DPW_SWPPP_2022.pdf

TOWN OF SIMSBURY

STORMWATER POLLUTION PREVENTION PLAN (SWPPP)

66 Town Forest Road, Simsbury, CT

PREPARED FOR:

Town of Simsbury Department of Public Works 66 Town Forest Road Simsbury, CT

PREPARED BY:

Atlas Technical Consultants LLC 290 Roberts Street-Suite 301 East Hartford, CT 06108 June 29, 2023

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290 Roberts Street-Suite 301 East Hartford, CT 06108

(860) 282-9924 | oneatlas.com

June 29, 2023

Mr. Thomas J. Roy, PE Town of Simsbury, Department of Public Works 66 Town Forest Road Simsbury, CT

Subject: Stormwater Pollution Prevention Plan (SWPPP) 66 Town Forest Road, Simsbury, CT

Dear Mr. Roy, Atlas is pleased to present this Stormwater Pollution Prevention Plan (SWPPP) for the Town of

Simsbury, Department of Public Works.

If you have any questions, please call us at (860) 282-9924.

Respectfully submitted, Atlas Technical Consultants, LLC

Luke Whitehouse Kay Lehoux Environmental Division Manager Environmental Compliance Manager

Distribution: troy@simsbury-ct.gov

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CONTENTS

EMERGENCY CONTACT AND NOTIFICATION LIST

1. INTRODUCTION

2. FACILITY INFORMATION

2.1 Facility Information

2.2 Facility Description

2.3 Structures and Operations Potentially Exposed to Stormwater

2.3.1 Vehicle Equipment Maintenance/Washing

2.3.2 Fuel Dispensing Area

2.3.3 Outside Storage

2.3.4 Roof Drains and Vents

2.3.5 ASTs

2.3.6 Other Potential Pollutant Sources

2.4 Spill History

3. STORMWATER POLLUTION PREVENTION TEAM

3.1 Team Members and Individual Responsibilities

3.2 Team Responsibilities

4. STORMWATER MANAGEMENT

4.1 Facility Drainage

4.2 Control Measures

4.2.1 Good Housekeeping

4.2.2 Vehicle or Equipment Washing

4.2.3 Floor Drains

4.2.4 Roof Areas

4.2.5 Minimize Exposure

4.2.6 Sediment and Erosion Control

4.2.7 Management of Runoff

4.2.8 Preventative Maintenance

4.2.9 Spill Prevention and Response

4.2.10 Salt Storage

4.2.11 Future Construction

4.2.12 Non-Stormwater Discharges

4.3 Stormwater Monitoring Program

4.3.1 Schedules and Test Parameters

Sector Specific Monitoring Requirements Impaired Waters Monitoring Requirements

4.3.2 Sample Collection

4.3.3 Recordkeeping and Reporting Requirements

5. TRAINING, INSPECTIONS, AND RECORDKEEPING

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5.1 Training

5.2 Inspections

5.2.1 Routine Inspections

5.2.2 Stormwater Visual Inspections

5.2.3 Stormwater Comprehensive Site Compliance Evaluations

5.3 Recordkeeping

6. PLAN REVIEW AND AMENDMENT

7. IMPLEMENT ITEMS

Facility Management Approval

Connecticut P.E. Certification

Non-Stormwater Discharge Certification

TABLES

Table 1 – Emergency Contact and Notification List

Table 2 – Structures and Operations Potentially Exposed to Stormwater

Table 3 – Control Measures

Table 4 – Stormwater Sampling Parameters and Limits

Table 5 – Implementation Items

FIGURES

Figure 1 Site Locus

Figure 2 Site Plan

APPENDICES

Appendix A Certifications

Appendix B Inspection Logs and Forms

Appendix C Training and Plan Revision Logs

Appendix D Spill Documentation and Notification Form

Appendix E Stormwater Sampling Forms and Results

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EMERGENCY CONTACT AND NOTIFICATION LIST

Table 1 – Emergency Contact and Notification List

Spill Management Team

Name Title Office Cell

Thomas J. Roy, PE Director of Public Works 860-658-3222 860-982-3724

Kevin Clemens Highway Superintendent 860-658-3222

Federal, State, and Local Agencies

Town of Simsbury Fire Department Local Fire Department/Fire Marshal Patrick T. Tourville

911 860-658-1971

Town of Simsbury Police Department Local Police Department/Chief Nicholas Boulter

911 860-658-3101

Connecticut Department of Energy and Environmental Protection (CTDEEP)

CTDEEP 866-337-7745 (24 hr.) --

National Spill Response Center Spill Reporting 800-424-8802 (24 hr.) --

US EPA (Region 1) New England EPA Resource 617-223-7265 (24 hr.) --

Spill Response Contractors and Other Services

Environmental Services Inc. (ESI) Spill Cleanup 800-486-SPIL (7745)

University of CT Health Center (Farmington)

Human Health Hazards 860-298-8442 --

Atlas Technical Consultants, LLC (Atlas)

Consultant 860-282-9924 --

Kay Lehoux (Atlas) Environmental Compliance Manager

860-466-6002 860-933-9657

1. INTRODUCTION

This Stormwater Pollution Prevention Plan (SWPPP) has been prepared for the Town of Simsbury’s Public Works Garage (the “Facility”) located at 64 Town Forest Road in Simsbury, Connecticut (the “Site”). This SWPPP has been prepared in accordance with the Connecticut Department of Energy and Environmental Protection (CTDEEP) General Permit for the Discharge of Stormwater Associated with Industrial Activity (Stormwater General Permit), effective October 1, 2019, which requires a SWPPP.

The Stormwater General Permit is applicable if a facility meets both of the following qualifications:

1) The facility meets the definition of “industrial activity”. Under the Stormwater General Permit, “industrial activity” includes numerous Standard Industrial Classification (SIC) codes and descriptive categories ☒YES ☐NO

Facility SIC code (Section 5(c)(2)(A)): 9199 (Public Works Garage)

Sector of Industrial Activity: Sector G

2) The facility discharges stormwater that may come into contact with an “industrial activity”. Any stormwater associated with an “industrial activity” on site is included.

☒YES ☐NO

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As the Facility is a covered “industrial activity” and it conducts industrial activities of which are exposed to stormwater, it is required to register under the Stormwater General Permit and prepare a SWPPP.

This SWPPP describes the procedures, methods, and equipment used to prevent the contamination of stormwater. This SWPPP is intended to meet the planning requirements of the Stormwater General Permit and, as such, a copy of this SWPPP will be kept on Site at all times.

Industrial activities at the Facility includes vehicle/equipment maintenance, fuel dispensing, and salt storage.

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2. FACILITY INFORMATION

2.1 Facility Information

Name: Town of Simsbury Public Works Garage

Address: 66 Town Forest Road Simsbury, CT

Phone No.: 860-658-3222

Facility Operations: Municipal Public Works Garage

Owner: Town of Simsbury

Operator: Town of Simsbury

Primary Contact: Thomas J. Roy, PE, Director of Public Works 860-658-3222

Alternate Contact: Kevin Clemens, Highway Superintendent 860-658-3222

2.2 Facility Description

The Site is located on a parcel of land approximately 37.19 acres and owned by the Town of Simsbury.

The property is mainly utilized for vehicle maintenance and repair, vehicle and equipment storage, fueling stations, salt storage, processed stone and clean fill storage, and clean sand processing. The public works office/garage is located in the southern and central portion of the property and surrounded by asphalt parking. Operations conducted at the Site occur over approximately 14.66 acres on the central portion of the property. The northern portion of the property includes undeveloped woodlands.

Five (5) buildings are present on the Subject Property. Building 1 (located along the southwestern corner and referred to as “Buildings and Grounds”) is utilized as a servicing building. Building 2 (located in the south-central border of the site and referred to as “Highway Garage”) is utilized for office space and vehicle maintenance and repair. Building 3 (located central and north of Building 2 and referred to as “Fleet Storage Building”) is utilized for equipment and vehicle storage as well as vehicle painting.

Building 4 (central and north of Building 3 and referred to as “Highway Truck Wash” and the former salt storage shed) is utilized as a truck wash. Building 5 (central and north of Building 4, and referred to as “Salt Storage”) is utilized for the storage of road salt.

Outside storage areas include areas for storing trailers, plows, miscellaneous construction equipment, and material storage piles (screen sand/soils). Double-contained, aboveground fuel storage tanks (ASTs) are present east of Buildings 2 and 3. Fueling operations of the service fleet takes place at these fuel ASTs.

Figure 1 depicts the site area; Figure 2 depicts the Site property and associated stormwater features.

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2.3 Structures and Operations Potentially Exposed to Stormwater

The following table describes the activities at the Site of which may be exposed to precipitation.

Table 2 – Structures and Operations Potentially Exposed to Stormwater

Activity Location Potential Pollutants Materials Management

Practices

Interior

Vehicle Equipment Storage/ Maintenance Buildings 1, 2, 3 Hydrocarbons, oil and grease, fluids

Activities conducted inside buildings on impervious areas. Spill response equipment stored nearby.

Vehicle Storage Building 3 Hydrocarbons, oil and grease, fluids, salt residue (sodium, chloride, cyanide)

Vehicles are stored inside when not in use and/or under maintenance. No vehicles are maintained outside.

Vehicle Washing Building 4 Hydrocarbons, oil and grease, fluids, salt residue (sodium, chloride, cyanide), total suspended sediment (TSS), total dissolved sediment

(TDS).

Building 4 equipped with floor trench drains that lead to an oil/grit/water separator.

Salt Storage Building 5 Sodium, chloride, cyanide, TSS, TDS, fugitive dusts

Salt storage and mixing activities conducted inside Building 5.

Exterior

Fuel Dispensing & ASTs Northern and northwestern portion of the active area of the Site.

Hydrocarbons Fuel dispensing occurs on impervious surfaces. Spill response equipment is located nearby.

Sand and Processed Stone Products Northwestern portion of the active area of the Site.

TSS, fugitive dusts Processed crushed stone materials are stored on concrete block storage bins, east of Buildings 4 & 5. The material in these bins is considered inert. Underlying soils are sands, which have high infiltrative capacity.

Sand, stone, clean fill loading/unloading Northwestern portion of the active area of the Site.

TDS, salts, fugitive dusts

Areas where sand, stone, and clean fill are loaded/unloaded are underlined with sand and gravel, allowing for infiltration of stormwater runoff into the underlying soils.

Sand/fill screening and loading operations Northwestern portion of the active area of the Site.

TSS, fugitive dusts Areas where sand is processed are underlined with sand and gravel, allowing for infiltration of

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The subsections below discuss the activities in the table above and others at the Site, which could potentially cause stormwater pollution.

2.3.1 Vehicle Equipment Maintenance/Washing

2.3.2 Fuel Dispensing Area

2.3.3 Outside Storage

stormwater runoff into the underlying soils.

Construction Equipment (conveyors, screeners, trailers, dump trucks, salt spreaders/hoppers, plows)

Central, western portion of the active area of the Site.

Oil and grease, fluids, hydrocarbons, salt residue, TSS

Maintains equipment in good operating order in an effort to minimize leaks of fluids or hydrocarbons from the equipment. Building 4 is utilized in periodically removing salt residue and

TSS.

Impounded Vehicle Storage Southeastern corner of the active area of the Site.

Oil and grease, fluids, hydrocarbons

Impounded vehicle fluids are empty prior to storage on-site.

On-site Waste Disposal Practices

Disposal of used motor oil, antifreeze, solvents, etc.

Interior of Buildings 1, 2, 3

None-Not exposed to precipitation

Activities conducted inside buildings on impervious areas. Spill response equipment stored nearby.

Solid Waste Dumpsters Central, western portion of the active area of the Site.

Total metals, TSS Dumpsters are equipped with closing lids, and drain plugs are intact.

Vehicle equipment maintenance is conducted inside Buildings 1 and 2. Vehicles and equipment are stored inside Building 3. Vehicle washing is conducted inside Building 4, where floor drains are connected to a 5,000-gallon oil/grit/water separator that discharges to municipal sewer. This oil/grit/water separator is cleaned on an annual basis.

There is one (1) fuel dispensing area at the Site, located along the eastern side of the active portion of the parcel, east of Buildings 2 and 3. Gasoline and diesel from the gasoline/diesel fuel ASTs are dispensed to Town and emergency vehicles in this area.

Outside storage areas consists of clean fill, screening equipment, sand, and processed stone.

Equipment stored outside throughout various locations onsite is maintained in good condition to minimize leaks and/or spills. The underlying soils of these outside storage areas consist of sand and gravel, allowing for stormwater infiltration.

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2.3.4 Roof Drains and Vents

2.3.5 ASTs

2.3.6 Other Potential Pollutant Sources

2.4 Spill History

Per the Stormwater General Permit, spills and leaks of 5 gallons or more of toxic or hazardous substances that occurred at the facility since April 2010 should be included in the facility spill history.

The buildings are equipped with roof drains. The drains discharge to the pavement via downspouts.

Stormwater on pavement sheet flows to catch basins located throughout the paved area. The catch basins then direct stormwater to a retention basin, located north of Building 5, or to the water quality unit, located along the southeastern corner of the active portion of the Site.

A 1,500-gallon waste oil AST and a 500-gallon waste oil/antifreeze AST are located along the western side of Building 2 and under an overhang. These ASTs are double-walled with integrated monitoring systems. Only trained employees are allowed to fill these ASTs. Two (2) magnesium-chloride totes (2,000-gallons each) are located along the southern side of the Building 4, under an overhang. Spill kits are located nearby for incidental spills. Other ASTs and 55-gallon drums are located inside Buildings 2, 3and 4, and are not exposed to precipitation. Spill kits are located nearby for incidental spills onto impervious areas. Two (2) 10,000-gallon ASTs (gasoline and diesel) are located on the eastern side of the site and are utilized for fueling activities. These ASTs are double-walled with integrated monitoring systems. Only trained employees are allowed to utilize these ASTs. Only competent personnel supervised by on-site staff are allowed to fill these ASTs.

A source of water is available in the sand processing area, located west of Building 4. If fugitive dusts are in excess, the processing operations utilize this water source for dust control, taking particular care to use water sparingly.

The Site has not had any reportable spills during the period of operation at the Site.

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3. STORMWATER POLLUTION PREVENTION TEAM

3.1 Team Members and Individual Responsibilities

The Stormwater Pollution Prevention Team at the Facility includes the following members.

Thomas J. Roy, PE, Team Leader Director of Public Works Telephone Number: 860-658-3222 (office); 860-982-3724 (cell) Responsibilities: Coordinate all stages of Plan development, inspections and implementation; coordinate training program; keep all records and ensure appropriate submittals; and oversee sampling program.

Kevin Clemens, Crew Leader Highway Superintendent Telephone Number: 860-658-3222 (office); 860-371-5883 (cell) Responsibilities: Assist the Team Leader with implementation of the Plan.

3.2 Team Responsibilities

The Stormwater Pollution Prevention Team is familiar with all aspects of this plan and facility processes and activities, as well as the location of and characteristics associated with oil and chemical substances handled and stored at the Facility. They are also familiar with the location of records pertinent to the SWPP Plan within the facility and the facility layout.

The Team is responsible for Plan development, maintenance, and implementation. Team responsibilities include:

1. Develop and implement Control Measures inspection and review procedures;

2. Conduct or oversee regular compliance inspections of the facility and assure documentation and review of these inspections;

3. Review analytical data from storm events for compliance with regulations;

4. Review new construction or facility modifications or changes, as necessary;

5. Make changes in procedures, as necessary, and proper notifications, if required; and

6. Update or revise the SWPPP, as necessary.

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4. STORMWATER MANAGEMENT

Section 4.0 presents a description of stormwater management at the Site and stormwater procedures implemented by facility personnel. This section is divided into three subsections, which discuss (1) Facility

Drainage, (2) Control Measures, and (3) Stormwater Monitoring. These subsections are presented below.

4.1 Facility Drainage

4.2 Control Measures

4.2.1 Good Housekeeping

4.2.2 Vehicle or Equipment Washing

4.2.3 Floor Drains

Stormwater generated on the roof of the buildings drains to the pavement below via roof drains.

Stormwater generated on the paved areas sheet flows to catch basins located on-Site. The roof drains or sheet flow discharges to the paved areas, where water is directed into catch basins.

Typically, stormwater generated on paved areas of the property flows along the natural contours, curb lines, and gradient of the surface towards catch basins.

Drainage Area 1 consists of the eastern side of Building 2, Building 3, Building 5, Building 5, outdoor storage of crushed stone and material storage, a fueling station, and the storage of liquid salts.

Materials stored outside are under cover and within secondary containment. Fueling is conducted by trained personnel only, and a stocked spill kit is kept nearby. Stormwater runoff in material storage areas typically infiltrates into the permeable underlying sands. A retention basin is located on the northern-most portion of Drainage Area 1 and is utilized to slow sediments and solids from entering into the Site’s stormwater system. There are 12 catch basins in Drainage Area 1. These catch basins are periodically inspected, and cleaned/maintained as needed. A water quality unit (WQU) (Model # 6040WQA) is located in Drainage Area 1 and is utilized to filter sediment prior to discharge at DPW- OF-1. Following discharge from the outfall, stormwater enters into Stratton Brook.

Drainage Area 2 consists of Building 1 (Building and Grounds) and paved areas, as well as a small portion of unpaved areas. Outdoor operations included in Drainage Area 2 include miscellaneous equipment and materials storage, as well as screening operations. Stormwater runoff in these areas typically infiltrates into the permeable underlying sands. There are nine (9) catch basins associated with this drainage area. Six (6) catch basins collect stormwater and connect directly to catch basins located on Town Forest Road, ultimately discharging into DPW-OF-1. ASTs in Drainage Area 1 are covered and within secondary containment.

Good housekeeping is used to maintain a clean and orderly workplace and to reduce the potential for accidental spills or releases of materials that could contaminate stormwater. Garbage and waste materials are store inside and properly disposed in a timely fashion.

Vehicles and equipment are washed inside the Building 4 in areas where wash water will enter the floor trench drains leading to the 5,000-gallon oil/grit/water separator. Washing of vehicles or equipment out of doors is prohibited.

Floor drains inside on-site buildings are associated with restrooms that discharge to the sanitary sewer.

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4.2.4 Roof Areas

4.2.5 Minimize Exposure

4.2.6 Sediment and Erosion Control

Roof drainage discharges to the pavement surrounding the buildings.

All vehicle maintenance operations are performed inside the buildings at the Site. Public Works vehicles/equipment are typically stored inside buildings overnight, or on permeable surfaces (sand). All vehicle repairs/maintenance will be performed indoors.

All containers with a capacity of 100-gallons or less are stored inside the buildings. The Site stores equipment and materials inside, including oils, greases, fluids, etc., In addition, these materials are stored in areas that provide secondary containment.

The majority of runoff in unpaved areas of the Site will infiltrate into the underlying sandy soils.

Runoff in graded areas is directed into the water quality detention basin, located north of Building 5. This detention basin reduces the amount of suspended solids and sediments discharging into the unnamed stream. Periodically, maintenance will be performed on the detention basin, including the removal of excess sediment, grading (if necessary), and the limiting of large vegetative growth (ex. Phragmites, cattails). If large vegetative growth is present, it should be limited to 10% or less of the basin.

The paved areas of the Site are generally flat, with gentle slopes towards catch basins. It is not likely that these areas pose an erosion risk. Paved areas should be swept regularly (at a minimum of monthly) to remove accumulated sediments. As part of the Comprehensive Site Compliance Evaluation, Site personnel inspect vegetated and non-vegetated areas to assure that soil erosion does not become an issue.

A water quality unit is located on the southeastern corner of the Site and is utilized for stormwater treatment (infiltration) on-site. The discharge point from this water quality unit is located south and across Town Forest Road, discharging to Stratton Brook

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4.2.7 Management of Runoff

4.2.8 Preventative Maintenance

For the purposes of this plan, runoff management is defined as practices which divert, infiltrate, reuse, or treat stormwater runoff. The outskirts of the Site utilize infiltration practices for stormwater. The stormwater detention basin located north of the Building 5 controls sediment utilizing a riprap spillway to slow sediments and silt. Native grasses and plants are also utilized to slow and trap sediments. Stormwater entering into this basin ultimately discharges into a nearby catch basin. The detention basin and on-site catch basins are periodically inspected and cleaned of accumulated sediments and solids.

A WQU is located on the southeastern corner of the Site. This WQU is designed to capture the majority of runoff and trap pollutants, particularly sediment and solids. This water quality unit is cleaned once a year, and periodically inspected. Stormwater is then discharged from the WQU into Stratton Brook via an outfall and rip rap swale.

Site equipment, including the ASTs, fuel dispensers, associated piping, pavement, etc., are regularly inspected for any signs of wear and tear. Items are appropriately repaired or replaced as needed.

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4.2.9 Spill Prevention and Response

4.2.10 Salt Storage

4.2.11 Future Construction

The Stormwater Pollution Prevention Team is the designated group accountable for spill prevention at the facility. These people are identified in Section 3 of this plan. The Town of Simsbury maintains a Spill Prevention, Control, and Countermeasure (SPCC) Plan, which details the oil storage and containment and spill prevention measures at the Site. This plan is under separate cover and is maintained in the office of the Site Director. Procedures for spill reporting and recordkeeping are contained within the SPCC Plan.

All oil or hazardous substances are stored in structures or areas equipped with secondary containment and/or spill response equipment. These structures are designed to contain released material and prevent releases from traveling beyond the property boundaries. Travel of a spill outside of secondary containment or off-site is not likely unless the secondary containment structures also fail.

A chain reaction of failures is not considered probable. As mentioned in Section 4.1, much of the property at the Site is relatively flat and paved. As such, in the event of a small release outside of containment, spilled product from a tank or container would likely pool in the vicinity.

However, larger releases could flow off-site. In the event of larger releases, a nearby spill kit will be utilized to surround the spill and/or nearby catch basins.

Pollution Prevention Team will immediately notify the CT DEEP by calling 866-337-7745. If requested by CT DEEP, the DPW, with the assistance of Atlas, will prepare and submit to the CT DEEP a completed “Report of Petroleum or Chemical Product Discharge, Spillage, or Release”. This Report should be submitted within 48 hours of discovering the release. A copy of the Report and instructions for completing it are provided in Appendix D.

If the spill violates applicable water quality standards, causes a film or sheen on, or discoloration of surface water, or causes a sludge or emulsion to be deposited beneath the surface of the water, then the Town of Simsbury DPW will immediately notify the National Response Center (NRC) at 800-424-8802. Refer to Appendix D for more information.

Additionally, should a spill event occur at the Site, the Stormwater Pollution Prevention Team would complete the Corrective Action Log and record the details of the incident.

Salt is stored inside Building 5, located north of Building 4.

Any future construction activity that disturbs greater than one (1) acre will be conducted in accordance with CT DEEP regulations and will comply with the 2002 Connecticut Guidelines for Soil Erosion and Sediment Control during construction, and the 2004 Connecticut Stormwater Quality Manual for the design and implementation of post-construction stormwater management measures. The facility will avoid, wherever possible, the use of copper or galvanized roofing or building materials for any new building construction where these materials will be exposed to stormwater.

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4.2.12 Non-Stormwater Discharges

Table 3 contains a summary of the potential pollutant sources at the Site and how some of the Control Measures discussed above apply to each.

Table 3 – Control Measures

4.3 Stormwater Monitoring Program

The Stormwater General Permit specifies required stormwater monitoring. The site has met all benchmark requirements for stormwater sampling. The stormwater monitoring program for the Site is as follows, and has been provided for informational purposes only.

4.3.1 Schedules and Test Parameters

The Stormwater General Permit requires semi-annual testing and specifies the parameters to be analyzed in the stormwater outfall sample. The following Table 4 summarizes the parameters to be tested for in the stormwater sample collected from the outfall.

The facility is subject to effluent limitations □ YES NO

Stormwater from the facility discharges to the following waterbody ........................................ Stratton Brook

The area of this waterbody to where stormwater from the Facility discharges is designated as an impaired waterbody.

□ YES NO

This waterbody is impaired due to the presence of the following contaminants.

Potential Pollutant Source

Good Housekeeping Minimize Exposure Spill Prevention

Vehicle Equipment- Maintenance/ Washing

Maintain area in reasonable clean condition.

Ensure trench drains, oil/grit/water separator, and associated piping are periodically cleaned out

Perform inside buildings only

Maintain spill response equipment nearby

Fuel Dispensing Maintain area in reasonable clean condition

All ASTs are clearly labeled

Minimize fuel transfers during rain events

Do not overfill vehicles.

Monitor all product transfer events.

Assure integrity of fuel dispensing equipment.

Maintain spill response equipment nearby.

Salt Storage Maintain area in reasonably clean condition

Store inside building Sweep paved areas periodically

The stormwater drainage system at the Facility was observed by Atlas in the spring of 2023 to determine if there were any non-stormwater-related discharges occurring. No non-stormwater discharges occur at the Site.

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Table 4 – Stormwater Sampling Parameters and Limits

SECTOR SPECIFIC MONITORING REQUIREMENTS

The sector specific monitoring requirements and associated benchmarks are as follows for Sector G where incidental soil de-icing material (salt) is stored:

Parameter

Chloride

Cyanide

These parameters are to be sampled for the first two (2) years of the permit term (four samples events).

IMPAIRED WATERS MONITORING REQUIREMENTS

Any potential discharge through the outfall would reach Stratton Brook. The portion of the Stratton Brook near the Site is not considered an impaired waterway.

Sampling Parameter1 Regulatory Criteria Sampling Frequency

S.U.2

Uncontaminated Rainfall pH NE3 Semi-Annual4

Stormwater pH 5-9 Semi-Annual mg/L5

Total Copper 0.059 Semi-Annual

Total Lead 0.076 Semi-Annual

Total Zinc 0.160 Semi-Annual

Total Suspended Solids 90 Semi-Annual

Total Oil and Grease 5 Semi-Annual

Chemical Oxygen Demand 75 Semi-Annual

Total Phosphorus-P 0.40 Semi-Annual

Total Kjeldahl Nitrogen 2.30 Semi-Annual

Nitrate-N 1.10 Semi-Annual

Aquatic Toxicity LC50≥50%6 Annual7

Notes:

1. All parameters listed in table are Standard Monitoring Benchmarks unless otherwise noted.

2. SU = Standard Units

3. NE = None Established

4. The semi-annual monitoring periods are October 1 to March 31 and April 1 to September 30.

5. mg/L = milligrams per liter

6. The 48-hour Acute Toxicity LC50 value (% Survival) must be greater than 50%.

7. Aquatic Toxicity monitoring is required annually for the first two (2) years of sampling. The monitoring period is October 1st to September 30th.

Not applicable. The receiving waterbody is not impaired.

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4.3.2 Sample Collection

Sampling should be conducted according to the following criteria.

1. Sampling is to be conducted during a storm event generating a stormwater discharge that occurs at least 72 hours after any previous storm event that generated a stormwater discharge. This is referred to as a qualifying event.

2. Monitoring events are to be separated by at least 30 days.

3. Grab samples are to be used for all monitoring. Grab samples are to be collected within the first 30 minutes of a storm event discharge.

4. All samples must be taken during the same storm event, if feasible.

5. Stormwater discharge containing snow or ice melt may be used, but must be noted on the sample reporting form.

For each storm event monitored, the following information is collected.

1. The date, discharge temperature, time of the start of the discharge, time of sampling at each outfall and magnitude (in inches) of the storm event sampled; and

2. The duration between the storm event and the end of the previous stormwater discharge event.

The following outline describes the stormwater sample collection and laboratory testing procedures followed for the outfall.

1. Collect the samples directly from the outfall. Fill the collection containers with stormwater without touching the insides of the containers. Cover the containers when finished.

2. Label all samples and store samples in a cooler or refrigerator at 4o C.

3. Prepare a Chain of Custody and transport the samples to the laboratory as soon as possible (less than 24 hours after sampling).

4. Unless otherwise specified in the Stormwater General Permit, all pollutant parameters must be tested according to methods prescribed in 40 CFR 136.

5. Acute toxicity biomonitoring tests must be conducted according to the procedures specified in Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, 5th edition (EPA 821-R-02-012).

4.3.3 Recordkeeping and Reporting Requirements

For each stormwater sample taken, the following information is recorded.

1. The place, date and time of sampling;

2. The person(s) collecting the samples;

3. The dates and times the analyses were initiated;

4. The person(s) or laboratory who performed the analyses;

5. The analytical techniques of methods used; and

6. The results of all required analyses.

A log for recording this data is presented in Appendix C.

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After collection of four (4) semi-annual samples, if the average of the four (4) monitoring values for any parameter does not exceed the benchmark, the monitoring requirements for that parameter have been fulfilled for the term of the Stormwater General Permit. Once the benchmark for sample pH has been met and monitoring for pH has been fulfilled, the measurement of rainfall pH is no longer required.

Within 120 days of receiving the results of the fourth semi-annual sample, if the average of the four (4) semi-annual monitoring values for any parameter exceeds the benchmark, the Town will review the selection, design, installation, and implementation of the Control Measures to determine if modifications are necessary to meet the benchmarks, and either:

Make the necessary modifications to the Control Measures and SWPP Plan and continue semi-annual monitoring until four (4) consecutive semi-annual monitoring events have been completed for which the average does not exceed the benchmark;

or

Make a determination that no further pollutant reductions are technologically available and economically practicable and achievable in light of best industry practice to implement additional control measures or meet the benchmarks, in which case the Facility must continue monitoring once per year. The Site will also document the rationale for concluding that no further pollutant reductions are achievable and submit this documentation to the CT DEEP for written approval. The Site will retain all records related to this documentation with the SWPPP.

If an exceedance of the four (4)-event, average is mathematically certain, the Site will review the control measures and perform any required corrective action immediately or document why no corrective action is required, without waiting for the full four (4) monitoring events. If, after modifying the control measures and conducting additional semi-annual monitoring, the average of the most recent four (4) monitoring events still exceeds the benchmark, or if an exceedance of the benchmark by the 4-event average is mathematically certain for the most recent four (4) monitoring events, the Site will again review the control measures and take one of the two actions above.

The CTDEEP has established a Stormwater Monitoring Report (SMR) Form that is to be completed and submitted for each outfall sampled. Monitoring results are submitted to the CTDEEP within 90 days of the date of the sampling. If a discharge does not occur during a monitoring period, a SMR must still be submitted, and a notation of “No Discharge” will be made on the form.

A signed and dated original of the SMR Form is submitted to the CT DEEP at the following address:

Water Toxics Program Coordinator Bureau of Water Protection and Land Reuse Department of Energy & Environmental Protection 79 Elm Street Hartford, CT 06106-5127

A sample copy of an SMR is found in Appendix E. Copies of the completed SMRs may be kept in Appendix E. If the Site monitors its stormwater more frequently than required by the Stormwater General Permit, it will also report those results to the CTDEEP.

At this time, the Site has met all sampling requirements and is not required to submit an SMR to

CTDEEP.

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5. TRAINING, INSPECTIONS, AND RECORDKEEPING

This section of the SWPPP describes the Training, Inspections, and Recordkeeping procedures for the Site. Appendix C contains recordkeeping log forms for inspections and recordkeeping log forms for training and Plan revisions. All records of inspections, training and Plan revisions are maintained by the Stormwater Pollution Prevention Team and may be kept with the SWPPP.

5.1 Training

All training will be held on an annual basis. Any personnel associated with Site operations or product handling at the Site is required to attend the training.

The training topics include the following items:

1. Instructions on the contents of this SWPP Plan.

2. Discussion of the Stormwater Pollution Prevention Team and its responsibilities.

3. A review of the proper Control Measures to be used by employees on a regular basis, including spill prevention and response; standard housekeeping measures; and materials and waste handling procedures.

4. A review of the most recent stormwater Comprehensive Site Compliance Evaluation results and any resulting changes to the SWPP components of this Plan.

5.2 Inspections

The Stormwater Pollution Prevention Team is responsible for the entire Site and its proper operation. Site inspections are conducted by at least one member of the Team or by a qualified professional.

Inspection logs for this SWPPP have been developed for the Site. The logs are designed to meet the inspection requirements of the Stormwater General Permit regulation. A copy of the logs is presented in Appendix B with a table summarizing this inspection schedule. Records of inspections are maintained by the Stormwater Pollution Prevention Team and may be kept with the SWPPP. The sections below describe the components of the Site inspections.

5.2.1 Routine Inspections

On a monthly basis, at least one member of the Stormwater Pollution Prevention Team or someone designated by it conducts a walkthrough of the Site. At a minimum, the outdoor storage tanks, and fuel dispensing areas are inspected to ensure that all equipment and structures are in a satisfactory condition.

Routine Facility Inspections Forms can be found in Appendix B.

5.2.2 Stormwater Visual Inspections

Visual inspections of stormwater are conducted quarterly throughout the period of Stormwater General Permit coverage. For monitoring purposes, quarters will begin on January 1, April 1, July 1, and October 1.

Inspections are conducted during a qualifying rain event. If no qualifying rain event occurs during the quarter, a letter will be entered into the file documenting such. Visual monitoring of stormwater is conducted during the first 30 minutes of the rain event. The examination documents observations of color, odor, clarity, floating solids, settled solids, suspended solids, foam, oil sheen and other obvious indicators of stormwater pollution. The inspection is documented. The inspection form is presented in Appendix B.

If the visual assessment indicates the Control Measures for the Site are inadequate or are not being properly operated and maintained, the Town will review and revise the selection, design, installation, and implementation of the Control Measures to ensure that the condition is eliminated and will not be repeated in the future. Record of this documentation will be maintained in the SWPPP.

Page | 17

5.2.3 Stormwater Comprehensive Site Compliance Evaluations

Comprehensive Site Compliance Evaluations are conducted every six months at the Site by one or more persons either on the Stormwater Pollution Prevention Team or designated by the team. All potential sources of pollution identified in Section 2.2 of this Plan are inspected to assure that appropriate Control Measures (Section 4.2) are implemented. Any modification, including the elimination, movement, or creation of an exposed area or pollution source, is documented. The SWPPP is updated to reflect this information as needed.

The semi-annual inspections are conducted, when possible, during a rainfall event. The Comprehensive Site Compliance Evaluation Form is presented in Appendix B. Any deficiencies observed during the evaluation are noted on the form.

Within thirty days of the inspection, follow-up actions are taken to correct any deficiencies. If the corrections cannot be made within the thirty-day period, a schedule for implementation of the corrections is added to the SWPPP within the thirty-day period. The Form and/or follow-up actions are maintained by the Stormwater Pollution Prevention Team.

5.3 Recordkeeping

This SWPPP and all training, inspection, recordkeeping and testing records associated with it are maintained at the Site for a minimum of five years following the expiration of the Stormwater General Permit.

Records are signed by an appropriate supervisor, where applicable. Modifications to this Plan are recorded in the Revisions Log in Appendix C.

Page | 18

6. PLAN REVIEW AND AMENDMENT

Atlas recommends that this Plan be reviewed at least annually by the Stormwater Pollution Prevention Team to verify that it represents current facility conditions and complies with current regulations. During this review, the Town of Simsbury should check with a qualified environmental consultant or the CTDEEP to verify that the most current governing regulations are incorporated.

The Town will amend this Plan within 120 days whenever the Site experiences any of the following conditions:

a substantial change which has a significant effect on the discharge, or potential for discharge, of pollutants in stormwater from the Site;

an inspection, investigation or monitoring event which shows that the SWPPP is not effectively controlling or eliminating pollutants in stormwater discharges;

a failure of the SWPPP to ensure or adequately protect against pollution of the waters of the state;

a request by the Commissioner of the CTDEEP to modify the SWPPP; or a notification that they are subject to requirements because the receiving water to which it discharges stormwater has been designated as impaired under Section 303(d) of the Clean Water Act and as identified in the most recent State of Connecticut Integrated Water Quality Report, or a TMDL has been established for the receiving water.

These amendments will be effective when re-certified by a Professional Engineer licensed to practice in Connecticut or a Certified Hazardous Materials Manager and will be recorded in the Revisions Log included in Appendix A.

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7. IMPLEMENT ITEMS

The following recommendations have been made based on Atlas’s site inspection a SWPPP review conducted by the certifying Professional Engineer

Table 5 – Implementation Items

Recommendations Completed

Date Initials

Review the SWPP Plan at least bi-annually to verify that it represents current facility conditions and complies with current regulations.

I

FIGURE 1

SITE LOCUS

290 Roberts Street, Suite 301 East Hartford, CT. 06108 860-282-9924

USGS Topography Map

DESIGNED BY: KLL SCALE: NTS

DRAWN BY: KLL DATE: 6/2023 Figure 1

REVIEWED BY: DPB

SOURCE: USGS Topographic Map, Avon, Connecticut, Quadrangle, 7.5 Minute Series, dated 2021.

Project: Town of Simsbury DPW Client: Town of Simsbury

Site Address: 66 Town Forest Road Simsbury, Connecticut

Site Locus

Site

FIGURE 2

SITE PLAN

APPENDIX A

CERTIFICATIONS

Facility Management Approval

I certify under penalty of law that this document and all Appendices were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations.

Name: Thomas J. Roy, PE Title:

Signature: Date:

Connecticut P.E. Certification

“I certify that I have thoroughly and completely reviewed the Stormwater Pollution Prevention Plan prepared for this site. I further certify, based on such review and site visit by myself or my agent, and on my professional judgment, that the Stormwater Pollution Prevention Plan meets the criteria set forth in the General Permit for the Discharge of Stormwater Associated with Industrial Activity effective on October 1, 2011. I am aware that there are significant penalties for false statements in this certification, including the possibility of fine and imprisonment for knowingly making false statements.”

Name: David P. Brassard Title: Senior Project Manager, LEP, P.E.

Signature:

Date:

6/28/23

License #: 19366

Non-Stormwater Discharge Certification

“I certify that in my professional judgment, the stormwater discharge from the site consists only of stormwater, or of stormwater combined with wastewater authorized by an effective permit issued under section 22a-430 or section 22a-430b of the Connecticut General Statutes, including the provisions of this general permit, or of stormwater combined with any of the following discharges provided they do not contribute to a violation of water quality standards:

landscape irrigation or lawn watering;

uncontaminated groundwater discharges such as pumped groundwater, foundation drains, water from crawl space pumps and footing drains;

discharges of uncontaminated air conditioner or refrigeration condensate;

water sprayed for dust control or at a truck load wet-down station;

naturally occurring discharges such as rising groundwaters, uncontaminated groundwater infiltration (as defined at 40 CFR 35.2005(20)), springs and flows from riparian habitats and wetlands.

This certification is based on testing and/or evaluation of the stormwater discharge from the site. I further certify that all potential sources of non-stormwater at the site, a description of the results of any test and/or evaluation for the presence of non-stormwater discharges, the evaluation criteria or testing method used, the date of any testing and/or evaluation, and the on-site drainage points that were directly observed during the test have been described in detail in the Stormwater Pollution Prevention Plan prepared for the site. I further certify that no interior building floor drains exist unless such floor drain connection has been approved and permitted by the commissioner or otherwise authorized by a local authority for discharge as domestic sewage to sanitary sewer. I am aware that there may be significant penalties for false statements in this certification, including the possibility of fine and imprisonment for knowingly making false statements.”

Name: Kay Lehoux Title: Environmental Compliance Manager

Signature:

Date:

6/26/2023

APPENDIX B

INSPECTION LOGS AND FORMS

ROUTINE FACILITY INSPECTIONS

BMP/activity Implemented? Maintenance Required?

Corrective Action Needed and Notes

1 Are all slopes and disturbed areas not actively being worked properly stabilized?

Yes No Yes No

2 Are natural resource areas (e.g., streams, wetlands, mature trees, etc.) protected with barriers or similar BMPs?

3 Are perimeter controls and sediment barriers adequately installed and maintained?

4 Are discharge points and receiving waters free of any sediment deposits?

5 Are storm drain inlets properly protected?

6 Is trash/litter from work areas collected and placed in covered dumpsters?

7 Are vehicle and equipment fueling, cleaning, and maintenance areas free of spills, leaks, or any other deleterious material?

8 Are non-stormwater discharges (e.g., wash water, dewatering) properly controlled?

9 (Other)

SWPP Plan Public Works Complex 66 Town Forest Road, Simsbury, CT

Public Works Complex Simsbury, Connecticut

STORMWATER QUALITY

Quarterly Visual Inspection Log

Inspector Name: _______________ Date: ____________ Time:

Outfall Location/Description: OF-1: Concrete pipe to rip rap, adjacent to Town Forest Road

Start time of current storm event:

Visual inspection within first 30 minutes of stormwater discharge? Y N (circle one)

Storm event notes/observations:

Current storm: ______ inches Nature of Discharge: rain snowmelt icemelt (circle one)

Last qualifying storm event at least 72 hours prior to sampling? Y N (circle one)

Item/Condition in Stormwater to be Checked

Yes

No

Observation/ Deficiency

Corrective Action & Date

Is the stormwater free of color?

Is the stormwater free of odor?

Is the stormwater clear?

Is the stormwater substantially free of floating, suspended or settled solids?

Is the stormwater free of foam?

Is the stormwater free of an oil sheen?

Any additional visual stormwater quality observations?

Department of Public Works June 2023 Simsbury, Connecticut

Department of Public Works

COMPREHENSIVE SITE COMPLIANCE EVALUATION

Semi-Annual Visual Inspection Log

Inspector: Permittee Signature:

Date: Time:

Potential Pollutant Source

Good Housekeeping Minimize Exposure Spill Prevention Problems Identified

Corrective Action Taken & Date Accept. See Notes Accept. See Notes Accept. See Notes

Loading/Unloading

Vehicle/Equipment Maintenance

Vehicle Washing

Fuel Dispensing Area

ASTs

Waste Oil ASTs

Outside Storage Areas

Waste Storage Areas

Department of Public Works June 2023

Salt, Sand, Gravel, and Topsoil Storage

Roof Drains, Vents, and HVAC Units

Stormwater Drainage System

Spill Response Equipment adequacy: Absorbent Pads and Booms (Yes/No):

Fire Extinguishers (Yes/No):

Sediment, Erosion, & Dust Control adequacy (Yes/No):

APPENDIX C

TRAINING AND PLAN REVISION LOGS

SWPPP Amendment Log

Amend.

No.

Description of the Amendment Date of Amendment

Amendment Prepared by [Name(s) and Title]

This Training Log is to be used to document Stormwater Pollution Prevention training sessions. Training includes discussion of the good housekeeping, spill prevention and response, and material handling practices at the facility. Additionally, the SWPPP is reviewed.

Name of Instructor:

Date of Training:

Student Name Signature

June 2023

Town of Simsbury Stormwater Pollution Prevention Plan

TRAINING LOG

Simsbury , Connecticut

Town of

Simsbury

APPENDIX D

SPILL DOCUMENTATION AND NOTIFICATION FORM

CONNECTICUT RELEASE REPORTING REGULATIONS – REPORTABLE QUANTITIES

Rev. 7/21/2022

Is the release authorized by a permit/license OR does it meet one of the exceptionsa to reporting?

Is the release to secondary containment AND less than

100 lbs & 15 gal AND meet applicable criteriab?

Is the release: to water, from a USTc, PCB, PFAS, or risk*to environment, human health, public safety?

REPORT

NO REPORT

Is the release oil or petroleum?

Is the release 5 gallons or more?

Is the released quantity or substance unknown? OR Is it known to contain ≥30%

Appendix A materiald?

Has it been removed or mitigated within 2 hours?

Is the release 10 pounds or more (solids) or 1.5 gallons or more (liquid)?

Has it been removed or mitigated within 2 hours by trained personnel?

Footnotes aExceptions – Allowed (regardless of exceedance or violation) by:

1) State or federal law;

2) Judgement or order of the court;

3) Contained under a laboratory fume hood;

4) Minor sheen from roadway, parking lot, driveway normal vehicle use;

5) Food products (if it does not pose a risk to human health or the environment);

6) Domestic sewage less than 100 gallons;

bCriteria for releases to containment, must be cleaned within 2 hours AND must NOT be:

1) more than 100lbs or 15gal.; 2) involve a UST or PCB; 3) create an emergency cUnless it is limited to drips from nozzle during dispensing;

dUnless contained under a laboratory fume hood *risk includes actual or…