Phase II_III Site Investigation prepared by BL April 2019.pdf

355 Research Parkway ▪ Meriden, CT 06450 ▪ T (203) 630-1406 ▪ F (203) 630-2615 ▪ www.blcompanies.com

PHASE II / III SITE INVESTIGATION

Allyn Street Assemblage Hartford, Connecticut

Prepared for:

Mr. Garrett Heher Director of Capital Projects

Shelbourne Global Solutions, LLC 20 Church Street

Hartford, CT 06103

Prepared By:

BL Companies, Inc.

355 Research Parkway Meriden, Connecticut 06450

April, 2019 BL Companies Project No. 1800389

An Employee-Owned Company

This report was prepared by the individuals listed below. Any questions or comments regarding the information provided herein should be directed to these individuals.

Prepared by:

Wesley Johnson Project Scientist

Reviewed by:

Timothy Myjak, LEP Senior Project Manager

Sam Haydock, MS, LEP Principal

TABLE OF CONTENTS

Section Description Page

1.0 INTRODUCTION

1.1 Site Description

1.2 Site History

2.0 ENVIRONMENTAL SETTING

2.1 Geology and Hydrogeology

2.2 Groundwater and Surface Water

3.0 PREVIOUS INVESTIGATIONS

4.0 REGULATORY FRAMEWORK

4.1 Connecticut Transfer Act

4.2 Remediation Standard Regulations

5.0 CONCEPTUAL SITE MODEL

5.1 Data Quality Objectives

5.2 AOC 1 – Former Gasoline Service Station

5.3 AOC 2 – Former Steam Laundry Facility

5.4 AOC 3 – Former Auto Repair/Sales and Machine Shop

5.5 AOC 4 – Former Repair and Body Shop

5.6 AOC 5 – Former Car Rental Facility, Dress Factory, and Printing Operation…………………………………………………………………...13

5.7 AOC 6 – Former Gengras Motor Cars, Universal Auto Co., and Clothing Factory

5.8 AOC 7 – Former Battery Station, Sheet Metal Works, and

Woodworking Facility

5.9 AOC 8 – Urban Fill of Unknown Origin (Site-wide)

6.0 PHASE II / III SITE INVESTIGATION

6.1 Summary of Work and Rationale

6.2 Analytical Results and Comparison to RSR Criteria

7.0 CONCLUSIONS AND RECOMMENDATIONS

7.1 Summary of Findings

7.2 Recommendations

7.3 CTA Obligations

7.4 Potential Remedial Options

8.0 LIMITATIONS

TABLE OF CONTENTS

(continued)

APPENDICES

Appendix A Boring Logs, Well Completion Diagrams, and Test Pit Logs

Appendix B Site Plans Site Location Map Site Plan with AOCs (SP-01) Site Investigation Plan (SI-01) GPR Survey Transect Map (GPR-01) Areas of Urban Fill (SI-02) Soil ETPH and PAH RSR Exceedances (SI-03) Soil VOC and Metals RSR Exceedances (SI-04) Groundwater Contour Plan (GW-01)

Appendix C Tables Table 1 – Soil Analytical Data Table 2 – Groundwater Analytical Data

Appendix D Laboratory Analytical Data Reports

Phase II / III Site Investigation 1 1800389 Allyn Street Assemblage, Hartford, Connecticut DRAFT April 2019

1.0 INTRODUCTION

BL Companies was retained by Shelbourne Global Solutions, LLC (Shelbourne) to complete a Phase II / III Site Investigation (SI) at the Allyn Street Assemblage, in Hartford, Connecticut. The Site (Allyn Street Assemblage) consists of the following parcels:

• 329 Church Street,

• 339 Church Street,

• 98 High Street,

• 106 High Street,

• 112 High Street,

• 122 High Street,

• 108 Allyn Street,

• 112 Allyn Street,

• 128 Allyn Street, and

• 154 Allyn Street (combined with 180 Allyn Street but recorded as 154).

The Phase II / III SI has been completed as part of due diligence associated with the potential acquisition of the Site. BL Companies previously completed a Phase I Environmental Site Assessment (ESA) for the Site, reported dated December 2018.

Based on the Phase I ESA findings, BL Companies identified areas of concern (AOCs), as described by the Connecticut Department of Energy and Environmental Protection (CTDEEP) Site Characterization Guidance Document (SCGD). AOCs have been identified associated with former Site industrial / commercial activities and operations.

Some of the AOCs were investigated as part of the initial Phase II SI, during which time the presence of releases was identified. Please note that a Phase II SI report had not been finalized, rather those investigation activities have been incorporated into this Phase II / III SI report.

The purpose of this Phase II / III SI was to continue to evaluate the presence and or absence of release (s) at Recognized Environmental Conditions (RECs) and AOCs, and to the extent technically prudent, within the constraints of the provided scopes of work, delineate the extent of environmental impacts for the purpose of redevelopment planning.

This Phase II / III SI was conducted in general accordance with standard and accepted practices and the CTDEEP SCGD dated September 2007, revised December 2010, and as such, RECs will be referenced to as AOCs for the remainder of this document. The results of BL Companies’ Phase II / III SI and the regulatory implications are discussed in this report.

1.1 Site Description

The Site consists of ten currently structurally undeveloped contiguous parcels, totaling

2.16 acres, located at 329 Church Street, 339 Church Street, 98 High Street, 106 High Street, 112 High Street, 122 High Street, 108 Allyn Street, 112 Allyn Street, 128 Allyn Street, and 154 Allyn Street. The Site is generally bound by Church Street to the north, Allyn Street to the south, and High Street to the west. The eastern portion of the Site

Phase II / III Site Investigation 2 1800389 Allyn Street Assemblage, Hartford, Connecticut April 2019 abuts mixed use commercial development including a church and restaurants. The Site consists of a secure parking area with pay gate access points from each street, and a small, attendant station along the south central Allyn Street road frontage. The Site is currently utilized as a parking service managed by Propark America, and is situated in an area primarily surrounded by mixed commercial and residential land usage. See Figure 1 (Site Location Map) and the Site Plan With AOCs (SP-01) included in Appendix A.

1.2 Site History

Based on historical sources reviewed, and municipal and state records, the Site was developed as early as 1885 with residential and educational structures. By 1900, a blacksmith and a wagon working shop were present at 128 Allyn Street and a carriage repository was located at 112 Allyn Street.

By 1950, a printing operation, tire sales and service, auto sales and service, and a clothing manufacturer were located on 128 Allyn Street and 154-180 Allyn Street. A warehouse was present at 98 High Street, and a restaurant and a store were located at 112 High Street. In addition, a gas station was operating at 122 High Street, and a machine shop was present at 329 Church Street.

By 1979, 112 High Street was vacant, and a wholesale dry goods store was located at 112 Allyn Street. In 1986, an auto body operation was present at 98 High Street.

By 1992, a dress factory, a parking garage, and Universal Auto Company (auto repair and parts storage) were present at 128 Allyn Street and 154-180 Allyn Street. The YMCA and a parking garage were located on 98 High Street, and a battery station, sheet metal works, and a woodworking operation were present at 128 Allyn Street. Residential dwellings were present at 112 Allyn Street, and office and auto supplies and retail stores were located at 108 and 112 Allyn Street. A steam laundry and auto repair operations were present at 329 and 339 Church Street.

From approximately 1986 to 1988, all of buildings were demolished to make way for a proposed redevelopment project that was never built. It appears that the Site remained vacant and undeveloped for approximately 17 years. In 2005 the Site was paved and developed as a parking lot.

The Site formerly maintained heating oil and/or waste oil above-ground storage tanks (ASTs) from at least the 1920s to the 1960s associated with 98-100 High Street and 128- 150 Allyn Street. Between 1950 and 1986, the Site maintained gasoline, diesel, heating oil, and waste oil underground storage tanks (USTs), and/or hydraulic lifts associated with 112-122 High Street, 128-150 Allyn Street, 339-343 Church Street, and 154-164 Allyn Street.

Various industrial operations were identified as hazardous waste generators including High Street Mobil (aka Atlas Oil Company), Godell’s Repair and Body Shop, ISS Prudential Maintenance Services, Inc., Driscoll Motors, Inc., and the Hertz Corporation.

Phase II / III Site Investigation 3 1800389

Based on Information on file at the Connecticut DEEP, the parcels, with the exception of 108 Allyn Street and 112 Allyn Street, have been the subject of Form III filings under the Connecticut Transfer Act (CTA) and likely will be subject to its requirements in the event of a future transfer.

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2.0 ENVIRONMENTAL SETTING

2.1 Geology and Hydrogeology

Geologically, the Site is located in the Central Lowlands Physiographic Province of Connecticut and is mapped to be underlain by the Portland Arkose, consisting of reddish-brown arkose (brownstone) (Rodgers, 1985). Bedrock outcrops are not present at the Site and was not encountered during this investigation.

According to the "Surficial Materials Map of Connecticut", dated 1992, surficial materials within the project area are anticipated to consist of fines (very fine sand, silt, and clay), which are composed of well sorted, thin layers of alternating silt and clay, or thicker layers of very fine sand and silt. Very fine sand commonly occurs at the surface and grades downward into rhythmically bedded silt and clay varves (lake bottom deposits). Based on observations during test pit excavation and boring installation, surficial materials consist of urban fill over the anticipated native material. The depth of the urban fill ranged from as shallow as 0’ below grade surface (bgs) to as deep as 10’ bgs. Material beneath the urban fill consists of reddish brown to brown silt and clay with varying amounts of sand, gravel, and cobbles. Boring and Test Pit logs are included as Appendix A.

According to the USGS 7.5-Minute Topographic Map of Hartford, Connecticut, the Site is relatively flat and is situated at an elevation of approximately 60 feet above mean sea level. Topography in the vicinity of the Site generally slopes to the southeast towards the Connecticut river, approximately 3,200 feet from the Site. Groundwater elevations determined during this Phase II / III Site investigation infer that the groundwater flow direction is to the southeast.

2.2 Groundwater and Surface Water

According to the CTDEEP mapping, groundwater beneath the Site is classified as GB.

The GB classification indicates that groundwater at the Site is presumed unsuitable for direct human consumption without treatment. According to CTDEEP mapping, the Site is not located within an Aquifer Protection Area.

Surface water bodies were not observed on the Site. The Park River, a river that has been culverted and flows beneath the City of Hartford, is located approximately 1,700 feet to the south-southwest of the Site. As previously discussed, the Connecticut River is located approximately 3,200 feet to the southeast of the Site. Both the Park River and the Connecticut River are classified as “SB” surface water bodies by the CTDEEP. Class SB surface waters are designated for use as marine fish, shellfish and wildlife habitat, shellfish harvesting for transfer to approved areas for purification prior to human consumption, recreation, industrial and other legitimate uses including navigation.

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3.0 PREVIOUS INVESTIGATIONS

Phase I Environmental Site Assessment, Allyn Street Assemblage, Hartford, Connecticut, prepared by BL Companies, December 13, 2018.

According to the Phase I ESA conducted by BL Companies in December 2018, the Site was developed as early as 1885 and has an extended history of industrial operations including blacksmith shop, wagon working shop, carriage repository, dress factory, clothing manufacturing, parking garage, auto repair and parts storage, sheet metal works, woodworking, auto supplies and retail stores, steam laundry, printing operation, tire sales and service, and warehouse. Gasoline, heating oil and waste oil USTs, hydraulic lifts, and heating oil ASTs have been present in the past at the Site.

Various operations were hazardous waste generators, and The Hertz Corporation, Gadell's Repair & Body Shop, Inc. at 98 High Street, ISS Prudential Maintenance Services, Inc. at 100 High Street, and Driscoll Motors, Inc. at 132 Allyn Street were identified in 1986 as Establishments with Form III filings. In addition, the Atlas Oil Company at 112 and 122 High Street was identified as an Establishment in 1986 with a Form III filing. Correspondence from a legal firm indicates that 128-164 Allyn Street, 84- 110 High Street, and 317 to 331 Church Street are Establishments.

The report identified the following operational RECs, considered AOCs by the CTDEEP, in connection with the Site:

• The Site has historically operated with a gas station at 112-122 High Street, auto repair, a printing operation, and manufacturing operations at 128 and 154-180 Allyn Street, auto body operations at 98 High Street, and a machine shop and auto repair at 329 Church Street. Limited information was available regarding former Site processes, potential chemicals utilized, and potential or actual wastes generated. Although no documented releases were reported to the CTDEEP, the Site maintained various gasoline, heating oil, and waste oil USTs and heating oil ASTs, and several releases of gasoline and heating oil were identified in municipal records. Hazardous waste manifests document wastes transported from 1986 to 1991 associated with the auto body operation and the gas station.

Based on the Form III filing for 112 and 122 High Street, this portion of the Site is considered an "Establishment" due to historic Site operations. In addition, correspondence from a legal firm to the CTDEEP in 1986 indicates that a subsequent Form III was filed for 128-164 Allyn Street, 84-110 High Street, and 317 to 331 Church Street. Based on the correspondence, the Site is considered an Establishment with the exception of the 108 Allyn Street and 112 Allyn Street parcels. The Site would likely be subject to the legal and technical requirements of the CTA in the event of a transfer.

As part of the initial Phase II and progressive Phase III SI activities BL Companies developed and updated a Conceptual Site model (CSM), which identified the following operational and use AOCs at the Site. AOCs are defined by the CTDEEP as “Locations or areas at a site where hazardous waste and or hazardous substances (including

Phase II / III Site Investigation 6 1800389 petroleum products) have been or may have been used, stored, treated, handled, disposed, spilled, and/or released to the environment”.

• AOC 1: Former Gasoline Service Station.

• AOC 2: Former Steam Laundry Facility.

• AOC 3: Former Auto Repair/Sales and Machine Shop.

• AOC 4: Former Repair and Body Shop.

• AOC 5: Former Car Rental Facility, Dress Factory, and Printing Operation.

• AOC 6: Former Gengras Motor Cars, Universal Auto Co., and Clothing Factory.

• AOC 7: Former Battery Station, Sheet Metal works, and Woodworking Facility.

• AOC 8: Urban Fill of Unknown Origin (Site-wide).

• AOC 9: Northwestern Area of Interest

The CSM process was used to develop an investigative approach in order to characterize each AOC.

As part of the initial January 2019 Phase II SI activities, BL Companies advanced a total of 39 soil borings and installed five groundwater monitoring wells in order to collect soil and groundwater samples for analysis for the presence of specific constituents of concern (COCs) identified in the preliminary CSM. In addition, BL Companies performed a ground penetrating radar (GPR) survey of the Site to determine if potential former USTs identified during the Phase I ESA remain at the Site. Five potential USTs, one potential former dispenser, and two areas of interest were identified during the GPR Survey and are depicted on the Site Plan With AOCs (SP-01) and Site Investigation Plan (SI-01) included in Appendix B. Based on the results of the initial Phase II SI activities, releases of regulated compounds had been identified at AOCs 1 through 8. At that time AOC 9 had not been investigated. For comparison purposes, soil concentrations exceeding CT Remediation Standard Regulation (RSR) criteria were identified at soil samples collected from AOC-1, AOC-2, AOC-3, AOC-4, and AOC-6. In addition, releases of COCs were identified in groundwater within the area of AOC-1, AOC-3, and AOC-6. These releases appeared to be due to a combination of impacted urban fill of unknown origin, and/or historical Site usage. Urban fill of unknown origin was observed throughout the majority of the Site. Much of the fill appears to be impacted with regulated COCs at concentrations exceeding RSR criteria.

Based on the results of the preliminary Phase II SI, BL Companies recommended the completion of additional Phase II / III SI activities to determine the presence or absence of historical USTs identified during the GPR survey, to complete the evaluation of potential release areas, and to determine the nature and extent of releases identified.

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4.0 REGULATORY FRAMEWORK

4.1 Connecticut Transfer Act

Connecticut General Statute (CGS) Section 22a-134 is known as “The Connecticut Transfer Act” (CTA) and regulates the transfer, investigation and remediation of Hazardous Waste Establishments. An Establishment is defined as any real property at which or any business from which:

• on or after November 19, 1980, there was generated, except as a result of remediation of polluted soil, groundwater or sediment more than 100 kilograms of hazardous waste in any one month;

• hazardous waste generated at a different location was recycled, reclaimed, reused, stored, handled, treated, transported or disposed of;

• the process of dry cleaning was conducted on or after May 1, 1967;

• furniture stripping was conducted on or after May 1, 1967; or

• a vehicle body repair facility was located on or after May 1, 1967.

Facilities that are considered Establishments under the CTA are subject to certain reporting requirements to the CTDEEP when a transfer of ownership occurs. One of four filing forms (Form I, II, III, IV) and an ECAF must be submitted to the CTDEEP.

As identified in the Phase I ESA, with the exception of 108 and 112 Allyn Street, the remaining parcels were identified as Establishments with Form III fillings in 1986. The Site Establishment parcels would therefore likely be subject to the legal and technical requirements of the CTA in the event of a transfer. BL Companies is not aware of other environmental investigation or remediation completed at the Site subsequent to the 1986 filings under the CTA. It appears that the CTA obligations associated with the previous Form III filings remain open.

In order to achieve compliance with the CTA, and achieve CTDEEP approval or verification by an Licensed Environmental Professional (LEP), it is necessary to demonstrate that potential release areas at the Site have been investigated in accordance with standard and prevailing guidelines, and that remediation (if necessary) has been completed, including any post-remediation groundwater monitoring in compliance with the RSRs, which are further discussed below.

4.2 Remediation Standard Regulations

The CTDEEP has promulgated the RSRs, Sections 22a-133k-1 through 3 of the Regulations of the Connecticut State Agencies (RCSA), that specify the allowable levels of regulated compounds in soil and groundwater for both GA (groundwater presumed drinkable without treatment) and GB (presumed unsuitable for drinking without treatment) groundwater classification areas.

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4.2.1 Soil Criteria

The RSRs define two criteria that apply to soil: the Direct Exposure Criteria (DEC) and the Pollutant Mobility Criteria (PMC). The DEC defines the maximum level of regulated compounds allowed in soil to a depth of 15 feet bgs without posing a threat due to direct human exposure, while the PMC sets the maximum level of regulated compounds allowed in soil without posing a threat to groundwater quality. Each criterion is further divided into two categories; the DEC is based upon Site usage (i.e., residential or industrial/commercial use), while the PMC is based on the groundwater classification (i.e., GA/GAA or GB). The Site is located in a GB groundwater classification area and therefore is required to meet the GB PMC.

The residential DEC must be met if a Site is to be used for residential purposes. The CTDEEP and the RSRs define “residential activity” to include any activity related to a residence or dwelling, or to a school, hospital, day care center, playground, or outdoor recreation area. If a Site or property is not to be used for residential purposes, then the industrial/commercial DEC may be met if an Environmental Land Use Restriction (ELUR) is filed for the Site. The ELUR would limit the Site to only industrial or commercial usage.

The current use of the Site meets the definition of industrial/commercial.

The DEC does not apply if soil meets the definition of “inaccessible,” and the PMC does not apply if soil meets the definition of “environmentally isolated.” In either case, an ELUR is required.

Soil can be rendered “inaccessible” if the impacted soil is covered by four feet of clean fill (non-polluted material), or covered by two feet of clean fill and a minimum of three inches of asphalt, or covered by a building or other permanent structure. A 2013 Amendment to the RSRs allows for fill material which has been impacted by “semi-volatile substances or petroleum hydrocarbons that are normal constituents of bituminous concrete” and/or metals that are less than two times the DEC to be capped with asphalt and deemed inaccessible, even at depths between 0-2’ bgs. The ELUR put in place during this scenario would not need the CTDEEP approval, financial assurance, or reporting requirements associated with an engineered control as it would have prior to the amendment.

Soils that are isolated beneath a building or other impermeable structure may be considered “environmentally isolated,” such that with the use of an ELUR, the PMC does not apply. Asphalt is not considered impermeable and cannot be used to render soil environmentally isolated.

Additionally, the RSRs also provide several self-implementing options, as well as a mechanisms for CTDEEP approval of variances to the published RSRs, for the remediation of regulated compounds in soil.

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4.2.2 Groundwater Criteria

The RSRs define three criteria that apply to groundwater: the groundwater protection criteria (GWPC), the surface water protection criteria (SWPC), and the groundwater volatilization criteria (GWVC). The GWPC defines the maximum levels of regulated compounds allowed in groundwater for protection of the groundwater as a potable water source. In areas that are classified as GA or GAA, the remediation goal may be to achieve the GWPC or more stringent background conditions, depending on if municipal water is available for all area residents or if a public water supply is nearby. The GWPC generally does not apply to GB areas unless water supply wells are located within the vicinity of an identified plume. The Site is located in a GB groundwater classification area, and potable supply wells are not suspected to be present in the Site vicinity, therefore the GWPC does not appear to apply to the Site.

The SWPC applies to impacted groundwater that is discharging to a surface water body, including wetlands, streams, rivers, ponds, lakes, and Long Island Sound. One standard has been set for all surface water bodies, regardless of quality classification. The SWPC specifies the levels of compounds allowable in groundwater just prior to discharging into surface water. Compliance with the SWPC is established at the point at which the plume discharges to the surface water body. The RSRs also allow the evaluation of an alternative SWPC, based on available dilution in the receiving water body. Surface water has not been identified on or adjacent to the Site.

The GWVC sets the allowable levels of volatile organic compounds (VOCs) in groundwater that is less than 15 feet bgs. The GWVC is designed to protect humans from exposure to VOCs present in shallow groundwater. Residential and industrial/commercial GWVC have been established, with the residential GWVC being more stringent, and the industrial/commercial GWVC requiring the use of an ELUR. The GWVC may not have to be met if monitoring of soil vapor above the water table or indoor air quality demonstrates that there is no exposure hazard.

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5.0 CONCEPTUAL SITE MODEL

BL Companies utilized the Conceptual Site Model (CSM) approach for the Site based upon the geology, hydrogeology, the historical use of the Site as identified in the Phase I ESA, and the results of the progressive Phase II / III SI. A CSM is a description of the environmental system at a Site that provides a framework for communicating the rationale for the Site investigation process. The CSM describes potential release areas as well as release mechanisms, contaminant fate and transport characteristics, and potential migration pathways at the Site.

The following AOCs, representative of historic uses and operations, have been identified at the Site. Since the Site parcels had been redeveloped and / or repurposed over several decades ago, operations ceased and structures completely razed by the late 1980’s, there was limited specific operational information available for parcels specific to the use, storage, and or disposal of chemicals and petroleum products. As such, parcel-specific operations have been lumped into individual parcel operational AOCs :

• AOC 1: Former Gasoline Service Station Operations.

• AOC 2: Former Steam Laundry Facility Operations.

• AOC 2a: Former Potential UST.

• AOC 3: Former Auto Repair/Sales and Machine Shop Operations.

• AOC 3a: Former Potential UST.

• AOC 4: Former Repair and Body Shop Operations.

• AOC 5: Former Car Rental Facility, Dress Factory, and Printing Operation.

• AOC 6: Former Gengras Motor Cars, Universal Auto Co., and Clothing Factory Operations

• AOC 7: Former Battery Station, Sheet Metal works, and Woodworking Facility Operations.

• AOC 7a: Former Potential USTs and Areas of Interest.

• AOC 8: Urban Fill of Unknown Origin (Site-wide).

• AOC 9: Northwestern Area of Interest.

The CSM was used to develop an investigative approach in order to characterize each AOC. The goal of the Phase II SI activities was to determine the presence or absence of a release (s) of regulated compounds at the Site. The goal of the Phase III SI activities was to delineate, as technically feasible within the scopes of work, releases of regulated COCs detected in soil and / or groundwater. Test pits, soil borings and groundwater monitoring wells were utilized to collect soil and groundwater samples for analysis for the presence of COCs identified during the CSM process.

The location of the AOCs are depicted on the Site Plan (SP-01) and Site Investigation Plan (SI-01) included in Appendix B.

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5.1 Data Quality Objectives

Development, revision and validation of the CSM process are dependent upon the complexity of the Site conditions and the project-specific data quality objectives (DQOs) that are established to adequately characterize the Site. The DQOs for the Site characterization process are developed to ensure data of sufficient quality and quantity are collected to support decisions and conclusions made during Site characterization and to aid in the ultimate validation of the CSM.

DQOs are statements that clarify objectives, define the appropriate type and quantity of data to be collected, establish the appropriate conditions for data collection, and specify acceptable levels of error and laboratory reporting levels that will be used as the basis for establishing the quantity and quality of the data needed to support decision made based upon the use of that data. The DQO process used on this project was developed to help guide data collection activities, develop a defensible rationale for collecting samples and to ensure that the data used in the decision-making process was appropriate for the intended use.

5.2 AOC 1: Former Gasoline Service Station Operations

Historical file review conducted during the Phase I ESA indicated that 112-122 High Street formerly contained a gasoline service station. This portion of the Site is listed with one 1,000-gallon waste oil UST in 1937, one waste oil UST abandoned in 1958, and two 4,000-gallon gasoline USTs in 1958. The 4,000-gallon USTs reportedly replaced two 1,000-gallon USTs in 1958. In addition, one 275-gallon heating oil tank from 1940 was replaced with a 500-gallon tank in 1959. A 1970 Building Record indicated that the Site maintained two 4,000-gallon and one 2,000-gallon gasoline USTs. The Site was identified as High Street Mobil in 1979 and one 10,000-gallon gasoline UST was scheduled to be installed. In 1982, the Site is listed with one 4,000-gallon waste oil UST, one 4,000-gallon gasoline UST, and one 10,000-gallon gasoline UST.

An April 1986 Underground Storage Facility Notification form (EPHM-6) notes the registration of one 10,000-gallon gasoline UST installed in 1982, two 4,000-gallon gasoline USTs installed in 1961, and one 550-gallon waste oil UST installed in 1961 as currently in use. One 1,000-gallon unidentified UST was listed as abandoned-in-place in 1969.

An additional EPHM-6 form, dated December 1986, indicated that the USTs were removed in 1986. A rough sketch included with the form depicts the gas station in the northwest corner of the Site, at the intersection of High Street and Church Street. The gasoline UST locations are illustrated as adjacent to the building in the northwest corner and the waste oil UST is in the northwestern-most corner of the Site.

This area was investigated during the GPR survey. Anomalies or signatures were not identified within the AOC which may be considered representative of in place USTs.

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Potential Release Mechanisms: Spills or leaks from failure of the tanks or discharge pipes or spills during filling of the tanks.

Potential Migration Pathways: To surficial soil or subsurface soil, then downward through the subsurface soils towards the water table.

Constituents of Concerns: Volatile Organic Compounds (VOCs), Polyaromatic Hydrocarbons (PAHs), Extractable Total Petroleum Hydrocarbons (ETPH), polychlorinated biphenyls (PCBs), and Metals.

5.3 AOC 2: Former Steam Laundry Facility Operations

Historical file review and historical Sanborn Fire Insurance maps depict a steam laundry facility located at 339-343 Church Street circa 1922-1950. In addition, prior to drilling, a GPR utility survey was conducted and a potential UST / area of interest, identified as AOC 2a, was discovered adjacent to the southwestern corner the former steam laundry facility building. An application for a heating permit indicates the facility maintained a boiler room.

According to the Hartford Fire Marshal, a heating oil leak in the boiler room of “Sanitary Laundry” is reported in 1965 and 1966 due to an overfill. Additional information pertaining to the steam laundry facility operational practices and procedures was not available for review. Indication of any dry-cleaning operations at this facility had not been identified.

Potential Release Mechanisms: Spills or leaks from failure of the tanks or discharge pipes or spills during filling of the tanks. Spills or leaks from potential waste containment systems.

Potential Migration Pathways: To surficial soil or subsurface soil, then downward through the subsurface soils towards the water table. Through cracks or imperfections in the building floor, to underlying soils, then downward through subsurface soils to the water table.

Constituents of Concerns: VOCs, PAHs, and ETPH.

5.4 AOC 3: Former Auto Repair/Sales and Machine Shop Operations

Historical file review and historical Sanborn Fire Insurance maps depict an Auto Repair/Sales and Machine Shop at 329-331 Church Street, located in the northeastern portion of the Site from at least 1922 to at least 1950. In addition, during the GPR survey, a possible UST/ area of interest, identified as AOC 3a, and dispenser were discovered to the east of the former building. A plan dated April 1987 depicts a fuel fill and gas pump in this general vicinity. However, they appear to be associated with the factory to the south, located at 128-150 Allyn Street. Additional information pertaining to the operational practices and procedures for this facility was not available for review.

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Potential Release Mechanisms: Spills or leaks from failure of equipment and storage containers, and spills or leaks from failure of the tanks or discharge pipes or spills during filling of the tanks, the possibility of vehicle lift systems that could have released hydraulic fluids.

Potential Migration Pathways: Through cracks or imperfections in the concrete floor, to underlying soils, then downward through subsurface soils to the water table, and to surficial soil or subsurface soil, then downward through the subsurface soils towards the water table.

Constituents of Concerns: VOCs, PAHs, ETPH, PCBs, and metals.

5.5 AOC 4: Former Repair and Body Shop Operations

Historical file review and historical Sanborn Fire Insurance maps depict Gadell’s Repair and Body Shop, circa 1978-1988, located at 98-100 High Street. In addition, this portion of the Site is listed with one 550-gallon UST, one pump, one 275-gallon tank, and one 1,000-gallon UST reportedly associated with Intertown Motors, which occupied the Site from 1931 to 1965. A Building Record from 1971 identified a 1,000-gallon heating oil tank on the north side of the Site building. In addition, the tenant was listed with a 1,000-gallon heating oil UST and a 275-gallon waste oil aboveground storage tank (AST). Additional information pertaining to the operational practices and procedures for this facility were not available for review.

This area was investigated during the GPR survey. Anomalies or signatures were not identified within the AOC representative of current USTs systems.

Potential Release Mechanisms: Spills or leaks from failure of equipment and storage containers, and spills or leaks from failure of the tanks or discharge pipes or spills during filling of the tanks, the possibility of vehicle lift systems that could have released hydraulic fluids.

Potential Migration Pathways: Through cracks or imperfections in the concrete floor, to underlying soils, then downward through subsurface soils to the water table and/or to surficial soil or subsurface soil, then downward through the subsurface soils towards the water table.

Constituents of Concerns: VOCs, PAHs, ETPH, PCBs and metals.

5.6 AOC 5: Former Car Rental Facility, Dress Factory, and Printing Operations

Historical file review and historical Sanborn Fire Insurance maps depict Hertz Rent a Car and a dress factory associated with 154-164 Allyn Street circa 1950s-1990s. In addition, a printing operation was associated with 154-164 Allyn Street circa 1950s. This portion of the Site is listed with one 1,000-gallon UST, one 550-gallon UST, and two pumps.

Permits believed to be associated with fuel storage and dispensing were approved in

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October 1920, March 1921, March 1941, November 1955, and June 1965. The 1965 permit notes the replacement for the existing pump and tank. A permit listing for 160 Allyn

Street notes the presence of one 1,000-gallon UST and one pump approved in

September 1931. In addition, in 1955, replacement of a 1,000-gallon gasoline tank was approved for Hertz-U-Drive. In 1964, a 550-gallon gasoline tank is noted on the Site. In

1969, a gasoline spill was noted in the Hertz Garage. In 1979, Incident No. 79-067-12 is listed for a release of gasoline at Hertz. In 1982, one 550-gallon gasoline UST, one 1,100-gallon gasoline UST, and a dispenser are noted as present on the Site for Hertz.

Additional information pertaining to the operational practices and procedures for these facilities was not available for review. This area was investigated during the GPR survey and anomalies were not identified, suggesting that the above-mentioned USTs have been removed.

Potential Release Mechanisms: Spills or leaks from failure of equipment and storage containers, and spills or leaks from failure of the tanks or discharge pipes or spills during filling of the tanks, the possibility of vehicle lift systems that could have released hydraulic fluids.

Potential Migration Pathways: Through cracks or imperfections in the concrete floor, to underlying soils, then downward through subsurface soils to the water table and/or to surficial soil or subsurface soil, then downward through the subsurface soils towards the water table.

Constituents of Concerns: VOCs, PAHs, ETPH, PCBs, and metals.

5.7 AOC 6: Former Gengras Motor Cars, Universal Auto Co., and Clothing Factory Operations

Historical file review and historical Sanborn Fire Insurance maps depict Gengras Motor

Cars, Circa 1986, a clothing factory, circa 1950, and Universal Auto Company, Circa

1922-1950, associated with 128-150 Allyn Street. This portion of the Site is listed with one 1,000-gallon UST and one pump in 1920. A factory is noted in 1949 on the third floor of the Site building, and a proposed machine shop for the second floor was noted in 1950.

Two unpermitted oil burners are noted in 1955, and an oil spill was reported in 1957. The

Site is listed with two 5,000-gallon steel gasoline and diesel USTs in 1981. A Building

Record in 1973 notes the presence of one 275-gallon heating oil tank and one 1,100-gallon heating oil tank in the basement of the Site building.

An EPHM-6 form on file at the CTDEEP dated July 23, 1986 notes the registration of one

3,000-gallon gasoline UST and one 5,000-gallon diesel UST, installed in 1979, and one

1,000-gallon waste oil UST, installed in the 1940s, as currently in use. A drawing depicts the entire Site and the locations of the USTs in the southeast corner of the Site. Additional information pertaining to the operational practices and procedures for these facilities was not available for review.

Phase II / III Site Investigation 15 1800389

This area was investigated during the GPR survey. One potential UST anomaly location was identified at the boundary between AOC-6 and AOC-7. The anomaly was investigated as part of AOC-7. Other anomalies or signatures were not identified within

AOC-6.

Potential Release Mechanisms: Spills or leaks from failure of equipment and storage containers, spills or leaks from failure of the tanks or discharge pipes or spills during filling of the tanks, and the possibility of vehicle lift systems that could have released hydraulic fluids.

Potential Migration Pathways: Through cracks or imperfections in the concrete floor, to underlying soils, then downward through subsurface soils to the water table and/or to surficial soil or subsurface soil, then downward through the subsurface soils towards the water table.

Constituents of Concerns: VOCs, PAHs, ETPH, PCBs, and metals.

5.8 AOC 7: Former Battery Station, Sheet Metal Works, and Woodworking Facility Operations

Historical file review and historical Sanborn Fire Insurance maps depict battery station, a sheet metal works, and a woodworking business circa 1922 associated with 120-124 Allyn Street located in the southeastern portion of the Site. In addition, during the GPR utility survey, three potential USTs and one area of interest, identified as AOC 7a, was discovered. Additional information pertaining to the operational practices and procedures for these facilities were not available for review.

Potential Release Mechanisms: Spills or leaks from failure of equipment and storage containers, and spills or leaks from failure of the tanks or discharge pipes or spills during filling of the tanks.

Potential Migration Pathways: Through cracks or imperfections in the concrete floor, to underlying soils, then downward through subsurface soils to the water table and/or to surficial soil or subsurface soil, then downward through the subsurface soils towards the water table.

Constituents of Concerns: VOCs, PAHs, ETPH, and metals.

5.9 AOC 8: Urban Fill of Unknown Origin (Site-wide)

Urban fill placed at the Site is of unknown origin and composition. Urban fill is expected Site-wide.

Potential Release Mechanisms: Urban fill impacted with contaminants of concern imported and placed at the Site, and / or as the result of the demolition of Site structures.

Phase II / III Site Investigation 16 1800389

Potential Migration Pathways: Downward through subsurface soils to the water table.

Constituents of Concerns: VOCs, PAHs, ETPH, PCBs, and metals.

5.10 AOC 9: Northwestern Area of Interest

An anomaly, Area of Interest, was identified during the GPR Survey located in the northwestern portion of the Site outside of the previously identified operational AOCs. The anomaly may be associated with former structures, fill, and or USTs.

Potential Release Mechanisms: Spills or leaks from failure of the potential tanks or discharge pipes or spills during filling of the potential tanks.

Potential Migration Pathways: To surficial soil or subsurface soil, then downward through the subsurface soils towards the water table.

Constituents of Concerns: VOCs, PAHs, ETPH, PCBs, and Metals.

Phase II / III Site Investigation 17 1800389

6.0 PHASE II / III SITE INVESTIGATION

The following is a discussion of the investigation approach conducted by BL Companies as part of the Phase II / III SI completed at the Site between January 2019 and March 2019. The field investigation and sampling program described herein was designed to fulfill the DQO of determining the presence or absence of contamination in the soil and/or groundwater that may have resulted from releases of petroleum and/or hazardous substances and to determine the extent of releases of regulated compounds, as technically practicable within the scopes of work, detected in soil and groundwater for redevelopment planning. These activities included:

• Ground Penetrating Radar Survey – December 2018

• Initial Phase II SI activities – January 2019

• Follow up Phase II / III SI activities – March 2019

6.1 Summary of Work and Rationale

GROUND PENETRATING RADAR SURVEY

BL Companies mobilized a Mala HDR ground-penetrating-radar (GPR) unit to the Site on December 20, 2018. The GPR unit was utilized to determine if potential former USTs identified during the Phase I ESA remain at the Site. Due to the active use of the Site as parking area, the GPR survey was conducted after normal business hours when the parking lot was as empty as possible. However, automobiles present at the Site during the survey still impacted access to portions of the Site. A best effort was made to identify all subsurface utilities and any potential buried metallic objects present at the Site.

Approximately 103 GPR transects were made in a grid format with an average spacing between transects of 2 feet. Several image anomalies were identified during the GPR survey and were further investigated with the GPR to designate the approximate horizontal dimensions of the anomalies. Some of the anomalies had a clear parabolic signature indicative of potential USTs. In addition to the potential USTs, a possible former fuel dispenser pad was identified during the GPR survey. Finally, two less definable unknown anomalies were located during the GPR survey and were identified as areas of interest.

The GPR transects, potential USTs, potential former fuel dispenser pad, and areas of interest are depicted on the GPR Survey Transect Map (GPR-01) included in Appendix B.

Phase II SI

BL Companies mobilized a track-mounted Geoprobe 7822DT drill rig operated by Cummins Envirotech, Inc. (CEI) on January 2, 3, and 4, 2019, to advance soil borings and install groundwater monitoring wells at the Site. A total of 39 soil borings, identified as SB-1 through SB-39, and five groundwater monitoring wells, identified as MW-1

Phase II / III Site Investigation 18 1800389 through MW-5, were installed at the Site. Soil borings and monitoring wells were completed in the following locations:

• AOC-1: Soil borings SB-1 through SB-10 were advanced throughout the area of the former High Street Mobil on the 112-122 High Street parcel. In particular, soil borings were advanced at the approximate locations of former USTs and dispensers identified during the Phase I ESA. Monitoring well MW-1 was installed at the SB-4 location, within the former UST and dispenser area.

• AOC-2: Two soil borings, identified as SB-11 and SB-17, were advanced in the area of the former steam laundry facility located at 339-343 Church Street. SB-11 was advanced in a presumed downgradient location of a possible UST identified during a GPR survey. SB-17 was advanced approximately in the center of the former steam laundry building.

• AOC-3: Five soil borings, identified as SB-12 through SB-16, were advanced in the area of the former auto repair/sales and machine shop building. SB-12 was advanced adjacent to a possible UST that was identified during the GPR survey.

SB-13 and SB-14 were advanced within and adjacent to a possible former dispenser pad that was identified during the GPR survey. SB-16 was advanced approximately in the center of the former building. Monitoring well MW-2 was installed at the SB-15 location, which was presumed to be downgradient of the possible UST and possible former dispenser.

• AOC-4: Nine soil borings, identified as SB-18 through SB-26, were advanced within the approximate location of the former Gadell’s Repair and Body Shop building formerly located at 98-100 High Street. Monitoring well MW-3 was installed at the SB-26 location, within AOC-4 and downgradient of AOC-1 and later to be identified as AOC 9 activities.

• AOC-5: Two soil borings, identified as SB-38 and SB-39, were advanced within the approximate location of the former Hertz Rent A Car, dress factory, and printing operation building located at 154-164 Allyn Street.

• AOC-6: Six soil borings, identified as SB-32 through SB-37, were advanced throughout the former clothing factory, Gengras Motor Cars, and Universal Auto Company formerly located at the 128-150 Allyn Street parcel. Monitoring well MW- 4 was installed at the SB-27 location, within AOC-6 and downgradient of AOCs 1, 2, 4, and, what was later identified as AOC 9, activities.

• AOC-7: Four soil borings identified as SB-28, 29, 30, and 31, were advanced in the vicinity of the battery station, sheet metal works, and woodworking building formerly located at the 120-124 Allyn Street parcel. Three possible USTs and one area of interest were identified in this location during the GPR survey. Soil borings were advanced in a presumed downgradient location of each potential tank /

Phase II / III Site Investigation 19 1800389 anomaly location. Monitoring well MW-5 was installed at the SB-28 location to collect area background groundwater information.

• AOC-8: Thirty-nine soil borings were advanced throughout the entire Site.

• AOC-9: Was not investigated during the initial Phase II SI activities.

Soil borings were advanced to depths ranging from 5 to 15 feet bgs. The completion depth of each boring was determined based on the likely depth of impact according to the CSM developed for the Site.

The five groundwater monitoring wells were set to a depth between 13 and 18 feet bgs.

Monitoring wells, MW-1, MW-2, MW-3, and MW-5 were constructed with 10 feet of 2-inch diameter, 0.010-inch slotted, schedule 40 polyvinyl chloride (PVC) well screens with an appropriate length of 2-inch diameter solid PVC riser pipe. Monitoring well MW-4 was constructed with 15 feet of 2-inch diameter, 0.010-inch slot, scheduled 40 PVC with an appropriate length of 2-inch diameter riser pipe. A #1 grain size morie sand pack was installed in the annular space between the well screens and the borehole sidewalls to a depth of approximately one foot above the top of the well screens. An approximately 1 to 2.5-foot thick bentonite seal was installed above the sand pack in monitoring wells MW- 3, MW-4, and MW-5. The remainder of the borehole annular space was backfilled with drill cuttings and sand. Monitoring wells MW-1 and MW-2 have no bentonite seal due to formation collapse and soil bridging. The monitoring wells were completed with flush mount covers set in a concrete surface seal.

The location of the soil borings and groundwater monitoring wells are depicted on the Site Investigation Plan (SI-01) included in Appendix B. Boring logs documenting subsurface conditions and well completion diagrams are included in Appendix A.

Phase II / III SI

BL Companies mobilized an HML-42 excavator operated by ACV Enviro on the nights of January 5, January 6, and January 7, 2019 to excavate test pits. A total of 11 test pits were completed in areas identified during the GPR survey to have the potential to contain USTs and/or anomalies and/or unknown objects. Test pits, identified as TP-1 through TP-11, were advanced to depths ranging from 6 to 10 feet bgs.

BL Companies mobilized a track-mounted Geoprobe 7822DT drill rig operated by Cummins Envirotech, Inc. (CEI) on March 11, 12, and 13, 2019, to advance soil borings and install groundwater monitoring wells at the Site. A total of 35 additional soil borings, identified as SB-101 through SB-135, and three groundwater monitoring wells, identified as MW-101 through MW-103, were installed at the Site. Soil borings, monitoring wells, and test pits were completed in the following locations:

• AOC-1: Soil borings SB-102 through SB-107 were advanced throughout the area of the former High Street Mobil at 112-122 High Street. In particular, soil borings

Phase II / III Site Investigation 20 1800389 were advanced in locations to delineate releases detected during the initial Phase II SI activates at borings SB-1, SB-4, and SB-9, and to further evaluate the…