Attachment 4 - SOW Kinneytown Dam CT Driller.pdf

U.S. Department of Transportation Volpe National Transportation Systems Center

Supplemental Phase II Environmental Site Assessment at the Kinneytown Dam Seymour, CT

Drilling Activities

STATEMENT OF WORK

1.0 INTRODUCTION

Under an Interagency Agreement, the U.S. Department of Transportation John A. Volpe National Transportation Systems Center (Volpe Center) is providing support to the U.S. Environmental Protection Agency (EPA) Targeted Brownfields Assessments (TBA) program. As part of this effort, supplemental Phase II Environmental Site Assessment (ESA) activities will be conducted at the Kinneytown Dam in Seymour and Ansonia, CT, including drilling and sampling activities.

Upon the completion of these activities, the plan is for the dam to be demolished, and the river restored. The demolition of the dam is not a part of this scope. This contract is specifically for drilling activities.

2.0 BACKGROUND

A Phase I ESA was completed by Volpe in April 2023 and updated in December 2024 for property acquisition, for the property known as the Kinneytown Dam (Subject Property). The Dam and related buildings are planned for demolition and restoration.

A Phase II ESA was completed in September 2024 by Volpe to evaluate the presence or absence of hazardous materials and petroleum products in sediment within the Upper Impoundment and within Coe Pond, and to assess upstream and downstream background conditions. Onsite Phase II ESA activities occurred at the Subject Property between May 6 and June 19, 2024.

3.0 Site Description

The Subject Property is an approximately 171-acre area located between Seymour, CT and Ansonia, CT, in New Haven County, Connecticut. The Subject Property is comprised of three parcels:

• 677 South Main Street, Seymour CT, map-block-lot (MBL): 11-03-35-0, approximately 18 acres

• 769 Derby Avenue, Seymour, CT, MBL: 12-04-34-0, approximately 99 acres

• 0 Hotchkiss Terrace, Ansonia, CT, MBL: 036 0001 0003, approximately 54 acres.

New Haven County is situated in southwestern Connecticut. The Subject Property topography is variable but generally slopes from higher elevations in the north to lower elevations in the south.

The Naugatuck River flows north to south and runs from approximately 50 ft. above mean sea level at the main impoundment to approximately 15 ft. above mean sea level south of the main impoundment. The river flows south from Seymour, CT, to Ansonia, CT. The main dam structure is located at the following coordinates: 41.368619, -73.085845. The lower dam structure is located at: 41.353742, -73.085387.

The Kinneytown Dam is 28 feet high and 455 feet wide, with an estimated impoundment area of 72 acres at Unit 1. A second dam, the Canal Reservoir Dam, is 30 feet high and 60 feet wide, with an estimated impoundment area of 37 acres. The facility was designed to produce electricity via turbines in two powerhouses. The Seymour powerhouse (powerhouse 1) is adjacent to the larger upper dam. The Ansonia powerhouse (powerhouse 2) is located approximately one mile south. A canal and reservoir (known today as Coe Pond) delivered water from powerhouse 1 to powerhouse 2.

Figures showing the Site location, topography of the surrounding area, and the Site layout are attached to the Site Specific Quality Assurance Project Plan (SSQAPP) included as Attachment 1 of this SOW.

3.1 Proposed Development

The dam and related buildings are slated to be removed and the surrounding river restored.

4.0 TASKS TO BE PERFORMED

A supplemental Phase II ESA investigation will be performed at the site to fill in data gaps that were identified after the initial Phase II activities. The tasks in this effort requires the environmental drilling contractor to follow the applicable Volpe Standard Operating Procedures (SOPs, see Attachment 2). A schedule for these tasks is provided in Section 4.

The Contractor must be a Connecticut licensed driller and shall conduct all work in accordance with Federal, State and local requirements. Where inconsistencies exist, the Contractor shall follow the most stringent requirement.

4.1 Work Plan

The Contractor shall submit a draft Work Plan within 10 business days after attending a kickoff meeting with the Volpe Center representatives that addresses the project requirements below.

The Work Plan shall detail the technical approach and schedule for conducting all activities as required and described below. To assist with preparation of the Work Plan, the contractor shall thoroughly review any Government-furnished information provided to them.

In addition, the work plan shall also identify any required permits needed to perform the work and the contractor shall be responsible for obtaining those permits as required. Copies of the permits shall be attached to the work plan as an appendix.

Additional components of the Work Plan are the Site Safety and Health Plan (SSHP), which shall include personnel health and safety precautions to be followed. The work plan shall also include a Risk Management Plan that identifies major risks and hazards on each site and discusses ways to minimize these risks. Specific water safety precautions and related risks shall be identified.

An outline summarizing the required content of the work plan is shown below:

1.) Technical Approach

a. Methods and procedures, including equipment to be used and equipment decontamination procedures, for activities described below

2.) Site Safety Health Plan (SSHP) 3.) Risk Management Plan

a. Identification of major risks

b. Risk mitigation plan

4.) Appendix

a. Copies of any state or local permits required to perform activates described herein or other supplemental information The Contractor should expect a 5 business day Volpe Center review period between submission of the Draft Work Plan and receipt of Volpe Center comments. The Volpe Center and the Contractor shall meet to discuss any comments and changes, if necessary. The Contractor shall make the changes and submit a Final Work Plan within 5 business days of the receipt of comments.

4.2 Sediment Sampling

Sediment samples will be collected from a minimum of twenty (20) sample locations from within the Upper Impoundment, and four (4) additional sample locations upstream (north) of the impoundment area and four (4) sample locations downstream (south) of the Kinneytown Dam, near the southern extent of the Naugatuck River. Sample locations are shown in Figures 4, 5, and 6 and are subject to change with the approval of the Volpe Project Implementer, based on site conditions.

Sediment sampling will begin downstream and move upstream (northward). A drilling contractor will utilize mechanical equipment, such as a telehandler forklift or excavator, to lift and place a drilling platform with drilling equipment into the Housatonic River at O’Sullivan’s Island Recreation Park and Derby Greenway in Derby, CT. The equipment will be moved east and then north towards the southern outlet of the Naugatuck River for downstream background sampling.

Upon completion, the equipment will be remobilized to the Derby Avenue Pump Station for Upper Impoundment sampling in the Naugatuck River. Following Upper Impoundment sampling, equipment will again be remobilized north to the Naugatuck River Greenway Trail, just north of the Tingue Dam in Seymour, CT, for upstream background sampling. For all equipment launch locations, if the area needs to be prepared with vegetation removal or placement of equipment mats or pads to access the river, coordination will be made through the Volpe Center representative and the Contractor will be responsible for preparing the area.

Initial Phase II sediment recovery rates varied throughout the project area due to the presence of soft sandy materials. Throughout the Upper Impoundment, poor recovery was observed from near-surficial sediment materials (0 – 5 ft. below sediment surface (bss)). Large volumes of material were required for the broad suite of laboratory analyses and low recovery rates made collection of sufficient volumes of materials difficult, resulting in larger composited sample intervals. To address these data gaps in this proposed supplemental Phase II activity, a hybrid drilling approach will be utilized to improve sediment recovery rates.

A drilling contractor shall advance a minimum of 28 sediment cores in accordance with EPA Methods for Collection, Storage and Manipulation of Sediments for Chemical and Toxicological Analyses: Technical Manual (2001). Sediment cores shall be advanced to bedrock or refusal.

Surface water is anticipated to be less than 5 ft. deep within the Upper Impoundment and 5-10 ft.

deep at background locations. Sediment cores shall be located as shown in Figures 4 – 6, and advanced at four downstream locations, 20 locations in the Upper Impoundment, and four upstream locations. The 20 Upper Impoundment coring locations shall be distributed in three cross-sectional segments of five borings each, plus a total of five standalone borings.

The contractor shall utilize a hybrid drilling approach including vibracore and ponar samplers for shallow sediment/near surface soft materials for improved sample recoveries, and a split-spoon sampler and mechanical drill for deeper sandy silt/silty clay material layers. A split-spoon sampler was previously used for all sediment depths in Phase II. The hybrid drilling approach may be used for all physical, elutriate, and chemical analysis.

At each sample location, the operator will first deploy a vibracore sampler to collect surficial sediment materials 0-6 ft. bss. If vibracore samplers do not return sufficient sediment volume for characterization and sample collection, a ponar sampler shall be advanced to collect near-surficial sediment from 0-2 ft. bss. Following this, a split-spoon sediment core sampler will be advanced from 5-6 ft. bss down to bedrock and/or refusal. Anticipated depths of sediment cores will vary across the impoundment areas due to changes in river topography and sediment build-up. During initial Phase II activities, sediment thickness ranged from approximately 10-20 ft. bss along the southern extent of the Upper Impoundment, increasing to 10-35 ft. bss in the central parts of the Impoundment, and decreasing to 5-15 ft. bss along the northern extent of the Upper Impoundment.

If shallow refusal is encountered above bedrock due to the presence of debris or other materials, a new sampling location and sampling core shall be established in the near vicinity and confirmed by on-site personnel, within a 10-ft. radius of the original location.

At each sample location, cores will be deployed and collected so that each sampled interval is representative of various depths of the sediment column. For example, two to three sample intervals are anticipated at each sample location, depending on total depth: one surficial sediment interval and one to two sample intervals, each 2-4 ft. thick, from sandy silt/silty clay layers. Due to the volume of material required for proposed sampling methods and limited volume collected from prior sediment cores, repetitive borings at each location may be required to obtain the desired quantity of material from a given depth. Large-diameter cores (3-in. diameter) are recommended, confirmed with drilling operators, and documented in the SSQAPP, to minimize repeat cores. If multiple borings are required, samples will be collected from core layers of similar stratigraphy and depth to create homogenous composite samples.

Volpe personnel will be responsible for the collection of all sediment and surface water samples from each of the proposed coring locations.

4.3 Decontamination

Contractor drilling equipment shall be decontaminated by the contractor, in accordance with Volpe SOP-018 Field Sampling Equipment Decontamination. During drilling activities in all project locations, drilling equipment will be decontaminated between sediment coring locations with liquinox, or related cleaning products, and water.

4.4 Demobilization

Following completion of all drilling activities, equipment shall be appropriately removed from the site. Waste shall be handled in accordance with Volpe SOP-020 Management of Investigation Derived Waste, as necessary (see Attachment 2).

4.5 Site Close-out

The Contractor shall provide a closeout email, detailing the work completed at each site, the duration of drilling activities, and confirmation all equipment has been removed from the Subject Property.

4.6 Safety and Security

The Contractor is responsible for site security and safety and shall provide adequate protection against accidental trespassing and security for staged equipment, if applicable.

5.0 DELIVERABLES

The Contractor shall prepare the following required deliverables in the quantities described in Table 2 below:

Table 1 - Deliverable Schedule and Details

Deliverable Name Format # Copies Date Due/ Recipient Draft Work Plan Electronic; MSWord* 1 10 business days after kickoff meeting with Volpe; send to contracting officers representative (COR) and altPOC

Final Work Plan Electronic MSWord*;

Electronic .pdf

5 business days after receipt of govt comments; send electronic copies to COR and altPOC

Site Close-out Memo and other Documentation

Electronic (scanned copies are fine)

10 business days after site demobilization.

* Any attachments/figures/appendices are permitted to be submitted in .pdf format if they cannot be submitted in .doc format

6.0 SCHEDULE

The Contractor shall prepare a schedule for completing the above-described tasks in this SOW and shall include it with their technical proposal. The Government would like this work completed as soon as possible. The period of performance for this effort shall be from date of award to December 31, 2025 with the field work preferably being completed in August-September. Approximate work hours are from 8:00 a.m. to 4:30 p.m. Monday through Friday. THERE IS TO BE NO WORK on the weekends, Government holidays, or outside of set work hours unless approved and coordinated with the Volpe Center COR. In consideration of the EPA TBA project locations and contract period of performance, schedule delays or impacts stemming from inaccessible river locations due to depth of water, obstructions, and inclement or extreme weather will be evaluated as needed.

7.0 TRAVEL

Contractor travel will be required in execution of contract tasks. All travel costs shall be built in and included in the pricing of line items for which travel may be required and in total fixed price amount.

8.0 PROJECT COORDINATION AND SITE ACCESS

The Contractor shall coordinate all activities and access through the COR. Contact with facility personnel, EPA, and local government representatives shall be coordinated through the Volpe representative and COR.

9.0 CONTRACTING OFFICER’s REPRESENTATIVE (COR)

The COR for this effort shall be:

Michelle Heimgartner Environmental Engineer USDOT/Volpe Center/V326 220 Binney St.

Cambridge, MA 02142 Tel: (617) 494-2098 Cell: (617) 913-0370 Email: michelle.heimgartner@dot.gov

10.0 Government Furnished Information (GFI)

1. Site-Specific Quality Assurance Project Plan, Kinneytown Dam, Seymour, Connecticut

Supplemental Phase II – Environmental Site Assessment

2. Volpe selected SOPs mailto:michelle.heimgartner@dot.gov

Attachment 1 Site-Specific Quality Assurance Project Plan, Kinneytown Dam, Seymour, Connecticut, Supplemental Phase II – Environmental Site Assessment

Attachment 2 Volpe Selected SOPs