FINAL WORK PLAN AMENDMENT NO. 7, PHASE 3 REMEDIAL ...At the request of the U.S. Environmental Protection Agency (EPA) Region I, NUS Corporation will complete Phase 3 of the Remedial

3 . 7 3

SDMS DocID 444410

W91133F

FINAL WORK PLAN AMENDMENT NO. 7 [Site^ . ^^^

Other:

PHASE 3

REMEDIAL INVESTIGATION/FEASIBILITY STUDY

SOLVENTS RECOVERY SERVICE

OF NEW ENGLAND, INC. SITE

SOUTHINGTON, CONNECTICUT

NUS Corporation

EPA Work Assignment No. 01-1 LOS

Contract No. 68-W8-0117

NUS Project No. 0217

April 1992

NUS CDRPORATiaN

i

W91133F

FINAL

WORK PLAN AMENDMENT NO.7

PHASE 3

REMEDIAL INVESTIGATION/FEASIBILITY STUDY

SOLVENTS RECOVERY SERVICE OF NEW ENGLAND, INC. SITE


NUS Corporation

EPA Work Assignment No. 01-1L08

EPA Contract No. 68-W8-0117

NUS Project No. 0217

April 1992

Llyang^Htt^' George

TABLE OF CONTENTS

FINAL WORK PLAN AMENDMENT NO. 7

PHASE 3 RI/F8

SOLVENTS RECOVERY SERVICE OF NEW ENOLAND, INC. SITE

SECTION PAGE

1.0 INTRODDCTION 1-1

2.0 SUMMARY OF EXISTING DATA 2-1

2.1 Study Area Description 2-1

2.1.1 Location 2-1

2.1.2 Climate 2-5

2.1.3 Environmental Setting and Population 2-6

2.2 Site History and Potential Contaminant Sources 2-7

2.2.1 SRSNE History 2-7

2.2.2 Potential Source Areas at the SRSNE 2-9

Operations Area

2.2.3 Potential Contaminant Areas 2-9

Beyond the SRSNE Operations Area

2.2.3.1 Former Cianci Property 2-9

2.2.3.2 Queen Street Diner 2-10

2.2.3.3 Other Alleged Disposal Areas 2-10

2.3 Site Characterization 2-11

2.3.1

2.3.2

2.3.3

2.3.4

Surface Water Drainage and Preliminary 2-11

Wetland Characterization

Geologic Characterization 2-12

2.3.2.1 Surficial Geology 2-12

2.3.2.2 Bedrock Geology 2-13

Study Area Hydrogeology 2-14

2.3.3.1 Horizontal Flow 2-14

2.3.3.2 Vertical Flow 2-15

2.3.3.3 Hydraulic Conductivity and 2-15

Velocity

Chemical Characterization 2-16

2.3.4.1 Soils 2-16

2.3.4.2 Groundwater 2-17

2.3.4.3 Surface Water and Sediments 2-20

2.3.4.4 Air 2-21

3.0 SCOPE OF THE PHASE 3 RI/FS 3-1

3.1 Data Requirements 3-1

3.1.1

3.1.2

3.1.3

3.1.4

3.1.5

Soils 3-1

Geology and Hydrogeology 3-2

Surface Water and Sediments 3-3

Air 3-3

Wetlands 3-3

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TABLE OF CONTENTS (Continued)


PHASE 3 RI/FS


SECTION PAGE

3.2 Preliminary Identification of ARARs 3-4

3.3 Preliminary Scoping of Remedial Action 3-6

Objectives and General Response Actions

3.3.1 Preliminary Identification of Remedial 3-6

Action Objectives

3.3.2 Preliminary Identification of General 3-18

Response Actions

3.4 Preliminary Risk Assessment 3-24

3.5 Objectives and Scoping of the Phase 3 RI/FS 3-25

3.6 Data Quality Objectives 3-25

3.6.1 DQO Levels 3-26

3.6.2 Use of Data 3-27

4.0 SCOPE OF THE PHASE 3 REMEDIAL INVESTIGATION 4-1

4.1 Task 0130 - Project Planning 4-1

4.1.1 Work Plan and Cost Estimate Preparation 4-1

4.1.2 Sampling and Analysis Plan 4-2

4.2 Task 0230 - Community Relations 4-3

4.3 Task 0330 - Field Investigation 4-4

4.3.1 Subtask 0331-Surficial Soils Sampling 4-4

4.3.2 Subtask 0332-Surface Water and Sediment 4-5

Sampling

4.3.3 Subtask 0333-Air Emissions Evaluation 4-6

4.3.4 Subtask 0334-Wetlands Evaluation 4-6

4.3.4.1 Wetlands Delineation 4-6

4.3.4.2 Flora and Fauna Survey 4-8

4.3.7 Subtask 0335-Groundwater Sampling 4-9

4.3.8 Subtask 0336-Topographic Surveying 4-9

4.4 Task 0340 - Geologic and Hydrogeologic 4-12

Investigations

4.4.1 Subtask 0341-Seismic Refraction Survey 4-14

4.4.2 Subtask 0342-Monitoring Wells and 4-15

Piezometer Installation

4.4.3 Subtask 0343-Light Non-Aqueous Phase 4-21

Liquid (LNAPL) Investigation

4.4.4 Subtask 0344 - Subsurface Soil Sampling 4-21

4.4.5 Subtask 0345-Long Term Groundwater 4-22

Monitoring

4.4.6 Subtask 0346 - Stream and Seepage 4-24

Gauging

4.4.7 Subtask 0347 - Evaluation of 4-24

Residential Well Logs

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PHASE 3 RI/FS


SECTION PAGE

4.5 Control and Disposal of Investigation Derived 4-25

Wates (IDW)

4.6 Task 0430-Sample Analysis and Data Validation 4-26

4.7 Task 0530 - Data Evaluation 4-26

4.8 Task 0600 - Risk Assessment 4-27

4.8.1 Data Evaluation/Hazard Identification 4-27

4.8.2 Exposure Assessment 4-28

4.8.3 Toxicity Assessment (Dose-Response 4-29

Assessment)

4.8.4 Risk Characterization 4-29

4.8.5 Ecological Risk Assessment 4-31

4.8.6 Identification of Remedial Response 4-34

Objectives and Target Levels

4.9 Task 0800 - Remedial Investigation (RI) Report 4-34

5.0 SCOPE OF THE FEASIBILITY STUDY 5-1

5.1 Task 0900 - Remedial Alternatives Screening 5-2

5.1.1 Development of Remedial Action 5-2

Objectives and General Response Actions

5.1.2 Identification and Screening of 5-3

Applicable Remedial Technologies and

Process Options

5.1.3 Development of Alternatives 5-3

5.1.4 Remedial Alternatives Screening 5-4

5.2 Task 1000 - Remedial Alternatives Evaluation 5-5

5.2.1 Overall Protection of Public Health 5-6

and the Environment

5.2.2 Compliance with ARARs 5-7

5.2.3 Long-term Effectiveness and Permanence 5-7

5.2.4 Reduction in Mobility, Toxicity, 5-7

or Volume

5.2.5 Short-term Effectiveness 5-8

5.2.6 Implementability 5-8

5.2.7 Cost 5-9

5.3 Task 1100 - Feasibility Study (FS) Report 5-10

5.4 Task 1200 - Post-RI/FS Support 5-11

5.5 Task 1600 - Administrative Record 5-11

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PHASE 3 RI/FS


SECTION PAGE

6.0 PROJECT MANAGEMENT 6-1

6.1 Project Organization 6-1

6.2 Quality Assurance and Data Management 6-1

6.3 Project Schedule 6-1

6.4 Cost Estimate 6-1

7.0 EQUIPMENT AND SUPPLIES 7-1

GLOSSARY OF ACRONYMS

REFERENCES

APPENDIX A - PROPOSED ENVIRONMENTAL SAMPLING MEMORANDUM

TABLES

NUMBER PAGE

POTENTIAL CHEMICAL-SPECIFIC ARARs AND TBCs 3-7

3-2 POTENTIAL LOCATION-SPECIFIC ARARs AND TBCs 3-11

3-3 POTENTIAL ACTION-SPECIFIC ARARs AND TBCs 3-14

3-4 GENERAL RESPONSE ACTIONS AND POTENTIAL 3-19

REMEDIAL ALTERNATIVES/TECHNOLOGIES

3-5 DATA QUALITY LEVELS FOR ANALYSES 3-28

4-1 PROPOSED SAMPLING OF MONITORING WELLS 4-10

4-2 SUMMARY OF PROPOSED MONITORING WELLS AND PIEZOMETERS 4-16

4-3 SUMMARY OF WELL AND PIEZOMETER DRILLING QUANTITIES 4-17

3-1

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PHASE 3 RI/FS


FIGURES

NUMBER PAGE

2-1 SITE LOCATION 2-2 2-2 STUDY AREA MAP 2-3 2-3 CURRENT FEATURES AT THE SRSNE FACILITY 2-4 4-1 PROPOSED MONITORING WELL, PIEZOMETER Oversized

AND SEISMIC SURVEY LINE LOCATIONS Drawing 4-2 PROPOSED SUBSURFACE SOIL SAMPLING LOCATIONS 4-23 6-1 PROJECT ORGANIZATION 6-3 6-2 PROJECT SCHEDULE 6-4

W91133F

1.0 INTRODUCTION

At the request of the U.S. Environmental Protection Agency (EPA)

Region I, NUS Corporation will complete Phase 3 of the Remedial

Investigation (RI) and Feasibility Study (FS) for the Solvents

Recovery Service of New England, Inc. (SRSNE) site in Southington,

Connecticut. This Work Plan Amendment (No. 7) was developed based

on the EPA Statement of Work (dated September 26, 1991) and the

results of project meetings. The work is authorized under Work

Assignment Number 01-1L08.

Phase 1 of the RI/FS investigated the presence of contaminants in

the environmental media in portions of the study area surrounding

the SRSNE Operations Area (the Cianci and Town well field

properties) . The results were used to develop and implement Phase

2, which investigated the nature and extent of contamination within

the SRSNE Operations Area and contaminant migration pathways and

transport mechanisms. All field investigation activities for

Phases 1 and 2 have been completed. Phase 3 will consist of the

completion of the field investigation tasks, preparation of the RI

report and the Risk Assessment, performance of the Feasibility

Study, and preparation of the FS report. In addition, as requested

in the EPA SOW, NUS will provide additional Community Relations

Support, provide post-RI/FS Support, and compile the Administrative

Record.

This Work Plan Amendment presents the technical scope of work and

schedule for conducting Phase 3 field activities, completing

engineering evaluations, and preparing reports for the SRSNE site.

The overall objective of the RI/FS is to develop a range of

remedial alternatives that addresses the environmental

contamination present at the site. To achieve this objective, the

RI/FS must:

1. assess the nature and distribution of contaminants in

groundwater, soils, surface water, sediments, and air

2. assess the fate and transport of these contaminants

3. evaluate through a risk assessment the potential threats

to human health and the environment posed by site

contamination

4. develop and evaluate a range of remedial alternatives

that address the site contamination

W91133F 1-1

The SRSNE RI/FS will be performed consistent with the requirements

of the following: the Comprehensive Environmental Response,

Compensation, and Liability Act (CERCLA) of 1980, as amended by the

Superfund Amendments and Reauthorization Act (SARA) of 1986, the

National Contingency Plan (NCP), and the EPA SOW (dated September

26, 1991).

This Work Plan Amendment contains seven sections: the Introduction

is presented in Section 1.0; Section 2.0 summarizes the existing

site data and the environmental contamination problem as it is

understood to date; Section 3.0 presents the results of scoping

activities including an initial identification of applicable or

relevant and appropriate requirements (ARARs), an identification of

potential remedial action objectives and general response actions,

and an identification of data gaps; Sections 4.0 and 5,0 present

detailed task descriptions for the RI and FS, respectively; Section

6.0 presents a proposed project management approach and projected

schedule for the performance of the RI/FS; and Section 7.0

identifies the equipment and consumable supplies necessary to

perform the activities identified in this Work Plan Amendment.

W91133F 1-2

2.0 SUMMARY OF EXISTING DATA

«r 2.1 Study Area Description

2.1.1 Location

The Solvents Recovery Service of New England (SRSNE) National

Priorities List (NPL) Superfund site is located in the Town of

Southington, Connecticut, in Hartford County, approximately 10

• miles southwest of Hartford. Figure 2-1 shows the general location

of the SRSNE, Inc. facility (Operations Area) with respect to the

Town of Southington and its environs. Figure 2-2 shows the site

« study area included in the scope of this Remedial

Investigative/Feasibility Study (RI/FS). The study area consists

of the SRSNE facility, the adjoining property to the east, known as

-p the former Cianci property, the Town of Southington well field, and

the lot formerly occupied by the Queen Street Diner on the eastern

side of the Quinnipiac River. The location of Southington

Production Wells Nos. 4 and 6, the contamination of which prompted

• the listing of the site on the NPL are also depicted on Figure 2-2.

SRSNE Operations Area

The SRSNE facility (Operations Area) consists of the grounds and

structures within the approximately 2.5 acre, fenced perimeter

where day-to-day drum storage and fuel blending operations were

**••" conducted from 1957 to March, 1991. The Operations Area sits on a

3.7 acre lot, owned by SRSNE, and includes the access road which

connects the facility to Lazy Lane. The facility is bordered on

•• the east by the Conrail right-of-way and the former Cianci

property. The Operations Area is located at the bottom of the

excavated portion of the hill situated on its western perimeter. A

9 detailed plan map of the Operations Area is depicted in Figure 2-3.

Former Cianci Property

** The former Cianci Property, an undeveloped 10 acre lot, is located

immediately east of the Operations Area. It was occupied by the

Cianci Construction Company from 1969 through June 1988. The lot

«i was used for the storage of construction equipment and as a truck-

washing station.

0 The property was sold to SRSNE in June 1988. The property extends

south from Lazy Lane approximately 1000 feet to the Town well field

property. The well field is bounded to the east by the Quinnipiac

River.

W91133F 2-1

•".•••-'•• ^ U H < m i Dvpaolo D«D«

' . I'i . K;iCton lich

' ^ v . ;•:! y r # K ^ ' i

SCALE 1000 1000 2000 3000 4000 WOO 6000 7000 f l V

SOURCE: US GEOLOGICAL SURVEY 7.5 MINUTE SERIES TOPOGRAPHIC MAPS. CONNECnCUT QUADRANGLES

(SOUTHINGTON, 1968 PHOTOREVISED 1984; MERIDEN, 1967,PR 1984; NEW BRITAIN, 1966, PR 1984; BRISTOL, 1966, PT 1984)

FIGURE 2 - 1 CONNECTICUT LOCATION MAP



W91133F 2-2

FIGURE 2-2 STUDY AREA MAP

SRSNE, INC. SITE AND TOWN PRODUCTION WELLS SOUTHINGTON, CONNECTICUT

W91133F 2-3

ALAl i 02 \ l \ A \ i l a , 91 M.]J

LECtNQ

Q EXTRACTION 1NEU

- » » - » - CHAIN UNK FENCE

f » - 1 RAH ROAD IHACKS

^ UONI TORINO WELL

60 130

SCALE M FEH FIGURE 2 - 3

CURRENT FEATU RESAIJHE

SOLVENTS RECOVERY SERVICE OF NEW ENGUND, INC. FACILITY

( '

' ' t s t t i f f

Town of Southington Well Field

'•^ The Town of Southington well field property consists of I approximately 28.2 acres of undeveloped land situated due south of

the former Cianci property. The Town Production Wells Nos. 4 and

6 are located approximately 2,000 and 1,400 feet south of the

former Cianci property, respectively. The Quinnipiac River flows

southward along the eastern edge of the former Cianci property and

a portion of the Town well field property. The river divides

Production Well 6 to the north of the river, and Production Well 4

' to the south. Wells 4 and 6 have not been used for water supply

since 1979 (NUS, 1989).

, In the late 1970s, Southington Town Production Wells Nos. 4 and 6,

both located less than a half mile form the SRSNE facility (see

Figure 2-1), were shut down because of solvent contamination.

Environmental officials contended that SRSNE caused the

* contamination in Well No. 6 and contributed to the pollution in

Well No. 4. In 1979, EPA filed suit against SRSNE under the

Resource Conservation and Recovery Act (RCRA) for contaminating

• Production Wells Nos. 4 and 6, and under the Clean Water Act for

the unpermitted discharge of pollutants into the Quinnipiac River.

The Southington Board of Water Commissioners and the Connecticut

, Fund for the Environment later joined EPA in that action. The 1979

suit was amended in 1982 to include claims under the 1980 Superfund

law. Before the case came to trial, an agreement, resulting in a

consent decree, was reached in 1983. The consent decree required

^K^ SRSNE to make improvements to its solvents handling procedures, to

install an on-site groundwater recovery and treatment system, and

to construct an off-site interception system to prevent

I contaminated groundwater from moving beyond the facility

boundaries. Because of this threat to public health and the

environment, EPA placed the SRSNE site on the National Priorities

, List in September 1983, making it eligible for federal assistance

for study and cleanup.

2.1.2 Climate

The Town of Southington, Connecticut, is located in a temperate

climate characterized by large daily and annual variations in

I temperature. Temperatures range from an average daily high of 34

degrees F in January to an average daily high of 85 degrees F in

July. The 30-year normal mean annual temperature is 50 degrees F.

The total annual record (30-year) mean precipitation in Southington

is 44.39 inches. During 1990, the highest monthly precipitation

was in October (9.61 inches) and the lowest in March (2.12 inches).

t i 4 l /

W91133F 2 - 5

2.1.3 Environnental Setting and Population

The SRSNE Study area vicinity includes a mixture of residential

dwellings, commercial and light industrial operations, and some

agricultural use. Most of the commercial/light industrial areas

are located along Route 10 (Queen Street), east of and parallel to

the Quinnipiac River Valley. Residential areas are primarily in

the upland areas east and west of the river valley and in the

center of Southington, just south of the study area.

Elevations in the site study area range from 150 feet above Mean

Sea Level (MSL) at the Quinnipiac River to 320 feet MSL in the

hilltops. Most of the study area lies in the Quinnipiac River

Valley, characterized by open grassy fields and some wetlands. The

surrounding upland areas are dominated by oak forests and

agricultural land.

East of the Studv Area

Due east of the site study area is the Quinnipiac River and Route

10 (Queen Street). A number of commercial operations including

auto body and repair shops, gasoline stations, stores, and

restaurants are located on Route 10. In general. Route 10 serves

as a major thoroughfare through the Town of Southington.

Residential dwellings are situated uphill, east of Queen Street.

North of the Study Area

Immediately north of the SRSNE Operations Area along the south side

of Lazy Lane is an auto body shop. North of Lazy Lane are tracts

of undeveloped land and a pond. One monitoring well (TW-12) is

located in this area. One private residence is situated across

from the former Cianci property.

West of the Study Area

Immediately uphill and west of the SRSNE Operations Area is the

Stanley Yorski property which has a house and several tracts of

land used for farming. Only private residences are situated west

of the Yorski property. A number of private residences are located

to the southwest of the study area in the vicinity of Curtiss

Street and in the upland areas.

South of the Study Area

A few small commercial operations exist in the immediate vicinity

of Production Well No. 4 along Curtiss Street.

M,

«l̂

W91133F 2-6

l»

Population

According to the 1980 U.S. Census, the population of Southington

was 36,879 persons. The July 1, 1986, population was estimated at

39,050.

2.2 Site Hiatorv and Potential coiitŵ iPTtnt Sources

2.2.1 SRSNE History

In 1979, EPA filed suit against SRSNE, Inc. charging it with the

contaminating Town Production Wells 4 and 6. Groundwater

contamination was documented at the SRSNE Operations Area, the

former Cianci property (now owned by SRSNE, Inc.), and Town

Productions Wells 4 and 6. The EPA, the Connecticut Fund for the

Environment, and the Board of Water Commissions for the Town of

Southington entered into a Consent Decree (CD) with SRSNE, Inc. in

December 1982. The major provisions of the CD required SRSNE, Inc.

to construct and operate on-site and off-site shallow groundwater

recovery systems, facility improvements, and increased pollution

prevention measures. The SRSNE site was proposed for listing on

the National Priorities List (NPL) in December 1982 and placed on

the final NPL list on September 1, 1983.

SRSNE began operations in Southington in 1955, receiving spent

industrial solvents and distilling for reuse or blending them for

use as a hazardous fuel product. From 1957 through approximately

1967, the non-recoverable fractions (consisting largely of still

bottom sludges) were disposed of in two unlined lagoons located

south of the SRSNE process building. Storm water runoff and

overflow from the primary lagoon were reported to be routed to the

southeast to a second lagoon (E & E, Inc., 1981). Use of the

lagoons for sludge disposal was discontinued in 1967 when they were

drained and covered with fill. Neither the quantity of sludge

disposed in the lagoons nor the amount removed could be determined.

After the lagoons were closed, wastes were incinerated in an open

pit or disposed of off-site. In the early to mid-1970s, the State

of Connecticut ordered the practice of incineration discontinued.

Beginning in the 1980s, waste solvents were no longer distilled at

the facility. The spent solvents, in tank trucks or drums, were

pumped through a filter, underwent a solids dispersal process, and

were then blended with fuel oil to increase the BTU content and

produce a hazardous waste fuel. The fuel was sold to companies for

firing cement kilns.

In addition to these contaminant source areas, past operating

practices may have contributed to contamination on the SRSNE and

surrounding properties. Such practices included the handling of

drums, the loading and unloading of tank trxicks, and the transfer

of spent solvents to and from the storage tanks before the facility

was paved or had spill containment barriers.

./ ' ' W91133F 2-7

Early in 1991, the State of Connecticut sought a temporary

injunction against SRSNE for its failure to meet the terms of its

existing RCRA permit. When the temporary injunction was granted,

SRSNE was given up to one year to meet specific legal requirements

by specified dates or face permanent closure. One of these

specific requirements was that SRSNE obtain adequate liability

insurance by May 28, 1991, for sudden accidental occurrences. As

of May 29, 1991, SRSNE confirmed to the Attorney General for the

State of Connecticut that it had not been able to obtain this

insurance. SRSNE, therefore, was legally obligated to permanently

close its facility.

On-site Interceptor System

One requirement of the 1982 Consent Decree was that SRSNE install

a system of interceptor wells to prevent further contaminant

migration from the Operations Area into the Town well field

property. The On-site Interceptor System installed by SRSNE, Inc.

in 1985 consists of 25 extraction wells connected to five pumps.

The On-site System, which began operating in January 1986, runs

along the eastern perimeter of the facility (see Figure 2-3). The

captured groundwater is pumped to the cooling tower and sprayed

into a countercurrent of air. Volatile organic compounds (VOCs)

are stripped from the groundwater and vented to the ambient air

without benefit of air pollution control devices (YWC, Inc., 1983).

Treated groundwater is discharged to a subsurface conduit connected

to a drainage ditch along the eastern perimeter of the facility

(just outside the fence). The effluent travels a short distance

before entering a culvert leading to the Quinnipiac River. Because

of operational problems and periodic system failure, SRSNE upgraded

the On-site Interceptor System in January 1990 by adding three

larger-diameter extraction wells. The system now operates on an

intermittent basis and is only activated when groundwater level

reaches a designated elevation.

At the request of EPA, NUS performed a brief technical evaluation

of the On-site Interceptor System in 1991. NUS determined that the

interceptor system is drawing groundwater from the fractured upper

bedrock rather than the overburden, and that contaminated

groundwater in the overburden is not effectively captured by the

On-site Interceptor System (NUS, 1991).

The discharge to the Quinnipiac River from the cooling tower is

permitted under Connecticut National Pollution Discharge

Elimination System (NPDES) program. A NPDES permit was issued in

December 1985 by the CT DEP (CT DEP, 1985) which allowed treated

groundwater to be discharged to the Quinnipiac River. As part of

the NPDES discharge reporting requirements, SRSNE monitors bi

weekly for the presence of pollutants in the effluent stream from

the cooling tower discharge. These pollutants include: trans 1,2dichloroethene; isopropyl alcohol; methylene chloride;

tetrachloroethene; acetone; butyl acetate; methyl ethyl ketone;

W91133F 2-8

methyl isobutyl ketone; phenol; 4-nitrophenol; 2,4-dimethylphenol;

isophrone; and barivim (CT DEP, 1985) .

Off-Site Interceptor System

The Off-Site Interceptor System was installed in the summer of

1986. It is parallel to and approximately 200 feet south of the

former Cianci property boundary in the Town well field property, as

shown in Figure 2-2. The system consists of extraction wells which

would intercept and capture contaminated groundwater migrating

southward toward the Town Production Wells. Since SRSNE has never

been issued an NPDES permit for this discharge, this off-site

system has never been brought on-line (YWC, 1983, 1984, 1986).

2.2.2 Potential contaainant Source Areas at the SRSNE Operations Area

The SRSNE Operations Area is currently inactive. The Operations Area is bounded by a fence which encloses the modular office

building, the operations building, the process area, the tank farm,

the drum storage area, the truck loading area, and access to the

On-site Interceptor System.

The two former unlined lagoons where distillation bottom sludges

were disposed, the former open pit incinerator, the tank farm

(consisting of a number of fuel and waste solvent storage vessels),

the operations building, the outdoor processing area, and the

leaching field are all potential contaminant sources. Based on the

analytical results of Phases 1 and 2 sampling activities,

contaminated groundwater and soils have been identified throughout

the Operations Area. During Phase 2, a geophysical survey study

identified a subsurface anomaly to the south of the operations

building which may represent the presence of a buried structure.

2.2.3 Potential Contaminated Areas Beyond the SRSNE Operations

Area

2.2.3.1 Former Cianci Property

Previous investigations by other EPA contractors have identified

the presence of VOCs in groundwater at the former Cianci property;

the contamination was attributed to the migration of contaminants

from the SRSNE Operations Area (Warzyn, 1979; E & E, 1981).

Analytical results of groundwater samples taken by NUS also

indicate that the presence of VOC contaminants in both the

overburden and bedrock aquifers is the result of contaminant

migration.

However, there are a number of potential causes for contamination

on the former Cianci property. Several individuals have alleged

that sludge was spilled as SRSNE trucks drove over the railroad

tracks at Lazy Lane enroute to off-site waste disposal locations.

W91133F 2-9

The spillage may have resulted in some contamination at the former

Cianci property. Large pools of liquid have been observed and

photographed on the former Cianci property; there have also been

reports of filling or dumping activities by SRSNE on the Cianci

property (E&E, 1980).

According to aerial photograph interpretations, the southern

portion of the Cianci property had undergone earth moving and

filling activities sometime after 1970 and prior to 1980.

Previously existing drainage pathways visible in these photographs

(1970 and earlier) and probable wetland areas were no longer

evident after 1970. The interpretations also indicated surface

runoff from the SRSNE Operations Area to the Cianci property in the

1967 and 1975 photographs (EPA EPIC, 1988).

2.2.3.2 Oueen Street Diner

During 1978 the CT DEP was informed that distillation bottoms and

sludges from the SRSNE, Inc. facility were disposed of behind the

former Queen Street Diner, adjacent to the Quinnipiac River. In

addition, gravel (contaminated with SRSNE sludges) from the

Mastrianni Gravel Pits (see Section 2.2.3.3) was used to fill a

portion of the flood plain behind the Queen Street Diner. The

diner, also owned by Tony Mastrianni, is no longer in operation.

This alleged disposal site has been included as part of the study

area of the RI/FS by EPA because it is contiguous to the study area

under investigation.

2.2.3.3 Other Alleged Disposal Areas

Additional disposal sites that may have been used by SRSNE, Inc.

were identified in the EPA FIT report (E & E, 1980) on the

contamination of Production Wells 4 and 6. These sites include the

Mastrianni Gravel Pits (along Flanders Road) and the Marek property

on Darling Street. In 1991, EPA provided the names and locations

of these sites to the CT DEP (EPA, 1991) . Site Assessment

investigation activities for these sites are being conducted by the

CT DEP and therefore will not be included in this RI/FS.

Based on aerial photographs, before 1970, the access road to the

SRSNE facility was located along the western boundary of the

Mickey's Garage property. Allegations have also been made that

sludges were discharged by tank trucks along this road as they left

the Operations Area (E & E, 1980).

W91133F 2-10

2.3 Site Characterization

2.3.1 Surface water Drainage and Preliminary Wetland Characterisation

The Quinnipiac River flows south through the study area, approximately 600 feet east of SRSNE. The river then turns west in

the southern portion of the study area between Production Wells 4

and 6. A tributary flows north from the location of the Northeast

Shaped Wire Company (formerly Ideal Forge) to meet the Quinnipiac

River near Production Well 4 (see Figure 2-2) . The river

subsequently turns south, and then east in the center of

Southington (not depicted in Figure 2-2).

An unlined drainage ditch parallel to the railroad tracks runs

along the eastern boundary of the SRSNE Operations Area. Ditch

drainage flow both north and south to a centrally located culvert

which conveys the surface water east beneath the railway to the

Quinnipiac River. Runoff from the north is derived principally

from a large wetland and two ponds north of Lazy Lane. Runoff from

the south comes from the SRSNE property and includes treated

effluent from the existing cooling tower/air-stripper.

The original runoff patterns across the former Cianci property

changed when the surface features were altered during the 1970s and

1980s. Historically, runoff from the SRSNE property was conveyed

under the railway through a short culvert which drained onto and

across the former Cianci property in a southeasterly direction

toward the Quinnipiac River. Between 1970 and 1975, a buried

culvert was installed east to west across the Cianci property, as

shown in aerial photos (ORD, EMSL, 1988). This culvert currently

carries discharge from the railway culvert east to the wetlands on

the west bank of the Quinnipiac River. Remnant wetlands remain

near the old surface drainage route in the southern and eastern

portions of the former Cianci property.

Extensive bordering wetlands which act as flood plains exist along

the Quinnipiac River's west bank in the vicinity of the Town well

field. Much of this area is comprised of cattail marsh and red

maple swamp. Similar wetlands were once thought to occupy the

former Cianci property. However, this area was altered extensively

as shown by aerial photographs of the area taken in 1975, 1980, and

1982 (EPA, EPIC, 1988).

^

W91133F 2-11

2.3.2 Geologic Characterization

2.3.2.1 Surficial Geology

The SRSNE study area is located within the Connecticut Valley

Lowland section of the New England physiographic province

(Fenneman, 1938) . Primary regional land forms were developed prior

to extensive glaciation during the Wisconsin stage, which scoured

and partially filled valleys with ground moraine (basal till) and

outwash deposits generally described as stratified glacial drift.

Basal till deposits mantle local hills and are somewhat continuous

in valleys except where scoured by later glacio-fluvial erosion

processes. The thickness of the unconsolidated units ranges from

about 20 feet at the SRSNE study area, increasing to 50 feet

towards the River.

Several boring programs have been conducted throughout the study

area by investigators on behalf of EPA, SRSNE, and the Town of

Southington. In general, these studies indicate the upper

unconsolidated overburden units are predominantly brown to reddish-

brown, fine to coarse sand with variable amounts of gravel. They

range from 0 to 40 feet thick. Discontinuous silty and clayey

lenses occur within the sandy units. Phase 2 field work has

generally supported the interpretations of earlier published

reports (Fritts, 1963 and Hanshaw, 1968) as summarized in Section

3 of the Phase 1 Technical Memorandum. These upper unconsolidated

units also include ice contact deposits, glacio-lacustrine, and

deltaic sequences. The basal unit of this sec[uence is represented

by a poorly sorted silty sand with abundant boulders and varying

amounts of clay. It is unclear whether this unit is glacio-fluvial

or an ablation till.

Investigations conducted by NUS during Phase 2 indicate all the

units described above exhibit similar hydrogeologic

characteristics. Therefore, these units have been grouped into one

hydrogeologic unit and are generally characterized by NUS as

stratified glacial drift.

Underlying the stratified drift is a basal till unit up to eight

feet thick. Mazzaferro (1978) described this unit as a continuous

mantle of dark red, clayey till of locally derived angular and

relatively unweathered arkose and diabase aggregate. Field

investigations conducted by NUS have confirmed this description and

the supposition that the basal till is widespread throughout the

study area vicinity. However, the NUS study did not confirm the

continuous presence of till throughout the study area. Windows, or

holes identified in the till mantle, are elongated and are

generally 200-300 feet long and 75 feet wide. These windows are

interpreted by NUS as post-glacial erosional features, resulting

from glacio-fluvial scouring during the ice retreat. They are

significant because they allow direct communication of potentially

contaminated groundwater from the upper stratified drift to the

W91133F 2-12

bedrock.

Several types of post-glacial surficial deposits also occur in the

area. Thin, discontinuous, eolian deposits are found throughout

the Lowland province. Freeze-thaw weathering causes extensive

intermixing of these and underlying units, often making the

deposits unidentifiable. Modern flood plain and swamp deposits are

also present along valley bottoms and are locally extensive within

the Quinnipiac River Valley. The thickness and full extent of

these deposits are not known at this time, but their presence is

not highly significant to this investigation.

2.3.2.2 Bedrock Geology

The study area is located within the lower member of a thick

sequence of New Haven Arkose which characterizes the region

(Fritts, 1963). The arkose is a poorly cemented, fine to medium

grained, brick red micaceous feldspathic sandstone. Also present

are interbeds of thinner, friable, and highly fractured, red to

brown siltstone and granule to pebble arkosic conglomerate (Fritts,

1963; Hanshaw, 1968). Thickness of beds ranges from a few inches

to several feet. Subsurface investigations and surficial outcrop

mapping by NUS and others have confirmed published descriptions of

this unit.

Structural information is limited in the locale because of the

paucity of outcrops. Seismic data (Weston Geophysical, 1990)

indicates the bedrock surface dips gradually from the SRSNE site to

the east and south, as the amount of unconsolidated overburden

increases. Regionally, the arkose unit strikes north to north-

northwest and dips gently eastward. However, bedding in a cluster

of outcrops south of the SRSNE facility strikes east-west and dips

gently both to the north and south (Fritts, 1963).

The nearest outcrop is located adjacent to the Caldor Mall parking

area on Queen Street. The outcrop mapped during Phase 2 indicates

that most bedding planes were also caused by erosion. The strike

of bedding plane orientations are therefore widely distributed;

however, a general preferential north-south bedding orientation has

been determined based on a large number of measurements.

Extensive weathering and fracturing of the arkose bedrock surface

was encountered in Phase 2 drilling operations. This fracturing is

intense to a depth of approximately 20 feet below the bedrock

surface. Four boreholes which were advanced in the bedrock during

Phase 2 investigations show that bedrock generally becomes less

fractured and more massive to a depth of 100 feet below the bedrock

surface.

A steeply dipping (approximately 65 - 80 degrees) series of

fractures was also noted in core samples recovered during the Phase

2 investigation. The strike of these fractures has not been

W91133F 2-13

determined. Some bedding planes and high angle fractures are open

and partially filled with clay and silt. These fractures may

represent preferential contaminant pathways.

The arkose has been intruded by a dark grey diabase. This unit is

locally referred to as a "traprock", and is defined as a fine

grained, dark colored, igneous intrusive rock. A diabase dike has

been mapped several miles both to the north and south of the study

area (Fritts, 1963). Fractures along the diabase/arkose contacts

may serve as preferential pathways, as noted in previous NUS

investigations. A diabase intrusive contact has been noted in

drill intercepts in the central portion of the Town well field.

The extent and significance of this occurrence is not known.

2.3.3 Study Area Hydrogeology

2.3.3.1 Horizontal Flow

The SRSNE study area is located in the Quinnipiac River Valley.

Glacial and alluvial deposits can have significant groundwater

yields where coarser grained materials are present. For example,

the two municipal gravel-packed wells which, in the past, supplied

water to the Town of Southington, each are capable of producing up

to 400 to 450 gallons of water per minute. Hydrogeologic units

capable of producing that quantity of water have not yet been

located in the study area.

Groundwater flow patterns in the study area can be interpreted from

monitoring well water level measurements collected during Phase 2

and other investigations conducted since 1980. Two aquifers have

been delineated in the Quinnipiac River Valley portion of the study

area: a water table aquifer in the saturated stratified drift and

a bedrock aquifer in the saturated, fractured upper 20 to 40 feet

of bedrock. The basal till unit described in Section 2.3.2.1

represents a semi-confining layer where it is present; however, the

windows through this unit allow direct communication of groundwater

between the two aquifers.

In the vicinity of the SRSNE facility and the former Cianci

property, groundwater generally flows east to southeast toward the

Quinnipiac River. The water table passes from bedrock into the

unconsolidated overburden in the vicinity of the SRSNE facility.

The saturated overburden, about 15 feet thick at the SRSNE

facility, generally increases to the east toward the Quinnipiac

River. At the former Cianci Property, the saturated overburden is

approximately 30 feet thick.

W91133F 2-14

II I *

2 . 3 . 3 . 2 V e r t i c a l Flow

Vertical groundwater gradients have been measured by NUS and

previous investigators. Results of these measurements have

indicated that both upward and downward groundwater gradients occur

in the Study Area. Warzyn (1980) measured vertical groundwater

gradients at monitoring well clusters TW-7A/TW-7B and TW-8A/TW-8B

in March 1980. This data indicated that the aquifer in the

vicinity of these wells was under slightly recharging conditions

(vertical downward groundwater movement) . Measurements made in May

1980 show slight recharge conditions in the vicinity of TW-7A/TW7B; however, discharging (vertical upward groundwater movement)

conditions were noted in the vicinity of TW-8A/TW-8B. Similar

variations were noted by NUS in 1990.

Artesian groundwater conditions have been observed in the SRSNE

Production Well located within the Operations Area. In addition,

private supply wells have also been known to free flow at the

ground surface in several residential lots on Lazy Lane (upslope

and upgradient) of the Operations Area. These artesian conditions

may be related to seasonal heavy rains and thawing/run-off from the

hillside to the west of the SRSNE Operations Area. The windows

through the till provide direct communication for groundwater flow

from one aquifer to another, possibly giving rise to the vertical

groundwater gradients.

2.3.3.3 Hydraulic Conductivitv and Groundwater Velocity

Hydraulic conductivity tests (variable head slug tests and packer

tests) were conducted by NUS as part of the Phase 2 investigation.

Slug tests, performed in the unconsolidated units, provided order

of magnitude estimates of hydraulic conductivity of an average of

all layers adjacent to the well screen. The unconsolidated unit

contains many thin layers of sand, silt, and clay, each of which

has a different hydraulic conductivity. The sand layers will have

higher conductivity values than the test results while the clays

will display lower values. The data indicate that the stratified

drift unit has a hydraulic conductivity in the range of 10'* to IC'

centimeters per second (cm/sec) . Although no testing was conducted

in the basal till unit, conductivities are estimated to be two to

three orders of magnitude lower, based on the composition and

relative density of the unit. Using the above data, the average

linear velocity of groundwater flow was calculated using Darcy's

Law. The velocities range from three to 30 feet/year through the

water table aquifer and represent averages of various layers.

Packer tests were performed to measure the hydraulic conductivity

of the bedrock fractures within the test sections which are capable

of transmitting water. However, the analytical solution assumes

that the water pumped into the test section is accepted through its

entire length and not just by a few thin fractures. This

assumption results in the reported bulk hydraulic conductivity

W91133F 2-15

being much lower, possibly by several orders of magnitude, than the

conductivity of individual fractures. Conductivities measured in

the bedrock aquifer during Phase 2 range from 10"* to 10"' cm/sec.

The calculated velocities range from three to 30 feet/year in the

bedrock aquifer and represent minimum values.

Because of the nature of the unconsolidated and bedrock units at

the study area, the measured values of hydraulic conductivity must

be used with care since they represent bulk values of all layers or

fractures tested within an unit. The data developed are useful for

comparing the relative hydraulic conductivities of individual

units. Since the calculated groundwater velocities represent

average or minimtim values (in the overburden or bedrock,

respectively), the actual velocities of individual layers or

fractures may be higher.

2.3.4 Chemical Characterization

Detailed discussions of the presence and distribution of organic

and inorganic contaminants are presented in the Technical

Memorandum for Phase 1 and the Draft Technical Memorandum for Phase

2 of the RI/FS. Summaries of those discussions are presented

below.

2.3.4.1 Soils

Surface Soils

Based on field screening data developed during the Phase

2 drilling program, the surficial soils in the former

Cianci property and the Town well field do not appear to

contain detectable concentrations of VOCs.

Mr. Sigmund Yorski, an abutter for over 30 years, alleged

that cooling tower emissions and past open burning by

SRSNE resulted in contaminants being deposited on his

property. As a result, he believed that one tract of his

land cannot be used for growing crops (NUS, 1990).

Past burning of still bottoms in the open-pit may have

resulted in aerial deposition of contaminants in the

study area.

Subsurface Soils

Available Phase 2 soils analytical data indicated the

presence of fuel components (benzene, toluene, ethyl

benzene, and xylenes [BTEX]) up to 5,970,000 M^/l) and

several VOCs within the Operations Area.

W91133F 2-16

Phase 2 data indicated VOCs presence throughout the

Operations Area including: 2-butanone; 1,2dichloroethene; 1,1,1-trichloroethane; trichloroethene;

tetrachloroethane; 4-methyl-2-pentanone; and styrene. A

number of semi-volatile organic compounds (SVOCs) were

noted along with PCBs (Aroclor 1016, 1248, 1254, and

1260).

Phase 2 data also indicated the presence of VOCs in the

former Cianci property at several orders of magnitude

lower than those found in the Operations Area. No

pesticides/PCBs and only one SVOC was detected in the

samples from the former Cianci property.

No VOCs, SVOCs, and pesticides/PCBs were detected in

samples from the Town well field.

Phase 2 findings confirm previous investigations which

also indicated the presence of a variety of organic

compounds, as well as PCBs and dioxin, in subsurface soil

samples obtained from the Operations Area (Weston 1988).

2.3.4.2 Groundwater

Two primary pathways have been identified for potential organic

contaminant transport. In the overburden, contaminants can migrate

through the hydraulically conductive layers (sands). The other

pathway consists of fractures in the top of bedrock. Phase 1 and

2 data indicate the following:

Overburden

During Phase 1 sampling, VOCs, SVOCs, and several heavy

metals were detected primarily in wells adjacent to and

downgradient of the SRSNE facility.

VOC contaminants in groundwater are migrating away from

the Operations Area towards the Quinnipiac River and Town

well field. The highest concentration of VOCs was

detected in Operations Area groundwater seunples.

At the Operations Area, VOCs and SVOCs in groundwater

were detected primarily near the former secondary lagoon

and the tank farm. The On-site Interceptor System may be

limiting dispersion of contaminants by inducing

groundwater flow in a limited channel.

PCBs were detected in groundwater samples collected from

the P-IA and B well cluster in the Operations Area. The

presence of numerous solvents and some surfactants may

have caused the PCBs to partition to the aqueous phase.

W91133F 2-17

Bedrock

Groundwater contaminants observed at the Operations Area

and at downgradient locations have been identified by

SRSNE in NPDES reports and in the list of chemicals the

facility typically handled.

Contaminated groundwater with elevated concentrations of

VOCs and SVOCs appears to flow east from the Operations

Area to the Quinnipiac River along a limited path.

VOCs and SVOCs were found only in the southern half of

the former Cianci property. Based on Phase 1 and Phase

2 data low levels of VOCs are present in the water table

aquifer of the Town well field.

Groundwater contamination from the water table aquifer

enters the shallow bedrock aquifer through the till

window present in the Operations Area. The vertical

gradients observed support this conclusion.

The presence of non-aqueous phase liquids (NAPLs) is

likely, based on the concentration of VOCs in groundwater

and field observations of boreholes in the Operations

Area. The dense NAPLs can migrate along the interface

between two geologic materials with significantly

different hydraulic conductivities or along the alluvium-

till boundary under gravity rather than with groundwater

flow. The dense NAPLs may also lodge in the bedrock

fractures and be a continuing source of contamination.

Field screening using a Photovac 10S50 GC indicated the

presence of VOCs throughout the study area. VOCs were

detected as far east as the Quinnipiac River (to within

50 feet), as far north as Lazy Lane including Mickey's

Garage, and as far south as the Connecticut Light and

Power high tension lines in the Town well field. VOCs

were not detected through field screening at MW-129, west

and upslope of the Operations Area.

VOCs were detected in monitoring wells south of Well No.

4 (south of Curtiss Street and the Quinnipiac River)

during Phase 1. Based on the mapped horizontal

overburden groundwater gradient, other potential sources

may be responsible for contaminants detected in these

monitoring wells.

Available data suggest that contaminants from the

Operations Area can migrate from the SRSNE facility

source areas laterally through the overburden, and

vertically and laterally through the bedrock fractures.

W91133F 2-18

VOC contaminants have been identified in all shallow

bedrock wells downgradient of the Operations Area

indicating that contaminant migration is pervasive in the

bedrock aquifer.

The shallow bedrock is more contaminated by VOCs than the

deep bedrock. Vertical gradients indicate the potential

for contaminant penetration to deeper fractures. The

presence of VOCs in both the shallow and deep bedrock

support this conclusion.

Contaminated groundwater at the Operations Area appears

to enter the shallow bedrock through a till window

adjacent to the tank farm and process area.

Contaminated groundwater can migrate a substantial

distance downgradient in the fractured bedrock until a

till window is reached. At some well locations where the

till is absent, groundwater in the shallow bedrock well

is more contaminated by VOCs than the corresponding

overburden well.

VOCs presence in cross-gradient wells north of the

Operations Area indicates that some mechanism is inducing

flow to those wells. The pumping of private (industrial,

commercial, or residential) water supply wells north of

the study area may cause the cross-gradient migration of

contaminants.

Bedrock wells immediately upgradient of the Operations

Area have low levels of VOC contamination. The presence

of VOCs may have occurred because of some other transport

mechanism such as diffusion.

A number of previously installed monitoring wells in the

study area were screened across multiple geologic units

and are therefore of limited use in identifying

contaminants or groundwater gradients in specific

geologic units. These wells may also allow communication

of contaminants from one unit to another.

Field screening detected VOCs in bedrock adjacent to Lazy

Lane, which is located hydraulically cross-gradient from

the SRSNE facility. The CT DEP also found VOCs in an

adjacent residential bedrock well.

W91133F 2-19

2.3.4.3 Surface Water and Sediments

Surface water and sediment sampling in the study area was performed

during Phase 1 to characterize the presence of contaminants and

assist in defining sxibsequent field investigation activities. The

status of contaminant presence includes the following:

VOCs were detected primarily in the surface water and

sediments of the drainage ditch which channels the

discharge from the cooling tower/air stripper to the

Quinnipiac River. The highest concentrations were

identified at this location.

One PCB compound (Aroclor 1254) was also found in the

surface water and sediment of the drainage ditch (SWl-4)

and the culvert (SWl-5). This indicates that PCBs are

being discharged in the cooling tower effluent. The

presence of a number of organic solvents in groundwater

may be causing the PCB to solubilize.

Semi-volatile organic compounds were found in the cooling

tower effluent which flows into the drainage ditch and

migrates to the Quinnipiac River.

A number of heavy metals were identified in the aqueous

and sediment samples of the drainage ditch and culvert.

Heavy metals including arsenic, chromium, cadmium,

cobalt, lead, and mercury are present in the sediment.

Cyanide was identified in the drainage ditch sediment.

• VOCs were identified in ponded water at the surface

runoff area southeast of the SRSNE facility. No semi-

volatile organic compounds, pesticides, or PCBs were

detected in the aqueous samples. A few semi-volatile

compounds were detected in sediment. Heavy metals were

identified in both the aqueous and sediment samples.

Toluene was the only VOC detected in the aqueous and

sediment samples from the Quinnipiac River. Only one

SVOC was detected in aqueous samples collected at two

river locations. A number of SVOCs were detected in the

river sediments; the downstream locations generally have

greater SVOC concentrations. At a multiple-depth

sediment sampling location, SVOC concentrations showed a

slight decrease with depth. Insufficient data exists to

draw general conclusions regarding contaminant presence

versus depth.

Lead was identified in the upstream and downstream

samples at comparable concentrations. Arsenic was

detected only in the most downstream location.

W91133F 2-20

2.3.4.4 Air

The Phase 1 air sampling study, performed when the facility was

still active in July, 1990, was conducted to qualitatively evaluate

ambient air conditions. The data was used to identify health and

safety measures for field investigation crews. The results of air

sampling indicate the following:

• VOCs are discharged to the ambient air through a cooling

tower/air stripper without any air pollution control

devices.

• Much of the Operations Area has been paved with asphalt

so that VOC emissions from contaminated surficial soils

are unlikely.

Analytical data were compared with Connecticut's Hazard

Limit Values (HLVs) for hazardous air pollutants; the

VOCs detected were generally several orders of magnitude

lower in concentration than the HLVs.

Generally, the number of compounds and the concentrations

detected were greatest in the prevailing downwind

direction (east, northeast, and south) of the SRSNE

facility. Because of variable wind directions occurring

during the air study, it is possible that all air

sampling locations may have been affected by VOC

emissions from the SRSNE facility.

True background concentrations of VOCs in the ambient air

are not known because of the limited niimber of sampling

locations, the preliminary nature of the investigation,

and variable wind directions.

W91133F 2-21

3.0 SCOPE OF THE PHASE 3 RI/FS

The scope of Phase 3 of the Remedial Investigation/Feasibility

Study was developed by conducting a preliminary risk assessment

(NUS, 1989), identifying the data requirements and a preliminary

set of ARARs, and performing a preliminary scoping of remedial

action objectives and general response actions. The evaluation of

these findings defined the Phase 3 objectives and focused the field

investigation activities.

3.1 Data Requirements

Field investigation activities conducted during Phases 1 and 2

generated data assessing the presence of contaminants in the

environmental media. As a result, a list of proposed data

requirements was developed and provided to EPA (NUS, September

1991). Following the scoping meeting of October 15, 1991, EPA

concurred with a number of these requirements. A brief summary of

the data necessary to further assess the nature and extent of

contaminants, perform the baseline risk assessment, and develop

remedial alternatives under the FS is presented in this Section.

3.1.1 soils

The subsurface soils within the Operations Area were sampled during

Phase 2 as part of the drilling program. Subsurface samples were

also collected from the former Cianci property and parts of the

Town well field. Additional data will be needed to address the

presence of soil contaminants and will be useful in the risk

assessment and evaluation of remedial alternatives. These include:

Surficial soil contaminants (other than VOCs) at the

former Cianci property

The presence of surficial soil contaminants (other than

VOCs) that may have been deposited by aerial transport at

the Town well field

Alleged soil contamination at the Yorski's property (west

of Operations Area)

Soil contamination at the (former) Queen Street Diner

Additional background (upgradient) samples for input into

the baseline risk assessment

The anomaly identified by the Phase 2 GPR survey

W91133F 3-1

3.1.2 Geology and Hydrogeology

Past investigations have characterized an extensive plume of VOCs

in groundwater in the overburden emanating from the SRSNE

Operations Area that is migrating east and southward. Natural flow

patterns appear to be directed to the river. Until 1979 southerly

migration may have been caused by the operation of the Town

Production Wells. Additional data will be required to better

define contaminant migration pathways and transport mechanisms.

Further characterization of the site geology and hydrogeology may

include the following:

Determining the quantity of water that enters the

Operations Area from the west (Yorski property) due to

groundwater flow and precipitation. This data would be

useful in evaluating source control and dewatering

measures.

Clarifying the presence of VOC contamination in a cross-

gradient shallow bedrock well (P-12A). Migration of

contaminants in bedrock fractures in a northerly

direction (north of Lazy Lane) has not been delineated.

Private or industrial wells north of the study area may

exist that influence groundwater flow in bedrock.

Collecting geologic and hydrogeologic data for portions

of the Town well field. Phase 2 activities extended to

approximately the location the CL & P power lines.

Additional data will be required to better define the

geologic and hydrogeologic conditions of the southern

portion of the study area.

Assessing the potential impact of contamination from the

SRSNE, Inc. facility on the east side of the Quinnipiac

River. It is uncertain whether the Quinnipiac River acts

as a hydrogeologic boundary. Phase 2 data suggest that

VOCs in the bedrock fractures migrate toward and under

the river.

Assessing groundwater that may discharge from the bedrock

fractures to a hypothesized pre-glacial river valley

located to the east of the present day Quinnipiac River.

If this valley exists, it could represent the eastern

most extent of contaminant migration and a pathway for

contaminant transport.

Evaluating seasonal variation in precipitation and water

levels. These variations coupled with the semi-confining

quality of the till may be the driving force for the

upward vertical groundwater flow observed to date. This

information may be useful for the FS and remedial design.

v..

W91133F 3-2

Collecting additional data to evaluate the potential for

contaminants to migrate from the study area bedrock

fractures towards the west and southwest where residences

with private wells are located.

3.1.3 Surface Water and Sediments

The Phase 1 analytical data compiled may be used to determine

whether the presence of organic compounds and inorganics in the

surface water and sediments pose a threat to human health and the

environment. Additional data requirements for Phase 3 include the

following:

Determining whether the detection limits of the CLP

Routine Analytical Services are sufficiently low to

identify exceedances of MCLs or AWQCs.

• Evaluating the presence of PCBs in the cooling tower

effluent discharge. It is unclear whether the PCBs are

transported with suspended materials or remain in

solution because of elevated solvent (VOCs)

concentrations and the presence of surfactants.

Defining the extent of VOCs, semi-volatile organics,

pesticides and PCB, and inorganics contamination

(laterally and vertically) in the drainage ditch and

culvert sediments.

Characterizing the extent and depths of contaminants

along the banks of and in the Quinnipiac River.

3.1.4 Air

The air sampling performed to date has been limited; its results

will be used only to specify health and safety requirements for the

field investigators. Since the CT DEP is proceeding with

installation of an air emissions control system, the only

additional air sampling activity required is to define background

concentrations for air contaminants to provide data for the

baseline risk assessment.

3.1.5 Wetlands

Wetlands exist in sizeable portions of the study area (primarily

the former Cianci property and parts of the Town well field).

Delineating wetland boundaries is necessary since their presence

may affect selection of remedial alternatives. Data requirements

for the wetlands are as follows:

W91133F 3-3

3.2

Confirming the classifications by the Town of Southington

of portions of the Cianci property and the well field as

wetlands. The results may affect the implementation of

remedial alternatives.

Delineating and mapping the wetlands in the study area.

• Sampling to delineate contaminant presence.

Identifying the flora and fauna found in the study area

and wetlands.

Preliminary Identification of Applicable or Relevant and

Appropriate Requirements

The National Contingency Plan requires the development of remedial

alternatives that are protective of human health and the

environment and attain the applicable or relevant and appropriate

requirements of other Federal and State environment laws.

An ARAR is defined as:

• Any standard, requirement, criterion, or limitation under

Federal environmental law

• Any promulgated standard, requirement, criterion, or

limitation under a state environmental or facility siting

law that is more stringent that the associated Federal

standard, requirement, criterion, or limitation

Applicable requirements are those Federal and state requirements

that would be legally applicable to the response action if that

action were not taken pursuant to Section 104 or 106 of CERCLA.

Relevant and appropriate requirements are those Federal or state

requirements that, while not applicable, are designed to apply to

problems sufficiently similar to those encountered at CERCLA sites

that their application is appropriate. Relevant and appropriate

requirements are intended to have same weight as applicable

requirements. EPA has also indicated that other criteria,

advisories, and guidelines be considered during the development of

remedial alternatives. Examples of such other criteria include the

EPA Drinking Water Health Advisories, Carcinogenic Potency Factors,

and Reference Doses. Collectively these criteria are designated as

To Be Considered (TBCs).

Section 121 of SARA requires that the remedy for a CERCLA site must

attain all ARARs unless one of the following conditions is

satisfied: (1) the remedial action is an interim measure where the

final remedy will attain the ARAR upon completion; (2) compliance

will result in greater risk to human health and the environment

than other options; (3) compliance is technically impracticable;

(4) an alternative remedial action will attain the equivalent of

W91133F 3-4

the ARAR; (5) for state requirements, the state has not

consistently applied the requirement in similar circumstances; or

(6) compliance with the ARAR will not provide a balance between

protecting human health, welfare, and the environment at the

facility with the availability of Fund money for response at other

facilities (Fund-balancing).

ARARs will be considered at four points during the RI/FS process:

(1) Field Investigation (Task 0330); (2) Pxiblic Health and

Environmental Assessment (Task 0600); (3) Remedial Alternatives

Screening (Task 0900); and (4) Remedial Alternatives Evaluation

(Task 1000).

ARARs fall into three broad categories, based on the manner in

which they are applied at a site. These categories are:

Chemical-specific ARARs are usually health- or risk-based

numerical values or methods which, when applied to site-

specific conditions, establish niomerical values for an

acceptable concentration of chemicals that may be found

in, or discharged to, the ambient environment.

Location-specific ARARs are restrictions placed on the

concentration of hazardous substances or the conduct of

activities solely because they occur in specific areas or

locations.

Action-specific ARARs are usually technology-or activity-

based requirements or limitations on actions taken with

respect to hazardous wastes. Examples of action-specific

ARARs include monitoring requirements, effluent discharge

limitations, hazardous waste manifest requirements, and

occupational health and safety requirements.

TBCs are non-promulgated, non-enforceable criteria, advisories, and

guidance issued by Federal or state government that are not legally

binding and do not have the status of potential ARARs, but are

considered in determining the necessary levels of cleanup for

protection of human health and the environment.

Under the Superfund Amendments and Reauthorization Act (SARA), the

substantive requirements of ARARs (and TBCs necessary to ensure a

remedy is protective) must be attained for hazardous substances,

pollutants, or contaminants remaining on site at the completion of

the remedial action, unless a waiver of an ARAR is justified. The

implementation of remedial actions must also comply with ARARs (and

TBCs, as appropriate) to protect human health and the environment.

W91133F 3-5

Tables 3-1, 3-2, and 3-3 present a preliminary summary of potential

Federal and state ARARs and TBCs (chemical-specific, location-

specific, and action-specific) for the SRSNE site. Summaries of

the requirements and their consideration in the RI/FS are provided

in the tables.

The potential Federal ARARs were identified through EPA documents

Guidance for Conducting Remedial Investigations and Feasibility

Studies Under CERCLA fl988) and CERCLA Compliance with Other Laws

Manual fl988). State ARARs were identified through a review of

Connecticut Regulations. State ARARs will be revised as necessary

pursuant to comments solicited from the Connecticut Department of

Environmental Protection.

3.3 Preliminary Scoping of Remedial Action Objectives and General Response Actions

Data developed during Phases 1 and 2 provide information on contaminants in the environmental media and potential receptors.

These data allow for the formulation of an initial set of remedial

action objectives and general response actions. The remedial

action objectives are developed based on the contaminants present,

media of interest, potential exposure pathways, and preliminary

remediation goals. General response actions for each medium of

interest define the actions that may be taken to address the

remedial action objectives. For each general response action

developed, a list of potential remedial technologies can be

developed that would achieve the desired goals.

Based on existing data. Section 121 of SARA and the current NCP,

several preliminary remedial action objectives and general response

actions have been identified; others will be identified during the

performance and following completion of RI site characterization

activities. As discussed in Section 2.3.3, both organic and

inorganic contaminants have been identified in the groundwater, the

surface water and sediments, and subsurface soils.

To achieve the remedial action objectives, a baseline human health

risk assessment based on current site conditions will be performed

to identify which contaminants and exposure scenarios pose threats

to human health and the environment. In addition, meeting the

requirements of the general response actions calls for attaining of

federal and state ARARs.

3.3.1 Preliminary Identification of Remedial Action Objectives

A list of preliminary remedial action objectives was developed

based on available site contamination data:

W91133F 3-6

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Contaminant Medium/Authori ty

GROUNDWATER Federal Requirements

i -J Federal Requirements

Federal Requirements

TABLE 3-1

POTENTIAL CHEMICAL-SPECIFIC ARARs AND TBCs

SOLVENTS RECOVERY SERVICE OF NEW ENGLAND, INC. SUPERFUND SITE


Requirement Requirement Synopsis Consideration in the RI/FS

SDWA - Maximum Contaminant MCLs have been promulgated for a number of When the risks to human health because of Levels(MCLs)(40CFR141 11- common organic and inorganic contaminants. consuming groundwater are assessed, 141 16) These levels regulate contaminant concentrations of contaminants of concern

concentrations in public drinking water supplies wi l l be compared to their MCLs. The SDWA MCLs are applicable to the distribution system of the public water system supplied by the well station and are relevant and appropriate to the aquifer.

SDWA Maximum Contaminant MCLGs are health-based limits and do not take Non-Zero MCLGs may be considered relevant Level Goals (MCLGs) (40 CFR 141) cost or feasibility into account As health goals, and appropriate when other human health

MCLGs are established at levels at which no threats at the site justify setting lower cleanup known or anticipated adverse effects on the levels. MCLGs may also be relevant and health of persons occur and which allow for an appropriate if multiple contaminants or adequate margin of safety. multiple exposure pathways require levels

that are more stringent than MCLs.

RCRA - Groundwater Protection The RCRA groundwater protection standard is The corrective action monitoring under RCRA Standard (40 CFR 264.94) established for groundwater monitoring of Subpart F may be relevant and appropriate.

RCRA-permitted treatment, storage, or disposal facilities. The standard is set at either an existing or proposed RCRA-MCL, background concentration, or an alternate concentration l imit protective of human health and the environment.

TABLE 3-1 H H POTENTIAL CHEMICAL-SPECIFIC ARARs AND TBCs

SOLVENTS RECOVERY SERVICE OF NEW ENGLAND, INC. SUPERFUND SITE • « 1 SOUTHINGTON, CONNECTICUT

PAGE TWO

Contaminant Requirement

Medium/Authority

GROUNDWATER (Continued)

State Requirements

I 09

State Requirements

State Requirements

Criteria, Advisories, and Guidance To Be Considered (TBC)

Connecticut Standards for Quality of Public Drinking Water

Connecticut Water Quality Standards (Section 22a-426) Subpart IV Groundwater

Action Levels (Connecticut General Statutes Section 22a471) and Public Health Code Regulations (Section I9-13-B102)

EPA Risk Reference Doses (RfDs)

Requirement Synopsis

Connecticut has adopted the SDWA MCLs to regulate concentrations of contaminants in public drinking water supplies. Connecticut standards are more stringent than SDWA MCLs for some compounds.

Connecticut has adopted the SDWA MCLs to regulate contaminants in certain groundwater

The Department of Health Services (DOHS) use these Regulations and Action Levels in determining the potability of drinking water supplies. An Action Level is defined by the DOHS as a level which can reasonably be expected to create an unacceptable risk of injury to the health or safety of persons using such groundwater as a public or private source of water for drinking.

Rf Ds are dose levels developed by EPA for noncarcinogenic effects.

Consideration in the RI/FS

State standards, where more stringent than Federal require-ments, are applicable to the distribution of water supplied by the production wells and are relevant and appropriate to the aquifer.

Discharges to surface water and groundwater must not degrade the designated quality of the water. Remedial actions may restore groundwater to a quality consistent w i th Clasi [ GA (private and public drinking water supply).

The Action Levels are applicable to the distribution of water supplied by the Production Wells, and are relevant and appropriate to the aquifer.

EPA Rf Ds were used to characterize risks due to exposure to contaminants in groundwater as well as other media.

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SOUTHINGTON. CONNECTICUT PAGE THREE

Contaminant Requirement

Medium/Authority

GROUNDWATER

Federal TBC

Federal TBC

Federal TBC VO


SURFACE WATER

State Requirements

(Cont inued)

EPA Carcinogen Assessment Group Potency Factors

EPA Health Advisories and Acceptable Intake Health Assessment Documents

EPA Groundwater Protection Strategy

CWA - Ambient Water Quality Criteria (AWQC) - Protection of Freshwater Aquatic Life, Human Health - Fish Consumption

Connecticut Water Quality Standards and Classification


EPA Carcinogenic Potency Factors are used to compute the individual incremental cancer risk resulting from exposure to carcinogens.

These are intended for use in a qualitative public health evaluation of remedial alternatives.

GPS provides classification and restoration goats of groundwater based on its vulnerability, use, and value.

AWQC are developed under the Clean Water Act (CWA) as guidelines from which states develop water quality standards. A more stringent AWQC for aquatic life may be found relevant and appropriate rather than an MCL, when protection of aquatic organisms is being condsidered at the site.

These standards provide criteria for classifying and maintaining the quality of groundwater and surface water.


These factors were used to assess health risks from carcinogens present at the site

If adequate data exist, these wi l l be used in assessing health risks from ingesting groundwater at the site.

This strategy is considered in conjunction wi th the Federal SDWA and Connecticut Water Quality Standards in establishing cleanup levels.

AWQCs may be used at the site to characterize risks to fresh water aquatic life. AWQC may also be considered in the risk assessment wi th regard to human ingestion of fish.

Chemicals released to surface water and groundwater must not degrade the designated quality of the water. These standards would be applicable to the Quinnipiac River.

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t J SOLVENTS RECOVERY SERVICE OF NEW ENGLAND, INC. SUPERFUND SITE

SOUTHINGTON, CONNECTICUT PAGE FOUR

Contaminant Medium/Authority

SOILS AND SEDIMENTS

Criteria, Advisories, and Guidance To Be Considered (Federal)

Federal TBC

AIR Federal Requirements

State Requirements

Criteria, Advisories, and Guidance To Be Considered (Federal)

Requirement

TSCA PCB Spill Clean-up Policy (40 CFR 761)

Sediment Quality Criteria

CAA- National Emissions Standards for Hazardous Air Pollutants (NESHAPS) (40 CFR 61), and National Ambient Air Quality Standards (NAAQS)

Connecticut Air Pollution Control Regulations (Connecticut General Statutes Section 22a174)

OSHA Threshold Limit Values (TLVs)

Requirement Synops is

This policy applies to recent PCB spills and establishes clean-up levels for three types of sites.

The health-based criteria also cover certain contaminants in sediment.

NAAQS have been developed for seven pollutants and pertain t o ambient concentrations.

The regulations l imit emissions that prevent or interfere w i th the attainment or maintenance of Connecticut Standards and NAAQS. They set standards ((hazard-limiting values, (HLVs)) for ambient air quality.

These standards were issued as consensus standards for controll ing air quality in indoor workplace environments.


Not applicable to CERCLA sites, but standards may be used as guidelines for soil cleanup at the SRSNE site if PCB contamination must be addressed.

SQC may be used to characterize risks to aquatic organisms because of contaminant concentrations in sediments.

NAAQS for particulates may become applicable during soil removal operations.

These standards may be considered during assessment of on-site treatment operations and soil removal operations

TLVs could be used for assessing site inhalation risks for soil removal operations.

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TABLE 3-2

POTENTIAL LOCATION-SPECIFIC ARARS AND TBCs

SOLVENTS RECOVERY SERVICE OF NEW ENGLAND, INC. SUPERFUND SITE

Contaminant

Medium/Authori ty

WETLANDS/FLOODPLA





Requirement

NS Clean Water Act (CWA) 404b 1, (33 u s e . 1344 40 CFR 230)

Fish and Wildl i fe Coordination Act(16U.SC, 661)

RCRA Location Standards (40 CFR 264.18)

National Environmental Policy Act-NEPA (40 CFR Part 6)



The Act applies to dredge and fi l l activities. Under this requirement, no activity that adversely affects a wetland shall be permitted if a practicable alternative that has less effect is available.

This regulation requires that any Federal agency that proposes to modify a body of water must consult w i th the U.S. Fish and Wildl i fe Service. This is addressed under CWA regulations at 40 CFR 230.

This regulation outlines the requirements for construction of a RCRA facility on a 100-year f loodplain.

The Act requires that a Floodplain/ Wetlands Assessment be incorporated into the RI/FS.


During the identif ication, screening, and evaluation of alternatives, the effects on wetlands are evaluated. This requirement is applicable t o any action that may impact wetlands.

During the identif ication, screening, and evaluation of alternatives, the effects on wetlands are evaluated. If an alternative modifies a body of water, EPA must consult the U.S. Fish and Wildl i fe Service

A facility located in a 100-year f loodplain must be designed, constructed, operated, and maintained to prevent washout of any hazardous waste by a 100-year f lood, unless waste may be removed safely before f loodwater can reach the facility or no adverse effects on human health and the environment wou ld result if washout occurred. This requirement is applicable if a RCRA facility is located in the 100year plain.

Specific remedial alternatives wi l l detail ail environmental impacts. This requirement is applicable.

http:Act(16U.SC

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TABLE 3-2 POTENTIAL LOCATION-SPECIFIC ARARS AND TBCs SOLVENTS RECOVERY SERVICE OF NEW ENGLAND, INC. SUPERFUND SITE SOUTHINGTON, CONNECTICUT PAGE TWO

Contaminant Requirement Requirement Synopsis

Medium/Authority

WETLANDS/FLOODPLA NS (Continued) Federal Requirements Flood Disaster Protection Act of These acts contain comprehensive criteria for

1973 and National Flood land management and use in floodplains Insurance Act of 1968

State Requirements Connecticut Inland Wetlands and The regulation limits activities that deposit Water Courses Regulations (Title material in, alter, or pollute inland wetlands and 22a) water courses.

Criteria, Advisories, & Wetlands Executive Order (E.O. Under this regulation. Federal agencies are Guidance to be 11990) required to minimize the destruction, loss, or Considered (Federal) degradation of wetlands, and preserve and

enhance natural and beneficial values of wetlands.

Federal TBC Floodplains Executive Order (E.O. Federal agencies are required to reduce the risk 11988) of f lood loss, minimize impact of floods, and

restore and preserve the natural and beneficial value of floodplains.


Portions of the site are in a 100-year f loodplain. This requirement is applicable to any action that may impact floodplains

The regulation is applicable for alternatives that affect wetlands.

Remedial alternatives that involve construction must include all practicable means of minimizing harm to wetlands. Wetlands protection consideration must be incorporated into the planning and decision-making for remedial alternatives. This requirement is applicable to any action that may impact wetlands.

The potential effects of any action must be evaluated to ensure that the planning and decision-making reflect consideration of f lood hazards and floodplains management, including restoration and preservation of natural undeveloped floodplains. This requirement is applicable to any action that may impact the f loodplain.

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TABLE 3-2

POTENTIAL LOCATION-SPECIFIC ARARS AND TBCs

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PAGE THREE

Contaminant Requirement Requirement Synopsis

Medium/Authority

QUINNIPIAC RIVER

Federal Requirements Fish and'Wildlife Coordination The Act limits activities that may impact fish and Act wildl i fe.

State Requirements Connecticut Water Quality The Standards specify criteria for maintaining Standards (Section 22a-426) the quality of the Quinnipiac River

State TBC Establishment of Stream Channel These Sections note that boundaries shall be Encroachment Lines (Section 22a- established along inland waterways wherein no 342 through 22a-350 of the obstruction or encroachment shall be placed Connecticut General Statutes) unless authorized by the CT DEP Commissioner

GROUNDWATER

Federal Requirements EPA's Groundwater Protection This provides policy direction for EPA programs Strategy wi th groundwater responsibility.

State Requirements Connecticut Water Quality Underground injection associated w i th Standards alternatives involving recirculation and tracer

studies are contingent on aquifer designation