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HomeMy WebLinkAbout2019-06-04 Stormwater Report (Part 1) 05/07/19 f 1 ))tFiFi{ III 4 e 0-.-- W GHORC;Ii STRU,].," ',SUI'1'1?209,LOWELL, MA 01852 ® 978-201-9390 ® WWW.LANDPLIZX.COM CONSUINING SURVEYING CIVIL LNGINIi1 RNG ® GEO-T1:CI-INICAL STORMWATER REPORT 1725 TURNPIKri STREET NORTH ANDO'VER, MASSACHUSE'll'S FEBRUARY 22, 2019 REVISED: MAY 7, 2019 p -S•. il11 O wo.t PREPARED FOR: A.L. PRIMI; ENERGY CONSULTANTS, LLC 18 LARK AVI;NLJ}; SAUGUS, MA 0 1906 3 i f I I i TABLE OF CONTENTS: SECTION 1.0 PItOJEGT NARRATIVE WITH SUMMARY TABLE AND MASSIDEP STORMWATER STANDARDS 1.1 PROJECT NARRATIVE I 1.2 MASsDrP STORMWATER STANDARDS 1.3 STORMWA'rm3 CIIECKLIST SECTION 2.0 MAPS 2.1 Locus-GIS MAP 2.2 USGS ToPOGRAPI IIC MAP 2.3 FEMA FLOOD PLAIN MAP 2.4 WEII SOII S SURVEY SOILS MAP SECTION 3.0 STORMWATER CALCULATIONS AND DATA 3,1 DRAINAGE CALCULATIONS (HYDROCAD DATA) WITH PRE VS. POST SUBCATCHMENT PLANS SECTION 4.0 CONSTRUCTION-PI;ItIOD, OPERATION & MAIN'I'ENANCE,AND LONG- TERM POLLUTION PREVENTION PLAN 4.1 INTRODUCTION 4.2 RESPONSIBLE PAR'rII41S 4.3 CONSTRUCTION PERIOD MAIN'I'LNANCE PROCEDURES 4.4 Pos'r-D1?VELOPMI!NT PERIOD MAINTENANCI?PROCEDURES 4.5 LUI-IPPL PRACTICES 4.6 ILLICIT DISCHARGE STATEMI-NT 4.7 MOSQUITO CONTROL 4.8 OPERATION AND MAINTENANCI3 BUDGET 4.9 RrsPONSIBLE PARTY SIGNATURES 4.10 STORMWATER MANAGEMENT PLAN 4.11 INSI'IC1'ION LOG SECTION 5.0 ATTACI-EMENTS 5.1 STORMTECII SC-740 SPECIFICATIONS & DRAWINGS 5.2 STORMTLlCI'I CONSTRUCTION Guii)E 5.3 SOIL LOGS LANDPLLX,LLC m 10 GE"0RGE S'I'.,SUI'I'Ii 208,LOWELL,MA 01852 0 978-201-9390 a WWW.LANI)PI,F-X.COM 1 IE I 1 i e I SECTION e PROJECT NARRATIVE WITH IT SUMMARY TABLE AND MAssDEPSTO ATER STANDARDS LANDPLEX, LLC r 10 CI ORGE ST.,SUITE;208, LOWELL, MA 01852 ® 978-201-9390 e WWW,I-ANI)PLI;X.COM 1 i E i i SECTION 1.1 - Plto.p:_m, NARRATIVE The subject property, 1725 Turnpike Street, is located in the General Business "Zoning District in the town of North Andover, Massachusetts, The subject properly contains 0.54± acres of area and has 390.81 linear feet of frontage along the Southwesterly side of Turnpike Street. Currently, the property contains a gas station with fuel pumps and parking. The on-site soils, as identified by (lie USDA Natural Resource Conservation Service Web Soil Survey, consist of hydrologic Soil Group "C" type soils. Oil site soil testing identified the Soil as hydraulic soil group "A". The subject property gradually Slopes from the rear of(he property to (he front of the property along`rurnpike Street. No portion 01'the subject property is located within a Federal Emergency Management Agency (FEMA) classified Blood Ilazard Area as shown oil Department H.U.D. Federal Insurance Administration Maps, per neap n(Imber 25009CO239F effective July 3, 2012. The owner proposes to raze the existing gas station and proposed a new gas Station with fuel pumps and parking. StOrlIMIter runoff front the roof of the proposed gas station and gas punip canopies will be treated and mitigated through Subsurface infiltration systems (Stornitech SC-740 Chambers). LANDPLEX, I LC ® I MA f}1852 w 978-2f}1„939f} ® WWW,LANDPLFX.COM i i l 1 SLMON 1.2 - MAssDEP S TORMWATER STANDARDS ,STANDARD l -No new stontrwerter conveyances(e.g. oufladls)may discharge untreated slor•m►vater directly to or eatme erosion in wellcrnds or waters oj'the Conmron►vealth. Ail new impervious areas are infiltrated cm sita. I This Standard is met. STANDARD 2 - Storotuaatr rururagcnrent a;►'stints shall be designed so that post-development peak disrharge reties tlo not c.ecccr(prt rlevclnpsu'ni peak disrharge roles. The ronowing treble summarises tite Pre- vs. fast-devviopment runoff ealeulaliotis from the attached HydroCAD data,demonstrating compliance with Standard 2: i 1.R 211 Analysis Point Turnpike Catch Street Basin 2-YEAR Pre Runoff(cfs) 0.25 0.44 (3.1 in.) Post Runoff(cfs) 0.14 0.44 Change -0.11 -0.00 (-44.0i) (-0%) 10-YEAR Pre Runoff(cfs) 0.51 0.85 (4.5 in.) Past Runoff(cfs) 0.31 0.82 Change -0.20 -0.03 (-39.2%) (-3.5%) 100-YEAR Pre Runoff(cfs) 0.91 1.46 (6.4 1n.) [0.0618f] [0.099af] Post Runoff(cfs) 0.57 1.37 [0.039af] [0.094af] Change -0,34 -0.09 (-37.4%) (-6.2%) This Standard is rncl. STANDARD J - Loss of amwal recharge to groundwater shall be eliminated or minimized through the list. of M.11ltratlon measures including site design, low impact development techniques, stoninvaler best management praetices, and good operation and maintenance.At a minimum, the amoral recharge,jronr the pnst- development site Shall approximate the ctntrual recharge front pre-development Conditions based on soil lope. This Standard is reel when Nut sturnrtvrrler rrrcntagernerrt.+;t'stcur is designed to hlliltrate the required recharge volume rrs determined in acrordamw with the Massachusetts Stornavater Handbook. Re(Itih'ed Recharge Volume(Rv) IZv=Total Post-Dev. Impervious Area(st) *0.60 inches liar A-type soils `a` 1112 Winches IZv=4,837±sl*'0.60 incites 1112 !1/inches IZv=2424-Cf "The proposed subsurhace inliltrati(trr systems have a total volume of 2,201±d, which exceeds the Required Recharge VOI LMIC. LANDPLI X,LLC 10(I14012(:11, S'1'., SUITE 209, LOWELL,MA 01852 ®978-201-9390 WWW.LANDIUMCOM I i i 0 C,dqul.jl_tul DI'awdown Times: i Pond ZP,Substwface Infiltrators(S18I) Ihawdown`1'imc =Storage Volume/(K`I° Bottom Area) =(2,201±cf)/(8.27 in/hi- (I l'ooi/12 inches) ` 1,041±,Si) =3.1 Hours 3.1 flours[72 Hours. This Standard is nlel. STANDARD 4- Stormwater management.91SIeVi's shall be designed to remove 8()1A vl'the average annual post- construction load trl'T'otrd Suspended Solids(7S'.S). This Stcrrrdarrl is met when; (tr)Sidlable practicesftvsotoce control and polhttion preventlon are itlewt f ed in it fang-terrn pollution prevention pltin, and tkereq ter twe implemented and maintained;(b)Strmclaral slormlwater best management piwaices are sized to capture the required haler qualify volume determind in accordance with the Mtrssachuseus Stvrmweww Handbook;turd(c)Pretreatment is provided in accordance with the Altrssachusells Sformwaler-Handbook. The proposed r(lol'umlopy inflltratiotl will reduce the iknlO(1111 O1'run0l'i'llOWinlglhl'Ougll the site and reduce file milounl of Tss being discharged. This Standard is met to the maximum exIcilt practicable. STANDARDS - Land Use,,wick Higheir Potential Pvlinitall Loads(L.UILPPL). The proposed deva(opmellt is a LUJJPPL. Applicable Operational Practices; 1) Prcpare an emergency spill response and cleantip plan and have designated Imined person(s)available either on- site Or oil Call at all tines to promptly and properly implement flat plan and ill meliafely cleanup all spills, Keel) sullable Cleanup materials,such is dry adsorllant Inawrials,on-site to-allow prompt cleanup of -it spill. 2) Train employees Oil the proper use of I'nel dispensers. Post "No Topping OlT'signs(topping off gas hulks causes spillage:told vents gas fulllcs to the air). Make sure that flic automatic shutoff on the fuel nOizlc is fl.111C Oiling properly. 3) TIM Ilet'SOn COOdliCtillg the fuc] I1,411ISIe1' Illust Ile pl'escllt al the fllulnlg 13u1llp(111'Ing 1111101 li'allSlcr, parlicuha'ly at unatferlde(I or Sell-surv(:stations. 4) Keep drained (nil inters in a suitable.COI)Wille►'Or drE1111. Drums should Ile closed oil aul impervious pad with ticll(111tIto eontailllllelll. Applicable Design Practices: I) Design the fueling island to control shills, 2) The fueling pad should be paved with Portland content concrete,or equivalent. 3) The Iticling island should have It roof Or canopy to prevent the direct entry of precipitation unto the shill containlmml pad.'rite roof'or canopy should, of it minillium, cover tilt spill canlailliltcnl pad %vithin the grade break or Biel dispensing area and preferably extend several additional feel to reduce.the inlroducllon of windhlown rain. Convey all roof'drains to Sturm drains Outside the fueling Conlaimrlem MINI. 4) Transli:r file fuel from file delivery tank trucks to the fuel storage lank ill i11111C1'viallS Contained areas and ensure. that appropriate overflow proleclion is used. Alternatively,cover nearby storm drains during file filling process and use drip pans lnldcr all hose e11111CCO0nS. 'Ellis Standard is niet. LANDPLEIX, LLC ® 10 G1 ORGL' ST.,SIJ1'1'I;209, L.OWE'LL, MA 01852 m 978-201-9390 a WWW.LANDPLEX.COM ��` I STANDARD 6- Storinwafer discharges within crifical areas. 1 The proposed development is not located within a critical area. This Standard is not applicable. f STANDARD 7 d Redevelopment Projects. The proposed rc-devc1opillem 11"Is been designed to t'lllly Comply with the Storinwater%andaards to the extent I practicable, This Standard is Ina ,STANDARD 8-A plan to control rrnr,s7r rrctifJra relater!impacts including erosion, sedimentation, and other polhnant sources flaring construction and land disturbance activities(Construction period erosion, sedimentation, and pollarfion prevention plan)shall he developed and implemen feel, Please I-der to the Construction, Operation and Maintenance, and Long-torn Pollution Prevention Plan, 'rilis Slamiarrti is met. STANDARD 9-A long-term operation and nwhifenrnce plan shall he developed and implemented to ensure that slormlvater raurrafrgcrrrcrat systcm,s lirnction as designed. Please refer to the ConstrrrCflon, Operation and Maintenance, and Long-torn Pollution Prevention Plan, Tllis Standard is nlct. STANDARD 10 -All illicil dim—harge.s to the Worinwalet,rnanagemeilf,system are prohlbited. All Illicit discharges to the proposed storlllwater maalagenlOW system are prollibiled. Filrthormorc,all illicit discharges to thu Town al'North Andover storlmwater management system are prohibited, No illicit discharges exist on the site and the design o[ Elie s(ol'lilwater management systems do not allow the entry of any illicit discharges into it,consistent with Elie Slormwallcr Handbook Volume 1,Chapter 1,Standard 10. Please rct'er to the Construction, Operation and Maintenance, and Long-term Pollution Prevention Plait. This Standard is met, LANDPLEX, LLC" 10 C;I OR(jl3 ST.,SUI'I'I?208, LOWELL, MA 01852 978-201-9190 ® W)AW.LANDPLLX.C{)M Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for "1113"tormwater Report � E A. Introduction important:when A Stormwater Report must be submitted with the Notice of Intent permit application to document fining out terms compliance with the Storrrtwater Management Standards.The following checklist is NOT a substitute for Oil the computer' the Stormwater Re ors which should rovide more substantive and detailed information but is offered use only the tab p { p � ?, 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. , {,, :Yr ! t,.�. I The Stormwater Report must be prepared and Volume 3 of the ��E<s fi fc;i,E r E '� ,,� ; ,; r�-;. LJIcertified by a Registered Professional Engineer (RPE) licensed in the Commonwealth. The Stormwater Report must include: rf�, • 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 flan required by Standard 8' ® 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, MRCS 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. It not included in the Stormwater Report,Elie Illicit Discharge Compliance statement must be submitted prior to the discharge of stormvrater runoff to the post-construction best management practices. 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 ovont,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 disturbanGo activity on the site. swchock•p4l01/08 Stormwater Ariport Checklist•Page f of 8 Massachusetts Department of Environmental protection Bureau of Resource Protection - Wetlands Program Ll Checklist for Stormwater Rewrt B. Stormwater Checklist and Certification s 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. (Vote:Because stormwater requirements vary from project to project, it is possible that a complete Stormwater Report may not include information on some of the subjects specified in the Checklist. If it is determined that a specific item does not apply to the project under review, please note that the item is not applicable (N.A.) and provide the reasons for that determination. A complete checklist must include the Certification set forth below signed by the registered Professional Engineer who prepared the Stormwater Report. Registered professional Engineer's Certification have reviewed the Stormwater Report, including the soil evaluation, computations, Long-term Pollution Prevention Plan, the Construction Period Erosion and Sedimentation Control Plan (if included), the Long- term Post-Construction Operation and Maintenance Plan, the Illicit Discharge Compliance Statement (if included) and the plans showing the stormwater management system, and have determined that they have been prepared in accordance with the requirements of the Stormwater Management Standards as further elaborated by the Massachusetts Stormwater Handbook. I have also determined that the Information presented in the Stormwater Checklist is accurate and that the information presented in the Stormwater Report accurately reflects conditions at the site as of the date of this permit application, Registered Professional Engineer Block and Signature °t-- rlCt3rR7 ��� - �,iIS;Hr1Fl. CML VAS Ile fiSSrON.1l�'Ci� d Signature n D'alie _ Checklist Project Type: Is the application for new development, redevelopment, or a mix of new and redevelopment? ❑ New development ❑ Redevelopment © Mix of Now Development and Redevelopment swchock•04/01/08 $tormwaler Reporl checklist•Page 2 of 8 9 Massachusetts Department of Environmental Protection � Bureau of Resource Protection _ Wetlands Program Checklist for 0*'A 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) ❑X Minimizing disturbance to existing trees and shrubs ❑ LID Site Design Credit Requested: ❑ Credit i ❑ Credit 2 ❑ Credit 3 ❑ Use of'country drainage" versus curb and gutter conveyance and pipe ❑ Bioretention Cells (includes Rain Gardens) ❑ Constructed Stormwater Wetlands (includes Gravel Wetlands designs) ❑ Treebox Filter ❑ Water Quality Swale ❑ Grass Channel ❑ Green Roof ❑ Other(describe); Standard 1: No New Untreated Discharges ❑X 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. svwcheck•04/01/08 Stormwater Deport ChookEist•I'a6e 3—of I Massachusetts Department of Environmental protection Bureau of Resource Protection - Wetlands Program Checklist forr 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, X❑ 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. 0 static ❑ Simple Dynamic ❑ Dynamic rield' ❑ Runoff from all impervious areas at the site discharging to the infiltration BMP, ❑ Runoff from all impervious areas at the site is notdischarging 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, 0 Recharge BMPs have boen 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. 21 E 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, EX) Calculations showing that the infiltration BMPs will drain in 72 hours are provided, 0 Property includes a M.G.L. c, 21 E site or- a solid waste landfill and a mounding analysis is included. '800%T35 removal Is required prior to discharge to Infiltration BIAP If Dynamic Field method is used. Sweheck•04/01/08 - Stomwater Report Checklist •Page 4 of 8 i -- - - Massachusetts Department of Environmental Protection � l` Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) �- Standard 3: Recharge (continued) ❑ 'rhe infiltration BMP is used to attenuate peak flows during storms greater than or equal to the 10- 1 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 i 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 I3MPs 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 lI 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, swchack-04/01/08 Stormwater Repoil Chocklisl•f 1zgo 5 of 8 --— — Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program C"hecklist for Stormwater Rwort Checklist (continued) Standard 4: Water Quality (continued) { The BMP Is sized (and calculations provided) based on: ❑ The 1/2"or 1"Water Quality Volume or ❑ The equivalent flow rate associated with the Water Quality Volume and documentation is provided showing that the BMP treats the required water quality volume. El The applicant proposes to use proprietary BMPs, and documentation supporting use of proprietary E 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 Stonnwater Handbook and submitting copies of the TAMP 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, ❑ Tile NPDES Multi-Sector General Permit does not cover the land use. [X LUl-IPPLs are located at the site and industry specific source control and pollution prevention measures have been proposed to reduce or eliminate the exposure of LUVIPPLs to rain, snow, snow melt and runoff, and been included in the long term Pollution Prevention Plan. ❑ All exposure has been eliminated. ❑ All exposure has not been eliminated and all BMPs selected are on MassDEP LUHPPL list. ❑ The LUHPPL has the potential to generate runoff with moderate to higher concentrations of oil and grease (e.g. all parking lots with >1000 vehicle trips per day) and the treatment train includes an oil grit separator, a filtering bioretention area, a sand filter or equivalent. Standard 6: Critical Areas ❑ The discharge is near or to a critical area and the treatment train includes only BMPs that MassDEP has approved for stormwater discharges to or near that particular class of critical area. ❑ Critical areas and BMPs are identified in the Stormwater Report. swcheck•04/01/08 Stormwaler Deport checklist•Pago 6 of f3 1 i Massachusetts Department of Environmental Protection \\� ' Bureau of Resource Protection - Wetlands Program Checklistfor Stormwater Report bhecklist (continued)--- Standard 7: Redevelopments and Other Projects Subject to the Standards only to the maximum extent practicable 0 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 multifamily 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 toot Path ❑ Redevelopment Project 0 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; O Detail drawings and specifications for erosion control BMPs, including sizing calculations; '', 6 Vegetation Planning; '',. * Site Development Plan; O Construction Sequencing Plan; ® Sequencing of Erosion and Sedimentation Controls; O Operation and Maintenance of Erasion and Sedimentation Controls; ', ® Inspection Schedule; ® Maintenance Schedule; m 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. swchock•04/01/08 Stormwater Report Checklist•Page 7 of a I E f 6 I Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report f Checklist (continued) Standard 0: Construction Period Pollution Prevention and Erosion and Sedimentation Control (continued) i ❑ The project is highly complex and information is included in the Stormwater Deport 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. E (C 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 boon 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: ® Narne of the stormwater management system owners; ❑X Party responsible for operation and maintenance; Schedule for Implementation of routine and non-routine maintenance tasks; 0 Plan showing the location of all stormwater BMPs maintenance access areas; ❑ Description and delineation of public safety features; ICJ 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. swcheck•04101/08 Stormwater Report Checklist•Page 8 of 8 i i i Sr4,C,T ON MAPS I ANDPLEX, LI,(.; IO G1,0RGE ST.,StJrri- 209, LOWHU., MA 01852 ®978-201-9390 ® W"I.LANT)PLLX.COM i I i i 3 9 FIGURE 2,1 Locus-GIS MAr (NOT BYO SCALE) - 1f17,lI iiii!13OIi0f111 � 101JI 0091,01100.0 107 1s{;0��),oUiiU,l) j� 11)!E�fr174R(;110!Y 1t�!I,�OS!�:nkl{)t�.1r lP1 IIIN)]9 40t)(s,tf' 10) 11,lif 1 tdtll) 1 9UCIfHl.O - LIP f s,14)1 14411J1.€ f)0 u. '. i 101,0 01a1)00W)0 2 11)1 11 4)1;tl iiq[?;1.0- 0000 i) LANDPLEX, LLC ® 10(iI:ORGI ST.,SUITH 208, LOWI LL, MA 01852 978-201-9390 w WWW.I.ANI)PI..I X.COM a F e E jE i FIGURE 2.2 USGS TOPOGRAPHIC MAI' (NOT TO SCALD!) 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Mal) Unit Legend Mall U1111 Symbol fliall U1111 Name Acres lit AOI Pelcom of A01 71 W 01 10001110 TOWI,for AmCl of 11110v,![ 0.7 LANDPLF.X, LLC 10 GEOROE s'r, SUITH 209, LOWELL,MA W HS2 e 978-201-9390 WWW.LAND1JLHX,COM 3 1 j I i i SECTION s STORMWArFER CALCULATIONS AND DATA L ANDPl,BX, IaLC` o IO GPORCl3 S'I'„ Sl1['I'F 208, LOWlg,l,,MA 01852 ! 978-201-9390 6 WWW,I,ANI)PLI?X.(,'OM �I Ols- Subcatchment 1 Turnpike Street 0 2S Subcatchment 2 Catch Basin Subcat Roach on Llnk Drainage Diagram for Turnplko-PRE-REVI Prepared by LandPlox, LLC 11mroCADO 7,10 sin 003067 02005 HydroCAD Software Solutions LLC l I I i Turnpike - PREWREV1 Type 11124-hr 2-Year Rainf611=3.10" Prepared by LandPlex, L.LC Page 2 H droCADO 7.10 sin 003867 ©2005 I-1 droCAD Software Solutions LLC r Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points { Runoff by SCS TR 20 method, UH=SCS Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1 S: Subcatchment 1 Runoff Area=9,490 sf Runoff Depth>0.94" Flow Length=108' Tc=6.0 min CN=75 Runoff=0.25 cfs 0.017 of ' 1 Subcatchment 2S: Subcatchment 2 Runoff Area=14,071 sf Runoff Depth>1.10" Flow Length=123' Tc=6.0 min CN=78 Runoff=0.44 cfs 0.030 of Reach 1 R: Turnpike Street Inflow=0.25 cfs 0.017 of Outflow=0.25 cfs 0.017 of Reach 2R: Catch Basin Inflow=.0.44 cis 0.030 of Outflow=0.44 cfs 0,030 of Total Runoff Area = 0.541 ac Runoff Volume = 0.047 of Average Runoff Depth 1.04" I i Turnpike - PRE-REV1 Type 11124-hr 2-Year Rainfall=3,10" Prepared by LandPlex, LLC Page 3 fly droCAD©7.10 sln 003867 0 2005 I-I droCAD Software Solutions L.L.0 i Subcatchment 1 S: Subcatchment 1 I Runoff 0.25 cfs a 12.10 hrs, Volume= 0.017 af, Depths 0.94" Runoff by SOS TR-20 method, Ul-I=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.10" Area (sl)_ ON Description 5,790 98 Paved parking & roofs 3,700 39_- _>75% Grass cover, Good, HSG A 9,490 75 Weighted Average -�_ i To Length Slope Velocity Capacity Description min feet ft/ft ft/sec cfs 0.7 50 0.0200 1.2 Sheet Flow, Sheet Flow Smooth surfaces n= 0.011 P2= 3.10" 0.3 58 0,0200 2.9 Shallow Concentrated Flow, Shallow Paved Kv= 20.3 fps 1.0 108 Total, Increased to minimum To = 6.0 min Subcatchment 2S: Subcatchment 2 Runoff = 0.44 cfs c@ 12.10 hrs, Volume= 0.030 af, Depth> 1.10" Runoff by SOS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3,10" Area sf ON Description 4,808 39 >75% Grass cover, Good, HSG A 9,263 98 Paved parkinp & roofs 14,071 78 Weighted Average To Length Slope Velocity Capacity Description min feet fVft ft/sec cfs 5.1 50 0.0260 0.2 Sheet Flow, Grass: Short n= 0.150 P2= 3.10" 0.1 10 0.0300 1.2 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 0.7 63 0.0060 1.6 Shallow Concentrated Flow, Paved Kv= 20.3 fps 5.9 123 Total, Increased to minimum To = 6.0 min Reach 1 R: Turnpike Street [401 Hint: Not Described (Outflow=inflow) Inflow Area = 0.218 ac, Inflow Depth > 0.94" for 2-Year event Inflow 0.25 cfs q) 12.10 hrs, Volume= 0.017 of Outflow 0.25 cfs @ 12.10 hrs, Volume= 0.017 af, Atten= 0%, Lag= 0.0 min 1 1 Turnpike m PRE-RRV1 Type 11!24-hr 2-Year Rainta11P3.10" Prepared by LandPlex, LLC Page 4 HdroCADO 7.1.0 8ln_003867 ©2005 HydroCAD Software Solutions LLC 3 Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs j 1 Reach 2R: Catch Basin 1401 Hint: Not Described (Outflow=lnflow) Inflow Area = 0.323 ac, Inflow Depth > 1.10" for 2-Year event Inflow 0.44 cis @ 12.10 hrs, Volume= 0.030 of Outflow - 0.44 efs @ 12.10 hrs, Volume= 0.030 af, Atten= 0%, Lag= 0.0 min i Routing by Dyn-Star-Ind method, Time Span= 5,00-20.00 hrs, dt= 0.05 his i i i i Turnpike r PRE-REV1 Type 11124-hr 10-Year Rainfall=4.50" Prepared by LandPkex, LLC Page 5 H droCADO 7.10 sln 003867 O 2005 H droCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Dyn-Star-Ind method - Pond routing by Dyn-Stor-Ind method 5ubcatchment 1S: Subcatchment 1 Runoff Area=9,490 sf Runoff Depth>1.90" Flow Length=108' Tc-6.0 rnin CN=75 Runoff=0.51 cfs 0.034 of 5ubcatchment 2S: Subcatchment 2 Runoff Area=14,071 sf Runoff Depth>2.113" Flow Length=123' "f c=6.0 rnin CN=78 Runoff=0.85 cfs 0.057 of Reach 1 R: Turnpike Street Inflow=0.51 cfs 0.034 of Outflow=0.51 cfs 0.034 of Reach 2R: Catch Basin Inflow=0.85 cfs 0,057 of Outflow=0.85 cfs 0.057 of Total Runoff Area 0.541 ac Runoff Volume 0.092 of Average Runoff Depth 2.04" I i 9 Turnpike - PRE-REV1 Type 11124-hr 10-Year Rainfall=4.50" Prepared by LandPlex, LLC Page 6 HydroCADO 7.10 sln 003867 4 2005 HydroCAD Software Solullons LLC Subcatchment 1 S: Subcatchment 1 Runoff = 0.51 cfs a 12.10 hrs, Volume= 0.034 af, Depth> 1.90" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5,00-20,00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall:4,50" 0 Area sf CN Description 5,790 98 Paved parking & roofs 3,700 39 >75% Grass cover, Good, HSG A 9,490 75 Weighted Average Tc Length Slope Velocity Capacity Description min feet ft/ft fusee cfs 0.7 50 0.0200 1.2 Sheet Plow, Sheet Flow Smooth surfaces n= 0.011 P2= 3.10" 0.3 58 0.0200 2.9 Shallow Concentrated Flow, Shallow Paved Kv= 20.3 fps 1.0 108 Total, Increased to minimum Tc = 6.0 min Subcatchment 2S: Subcatchment 2 Runoff - 0.85 cfs @ 12.09 hrs, Volume= 0.057 af, Depth> 2.13" Runoff by SCS TR-20 method, UH=SCS; Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4,50" Area sf CN Description 4,808 39 >75% Grass cover, Good, HSG A 9,263 98 Paved parkinq & roofs 14,071 78 Weighted Average Tc Length Slope Velocity Capacity Description min feet ft/ft ft/sec cfs 5.1 50 0.0260 0.2 Sheet Flow, Grass: Short n= 0.150 P2= 3.10" 0.1 10 0.0300 1.2 Shallow Concentrated Flow, Short Grass Pasture Kv- 7.0 fps 0.7 63 0.0060 1.6 Shallow Concentrated Flow, Paved Kv- 20.3 fps 5.9 123 Total, Increased to minimum Tc = 6.0 min Reach 1 R: Turnpike Street [401 Hint: Not Described (Oulflowrinflow) Inflow Area 0.218 ac, Inflow Depth > 1.90" for 10-Year event Inflow - 0.51 cfs @ 12.10 hrs, Volume= 0.034 of Outflow - 0.51 cfs @ 12.10 hrs, Volume= 0.034 af, Atten= 0%, Lag= 0.0 min 4 i i Turnpike - PRE-REV1 Type /I/24-tar 10-Year Ralnfall 4.50" Prepared by LandPlex, LLC Page 7 H droCADO 7.10 sln 003867 @; 2005 Fl droCAD Software Solutions LLC Routing by Dyn-Stor-Ind method, Time Shan= 5.00-20.00 hrs, dt= 0.05 hrs Reach 2R. Catch Basin 140) Hint: Not Described (Outflow=Inflow) Inflow Area = 0.323 ac, Inflow Depth > 2.13" for 10-Year event Inflow - 0.85 cis @ 12.09 hrs, Volume= 0.057 of Outflow = 0.85 cfs @ 12.09 hrs, Volume= 0.057 at, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs E I E Turnpike e PRE-REVI Type H/24-hr 100-Year Ralnfall=6.40" Prepared by LandPiex, LLC Page 8 H droCADO 7.10 s/n 003867 OO 2005 Hydro ',AD Software Solutions LI_C Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UW=SCS Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method i Subcatchment 1S: Subcatchment 1 Runoff Area=9,490 sf Runoff Depth>3.38" Flaw Length=108' Tc=6.0 min CN=75 Runoff=0.91 cfs 0.061 of Subcatchment 2S: Subcatchment 2 Runoff Area=14,071 sf Runoff Depth>MW Flow Length=123' Tc=6.0 min CN=78 Runoff=1,46 cfs 0.099 of Reach 1 R: Turnpike Street inflow=0.91 cfs 0.061 of Outflow=0.91 cfs 0.061 of Reach 2R: Catch Basin Inflow=1.46 cfs 0.099 of Outflow=1,46 cfs 0.099 of Total Runoff Area : 0.541 ac Runoff Volume : 0.161 of Average Runoff depth -3.56" E I E i I d Turnpike r PRE-REV11 Type U124-hr f 00-Year rainfall=6.40" Prepared by LandPlex, LLC Page 9 t i droCAD9 7.10 s/n 003867 ©2005 I-I droCAD Software Solutions t-LC j Subcatchment 1S: Subcatchment 1 e Runoff = 0.91 cfs @ 12.09 hrs, Volume= 0.061 af, Depth> 3.38" i Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs I Type III 24-hr 100-Year Rainfall=6.40" i Area sf CN Description 5,790 98 Paved parking & roofs - 3,700 39 >75% Grass cover, Good, HSG A 9,490 75 Weighted Average Tc Length Slope Velocity Capacity Description min feet ft/ft ft/sec cfs 0.7 50 0.0200 1.2 Sheet Plow, Sheet Flow Smooth surfaces n= 0.011 P2= 3.10" 0.3 58 0.0200 2.9 Shallow Concentrated Plow, Shallow Paved Kv= 20.3 fps 1.0 108 Total, Increased to minimum Tc = 6.0 min Subcatchment 2S: Subcatchment 2 Runoff - 1.46 cfs Qa 12.09 hrs, Volume= 0.099 af, Depth> 3.68" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type Ill 24-hr 100-Year Rainfall=6.40" Area sf CN Description 4,808 39 >75%Grass cover, Good, HSG A 9,263 98 Paved parking & roofs 14,071 78 Weighted Average Tc Length Slope Velocity Capacity Description min feet ft/ft) (fUsec) (cfs 5.1 50 0.0260 0.2 Sheet Flow, Grass: Short n= 0.150 P2= 3.10" 0.1 10 0.0300 1.2 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 0.7 63 0.0060 1.6 Shallow Concentrated Flow, Paved Kv= 20.3 fps 5.9 123 Total, Increased to minimum Te 6.0 min Reach 1 R. Turnpike Street (40] Hint: Not Described (Outflow=ln#low) I Inflow Area = 0.218 ac, Inflow Depth > 3.38" for 100-Year event Inflow 0.91 cfs cr 12.09 hrs, Volume= 0.061 of Outflow 0.91 cfs a 12.09 hrs, Volume= 0.061 af, Men= 0%, Lag= 0.0 min i i Turnpike - PRE-RIEV1 Type 11124-hr 100-Year Rainfallw6.40" Prepared by LandPlex, LL.0 Page 10 I I droCAD®7,10 sin 003667 O 2006 H droCAD Software Solutions LI_C Routing by Dyn-Stor-Ind method, Time Span 5,00-20.00 hrs, dt= 0.05 hrs Reach 2RI. Catch Basin 1401 Hint; Not Described (Outflow=lnflow) i Inflow Area = 0.323 ac, Inflow Depth . 3.68" for 100-Year event Inflow 1.46 cfs c@r 12.09 hrs, Volume= 0.099 of Outflow - 1.46 cfs @ 12.09 hrs, Volume= 0.099 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span 5.00-20.00 hrs, dt= 0.05 hrs