response agency and contact Contech. 7.6 Material Disposal The accumulated sediment found in stormwater treatment and conveyance systems must be handled and disposed of in accordance with regulatory protocols. It is possible for sediments to contain measurable concentrations of heavy metals and organic chemicals (such as pesticides and petroleum products).Areas with the greatest potential for high pollutant loading include industrial areas and heavily traveled roads. Sediments and water must be disposed r� of in accordance with all applicable waste disposal p regulations.p p Rinsing Cartridge with Contech Rinse Tool When scheduling maintenance, consideration must be made for the disposal of solid and liquid wastes.This typically requires 3. Pressure wash cartridge deck and receptacles to remove all coordination with a local landfill for solid waste disposal. For sediment and debris. Sediment should be rinsed into the sump liquid waste disposal a number of options are available including a area. Take care not to flush rinse water into the outlet pipe. municipal vacuum truck decant facility, local waste water treatment 4. Remove water from the sump area.Vacuum or pump plant or on-site treatment and discharge. equipment should only be introduced through the MAW or inlet bay. 5. Remove the sediment from the bottom of the unit through the MAW or inlet bay opening. I'' 'I;IIII'II�1I�iItlU��l II'��il � p� r m r; Vacuuming Sump Through MAW 6. For larger diameter Jellyfish Filter manholes(>_8-ft) and some vaults complete sediment removal may be facilitated by removing a cartridge lid from an empty receptacle and inserting a jetting wand (not a vacuum wand)through the receptacle. Use the sprayer to rinse loosened sediment toward the vacuum hose in the MAW opening, being careful not to damage the receptacle. 10 Jellyfish° Filter Owner's Manual Jellyfish Filter Components & Filter Cartridge Assembly and Installation '111111 l� n i 6 CARTRIDGE LID:ORIFICE DIAMETER PER PROJECT l ",, ( DRAWING 9 w d rv" ,w O—RING:INSTALLED WITH EACH MEMBRANE r j FILTRATION TENTACLE (DI r a CARTRIDGE RECEPTACLE: SECURED TO CARTRIDGE DECK ENSURE EYE BOLTS ARE ALIGNED TO FACILITATE LIFTING DEVICE 5 1 ` 4 / �,,, SEE NOTE FOR J LUBRICATION DETAILS 8 SCREW,BUTTON HEAD CAP REQUIRES 5MM HEX WRENCH TABLE 1:BOM ITEM NO. DESCRIPTION NOTES: 1 JF HEAD PLATE Head Plate Gasket Installation: 2 JF TENTACLE Install Head Plate Gasket(Item 4)onto the Head Plate(Item 1) 3 JF O-RING and liberally apply a lubricant from Table 2:Approved Gasket JF HEAD PLATE Lubricants onto the gasket where it contacts the Receptacle 4 GASKET (Item 7)and Cartridge Lid(Item 6).Follow Lubricant 5 JF CARTRIDGE EYELET 6 JF 141N COVER manufacturer's instructions. 7 JF RECEPTACLE BUTTON HEAD CAP Lid Assembly: 8 SCREW M6X14MM SS Rotate Cartridge Lid counter-clockwise until both male threads 9 JF CARTRIDGE NUT drop down and properly seat.Then rotate Cartridge Lid clock-wise approximately one-third of a full rotation until TABLE 2:APPROVED GASKET LUBRICANTS Cartridge Lid is firmly secured,creating a watertight seal. PART NO. MFR DESCRIPTION 78713 LA-CO LUBRI-JOINT 40501 HERCULES DUCK BUTTER 30600 OATEY PIPE LUBRICANT PSLUBXL1Q I PROSELECT I PIPE JOINT LUBRICANT Jellyfish° Filter Owner's Manual 1 1 Jellyfish Filter Inspection and Maintenance Log Owner: Jellyfish Model No.: Location: GPS Coordinates: Land Use: Commercial: Industrial: Service Station: Road/Highway: Airport: Residential: Parking Lot: Date/Time: nspector: Maintenance Contractor: Visible Oil Present: (Y/N) Oil Quantity Removed Floatable Debris Present: (Y/N) Floatable Debris removed: (Y/N) Water Depth in Backwash Pool Cartridges externally rinsed/re-commissioned: (Y/N) New tentacles put on Cartridges: (Y/N) Sediment Depth Measured: (Y/N) Sediment Depth (inches or mm)- Sediment Removed: (Y/N) Cartridge Lids intact: (Y/N) Observed Damage: Comments: 12 Jellyfish° Filter Owner's Manual CES JF OM 10/2025