CONNECTICUT

ADDENDUM #1

October 21, 2025

ITB 8593 Environmental Waste Remediation of 777 South Main and 359 Mill Streets

Please Be Advised:

All proposals of the above captioned project are hereby notified that the Contract Documents for the above referenced project are amended as noted in this Addendum No. 1.

This Addendum shall be part of the Contract Documents for the above referenced project as provided in the Invitation to Bid.

The Contract Documents are hereby amended as follows:

1) Revised Bid Table-1 is attached. It replaces the original and includes a 20% increase in PCB waste tonnage for contingencies. Use these quantities for bidding.

2) Revised Table of Contents is attached, this replaces similar page in the original ITB.

3) Revised SIP/EPA Approval documents are attached, including EPA clarification email.

These replace similar pages in the original ITB.

4) Pre-bid sign-in sheet from 10/20/2025 is attached.

Please refer to the questions and answers below.

Question: Is a Class A/B Demolition License required?

Answer: No. Class A applies to structures >2.5 stories or >35 ft; Class B to ≤2.5 stories or ≤35

ft. All structures are at/near grade.

Question: Is asbestos abatement included?

Answer: No asbestos abatement is anticipated.

Question: What permits/qualifications are required to bid?

Answer: Bidders must be OSHA HAZWOPER trained; listed on BOTH the CTDEEP’s Lists of “Permitted Hazardous & Regulated Waste Transporters” and “Permitted Spill Cleanup Contractors”; and experienced in PCB remediation under TSCA.

OFFICE OF THE DIRECTOR OF PURCHASING

MAUREEN McCAULEY

ASSISTANT DIRECTOR OF PURCHASING

235 GRAND STREET • WATERBURY, CONNECTICUT 06702 • PHONE: (203) 574-6749 • FAX: (203) 597-3437

Question: Are boring logs and monitoring well construction logs available? How many wells to abandon?

Answer: Yes, logs are in the RAP in the ITB. Plan to abandon 11 wells. Work must be performed by a licensed well driller.

Question: EPA Approval for PCB waste is referenced but not in the Table of Contents.

Answer: Revised Table of Contents and SIP/EPA Approval documents are attached, including EPA clarification email. These replace similar pages in the original ITB.

Question: Is deep excavation near retaining walls expected?

Answer: Excavation plans are in “Attachment-K Drawings for Remediation.” Shallow (0-2’ and 0–4’ ft) excavation nearest Mad River wall; deeper excavation is offset from the wall as shown.

Deeper excavation near wall is not anticipated at this time.

NOTE: Each Proposal over $50,000.00 submitted shall be accompanied by a Proposal Security (a Certified Check or Bid Bond) in the amount of ten (10) percent of the Total Proposal Price.

Thank you.

Maureen McCauley

Assistant Director of Purchasing – City of Waterbury

CONTRACTOR BID ESTIMATE SUMMARY SHEET

Task No. Subtask Contractor Task Description Unit Unit Cost Est.

Quantity

Bid

Amount ($) Comments

1A Mobilization (Contractor's and Site Facilities, Temp Fencing Around Basement Area) LS 1 See Figure 6 re: extent of basement area requiring temporary fencing.

1B Test Pits for waste characterization LS 1 Assumes 2 days of site work with excavator.

1C Well abandonment of 11 monitoring wells LS 1 Assume 20 ft deep, 2 inch diameter overburden wells.

1D Contractor's as-built showing excavation limits and grades LS 1 Survey extents and elevations of excavations & replaced material, including any capping if necessary.

1E Demobilization LS 1

2A Install Construction Entrance Pad LS 1

2B Sedimentation and Erosion Controls LS 1

3A Areas 1-2 & 4-9: Excavation, Loading, Transport & Disposal to Non-Hazardous Waste Facility TON 900 Estimated for bid, actual quantities will vary

3B 3,000 Gallons Cap. Vac truck (and driver) for NAPL removal at Area 4 EACH 3 Assumes 3 trucks x 3,000g, No. 2 Fuel oil.

3C Profiling, Transport and Disposal of non-hazardous fuel oil / water NAPL GAL 9,000 Estimated for bid, actual quantities will vary

3D Area 3: PCB / TSCA Area, Excavation, Loading, Transport & Disposal of Waste to TSCA or HW Landfill TON 2,500 Estimated for bid, actual quantities will vary

3E Area 3: PCB / Non-TSCA Area, Excavation, Loading, Transport & Disposal of Waste to Permitted Landfill TON 2,400 Estimated for bid, actual quantities will vary

3F Decontamination Cost of Contractors Equipment at Conclusion of Work LS 1 Per Decon Section of PCB Plan

NOTES:

LS LUMP SUMP GAL GALLON

na not applicable SQ FT SQUARE FEET

TABLE 1

ITB #8593

TASK 3 - Environmental Remediation: The work under this item shall include remediation in accordance with Section

02 6000 and attachments in the Contract Documents and applicable regulations, including health and safety, plan preparation, certifications, wastewater discharge permitting, temporary controls, temporary stockpiling facilities, monitoring, sampling, coordination, excavation, handling, transportation, and off-site disposal, in accordance with the Contract Drawings and Technical

Specifications.

Note: The Estimated Quantity shown to the right is included for cost comparison purposes and will be included in the Agreement between the selected Contractor and the City of Waterbury. This line item will be paid on a per ton basis with any unused portion credited back to the City of Waterbury at the agreed upon per ton cost included on this form at the end of the job.

TASK 2 - Sedimentation and Erosion Controls: The work under this item shall include all materials, equipment and labor for the installation and maintenance of a construction entrance pad and sedimentation and erosion controls, including but not limited to construction entrance, sediment filter fence, hay bales, and inlet protection required either by the plans, or City staff or assigned representative, in accordance with the Contract

Drawings and Technical Specifications. TASK 2 TOTAL

TASK 1 -Site Preparation: The work under this item shall include all personnel and equipment necessary for mobilization and demobilization, and administrative costs including bonding, schedule, the movement of all the contractor's storage facilities, safety fencing, site security features, maintenance and protection of traffic, transport of equipment to and from the project site, construction staking, as shown on the drawings and/or as otherwise necessary to the performance of the work as shown and in accordance with the Contract Drawings and Technical

Specifications. Assume 1 day of test pits are needed prior to the start of work to collect waste characterization samples. TASK 1 TOTAL

TASK 3 TOTAL

Task No. Subtask Contractor Task Description Unit Unit Cost Est.

Quantity Bid Amount ($) Comments

4A Import of process stone, or washed stone (as applicable, quantities estimated).

Compaction of stone in 1 foot lifts, per geotechnical requirements. Testing of compaction by Owner.

TON 6,400 Estimated for bid, actual quantities will vary

4B Rough pour concrete slab 6-inches thick, 4 feet below grade for PCB cap SQ FT 2,000 Estimated for bid, if needed

4C Import topsoil in disturbed areas beyond proposed building and parking area CY 200 Estimated for bid, actual quantities will vary. See Sheet C2.0 Site Stabilization Plan

5A Placement/spreading of topsoil to stabilize area (assume 3-inches of topsoil) and seeding of the area beyond the limits of the planned building. SQ FT 20,000 Estimated for bid, actual quantities will vary

6A Submittal of Contractor's Health and Safety Plan (HASP) LS 1

6B General Conditions, Bonding, Permitting, Scheduling and All Adm Costs LS 1

6C Contractor's Exploratory Excavations (as applicable) LS 1 If any additional exploratory excavations are required to complete the project. Contractor to provide examples.

6D Project Closeout Documentation (Manifests, As-Built Survey, Logs) LS 1

NOTES: LS LUMP SUMP CY CUBIC YARD

na not applicable SQ FT SQUARE FEET

TASK 6 TOTAL

TASK 6 - General Conditions: Perform all incidental work items required to complete the work as shown on the

Drawings and as called for in the Specifications. Includes all work not otherwise specified but obviously necessary for the proper completion of the work, including, but not necessarily limited to, permitting, meetings, submittals, mock-ups, exploratory excavations, construction layout, measurements, general project coordination, health and safety, and project documentation.

TASK 7 - Project Closeout Documentation: Provide all project waste manifests and bills of lading, waste facility scale tickets, documentation of clean imported materials, as-built survey detailing limits of TSCA and non-TSCA work areas and any concrete caps.

TABLE 1 (continued)

ITB #8593

CONTRACTOR BID ESTIMATE SUMMARY SHEET

Note: The Estimated Quantity shown to the right is included for cost comparison purposes and will be included in the Agreement between the selected Contractor and the City of Waterbury. This line item will be paid on a per ton basis with any unused portion credited back to the City of Waterbury at the agreed upon per ton cost included on this form at the end of the job.

TASK 7 TOTAL

TOTAL CONTRACTOR BID ($)

TASK 4 - Earthwork, Grading and PCB Cap Allowance: The work under this item shall include all materials, equipment, and labor to perform necessary import, placement, compaction and grading operations as shown on the

Contract Drawings and described in the Technical

Specifications. Work under this item shall include all rough and fine grading brought to the subgrade elevation required prior to the application of stone base material, processed stone or topsoil as shown in the contract documents. Allowance added if PCBs require EPA cap to conform to high-occupancy areas, which will require the pouring of a concrete cap 4 feet below grade to a minimum thickness of 6-inches. Rebar should be placed at the corners of capped areas and grade stakes should be installed prior to pours to assure cap meets minimum 6-inches minimum thickness. Import and spread topsoil to areas outside building footprint.

TASK 5 TOTAL

TASK 5 - Site Stabilization: The work under this item shall include all materials, equipment, and labor to install areas of conservation mix seeding, placement of topsoil, seeding and establishment for disturbed areas from remediation, or contractor equipment. This work is shown on the Contract

Drawings and described in the Technical Specifications.

TASK 4 TOTAL

INVITATION TO BID 8593 TOC-3 Table of Contents

01 3300 Submittal Procedures 6 01 5713 Temporary Erosion and Sedimentation Controls 11 01 5714 Temporary Dust Control 3 01 5725 Flood Contingency Plan 11 01 7113 Mobilization 7 01 7124 As-Built Survey 2 01 7700 Project Close-Out 3 01 7839 Record Documents 5

Division 2 – Existing Conditions 02 4123 Site Demolition 5 02 6000 Contaminated Site Material Removal 7

Division 31 – Earthwork 31 1000 Site Clearing 4 31 2310 Earthwork 21

Division 32 – Exterior Improvements 32 3113 Chain Link Fences and Gates 13 32 9220 Conservation Mix Seeding 10

Self-Implementing PCB Clean Up Plan & EPA Approval 364

Attachment K –Drawings for Remediation 12

Attachment L – Prevailing Wage Rates

Attachment M – EPA Guidelines 27 Davis Bacon Requirements 12

Attachment N – DECD Guidelines 34

WSP USA

6 Research Drive, Suite 260 Shelton, CT 06484

Phone: +1 (203) 929-8555 Fax: +1 (203) 926-9140 wsp.com

TECHNICAL MEMORANDUM

TO: Katherine Woodward, PE, PhD PCB Coordinator, EPA Region-1

FROM: Matthew P. Kennedy, LEP Lead Environmental Geologist, WSP USA

RE: Request for Approval & Response to EPA Comments Self-Implementing PCB Clean-up Plan, WSP, November 13, 2024 777 South Main Street, Waterbury, Connecticut

DATE: July 10, 2025

INTRODUCTION

WSP has prepared this Technical Memorandum to provide a response to informal comments received on the Self-Implementing PCB Clean-up Plan (SIP), dated November 13, 2024, which was provided to EPA on November 14, 2024. Please note that the City of Waterbury and its development agency, Waterbury Development Corporation, currently wish to proceed with the clean-up and disposal of polychlorinated biphenyls (PCBs) on the Site in accordance with the SIP per 40 CFR 761.61(a).

Requests for Approval

On behalf of the City of Waterbury, WSP respectfully requests EPA approval of the November 13, 2024 SIP Notification. WSP requests that, where applicable, such approval include additional conditions/contingencies discussed in our conference call with your group and CTDEEP remediation division on July 10, 2025.

Notably, the following additional requests were discussed for inclusion in EPA’s approval:

• The option of having contractors segregate and dispose of soils removed from certain areas of the Site with as-found PCB concentrations less than 50 parts per million (ppm) to alternate disposal facilities permitted to accept such wastes.

As discussed in our July 10, 2025 call, if this option is exercised, all soils from areas with as-found PCB concentrations greater than 50 ppm would be removed first and those locations verified through sampling. Following successful verification that all greater than 50 ppm soils have been removed from those areas, soils with as-found PCB concentrations less than 50 ppm from outside those areas will be removed and characterized for disposal at the alternate disposal facilities permitted to accept such wastes.

Recent and historical data indicates that soils with as-found PCB concentrations greater than 50 ppm were identified at the Site within PCB Work Area A as depicted on Figure 2 in the November 2024 SIP. A copy of this figure is attached (Attachment A) for reference. Recent and historical data did not indicate the presence of soils with as-found concentrations of PCBs greater than 50 ppm outside of PCB Work Area A.

• The option of making a field decision to cap any soils with PCB concentrations greater than 1 ppm but less than 10 ppm with a concrete cap meeting the requirements of 40 CFR 761.61(a)(7). The November 2024 SIP calls for removal of soils with PCB concentrations greater than 1 ppm but indicates that, due to the heterogeneity of fill material and site constraints, it may become necessary or otherwise desirable to cap such soils meeting this criteria. At this time, it is anticipated that such caps, if necessary, will consist of a minimum thickness of 6 inches of concrete and that such caps may be further covered in clean soil to meet the Connecticut Remediation Standard Regulations (RSRs) requirements for the “inaccessible soil”1 conditional exemption which is necessary in most circumstances in Connecticut for soils with PCB concentrations greater than 1 ppm to remain on-site and to be in compliance with the “industrial/commercial direct exposure criteria”2. Any soils capped in this manner would be staked/pinned to ensure adequate thickness of the concrete pour and to permit an accurate survey documenting the location, extent, thickness, and elevation of such cap and the capped soils. The locations will be surveyed by a licensed surveyor. Any soils capped with concrete and/or soil that will be considered “inaccessible soil” per the RSRs would be included in an ELUR recorded on the property deed to ensure that the soils protecting the cap are not disturbed.

Response to Comments

WSP received a list of informal comments attached to an email from EPA dated June 24, 2025. Based on our discussion, WSP has summarized EPA’s requests and provides responses as follows:

EPA’s General Comments on the SIP Notification:

1) EPA requested the contact information for Ronald Cassella who signed the certification in the November SIP notification.

WSP Response: Ronald Cassella, VP of Operations and Construction at Waterbury Development

Corporation (WDC). 203-346-2607, Ext. 7277

2) EPA requested information on where to find the laboratory data and boring logs to support the data summarized in the SIP tables and figures.

WSP Response: Much of this laboratory data was obtained directly from EPA and was contained in a previous Targeted Brownfields Assessment (TBA) performed by Nobis Engineering for EPA in

2017/2018. Laboratory and field data from WSP’s 2024 remedial design investigation is included in the Remedial Action Plan (RAP, finalized January 2025). A copy of the RAP can be obtained from

CTDEEP:

https://filings.deep.ct.gov/DEEPDocumentSearchPortal/Home/DisplayPDF?DocID={F019D194-

0000-CB11-8683-DFB37BC620F6}

3) EPA requested clarification on the intended high occupancy use of the property and potentially utilizing a cap for PCBs less than 10 ppm.

1 The State of Connecticut regulatory reference for the definition of “inaccessible soils” is included in the Regulations of Connecticut State Agencies (RCSA) Section 22a-133k(1)(a)(39).

2 The State of Connecticut regulatory reference for use of the “inaccessible soil” conditional exemption for PCBs is included in RCSA Section 22a-133k(2)(b)(4). Please note that use of this exemption requires an Environmental Land Use Restriction (ELUR) prohibiting exposure to these soils, prohibiting residential activity, and requiring that any soil used to render the soils “inaccessible” be maintained to ensure no alteration of the elevation of the ground surface, and to require than any bituminous or reinforced concrete or building used to render the soils inaccessible be maintained in good condition and free of gaps or cracks that could expose such soils.

https://filings.deep.ct.gov/DEEPDocumentSearchPortal/Home/DisplayPDF?DocID=%7bF019D194-0000-CB11-8683-DFB37BC620F6%7d https://filings.deep.ct.gov/DEEPDocumentSearchPortal/Home/DisplayPDF?DocID=%7bF019D194-0000-CB11-8683-DFB37BC620F6%7d

WSP Response: These details, including the potential use of a cap, the general construction specifications, and the anticipated measures to ensure that the cap continues to function to render underlying soils with PCBs more than 1 part per million (ppm) but less than 10 ppm “inaccessible”, are described in the request for approval above.

Additional note: Current plans call for the southern portion of the Site to include a covered permanent structure with a concrete slab floor to be used as a seasonal farmer’s market. This structure would be surrounded by paved parking areas and landscaping. If one or more caps are ultimately utilized, the location, thickness, elevation, and construction of the cap(s) would be documented and institutional controls recorded to ensure the integrity of any materials rendering soils “inaccessible”. Such controls would also include a schedule for the inspection of such cover materials as required by Connecticut regulation.

4) EPA requested additional information of how concrete chip samples were collected during site characterization.

WSP Response: The concrete core samples were collected from the top 0.5 to 2 cm of the concrete slab using hand tools including a chisel and a drill to characterize the top portion of the slab surface closest to the likely source of contamination, if any.

5) EPA requested additional information on the site CSM and site characterization scope regarding defining the horizontal extent of the identified PCB impacts. Specifically, the comments reference the prior CSM supposition that surface spills may have been tracked from one identified PCB work area to another.

WSP Response: Industrial activities which resulted in the PCB impacts ceased prior to 1978.

Documentation describing releases of possible PCB-containing substances has not been identified.

As such, the source and mechanism of the releases are actually unknown. PCBs have been identified in material that can be best described as urban fill and therefore the nature of contaminant migration within this material is also unknown. Specifics regarding known or suspected historical uses of various portions of the Site and the rationale for soil boring locations are included in the in the SIP and RAP.

EPA’s Specific Comments

• EPA provided clarification in the definition of “PCB remediation waste” regarding the fact that the PCB remediation waste definition is tied to the concentration of the source and therefore remediation of such wastes at any as-found concentration may be regulated by TSCA if the source contained PCBs at a concentration of greater than 50 ppm.

WSP Response: WSP acknowledges the distinction provided by EPA and the definition of PCB

Remediation Waste 40 CFR 761.3. WSP also maintains the following: 1) PCB impacts identified at the Site were likely from disposal during industrial operations prior to April 18, 1978, 2) some of the

PCB impacts are currently found at concentrations greater than 50 ppm, and 3) the concentration of the original spill(s) which resulted in the identified PCB impacts is unknown.

• EPA noted the reference in the SIP regarding soils potentially requiring a cap.

WSP Response: This subject was discussed in our conference call and additional discussion is provided in the request for approval portion of this technical memorandum.

• EPA provided additional comments on the pre-1978 determination, the prior CSM supposition regarding the delineation of PCBs potentially tracked from one area to another, and the body of site characterization data used to support the CSM provided in the November 2024 SIP.

WSP Response: At this time, WSP acknowledges that the source and method of distribution of PCBs within the proposed remediation areas are actually unknown. Based on this fact, the plans for clean-up and disposal of the PCBs at the Site under 40 CFR 761.61(a) including strict adherence to Subpart

O verification sampling. Additional site characterization regarding potential sources and possible release dates is not planned at this time.

• EPA provided additional comments regarding the prior CSM supposition of potential tracking of PCBs from one location to another. The comments suggest that the SIP indicates that PCBs were tracked from Area B into Area A. The comments also reference the spacing of general site characterization samples collected on the northern portion of the Site (WSP-1 through WSP-7).

WSP Response:

o WSP reviewed the SIP language (Section 4.1) and offers clarification that the sentence was actually referring to the earlier CSM consideration that impacts in PCB Work Area B may have resulted from the tracking of impacts from PCB Work Area A into PCB Work Area B.

EPA had similar comment regarding PCB Work Area C. At this time, WSP acknowledges that the source and method of distribution of PCBs within the proposed remediation areas are actually unknown. No additional site characterization regarding potential sources and possible release dates is planned at this time.

o With regard to the northern portion of the Site, the working CSM utilized by WSP (and by prior EPA contractors) is that this portion of the property was physically isolated from, and not associated with, the industrial operations on the southern portion of the Site (area of Site with identified PCBs). The northern Site areas historically were occupied by a large mill pond to the north of the industrial facility at 777 South Main Street which provided water via underground head race to an entirely separate mill located to the west of the Site. The former mill pond was later used as a parking area when the land was presumably drained and filled.

The CSM determination is that operations that may have involved the use, handling, and release of substances containing PCBs were not conducted on this portion of the Site.

Furthermore, the assessment of the fill material on this portion of the Site and the associated adjoining property to the north (359 Mill Street) did not identify PCBs at any concentration.

The clean-up of the northern portion of the Site is not part of the SIP or the associated notification for which approval is requested.

• EPA requested an explanation for the presence of PCBs in deeper samples, specifically PCB Work Area D.

WSP Response: WSP notes that PCBs were historically identified by prior EPA contractors in multiple deeper samples (generally 4 to 10 feet bgs) at seemingly random locations within the PCB remediation areas at the Site. The presence of PCBs in both surface samples and much deeper samples, and the absence of PCBs in soil strata in between, suggested that the release mechanism of impacts to the deeper soils was not well understood.

Supplemental site characterization work performed by WSP investigated whether there was evidence of a potential other source of PCBs at depth (such as a release of potential PCB-containing waste oil or waste water at depth), or whether the PCBs identified at depth may have been a result of sloughing of surface soils down the open sample hole or a result of other cross contamination during prior subsurface investigations. WSP completed soil borings immediately adjacent to various locations on site with elevated PCBs identified at depth. WSP utilized multiple field and drilling techniques to minimize sloughing of surface soils down the borehole.

In each location, WSP generally obtained soil samples that either did not contain PCBs or contained

PCBs at significantly reduced concentrations. In most locations, the findings strongly suggested that the previously identified PCB concentrations at depth were the result of drilling in loose unconsolidated fill material which could be expected to slough surface soils down the open borehole.

No other lines of evidence suggesting separate releases at depth were indicated in WSP’s data.

However, due to the existence of data suggesting the presence of PCB impacts in these strata, and the fact that their presence could not be entirely ruled out during recent supplemental site characterization, the remediation at these depths (i.e., excavation) was included in the work plan for this project.

• EPA requested additional figures showing the investigation points relative to the identified PCB Work Areas.

WSP Response: WSP directs EPA to the current figures included in the November 2024 SIP and the

January 2025 RAP. Data has historically been depicted on most figures during site characterization without labels for individual sample identification and concentration due to the difficulty in depicting over 450 data points within such a relatively small area. GIS figures with heat maps and/or sample symbols color coded by concentration and/or depth have generally been deemed most helpful. Please note that all sample locations are accurately identified on the plan sheet (Figure 4) attached to the

January 2025 RAP.

• EPA requested information on the potential removal of asphalt and concrete from the Site during PCB remediation activities.

WSP Response: WSP notes that the removal of PCB-impacted asphalt and concrete surfaces/structures (other than fragments of these items already present in the fill material) is not a significant element of the SIP, though it is mentioned in the SIP generally as a contingency for contractors bidding on the project. If significant asphalt or concrete surfaces/structures requiring bulk removal are identified during within the PCB Work Areas during remediation, the materials will be properly characterized for PCBs and disposed of accordingly at disposal facilities permitted to accept such wastes.

• EPA requested clarification on whether any segregation of wastes with PCBs greater than 50 ppm and less than 50 ppm is planned.

WSP Response: Per the request for approval in this technical memorandum, the City would like to retain the option of segregating wastes for potential alternative disposal options if there turns out to be a significant cost benefit in doing so. While the means and methods will be a matter to be discussed between the City and their contractor, WSP proposes that the cut lines between the “greater than 50 ppm” and “less than 50 ppm” soils be the perimeter of PCB Work Area A. WSP reviewed the recent and historical data and confirmed that there has not been detections of PCBs at a concentration greater than 50 ppm beyond the limits of PCB Work Area A. If an alternative disposal option is to be approved, per our conversation on July 10, 2025, remedial work within PCB Work Area A would be completed prior to commencing any work outside of PCB Work Area A.

• EPA requested additional information on whether dewatering is planned as a reference to dewatering equipment noted in a conceptual project layout sketch in the SIP.

WSP Response: Dewatering is not anticipated as part of this project at this time. In the event that significant rainfall was to necessitate the handling of liquid wastes during this project, such wastes will be containerized and characterized for disposal in accordance with applicable regulations.

• EPA requested information regarding sampling intervals utilized during site characterization.

WSP Response: WSP has reviewed analytical data and available boring logs for over 450 soil samples collected and analyzed for PCBs by prior EPA contractors and WSP. The data has consisted of sampling of various depth intervals including sample intervals as small as 1-2 inches. Based on the presence of PCBs in fill material and the density of sampling (horizontal & vertical), WSP believes that sufficient data has been collected via appropriate protocol to properly characterize the

Site, and that the site clean-up work plan detailed in the November 2024 SIP and clarified in this technical memorandum (including verification by Subpart O procedures utilizing a 1.5-meter sampling grid) will be sufficient to properly document site closure.

• EPA identified and questioned a reference to an OSHA TWA for a PCBs action level in the dust monitoring plan included in the SIP.

WSP Response: The dust monitoring plan does discuss the OSHA standard but ultimately concludes with a recommended dust standard based on the National Ambient Air Quality Standard (NAAQS) for dust (PM10) which is 0.150 mg/m3. On this project, work zone and perimeter dust monitoring will be conducted at the start of work and hourly during intrusive activities using a real-time particulate monitor (e.g., MIE PDR-1000, or similar). Monitoring will occur at upwind and downwind perimeter areas, with results recorded hourly in four cardinal directions. Results will be compared to the following actions levels:

o Action Level 1: If downwind PM-10 levels exceed background by 100 µg/m³ over 5 minutes, implement dust suppression. Work may continue if no visible dust observed.

o Action Level 2: If levels exceed 150 µg/m³ above background after suppression, stop work and reassess. Resume only when levels drop below this threshold and no visible dust is observed.

Visual assessments for fugitive dust will be ongoing. The Site Safety Officer (SSO) may adjust action levels or require personal air sampling if needed for exposure assessment.

Attachments

Attachment-A: Figure - PCB Work Areas, Self-Implementing PCB Clean-up Plan, Prepared by WSP, dated November 13, 2024

Waterbury Development Corporation

777 SOUTH MAIN STREET

WATERBURY, CONNECTICUT

PREPARED FOR PCB WORK AREAS

NOVEMBER, 2024

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CERTAIN INFORMATION.

NOTICE: THIS DRAWING HAS BEEN PREPARED UNDER THE

DIRECTION OF A PROFESSIONAL. DO NOT ALTER THIS

DOCUMENT IN ANY WAY WITHOUT THE WRITTEN CONSENT

OF WSP USA INC.

0 50 100

SCALE IN FEET

± FIGURE 2

Drawn: 11/13/2024 Service Layer Credits:

WSP USA Inc.

6 RESEARCH DRIVE

SUITE 260

SHELTON, CT 06484

TEL: (203) 929-8555

LEGEND

Property Boundary

PCB Work Areas

SELF-IMPLEMENTING

PCB CLEANUP PLAN

777 SOUTH MAIN STREET

WATERBURY, CONNECTICUT

REM IDs: 9451,13393, 23266

UNITED STATES ENVIRONMENTAL PROTECTION

AGENCY, REGION-1

BSG GROUP - CONNECTICUT INC.

655 WINDING BROOK DRIVE, GLASTONBURY, CT

WATERBURY DEVELOPMENT CORPORATION

83 BANK STREET, WATERBURY, CT

PROJECT NO.: 31401617.004

DATE: NOVEMBER 13, 2024

WSP USA

6 RESEARCH DRIVE, SUITE 260

SHELTON, CT 06484

PHONE: +1 203-929-8555

FAX: +1 203-926-9140

WSP.COM

Self-Implementing Clean-up Plan Project No.: 31401617.004 777 South Main Street, Waterbury, CT

WSP

November 2024

Page i

S I G N A T U R E S

PREPARED BY:

Matthew P. Kennedy, LEP Geologist, Lead Consultant

REVIEWED BY:

William K. Flick CPG, LEP Vice President

This report was prepared by WSP USA for the account of BSC Group-Connecticut, Inc., in accordance with the professional services agreement. The disclosure of any information contained in this report is the sole responsibility of the intended recipient. The material in it reflects WSP’s best judgement in light of the information available to it at the time of preparation. Any use which a third party makes of this report, or any reliance on or decisions to be made based on it, are the responsibility of such third parties. WSP accepts no responsibility for damages, if any, suffered by any third party as a result of decisions made or actions based on this report. This limitations statement is considered part of this report.

777 South Main Street, Waterbury, CT

WSP

November 2024

Page ii

TABLE OF

CONTENTS

1 INTRODUCTION

1.1 OBJECTIVE & SUMMARY

1.2 Notification and Certification Requirements

2 SITE DESCRIPTION AND PHYSICAL SETTING

2.1 Site Use History

2.2 Location and environmental setting

2.3 Geology

2.4 Site Soil

2.5 Hydrogeology

2.6 Surrounding Land Use

3 PREVIOUS INVESTIGATIONS

3.1 Initial Site Assessments

3.2 Initial Site Characterization

3.3 Source of Release

3.4 Remedial Investigation

3.5 Nature and Extent of Contamination

4 REMEDIATION PLAN

4.1 Self-Implementing Clean-Up Plan (SICP)

4.1.1 Access Control

4.1.2 Utility Clearance

4.1.3 Erosion Control

4.1.4 Excavation & Off-site Disposal

4.1.5 Post-Excavation Sampling

4.1.6 Backfill and CAPPING

4.1.7 Clean Backfill

4.1.8 Dewatering

4.1.9 Transport and Disposal

4.1.10 Equipment and personnel Decontamination

5 HEALTH AND SAFETY

6 CERTIFICATION

777 South Main Street, Waterbury, CT

WSP

November 2024

Page iii

FIGURES

Site Locus Historical Use Plan Plate - Sampling Locations Plan Figures – Site Layout, PCB Concentrations, & Remediation Areas

TABLES

Table 1 – Summary of PCB Concentrations in Soil (LBG, 2015-2016) Table 2 - Summary of PCB Concentrations in Soil (NOBIS, 2017-2018) Table 3 - Summary of PCB Concentrations in Soil (WSP, 2024)

APPENDICES

Appendix A – Dust Monitoring Plan Appendix B – PCB Due Diligence Review, WSP, March 2024

777 South Main Street, Waterbury, CT

WSP

November 2024

1 INTRODUCTION

WSP USA Inc. (WSP) has prepared this Self-Implementing Cleanup Plan (SICP) for the property located at 777 South Main Street, Waterbury, Connecticut (the “Site”) on behalf of the BSC Group- Connecticut, Inc. (BSC), the planning consultant for City of Waterbury, Connecticut and its economic development agency, Waterbury Development Corporation (WDC). (Site Locus, Attached).

The SICP describes an approach and work plan for the remediation of soils impacted with polychlorinated biphenyls (PCBs) in accordance with United States Environmental Protection Agency (EPA) requirements for notification of a SICP per Title 40 of the Code of Federal Regulations (CFR) §761.61(a)(3), Self-implementing On-Site Cleanup and Disposal of PCB Remediation Waste.

1.1 OBJECTIVE & SUMMARY

The objective of this SICP is to notify and gain approval from the EPA of a work plan for the remediation of PCB-contaminated soil related to historical industrial activities at the Site.

The Site has been characterized through assessment of soil, concrete, sediment, and groundwater to determine the presence or absence and extent and degree of PCB contamination and provide data necessary to design remedial plans for the Site. Site characterization activities have been completed in accordance with EPA-approved Site Specific Quality Assurance Project Plan (QAPP) (Site-Specific Quality Assurance Project Plan, Addendum A-6, dated May 2024) outlining procedures to ensure that sufficient quantity and quality of sampling data was collected to inform decisions regarding the identification and remediation of PCBs in site media. In addition, since the Site is enrolled in the State of Connecticut Brownfield Remediation and Revitalization Liability Relief Program (BRRP), collected data has been evaluated using strict quality assurance and quality control (QA/QC) standards including the Connecticut Department of Energy and Environmental Protection (DEEP) Reasonable Confidence Protocols (RCPs) for laboratory data.

Site characterization has included multiple phases of investigation and assessment through collection and analysis of 485 soil samples across the Site from multiple depth intervals. These investigations (2015 to 2024) have identified the presence of PCBs at concentrations up to 2,200 parts per million (ppm) in shallow soil on the southwestern portion of the Site. Review of historical documentation has determined that the release(s) of PCBs most likely occurred during heavy industrial operations conducted at the Site between the 1930s and late 1960s (Due Diligence Review, 777 South Main Street, Waterbury, CT, by WSP, dated March 29, 2024 (Appendix B).

At select sample locations, PCBs have been identified at the Site exceeding the DEEP Residential Direct Exposure Criteria (RDEC) of 1 milligram per kilogram (“mg/kg”, also referenced as parts per million or “ppm” in this report) and Industrial/Commercial Direct Exposure Criteria (I/C DEC) of 10 mg/kg as published in the Remediation Standard Regulations (Regulations of Connecticut State Agencies “RCSA” §22a-133k-1 through 22a-133k-3). Select sample locations also had identified PCBs at concentrations exceeding the 50 ppm threshold for a defined “PCB remediation waste” subject to the federal Toxic Substances Control Act (TSCA). In general, the highest concentrations of PCBs have been detected in shallow soils (i.e., from grade to approximately 2 feet below grade (ft bg)). PCBs have not been detected above the laboratory reporting limit in any of the groundwater samples collected at the Site (Groundwater Sampling Results, WSP, September and December 2023). Other identified site contaminants include metals and petroleum compounds. The planned redevelopment is anticipated to be

777 South Main Street, Waterbury, CT

WSP

November 2024 integrated with site remediation activities and will include excavation of PCB-impacted soil. As this SICP focuses on impacts of PCBs regulated by TSCA, separate compliance actions associated with DEEP regulations for other constituents of concern are not discussed in detail. A remedial action plan (RAP) will be submitted to the DEEP under separate cover to address other constituents of concern.

This SICP proposes Site cleanup levels to meet the requirements of 40 CFR 761.61(a)(4)(i)(A) “high occupancy areas” and will remediate soils impacted with PCBs to concentrations of ≤ 1 ppm by excavation and off-site disposal. The SICP also includes a provision for capping certain areas with PCBs in soils that are > 1 ppm but ≤ 10 ppm through the use of constructed caps consisting of the uniform placement of concrete, asphalt, or similar materials to prevent human exposure, infiltration of water, and erosion of the underlying soils meeting the requirements of 40 CFR 761.61(a)(7) “Cap Requirements” and the applicable sections of 40 CFR 761.61(a)(8) “Deed restrictions for caps, fences and low occupancy areas” pertaining to cap maintenance.

1.2 NOTIFICATION AND CERTIFICATION REQUIREMENTS

Pursuant to communications with the EPA Region 1 PCB Coordinator, WSP has developed this proposed SICP for the clean-up of PCBs at the Site. Per the requirements of per 40 CFR §761.61(a)(3)(i), this SCIP describes the nature and extent of the PCB-impacted materials at the Site, provides a summary of location and distribution of PCB impacts using tables and maps, provides a clean-up plan and proposed schedule for the remediation activities, and provides the required notification at least 30 days prior to commencing Site clean-up under the self-implementing cleanup option for on-Site cleanup and disposal of PCB remediation waste.

This notification also serves as written certification by the owner of the Site that all documentation of the sampling plans, sample collection procedures, and laboratory extractions and analyses used to assess and characterize the PCB impacts are on file and available for EPA inspection as required per 40 CFR §761.61(a)(3)(i)(E). The Site is owned by the City of Waterbury and a certification by a representative of its economic development agency (Waterbury Development Corporation, 83 Bank Street, Waterbury, CT) is included in Section 6.

777 South Main Street, Waterbury, CT

WSP

November 2024

2 SITE DESCRIPTION AND PHYSICAL SETTING

2.1 SITE USE HISTORY

The Site was first developed for industrial purposes in the mid-1870s and was historically occupied by various manufacturers of metal items, including brass buttons and other brass goods. Historic operations utilized the storage of fuel in a 15,000-gallon underground storage tank (UST) that was reportedly abandoned in place on the Site, and included processes involving burnishing, soldering, annealing, painting, and plating. (Historical Site Use Plan, Attached).

From the 1875-1950, industrial/manufacturing activities at the Site included the manufacture of brass products by companies including the Steele & Johnson Manufacturing Company (1875-1920s) and the Waterbury Button Company (1930s-1950). Subsequent identified Site ownership/occupancy included the following: American Chemical & Refining Company, Waterbury Button Company Shipping Department, and Steele & Johnson Manufacturing Company (1961-1967); Waterbury Companies Inc.

Receiving Department & Waterbury Button Co. Shipping Department (1973); vacant from 1974 and 1976; and Fleisher Finishing-Warehouse (1978). From 1979 to 1985, the Site address and/or occupant are not listed in historical documents. Subsequent property owners/occupants included Fleisher Finishing (1986); Philip J. O’Brien (1986-1998); and Southend Neighborhood Revitalization Corporation (1998).

From 1998 to 2007, various demolition and abatement activities are listed for the Site in City of Waterbury records. No records of spills of hazardous substances or petroleum products, or handling of equipment or substances containing PCBs were uncovered. The Site currently consists of cleared undeveloped land except for remnants of foundation walls and floor slabs associated with the former building complex.

2.2 LOCATION AND ENVIRONMENTAL SETTING

The irregular-shaped, 1.96-acre, City-owned property (M/B/L 0369-0294-0020) is located south of the intersection of South Main Street and Mill Street, and to the northwest of the Mad River. The Site, which was previously developed with a historical industrial facility, is currently vacant with the exception of several concrete slabs, foundation remnants and basement areas remaining from the former site structures. The northern, western and southern Site perimeter is secured with chain-link fencing.

The eastern property line is bound in parts by a chain-link fence and/or a retaining wall and runs roughly north-south parallel to the Mad River. A strip of land between the eastern property line and the western bank of the Mad River is not part of the parcel and is identified as part of the eastern adjoining properties at 272 River Street to the northeast and 835 South Main Street to the southeast (includes the adjacent off-site dam on the Mad River). The southernmost eastern property line runs along an 8-10 foot high, stone and mortar wall which channelizes the Mad River which flows under a bridge at South Main Street.

The Site is further adjoined to the north by Brass City Harvest (359 Mill Street), to the west across Mill Street by multi-family residential buildings, and to the south by a large brick commercial/industrial building (698 South Main Street). Please note that the southern portion of the Site includes an approximately 30-foot wide parcel of land (being acquired by the City of Waterbury) which was associated with an elevated rail historically utilized by one of the local brass mills.

777 South Main Street, Waterbury, CT

WSP

November 2024

The DEEP groundwater classification for the area encompassing the Site is “GB”, which indicates that the water quality is presumed to not be suitable for drinking without treatment due to historical industrial activity, urban land uses, and the potential for waste discharges, spills or other land-use impacts to groundwater. The Mad River, which is located offsite and to the east of the Site has a surface-water quality classification of “B”, which designates uses for industrial and agricultural water supply, recreation, navigation and habitat for fish and other aquatic life and wildlife.

2.3 GEOLOGY

Waterbury lies in the eastern edge of the Western Connecticut Highlands (Gates and Martin, 1967). Surficial materials at the Site are mapped as alluvium overlying sand (Stone, J. R. 1992), sand overlying gravel (west) and post-glacial alluvium over undifferentiated coarse deposits (east) (CT ECO).

The above deposits may overlie till and are known to be overlain by imported fill materials. Bedrock beneath the Subject Property is mapped as Waterbury Gneiss, a gray to dark gray fine- to medium-grained schist to gneiss (Rodgers, 1985).

2.4 SITE SOIL

The soils, mapped as “Urban Land”, are loamy and have anthropogenic influences. Site historical operations have resulted in fill material below the surface across the Site. Fill consists of fine to medium sand with gravel and debris, such as brick, glass, wood, metal, ash, plastic, and concrete. During the August 2024 soil boring program, pockets of non-native fill (bricks, concrete, etc.) were encountered throughout the southern portion of the Site.

2.5 HYDROGEOLOGY

Site topography slopes down to the east and south east across the Site and is relatively flat on the southernmost portions of the Site. Groundwater flow direction has been calculated to the east and southeast (Leggette Brashears and Graham, 2016). Depth to shallow overburden groundwater was measured as 9.41 to 11.92 feet below ground surface (bgs).

2.6 SURROUNDING LAND USE

The area surrounding the Site is developed with a mixture of multi-family residential, commercial, industrial, and undeveloped properties. The Site is adjoined by an undeveloped strip of land (includes the adjacent dam on the Mad River) associated with 272 River Street to the northeast and 835 South Main Street to the southwest along the Mad River to the east. The Site is further adjoined to the south across South Main Street by a large brick commercial/industrial building (698 South Main), to the west across Mill Street by multi-family residential buildings, and to the north by Brass City Harvest (359 Mill Street).

Please note that the southern portion of the Site is bisected by an approximately 30-foot-wide parcel of land (not owned by the City of Waterbury) which was associated with an elevated rail historically utilized by one of the local brass mills.

777 South Main Street, Waterbury, CT

WSP

November 2024

3 PREVIOUS INVESTIGATIONS

3.1 INITIAL SITE ASSESSMENTS

A Targeted Brownfields/Phase I Environmental Site Assessment (ESA) completed by Advanced Environmental Solutions, Inc. (AES) in June 2009 for both parcels and identified 10 recognized environmental conditions (RECs) on the Site. RECs from the report included: 1) industrial use could have caused impacts to soil and/or groundwater; 2) oil staining of soil south of the buildings of the Property in the reported area of an abandoned underground storage tank (UST); 3) non-native fill and possible foundry sand; 4) possible asbestos in former basements; and 5) potential off-site sources of contamination.

A Phase I ESA completed for WDC by WSP (formerly Leggette, Brashears and Graham, Inc.

(LBG)) in July 2016 (“Phase I Environmental Site Assessment, 777 South Main Street, Waterbury, Connecticut”) outlined 8 areas of concern (AOCs) indicative of a release or material threat of release of hazardous substances at/to the Site. These AOCs covered the historical industrial use of the Site, abandoned UST, oil contamination on the surface and free-phase petroleum observed in a groundwater-monitoring well, possible foundry sand, other fill material, and possible asbestos in basement areas.

3.2 INITIAL SITE CHARACTERIZATION

A Phase II/III ESA was completed by WSP (formerly LBG) in October 2016 (“Phase II/III

Investigation Report, Waterbury Development Corporation, 777 South Main Street, Waterbury, Connecticut”). This investigation targeted 10 AOCs and groundwater concerns, finding evidence of releases at 6 of the AOCs. The investigation included soil borings, test pits, concrete sampling, and the collection of groundwater samples from existing and several newly installed groundwater monitoring wells. PCBs (a maximum concentration of 498 mg/kg were identified in generally shallow soils on the southern and southwestern portion of the Site. As summarized in Table 1, of the 97 soil samples analyzed, 72 samples had detections of PCBs. A total of 59 exceeded the RDEC and 27 of those also exceeded the I/C DEC of 10 mg/kg. A total of 16 were equal to or exceeded the 50 mg/kg threshold generally considered PCB remediation waste. All but 7 of the detections were from soil samples from the top two feet of soil.

Nobis Engineering Inc. completed a Final Targeted Brownfields Assessment (TBA) in March 2018 to collect information and determine the extent of the PCB contamination, evaluate risks posed by this contamination, and develop preliminary cleanup alternatives and costs for the Site. Investigations found a range of PCB concentrations, with elevated PCBs located around the former boiler plant and engine room at the southern mill complex. PCBs appeared to be most concentrated in the upper 2 ft of soil in the eastern half of the southern portion of the Site and decrease with depth. As summarized in Table 2, of the 286 soil samples analyzed, 163 samples had detections of PCBs.