Attachment 7_SWPPP.pdf

Stormwater Pollution Prevention Plan Prepared in accordance with NYS DEC General Permit GP-0-15-002 for:

Western New York National Cemetery

Owner/Operator(s):

U.S. Department of Veterans Affairs 425 Eye Street, NW, 003C1A

Washington DC 20001 Phone # (202)632-5879

SWPPP Contact(s):

The LA Group, PC 40 Long Alley

Saratoga Springs, NY 12866 1-518-587-8100 1-518-587-0180

SWPPP Preparation Date:

February 28, 2018

Table of Contents

1.0 PERMIT OVERVIEW AND REQUIREMENTS

2.0 SWPPP REVIEW, UPDATE

2.1 SWPPP REVIEW

2.2 SWPPP UPDATE

3.0 PROJECT LOCATION AND DESCRIPTION AND SITE EVALUATION AND

PLANNING

3.1 PROJECT LOCATION

3.2 PROJECT DESCRIPTION

3.3 AREAS OF DISTURBANCE

4.0 SITE EVALUATION AND ANALYSIS

4.1 EXISTING SITE DEVELOPMENT

4.2 COVER TYPES

4.3 TOPOGRAPHY

4.4 SOILS

4.5 WETLANDS, SURFACE WATERS AND HYDROLOGY

4.6 CULTURAL RESOURCES DETERMINATION

4.7 RESOURCE MAPPING

4.8 EXISTING STORMWATER RUNOFF CONDITIONS

5.0 EROSION AND SEDIMENT CONTROL

5.1 EROSION AND SEDIMENT CONTROL PRACTICES

5.2 EROSION AND SEDIMENT CONTROL DRAWINGS

5.3 CONSTRUCTION PHASING PLAN AND SEQUENCE OF OPERATIONS

5.4 EROSION AND SEDIMENT CONTROL PRACTICE MAINTENANCE

5.5 EROSION AND SEDIMENT CONTROL INSPECTIONS

5.6 CONTRACTOR SEQUENCE FORM

6.0 POST CONSTRUCTION STORMWATER MANAGEMENT PLANNING

6.1 STORMWATER MODEL AND ANALYSIS

6.2 STORM EVENTS ANALYZED

6.3 PROPOSED STORMWATER RUNOFF CONDITIONS

6.4 WATER QUALITY VOLUME CALCULATIONS

6.5 GREEN INFRASTRUCTURE PRACTICES/RUNOFF REDUCTION CALCULATIONS

6.6 MINIMUM RRV BASED UPON HYDROLOGIC SOIL GROUP

6.7 WATER QUALITY VOLUME TREATMENT WITH STANDARD PRACTICES

6.8 HYDRAULIC AND HYDROLOGIC ANALYSIS

6.9 CHANNEL PROTECTION VOLUME (CPV)

6.10 COMPARISON OF PRE AND POST CONSTRUCTION STORMWATER RUNOFF

6.11 POST CONSTRUCTION STORMWATER MANAGEMENT DRAWINGS

7.0 POST CONSTRUCTION STORMWATER MAINTENANCE

7.1 MAINTENANCE TO BE PERFORMED

8.0 CONSTRUCTION WASTE

9.0 OFFSITE VEHICLE TRACKING

10.0 TEMPORARY STABILIZATION FOR FROZEN CONDITIONS

11.0 SOIL RESTORATION

11.1 SOIL RESTORATION REQUIREMENTS

12.0 SPILL PREVENTION PRACTICES

12.1 GOOD HOUSEKEEPING AND MATERIAL MANAGEMENT PRACTICES

12.2 INVENTORY FOR POLLUTION PREVENTION PLAN

12.3 HAZARDOUS PRODUCTS

12.4 SPILL PREVENTION

12.5 SPILL CONTROL PRACTICES

12.0 CERTIFICATIONS

13.0 DEFINITIONS

Appendices

A Notice of Intent (NOI), NYSDEC NOI Acknowledgement Letter

B HydroCAD Modeling Data & Stormwater Calculations

C Map Set – Location Map, Natural Resource Map, Master Plan, Grading Plan, and Erosion and Sediment Control Plan Map

D Soil Mapping and Geotechnical Results

E SWPPP Inspection Forms –SWPPP Inspection Report

F Other SWPPP Forms – Construction Sequence, SWPPP Plan Changes, Spill Response Form, Stormwater Management Practice Maintenance Log

G SPDES General Permit GP-0-15-002

H Historic Preservation Documentation

I Deep Ripping and De-compaction (DEC, 2008)

Stormwater Pollution Prevention Plan Western New York Cemetery 201512

1.0 PERMIT OVERVIEW AND REQUIREMENTS

This Stormwater Pollution Prevention Plan (SWPPP) has been prepared to inform the landowner and construction personnel of the measures to be implemented for controlling runoff and pollutants from the site during and after construction activities.

The objective of this plan is to comply with the New York Department of Environmental Conservation (NYSDEC) State Pollutant Discharge Elimination System (SPDES) General Permit for Stormwater Discharges from Construction Activities, Permit No. GP-0-15-002 requirements. Any material conflicts between this plan and the site plans, specification or instructions, must be brought to the attention of the design professional listed on the cover of this SWPPP. The project may have other permits, and it is the responsibility of the owner/operator and the contractor to know and understand all permits.

The operator will be issued a bill from New York State for a one hundred and ten dollar ($110.00) annual fee for the open GP-0-15-002 permit. The operator will also be billed by New York State for a one time one hundred and ten dollar ($110.00) per acre fee for the proposed disturbed soil area listed in the NOI, and finally a one-time six hundred and seventy five ($675.00) per acre fee for the proposed increased impervious area listed in the NOI.

The owner/operator is responsible to maintain onsite in a secure location that is accessible during normal working hours to an individual performing a compliance inspection, the following information:

the Notice of Intent (NOI), the NYS Department of Environmental Conservation NOI Acknowledgement

Letter, the SWPPP, a copy of the General Permit (included in the SWPPP), and All inspection reports, including necessary photographs.

Technical standards are detailed in the “New York State Standards and Specifications for Sediment and Erosion and Sediment Control (November 2016)”, as well as illustrated on the Erosion and Sediment Control Plan Map included in Appendix C. The design of post-construction stormwater control practices follow the guidance provided by “New York State Stormwater Management Design Manual” (January, 2015) (aka the Design Manual)

2.0 SWPPP REVIEW, UPDATE

2.1 SWPPP Review

Applicable Federal, State, and local regulatory agencies that have jurisdiction may elect to review this SWPPP and notify the owner/operator in writing that the SWPPP does not meet the requirements of their regulations. If the SWPPP needs to be revised, the owner/operator and the site contractor will make the required modifications within seven days of such notification and submit written certification to the notifying agency that the changes have been implemented. A copy of the current, updated SWPPP will be kept available on site for review by regulatory agencies, engineers, and subcontractors.

This Project is not located in a Regulated, Traditional Land Use Control MS4 Community.

2.2 SWPPP Update

The owner/operator shall amend the SWPPP under the following conditions:

Whenever the current provisions prove to be ineffective in minimizing pollutants in stormwater discharge from the site Whenever there is a change in design, construction or operation that could have an effect on the discharge of pollutants To address issues or deficiencies identified during an inspection by the qualified inspector, NYSDEC or other regulatory authority To identify a new subcontractor that will implement any part of the SWPPP.

The SWPPP PLAN CHANGES, AUTHORIZATION, AND CHANGE CERTIFICATION form (Appendix F) must be completed and a copy retained onsite during construction.

3.0 PROJECT LOCATION AND DESCRIPTION AND SITE

EVALUATION AND PLANNING

3.1 Project Location

The project is located in the Town of Pembroke, Genesee County in the western portion of New York State. The site is approximately 196 acres and is situated southeast of the Indian Falls Road and Alleghany Road intersection. The site abuts agricultural land to the north, east and west.

See Appendix C for a general site location map.

3.2 Project Description

The proposed project is for the construction of the New National Cemetery for Western New York. Full buildout of the cemetery will be conducted over approximately seven (7) phases. A Master Plan has been prepared for the project site, see Appendix C. The SWPPP and associated Stormwater calculations have been prepared for full buildout of the project. The project consists of constructing the following:

28,488 crypt burial plots 10,500 in-ground cremain plots

(4) four columbarium complexes Green burial site Maintenance building, (2) committal shelters, honor guard building, and an administrative building Over (2) miles of internal road network Site irrigation Wastewater disposal systems Stormwater management devices

Detailed Construction Drawings have been prepared for Phase 1. Future phases limits of disturbance and impervious areas have been assumed based on the Master Plan. Any deviations from the Master Plan will require a modification to the

SWPPP.

3.3 Areas of Disturbance

Phase 1 of the project will disturb approximately 53 acres of land and be completed in three (3) sub-phases. Each sub-phase will disturb more than five (5) acres at one time.

Areas of disturbance for future phases (Phases 2-7) are unknown at this time as detailed Construction Drawings have not been prepared yet. The SWPPP should be modified describing areas of disturbance once Construction Drawings have been prepared for the phase.

4.0 SITE EVALUATION AND ANALYSIS

4.1 Existing Site Development

The existing site consists of a mixture of uses. The northern portion of the property includes two (2) demolished residential homes. The central portion of the site consists of farmed land, approximately 30 acres. The remaining portion of the site consists of woods, wetlands, and pasture.

4.2 Cover Types

The existing surface cover for the site is primarily pasture/grass and woods while the proposed conditions include a portion of impervious pavement. The curve numbers utilized in the modeling were assigned based on cover type and HSG soil classification.

4.3 Topography

The site topography generally slopes from the north to the south. The majority of the topography along the southern portion of the site is flat, with elevations varying less than one foot over +/-50 acres. A small knoll is present along the northwestern portion of the site with slopes averaging 8% in the area. There are no significant steep slopes on-site.

4.4 Soils

A Geotechnical Report was completed by Fisher Associates dated June 1, 2016 for the Phase 1 of the project. The geotechnical report included analyzing the past geotechnical investigations and completing test borings and test pits. For reference the site was divided into four zones, see Appendix D for map. Zone A consists of approximately 14 feet of sand, silt, and clay with occasional cobbles. Zone B consists of approximately 3.5 to 7.5 feet of overburden overlying weathered limestone bedrock. The overburden generally consists of sand, gravel, clay, cobbles and boulders. Zone C predominantly consists of clay with bedrock increasing in depth from 9.5 feet deep along the north to 20 feet deep to the south in this area. Zone D was not investigated as it is designated as a wetland and is not suitable for development.

According to the Natural Resources Conservation Service (NRCS) Web Soil Survey, the majority of the project area is comprised of the following soils, with their corresponding hydrologic soil group classification: Ca-Canandaigua silt loam (HSG C/D), Lm-Lima silt loam (HSG C/D), Ng-Niagara silt loam (HSG C/D), On-Ontario loam (HSG C), and Ps-Phelps gravelly loam (HSG B/D).

See Appendix D for soils mapping and geotechnical mapping.

4.5 Wetlands, Surface Waters and Hydrology

State and US Army Corps wetlands are located on the project site. A large wetland complex is located along the central portion of the site and is approximately 50 acres in size. The wetland discharges to the Alleghany Road ditch, which flows south to twin 18-inch diameter culverts. The culverts cross under Alleghany Road and discharge to an unnamed channel, which according to NYSDEC Environmental Mapper is classified as a Class C stream.

Surface runoff from the northeastern portion of the site discharges to an existing manmade channel that flows north along the eastern site property line. The channel flows through a culvert under Indian Falls Road into an unnamed stream. The unnamed stream ultimately discharges to Tonawanda Creek, which is a Class B stream.

4.6 Cultural Resources Determination

The New York State Historic Preservation Office (SHPO) has determined the proposed project will have no adverse effect on historic properties. See Appendix H.

4.7 Resource Mapping

A Natural Resource Map has been developed which indicates natural resource areas and critical environmental areas to be protected, where feasible.

Jurisdictional Wetlands o Wetlands exist throughout the site and the development has been located to protect these wetlands to the greatest extent feasible. The project will impact approximately 0.74 acres of wetlands.

Waterways o No waterways are impacted by the Project as post-development flow rates will either be less than or equal to pre-development flow rates.

Floodplains o The Project is not within any floodplains.

Forest, vegetative cover o The site contains some woods in the wetland area. The forested area will generally be protected with limited clearing proposed as part of the project.

Topography/Steep slopes o The site is relatively flat with no steep slopes.

Existing soils, including hydrologic soil groups and soil erodibility o See Section 4.4 of this Report.

Drainage Patterns o See Section 4.8 of this Report.

Bedrock/Significant geological features o See Section 4.4 of this Report.

4.8 Existing Stormwater Runoff Conditions

Under the watershed’s Existing Condition, stormwater runoff from the site discharges to four off-site locations, see Attachment A for locations. The majority of the site drains to the southwest and is captured within the large on-site wooded wetland. The wetland temporarily detains runoff prior to discharging to the roadside ditch along Alleghany Road, and ultimately to twin 18-inch diameter culverts along the southwestern portion of the site that cross under Alleghany Road (Analysis Point 1). The second location of off-site discharge is located along the southern property line and represents runoff discharging to the I-90 roadside ditch (Analysis

Point 2). The roadside ditch along I-90 flows west and ultimately discharges to the twin culverts.

The third location of flow discharging off-site includes approximately 44 acres of the northern portion of the site that drains via overland flow to a ditch located along the eastern property boundary and flows north to a 36-inch culvert under Indian Falls Road (Analysis Point 3). The remaining off-site flow location is situated at the northwest corner of the site, along Indian Falls Road. Stormwater runoff from the northwestern portion of the site enters a 16-inch concrete pipe that conveys water north across Indian Falls Road (Analysis Point 4).

5.0 EROSION AND SEDIMENT CONTROL

5.1 Erosion and Sediment Control Practices

Erosion and Sediment Control Practices include, but are not limited to, the following:

Temporary Structural Controls Silt Fence Dust Control Stabilized Construction Entrance Check Dams Sediment Traps Sediment Basins Inlet Protection Temporary Swale Seeding

Permanent Structural Controls Grading

Temporary Non-Structural Controls (including vegetative practices) Seed and mulch bare soil areas within 14 days of disturbance unless construction will resume in that area within 21 days. If greater than 5 acres of soil is disturbed at any one time then soil areas shall be seeded and mulched within 7 days of where soil disturbance activity has temporarily or permanently ceased.

Permanent Non-Structural Controls (including vegetative practices) Seed and mulch all disturbed areas. Slopes that are 3:1 or steeper should receive a Rolled Erosion Control Product (RECP), sodding, and or hydro-seeding a homogenous mixture of wood fiber mulch with tackifying agent.

Refer to Construction Drawings attached in Appendix C for detailed information on each practice.

5.2 Erosion and Sediment Control Drawings

Erosion and Sediment Control drawings are included in Appendix C.

5.3 Construction Phasing Plan and Sequence of Operations

Full buildout of the project will be completed in seven (7) phases, with each new phase commencing approximately every ten years. Each new phase may potentially have sub-phases to limit disturbance to the earth and cemetery operations. Phase 1 will be constructed in three phases. The phases are referred to as Phase 1A (Early Turn Over), Phase 1B, and Phase 1C (Site Restoration).

Phase 1A and Phase 1B work may occur simultaneously. Phase 1A work will be required to be completed and stabilized within the time frame stated in the Construction Documents. Phase 1 is expected to impact more than five (5) acres at a single time. Written authorization from NYSDEC is required prior to disturbing greater than five (5) acres of soil at any one time. If granted, the following additional requirements shall be implemented per the SPDES General Permit:

Contractor shall prepare and submit to the RE/COR and Cemetery Director for approval, a Construction Sequencing Plan prior to construction.

The maximum area disturbed at any one time shall be restricted to 35 acres.

Temporary structural erosion controls must be installed prior to earthwork as per the attached plans.

A qualified inspect must conduct at least two (2) site inspections every seven

(7) calendar days, for as long as greater than five (5) acres of soil remain disturbed. The two (2) inspections shall be separated by a minimum of two

(2) full calendar days.

In areas where soil disturbance activity has temporarily or permanently ceased, the application of soil stabilization measures must be initiated by the end of the next business day and completed within seven (7) days from the date the current soil disturbance activity ceased. Soil stabilization measures selected shall be in conformance with the New York State Standards and Specifications for Erosion and Sediment Control, dated November 2016.

Temporary erosion control devices will not be removed until the area served is stabilized by the growth of vegetation and the area is certified as being stabilized by the Certified Inspector.

5.4 Erosion and Sediment Control Practice Maintenance

Temporary erosion and sediment control practices shall be maintained frequently during construction. It is the responsibility of the owner to retain the services of a qualified inspector to regularly inspect the effectiveness of the specified erosion and sediment controls. The qualified inspector shall notify the owner/operator and contractor of any deficiencies and maintenance needs. The owner/operator and contractor shall pay close attention to SWPPP Inspection Reports that will advise of needed maintenance, and the owner/operator shall be responsible for making sure maintenance activities are carried out. Temporary erosion and sediment control practice maintenance needs are listed below:

Silt fence –maintenance shall be performed as needed and material removed when “bulges” develop in the silt fence. When sediment material accumulates to one third of the silt fence height, the sediment will be removed and placed in an upland area and be stabilized. Any tears in the silt fence fabric will be repaired or replaced, any silt fence that is not properly toed in will be repaired and any broken posts will be replaced.

Check dams – should be inspected after each rain event. Correct all damage immediately. If significant erosion has occurred between structures, a liner of stone or other suitable material should be installed. Remove sediment accumulated behind the dam as needed to allow channel to drain through the check dam and prevent large flows over the dam.

Storm drain inlet protection (not including silt sacks) – inspect after each storm event. Remove sediment when 50 percent of the storage volume is achieved.

Sediment trap – sediment shall be removed and the trap restored to the original dimensions when the sediment has accumulated to ½ of the design depth.

Sediment basins- should be inspected for stability and integrity at least once every seven (7) days and especially after rain storms. Any structural failure in sediment basins or trenches that serve them shall be repaired within 24 hours after detection. All temporary sediment basins or trenches shall be cleaned out when one foot of sediment or half the design depth of the trap has accumulated. All spoils shall be removed to a stabilized upland area.

Stabilized construction entrance – entrance shall be maintained in a condition which shall prevent tracking. This may require periodic top dressing with additional aggregate. All sediment tracked onto or spilled on public rights of way shall be removed immediately. When necessary, wheels must be cleaned to remove sediment prior to entrance on public rights of way. When washing is required, it shall be done in an area stabilized with aggregate and wash water shall be directed away from streams or wetlands preferably to a broad grassed area or a stormwater pond.

Rock outlet protection – once a riprap outlet has been installed, the maintenance needs are very low. It should be inspected after high flows for evidence of scour beneath the riprap. Repair should be immediate.

Replace top-soil, mulch and seed where seeding has been disturbed.

Dust control – if the site is subject to dusty conditions on the construction access roads or other open areas, these areas will be have water or other suitable material applied that will inhibit the production of dust. This will be done on an as needed basis or preventatively if problems are known to occur.

No chemical or polymer materials should be applied in close proximity to any streams or wetlands.

5.5 Erosion and Sediment Control Inspections

It is recommended that a rain gage be installed at the site.

A qualified inspector shall conduct an assessment of the site prior to the commencement of construction and certify in an inspection report that the appropriate erosion and sediment controls described in this SWPPP and required by GP-0-15-002 have been adequately installed to ensure overall preparedness of the site for commencement of construction.

This qualified inspector must be a Licensed Professional Engineer, Certified Professional in Erosion and Sediment Control (CPESC), Registered Landscape Architect, or someone working under the direct supervision of, and at the same company as, the licensed Professional Engineer or Registered Landscape Architect, provided they have received 4 hours of NYSDEC endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other NYSDEC endorsed entity. After receiving the initial training, the qualified inspector shall receive 4 hours of training every 3 years.

The day-to-day erosion control activities on the site will be monitored by the construction manager. The qualified inspector will make at least one inspection every seven (7) days of erosion control devices, and non-stabilized areas during construction. When more than five (5) acres of soil is disturbed at any one time the qualified inspector will make at least two inspections every seven (7) calendar days, with each inspection separated by a minimum of two (2) full calendar days. A maintenance inspection report will be completed by the qualified inspector after each inspection. The report form to be completed by the inspector is attached in Appendix E. Completed inspection reports shall be compiled in Appendix E.

The qualified inspector shall contact the owner/operator at the conclusion of each inspection and inform the owner/operator that a new inspection report has been placed in the SWPPP. It is the owner/operator’s responsibility for addressing action items identified in the qualified inspector’s inspection reports in a timely manner.

All measures will be maintained in good working order; if repair is necessary, it will be initiated within 24 hours of report. The qualified inspector shall take photographs of any needed repairs and also photograph when the repairs are completed. These photographs will be time and date stamped and attached to the weekly inspection report that is put into Appendix E. When the repairs are made, photographs will be taken showing the repairs, and these “after” photographs will also be added to Appendix E directly following the “before photographs.

Seeded and planted areas will be inspected for bare spots, washouts, and healthy growth. If necessary, spot reseeding or sodding will be implemented.

A trained contractor will be an employee from the contracting company responsible for the implementation of the SWPPP. This person will be onsite when any soil disturbing activities are being conducted. The trained contractor must have received 4 hours of NYSDEC endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other NYSDEC endorsed entity. After receiving the initial training, the trained contractor shall receive 4 hours of training every 3 years. This trained contractor cannot conduct the regular SWPPP compliance inspections unless they meet the qualified inspector qualifications.

5.6 Contractor Sequence Form

The operator shall prepare a summary of construction status using the Construction Sequence Form (included in Appendix F) once every month. Significant deviations to the sequence and reasons for those deviations (i.e. weather, subcontractor availability, etc.), shall be noted by the contractor. The schedule shall be used to record the dates for initiation of different construction activities, implementation of erosion control measures, stabilization, etc. A copy of this table will be maintained in Appendix F.

6.0 POST CONSTRUCTION STORMWATER MANAGEMENT

PLANNING

6.1 Stormwater Model and Analysis

Stormwater modeling was performed using the computer program HydroCAD (version 10.00) produced by HydroCAD Software Solutions, LLC, and all stormwater calculations were completed utilizing the SCS TR-20 and TR-55 methods, widely accepted engineering practices, and recommended procedures listed in the NYSDEC Stormwater Management Design Manual.

6.2 Storm Events Analyzed

In conformance with the NYSDEC Stormwater Management Design Manual (SMDM), the following storms were analyzed:

1. The 90% rainfall event totaling 1 inch as per Figure 4.1 of the SMDM, used as the basis for Water Quality Volume treatment goals.

2. The 1-Year, Type II Design Storm having a 24-hour rainfall total of 1.80 inches as per Figure 4.4 of the Manual, used as the basis for Channel Protection Volume extended detention requirements.

3. The 10-Year, Type II Design Storm having a 24-hour rainfall total of 3.25 inches, as per Figure 4.5 of the Manual, used as the basis for meeting the Overbank Flood Control Criteria.

4. The 100-Year, Type II Design Storm having a 24-hour rainfall total of 5.50 inches as per Figure 4.6 of the Manual, used as the basis for meeting the Extreme Flood Control criteria.

6.3 Proposed Stormwater Runoff Conditions

Under the watershed’s Proposed Condition, all stormwater from the Project will continue to discharge to the same points as in the Existing Condition (Analysis Points 1-4), see Section 4.8 of this report for descriptions of the Analysis Points.

The total watershed has generally remained unchanged, as shown on the drawing “W-2 Proposed Conditions Watershed Map” contained in Appendix B.

6.4 Water Quality Volume Calculations

The required water quality volume (WQv) was calculated for each drainage area contributing to stormwater practices, based on the proposed design and subcatchment mapping. The Calculations were performed in accordance with the equation presented in Section 4.2 of the Manual, and the following tables summarize the required versus provided water quality volumes for Phases 1-5 the Project as well as the Future Phases:

Table 5-1 Water Quality Volume (WQv) Summary

Phases 1 - 5 SMP Type Required Provided

(ac-ft) (ac-ft)

SMP1 Wet Pond 0.232 0.246

SMP2 Stormwater Wetland 0.202 0.684

SMP3 Stormwater Wetland 0.187 0.456

SMP4 Pocket Pond 0.037 0.095

SMP5 Pocket Pond 0.034 0.108

SMP6 Pocket Pond 0.133 0.205

SMP7 Pocket Pond 0.022 0.073

SMP8 Pocket Pond 0.039 0.098

SMP9 Pocket Pond 0.076 0.131

SMP10 Pocket Pond 0.059 0.110

SMP11 Filter Strip 0.015 0.015

TOTAL 1.036 2.221

Table 5-2 Water Quality Volume (WQv) Summary

Future Phases SMP Type Required Provided

(ac-ft) (ac-ft)

SMP13 Pocket Pond 0.117 0.246

SMP14 Pocket Pond 0.094 0.096

TOTAL 0.211 0.342

6.5 Green Infrastructure Practices/Runoff Reduction Calculations

The proposed Green Infrastructure and Runoff Reduction practices on this project are listed below:

Conservation of Natural Areas Sheetflow to Riparian Buffers/Filter Strips Rooftop Disconnection Tree Planting/Tree Box

The project provides a runoff reduction volume (RRv) of 0.378 acre-feet. See Table 6-1 for a summary of the provided runoff reduction volumes for each green infrastructure practice respectively:

Table 6-1 Runoff Reduction Volume (RRv) Summary

Phases 1 - 5

SMP Provided

(ac-ft)

5.3.1 Conservation of Natural Areas 0.234

5.3.2 Sheetflow to Riparian Buffers/Filter Strips 0.120

5.3.3 Vegetated Open Swales 0.006

5.3.4 Tree Planting/Tree Box -

5.3.5 Disconnection of Rooftop Runoff 0.018

5.3.6 Stream Daylighting -

5.3.7 Rain Garden -

5.3.8 Green Roof -

5.3.9 Stormwater Planters -

5.3.10 Rain Tanks/Cisterns -

5.3.11 Porous Pavement -

TOTAL 0.378 (ac-ft)

The provided volume is less than the Water Quality Volume. As part of the stormwater management plan, the following green infrastructure planning and design options were evaluated and the corresponding specific site limitations:

5.3.1 Conservation of Natural Areas

o Conservation areas are proposed as part of this project.

5.3.2 Sheetflow to Riparian Buffers/Filter Strips

o Sheetflow to riparian buffers is proposed as part of this project.

5.3.3 Vegetated Open Swales

o A vegetated swale is used as part of this project.

5.3.4 Tree Planting/Tree Box

o Tree plantings have been proposed throughout the site but credit is not taken due to the low RRv credit (<0.001 ac-ft) provided.

5.3.5 Disconnection of Rooftop Runoff

o Rooftop disconnection is proposed as part of the project.

5.3.6 Stream Daylighting

o All subsurface storm sewer piping will be daylighted as soon as possible.

5.3.7 Rain Garden

o Rain gardens are typically applied for residential applications. The contributing drainage areas of project components exceed the maximum contributing area of 1,000 sf (for a rain garden), specified in The Manual.

5.3.8 Green Roof

o A green roof is not proposed as part of this project as it is not financially feasible.

5.3.9 Stormwater Planters

o Stormwater planters are not proposed as part of this project due to poor existing soils.

5.3.10 Rain Tanks/Cisterns

o Rain tanks/cisterns are not financially feasible.

5.3.11 Porous Pavement

o Porous pavement is not used due to poor on-site soils.

6.6 Minimum RRv based upon Hydrologic Soil Group

If the RRv is less than the required WQv, then the design must at a minimum, reduce a percentage of the runoff from impervious areas to be constructed on the site. The percent reduction is based on the Hydrologic Soil Group of the site, and is determined by the Specific Reduction Factor (S). Utilizing the Specific Reduction Factor the minimum runoff reduction volume required is 0.371 acre-feet. See Appendix B for calculations.

6.7 Water Quality Volume Treatment with Standard Practices

The following Standard Management Practices are utilized to address the remaining WQv after RRv techniques are applied:

Stormwater Wetlands Pocket Ponds Wet Ponds

Based on the data included above, WQv and RRv requirements have been met.

6.8 Hydraulic and Hydrologic Analysis

The program utilized for quantifying stormwater runoff rates and volumes was HydroCAD software (version 10.00), produced by HydroCAD Software Solutions, LLC. HydroCAD is a program for modeling the hydrology and hydraulics of stormwater runoff that is based on techniques developed by the Soil Conservation Service (TR-55). For a given rainfall event, these techniques are used to generate hydrographs throughout a given watershed and estimate runoff. Additional calculations employ SCS TR-20 methods, widely accepted engineering practices and recommended procedures listed in the NYSDEC Stormwater Management Design Manual.

The project site has been divided into different subcatchments and each subcatchment has been characterized in a model of the existing site conditions.

These conditions include slope, vegetative cover type, soil type and identified areas of concentrated flow.

Changes to the site resulting from the proposed development have been incorporated into the “proposed conditions” model. These include changes in slope and cover-type resulting from the addition of buildings or paving, grading, and subcatchment boundaries. The model then predicts the hydraulic and hydrologic effects of three design storms (SCS 24-hour Type II design storms for 1, 10, and 100-year frequency rainfall) under existing and proposed conditions.

Hydrologic/hydraulic analysis has been performed for structural components of the stormwater control system for the applicable design storms. Refer to Appendix B for detailed calculations.

6.9 Channel Protection Volume (CPv)

Channel Protection Volume (CPv) is achieved by a combination of volume reduction through green infrastructure practices and detaining the one-year, 24-hour storm event. Per Section 4.4 of the New York State Stormwater Management Design Manual, “volume reduction achieved through green infrastructure can be deducted from CPv.” The majority of the CPv is detained in the proposed stormwater management ponds. Per Section 4.4 of the SWMDM “an individual orfice may not be required for CPv at sites where the resulting diameter of the ED orifice is too small to prevent clogging.” A minimum 3” orifice with a trash rack is proposed at each of the stormwater management ponds to provide CPv.

Table 6-1

Channel Protection Volume (CPv) Summary SMP Type Required Provided

(ft3) (ft3)

SMP1 Wet Pond 3,809 11,367

SMP2 Stormwater Wetland 9,040 28,493

SMP3 Stormwater Wetland 9,987 21,637

SMP4 Pocket Pond 1,316 4,057

SMP5 Pocket Pond 1,400 3,769

SMP6 Pocket Pond 5,037 5,124

SMP7 Pocket Pond 827 950

SMP8 Pocket Pond 811 1,662

SMP9 Pocket Pond 1,607 1,735

SMP10 Pocket Pond 1,257 3,096

TOTAL 35,091 81,890

Table 6-2

Channel Protection Volume (CPv) Summary Future Phases

SMP Type Required Provided

(ft3) (ft3)

SMP13 Pocket Pond 3,524 11,367

SMP14 Pocket Pond 2,401 2,622

TOTAL 5,925 13,989

6.10 Comparison of Pre and Post Construction Stormwater Runoff

The following table summarizes the HydroCAD model results in Appendix B, and presents a comparison of pre and post-development peak discharge rates.

Pre Development Post Development 10 year, 24 hour storm (Qp) 40.25 CFS 33.16 CFS 100 year, 24 hour storm (Qf) 154.81 CFS 140.76 CFS

Based on the data included above, Peak Rate and Volume requirements have been met.

6.11 Post Construction Stormwater Management Drawings

Post construction stormwater management drawings are included in Appendix C. Post construction stormwater management drawings include the following:

Specific locations, sizes, and lengths of each post construction stormwater management practice Details of post construction stormwater management practices include dimensions, material specifications, installation details, and operation and maintenance requirements.

7.0 POST CONSTRUCTION STORMWATER MAINTENANCE

7.1 Maintenance to be Performed

The United States Department of Veterans Affairs will be responsible for the continuous upkeep and maintenance of all on-site post construction stormwater management facilities.

Post-construction maintenance for this project will consist of regular inspections of permanent stormwater management facilities and steep slopes. These maintenance procedures are essential to assure continual performance of the stormwater management practices on your site. During the inspection and any maintenance activity to the stormwater management practices, the responsible party should fill out an inspection and maintenance log (Appendix E) to record that it was done.

Stormwater Pond

Should be inspected twice a year and after heavy rain storms.

Any erosion or scour occurring in the pond, forebay or outlets shall be repaired and revegetated as needed.

Sediment removal in the forebay shall occur every five to six years or when

50% full.

Regular litter control to be performed as needed.

Mow grass when it reaches 4-6 inches in height as needed

Stormwater Wetland

Should be inspected twice a year and after heavy rain storms.

Any erosion or scour occurring in the pond, forebay or outlets shall be repaired and revegetated as needed.

Sediment removal in the forebay shall occur every five to six years or when

50% full.

Regular litter control to be performed as needed.

If a minimum vegetative cover of 50% in not achieved in the planted wetland after the second growing season, a reinforcement planting is required.

Catch Basins

Sediment removal with a vacuum truck should be done at least once a year, preferably after spring runoff and then in early fall, or when they are at 50% capacity, whichever comes first.

Any mechanical valves should be operated for inspection every two months.

Riparian Buffer or Filter Strip Channelization and erosion need to be identified and repaired promptly and bare areas seeded. If used, the level spreader should be checked and repaired as needed.

Any accumulated sediment deposited into these areas needs to be removed by hand or very carefully with small equipment. Any ground disturbance should be minimized.

Filter strips should be maintained as dense turf/riparian buffer. Area should be re-seeded as necessary.

8.0 CONSTRUCTION WASTE

Litter and Waste Materials: The site shall be patrolled for litter on a regular basis and collected litter shall be kept in a container until disposed of. All waste materials generated during construction will be disposed at a suitable landfill, or transfer station.

Hazardous Waste: The project will not be a generator of hazardous waste and it is not anticipated that any hazardous waste will be generated during construction. If there are any materials generated, a licensed hazardous waste carrier will be contracted to dispose the hazardous material at a suitable disposal site. If hazardous materials are discovered during construction, the work will be stopped until the issue is resolved.

Waste: Portable sanitary facilities will be made available to construction personnel and will be serviced regularly.

9.0 OFFSITE VEHICLE TRACKING

Excavation equipment involved with the construction will remain on the project site and will not regularly egress or ingress the site. Any trucks used to bring in materials or remove materials via municipal paved roads will do so over a stabilized construction entrance. If any off-site vehicle tracking occurs, the contractor will be directed to initiate, street sweeping program in the immediate vicinity of the site to keep the roads clean. If tracking onto the road is a daily occurrence, sweeping will be done as needed and at least a final time at the end of the day. The contractor will have a sweeper onsite or readily available during construction.

10.0 TEMPORARY STABILIZATION FOR FROZEN

CONDITIONS

The following temporary stabilization measures MUST be performed when construction is occurring during winter/frozen ground conditions. The following requirements do not supersede any other requirements of this SWPPP as they apply to non-frozen ground conditions.

Perimeter erosion control MUST still be installed prior to earthwork disturbance as per this SWPPP.

Any areas that cannot be seeded to turf by October 1 or earlier will receive a temporary seeding. The temporary seeding will consist of winter rye seeded at the rate of 120 pounds per acre (2.5 pounds per 1,000 square feet) or stabilized as per the temporary stabilization for winter construction/frozen conditions.

Any area of disturbance that will remain inactive for a period of 14 consecutive days MUST be mulched. This includes any previously disturbed areas that are covered with snow.

Mulch MUST consist of loose straw applied at the rate of 2 to 3 bales (90 to 100 pounds) per thousand square feet.

Mulch MUST be applied uniformly over the area of bare soil or bare soil that is covered with snow. For the latter condition, mulch MUST be applied on top of snow.

Using a tracked vehicle, mulch MUST be crimped into the bare soil/snow.

The tracked vehicle MUST be driven across the mulched areas in at least two directions to maximize crimping of mulch into the soil/snow.

If mulch gets blown off an area to a significant degree, the site inspector WILL require that an area be re-mulched in accordance with Items 2 through 5 above, and this area WILL be included on the inspection checklist for the next inspection.

If a particular area repeatedly experiences loss of mulch due to wind, then the inspector WILL require that an alternative method be used to secure the mulch in place. Such alternatives may include the use of netting, tackifier or other methods deemed appropriate by the inspector.

During periods when snow is melting and/or surface soils are thawing during daytime hours, mulched areas MUST be re-tracked (crimped) as per Item 5 above at least once every seven days, more frequently if directed by the inspector. Additional mulch may be required to obtain complete coverage of an area. Biodegradable erosion control matting may be required on steeper slopes.

Additional stabilization measures for non-frozen ground conditions described in this SWPPP WILL be implemented at the time deemed appropriate by the inspector.

During the winter season, if a site has been stabilized and soil disturbing activities have been suspended for the winter, weekly inspections can be suspended. However, monthly inspections must still be conducted. All normal weekly inspections must resume when soil disturbing activities resume.

11.0 SOIL RESTORATION

11.1 Soil Restoration Requirements

Excessively compacted areas and other areas where work will be done on the Project Site will have soil restoration applied as needed and as specified in the table below according to each specific task. A copy of “Deep Ripping and De-compaction, (DEC 2008) is provided in Appendix J and should be utilized as specified in the following table:

If compost amendment is required, 2 to 4 inches of screened compost will be incorporated into the soil.

Prior to application of the deep-ripping and de-compaction, the depth to bedrock or naturally occurring hardpan should be known so that the depth of tillage be adjusted according to those restrictive depths.

Soils with a slope that exceeds 10% will not have full soil restoration with deep-ripping and de-compaction due to potential for erosion from tilled soil.

Any soil tillage (deep or shallow) will not be done on soils that are excessively wet, as this will damage the soil.

Type of Soil Disturbance Comments/Examples

Minimal Soil Disturbance Preservation of Natural Features Areas where topsoil is stripped only-no change in grade Clearing and Grubbing

HSG A& B HSG C & D

apply 6 inches of topsoil

Aerate* and apply 6 inches of topsoil

HSG A& B HSG C & D

Aerate and apply 6 inches of topsoil

Apply full Soil Restoration**

Areas where Runoff Reduction and/or infiltration practices are applied

Keep construction equipment from crossing these areas. To protect newly installed practice from any ongoing construction activities construct a single phase operation fence area.

**Per "Deep Ripping and Decopmpaction, DEC 2008"

*Aeration includes the use of machines such as tractor-drawn implements with coulters making a narrow slit in the soil, a roller with many spikes making indentations in the soil, or prongs which function like a mini-subsoiler

Restoration not permitted

Restoration not required

Soil Restoration Requirement

Restoration not required, but may be applied to enhance the reduction specified for appropriate practices

Areas of cut and fill

Heavy traffic areas onsite (especially in a zone 5-25 feet around buildings, but not within a 5 foot perimeter around foundation walls)

Any tillage will not be done within approximately 10’ of the drip-line of any existing established trees.

Any large stones that are unearthed during tillage should be removed from the surface prior to final surface preparation and vegetation establishment.

When soil restoration is done in an area, any traffic will be prevented from driving across this area to prevent re-compaction of the area. This area will be seeded and mulched.

12.0 SPILL PREVENTION PRACTICES

12.1 Good Housekeeping and Material Management Practices

The following good housekeeping and material management practices will be followed on site during the construction project to reduce the risk of spills or other accidental exposure of materials and substances to stormwater runoff.

Materials will be brought on site in the minimum quantities required.

All materials stored on site will be stored in a neat, orderly manner in their appropriate containers, and if possible, under a roof or other enclosure.

Products will be kept in their original containers with the original manufacturer’s label.

Substances will not be mixed with one another unless recommended by the manufacturer.

Whenever possible, all of a product will be used up before disposal.

Manufacturer’s recommendations for proper use and disposal will be followed.

The construction manager or his designee will inspect regularly to ensure proper use and disposal of materials on site.

The contractor shall prohibit washing of tools, equipment, and machinery in or within 100 feet of any watercourse or wetland.

All above grade storage tanks are to be protected from vehicle damage by temporary barriers.

12.2 Inventory for Pollution Prevention Plan

The materials and substances listed below are expected to be on-site during construction.

Petroleum for fueling vehicles will be stored in above ground storage tanks.

Tanks will either be steel with an enclosure capable of holding 110% of the storage tank volume or of a Con-Store, concrete encased type typically employed by NYSDOT. Hydraulic oil and other oils will be stored in their original containers. Concrete and asphalt will be stored in the original delivery trucks.

Fertilizer may be stored on site in its original container for a short period of time prior to seeding. Original containers will be safely piled on pallets or similar devices to protect from moisture.

Paints and other similar materials will be stored in their original containers and all empty containers will be disposed of in accordance with label directions.

Portable sanitary facilities, which contain chemical disinfectants (deodorants) will be located on-site, with the disinfectants held in the tank of the toilet.

12.3 Hazardous Products

These practices are used to reduce the risks associated with hazardous materials.

Products will be kept in original containers unless they are not re-sealable.

Original labels and material safety data sheets will be retained; they contain important product information.

If surplus product must be disposed of, manufacturers’ or local and State recommended methods for proper disposal will be followed.

12.4 Spill Prevention

The following product specific practices will be followed on site.

Petroleum Products:

Construction personnel should be made aware that emergency telephone numbers are located in this SWPPP.

The contractor shall immediately contact NYSDEC in the event of a spill, and shall take all appropriate steps to contain the spill, including construction of a dike around the spill and placing absorbent material over this spill.

The contractor shall instruct personnel that spillage of fuels, oils, and similar chemicals must be avoided and will have arranged with a qualified spill remediation company to serve the site.

Fuels, oils, and chemicals will be stored in appropriate and tightly capped containers. Containers shall not be disposed of on the project site.

Fuels, oils, chemicals, material, equipment, and sanitary facilities will be stored/located away from trees and at least 100 feet from streams, wells, wet areas, and other environmentally sensitive sites.

Dispose of chemical containers and surplus chemicals off the project site in accordance with label directions.

Use tight connections and hoses with appropriate nozzles in all operations involving fuels, lubricating materials or chemicals.

Use funnels when pouring fuels, lubricating materials or chemicals.

Refueling and cleaning of construction equipment will take place in parking areas to provide rapid response to emergency situations.

All on-site vehicles will be monitored for leaks and receive regular preventative maintenance to reduce the chance of leakage. Any vehicle leaking fuel or hydraulic fuel will be immediately scheduled for repairs and use will be discontinued until repairs are made.

Fertilizers:

Fertilizer will be stored in its original containers on pallets with water resistant coverings.

Proper delivery scheduling will minimize storage time.

Any damaged containers will be repaired immediately upon discovery and any released fertilizer recovered to the fullest extent practicable.

Paints:

All containers will be tightly sealed and stored when not required for use.

Excess paint will not be discharged to the storm water system or wastewater system, but will be properly disposed of according to manufacturers’ instructions or State and local regulations.

Concrete Trucks:

Concrete trucks will be allowed to wash out or discharge surplus concrete or drum wash water only at designated locations on site.

Asphalt Trucks:

Asphalt trucks shall not discharge surplus asphalt on the site.

12.5 Spill Control Practices

In addition to the good housekeeping and material management practices discussed in the previous sections of this plan, the following practices will be followed for spill prevention and cleanup. The construction manager or site superintendent responsible for the day-to-day site operations will be the spill prevention and cleanup coordinator. He will designate at least three other site personnel who will receive spill prevention and cleanup training. These individuals will each become responsible for a particular phase of prevention and cleanup. The names of responsible spill personnel will be posted in the material storage area and in the onsite construction office or trailer.

Manufacturers’ recommended methods for spill cleanup will be clearly posted and site personnel will be made aware of the procedures and the location of the information and cleanup supplies. Any spill in excess or suspected to be in excess of two gallons will be reported to the NYSDEC Regional Spill Response Unit. Notification to the NYSDEC (1-800-457-7362) must be completed within two hours of the discovery of the spill.

Materials and equipment necessary for spill cleanup will be…