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Stormwater Report - 1018 OSGOOD STREET 3/25/2013
S'TORMWA TER MANAGEMENT REPORT Map 35 Lot 19 1018 Osgood Street North Andover, MA 01845 Prepared For: JFJ Holdings, LLC 751 Main Street, Suite B Sanford, ME 04073 October 19, 2012 Revised: December 7, 2012 Revised: January 28, 2013 Revised: March 1, 2013 Revised: March 25, 2013 m ti 21 i � a .. _ X, r ` Am MHF Design consultants, Inc. ENGINEERS - PLANNERS - SURVEYORS 44 Stiles Road ® Suite One - Salem, NH 03079 TEL (603) 393-0720 - FAX (603) 393-0733 www.mhfdesign.com MHF Project # 305311 TABLE OF CONTENTS Section 1 Executive Summary Table 1: Drainage Summary Section 2 Narrative a) Project Description b) Methodology c) Existing Conditions Section 3 Post Development Stormwater Management Objectives DEP Stormwater Standards 1-10 o Recharge Calculations o TSS Removal Calculations o Rip Rap Outlet Calculations o Stage Storage Printouts o Drawdown Calculations o Mounding Analysis &Assumptions o DEP Checklist for Stormwater Report o Illicit Discharge Statement Appendix A—Maps & Data o USGS Map o MRCS Soils Maps o Test Pit Logs o Epsilon Associates Watershed Memo o Sand Filter Sizing Calculations Appendix B — Pre Development Drainage Calculations Appendix C —Post Development Drainage Calculations Appendix D —Post Development Increased Volume Computations Map Pockets o Pre Development Drainage Plan o Post Development Drainage Plan o Operation&Maintenance Plan&Long Term Pollution Prevention Plan for Stormwater Management Systems o Operation&Maintenance Plan Log Forms F:\Projects\Eng\305311\Drainage\Revised 3-25-13\305311-Drainage Report--Rev4.doc Revision 1: (12/7/12) • Revise layout of underground infiltration system • Add second infiltration system and underground detention system • Reduce site impervious coverage • Revise stormwater calcs,pre&post drainage summary table,drainage plans Revision 2: (1/28/13) • Update groundwater mounding calculations • Provide additional test pit logs • Raise infiltration system#2 per new logs • Update TSS calculations • Revise stormwater calcs,pre&post drainage summary table, drainage plans Revision 2: (3/1/13) • Raise infiltration system#2 • Update TSS calculations • Revise stormwater calcs,pre&post drainage summary table,drainage plans • Add Sand Filter Sizing calculations Revision 2: (3/25/13) • Revise stormwater calcs,pre&post drainage summary table,Post Development Drainage plan • Raise infiltration systems#1 &2,revise sizes • Update GRV&TSS calculations • Revise Sand Filter Sizing,Mounding&Drawdown calculations • Add Appendix D F:\Projects\Eng\305311\Drainage\Revised 3-25-13\30531 l-Drainage Report--Rev4.doc Section 1 EXECUTIVE SUMMARY The stormwater analysis for the proposed commercial development is designed using proven and accepted methods to meet or exceed state and local regulations for stormwater quantity and quality. Treatment, discharge rates and flood control measures have been incorporated to minimize downstream effects on abutting parcels and receiving areas. The study watershed area is approximately 31,000 sf that drains towards the eastern property line and the Osgood Street drainage system to the south. Onsite stormwater controls consist of a closed drainage system consisting of curbing and deep sump, hooded catch basins and trench drains discharging to a solid pipe detention and underground pipe and stone infiltration system prior to discharge to'the design points. Stormwater is also pretreated via an oil/water separator prior to discharging into the underground infiltration systems. A portion of the front of the site is treated with the use of an underground sand filter. Roof runoff will be discharged into the pipe and stone infiltration system for groundwater recharge. Additionally, a small paver patio located along the building front will be constructed using permeable pavers. For analysis purposes the site was modeled with a two (2) design points, DP#1,being the Osgood Street drainage system and DP#2 being the eastern property line. The summary below shows that there is no increase in the peak rates of runoff for the 1, 2, 10 & 100-year storm frequencies. Table l: Drainage Summary Peak Rates Design Storm Pre-Development Peak Post-Development Peak Change Rate of Runoff cfs Rate of Runoff cfs cfs #1OsoodSDraina e S stemDESIGNPOINT 1-year 0.18 0.16 -0.02 2-year 0.28 0.22 -0.06 10-year 0.57 0.57 0.00 100-year 0.99 0.92 -0.07 _ DESIGN PINT#2„ y _ 1- ear 0.27 0.24 -0.03 2-year 0.47 0.45 -0.02 10- ear 1.02 1.01 -0.01 [-100-year 1.87 2.12 0.25 (All values shown are peak rates in cubic feet per second(cfs)) Table 2: Drainage Sum ary Peak Volumes Design Storm Pre-Development Post-Development Change Peak Volume c Peak Volume c c DESIGN POINT#i Os ood Street Draina e S stem . 1- ear 638 1,203 +565 2= ear 983 1,680 +697 10- ear 1,905 2,864 +959 100-year 3,301 4,824 +1,523 (All values shown are peak volumes in cubic feet(cf)) F:\Projects\Eng\30531 1\Drainage\Revised 3-25-13\305311-Drainage Report--Rev4.doc Section 2 NARRATIVE a) Project Description: This project entitled Proposed Site Development Plans prepared for JFJ Holdings, LLC is located on a 28,127 sf parcel of land located at 1018 Osgood Street in North Andover, MA, Assessors Map 35 Lot 19. The site is located in the Business 2 (B-2)District along the north side of Osgood Street, south of the Lawrence Airport. JFJ Holdings, LLC is proposing to construct a 2,250 sf Donut Shop with drive thru. Development includes but is not limited to the building construction, a new 19 space parking lot layout, grading and associated utility connections. The site is accessed by a full access driveway along Osgood Street. The total onsite area of disturbance is approximately 25,000 sf, all of which is related to the construction of the site development and utility connections. The purpose of this report is to determine the pre- and post-development rates of stormwater runoff generated by this site and the impact of that runoff on the surrounding properties. b) Methodology: The drainage system for this project was modeled using HydroCAD, a stormwater modeling computer program that analyzes the hydrology, and hydraulics of stormwater runoff. HydroCAD uses either the Rational steady state method, or SCS hydrograph and routing procedures to estimate stormwater flow and volume. In HydroCAD, each watershed is modeled as a subcatchment, streams and culverts as reaches and ponds, and large wetlands and storage areas as ponds. SCS hydrograph and routing stormwater models were used for both Pre-development conditions and Post-development conditions. The Pre-development and Post-development watersheds and sub-area characteristics were determined using actual ground survey, and through visual inspection of runoff paths by walking the site. Conservative estimates were used at all times in evaluating the hydrologic characteristics of these watersheds. c) Existing Conditions Map 35 Lot 18 encompasses a 28,127 sf site and is currently occupied by a single family dwelling. In addition to the dwelling structure there is a detached garage and paved driveway within the site boundary. The site is surrounded by overgrown landscaping along the front and a wooded buffer along the sides and in the rear. The house and garage structures are elevated approximately 6-8' above the roadway and the slopes range from 2-10%throughout the site. FAProjects\E.ng\305311\Drainage\Revised 3-25-13\30531 l-Drainage Report--Rev4.doc Runoff generated from the existing development drains either easterly across the site or southerly into the Osgood Street drainage system. A small wetland pocket is also located along the northern corner of the lot. Any runoff generated from this development discharges further downstream into a larger wetland system along the north of Osgood Street, eventually discharging into the Merrimack River. In this case,none of the onsite runoff reaches Lake Cochichewick and this is outlined in more detail in the Wetlands Memo from Epsilon Associates dated September 15, 2012, found in Appendix A of this report. The on-site soils consist of Paxton (305B), & Urban Land (602), and described by Natural Resources Conservation Service (MRCS) as follows: Paxton series (SCS Classification "C") consists of gently sloping to very steep, deep (5+ feet), well-drained soils on drumlins. They formed in compact glacial till. Paxton soils have friable fine sandy loam surface soil and subsoil with moderate permeability over a firm or very firm fine sandy loam substratum (hardpan) at 15 to 38 inches which has slow or very slow permeability. Paxton soils have a very stony or extremely stony surface, except where stones have been removed, and have stones below the surface. Major limitations are related to slow permeability in the substratum, slope and stoniness. Urban land series (SCS Classification "none") consists of Urban land and a gently sloping and strongly sloping soils. The Urban land soil occurs as areas so intermingled that mapping them separately was not practical. The map unit is on broad plains and low hills that are partially covered by streets,parking lots, and buildings. Based on a portion of the site consisting of Urban land having no known hydrologic soil classification, the analysis used the hydrologic soil group classification C consistent with Paxton series soils present on remainder of the site. Additionally,test pits were performed onsite indicating loamy sand and sandy loam consistent with a"C" soil. FAProjects\Eng\30531 l\Drainage\Revised 3-25-13\30531]-Drainage Report--Rev4.doc Section 3 POST DEVELOPMENT References: 1. SCS - TRSS(Second Ed., 1986) - for runoff curve numbers. 2. SCS - Rainfall Distribution Maps. 3. NRCS Soils Maps -Essex County. 4. DEP—Stormwater Management Handbook This project is subject to both the D.E.P.'s Stormwater Management Policy and the North Andover Wetlands Protection By-law with work being proposed within 100 feet of a wetland. As shown herein,the proposed drainage system would provide the maximum feasible protection of groundwater resources, and prevent possible damage to abutting property or natural features in the area. In order to safeguard against oil or gas introduction into the drainage systems, storm water runoff from parking areas and driveways would be collected into hooded catch basins with deep sumps (see Site Plan Details). Such pretreatment of storm water reduces both suspended solids and oils in the drainage system and is recommended by DEP's Stormwater Management Handbook. Water quality would then further be treated by means of Oil/Water Separators designed to filter suspended solids/silt/debris. Before being discharged toward the property line,the flow rate would be controlled by means of an underground infiltration/detention system. Stormwater recharge is implemented by the underground recharge trenches (pipe and stone) which will infiltrate pretreated site parking and roof runoff. Another safeguard against future intrusion of contaminants into the groundwater is the implementation of an Operation & Maintenance Plan & Long Term Pollution Prevention Plan for Stormwater Management Systems (O&M& LTPPP), which would assure proper function of drainage components and reduce TSS entering the system. Further safeguards proposed on the Site Plan to prevent erosion include a line of silt fencing & hay bales during construction, soil stockpiling areas and loam and seed for permanent stabilization. If all the proposed erosion control devises and procedures are adhered to,then there should be no damage to neighboring properties from work on this site. The drainage system was designed utilizing a closed drainage system to achieve reduced rates of runoff at the points of analysis and would maintain a similar drainage pattern to the existing courses. The methodology is SCS TR-20, Type III rainfalls (1, 2, 10 & 100 year events). This is consistent with the requirements of the Town of North Andover and DEP's Storm water Management guidelines. All pertinent calculations represented in the following pages were developed utilizing Hydrocad Storm water modeling software. All pipes used on the project are to be High Density Polyethylene (HDPE) dual-wall (corrugated exterior, smooth interior). Pipe capacities and velocities are included in the Hydrocad printouts (as part of the data for each "pond" in Hydrocad terminology). FAProjects\Eng\305311\Drainage\Revised 3-25-13\305311-Drainage Report--Rev4.doc Stormwater Quality Controls: 1. Street Sweeping to capture sediment prior to entering the drainage system. This would be done on a scheduled basis. TSS Removal Rate= 5% 2. Hooded Catch Basins with Deep Sumps to capture, treat and redirect storm water toward the proposed underground detention system. TSS Removal Rate=25% 3. Oil/Water Separator to capture first flush(1/2" of runoff). TSS Removal Rate=25% 4. Infiltration Trenches to recharge pavement&roof areas. TSS removal rate= 80% 5. Underground Sand Filter to treat stormwater runoff. TSS removal rate= 80%. Groundwater Recharge: In order to provide the maximum possible groundwater recharge, the site plans have incorporated underground infiltration system to capture roof runoff and pretreated parking lot runoff. Calculations supporting the rates and capacities are included below. Storm water Quantity Controls: The Underground infiltration/detention systems were designed such that it would control discharges through outlet pipes for the 1, 2, 10 & 100-year events. The overall stormwater management system thereby achieves the following: • Control of runoff rates to abutting properties. • Water quality maintenance—TSS removal from storm water of more than 80%through street sweeping, deep sump hooded catch basin, Oil/Water Separators & Sand Filters. • Groundwater Recharge—through the infiltration systems. The points of analysis are the eastern property line and the Osgood Street drainage system. FAProjects\Eng\30531 I\Drainage\Revised 3-25-13\30531]-Drainage Report--ReO.doc Storm water Management & Water Quality Calculations: Note: All calculations are based on the area of proposed construction activities.Additional improvements to the existing site development are indicated on the Site Plan. Standard # 1: Untreated Stormwater No new storm water conveyances are to discharge untreated storm water directly to or cause erosion in wetlands or waters of the Commonwealth. Standard # 2: Post Development Peak Discharge Rates The storm water management system is designed so that post-development peak discharge rates do not exceed pre-development peak discharge rates. Standard # 3: Groundwater Recharge Proposed recharge system: Infiltration Trenches In accordance with Massachusetts stormwater policy, C soils require a Volume to recharge of 0.25 inches of runoff. Sub-watershed Area to the rear of the site: Proposed volume to be recharged: C-soils= 0.25 inches x lft/12" x (17,069 x 56.64 %Impervious)=201 c.£ required Total Volume Provided in Infiltration System#1 (Site Volume recharge provided=Volume stored in trenches (bottom of stone to invertout)): =Depth of stone x Length of field x Width of field x Void Ratio 477 c.f. (See attached Hydrocad Stage-Storage figure) 477 c.f. Total Vol. Recharged is> 201 c.£ required(4 ok) Sub-watershed Area to the front of the site: Proposed volume to be recharged: C-soils= 0.25 inches x lft/12" x (13,646 x 58.56 %Impervious) = 166 c.f. required Total Volume Provided in Infiltration System#2 (Site Volume recharge provided=Volume stored in trenches (bottom of stone to invertout)): =Depth of stone x Length of field x Width of field x Void Ratio 535 c.f. (See attached Hydrocad Stage-Storage figure) 535 c.f. Total Vol. Recharged is> 166 c.£ required(4 ok) F:\Projects\Eng\30531 I\Drainage\Revised 3-25-13\30531 1-Drainage Report--Rev4.doc Standard # 4: TSS Removal Storm water volume required to be treated for quality: = 1/2" x 1 ft/ 12"x 17,659 sf(developed) =736 c.f. = 1" x 1 ft/ 12"x 17,659 sf(developed) = 1,472 c.f. Required TSS Removal should be between 736 - 1,472 c.f. Volume required to be stored within Oil/Water Separator#1: = 13,156 x (73.49% impervious) x 1/2" x lft/12" =403 c.£ (minimum required) =403 c.£ x 7.48 gal/c.£ =3,014 gallons (Use a 3,000 gallon O/W Separator) Volume stored within Infiltration System#1 =477 c.f. (bottom of stone to invert out) Volume stored within Infiltration System#2 = 535 c.£ (bottom of stone to invert out) Total Volume stored/treated in infiltration system BMP's=477 c.£ + 535 c.£ = 1,012 c.f = 1,012 c.f. Total Volume Treated> 736 - 1,472 c.f. (4 ok) Explanation of systems: Parking and driveway areas would be pretreated by deep sump hooded Catch Basins and Oil/Water Separators prior to discharge into the underground infiltration/detention systems. Additional treatment for a portion of the front of the site will be accomplished through the use of an underground sand filter. Rooftop runoff would be routed into the underground infiltration system for recharge. Drainage Area BMP TSS Removal Rate Driveway/Parking Street Sweeping 5% Driveway/Parking Catch Basin w/sump 25% Driveway/Parking Oil/Water Separator 25% Driveway/Parking Underground Sand Filter 80% Roof/Driveway/Parking Infiltration Systems 80% Calculations: TSS Removal System 1: Driveway/Parking Areas (To Infiltration Systems#1): Beginning Load: 1.00 x Street Sweeping removal rate (0.05)=0.05 Load Remaining = 1.00—0.05 =0.95 Beginning Load: 0.95 x Catch Basin removal rate (0.25) =0.24 Load Remaining =0.95 —0.24 =0.71 Remaining Load: 0.71 x Oil/Water Separator(0.25) =0.18 Load Remaining =0.71 —0.18 FAProjects\Eng\30531 I\Drainage\Revised 3-25-13\305311-Drainage Report--Rev4.doc =0.53 (i.e. 47%Pretreatment Prior to discharge into Infiltration Systems, 44% minimum pretreatment required by DEP �ok) Remaining Load: 0.53 x Infiltration Systems removal rate (0.80)=0.42 Load Remaining = 0.50—0.42 =0.08 TSS Removal Rate=(1.00—0.08) =92% System 2: Driveway/Parking Areas (To Trench Drains #1 & 2): Beginning Load: 1.00 x Street Sweeping removal rate (0.05)=0.05 Load Remaining = 1.00—0.05 =0.95 Beginning Load: 0.95 x Sand Filtwer removal rate (0.80)=0.76 Load Remaining =0.95 —0.76 = 0.19 TSS Removal Rate= (1.00—0.19) = 81% Standard # 5: Higher potential pollutant loads The site does not contain land uses with higher potential pollutant loads. Standard # 6: Protection of critical areas The site does not contain critical areas with sensitive resources. Standard # 7: Redevelopment proiects This site is not a redevelopment project. Standard # 8: Erosion/sediment control Erosion and sediment controls are incorporated into the project design to prevent erosion. Standard #9: Operation/maintenance plan Post-Development Phase See Operation and Maintenance Plan and Long Term Pollution Prevention Plan in the back of this report for additional information. The owner is to be responsible for maintenance of all drainage structures in the project- including but not limited to drain pipes, structures and detention/infiltration systems. F:\Projects\Eng\305311\Drainage\Revised 3-25-13\305311-Drainage Report--Rev4.doc Standard #10: Illicit Discharges: To the best of our knowledge,the site does not contain any illicit discharges, see attached Discharge Statement. FAProjects\Eng\305311\Drainage\Revised 3-25-13\305311-Drainage Report--Rev4.doc OUTLET APRON DESIGN IMMMW ■� Project: JFJ Holdings,LLC Job# 305311 .era I ® s r �! Date: Revised 12/7/12 FES#1 OUTLET APRON = Outlet# (from HydroCAD POND INF1) MHF Design Consultants, Inc. Q10= 0.66 cfs Do= 12 inches ENGINEERS • PLANNERS SURVEYORS Tw= 0.7 feet Design Criteria Apron Dimensions The dimensions of the apron at the outlet of the pipe shall be determined as follows: 1.) The width of the apron at the outlet of the pipe or channel shall be 3 times the diameter of the pipe of width of the channel. W= 3 feet 2.) The length of the apron shall be determined from the following formula when the tailwater depth at the outlet of the pipe or channel is less than one-half the diameter of the pipe or one-half the width of the channel: La=1.8*Q/DOA 3/2+7Do La= 8.19 feet Where: La is the length of the apron Q is the discharge from the pipe or channel Do is the diameter of pipe of width of channel 3.) When the depth of the tailwater at the outlet of the pipe or channel is equal to or greater than one-half the diameter of the pipe or the width of the channel.Then the following formula applies: La=3.0*Qo/Do/11.5+7Do La= 8.98 feet 4.) Where there is no well defined channel downstream of the outlet,the width of the downstream end of the apron shall be determined as follows: a. For minimum tailwater conditions where the tailwater depth is less than the elevation of the center of the pipe: W=3*Do+La W= 11.19 feet b. For maximum tailwater conditions where the tailwater depth is greater than the elevation of the center of the pipe: INF-HW1 W=3*Do+0.4*La W= 6.59 feet 5.) Where there is a stable well-defined channel downstream of the apron, the bottom of the apron shall be equal to the width of the channel. 6.) The side of the apron in a well-defined channel shall be 2:1 (horizontal to vertical)or flatter. The height of the structural lining along the channel sides shall begin at the elevation equal to the top of conduit and taper down to the channel bottom through the length of the apron. 7.) The bottom grade of the apron shall be level(0%grade). No overfall is allowable at the end of the apron. 8.) The apron shall be located so that there are no bends in the horizontal alignment of the apron. Rock Riprap The following criteria shall be used to determine the dimensions of the rock riprap used for the apron: 1.) The median stone diameter shall be determined using the formula: d5o 0.02*Q^4/3/(Tw*Do) d50= 0.20 inches USE 3 inches d50 minimum 3 inches Where: d50 is the median stone diameter in feet Tw is the tailwater depth above the invert of the pipe channel in feet Q is the discharge from the pipe or channel in cubic feet per second Do is the diameter of the pipe or width of the channel in feet 2.) Fifty percent by weight of the riprap mixture shall be smaller the than median size stone designated as d50. The largest stone size in the mixture shall be 1.5 times the d5o size. 3.) The quality and gradation of the rock,the thickness of the riprap lining,filter material and the quality of the stone shall meet the requirements in the Rock Riprap BMP. The minimum depth shall be 6 inches or 1.5 times the largest stone size in the mixture whichever is larger(d). Thickness of the riprap d= 1.5*(1.5*d5o(largest stone size)) d= 7 inches* *must use a minimum of 6" Rock Rip Rap Gradation %of weight smaller than the given size size of stone in inches 100 4.5 to 6.0 85 3.9 to 5.4 50 3.0 to 4.5 15 0.9 to 1.5 INF- HW1 _MONNEWENnMr _I �_ MHF Project No. 305311 Sheet i of 1 Project Description JFJ Holdings,LLC Task Pond Drawdown Calculations MI-IF DeSlgrt Consultants, Inc. Calculated By CMT Date Rev 3/25/13 Checked By Date ENGINEERS PLANNERS • SURVEYORS Drawdown within 72 hours Analysis for Static Method Underground Infiltration System#1 Infiltration Rate: 0.2 inches/hour(From table 2.3.3: Rawls, Brakensiek, Saxton, 1982) Design Infiltration Rate: 0.20 inches/hour Volume Provide for Infiltration: 477 cf Basin bottom area: 1,087 sf Time drawdown = (Required Recharge Volume in cubic feet as determined by the Static Method)(1/Design Infiltration Rate in inches per hour)(conversion for inches to feet)(1/bottom area in feet) Time drawdown = ( 477 co ( 1 / 0.20 in/hr) (1ft/12 in.) ( 1 / 1,087 sf) 26.32 hours Underground Infiltration System#2 Infiltration Rate: 0.2 inches/hour(From table 2.3.3:Rawls, Brakensiek, Saxton, 1982) Design Infiltration Rate: 0.20 inches/hour Volume Provide for Infiltration: 535 cf Basin bottom area: 1,006 sf Time drawdown = (Required Recharge Volume in cubic feet as determined by the Static Method)(1/Design Infiltration Rate in inches per hour)(conversion for inches to feet)(1/bottom area in feet) Time drawdown = ( 535 cf) ( 1 / 0.20 in/hr) (1ft/12 in.) ( 1 / 1,006 sf) 31.92 hours 305311 24-hr Pond Drain Calc--Rev4.xls 305312-Postdrain--ReA Type III24-hr 1/2-inch Rainfall=0.50" Prepared by MIIF Design Consultants,Inc Printed 3/28/2013 HydroCAD®10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond INF1: PROP UG INFILTRATION SYSTEM-1 Elevation Surface Storage (feet) (sq-ft) (cubic-feet) 141.67 1,087 0 141.72 1,087 22 141.77 1,087 43 141.82 1,087 65 141.87 1,087 87 141.92 1,087 109 141.97 1,087 130 142.02 1,087 152 142.07 1,087 170 142.12 1,087 188 142.17 1,087 207 142.22 1,087 233 142.27 1,087 261 142.32 1,087 291 142.37 1,087 322 142.42 1,087 354 142.47 1,087 388 142.52 1,087 422 42.57 1,087 456 477 "° 142.62 1,087 491 142.67 1,087 527 142.72 1,087 562 142.77 1,087 598 142.82 1,087 633 142.87 1,087 668 142.92 1,087 703 142.97 1,087 738 143.02 1,087 772 143.07 1,087 806 143.12 1,087 838 143.17 1,087 870 143.22 1,087 900 143.27 1,087 928 143.32 1,087 954 143.37 1,087 976 143.42 1,087 992 143.47 1,087 1,010 143.52 1,087 1,030 143.57 1,087 1,052 143.62 1,087 1,074 143.67 1,087 1,096 143.72 1,087 1,117 143.77 1,087 1,139 143.82 1,087 1,161 305312-Postdrain--Rev4 Type 11124-hr 1/2-inch Rainfall=0.50" Prepared by MHF Design Consultants,Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond INF2: PROP UG INFILTRATION SYSTEM-2 Elevation Surface Storage (feet) (sq-ft) (cubic-feet) 143.67 1,006 0 143.72 1,006 20 143.77 1,006 40 143.82 1,006 60 143.87 1,006 80 143.92 1,006 101 143.97 1,006 121 144.02 1,007 140 144.07 1,008 158 144.12 1,009 173 144.17 1,010 191 144.22 1,010 215 144.27 1,011 240 144.32 1,011 268 144.37 1,011 296 144.42 1,011 326 144.47 1,012 356 144.52 1,012 387 144.57 1,012 419 144.62 1,012 451 144.67 1,012 483 7s144.72 1,012 516 144.77 1,012 548 144.82 1,012 581 144.87 1,011 613 144.92 1,011 645 144.97 1,011 677 145.02 1,010 708 145.07 1,010 739 145.12 1,009 768 145.17 1,009 797 145.22 1,007 825 145.27 1,006 851 145.32 1,006 875 145.37 1,006 895 145.42 1,006 910 145.47 1,006 927 145.52 1,006 946 145.57 1,006 966 145.62 1,006 986 145.67 1,006 1,006 145.72 1,006 1,026 145.77 1,006 1,046 145.82 1,006 1,066 -nwo --->y5TEK -&Z. view cart check out March 28, 2013 You can also perform mounding calculations with graphical display uYs'ing:,Hydrus �I Saturated/Unsaturated Flow& Transport Model GroundwaterSoftware,com Calculator 9 - Groundwater Mounding Calculator • GROUNDWATER MOUND UNDER RECTANGULAR RECHARGE AREA Using the Hantush (1967) Derivation 'hic. . • . .ton, MA, 01450 Back to Calculators .00 '1978) 477-0250 The equation representing the groundwater mound beneath a -Here rectangular recharge area is given by: hen-1� = (2wIK)vtS*((0.5L/( 4 i%(0.5WI( 4vt)}� where: v=WE b=0.5(4(0)+h(t)) where h,,, is the maximum height of the mound; hi is the initial height of the water table; w is the recharge or percolation rate; K is the hydraulic conductivity; t is the time of interest; L and W are the length and width of the rectangular recharge area, and e is the specific yield of the aquifer. S* is an integral equation given by: 7 S*(a,p) - �erf( )•erf(k)dT This equation is estimated in the calculator by using a table of values given by Hantush (19671. GROUNDWATER MOUND UNDER A RECTANGULAR RECHARGE AREA Using the Hantush (1967) Derivation Inputs w(Percolation Rate): [UT] K(Hydraulic Conductivity): [LIT] S(Specific Yield): 32 [-] t(Time): 31.92 [T] hi(Initial Saturated Thickness): 110 , [L] a(Length of Recharge Area): 34 [L] b(Width of Recharge Area): 30 [L] **KEEP UNITS CONSISTENT** Results **Note that because of estimations of an integral function, this is an estimate* Maximum hydraulic head: 10.99750000 [L] Increase in hydraulic head: 0.9975000 [L] Hantush, M.S.(1967). Growth and Decay of Groundwater-Mounds in Response to Uniform Percolation, Water Resources Research vol. 3, no.1, pp 227-234. Example: What is the maximum mounding at the water table if 1000 liters/day of water is discharged on an area 3 x 4 m after 2 days (all water infiltrates). Given a hydraulic conductivity of 1 X10-6 m/s, and specific yield of 0.01 and an initial saturated thickness of 2 m. Your results should yield a maximum hydraulic head of approximately 3.3 m and an increase in hydraulic head of 1.3 m. What might have gone wrong? - converting from 1000 liters/day to m/day. Convert to m3/day using 1000 liters/m3, then divide by area to get the m/day of water infiltrating. This value should be approximately 0.08 m/day -converting the hydraulic conductivity to units of m/day. This value should be approximately 0.086 Summary Inputs w = 0.08 m/day, K= 0.086m/day, S=0.01, t = 2 days, hi = 2 m, a = 3m, b= 4m Results Maximum hydraulic head = 3.3 m Increase in hydraulic head = 1.3 m See our Newsletter on Groundwater Mound Under a Rectangular Recharge Area and December S en cials o GroundwaterS oftware.com home* sell here* security• about us _WOMMONNNOMMW NNEOM' �_ �� MHF Project No. 305311 Sheet 2 of 2 Project Description JFJ Holdings,LLC Task Mounding Calcs MHF ®@S1gn Consultants, Inc. Calculated By CMT Date Rev 3/25/13 Checked By Date ENGINEERS - PLANNERS • SURVEYORS Backup Calculations for Mounding Analysis Underground Infiltration System#2 Using the Groundwater Mounding Calculator and the Hantush Mounding Software the following information is input into the program to calculate the groundwater mound under a rectangular recharge area. W= Flow rate through system for a 10-year design storm event-[ FT/HR] Q= 0.3 cfs W= 1.00 K(Hydraulic Conductivity) = From attached Figure-[FT/HR] K Value for (Taken from the MRCS Soil Mapping for Paxton Soils) K= 0.10 (average value) S (Specific Yield ) = From Attached Figure-[-] S Value for Sand, medium S= 32 t(Time) = Drawdown Time calculated -[HR] t= 31.92 hi (Initial Saturated Thickness) = Based on eshwt-[Elev. FT] hi = 10 a (Length of recharge area) -[FT] a= 34 b (Width of recharge area) [FT] b= 30 305311 Mounding Calcs Backup Info--Rev4.x1s Hydraulic Properties :. Aquifer Testing 101 Page 6 of 7 where n is total porosity [dimensionless], Sy is specific yield [dimensionless] and Sr is specific retention [dimensionless], the amount of water retained by capillary forces during gravity drainage of an unconfined aquifer. Thus, specific yield, which is sometimes called effective porosity, is less than the total porosity of an unconfined aquifer(Bear 1979). Heath (1983) reports the following values (in percent by volume) for porosity, specific yield and specific retention: Material Porosity(%) Specific Specific Yield(%) Retention(%) Soil 55 40 15 Clay 50 K22 48 Sand 25 3 Gravel 20 1 Limestone 20 2 Sandstone(unconsolidated) 11 5 Granite 0.1 0.01 Basalt(young) 11 3 The following table shows representative values of specific yield for various geologic materials (from Morris and Johnson 1967): Material Specific Yield(%) Gravel,coarse 21 Gravel, medium 24 Gravel,fine 28 Sand,coarse 30 Sand, medium 32 Sand,fine 33 Silt 20 Clay 6 Sandstone,fine grained 21 Sandstone, medium grained 27 Limestone 14 Dune sand 38 Loess 18 Peat 44 Schist 26 Siltstone 12 Till,predominantly silt 6 Till,predominantly sand 16 Till,predominantly gravel 16 Tuff 21 Porosity (n) V, oo Qa w�000 lQn a � � uo QrY co�c oPo D U P o c v 4PocovPP aisa . r_, o0 oae ooP a . OOPO�POO .i 'Volume of voids ` V) C.? m3 Porosity (n)- -- = = 0.30 Intal volume ILS) l.") m3 Void volume, total volume and porosity(from Heath 1983). Porosity is defined as the void space of a rock or unconsolidated material: http://www.agtesolv.com/aquifer-tests/aquifer properties.htm 10/5/2012 ff k view cart u check out January 28, 2013 You can also perform mounding calculations with graphical display using: ;. Hydrus r Saturated/Unsaturated Flow& Transport Model Gmundwatedottwarexom Calculator 9 - Groundwater Mounding Calculator GROUNDWATER MOUND UNDER A RECTANGULAR RECHARGE /AREA Using the Hantush (1967) Derivation -hic. . 01450 Back to Calculators .00 '-(978) 477-0250 The equation representing the groundwater mound beneath a IdL t Us-, rectangular recharge area is given by: hS —h� = (2w/K)vtS*((Q.5L f where v=KblE b=0.5(4(0)+h(t)) where h. is the maximum height of the mound; hl is the initial height of the water table; w is the recharge or percolation rate; K is the hydraulic conductivity; t is the time of interest; L and W are the length and width of the rectangular recharge area, and e is the specific yield of the aquifer. S* is an integral equation given by: 1 S*(a,R) _ erf(')•erf(k)dr This equation is estimated in the calculator by using a table of values given by Hantush (19671. GROUNDWATER MOUND UNDER A RECTANGULAR RECHARGE AREA Using the Hantush (1967) Derivation Inputs w(Percolation Rate): 3.94 [LIT] K(Hydraulic Conductivity) 1 [L/Tl S(Specific Yield): t(Time): 12.37 [T] hi(Initial Saturated Thickness): 10 LLl a(Length of Recharge Area): 20 [L] b(Width of Recharge Area): 44 [Ll **KEEP UNITS CONSISTENT** caNmK Results **Note that because of estimations of an integral function, this is an estimate** Maximum hydraulic head: 11.52305625 [L] Increase in hydraulic head: 11.52K5 [L] Hantush, M.S.(1967). Growth and Decay of Groundwater-Mounds in Response to Uniform Percolation, Water Resources Research vol. 3, no.1, pp 227-234. Example: What is the maximum mounding at the water table if 1000 liters/day of water is discharged on an area 3 x 4 m after 2 days (all water infiltrates). Given a hydraulic conductivity of 1 x10"6 m/s, and specific yield of 0.01 and an initial saturated thickness of 2 m. Your results should yield a maximum hydraulic head of approximately 3.3 m and an increase in hydraulic head of 1.3 m. What might have gone wrong? - converting from 1000 liters/day to m/day. Convert to m3/day using 1000 liters/m3, then divide by area to get the m/day of water infiltrating. This value should be approximately 0.08 m/day -converting the hydraulic conductivity to units of m/day. This value should be approximately 0.086 Summary Inputs w = 0.08 m/day, K= 0.086m/day, S=0.01, t = 2 days, hi = 2 m, a = 3m, b= 4m Results Maximum hydraulic head = 3.3 m Increase in hydraulic head = 1.3 m See our Newsletter on Groundwater Mound Under a Rectangular Recharge Area and December Specials o OrourldwaterSoftwarexom home- sell here* security* about us _SOMMEENNNOMW _® _® '� MHF Project No. 305311 Sheet 1 of 2 Project Description JFJ Holdings,LLC -- Task Mounding Calcs MFIF Design Consultants, Inc. Calculated By CMT Date Rev 3/25/13 Checked By Date ENGINEERS a PLANNERS • SURVEYORS Backup Calculations for Mounding Analysis Underground Infiltration System#1 Using the Groundwater Mounding Calculator and the Hantush Mounding Software the following information is input into the program to calculate the groundwater mound under a rectangular recharge area. W= Flow rate through system for a 10-year design storm event-[ FT/HR] Q= 1.2 cfs W= 4.11 K(Hydraulic Conductivity) = From attached Figure-[FT/HR] K Value for (Taken from the NRCS Soil Mapping for Paxton Soils) K= 0.10 (average value) S (Specific Yield ) = From Attached Figure-[-] S Value for Sand, medium S= 32 t(Time) = Drawdown Time calculated -[HR] t= 26.32 hi (Initial Saturated Thickness) = Based on bottom of Test Pits-[Elev. FT] hi = 10 a (Length of recharge area) - [FT] a= 34 b (Width of recharge area) [FT] b= 32 305311 Mounding Calcs Backup Info--Rev4.x1s Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for 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, ort(which hih hld t St the Stormwater e wcsouprovide more substantive and detailed information use only the tab p 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 Qcertified 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. 305311-NOlswcheck.doc• Stormwater Report Checklist•Page 1 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for 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 I 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 0F ' -.c FPANK C. M�ONTL`;IR16 CIVIL No.36341 o� OSTERtia NAL Signa re and D e Checklist Project Type: Is the application for new development, redevelopment, or a mix of new and redevelopment? ® New development ❑ Redevelopment ❑ Mix of New Development and Redevelopment 305311-NOlswcheck.doc• 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: ® 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): Permeable Pavers Standard 1: No New Untreated Discharges ® 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. 305311-NOlswcheck.doc• Stormwater Report Checklist•Page 3 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for 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. ® 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 ® Soil Analysis provided. ® 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 ❑ Simple Dynamic ❑ Dynamic Field' ❑ Runoff from all impervious areas at the site discharging to the infiltration BMP. ❑ 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. ❑ Recharge BMPs have been sized to infiltrate the Required Recharge Volume only to the maximum extent practicable for the following reason: ❑ Site is comprised solely of C and D soils and/or bedrock at the land surface ❑ M.G.L. c. 21E sites pursuant to 310 CMR 40.0000 ❑ Solid Waste Landfill pursuant to 310 CMR 19.000 ❑ Project is otherwise subject to Stormwater Management Standards only to the maximum extent practicable. ® Calculations showing that the infiltration BMPs will drain in 72 hours are provided. ❑ Property includes a M.G.L. c. 21E site ora 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. 305311-NOlswcheck.doc• Stormwater Report Checklist•Page 4 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 3: Recharge (continued) ® 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. ® 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. ® Calculations documenting that the treatment train meets the 80%TSS removal requirement and, if applicable, the 44% TSS removal pretreatment requirement, are provided. 305311-NOlswcheck.doc• Stormwater Report Checklist•Page 5 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 4:Water Quality (continued) ® The BMP is sized (and calculations provided) based on: ® The %"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. ❑ 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. 305311-NOlswcheck.doc• Stormwater Report Checklist•Page 6 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for 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 ❑ Redevelopment portion of mix of new and redevelopment. ❑ 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. ❑ 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; • 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. ® A Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan containing the information set forth above has been included in the Stormwater Report. 305311-NOlswcheck.doc• Stormwater Report Checklist•Page 7 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for 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. ❑ 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: ® Name of the stormwater management system owners; ® Party responsible for operation and maintenance; ® Schedule for implementation of routine and non-routine maintenance tasks; ® Plan showing the location of all stormwater BMPs maintenance access areas; ❑ Description and delineation of public safety features; ❑ Estimated operation and maintenance budget; and ® 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; ® 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. 305311-NOlswcheck.doc• Stormwater Report Checklist•Page 8 of 8 44 Stiles Road •Suite One• Salem, New Hampshire 03079 TEL (603) 893-0720 • FAX (603) 893-0733 MHF Design Consultants, Inc. www.mhfdesign.com October 19, 2012 Ms. Jennifer Hughes, Conservation Administrator North Andover Conservation Commission 1600 Osgood Street, Suite 264 North Andover, MA 01845 Re: 1018 Osgood Street Map 35 Lot 19 JFJ Holdings, LLC Sub: Illicit Discharge Statement Standard#10 Dear Ms. Hughes: On behalf of our client, JFJ Holdings, LLC,we hereby state that to the best of our knowledge, no illicit discharges exist on the above referenced site and none are proposed with the site development plans as prepared for the above referenced site. Implementing the pollution prevention plan measures outlined in the site development plans will prevent illicit discharges to the stormwater management system, including wastewater discharges and discharges of stormwater contaminated by contact with process wastes, raw materials, toxic pollutants,hazardous substances, oil, or grease. .t" OF Sincerely, o scy MH F si Consultants, Inc. FRANK 0. MONTEIRO CIVIL � No. 36341 o� GiR; �t�� r C. 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(( ''� USDA United States A product of the National Custom Soil Resource Department of Cooperative Soil Survey, Agriculture a joint effort of the United Report for States Department of Agriculture and otherV RCS Essex County,Federal agencies, State Natural agencies including the Massachusetts Resources Agricultural Experiment ' Conservation Stations, and local Service participants Northern Part t 1. .r w 2` f, r x �c ryry i September 26, 2012 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect,or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning,onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://soils.usda.gov/sqi/)and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center(http://offices.sc.egov.usda.gov/locator/app? agency=nres) or your NRCS State Soil Scientist(http://soils.usda.gov/contact/ state offices/). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey orwet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Soil Data Mart Web site or the NRCS Web Soil Survey. The Soil Data Mart is the data storage site for the official soil survey information. The U.S. Department of Agriculture(USDA)prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal,or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means 2 for communication of program information (Braille, large print, audiotape, etc.)should contact USDA's TARGET Center at(202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or(202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface.............................. .. ................................ ....................................................2 How Soil Surveys Are Made..................................................................................5 SoilMap..................................................................................................................7 SoilMap................................................................................................................8 Legend..................................................................................................................9 MapUnit Legend................................................................................................10 MapUnit Descriptions........................................................................................10 Essex County, Massachusetts, Northern Part................................................12 3056—Paxton fine sandy loam, 3 to 8 percent slopes................................12 602—Urban land.........................................................................................13 Soil Information for All Uses...............................................................................14 Soil Properties and Qualities..............................................................................14 Soil Qualities and Features.............................................................................14 HydrologicSoil Group.................................................................................14 References................. .......................................................................................19 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area.They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles.A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform,a soil scientist develops a concept,or model,of how they were formed.Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil scientists classified and named the soils in the survey area, they compared the 5 Custom Soil Resource Report individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil- landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests.Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and identified each as a specific map unit.Aerial photographs show trees, buildings,fields, roads, and rivers, all of which help in locating boundaries accurately. 6 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 7 N N A A N n? A 4731200 4731220 4731240 4731260 4731260 4731300 4731320 4731340 4731360 71-7'6" 71 7 6 j � r tw�z v 3 1 Ez� � x 0 0 O OJ � t 2, ✓ �. 'L 'e k t� � '��.a i�d a. rn t 's' � 0 m b �� '7a c°'n z'�e` a ;s t �r kt� y t vY' �Y" Wit`'•'` � MO Nj O U)O W O 0 CDk CD � ILII 11 O n Y 4 v �iY t t t 'Yt s N 1kY � � t � Ot 1 O 71°7.0.. 71°7'0'• 4731200 473 220 4731240 4731260 4731280 4731300 4731320 4731340 4731360 N N N N Custom Soil Resource Report MAP LEGEND MAP INFORMATION Area of Interest(AOI) Very Stony Spot Map Scale: 1:881 if printed on A size(8.5"x 11")sheet. El Area of Interest(AOI) Wet Spot The soil surveys that comprise your AOI were mapped at 1:15,840. Soils A. Other Soil Map Units Special Line Features Warning:Soil Map may not be valid at this scale. Special Point Features Gully Blowout Short Steep Slope Enlargement of maps beyond the scale of mapping can cause ® Borrow Pit misunderstanding of the detail of mapping and accuracy of soil line Other placement.The maps do not show the small areas of contrasting X Clay Spot Political Features soils that could have been shown at a more detailed scale. 4 Closed Depression 0 Cities X Gravel Pit Water Features Please rely on the bar scale on each map sheet for accurate map Gravelly Spot Streams and Canals measurements. Landfill Transportation Source of Map: Natural Resources Conservation Service /t Lava Flow +++ Rails Web Soil Survey URL: http://websoilsurvey.nres.usda.gov Coordinate System: UTM Zone 19N NAD83 4L, Marsh or swamp Interstate Highways .R Mine or Quarry US Routes This product is generated from the USDA-NRCS certified data as of the version date(s)listed below. p Miscellaneous Water Major Roads Q Perennial Water Local Roads Soil Survey Area: Essex County,Massachusetts, Northern Part Survey Area Data: Version 8,Aug 11,2008 v Rock Outcrop + Saline Spot Date(s)aerial images were photographed: 7/10/2003 Sandy Spot The orthophoto or other base map on which the soil lines were Severely Eroded Spot compiled and digitized probably differs from the background imagery displayed on these maps.As a result,some minor shifting p Sinkhole of map unit boundaries may be evident. Slide or Slip Id Sodic Spot _, Spoil Area ,a Stony Spot Custom Soil Resource Report Map Unit Legend Essex County,Massachusetts,Northern Part(MA605) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 305B Paxton fine sandy loam,3 to 8 1.3 82.5% percent slopes 602 Urban land 0.3 17.5% Totals for Area of Interest 1.5 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils.On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management.These are called contrasting,or dissimilar,components.They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that itwas impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. 10 Custom Soil Resource Report An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps.The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha- Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. 11 Custom Soil Resource Report Essex County, Massachusetts, Northern Part 3056—Paxton fine sandy loam, 3 to 8 percent slopes Map Unit Setting Mean annual precipitation:45 to 54 inches Mean annual air temperature:43 to 54 degrees F Frost-free period: 145 to 240 days Map Unit Composition Paxton and similar soils:90 percent Minor components: 10 percent Description of Paxton Setting Landform: Drumlins Landform position (two-dimensional): Summit, shoulder Landform position (three-dimensional): Nose slope, crest Down-slope shape: Convex Across-slope shape: Convex Parent material: Friable coarse-loamy eolian deposits over dense coarse-loamy lodgment till derived from granite and gneiss Properties and qualities Slope: 3 to 8 percent Depth to restrictive feature. 18 to 32 inches to dense material Drainage class:Well drained Capacity of the most limiting layer to transmit water(Ksat):Very low to moderately high (0.00 to 0.20 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water capacity.Very low (about 2.8 inches) Interpretive groups Land capability(nonirrigated):2e Typical profile 0 to 6 inches: Fine sandy loam 6 to 21 inches: Fine sandy loam 21 to 60 inches: Gravelly fine sandy loam Minor Components Ridgebury Percent of map unit: 5 percent Landform: Depressions Woodbridge Percent of map unit: 5 percent 12 Custom Soil Resource Report 602—Urban land Map Unit Setting Frost-free period: 125 to 165 days Map Unit Composition Urban land: 80 percent Minor components: 20 percent Description of Urban Land Setting Parent material: Excavated and filled land Minor Components Udorthents Percent of map unit: 10 percent Charlton Percent of map unit: 2 percent Hinckley Percent of map unit: 2 percent Merrimac Percent of map unit:2 percent Paxton Percent of map unit: 2 percent Windsor Percent of map unit: 2 percent 13 Soil Information for All Uses Soil Properties and Qualities The Soil Properties and Qualities section includes various soil properties and qualities displayed as thematic maps with a summary table for the soil map units in the selected area of interest.A single value or rating for each map unit is generated by aggregating the interpretive ratings of individual map unit components. This aggregation process is defined for each property or quality. Soil Qualities and Features Soil qualities are behavior and performance attributes that are not directly measured, but are inferred from observations of dynamic conditions and from soil properties. Example soil qualities include natural drainage, and frost action. Soil features are attributes that are not directly part of the soil. Example soil features include slope and depth to restrictive layer.These features can greatly impact the use and management of the soil. Hydrologic Soil Group 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. 14 Custom Soil Resource Report 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. 15 Custom Soil Resource Report Map—Hydrologic Soil Group io 0 326540 326560 326580 326600 326620 326640 326660 42°42'55" 42°42'55" m � d v K O O O O N M r. f 0 � „ v mN, N {'r N M C1 � x m y N N � m "x•'�_:N- - .�. .i-mac`- - -', 7 gg 20 42°42'49" 42'42'49" 326540 326560 326580 326600 326620 326640 326660 io Map Scale:1:881 if printed on A size(8.5"x 11")sheet. o _ N mwnm====zmmmwmmnm=======Meters n 0 5 10 20 30 Feet 0 30 60 120 180 Custom Soil Resource Report MAP LEGEND MAP INFORMATION Area of Interest(A01) Map Scale: 1:881 if printed on A size(8.5"x 11")sheet. E-1 Area of Interest(AOI) Soils The soil surveys that comprise your AOI were mapped at 1:15,840. Soil Map Units Soil Ratings Warning:Soil Map may not be valid at this scale. A Enlargement of maps beyond the scale of mapping can cause A/D misunderstanding of the detail of mapping and accuracy of soil line placement.The maps do not show the small areas of contrasting B soils that could have been shown at a more detailed scale. F-1 B/D EJ C Please rely on the bar scale on each map sheet for accurate map CID measurements. 0 D Source of Map: Natural Resources Conservation Service Not rated or not available Web Soil Survey URL: http://websoilsurvey.nres.usda.gov Coordinate System: UTM Zone 19N NAD83 Political Features .0 Cities This product is generated from the USDA-NRCS certified data as of Water Features the version dates)listed below. Streams and Canals Soil Survey Area: Essex County,Massachusetts,Northern Part Transportation Survey Area Data: Version 8,Aug 11,2008 Rails Interstate Highways Date(s)aerial images were photographed: 7/10/2003 US Routes The orthophoto or other base map on which the soil lines were Major Roads compiled and digitized probably differs from the background imagery displayed on these maps.As a result,some minor shifting y,} Local Roads of map unit boundaries may be evident. Custom Soil Resource Report Table—Hydrologic Soil Group Hydrologic Soil Group—Summary by Map Unit—Essex County,Massachusetts,Northern Part(MA605) Map unit symbol Map unit name Rating Acres in A01 Percent of AOI 3058 Paxton fine sandy loam,3 to C 1.3 82.5% 8 percent slopes 602 Urban land 0.3 17.5% Totals for Area of Interest 1.5 100.0% Rating Options—Hydrologic Soil Group Aggregation Method: Dominant Condition Component Percent Cutoff. None Specified Tie-break Rule: Higher 18 References American Association of State Highway and Transportation Officials(AASHTO).2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt,G.W.,and L.M.Vasilas,editors.Version 6.0,2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://soils.usda.gov! Soil Survey Staff. 1999. Soil taxonomy:A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http://soils.usda.gov/ Soil Survey Staff. 2006. Keys to soil taxonomy. 10th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http://soils,usda.gov/ Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://soils.usda.gov/ United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.glti.nres.usda.gov/ United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 4304I, http://soils.usda.gov/ United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http-.//soils.usda.gov/ 19 Custom Soil Resource Report United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. 20 FORM It - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street,North Andover MA On-site Review Deep Hole Number:....812..1 ... . ....... Date: 8/9/12 .. Time: Weather 90s._Suy. nn ...._..... Location(identify on site plan)___.. Land Use .Former.Residence---.. ............. Slope_(%) .0_-5.0 Surface_Stones, _None visible.....,....._......_..._. Vegetation..Grass,.Trees,.Shrubs ..... ._,._.._... Landform . .......................... .....__.. _. ._ ... Position on landscape(sketch on back) Distances from: Open Water Body._-?-J-09-.- feet Drainage way. .................... feet Possible Wet Area ...>50................__...._..._. feet Property Line >10_._,....__..._.__._.. feet Drinking Water Well >I00_._..._._..__ feet Other . DEEP OBSERVATION HOLE LOG* Depth from Soil Horizon Soil Texture Soil Color Soil Mottling Other Surface(Inches) (USDA) (Munsell) (Structure,Stones,Boulders, Consistency,%Gravel) 0-9" A Loamy Sand l oyr 4/6 9-12" B Loamy Sand IOyr 7/6 12-86" C Sandy Loam 2.5y 7/4 @ 36" Stones,Cobbles,Boulders Faint 86" R MINIMUM OF 2 HOLES REQUIRED AT EVERY PROPOSED DISPOSAL AREA Parent Material (geologic): Till..._..___ _ Depth to Bedrock: >86" ... Depth to Groundwater: 3.6'.'. Standing Water in Hole: None _ _ ,_...,..,,.,_.. Weeping from pit face: None-........... . ,..__,.. Estimated Seasonal High Groundwater: 36" DEP APPROVED FORM-12/07/95 FORM 11 - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street North Andover MA On-site Review Deep Hole Number:....812-2...._ ........_ Date: ._8/9/12........ .........__. Time:...... .. Weather: .90s Sunny.._.._.. Location(identify on site plan) _. Land Use Former Residence......._._..............._._....._......_._ Slope._(%),. 0-5% Surface_StonesNone visible ..__ ....... _ Vegetation _Grass,.Trees, Shrubs._..__. ._ Landform ............... . ....... ......... ......... ......._...... .. ..... _ ._...... Position on landscape(sketch on back) Distances from: Open Water Body_._>100 _.. _ feet Drainage way _>50.__ feet Possible Wet Area __.>50...__ feet Property Line.. >10.................___.__ feet Drinking Water Well.,>1.0.0_. _..__.___ feet Other ............ . . DEEP OBSERVATION HOLE LOG* Depth from Soil Horizon Soil Texture Soil Color Soil Mottling Other Surface(Inches) (USDA) (Munsell) (Structure,Stones,Boulders, Consistency,%Gravel) 0-14" A Loamy Sand IOyr 4/6 14-24" B Loamy Sand I Oyr 7/6 24-120" C Sandy Loam 2.5y 7/4 @42" Stones,Cobbles,Boulders,with Distinct pockets of gravel MINIMUM OF 2 HOLES REQUIRED AT EVERY PROPOSED DISPOSAL AREA Parent Material(geologic): Till . ... ........... ........... Depth to Bedrock: _>120 Depth to Groundwater: 42"_... ......._ Standing Water in Hole: None Weeping from pit face: None., _ Estimated Seasonal High Groundwater: 42" ____,_. . ..._............... .... DEP APPROVED FORM-12/07/95 FORM 11 - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street,North Andover, MA On-site Review Deep Hole Number: 812-3_ _......_.. Date: ._8/9/12......... . .......... Time:- Weather., 90s_5114ny._.._. Location(identify on site plan) ,.,......_. .. Land Use Former_Residence SION Co ..0.-5% Surface._Stones ...None visible ......... .. ... _ Vegetation .__Grass,._Trees,_Shrubs...._._._ . .... ... ..__ Landform ......... _.. Position on landscape(sketch on back) . ._ _._._.. _ Distances from: Open Water Body >100_._..__ feet Drainage way >50 ....._. .. feet Possible Wet Area _ >50 . ... feet Property Line >1,0..... . ...__ feet Drinking Water Well__>1,00feet Other ................ DEEP OBSERVATION HOLE LOG* Depth from Soil Horizon Soil Texture Soil Color Soil Mottling Other Surface(Inches) (USDA) (Munsell) (Structure,Stones,Boulders, Consistency,%Gravel) 0-15" A Loamy Sand l0yr 4/6 15-28" B Loamy Sand l0yr 7/6 28-118" C Sandy Loamy 2.5y 7/4 @42" Cobbles Faint MINIMUM OF 2 HOLES REQUIRED AT EVERY PROPOSED DISPOSAL AREA Parent Material(geologic): .Till ....___.. ............_...._... Depth to Bedrock: _>118"__ Depth to Groundwater: 42".._ _._..... Standing Water in Hole: None .. ........... Weeping from pit face: _None____ Estimated Seasonal High Groundwater: 42" DEP APPROVED FORM-12/07/95 FORM 11 - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street North Andover MA On-site Review Deep Hole Number:.._..81274...... ......... Date: _8/9/12 ............__._...... Time: .._- ................ Weather, 9..0s__Sunny...._.._ ...................................... Location(identify on site plan) Land Use former Residence . .._. Slope__(%) 0,,-5% Surface,_Stones„__None.ysible ....._. Vegetation..._Grass.,..Trees,.Shrubs ..._...... ... .. ....... _. Landform......-, ................ ...... .... Position on landscape(sketch on back).,........, . Distances from: Open Water Body___>100 _..__ .......... feet Drainage way >50....................... feet Possible Wet Area .._>50....._..__................_._._, feet Property Line .................. feet feet Drinking Water Well_,>10,0. feet Other-- DEEP OBSERVATION HOLE LOG* Depth from Soil Horizon Soil Texture Soil Color Soil Mottling Other Surface(Inches) (USDA) (Munsell) (Structure,Stones,Boulders, Consistency,%Gravel) 0-11” A Loamy Sand IOyr 4/6 11-24" B Loamy Sand 1 Oyr 7/6 24-138" C Loamy Sand 2.5y 7/4 @42" Cobbles Distinct MINIMUM OF 2 HOLES REQUIRED AT EVERY PROPOSED DISPOSAL AREA Parent Material(geologic): Till .__„__ . . Depth to Bedrock: >13.8'.'. Depth to Groundwater: 42.'.'.. Standing Water in Hole: None._........._......._......._...,..._._.._.. Weeping from pit face: ,_None._... ............ Estimated Seasonal High Groundwater: 42” ..... _. DEP APPROVED FORM-12/07/95 FORM 11 - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street,North Andover, MA On-site Review Deep Hole Number:-..__1.1.12--1-----_...._.._ Date: _...1-1.42-7.1.29 12............... _Time:_........____.....-......_._ W _.. eather: 30s Cloudy.......__. Location(identify on site plan)..._.............._...__...______.._._._-. ----.........._.__._..__.._.._................._.............. ........._-.-.--------............___._..._._...._..._._..._..---.._.__.__...._._._._._.......___..._.._.._.._..-------_.---._..._._ Land Use _Residential...._......._._.............__.............__._._.._.. Slope(%).. 075% ----------- Surface Stones...-None visible.................._. _ .......................-._...._........ Vegetation....._..._._....._.._ _. Landform __...._. _.._.......- ..__..._...._...__............._._...—............................__...._..- ._......---------__-_._.........--.._._..._...._--.--._-._._........_-......._..._............._..---.... .--........... ._......_........--........--........_ Position on landscape(sketch on back)_..._._..._......_..._..__._._._._. Distances from: Open Water Body.--?.1.09 ..........._......_...... feet Drainage way_ >50 .._._._-_ feet Possible Wet Area >100_....._._.._...-_..._.__ feet Property Line...._>1.0.-_................. feet Drinking Water Well_? FORM 11 - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street,North Andover,MA On-site Review Deep Hole Number:..__1.1.12-2_..._._.._..._.._ Date: ___1.1/27/2012___..____.__........ _._._Time............ .............. Weather: _30s Cloudy___ .. Location(identify on site plan)_ .. Land Use _ResidentiaL__..____._....__._...___...._.___....__....__ Slope(%)_.0-5%._._.__.___......_._ Surface Stones_.._None_visible __.._..._,....__......_____...___.....-.__..__..__..._..... Vegetation.._. -_................ .............................. ........_.. Landform .......___....---.___..__..._.__--_. _._.--_. Position on landscape(sketch on back).._._..- _.-._ Distances from: Open Water Body .>100feet Drainage way .>50 feet Possible Wet Area .>100........._............,__ feet Property Line >10 ._..............- feet Drinking Water Well_ >100_____.._..__. feet Other._....._............. _.___.._ DEEP OBSERVATION HOLE LOG* Depth from Soil Horizon Soil Texture Soil Color Soil Mottling Other Surface(Inches) (USDA) (Munsell) (Structure,Stones,Boulders, Consistency,%Gravel) 0-8" A Loamy Sand 10yr 3/2 8-23" B Loamy Sand 10yr 5/6 23-120" C Loamy Sand 2.5y 8/3 @48"Faint MINIMUM OF 2 HOLES REQUIRED AT EVERY PROPOSED DISPOSAL AREA Parent Material(geologic): Till_....._..._.-__........._.__._.__...._....___.........._.........._.------_.._—. Depth to Bedrock: _>120"..............._ Depth to Groundwater: 4.8'.'.___.___.... Standing Water in Hole: None____ Weeping from pit face: _None Estimated Seasonal High Groundwater: 48"_.._.__ ........... DEP APPROVED FORM-12/07/95 FORM I1 - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street,North Andover, MA On-site Review Deep Hole Number:--J.1.12-3..__...._...-..._.. Date: ..__1.1/27/2012__._.__.___.----- ........_Time__.............._._......_..._........ Weather;.....30s.0 oudy Location(identify on site plan) _. ._._. _ Land Use _Residential_,.__....__..__..__._.__.._..._._....___...___.___ Slope(%).... ...... Surface Stones..__None_visible...._...___._ ........-....................... Vegetation Landform ............._._.-.------....._.._.__.._.__.....----...__..._..-_---..._..._.......__._..._..____...__...._._.__._........._._._....._..........._._......._.................._-........-__....................__._....._...._.................. Position on landscape(sketch on back). _. ,.._ __. Distances from: Open Water Body >100 feet feet Drainage way...>50 _._ feet Possible Wet Area >100__.........._......__ feet Property Line >10__......._.._....___ feet Drinking Water Well.._>10 ...._................. feet Other- -- __._. DEEP OBSERVATION HOLE LOG* Depth from Soil Horizon Soil Texture Soil Color Soil Mottling Other Surface(Inches) (USDA) (Munsell) (Structure,Stones,Boulders, Consistency,%Gravel) 0-8" A Loamy Sand 10yr 3/2 8-16" B Loamy Sand 10yr 5/6 16-120" C Loamy Sand 2.5y 8/3. @42"Faint MINIMUM OF 2 HOLES REQUIRED AT EVERY PROPOSED DISPOSAL AREA Parent Material(geologic): Till.... ..._..._............_.............................___.._..._...__..__.____ Depth to Bedrock: ..>J-2'0 Depth to Groundwater: 4X..'_.................... Standing Water in Hole: None___._..___.__._..____._._.__ Weeping from pit face: ._None____..._._... Estimated Seasonal High Groundwater: 42...._.................... DEP APPROVED FORM-12/07/95 FORM 11 - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street,North Andover, MA On-site Review Deep Hole Number:......1.1.12.-4_......._............. Date: __1.1/27/2012...._...._.__...__... Time.:............__......_._..__._.......... Weather: 30s_Cloudy..............._. Location(identify on site plan) _-. _. Land Use ._Residential-_....................._.............................._....._.... Slope(%) 075.%.-..__._..._...__...__._. Surface Stones None visible_ Vegetation..... _ _-._..-.__.._.__...._....__..._.__.........._.........._............_........_..... _..........................._......_..........._......_......._... ..._..._...._...................__.._._...... .._._...._.__._.._..._...._. Landform Position on landscape(sketch on back).......... Distances from: Open Water Body..._>100..__._._........_ feet Drainage way >50 .......__.. feet Possible Wet Area >100...........,..........._..... feet Property Line >19....................... feet Drinking Water Well >100.................... feet Other..._._....____._...._....._........._._........_. ............... DEEP OBSERVATION HOLE LOG* Depth from Soil Horizon Soil Texture Soil Color Soil Mottling Other Surface(Inches) (USDA) (Munsell) (Structure,Stones,Boulders, Consistency,%Gravel) 0-48" Fill Sand, Silt 48-52" A Loamy Sand 10yr 3/2 52-70" B Loamy Sand 10yr 5/6 70-120" C Loamy Sand 2.5y 8/3 None visible MINIMUM OF 2 HOLES REQUIRED AT EVERY PROPOSED DISPOSAL AREA Parent Material(geologic): Till..__.,.___._._....._.. . . .___,___ ___-_._._.__....._...._____- Depth to Bedrock: ._>120" Depth to Groundwater: >.12.0....'_.......... Standing Water in Hole: None ___... Weeping from pit face: _None___.._..____,__.,. __ - Estimated Seasonal High Groundwater: >120"_ _,_.. ,. .. .__ DEP APPROVED FORM-12/07/95 FORM It - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street,North Andover MA On-site Review Deep Hole Number:....._1.1.3_1................_.._..._. Date: . 1/28/2.013._....._..........._.......... Time:..................................._..............._.......................... Weather:........30s Cloudy....._.._....................... Location(identify on site plan) .......... ............................_........_............... ...................... ..........................__..............................................._.........._......................................... ... _..... . ........ ......... LandUse ._Residential...................._........-...................................._....._,_ Slope(%).__>5%......_..........._._......_..._.. Surface Stones...._None_visible...._._..................._............................................. Vegetation...........__...................................._........................................................._...._.... ............. ... ........... ........._.. .............. Landform ........................_.._......................................_.._...._.__.........._._............_.....__._........_.............._................._...........__._..................................._........._............_..............................._........_....................._......_..............................................-..........................................._......._........................ Position on landscape(sketch on back).,.. ....................................................._...... Distances from: Open Water Body.,>50. feet Drainage way,.>50... .................. feet Possible Wet Area „>50. feet Property Line >10._ ....... ,. feet Drinking Water Well...._....>....1_00_..............._. feet Other................................._.._.............................._........._.......... ...._ DEEP OBSERVATION HOLE LOG* Depth from Soil Horizon Soil Texture Soil Color Soil Mottling Other Surface(Inches) (USDA) (Munsell) (Structure,Stones,Boulders, Consistency,%Gravel) 0-12" A Loamy Sand 10yr 3/2 Frost 12-30" B Loamy Sand 10yr 5/6 30-114" C Sand 2.5y 7/2 @ 72"Distinct Stones and Cobbles MINIMUM OF 2 HOLES REQUIRED AT EVERY PROPOSED DISPOSAL AREA Parent Material(geologic): Till _................... .........._. Depth to Bedrock: >114"......................... _. ..._........ .. Depth to Groundwater: 72'.'... ._.._.... Standing Water in Hole: ._None ...................._,..___„__ Weeping from pit face: None Estimated Seasonal High Groundwater: 72” DEP APPROVED FORM-12/07/95 FORM 11 - SOIL EVALUATOR FORM Location Address or Lot No. 1018 Osgood Street,North Andover, MA On-site Review Deep Hole Number:,_..113-4.__ _._._ Date: _1/28/201,3......... ......... Time: ........ Weather: .30s Cloudy__.. .......... Location(identify on site plan)......._............._._..........._......... .........................._....._._................._......_...._...._..._............................._............_........................................................................_.._.................................._............................................ Land Use ._Residential.... _........ Slope(%) ..>5%...__._................. Surface Stones None visible . _.. Vegetation..........._..............__........_ ............ ................... Landform ._._........__....._..._..........._...... ............. ............................_......................_._................_..............................._......_..._.._..._..............._..........._............. Position on landscape(sketch on back) Distances from: Open Water Body >50 feet Drainage way... >50._._,_.__._._, feet Possible Wet Area .>50 _...... feet Property Line.,>10. ............. feet Drinking Water Well >100 .. feet Other... . DEEP OBSERVATION HOLE LOG* Depth from Soil Horizon Soil Texture Soil Color Soil Mottling Other Surface(Inches) (USDA) (Munsell) (Structure,Stones,Boulders, Consistency,%Gravel) 0-12" Fill Fill Frost/Sandy fill 12-35" A Loamy Sand 10yr 3/2 35-40" B Loamy Sand 10yr 5/6 40-116" C Loamy Sand 2.5y 7/2 @80"Distinct Stone and cobbles MINIMUM OF 2 HOLES REQUIRED AT EVERY PROPOSED DISPOSAL AREA Parent Material (geologic): Till _._..... ... Depth to Bedrock: >116"..._ Depth to Groundwater: 8.0''---..._....... Standing Water in Hole: _None............ Weeping from it face: P g p _.... Estimated Seasonal High Groundwater: 8.0-'.-'.-- DEP APPROVED FORM-12/07/95 MEMORANDUM Date: September 15, 2012 To: Mark Gross, P.E., MHF Design Consultants, Inc. From: Amanda Atwell, CPSS, Michael Howard, CWS, PWS Subject: Wetland Drainage Confirmation, 1018 Osgood Street, North Andover, MA. On March 14, 2012, a wetland/soil scientist from Epsilon Associates, Inc. conducted a field visit to 1018 Osgood Street in North Andover, Massachusetts to delineate wetlands on the subject parcel. Any potential off-site wetlands in the vicinity of the parcel were also assessed and identified. One wetland resource area, referred to as Wetland Series 1, was delineated by Epsilon. This wetland consists of a scrub shrub bordering vegetated wetland ("BVW") and is subject to protection under the Wetlands Protection Act (310 CMR 10.55) and North Andover Bylaw. Refer to Epsilon's March 27, 2012 Wetland Delineation Memo for additional detail. On August 10, 2012, a wetland/soil scientist from Epsilon Associates, Inc. conducted a 2"d field visit to determine if the delineated BVW flows east towards Lake Cochichewick (the Town's surface water drinking supply) or west towards the Merrimack River. As explained in further detail below Epsilon confirmed the BVW flows towards the Merrimack River and is not located in the Lake Cochichewick watershed. Watershed Analysis A large wetland exists along the southern portion of Lawrence Municipal Airport between a small shopping facility and the Casa Blanca Mexican Restaurant. This wetland, in part, flows under the entrance driveway leading to the restaurant and into a pond/wetland located adjacent to Osgood Street. This resource was recently delineated by others using "LEC Resource Area" flagging. A twelve inch wide concrete headwall and corrugated metal pipe was located on the edge of this 2 wetland. Since the direction of flow was not apparent from field observations Epsilon consulted with surveyors from MHF Design Consultants to collect additional data in order to determine if the wetland flows towards Lake Cochichewick via this pipe OR if the pipe directs runoff away from Lake Cochichewick into the wetland before flowing towards the Merrimack River. MHF confirmed the pipe connects to a nearby catch basin located in Osgood Street. The elevation of the aforementioned corrugated metal pipe is lower than the catch basin rim elevation. This indicates that stormwater runoff from Osgood Street flows into the wetland and that the wetland and site drainage do not flow towards Lake Cochichewick. More specifically, water from the wetland / pond flows north to a large wetland complex located west of Commerce Way and north of the industrial park. Although Epsilon did not gain access onto Lawrence Municipal Airport property, use of topographic and aerial mapping allowed tracing of this system that flows into a stream along the northeastern portion of the Airport (near Runway 23 end) and daylights at Holt Road and can be traced along the eastern edge of the landfill. From there previous delineations and prior knowledge of the area (M Howard, Epsilon), as well as topographic/aerial evidence confirms that an unnamed stream flows under the railroad tracks and into the Merrimack River. If you have any questions regarding this report, please do not hesitate to contact me at 978.461.6227 or via email at aatwell@epsilonassociates.com. Thank you. G IProjects21FMgAW AndoverMYQWsgs mxd _ is y Scale 1:24,000 1,00 =00 O 1 inch=2,000 feet Feet Basemap:1987 USGS Quadrangles,MassG1S Sn V.. t �4 AT w.,,i ,r d)i Y' w � f vPon e F r . tlV, § ` J � / 0 REN ff s IA In gIr -41 Osgood 1 d s � � i - kr ✓P k` Ik y^ t"' JILIk qq _ `r SII,I I A. e 1018 Osgood Street, North Andover, MA ® 'Io Figure 2 USGS Locus Map 1016 oV, ALL �4y s� �' brow3 A. a� tv i� 1-b ALI - iNO. Awa -R5 T(Crt C . VAuo. vb"Eum's-z" or- 14e- Et SS a E I LTC f - a est F _ [ P 9 6 - CV 5 r- 44 kvr�v L�4Sr �e t (r- 4 , g e� '� � *T .� APPENDIX B PRE DEVELOPMENT DRAINAGE CALCULATIONS 19 29 10 & 100-YEAR STORM EVENTS F:\Projects\Eng\30531 I\Drainage\Revised 3-25-13\30531 I-Drainage Report--Rev4.doc (2S) RUNOFF TO EASTERN BOUNDARY LINE 1S RUNOFF TO OSGOOD STREET Subcat Reach Pon Link Drainage Diagram for 305312-Predrain--Rev1 Prepared by MHF Design Consultants, Inc, Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC 305312-Predrain--Revl Prepared by MEF Design Consultants, Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Page 2 Area Listing(all nodes) Area CN Description (sq-ft) (subcatchment-numbers) 7,802 70 Woods,Good,HSG C (1S,2S) 20,637 74 >75%Grass cover,Good,HSG C (IS,2S) 893 98 Paved parking,HSG C (IS) 1,383 98 Roofs,HSG C (1S,2S) 30,715 TOTAL AREA 305312-Predrain--Revl Prepared by MHF Design Consultants,Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 C 2010 HydroCAD Software Solutions LLC Page 3 Soil Listing(all nodes) Area Soil Subcatchment (sq-ft) Group Numbers 0 HSG A 0 HSG B 30,715 HSG C 1 S,2S 0 HSG D 0 Other 30,715 TOTAL AREA 305312-Predrain--Revl Type III 24-hr]-year Rainfall=2.50" Prepared by MHF Design Consultants,Inc Printed 12/11/2012 HydroCAD®9 10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Paze 4 Time span=0.00-30.00 hrs,dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method,UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: RUNOFF TO OSGOOD Runoff Area=10,340 sf 17.41%Impervious Runoff Depth=0.74" Flow Length=170' Tc=8.2 min CN=77 Runoff=0.18 cfs 638 cf Subcatchment 2S: RUNOFF TO EASTERN Runoff Area=20,375 sf 2.34%Impervious Runoff Depth=0.57" Flow Length=155' Tc=6.1 min CN=73 Runoff--0.27 cfs 964 cf Total Runoff Area=30,715 sf Runoff Volume=1,602 cf Average Runoff Depth=0.63" 92.59%Pervious=28,439 sf 7.41%Impervious=2,276 sf 305312-Predrain--Revl Type III 24-hr]-year Rainfall=2.50" Prepared by MHF Design Consultants, Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment 1S: RUNOFF TO OSGOOD STREET Runoff = 0.18 cfs @ 12.13 hrs, Volume= 638 cf, Depth= 0.74" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 1-year Rainfall=2.50" Area(sf) CN Description 907 98 Roofs,HSG C 893 98 Paved parking,HSG C 2,333 70 Woods, Good,HSG C 6,207 74 >75%Grass cover,Good,HSG C 10,340 77 Weighted Average 8,540 82.59%Pervious Area 1,800 17.41%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.1 25 0.0300 0.07 Sheet Flow, Woods:Light underbrush n=0.400 P2=3.10" 1.5 80 0.0300 0.87 Shallow Concentrated Flow, Woodland Kv=5.0 fps 0.6 65 0.0700 1.85 Shallow Concentrated Flow, Short Grass Pasture Kv=7.0 fps 8.2 170 Total Summary for Subcatchment 2S: RUNOFF TO EASTERN BOUNDARY LINE Runoff = 0.27 cfs @ 12.10 hrs, Volume= 964 cf, Depth= 0.57" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs, dt=0.01 hrs Type III 24-hr 1-year Rainfall=2.50" Area(sf) CN Description 14,430 74 >75%Grass cover, Good,HSG C 5,469 70 Woods, Good,HSG C 476 98 Roofs HSG C 20,375 73 Weighted Average 19,899 97.66%Pervious Area 476 2.34%Impervious Area 305312-Predrain--Revl Type III24-hr]-year Rainfall=2.50" Prepared by M 4F Design Consultants, Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Pam Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.6 25 0.0600 0.09 Sheet Flow, Woods:Light underbrush n=0.400 P2=3.10" 0.2 15 0.0600 1.22 Shallow Concentrated Flow, Woodland Kv=5.0 fps 0.8 65 0.0400 1.40 Shallow Concentrated Flow, Short Grass Pasture Kv=7.0 fps 0.5 50 0.1000 1.58 Shallow Concentrated Flow, Woodland Kv=5.0 fps 6.1 155 Total 305312-Predrain--Revl Type M24-hr 2-year Rainfall=3.10" Prepared by NMF Design Consultants, Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Page 7 Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method,UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: RUNOFF TO OSGOOD Runoff Area=10,340 sf 17.41%Impervious Runoff Depth=1.14" Flow Length=170' Tc=8.2 min CN=77 Runoff—�0.28 cfs 983 cf Subcatchment 2S: RUNOFF TO EASTERN Runoff Area=20,375 sf 2.34%Impervious Runoff Depth=0.92" Flow Length=155' Tc=6.1 min CN=73 Runoff=0.47 cfs 1,561 cf Total Runoff Area=30,715 sf Runoff Volume=2,544 cf Average Runoff Depth=0.99" 92.59%Pervious=28,439 sf 7.41%Impervious=2,276 sf 305312-Predrain--Revl Type X 24-hr 2-year Rainfall=3.10" Prepared by MEF Design Consultants, Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment 1S: RUNOFF TO OSGOOD STREET Runoff = 0.28 cfs @ 12.12 hrs, Volume= 983 cf, Depth= 1.14" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 2-year Rainfall=3.10" Area(sf) CN Description 907 98 Roofs,HSG C 893 98 Paved parking,HSG C 2,333 70 Woods,Good,HSG C 6,207 74 >75%Grass cover,Good,HSG C 10,340 77 Weighted Average 8,540 82.59%Pervious Area 1,800 17.41%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.1 25 0.0300 0.07 Sheet Flow, Woods: Light underbrush n=0.400 P2=3.10" 1.5 80 0.0300 0.87 Shallow Concentrated Flow, Woodland Kv=5.0 fps 0.6 65 0.0700 1.85 Shallow Concentrated Flow, Short Grass Pasture Kv=7.0 fps 8.2 170 Total Summary for Subcatchment 2S: RUNOFF TO EASTERN BOUNDARY LINE Runoff = 0.47 cfs @ 12.10 hrs, Volume= 1,561 cf, Depth= 0.92" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs, dt=0.01 hrs Type III 24-hr 2-year Rainfall=3.10" Area(sf) CN Description 14,430 74 >75%Grass cover, Good,HSG C 5,469 70 Woods,Good, HSG C 476 98 Roofs HSG C 20,375 73 Weighted Average 19,899 97.66%Pervious Area 476 2.34%Impervious Area 305312-Predrain--Revl Type III24-hr 2-year Rainfall=3.10" Prepared by MHF Design Consultants,Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Pai4e 9 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.6 25 0.0600 0.09 Sheet Flow, Woods: Light underbrush n--0.400 P2=3.10" 0.2 15 0.0600 1.22 Shallow Concentrated Flow, Woodland Kv=5.0 fps 0.8 65 0.0400 1.40 Shallow Concentrated Flow, Short Grass Pasture Kv=7.0 fps 0.5 50 0.1000 1.58 Shallow Concentrated Flow, Woodland Kv=5.0 fps 6.1 155 Total 305312-Predrain--Revl Type X 24-hr 10 year Rainfall=4.50" Prepared by NMF Design Consultants, Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Page 10 Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method,UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: RUNOFF TO OSGOOD Runoff Area=10,340 sf 17.41%Impervious Runoff Depth=2.21" Flow Length=170' Tc=8.2 min CN=77 Runoff-�0.57 cfs 1,905 cf Subcatchment 2S: RUNOFF TO EASTERN Runoff Area=20,375 sf 2.34%Impervious Runoff Depth=1.90" Flow Length=155' Tc=6.1 min CN=73 Runoff--1.02 cfs 3,219 cf Total Runoff Area=30,715 sf Runoff Volume=5,124 cf Average Runoff Depth=2.00" 92.59%Pervious=28,439 sf 7.41%Impervious=2,276 sf 305312-Predrain--Revl Type 11124-hr 10 year Rainfall=4.50" Prepared by MEF Design Consultants,Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Paize 11 Summary for Subcatchment 1S: RUNOFF TO OSGOOD STREET Runoff = 0.57 cfs @ 12.12 hrs, Volume= 1,905 cf, Depth= 2.21" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 10-year Rainfall=4.50" Area(sf) CN Description 907 98 Roofs,HSG C 893 98 Paved parking,HSG C 2,333 70 Woods,Good, HSG C 6,207 74 >75%Grass cover,Good,HSG C 10,340 77 Weighted Average 8,540 82.59%Pervious Area 1,800 17.41%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.1 25 0.0300 0.07 Sheet Flow, Woods:Light underbrush n=0.400 P2=3.10" 1.5 80 0.0300 0.87 Shallow Concentrated Flow, Woodland Kv=5.0 fps 0.6 65 0.0700 1.85 Shallow Concentrated Flow, Short Grass Pasture Kv=7.0 fps 8.2 170 Total Summary for Subcatchment 2S: RUNOFF TO EASTERN BOUNDARY LINE Runoff = 1.02 cfs @ 12.09 hrs, Volume= 3,219 cf, Depth= 1.90" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs, dt=0.01 hrs Type III 24-hr 10-year Rainfall=4.50" Area(sf) CN Description 14,430 74 >75%Grass cover, Good, HSG C 5,469 70 Woods,Good,HSG C 476 98 Roofs HSG C 20,375 73 Weighted Average 19,899 97.66%Pervious Area 476 2.34%Impervious Area 305312-Predrain--Revl Type III24-hr 10 year Rainfall=4.50" Prepared by MEF Design Consultants, Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Paize 12 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.6 25 0.0600 0.09 Sheet Flow, Woods:Light underbrush n=0.400 P2=3.10" 0.2 15 0.0600 1.22 Shallow Concentrated Flow, Woodland Kv=5.0 fps 0.8 65 0.0400 1.40 Shallow Concentrated Flow, Short Grass Pasture Kv=7.0 fps 0.5 50 0.1000 1.58 Shallow Concentrated Flow, Woodland Kv=5.0 fps 6.1 155 Total 305312-Predrain--Revl Type M24-hr 100 year Rainfall=6.40" Prepared by MIF Design Consultants, Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 O 2010 HydroCAD Software Solutions LLC Page 13 Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method,UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: RUNOFF TO OSGOOD Runoff Area=10,340 sf 17.41%Impervious Runoff Depth=3.83" Flow Length=170' Tc=8.2 min CN=77 Runoff=0.99 cfs 3,301 cf Subcatchment 2S: RUNOFF TO EASTERN Runoff Area=20,375 sf 2.34%Impervious Runoff Depth=3.42" Flow Length=155' Tc=6.1 min CN=73 Runoff--1.87 cfs 5,813 cf Total Runoff Area=30,715 sf Runoff Volume=9,113 cf Average Runoff Depth=3.56" 92.59%Pervious=28,439 sf 7.41%Impervious=2,276 sf 305312-Predrain--Revl Type HI 24-hr 100 year Rainfall=6.40" Prepared by MHF Design Consultants, Inc Printed 12/11/2012 HydroCAD®9.10 s/n 01710 ©2010 HydroCAD Software Solutions LLC Page 14 Summary for Subcatchment IS: RUNOFF TO OSGOOD STREET Runoff = 0.99 cfs @ 12.12 hrs, Volume= 3,301 cf, Depth= 3.83" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 100-year Rainfall=6.40" Area(sf) CN Description 907 98 Roofs, HSG C 893 98 Paved parking,HSG C 2,333 70 Woods,Good,HSG C 6,207 74 >75%Grass cover,Good,HSG C 10,340 77 Weighted Average 8,540 82.59%Pervious Area 1,800 17.41%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.1 25 0.0300 0.07 Sheet Flow, Woods:Light underbrush n=0.400 P2=3.10" 1.5 80 0.0300 0.87 Shallow Concentrated Flow, Woodland Kv=5.0 fps 0.6 65 0.0700 1.85 Shallow Concentrated Flow, Short Grass Pasture Kv=7.0 fps 8.2 170 Total Summary for Subcatchment 2S: RUNOFF TO EASTERN BOUNDARY LINE Runoff = 1.87 cfs @ 12.09 hrs, Volume= 5,813 cf, Depth= 3.42" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 100-year Rainfall=6.40" Area(sf) CN Description 14,430 74 >75%Grass cover, Good,HSG C 5,469 70 Woods,Good,HSG C 476 98 Roofs,HSG C 20,375 73 Weighted Average 19,899 97.66%Pervious Area 476 2.34%Impervious Area 305312-Predrain--Revl Type 11124-hr 100 year Rainfall=6.40" Prepared by N HF Design Consultants,Inc Printed 12/11/2012 HydroCAD0 9.10 s/n 01710 02010 HydroCAD Software Solutions LLC Pafze 15 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.6 25 0.0600 0.09 Sheet Flow, Woods:Light underbrush n=0.400 P2=3.10" 0.2 15 0.0600 1.22 Shallow Concentrated Flow, Woodland Kv=5.0 fps 0.8 65 0.0400 1.40 Shallow Concentrated Flow, Short Grass Pasture Kv=7.0 fps 0.5 50 0.1000 1.58 Shallow Concentrated Flow, Woodland Kv=5.0 fps 6.1 155 Total APPENDIX C POST DEVELOPMENT DRAINAGE CALCULATIONS 19 2, 10 & 100-YEAR STORM EVENTS F:\Projects\Eng\30531 I\Drainage\Revised 3-25-13\305311-Drainage Report--Rev4.doc C12S')Z�' RUNOFF TO TRCH 2S DRAIN RUNOFF TO EASTER D BOUNDARY LINE RDP2 ca 'PROP TRENCH DRAIN DESIG POINT#2 1A 3 11S —VA,- PROP DMH-1A D1 RUNOFF TO CB-1 PROP CB-1 PROP DMH-1 2A A DAINF1 PROPrH-2A PROP OIL/WATER PROP UG SEPARATOR#1 INFILTRATION A& SYSTEM-1 ce ce D2 PROP DMH-2 PROP TRENCH DRAIN 13S 4 RUNOFF TO TRENCH DRAIN 4 ®ROOF ROOFtNOFF 01SI RUNOFF TO 0 OOD PRO UG 3S� STREET INF TION SYS EM-2 �� D4 RUNOFF ITRENCH ❑DP1 PROP.UG DETENTION PROP DMH- SYSTEM 17 DESIGN POINT#1 D ^ 3P D PROP TRENCH DRAIN PROP PROP TRENCH DRAIN \14S 2 UNDERGROUND 1 SAND FILTER RUNOFF TO TRENCH DRAIN 2 Subcat Reach Pond Link Routing Diagram for 305312-Postdrain--Rev4 Prepared by MHF Design Consultants, Inc, Printed 3/28/2013 HydroCAD®10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC 305312-Postdrain--Rev4 Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCADV 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paize 2 Area Listing(all nodes) Area CN Description (sq-ft) (subcatchment-numbers) 10,076 74 >75%Grass cover,Good,HSG C (1S,2S,3S, 11S, 13S, 14S) 15,410 98 Paved parking,HSG C (1S,3S, 11S, 12S, 13S, 14S) 1,331 74 Pervious Pavers (3S, 14S) 2,249 98 Roofs,HSG C (ROOF) 1,649 70 Woods,Good,HSG C (2S, 11S) 30,715 88 TOTAL AREA 305312-Postdrain--Rev4 Prepared by MIS Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 3 Soil Listing(all nodes) Area Soil Subcatchment (sq-ft) Group Numbers 0 HSG A 0 HSG B 29,384 HSG C IS,2S,3S, I IS, 12S, 13S, 14S,ROOF 0 HSG D 1,331 Other 3S, 14S 30,715 TOTAL AREA 305312-Postdrain--Rev4 Prepared by N111 F Design Consultants,Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paye 4 Ground Covers (all nodes) HSG-A HSG-B HSG-C HSG-D Other Total Ground Subcatchmeni (sq-ft) (sq-ft) (sq-ft) (sq-ft) (sq-ft) (sq-ft) Cover Numbers 0 0 10,076 0 0 10,076 >75%Grass cover,Good IS, 2S, 3S, 11S 13S > 14S 0 0 15,410 0 0 15,410 Paved parking is, 3S, 11S , 12S 13S > 14S 0 0 0 0 1,331 1,331 Pervious Pavers 3S, 14S 0 0 2,249 0 0 2,249 Roofs RO OF 0 0 1,649 0 0 1,649 Woods,Good 2S, 11S 0 0 29,384 0 1,331 30,715 TOTAL AREA 305312-Postdrain--Rev4 Prepared by NIPIF Design Consultants, Inc Printed 3/28/2013 Hydros AD 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paee 5 Pipe Listing(all nodes) Line# Node In-Invert Out-Invert Length Slope n Diam/Width Height Inside-Fill Number (feet) (feet) (feet) (ft/ft) (inches) (inches) (inches) 1 1 143.03 142.74 58.0 0.0050 0.013 12.0 0.0 0.0 2 3P 137.85 137.80 5.0 0.0100 0.013 12.0 0.0 0.0 3 DI 142.44 142.35 25.0 0.0036 0.013 6.0 0.0 0.0 4 D1 142.69 142.00 30.0 0.0230 0.013 12.0 0.0 0.0 5 D 1 A 142.74 142.50 12.0 0.0200 0.013 12.0 0.0 0.0 6 D2 142.50 142.35 38.0 0.0039 0.013 8.0 0.0 0.0 7 132A 142.35 142.33 3.0 0.0067 0.013 8.0 0.0 0.0 8 D4 137.70 137.00 34.0 0.0206 0.013 12.0 0.0 0.0 9 DET 135.81 135.72 18.0 0.0050 0.013 12.0 0.0 0.0 10 INF 1 142.20 142.10 15.0 0.0067 0.013 12.0 0.0 0.0 11 INF2 144.75 144.65 5.0 0.0200 0.013 6.0 0.0 0.0 12 OWI 142.05 142.00 11.0 0.0045 0.013 8.0 0.0 0.0 13 TDI 140.45 140.35 2.0 0.0500 0.013 6.0 0.0 0.0 14 TD2 140.45 140.35 3.0 0.0333 0.013 6.0 0.0 0.0 15 TD3 145.40 145.35 5.0 0.0100 0.013 6.0 0.0 0.0 16 TD4 142.55 142.50 5.0 0.0100 0.013 8.0 0.0 0.0 305312-Postdrain--ReA Type 11124-hr 2 year Rainfall=3.10" Prepared by MRF Design Consultants, Inc Printed 3/28/2013 HydroCADO 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paye 6 Time span=0.00-30.00 hrs,dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method,UH=SCS Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1S: RUNOFF TO OSGOOD STREET Runoff Area=4,480 sf 29.31%Impervious Runoff Depth=1.39" Tc=5.0 min CN=81 Runoff--O.17 cfs 519 cf Subcatchment 2S: RUNOFF TO EASTERN Runoff Area=3,913 sf 0.00%Impervious Runoff Depth=0.92" Tc=5.0 min CN=73 Runoff--0.09 cfs 300 cf Subcatchment 3S: RUNOFF TO TRENCH DRAIN 1 Runoff Area=4,400 sf 72.11%Impervious Runoff Depth=2.16" Tc=2.0 min CN--91 Runoff--0.29 cfs 794 cf Subcatchment 11S: RUNOFF TO CB-1 Runoff Area=6,861 sf 57.32%Impervious Runoff Depth=1.91" Tc=5.0 min CN=88 Runoff=0.36 cfs 1,091 cf Subcatchment 12S: RUNOFF TO TRENCH Runoff Area=1,200 sf 100.00%Impervious Runoff Depth=2.87" Tc=5.0 min CN=98 Runoff-�0.09 cfs 287 cf Subcatchment 13S: RUNOFF TO TRENCH DRAIN Runoff Area=5,095 sf 89.01%Impervious Runoff Depth=2.55" Tc=5.0 min CN=95 Runoff--0.34 cfs 1,081 cf Subcatchment 14S: RUNOFF TO TRENCH DRAIN Runoff Area=2,517 sf 49.90%Impervious RunoffDepth=1.75" Tc=5.0 min CN=86 Runoff=0.12 cfs 367 cf Subcatchment ROOF: ROOF RUNOFF Runoff Area=2,249 sf 100.00%Impervious Runoff Depth=2.87" Tc=0.0 min CN=98 Runoff-�0.19 cfs 537 cf Reach DPl: DESIGN POINT#1 Inflow=0.22 cfs 1,680 cf Outflow--0.22 cfs 1,680 cf Reach DP2: DESIGN POINT#2 Inflow=0.45 cfs 1,919 cf Outflow--0.45 cfs 1,919 cf Pond 1: PROP CB-1 Peak Elev=143.43' Inflow--0.36 cfs 1,091 cf 12.0" Round Culvert n=0.013 L=58.0' S=0.0050'/' Outflow-0.36 cfs 1,091 cf Pond 3P: PROP UNDERGROUND SAND FILTER Peak Elev=138.22' Inflow=0.40 cfs 1,160 cf 12.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Oufflow=0.40 cfs 1,160 cf Pond Dl: PROP DMH-1 Peak Elev=143.19' Inflow=0.45 cfs 1,377 cf Primary=0.17 cfs 902 cf Secondary=0.34 cfs 475 cf Outflow--0.45 cfs 1,377 cf Pond D1A: PROP DMH-1A Peak Elev=143.22' Inflow=0.45 cfs 1,377 cf 12.0" Round Culvert n=0.013 L=12.0' S=0.0200'/' Outflow--0.45 cfs 1,377 cf Pond D2: PROP DMH-2 Peak Elev=143.21' Inflow=0.34 cfs 1,081 cf 8.0" Round Culvert n=0.013 L=38.0' S=0.0039'/' Outflow=0.34 cfs 1,081 cf Pond D2A: PROP DMH-2A Peak Elev=143.19' Inflow=0.49 cfs 1,983 cf 8.0" Round Culvert n=0.013 L=3.0' S=0.0067'/' Outflow=0.49 cfs 1,983 cf 305312-Postdrain--ReA Type X 24-hr 2-year Rainfall=3.10" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCAD®10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 7 Pond D4: PROP DM11-4 Peak Elev=138.05' Inflow=0.40 cfs 1,160 cf 12.0" Round Culvert n=0.013 L=34.0' S=0.0206'/' Outflow--0.40 cfs 1,160 cf Pond DET:PROP. UG DETENTION SYSTEM Peak Elev=137.98' Storage=328 cf Inflow=0.40 cfs 1,160 cf Outflow=0.12 cfs 1,160 cf Pond INFI: PROP UG INFILTRATION SYSTEM-1 Peak Elev=143.17' Storage--868 cf Inflow--0.79 cfs 2,459 cf Discarded=0.01 cfs 450 cf Primary=0.39 cfs 1,619 cf Outflow--0.40 cfs 2,069 cf Pond INF2: PROP UG INFILTRATION SYSTEM-2 Peak Elev=144.38' Storage--303 cf Inflow=0.19 cfs 537 cf Discarded=0.00 cfs 406 cf Primary=0.00 cfs 0 cf Outflow--0.00 cfs 406 cf Pond OWl: PROP OILIWATER SEPARATOR#1 Peak Elev=143.18' Inflow=0.49 cfs 1,983 cf 8.0" Round Culvert n=0.013 L=11.0' S=0.0045'/' Outflow--0.49 cfs 1,983 cf Pond TDl: PROP TRENCH DRAIN 1 Peak Elev=140.81' Mow--0.29 cfs 794 cf 6.0" Round Culvert n=0.013 L=2.0' S=0.0500'/' Outflow--0.29 cfs 794 cf Pond TD2• PROP TRENCH DRAIN 2 Peak Elev=140.66' Inflow=0.12 cfs 367 cf 6.0" Round Culvert n=0.013 L=3.0' S=0.0333'/' Outflow=0.12 cfs 367 cf Pond TD3• PROP TRENCH DRAIN 3 Peak Elev=145.60' Inflow=0.09 cfs 287 cf 6.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow--0.09 cfs 287 cf Pond TD4: PROP TRENCH DRAIN 4 Peak Elev=143.22' Inflow=0.34 cfs 1,081 cf 8.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow--0.34 cfs 1,081 cf Total Runoff Area=30,715 sf Runoff Volume=4,976 cf Average Runoff Depth=1.94" 42.51%Pervious=13,056 sf 57.49%Impervious= 17,659 sf 305312-Postdrain--Rev4 Type III24-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroC DS 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment 1S: RUNOFF TO OSGOOD STREET Runoff = 0.17 cfs @ 12.08 hrs, Volume= 519 cf, Depth= 1.39" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 2-year Rainfall=3.10" Area(sf) CN Description 3,167 74 >75%Grass cover,Good,HSG C 1,313 98 Paved parking,HSG C 4,480 81 Weighted Average 3,167 70.69%Pervious Area 1,313 29.31%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MPF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment 2S: RUNOFF TO EASTERN BOUNDARY LINE Runoff = 0.09 cfs @ 12.08 hrs, Volume= 300 cf, Depth= 0.92" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs, dt=0.01 hrs Type III 24-hr 2-year Rainfall=3.10" Area(sf) CN Description 2,459 74 >75%Grass cover, Good,HSG C 1,454 70 Woods, Good,HSG C 3,913 73 Weighted Average 3,913 100.00%Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, 305312-Postdrain--Rev4 Type X 24-hr 2-year Rainfall=3.10" Prepared by MIF Design Consultants, Inc Printed 3/28/2013 HydroCAD®10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Pave 10 Summary for Subcatchment 3S: RUNOFF TO TRENCH DRAIN 1 Runoff = 0.29 cfs @ 12.03 hrs, Volume= 794 cf, Depth= 2.16" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 2-year Rainfall=3.10" Area(sf) CN Description 415 74 >75%Grass cover,Good,HSG C * 812 74 Pervious Pavers 3,173 98 Paved parking,HSG C 4,400 91 Weighted Average 1,227 27.89%Pervious Area 3,173 72.11%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.0 Direct Entry, 305312-Postdrain--Rev4 Type M 24-hr 2-year Rainfall=3.10" Prepared by MHF Design Consultants,Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paize 11 Summary for Subcatchment 115: RUNOFF TO CB-1 Runoff = 0.36 cfs @ 12.07 hrs, Volume= 1,091 cf, Depth= 1.91" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs, dt=0.01 hrs Type I1124-hr 2-year Rainfall=3.10" Area(sf) CN Description 2,733 74 >75%Grass cover,Good,HSG C 3,933 98 Paved parking,HSG C 195 70 Woods,Good,HSG C 6,861 88 Weighted Average 2,928 42.68%Pervious Area 3,933 57.32%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, 305312-Postdrain--Rev4 Type X 24-hr 2-year Rainfall=3.10" Prepared by NIHF Design Consultants,Inc Printed 3/28/2013 Hydro a rim 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paize 12 Summary for Subcatchment 125: RUNOFF TO TRENCH DRAIN 3 Runoff = 0.09 cfs @ 12.07 hrs, Volume= 287 cf, Depth= 2.87" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 2-year Rainfall=3.10" Area(sf) CN Description 1,200 98 Paved parking,HSG C 1,200 100.00%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, 305312-Postdrain--Rev4 Type III 24-hr 2-year Rainfall=3.10" Prepared by MIAF Design Consultants,Inc Printed 3/28/2013 HydroCADS 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 13 Summary for Subcatchment 135: RUNOFF TO TRENCH DRAIN 4 Runoff = 0.34 cfs @ 12.07 hrs, Volume= 1,081 cf, Depth= 2.55" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type 111 24-hr 2-year Rainfall=3.10" Area(sf) CN Description 560 74 >75%Grass cover,Good, HSG C 4,535 98 Paved parking,HSG C 5,095 95 Weighted Average 560 10.99%Pervious Area 4,535 89.01%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, 305312-Postdrain--Rev4 Type 11124-hr Z year Rainfall=3.10" Prepared by MBF Design Consultants, Inc Printed 3/28/2013 HydroCADV 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 14 Summary for Subcatchment 145: RUNOFF TO TRENCH DRAIN 2 Runoff = 0.12 cfs @ 12.07 hrs, Volume= 367 cf, Depth= 1.75" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 2-year Rainfall=3.10" Area(sf) CN Description 742 74 >75%Grass cover, Good,HSG C 1,256 98 Paved parking,HSG C * 519 74 Pervious Pavers 2,517 86 Weighted Average 1,261 50.10%Pervious Area 1,256 49.90%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, 305312-Postdrain--ReA Type M24-hr 2-year Rainfall=3.10 Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroC Ann 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Pave 15 Summary for Subcatchment ROOF: ROOF RUNOFF [46] Hint:Tc=O(Instant runoff peak depends on dt) Runoff = 0.19 cfs @ 12.00 hrs, Volume= 537 cf, Depth= 2.87" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-30.00 hrs,dt=0.01 hrs Type III 24-hr 2-year Rainfall=3.10" Area(sf) CN Description 2,249 98 Roofs HSG C 2,249 100.00%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.0 Direct Entry, 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants,Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 O 2012 HydroCAD Software Solutions LLC Pace 16 Summary for Reach DPI: DESIGN POINT #1 [40] Hint:Not Described(Outflow=Inflow) Inflow Area= 13,646 sf, 58.56%Impervious, Inflow Depth= 1.48" for 2-year event Inflow = 0.22 cfs @ 12.09 hrs, Volume= 1,680 cf Outflow = 0.22 cfs @ 12.09 hrs, Volume= 1,680 cf, Atten=0%, Lag=0.0 min Routing by Dyn-Stor-Ind method, Time Span=0.00-30.00 hrs,dt=0.01 hrs 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants,Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 17 Summary for Reach DP2: DESIGN POINT#2 [40]Hint:Not Described(Outflow=Inflow) Inflow Area= 17,069 sf, 56.64%Impervious, Inflow Depth= 1.35" for 2-year event Inflow = 0.45 cfs @ 12.18 hrs, Volume= 1,919 cf Outflow = 0.45 cfs @ 12.18 hrs, Volume= 1,919 cf, Atten=0%, Lag=0.0 min Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs 305312-Postdrain--Rev4 Type I1124-hr 2 year Rainfall=3.10" Prepared by M-IF Design Consultants, Inc Printed 3/28/2013 HydroCAM 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paize 18 Summary for Pond 1: PROP CB-1 Inflow Area= 6,861 sf, 57.32%Impervious, Inflow Depth= 1.91" for 2-year event Inflow = 0.36 cfs @ 12.07 hrs, Volume= 1,091 cf Outflow = 0.36 cfs @ 12.07 hrs, Volume= 1,091 cf, Atten=0%, Lag=0.0 min Primary = 0.36 cfs @ 12.07 hrs, Volume= 1,091 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 143.43'@ 12.09 hrs Flood Elev= 146.30' Device Routing Invert Outlet Devices #1 Primary 143.03' 12.0" Round Culvert L=58.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert=143.03'/ 142.74' S=0.0050'r Cc=0.900 n=0.013 Corrugated PE, smooth interior, Flow Area=0.79 sf Primary OutFlow Max--0.35 cfs @ 12.07 hrs HW=143.42' TW=143.19' (Dynamic Tailwater) t-1=Culvert (Outlet Controls 0.35 cfs @ 1.82 fps) 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MEF Design Consultants, Inc Printed 3/28/2013 HydroCAM 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 19 Summary for Pond 3P: PROP UNDERGROUND SAND FILTER Inflow Area= 6,917 sf, 64.03%Impervious, Inflow Depth= 2.01" for 2-year event Inflow = 0.40 cfs @ 12.04 hrs, Volume= 1,160 cf Outflow = 0.40 cfs @ 12.04 hrs, Volume= 1,160 cf, Atten=0%, Lag=0.0 min Primary = 0.40 cfs @ 12.04 hrs, Volume= 1,160 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs, dt=0.01 hrs Peak Elev=138.22' @ 12.04 hrs Flood Elev= 144.00' Device Routing Invert Outlet Devices #1 Primary 137.85' 12.0" Round Culvert L=5.0' CPP,square edge headwall, Ke=0.500 Inlet/Outlet Invert= 137.85'/137.80' S=0.0100 Y Cc=0.900 n=0.013 Corrugated PE, smooth interior, Flow Area=0.79 sf Primary OutFlow Max--0.40 cfs @ 12.04 hrs HW=138.22' TW=138.04' (Dynamic Tailwater) t--1=Culvert (Barrel Controls 0.40 cfs @ 2.26 fps) 305312-Postdrain--Rev4 Type III 24-hr 2-year Rainfall=3.10" Prepared by NMF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paee 20 Summary for Pond Dl: PROP DMH-1 Inflow Area= 8,061 sf, 63.68%Impervious, Inflow Depth= 2.05" for 2-year event Inflow = 0.45 cfs @ 12.07 hrs, Volume= 1,377 cf Outflow = 0.45 cfs @ 12.07 hrs, Volume= 1,377 cf, Atten=0%, Lag=0.0 min Primary = 0.17 cfs @ 12.03 hrs, Volume= 902 cf Secondary= 0.34 cfs @ 12.09 hrs, Volume= 475 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 143.19'@ 12.20 hrs Flood Elev= 146.42' Device Routing Invert Outlet Devices #1 Primary 142.44' 6.0" Round Culvert L=25.0' CPP,square edge headwall, Ke=0.500 Inlet/Outlet Invert= 142.44'/ 142.35' S=0.0036? Cc=0.900 n=0.013 Cast iron, coated, Flow Area=0.20 sf 42 Secondary 142.69' 12.0" Round Culvert L=30.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert- 142.69'/ 142.00' S=0.0230? Cc=0.900 n=0.013 Corrugated PE,smooth interior, Flow Area=0.79 sf rimary OutFlow Max=0.11 cfs @ 12.03 hrs HW=142.98' TW=142.96' (Dynamic Tailwater) 1=Culvert (Outlet Controls 0.11 cfs @ 0.64 fps) econdary OutFlow Max--0.29 cfs @ 12.09 hrs HW=143.12' TW=143.04' (Dynamic Tailwater) 2=Culvert (Outlet Controls 0.29 cfs @ 1.33 fps) 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants,Inc Printed 3/28/2013 HydroCAM 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 21 Summary for Pond DIA: PROP DMH-1A Inflow Area= 8,061 sf, 63.68%Impervious, Inflow Depth= 2.05" for 2-year event Inflow = 0.45 cfs @ 12.07 hrs, Volume= 1,377 cf Outflow = 0.45 cfs @ 12.07 hrs, Volume= 1,377 cf, Atten=0%, Lag=0.0 min Primary = 0.45 cfs @ 12.07 hrs, Volume= 1,377 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 143.22'@ 12.16 hrs Flood Elev= 147.50' Device Routing Invert Outlet Devices #1 Primary 142.74' 12.0" Round Culvert L= 12.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert=142.74'/ 142.50' S=0.0200'/' Cc=0.900 n--0.013 Corrugated PE, smooth interior, Flow Area=0.79 sf Primary OutFlow Max=0.41 cfs @ 12.07 hrs HW=143.19' TW=143.09' (Dynamic Tailwater) L1=Culvert (Outlet Controls 0.41 cfs @ 1.76 fps) 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCaD9 10.00 s/„01710 n 2012 HydroCAD Software Solutions LLC Page 22 Summary for Pond D2: PROP DMH-2 [80] Warning:Exceeded Pond TD4 by 0.05' @ 24.16 hrs(0.01 cfs 5 co Inflow Area= 5,095 sf, 89.01%Impervious, Inflow Depth= 2.55" for 2-year event Inflow = 0.34 cfs @ 12.07 hrs, Volume= 1,081 cf Outflow = 0.34 cfs @ 12.07 hrs, Volume= 1,081 cf, Atten=0%, Lag=0.0 min Primary = 0.34 cfs @ 12.07 hrs, Volume= 1,081 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 143.21'@ 12.18 hrs Flood Elev= 145.00' Device Routing Invert Outlet Devices 41 Primary 142.50' 8.0" Round Culvert L=38.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert= 142.50'/ 142.35' S=0.0039'/' Cc=0.900 n=0.013 Cast iron, coated, Flow Area=0.35 sf Primary OutFlow Max--0.29 cfs @ 12.07 hrs HW=143.14' TW=143.09' (Dynamic Tailwater) L1=Culvert (Outlet Controls 0.29 cfs @ 1.07 fps) 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by Ml IF Design Consultants,Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 23 Summary for Pond D2A: PROP DMH-2A [80] Warning:Exceeded Pond D1 by 0.17'@ 24.15 hrs(0.05 cfs 91 cf) [80] Waming: Exceeded Pond D2 by 0.11'@ 24.31 hrs(0.02 cfs 15 cf) Inflow Area= 13,156 sf, 73.49%Impervious, Inflow Depth= 1.81" for 2-year event Inflow = 0.49 cfs @ 12.05 hrs, Volume= 1,983 cf Outflow = 0.49 cfs @ 12.05 hrs, Volume= 1,983 cf, Atten=0%, Lag=0.0 min Primary = 0.49 cfs @ 12.05 hrs, Volume= 1,983 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs, dt=0.01 hrs Peak Elev= 143.19'@ 12.19 hrs Flood Elev= 146.00' Device Routing Invert Outlet Devices #1 Primary 142.35' 8.0" Round Culvert L=3.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert= 142.35'/142.33' S=0.0067'/' Cc=0.900 n=0.013 Cast iron,coated, Flow Area=0.35 sf Primary OutFlow Max--0.40 cfs @ 12.05 hrs HW=143.03' TW=142.98' (Dynamic Tailwater) L1=Culvert (Inlet Controls 0.40 cfs @ 1.13 fps) 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by NMF Design Consultants, Inc Printed 3/28/2013 HydroCAM 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paye 24 Summary for Pond D4: PROP DMI-4 Inflow Area= 9,166 sf, 72.86%Impervious, Inflow Depth= 1.52" for 2-year event Inflow = 0.40 cfs @ 12.04 hrs, Volume= 1,160 cf Outflow = 0.40 cfs @ 12.04 hrs, Volume= 1,160 cf, Atten=0%, Lag=0.0 min Primary = 0.40 cfs @ 12.04 hrs, Volume= 1,160 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 138.05'@ 12.07 hrs Flood Elev= 144.50' Device Routing Invert Outlet Devices #1 Primary 137.70' 12.0" Round Culvert L=34.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert=137.70'/ 137.00' S=0.0206? Cc=0.900 n=0.013 Corrugated PE, smooth interior, Flow Area—0.79 sf Primary OutFlow Max--0.38 cfs @ 12.04 hrs HW=138.04' TW=137.71' (Dynamic Tailwater) L1=Culvert (Outlet Controls 0.38 cfs @ 2.41 fps) 305312-Postdrain--Rev4 TypeI1124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 25 Summary for Pond DET: PROP. UG DETENTION SYSTEM Inflow Area= 9,166 sf, 72.86%Impervious, Inflow Depth= 1.52" for 2-year event Inflow = 0.40 cfs @ 12.04 firs, Volume= 1,160 cf Outflow = 0.12 cfs @ 12.34 hrs, Volume= 1,160 cf, Atten=69%, Lag= 18.4 min Primary = 0.12 cfs @ 12.34 hrs, Volume= 1,160 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 137.98'@ 12.34 hrs Surf.Area=977 sf Storage=328 cf Flood Elev= 139.00' Surf.Area=957 sf Storage=827 cf Plug-Flow detention time=37.5 min calculated for 1,160 cf(100%of inflow) Center-of-Mass det.time=37.5 min(844.8-807.2) Volume Invert Avail.Storage Storage Description #IA 137.00' 0 cf 14.351W x 66.66'L x 2.67'H Field A 2,551 cf Overall- 1,046 cf Embedded= 1,505 cf x 0.0%Voids #2A 137.00' 827 cf ADS N-12 24 x 16 Inside 91 Inside=23.8"W x 23.8"H=>3.10 sf x 20.001=62.0 cf Outside=28.0"W x 28.0"H=>3.92 sf x 20.001=78.4 cf Row Length Adjustment=-19.67'x 3.10 sf x 4 rows 12.68'Header x 3.10 sf x 2=78.6 cf Inside 93 137.00' 31 cf 24.0" D x 10.0'L Pipe Storage 858 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routing Invert Outlet Devices #1 Primary 135.81' 12.0" Round Culvert L= 18.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert=135.81'/135.72' S=0.0050'/' Cc=0.900 n--0.013 Corrugated PE,smooth interior, Flow Area=0.79 sf #2 Device 1 137.00' 1.5"Vert. Orifice/Grate C=0.600 #3 Device 1 137.80' 4.0"Vert. Orifice/Grate C=0.600 #4 Device 1 138.95' 12.0" Horiz. Orifice/Grate C=0.600 Limited to weir flow at low heads Primary OutFlow Max=0.12 cfs @ 12.34 hrs HW=137.98' TW=0.00' (Dynamic Tailwater) t-1=Culvert (Passes 0.12 cfs of 4.88 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.06 cfs @ 4.60 fps) 3=Orifice/Grate (Orifice Controls 0.07 cfs @ 1.43 fps) -4--Orifice/Grate (Controls 0.00 cfs) 305312-Postdrain--Rev4 Type III 24-hr 2-year Rainfall=3.10" Prepared by MEF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 26 Pond DET: PROP. UG DETENTION SYSTEM - Chamber Wizard Field A Chamber Model=ADS N-12 24 Inside=23.8"W x 23.8"H=>3.10 sf x 20.001=62.0 cf Outside=28.0"W x 28.0"H=>3.92 sf x 20.001=78.4 cf Row Length Adjustment=-19.67'x 3.10 sf x 4 rows 28.0" Wide+13.4" Spacing=41.4" C-C Row Spacing 4 Chambers/Row x 20.00'Long-19.67'Row Adjustment+2.33'Header x 2=65.00'Row Length+10.0"End Stone x 2=66.66'Base Length 4 Rows x 28.0" Wide+ 13.4" Spacing x 3 + 10.0" Side Stone x 2= 14.35'Base Width 28.0" Chamber Height+4.0" Cover=2.67'Field Height 16 Chambers x 62.0 cf -19.67'Row Adjustment x 3.10 sf x 4 Rows+ 12.68'Header x 3.10 sf x 2=826.7 cf Chamber Storage 16 Chambers x 78.4 cf -19.67'Row Adjustment x 3.92 sf x 4 Rows+ 12.68'Header x 3.92 sf x 2= 1,045.3 cf Displacement 2,551.1 cf Field- 1,045.3 cf Chambers= 1,505.8 cf Stone x 0.0%Voids=0.0 cf Stone Storage Chamber Storage+Stone Storage=826.7 cf=0.019 of Overall Storage Efficiency=32.4% 16 Chambers 94.5 cy Field 55.8 cy Stone 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCAD®10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paize 27 Summary for Pond INFI: PROP UG INFILTRATION SYSTEM-1 [80] Warning:Exceeded Pond OW1 by 0.58' @ 24.13 hrs(0.61 cfs 3,620 cf) Inflow Area= 13,156 sf, 73.49%Impervious, Inflow Depth= 2.24" for 2-year event Inflow = 0.79 cfs @ 12.07 hrs, Volume= 2,459 cf Outflow = 0.40 cfs @ 12.20 hrs, Volume= 2,069 cf, Atten=50%, Lag=7.8 min Discarded = 0.01 cfs @ 12.20 hrs, Volume= 450 cf Primary = 0.39 cfs @ 12.20 hrs, Volume= 1,619 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 143.17'@ 12.20 hrs Surf.Area= 1,087 sf Storage=868 cf Flood Elev= 143.84' Surf.Area= 1,087 sf Storage= 1,168 cf Plug-Flow detention time=(not calculated: outflow precedes inflow) Center-of-Mass det.time=93.4 min(886.7-793.4) Volume Invert Avail.Storage Storage Description #lA 141.67' 700 cf 31.98'W x 34.00'L x 2.17'H Field A 2,355 cf Overall-607 cf Embedded= 1,749 cf x 40.0%Voids #2A 142.00' 456 cf ADS N-12 15 x 12 Inside 91 Inside= 14.8"W x 14.8"H=> 1.20 sf x 20.001=24.0 cf Outside= 18.0"W x 18.0"H=> 1.60 sf x 20.001=31.9 cf Row Length Adjustment=+7.00'x 1.20 sf x 12 rows 27.98' Header x 1.20 sf x 2=67.2 cf Inside #3 142.00' 12 cf 15.0" D x 10.0'L Pipe Storage -Impervious 1,168 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routing Invert Outlet Devices 91 Discarded 141.67' 0.200 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation=0.00' #2 Primary 142.20' 12.0" Round Culvert L= 15.0' CPP,square edge headwall, Ke=0.500 Inlet/Outlet Invert-142.20'/ 142.10' S=0.0067'/' Cc=0.900 n--0.013 Corrugated PE, smooth interior, Flow Area=0.79 sf #3 Device 2 142.60' 4.5" Vert.Orifice/Grate C=0.600 #4 Device 2 143.00' 4.5" Vert. Orifice/Grate C=0.600 #5 Device 2 143.65' 12.0" Horiz. Orifice/Grate C=0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.01 cfs @ 12.20 hrs HW=143.17' (Free Discharge) L1=Exfiltration (Controls 0.01 cfs) Primary OutFlow Max--0.39 cfs @ 12.20 hrs HW=143.17' TW=0.00' (Dynamic Tailwater) t-2=Culvert (Passes 0.39 cfs of 2.09 cfs potential flow) A. 3=Orifice/Grate (Orifice Controls 0.33 cfs @ 2.97 fps) 4=Orifice/Grate (Orifice Controls 0.07 cfs @ 1.39 fps) =Orifice/Grate (Controls 0.00 cfs) 305312-Postdrain--Rev4 Type X 24-hr 2-year Rainfall=3.10" Prepared by MEF Design Consultants,Inc Printed 3/28/2013 HydroCADO 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 28 Pond INFI: PROP UG INFILTRATION SYSTEM-1 - Chamber Wizard Field A Chamber Model=ADS N-12 15 Inside= 14.8"W x 14.8"H=> 1.20 sf x 20.00'L=24.0 cf Outside= 18.0"W x 18.0"H=> 1.60 sf x 20.001=31.9 cf Row Length Adjustment=+7.00'x 1.20 sf x 12 rows 18.0" Wide+ 10.9" Spacing=28.9" C-C Row Spacing 1 Chambers/Row x 20.00'Long+7.00'Row Adjustment+1.50'Header x 2=30.00'Row Length+24.0"End Stone x 2 =34.00'Base Length 12 Rows x 18.0" Wide+ 10.9" Spacing x 11 +24.0" Side Stone x 2=31.98'Base Width 4.0" Base+ 18.0" Chamber Height+4.0" Cover=2.17'Field Height 12 Chambers x 24.0 cf +7.00'Row Adjustment x 1.20 sf x 12 Rows+27.98'Header x 1.20 sf x 2=456.0 cf Chamber Storage 12 Chambers x 31.9 cf +7.00'Row Adjustment x 1.60 sf x 12 Rows+27.98'Header x 1.60 sf x 2=606.3 cf Displacement 2,355.5 cf Field-606.3 cf Chambers= 1,749.2 cf Stone x 40.0%Voids=699.7 cf Stone Storage Chamber Storage+Stone Storage= 1,155.6 cf=0.027 of Overall Storage Efficiency=49.1% 12 Chambers 87.2 cy Field 64.8 cy Stone 305312-Postdrain--Rev4 Type II124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants,Inc Printed 3/28/2013 HydroC D 10.00 s/n 01710 n 2012 HydroCAD Software Solutions LLC Paize 29 Summary for Pond INF2: PROP UG INFILTRATION SYSTEM-2 Inflow Area= 2,249 sf,100.00%Impervious, Inflow Depth= 2.87" for 2-year event Inflow = 0.19 cfs @ 12.00 hrs, Volume= 537 cf Outflow = 0.00 cfs @ 15.71 hrs, Volume= 406 cf, Atten=98%, Lag=222.8 min Discarded = 0.00 cfs @ 15.71 hrs, Volume= 406 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 144.38' @ 15.71 hrs Surf.Area= 1,011 sf Storage=303 cf Flood Elev= 145.84' Surf.Area= 1,006 sf Storage= 1,073 cf Plug-Flow detention time=(not calculated:outflow precedes inflow) Center-of-Mass det. time=322.3 min( 1,073.8-751.5 ) Volume Invert Avail Storage Storage Description #IA 143.67' 649 cf 29.58'W x 34.00'L x 2.17'H Field A 2,178 cf Overall-556 cf Embedded= 1,622 cf x 40.0%Voids #2A 144.00' 418 cf ADS N-12 15 x 11 Inside#1 Inside= 14.8"W x 14.8"H=> 1.20 sf x 20.001=24.0 cf Outside= 18.0"W x 18.0"H=> 1.60 sf x 20.001=31.9 cf Row Length Adjustment=+7.00'x 1.20 sf x 11 rows 25.58'Header x 1.20 sf x 2=61.4 cf Inside #3 144.00' 6 cf 15.0" D x 5.0'L Pipe Storage 1,073 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routing Invert Outlet Devices #1 Primary 144.75' 6.0" Round Culvert L=5.0' CPP, square edge headwall, Ke--0.500 Inlet/Outlet Invert=144.75'/ 144.65' S=0.0200 Y Cc=0.900 n--0.013 Corrugated PE, smooth interior, Flow Area=0.20 sf #2 Discarded 143.67' 0.200 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation=0.00' Discarded OutFlow Max--0.00 cfs @ 15.71 hrs HW=14438' (Free Discharge) L2=Exfiltration (Controls 0.00 cfs) Primary OutFlow Max--0.00 cfs @ 0.00 hrs HW=143.67' TW=137.70' (Dynamic Tailwater) t-1=Culvert (Controls 0.00 cfs) 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by NII-IF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 C 2012 HydroCAD Software Solutions LLC Page 30 Pond INF2: PROP UG INFILTRATION SYSTEM-2 - Chamber Wizard Field A Chamber Model=ADS N-12 15 Inside= 14.8"W x 14.8"H=> 1.20 sf x 20.00'L=24.0 cf Outside= 18.0"W x 18.0"H=> 1.60 sf x 20.00'L=31.9 cf Row Length Adjustment=+7.00'x 1.20 sf x 11 rows 18.0" Wide+ 10.9" Spacing=28.9" C-C Row Spacing 1 Chambers/Row x 20.00'Long+7.00'Row Adjustment+1.50'Header x 2=30.00'Row Length+24.0"End Stone x 2 =34.00'Base Length 11 Rows x 18.0" Wide+ 10.9" Spacing x 10+24.0" Side Stone x 2=29.58'Base Width 4.0"Base+ 18.0" Chamber Height+4.0" Cover=2.17'Field Height 11 Chambers x 24.0 cf +7.00'Row Adjustment x 1.20 sf x 11 Rows+25.58'Header x 1.20 sf x 2=417.8 cf Chamber Storage 11 Chambers x 31.9 cf +7.00'Row Adjustment x 1.60 sf x 11 Rows+25.58'Header x 1.60 sf x 2=555.5 cf Displacement 2,178.2 cf Field- 555.5 cf Chambers= 1,622.7 cf Stone x 40.0%Voids=649.1 cf Stone Storage Chamber Storage+Stone Storage= 1,066.8 cf=0.024 of Overall Storage Efficiency=49.0% 11 Chambers 80.7 cy Field 60.1 cy Stone 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paize 31 Summary for Pond OWl: PROP OIL/WATER SEPARATOR#1 [80] Warning: Exceeded Pond D2A by 0.26' @ 24.20 hrs(0.15 cfs 984 cf) Inflow Area= 13,156 sf, 73.49%Impervious, Inflow Depth= 1.81" for 2-year event Inflow = 0.49 cfs @ 12.05 hrs, Volume= 1,983 cf Outflow = 0.49 cfs @ 12.05 hrs, Volume= 1,983 cf, Atten=0%, Lag=0.0 min Primary = 0.49 cfs @ 12.05 hrs, Volume= 1,983 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs, dt=0.01 hrs Peak Elev= 143.18'@ 12.20 hrs Flood Elev=146.36' Device Routing Invert Outlet Devices #1 Primary 142.05' 8.0" Round Culvert L= 11.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert— 142.05'/ 142.00' S=0.0045 T Cc=0.900 n=0.013 Corrugated PE, smooth interior, Flow Area=0.35 sf Primary OutFlow Max=0.40 cfs @ 12.05 hrs HW=142.98' TW=142.92' (Dynamic Tailwater) L1=Culvert (Inlet Controls 0.40 cfs @ 1.14 fps) 305312-Postdrain--Rev4 Type III24-hr 2 year Rainfall=3.10" Prepared by MI-IF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paize 32 Summary for Pond TDI: PROP TRENCH DRAIN 1 Inflow Area= 4,400 sf, 72.11%Impervious, Inflow Depth= 2.16" for 2-year event Inflow = 0.29 cfs @ 12.03 hrs, Volume= 794 cf Outflow = 0.29 cfs @ 12.03 hrs, Volume= 794 cf, Atten=0%, Lag=0.0 min Primary = 0.29 cfs @ 12.03 hrs, Volume= 794 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 140.81'@ 12.03 hrs Flood Elev= 141.45' Device Routing Invert Outlet Devices #1 Primary 140.45' 6.0" Round Culvert L=2.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert=140.45'/ 140.35' S=0.0500'/' Cc=0.900 n--0.013 Cast iron, coated, Flow Area=0.20 sf Primary OutFlow Max=0.29 cfs @ 12.03 hrs HW=140.81' TW=138.22' (Dynamic Tailwater) L-1=Culvert (Barrel Controls 0.29 cfs @ 2.72 fps) 305312-Postdrain--Rev4 Type III 24-hr 2-year Rainfall=3.10" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroC M 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paee 33 Summary for Pond TD2: PROP TRENCH DRAIN 2 Inflow Area= 2,517 sf, 49.90%Impervious, Inflow Depth= 1.75" for 2-year event Inflow = 0.12 cfs @ 12.07 hrs, Volume— 367 cf Outflow = 0.12 cfs @ 12.07 hrs, Volume= 367 cf, Atten=0%, Lag=0.0 min Primary = 0.12 cfs @ 12.07 hrs, Volume= 367 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs, dt=0.01 hrs Peak Elev= 140.66'@ 12.07 hrs Flood Elev= 142.74' Device Routing Invert Outlet Devices #1 Primary 140.45' 6.0" Round Culvert L=3.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert=140.45'/ 140.35' S=0.0333 '/' Cc=0.900 n=0.013 Cast iron, coated, Flow Area=0.20 sf Primary Outflow Max--O.12 cfs @ 12.07 hrs HW=140.66' TW=138.20' (Dynamic Tailwater) t-1=Culvert (Barrel Controls 0.12 cfs @ 2.29 fps) 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 34 Summary for Pond TD3: PROP TRENCH DRAIN 3 Inflow Area= 1,200 sf,100.00%Impervious, Inflow Depth= 2.87" for 2-year event Inflow = 0.09 cfs @ 12.07 hrs, Volume= 287 cf Outflow = 0.09 cfs @ 12.07 hrs, Volume= 287 cf, Atten=0%, Lag=0.0 min Primary = 0.09 cfs @ 12.07 hrs, Volume= 287 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 145.60' @ 12.07 hrs Flood Elev= 146.90' Device Routing Invert Outlet Devices #1 Primary 145.40' 6.0" Round Culvert L=5.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert=145.40'/ 145.35' S=0.0100'/' Cc=0.900 n=0.013 Cast iron,coated, Flow Area=0.20 sf Primary OutFlow Max=0.09 cfs @ 12.07 hrs HW=145.60' TW=143.18' (Dynamic Tailwater) L1=Culvert (Barrel Controls 0.09 cfs @ 1.73 fps) 305312-Postdrain--Rev4 Type 11124-hr 2 year Rainfall=3.10" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 35 Summary for Pond TD4: PROP TRENCH DRAIN 4 Inflow Area= 5,095 sf, 89.01%Impervious, Inflow Depth= 2.55" for 2-year event Inflow = 0.34 cfs @ 12.07 hrs, Volume= 1,081 cf Outflow = 0.34 cfs @ 12.07 hrs, Volume= 1,081 cf, Atten=0%, Lag=0.0 min Primary = 0.34 cfs @ 12.07 hrs, Volume= 1,081 cf Routing by Dyn-Stor-Ind method,Time Span=0.00-30.00 hrs,dt=0.01 hrs Peak Elev= 143.22'@ 12.15 hrs Flood Elev= 144.50' Device Routing Invert Outlet Devices #1 Primary 142.55' 8.0" Round Culvert L=5.0' CPP, square edge headwall, Ke=0.500 Inlet/Outlet Invert—142.55'/142.50' S=0.0100'/' Cc=0.900 n=0.013 Cast iron,coated, Flow Area=0.35 sf Primary OutFlow Max--0.25 cfs @ 12.07 hrs HW=143.17' TW=143.14' (Dynamic Tailwater) t-1=Culvert (Outlet Controls 0.25 cfs @ 0.97 fps) 12S RUNOFF TO TRE CH 2S DRAIN ARUNOFF TO EASTER BOUNDARY LINE [DP]2 °B PROP TRENCH DRAIN DESIG OINT#2 1A 3 15 1 PROP DMH71A AD1 __ RUNOFF TO CB-1 PROP CB-1 PROP DMH-1 \Be \ � OW1 Q INF1 PROPrH-2A PROP OIL/WATER PROP UG SEPARATOR#1 INFILTRATION SYSTEM-1 ce ca D2 D PROP DMH-2 PROP TRENCHDRAIN (\13S 4 V RUNOFF TO TRENCH DRAIN 4 ROOF/ ROOFtNOFF 01SINF2 RUNOFF TOOOOD PRO UG 35 STREET INFIL TION SYS EM-2 Ce RUNOFF T D TRENCH / EX n D4 DR IN 1 DP1 4 PROP.UG DETENTION PROP DMH�\ - ❑ SYSTEM DESIGN POINT#1 D D 14S TRENCH DRAIN PROP PROP TRENCH DRAIN 2 UNDERGROUND 1 SAND FILTER RUNOFF TO TRENCH DRAIN 2 SubCat Reach Pon Link Routing Diagram for 305312-Postdrain--Rev4 Prepared by MHF Design Consultants, Inc, Printed 3/28/2013 HydroCAD®10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC 305312-Postdrain--Rev4 Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCAM 10.00 s/n 01710 C 2012 HydroCAD Software Solutions LLC Paize 2 Pipe Listing(all nodes) Line# Node In-Invert Out-Invert Length Slope n Diam/Width Height Inside-Fill Number (feet) (feet) (feet) (ft/ft) (inches) (inches) (inches) 1 1 143.03 142.74 58.0 0.0050 0.013 12.0 0.0 0.0 2 3P 137.85 137.80 5.0 0.0100 0.013 12.0 0.0 0.0 3 D1 142.44 142.35 25.0 0.0036 0.013 6.0 0.0 0.0 4 D1 142.69 142.00 30.0 0.0230 0.013 12.0 0.0 0.0 5 D 1 A 142.74 142.50 12.0 0.0200 0.013 12.0 0.0 0.0 6 D2 142.50 142.35 38.0 0.0039 0.013 8.0 0.0 0.0 7 132A 142.35 142.33 3.0 0.0067 0.013 8.0 0.0 0.0 8 D4 137.70 137.00 34.0 0.0206 0.013 12.0 0.0 0.0 9 DET 135.81 135.72 18.0 0.0050 0.013 12.0 0.0 0.0 10 INF 1 142.20 142.10 15.0 0.0067 0.013 12.0 0.0 0.0 11 INF2 144.75 144.65 5.0 0.0200 0.013 6.0 0.0 0.0 12 OW1 142.05 142.00 11.0 0.0045 0.013 8.0 0.0 0.0 13 TDI 140.45 140.35 2.0 0.0500 0.013 6.0 0.0 0.0 14 TD2 140.45 140.35 3.0 0.0333 0.013 6.0 0.0 0.0 15 TD3 145.40 145.35 5.0 0.0100 0.013 6.0 0.0 0.0 16 TD4 142.55 142.50 5.0 0.0100 0.013 8.0 0.0 0.0 305312-Postdrain--ReA Type 11124-hr ]-year Rainfall=2.50" Prepared by MHF Design Consultants, Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 3 Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method,UH=SCS Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1S: RUNOFF TO OSGOOD STREET Runoff Area=4,480 sf 29.31%Impervious Runoff Depth=0.94" Tc=5.0 min CN=81 Runoff-�O.I I cfs 352 cf Subcatchment 2S: RUNOFF TO EASTERN Runoff Area=3,913 sf 0.00%Impervious Runoff Depth=0.57" Tc=5.0 min CN=73 Runoff=0.05 cfs 185 cf Subcatchment 3S: RUNOFF TO TRENCH DRAIN 1 Runoff Area=4,400 sf 72.11%Impervious RunoffDepth=1.61" Tc=2.0 min CN=91 Runoff--0.22 cfs 590 cf Subcatchment 11S: RUNOFF TO CB-1 Runoff Area=6,861 sf 57.32%Impervious RunoffDepth=1.38" Tc=5.0 min CN=88 Runoff--0.26 cfs 790 cf Subcatchment 12S: RUNOFF TO TRENCH Runoff Area=1,200 sf 100.00%Impervious Runoff Depth=2.27" Tc=5.0 min CN=98 Runoff=0.07 cfs 227 cf Subcatchment 13S: RUNOFF TO TRENCH DRAIN Runoff Area=5,095 sf 89.01%Impervious Runoff Depth=1.96" Tc=5.0 min CN=95 Runoff=0.27 cfs 834 cf Subcatchment 14S: RUNOFF TO TRENCH DRAIN Runoff Area=2,517 sf 49.90%Impervious Runoff Depth=1.24" Tc=5.0 min CN=86 Runoff0.09 cfs 261 cf Subcatchment ROOF: ROOF RUNOFF Runoff Area=2,249 sf 100.00%Impervious Runoff Depth=2.27" Tc=0.0 min CN=98 Runoff--0.15 cfs 426 cf Reach DPI: DESIGN POINT#1 Inflow=0.16 cfs 1,203 cf Outflow=0.16 cfs 1,203 cf Reach DP2: DESIGN POINT#2 Inflow=0.24 cfs 1,218 cf Outflow--0.24 cfs 1,218 cf Pond 1: PROP CB-1 Peak Elev=143.35' Inflow=0.26 cfs 790 cf 12.0" Round Culvert n=0.013 L=58.0' S=0.0050'/' Outflow--0.26 cfs 790 cf Pond 3P: PROP UNDERGROUND SAND FILTER Peak Elev=138.16' Inflow--0.29 cfs 851 cf 12.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow--0.29 cfs 851 cf Pond Dl: PROP DMH-1 Peak Elev=142.97' Inflow=0.33 cfs 1,017 cf Primary=0.18 cfs 805 cf Secondary=0.15 cfs 212 cf Outflow--0.33 cfs 1,017 cf Pond D1A: PROP DMH-1A Peak Elev=143.07' Inflow--0.33 cfs 1,017 cf 12.0" Round Culvert n=0.013 L=12.0' S=0.0200'/' Outflow=0.33 cfs 1,017 cf Pond D2: PROP DMH-2 Peak Elev=142.98' Inflow--0.27 cfs 834 cf 8.0" Round Culvert n=0.013 L=38.0' S=0.0039'r Outflow=0.27 cfs 834 cf Pond D2A: PROP DMH-2A Peak Elev=142.97' Inflow=0.45 cfs 1,639 cf 8.0" Round Culvert n=0.013 L=3.0' S=0.0067'/' Outflow--0.45 cfs 1,639 cf 305312-Postdrain--ReA Type11124-hr ]-year Rainfall=2.50" Prepared by MFF Design Consultants, Inc Printed 3/28/2013 HydroCADO 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 4 Pond D4• PROP DMH-4 Peak Elev=137.97' Inflow=0.29 cfs 851 cf • 12.0" Round Culvert n=0.013 L=34.0' S=0.0206'/' Outflow--0.29 cfs 851 cf Pond DET: PROP.UG DETENTION SYSTEM Peak Elev=137.84' Storage=257 cf Inflow=0.29 cfs 851 cf Outflow=0.06 cfs 851 cf Pond INF1: PROP UG INFILTRATION SYSTEM-1 Peak Elev=142.95' Storage=724 cf Mow--0.60 cfs 1,850 cf Discarded=0.01 cfs 433 cf Primary=0.22 cfs 1,033 cf Outflow=0.22 cfs 1,465 cf Pond INF2: PROP UG INFILTRATION SYSTEM-2 Peak Elev=144.23' Storage=220 cf Inflow=0.15 cfs 426 cf Discarded=0.00 cfs 391 cf Primary=0.00 cfs 0 cf Outflow--0.00 cfs 391 cf Pond OW1: PROP OIL/WATER SEPARATOR#1 Peak Elev=142.96' Inflow--0.45 cfs 1,639 cf 8.0" Round Culvert n=0.013 L=11.0' S=0.0045'/' Outflow--0.45 cfs 1,639 cf Pond TDl: PROP TRENCH DRAIN 1 Peak Elev=140.75' Inflow--0.22 cfs 590 cf 6.0" Round Culvert n=0.013 L=2.0' S=0.0500'/' Outflow=0.22 cfs 590 cf Pond TD2: PROP TRENCH DRAIN 2 Peak Elev=140.62' Inflow--0.09 cfs 261 cf 6.0" Round Culvert n=0.013 L=3.0' S=0.0333'/' Outflow-0.09 cfs 261 cf Pond TD3• PROP TRENCH DRAIN 3 Peak Elev=145.58' Inflow--0.07 cfs 227 cf 6.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow=0.07 cfs 227 cf Pond TD4: PROP TRENCH DRAIN 4 Peak Elev=143.02' Inflow--0.27 cfs 834 cf 8.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow--0.27 cfs 834 cf Total Runoff Area=30,715 sf Runoff Volume=3,664 of Average Runoff Depth=1.43" 42.51%Pervious=13,056 sf 57.49%Impervious= 17,659 sf 305312-Postdrain--Rev4 Type 11124-hr 10 year Rainfall=4.50" Prepared by MHF Design Consultants,Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 5 Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method,UH=SCS Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1S: RUNOFF TO OSGOOD STREET Runoff Area=4,480 sf 29.31%Impervious Runoff Depth=2.55" Tc=5.0 min CN=81 Runoff=0.32 cfs 951 cf Subcatchment 2S: RUNOFF TO EASTERN Runoff Area=3,913 sf 0.00%Impervious RunoffDepth=1.90" Tc=5.0 min CN=73 Runoff---0.20 cfs 618 cf Subcatchment 3S: RUNOFF TO TRENCH DRAIN 1 Runoff Area=4,400 sf 72.11%Impervious Runoff Depth=3.50" Tc=2.0 min CN=91 Runoff=0.46 cfs 1,283 cf Subcatchment 11S: RUNOFF TO CB-1 Runoff Area=6,861 sf 57.32%Impervious Runoff Depth=3.20" Tc=5.0 min CN=88 Runoff-0.60 cfs 1,827 cf Subcatchment 12S: RUNOFF TO TRENCH Runoff Area=1,200 sf 100.00%Impervious Runoff Depth=4.26" Tc=5.0 min CN=98 Runoff=0.13 cfs 426 cf Subcatchment 13S: RUNOFF TO TRENCH DRAIN Runoff Area=5,095 sf 89.01%Impervious Runoff Depth=3.92" Tc=5.0 min CN=95 Runoff=0.52 cfs 1,666 cf Subcatchment 14S: RUNOFF TO TRENCH DRAIN Runoff Area=2,517 sf 49.90%Impervious Runoff Depth=3.00" Tc=5.0 min CN=86 Runoff--0.21 cfs 630 cf Subcatchment ROOF: ROOF RUNOFF Runoff Area=2,249 sf 100.00%Impervious Runoff Depth=4.26" Tc=0.0 min CN=98 Runoff=0.28 cfs 799 cf Reach DPl: DESIGN POINT#1 Inflow--0.57 cfs 2,864 cf Outflow--0.57 cfs 2,864 cf Reach DP2: DESIGN POINT#2 Inflow=1.01 cfs 3,663 cf Outflow=1.01 cfs 3,663 cf Pond 1: PROP CB-1 Peak Elev=143.72' Inflow--0.60 cfs 1,827 cf 12.0" Round Culvert n=0.013 L=58.0' S=0.0050'/' Outflow--0.60 cfs 1,827 cf Pond 3P• PROP UNDERGROUND SAND FILTER Peak Elev=138.37' Inflow--0.64 cfs 1,913 cf 12.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow--0.64 cfs 1,913 cf Pond Dl: PROP DMH-1 Peak Elev=143.65' Inflow=0.73 cfs 2,254 cf Primary=0.11 cfs 1,208 cf Secondary=0.73 cfs 1,045 cf Outflow--0.73 cfs 2,254 cf Pond DIA: PROP DMH-IA Peak Elev=143.67' Inflow-0.73 cfs 2,254 cf 12.0" Round Culvert n=0.013 L=12.0' S=0.0200'/' Outflow=0.73 cfs 2,254 cf Pond D2• PROP DMH-2 Peak Elev=143.77' Inflow--0.52 cfs 1,666 cf 8.0" Round Culvert n=0.013 L=38.0' S=0.0039'/' Outflow=0.52 cfs 1,666 cf Pond D2A• PROP DMH-2A Peak Elev=143.72' Inflow=0.52 cfs 2,875 cf 8.0" Round Culvert n=0.013 L=3.0' S=0.0067'/' Outflow--0.52 cfs 2,875 cf 305312-Postdrain--RM Type X24-hr 10 year Rainfall=4.50" Prepared by MHF Design Consultants,Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Page 6 Pond D4• PROP DMH-4 Peak Elev=138.27' Inflow=0.64 cfs 1,913 cf 12.0" Round Culvert n=0.013 L=34.0' S=0.0206'/' Outflow=0.64 cfs 1,913 cf Pond DET: PROP.UG DETENTION SYSTEM Peak Elev=138.24' Storage=473 cf Inflow=0.64 cfs 1,913 cf Outflow=0.28 cfs 1,913 cf Pond INFl: PROP UG INFILTRATION SYSTEM-1 Peak Elev=143.63' Storage=1,080 cf Inflow--l.24 cfs 3,920 cf Discarded=0.01 cfs 479 cf Primary=0.84 cfs 3,045 cf Outflow--0.85 cfs 3,524 cf Pond INF2: PROP UG INFILTRATION SYSTEM-2 Peak Elev=144.71' Storage=510 cf Inflow-0.28 cfs 799 cf Discarded=0.00 cfs 433 cf Primary=0.00 cfs 0 cf Outflow=0.00 cfs 433 cf Pond OWI: PROP OILIWATER SEPARATOR#1 Peak Elev=143.67' Inflow--0.52 cfs 2,875 cf 8.0" Round Culvert n=0.013 L=11.0' S=0.0045'/' Outflow--0.52 cfs 2,875 cf Pond TDI: PROP TRENCH DRAIN 1 Peak Elev=140.94' Inflow=0.46 cfs 1,283 cf 6.0" Round Culvert n=0.013 L=2.0' S=0.0500'/' Outflow--0.46 cfs 1,283 cf Pond TD2: PROP TRENCH DRAIN 2 Peak Elev=140.74' Inflow--0.21 cfs 630 cf 6.0" Round Culvert n=0.013 L=3.0' S=0.0333'/' Outflow--0.21 cfs 630 cf Pond TD3• PROP TRENCH DRAIN 3 Peak Elev=145.65' Inflow=0.13 cfs 426 cf 6.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow--0.13 cfs 426 cf Pond TD4• PROP TRENCH DRAIN 4 Peak Elev=143.83' Inflow=0.52 cfs 1,666 cf . 8.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow=0.52 cfs 1,666 cf Total Runoff Area=30,715 sf Runoff Volume=8,201 of Average Runoff Depth=3.20" 42.51%Pervious=13,056 sf 57.49%Impervious= 17,659 sf 305312-Postdrain--ReA Type 11124-hr 100 year Rainfall=6.40" Prepared by NMF Design Consultants,Inc Printed 3/28/2013 HydroCAM 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Pave 7 Time span=0.00-30.00 hrs,dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method,UH=SCS Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1S: RUNOFF TO OSGOOD STREET Runoff Area=4,480 sf 29.31%Impervious Runoff Depth=4.25" Tc=5.0 min CN=81 Runoff=0.53 cfs 1,587 cf Subcatchment 2S: RUNOFF TO EASTERN Runoff Area=3,913 sf 0.00%Impervious Runoff Depth=3.42" Tc=5.0 min CN=73 Runoff=0.37 cfs 1,116 cf Subcatchment 3S: RUNOFF TO TRENCH DRAIN 1 Runoff Area=4,400 sf 72.11%Impervious Runoff Depth=5.35" Tc=2.0 min CN=91 Runoff--0.69 cfs 1,961 cf Subcatchment 11S• RUNOFF TO CB-1 Runoff Area=6,861 sf 57.32%Impervious Runoff Depth=5.01" Tc=5.0 min CN=88 Runoff=0.92 cfs 2,866 cf Subcatchment 12S: RUNOFF TO TRENCH Runoff Area=1,200 sf 100.00%Impervious Runoff Depth=6.16" Tc=5.0 min CN=98 Runoff=0.18 cfs 616 cf Subcatchment 13S: RUNOFF TO TRENCH DRAIN Runoff Area=5,095 sf 89.01%Impervious Runoff Depth=5.81" Tc=5.0 min CN=95 Runoff=0.75 cfs 2,466 cf Subcatchment 14S: RUNOFF TO TRENCH DRAIN Runoff Area=2,517 sf 49.90%Impervious Runoff Depth=4.79" Tc=5.0 min CN=86 Runoff=0.33 cfs 1,005 cf Subcatchment ROOF: ROOF RUNOFF Runoff Area=2,249 sf 100.00%Impervious Runoff Depth=6.16" Tc=0.0 min CN=98 Runoff--0.40cfs 1,155 cf Reach DPl: DESIGN POINT#1 Inflow--0.92 cfs 4,824 cf Outflow--0.92 cfs 4,824 cf Reach DP2: DESIGN POINT#2 Inflow--2.12 cfs 6,162 cf Outflow--2.12 cfs 6,162 cf Pond l: PROP CB-1 Peak Elev=144.05' Inflow=0.92 cfs 2,866 cf 12.0" Round Culvert n=0.013 L=58.0' S=0.0050'/' Outflow-0.92 cfs 2,866 cf Pond 3P: PROP UNDERGROUND SAND FILTER Peak Elev=138.73' Inflow=0.97 cfs 2,966 cf 12.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow=0.97 cfs 2,966 cf Pond Dl• PROP DMH-1 Peak Elev=143.90' Inflow=1.10 cfs 3,482 cf Primary=0.10 cfs 1,615 cf Secondary=1.10 cfs 1,867 cf Outflow=1.10 cfs 3,482 cf Pond DIA: PROP DMH-1A Peak Elev=143.98' Inflow=1.10 cfs 3,482 cf 12.0" Round Culvert n=0.013 L=12.0' S=0.0200'/' Outflow=1.10 cfs 3,482 cf Pond D2: PROP DMH-2 Peak Elev=144.41' Inflow=0.75 cfs 2,466 cf 8.0" Round Culvert n=0.013 L=38.0' S=0.0039'/' Outflow=0.75 cfs 2,466 cf Pond D2A• PROP DM11I-2A Peak Elev=144.19' Inflow--0.75 cfs 4,082 cf 8.0" Round Culvert n=0.013 L=3.0' S=0.0067'/' Outflow=0.75 cfs 4,082 cf 305312-Postdrain--RM Type11124-hr 100 year Rainfall=6.40" Prepared by MHF Design Consultants,Inc Printed 3/28/2013 HydroCAD® 10.00 s/n 01710 ©2012 HydroCAD Software Solutions LLC Paye 8 Pond D4: PROP DMH-4 Peak Elev=138.71' Inflow=0.97 cfs 3,237 cf 12.0" Round Culvert n=0.013 L=34.0' S=0.0206'/' Outflow--0.97 cfs 3,237 cf Pond DET: PROP.UG DETENTION SYSTEM Peak Elev=138.70' Storage=708 cf Inflow-0.97 cfs 3,237 cf Outflow--0.43 cfs 3,237 cf Pond INFI: PROP UG INFILTRATION SYSTEM-1 Peak Elev=143.83' Storage=1,165 cf Inflow-1.85 cfs 5,948 cf Discarded=0.01 cfs 502 cf Primary=1.76 cfs 5,046 cf Outflow=1.76 cfs 5,548 cf Pond INF2: PROP UG INFILTRATION SYSTEM-2 Peak Elev=144.86' Storage=609 cf Inflow=0.40 cfs 1,155 cf Discarded=0.00 cfs 460 cf Primary=0.04 cfs 271 cf Outflow--0.04 cfs 731 cf Pond OWl: PROP OIL/WATER SEPARATOR#1 Peak Elev=144.01' inflow=0.75 cfs 4,082 cf 8.0" Round Culvert n=0.013 L=11.0' S=0.0045'/' Outflow=0.75 cfs 4,082 cf Pond TDl: PROP TRENCH DRAIN 1 Peak Elev=141.23' Inflow--0.69 cfs 1,961 cf 6.0" Round Culvert n=0.013 L=2.0' S=0.0500'/' Outflow--0.69 cfs 1,961 cf Pond TD2• PROP TRENCH DRAIN 2 Peak Elev=140.84' Inflow=0.33 cfs 1,005 cf 6.0" Round Culvert n=0.013 L=3.0' S=0.0333'/' Outflow-0.33 cfs 1,005 cf Pond TD3: PROP TRENCH DRAIN 3 Peak Elev=145.70' Inflow=0.18 cfs 616 cf 6.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow=0.18 cfs 616 cf Pond TD4: PROP TRENCH DRAIN 4 Peak Elev=144.58' Inflow--0.75 cfs 2,466 cf 8.0" Round Culvert n=0.013 L=5.0' S=0.0100'/' Outflow--0.75 cfs 2,466 cf Total Runoff Area=30,715 sf Runoff Volume=12,772 cf Average Runoff Depth=4.99" 42.51%Pervious=13,056 sf 57.49%Impervious=17,659 sf APPENDIX D POST DEVELOPMENT Increased Volume Computations In order to address the increased volume associated with development of the site, an analysis of the receiving downstream wetland area has been performed in order to address the potential impact of the increased volume of runoff associated with the development of this project. Although not specifically outlined in the drainage regulations outlined in the Town of North Andover By-Laws through the Watershed Special Permit application process or in the Town of North Andover Site Plan Regulations, it has been common practice under these two sections of the regulations to address the issue of additional volume generated as a result of development. The runoff from a portion of the site after being treated for volume and quality issues is conveyed from the on-site detention system into the Osgood Street drainage system. This flow is then conveyed easterly thru the existing Osgood Street drainage system to an outflow located approximately 800 linear feet to the east. See Drawing entitled"Overview of Existing Drainage System" located in this report. The outlet of this system is a headwall located easterly of the existing driveway for the restaurant located just to the east of the project site and drains to a large ponded wetland complex that conveys runoff in a northerly direction under Commerce Way/Holt Road and eventually to the Merrimack River. This ponded area is depicted on the USGS Quadrangle and is shown on the attached sketch labeled SK-1. The ponded area was calculated to have an area of approximately 80,000 sf An overview of this area is also depicted on SK-2 and SK-3. The larger wetland area associated with this outfall is calculated to have an area of 262,000 sf or 6 acres. To be conservative, however,the calculations for the rise in the elevation based on the increased volume for the project will be based on the ponded area shown, Based on the HydroCad analysis performed for the project,the increase in volume from the site to the existing drainage system in Osgood Street and the outfall area described above was calculated to be 1,523 cf The rise in the ponded wetland area as a result of the increased volume associated with the additional runoff from the project can be calculated as follows: 1,523 cf(additional volume)/ 80,000 sf(ponded area)= 0.019 ft or 0.22 inches. This increase in height is negligible with respect to the watershed of the area. Further, if the entire wetland area were assumed the increase would be calculated as follows: 1,523 cf(additional volume)/262,000 sf(ponded area)= 0.0058 ft or 0.07 inches. Based on these minimal increases calculated above,there will be no impact of flooding to these downstream receiving areas. ' r r t r � I r • r _ r APPROXIMATE LOCATION OF AREA OF EXISTING SURFACE WATER OUTFALL IN WETLAND 80,000 SF± r 06 INN Will � r 1 DRAWN BY: CCC U.S.G.S. QUADRANGLE - - _ -= ►_ = MHF JOB #:MHF JOB #: 305311�� JFJ HOLDING, LLC MHF Design Consultants,Inc. SCALE: 1"=200'f FIGURE 44 Stiles Road, Suite One 1018 OSGOOD STREET Salem, New Hampshire 03079 NORTH ANDOVER, MASSACHUSETTS (603) 89sign.c DATE: 3/26/13 SK-1 www.m ANNER n.com ENGINEERS•PLANNERS•SURVEYORS cl YT 'vo-T1 EXISTING PONDED AREA APPROXIMATE LOCATION OF rj; 'q;') I EXISTING EXISTING OUTFALL RESTAURANT G 1200 m el DRAWN BY: CCC MAP VIEW MHF JOB #: 305311 JFJ HOLDING, LLC MHF Design Consultants, Inc. FIGURE 44 Stiles Rood, Suite One SCALE: 1"=500'± 1018 OSGOOD STREET Salem, Now Hampshire 03079 (603) NORTH ANDOVER, MASSACHUSETTS www.m893-0720 hfdosign.com DATE: 3/26/13 SK-2 ENGINEERS- PLANNERS-SURVEYORS r�, APPROXIMATE AREA OF WETLAND COMPLEX 262,000 SF± 17, EXISTING RESTRAURANT ,.,, EXISTING OUTFALL 6k �. DRAWN BY: CCC AERIAL VIEW MHF JOB #: 305311 JFJ HOLDING, LLC MHF Design Consultants, Inc. SCALE: 1"=5oo'f FIGURE 44 Stiles Road, Su 1018 OSGOOD STREET ra One Salem, New Hampshire 03079 (603) 893-0720 3/26/13 NORTH ANDOVER, MASSACHUSETTS www.mhfdosign.com DATE: SK-3 ENGINEERS•PLANNERS•SURVEYORS