Volume I - Text

PHASE 1A .' "" >SITE CHARACTERIZATION REPORT V ~

Volume I - Text

Remedial InvestigationBarkhamsted-New HartfordLandfill Superfund SiteBarkhamsted, Connecticut

Barkhamsted Site PRP Group

April 1993

OBRIENCGEREENGINEERS, INC.

TABLE OF CONTENTS (Continued)

Page

16 Geologic Cross Section B-B1 - Area B & C 17 Test Pit Location and Limits of Refuse Map 18 Ground Water Investigation Map 19 Schematic of Pneumatic Packer Test Equipment 20 Geologic Cross Section C-C1

21 Geologic Cross Section D-D1

22 Overburden Ground Water Elevation Map - January 26, 1993 23 Shallow Bedrock Ground Water Elevation Map - January 26, 1993 24 Intermediate Bedrock Ground Water Elevation Map - January 26, 1993 25 Deep Bedrock Ground Water Elevation Map - January 26, 1993 26 Semi-Quantitative Flow Net E-E1

27 Semi-Quantitative Flow Net F-F1

28 Overburden Ground Water Plume Map - Total VOCs 29 Shallow Bedrock Ground Water Plume Map - Total VOCs 30 Intermediate Bedrock Ground Water Plume Map - Total VOCs 31 Deep Bedrock Ground Water Quality - Total VOCs 32 Ground Water User Survey and Domestic Supply Well Sample Locations 33 Air Sample Location Map 34 Surface Water/Sediment and Leachate Seep Sample Locations 35 Covertype Map 36 National Wetland Inventory Map for the Vicinity of the Site 37 Litchfield County Soil Survey Map 38 Wetland Delineation Map 39 Floodplain Boundary Map

APPENDICES

A Wetland Delineation Report B Resistivity Plots C Grain Size Analysis Results D Soil Boring and Monitoring Well Logs E Hydraulic Conductivity Data and Plots F Ground Water Sampling Logs G Ground Water User Survey Form H Ground Water Analysis Survey Results I Air Particulate DataLogger Results J On-Site Meteorological Station Data K Brady International Airport Meteorological Data L Air Sampling Survey Data Sheets M Wetland Function and Value Assessment Report

DRAFT April 29, 1993

SECTION 1 - INTRODUCTION

1.01 Introduction

The Barkhamsted-New Hartford Landfill Superfund Site (Barkhamsted Site) is

located adjacent to and southwest of Route 44 within the Towns of Barkhamsted and

New Hartford, Connecticut as shown on Figure 1. The landfill, owned and operated

by Regional Refuse Disposal District #1 (RRDD #1), has been used for solid waste

disposal since April 1974 under a Solid Waste Permit (#005-2L) from the Connecticut

Department of Environmental Protection (CTDEP) for operation of a sanitary landfill.

In 1981, the United States Environmental Protection Agency (USEPA)

conducted a Preliminary Assessment for the Barkhamsted Site based on the results of

a 1980 CTDEP inspection. The USEPA recommended that a site inspection be

conducted. The USEPA site inspection was performed in 1987.

Pursuant to Section 105(8)(b) of the Comprehensive Environmental Response,

Compensation and Liability Act (CERCLA), the Barkhamsted Site was proposed for

inclusion on the National Priorities List (NPL) on June 21, 1988 (53 FR 23988). The

Barkhamsted Site was listed on the NPL on October 4, 1989 (NPL final rule update #6,

54 FR 41015). An Administrative Order to conduct a Remedial Investigation/Feasibility

Study (RI/FS) at the Barkhamsted Site between the Barkhamsted Site PRP Group, the

State of Connecticut and the USEPA became effective on October 4, 1991. (Docket

No. 1-91-1128, October 4, 1991).

During December 1991 and January 1992, O'Brien & Gere Engineers, Inc.

performed a Limited Field Investigation (LFI) at the Barkhamsted Site pursuant to an

LFI Work Plan approved by the USEPA in December 1991. The purpose of the LFI

DRAFT 1 April 29, 1993

was to produce a focused Work Plan for the RI. The results of the LFI are presented

in the Remedial Investigation Work Plan, which received conditional approval from the

USEPA effective October 1, 1992.

Fuss & O'Neill prepared and implemented a Scope of Study at the Barkhamsted

Site on behalf of RRDD #1. The objective of the Scope of Study was to satisfy the

requirements of the CTDEP Administrative Order No. 666. This Administrative Order

required RRDD #1 to: 1) investigate the waste materials and disposal activities on-site,

2) determine the potential impact of such activities or such waste on human health both

on-site and off-site, 3) determine the existing and potential extent and degree of soil,

ground water, and surface water pollution, and 4) identify potential impacts of polluted

ground water and surface water on public and private drinking water supplies. The

results of that investigation are summarized in the Remedial Investigation Work Plan

presented in the RRDD #1 Landfill Site Investigation Report, Fuss & O'Neill,

December 1991.

The majority of field work conducted pursuant to the approved Remedial

Investigation Work Plan was performed between October 1992 and January 1993. The

results of this work are presented in this Phase 1A Initial Site Characterization Report.

Remaining work to be completed in connection with the USEPA approved work plan

includes second round sampling and analysis of surface water/sediments and ground

water. In accordance with the approved Remedial Investigation Work Plan, the results

of these efforts will be presented in an addendum to this report.


1.02 Rl Objectives

As presented in Section 1 of the Statement of Work (SOW), the primary

objective of the RI/FS is to assess site conditions and evaluate alternatives to the extent

necessary to select a remedy of the site as defined in the Administrative Order on

Consent. The objectives of the RJ are to:

1. Define the source(s), nature, extent, and distribution of contaminants

released;

2. Evaluate and quantify potential exposure pathways;

3. Provide sufficient information to assess the risks to human health and to

the environment; and

4. Provide sufficient information to evaluate remedial alternatives,

conceptually design remedial actions, select a remedy, and issue a record

of decision.

The Phase 1A Initial Site Characterization represents the principal component

of the RI.

1.03 Purpose and Objectives of Phase 1A Initial Site Characterization

As presented in Section 3 of the SOW, the objective of the Initial Site

Characterization (conducted in accordance with the approved Work Plan during the

Phase 1A Field Investigations) was to conduct field activities and collect field data for

the RI/FS. Information generated during the Phase 1A Initial Site Characterization is

to be utilized to select a remedy and to further define the boundaries of the RI/FS study

area by identifying and characterizing all source areas and determining the extent of

existing contaminants and of environmental effects resulting from releases from the site.


The Site Characterization will provide information sufficient to refine preliminary

identification of potentially feasible remedial technologies and potential Applicable or

Relevant and Appropriate Requirements (ARARs). The Site Characterization will also

provide data needed by the USEPA to perform a Baseline Risk Assessment.


SECTION 2 - STUDY AREA DESCRIPTION

2.01 Introduction

The Barkhamsted Site is located on lands of RRDD #1 adjacent to and southwest

of Route 44 within the Towns of Barkhamsted and New Hartford, Connecticut as

shown on Figure 1. The Barkhamsted Site is on a 97.8 acre parcel of land on the

northern slope of a hill within the Farmington River Valley in the north central portion

of Connecticut, approximately 20 miles northwest of Hartford. The RRDD #1 property

:i is bordered to the northeast by the Barkhamsted Town Garage facility. The remainder

i> of the parcel is bounded by a combination of developed and undeveloped private

property. Landfill operations occur on a area located in the northern area of the property

with refuse overlaying approximately 10.2 acres of this area. The landfill disposal area

extends north to the RRDD #1 boundary, west to the Unnamed Brook which bisects the

RRDD #1 property, east to the landfill access road and south to a drainage ditch

constructed along the Barkhamsted-New Hartford town line (Figure 2).

i

2.02 Study Area Background

1 The Barkhamsted Site was utilized for the disposal of solid waste between April

1974 and August 1988. Since August 1988, the landfill has been utilized only for the

- disposal of bulky and non-processible waste with the exception of a period during

November and December 1988 when the CRRA Mid-Connecticut Waste to Energy

Plant was inoperable. Recycling activities have been conducted at the site since it was

opened.


RRDD#1 was formed in May 1970 by the communities of Barkhamsted,

Colebrook, New Hartford, and Winchester. On September 21, 1972, RRDD#1 received

CTDEP solid waste permit #005-2L based on plans prepared by W.G. Weaver and

Associates. According to these plans, landfilling was to occur in a 24.7-acre area

bounded on the west by a 50-foot buffer along the Unnamed Brook, the town line on j

the south, and the eastern portion of the railroad right of way on the east. The bulky

waste disposal area, or stump dump, was to be separated from the main disposal area.

) This area was to be north of the landfill operation building at a location which is

> currently paved between the landfill office and the transfer station. The original \i

Weaver plans also called for the construction of a fluid pit, although a location was not

specified. The plans called for the construction of terraces with a grade of two percent

to be formed by cutting the natural grade. Individual cells (with 6 inches of cover

between cells) were to be constructed on the terraces, with solid waste landfilling to be

initiated on the western side of the northern toe of the existing landfill. Cell

construction required 6 inches of cover between the cells. Filling was to proceed east

along the front of the landfill and then proceed to the south. It is not believed that this ~] - filling sequence was followed during the early years of landfill operation, but no

| documentation currently exists on specific landfilling operations. ^>

An amendment to the RRDD#1 solid waste permit was issued on January 17,

1974, following submission of a revised operation and management plan dated January

2, 1974. The amendment addressed modifications to service area and entrance road

designs as well as to the stump and brush disposal area. The amended permit required

that all wastes with the exception of stumps and brush be excluded from a 50-foot wide


zone between the Unnamed Brook and the landfill. No refuse was to be allowed to

come into contact with the Unnamed Brook.

The landfill became operational in April 1974. According to CTDEP solid

waste landfill inspection reports from the period of 1974 to 1979, problems were

> reported regarding a lack of daily cover material. Bulky wastes and brush were noted

as the wastes most frequently left uncovered. Ponding of water on the landfill surface <

was also reported to be a problem. The ponding of water is believed to have created

an increase in the amount of leachate resulting from the infiltration of water. Brush and

--, bulky waste were observed to be encroaching on the 50-foot buffer zone which had

been established between the landfill and the Unnamed Brook in the original plans for

the landfill.

In 1981, United States Environmental Protection Agency (USEPA) conducted

a preliminary assessment for the Barkhamsted Site based on a 1980 CTDEP inspection,

and recommended that a site inspection take place. USEPA conducted a site inspection

in 1987. USEPA's site inspection reported that a ground water sample collected and J

analyzed prior to the site inspection contained xylene (92 ppb), toluene (870 ppb), 1,1

-J dichloroethane (86 ppb), 4-methyl-2-pentanone (1700 ppb), and vinyl chloride (170

~] ppb)- In addition, the site inspection reported that industrial oily metal grinding sludges

disposed of at the site contained cadmium, chromium, copper, lead, manganese, nickel

ji and zinc. Leachate from the landfill was observed discharging into the Unnamed Brook

during this site inspection.

A modification to the landfill operating permit was issued on December 16, 1983

based on an updated Operation and Maintenance Plan prepared by Roger H. Whitney,

Inc. in 1982 and updated in 1983. According to this updated plan, landfilling of solid


waste was to be limited to an area bounded by the Unnamed Brook buffer on the west,

the town line on the south, the main access road on the east, and the railroad right of

way on the north. This plan also allowed for a 1,000-foot buffer zone between the

landfill and a domestic well located to the east on U.S. Route 44. Therefore, the area

available for landfilling was reduced to approximately 10 acres. The plan called for

filling to be conducted by constructing cells 9 feet high and 35 feet wide. Cell

construction was to be initiated at the northern portion of the landfill, proceeding from

] east to west with rows of cells to be constructed from north to south. The direction of

-j row construction was to be reversed following completion of the fourth lift of cells.

i On February 27, 1990, a minor amendment was granted to the RRDD#1 solid

waste permit allowing the landfill to accept dewatered sludge from the Winsted Publicly

Owned Treatment Works (POTW). The sewage sludge was brought to the site and

incorporated into the landfill cover material.

Industrial wastes, including metal grinding waste, oily sludge with metal

~j grinding and degreasers, barrels containing unspecified amounts of chlorinated

hydrocarbons and methyl-ethyl-ketone, and keratin (a food processing waste) were

- accepted at the site. Dry metal grinding waste was utilized on site roads and

1 incorporated into the landfill daily cover. CTDEP records state that an industrial waste

pit was operated at the site during the first year of landfill operation (Fuss & O'Neill,

1991b). Information on the pit location, materials placed in the pit, and its duration of

use is limited. Fuss & O'Neill reported that a 1988 CTDEP document refers to

chemical pit operation in the 1970s that received "oily sludge with metal grindings and

degreasers". A drum crushing operation was reportedly located proximal to a scrap

metal area north of the toe of the landfill and northwest of the landfill garage. The


1988 CTDEP document states that one half of the barrels received at the site contained

unspecified amounts of chlorinated hydrocarbons or methyl-ethyl-ketone. There are

also reports of the rejection of wastes, such as cutting oils, from the landfill during

1974. The time period for which the waste pit was utilized and its location are not

precisely known. Reference was made to the location of the waste pit "near the existing

n metal grinding waste cell" in 1974. Metal grinding wastes appear to have been

disposed of-at a variety of locations at the site, including north of the toe of the landfill, *~i

\ in the vicinity of a stone arch, and on roadbeds to the east of the landfill. Therefore,

-i the location of the industrial waste pit cannot be accurately identified.

) The types and quantities of industrial wastes handled at the site are not well

documented in CTDEP records. In March 1981, RRDD#1 was requested by the

CTDEP to eliminate hazardous waste from the facility. In July 1981, the CTDEP

formally approved metal grinding waste for disposal at RRDD#1 since testing indicated

that these wastes were not characteristically hazardous. The CTDEP stipulated that the

metal grinding wastes be kept separate from other refuse. A cell for metal grinding

wastes was specified in the operational plans originally prepared by Roger H. Whitney, 1

Inc. in 1982. This cell was to be constructed at the southern portion of the landfill,

I and metal grindings which had been deposited on an unnamed access road on the

eastern portion of the site were scheduled to be relocated to this cell. The cover

material in the metal grinding cell was to consist of a soil-lime mixture in order to raise

the pH and minimize metal leaching to the subsurface. The plan also proposed that the

metal grinding wastes be mixed with cover materials in the cells due to the

nonhazardous nature of these materials. A new metal grindings cell was required by

the middle of 1984. At that time, some metal grindings were apparently stored on-site


in 55-gallon drums. Existing documents report that the metal grinding waste was

~~ sometimes received heated and placed in piles exceeding 10 feet in height.

In 1983, two complaints were received concerning the presence of a large

number of drums at the landfill. The first complaint, in April 1983, resulted in CTDEP

requesting that 25 drums, which reportedly contained used motor oil, be relocated from /

the vicinity of the oak tree northwest of the landfill building to a paved area on-site.

Fuss & O'Neill reported that the CTDEP collected a composite sample from the drums. 1

j The sample reportedly exhibited a low flashpoint (77°C) and relatively high levels of

lead and cadmium. In November 1983, at least 30 drums were found proximal to the

scrap metal area north of the toe of the landfill and northwest of landfill garage. These

drums were scheduled for crushing, an operation which was apparently centered in this

area of the site. Following investigation into this complaint, the CTDEP formally

notified RRDD#1 that the landfill could not accept hazardous materials for storage or

disposal. The landfill, however, has accepted waste oil for recycling throughout its

operation. Handling of both waste oil and batteries for recycling was reported to and >

it acknowledged by the CTDEP in September 1986.

Presently, the landfill has an active working area of approximately 17 acres, with

1 refuse overlying an area slightly greater than 13 acres. The remaining acreage is utilized

for recycling, offices and other ancillary landfill activities. It is currently open to the

-J public for the disposal of bulky wastes which include construction and demolition

debris. A recycling collection station is operated on-site and is utilized for collecting

glass, plastic, paper, metal, waste oil and paint. Appliances such as refrigerators and

washing machines are deposited in the former drum crushing area and later disposed


of off-site. Sewage sludge is brought to the site and incorporated into the cover

material. Leaf composting is also conducted on the landfill.

Information in this section has been extracted from the December 1991 report

prepared by Fuss & O'Neill and interviews conducted with representatives of Fuss &

O'Neill. In preparing the discussion of historical waste disposal practices, Fuss &

^ O'Neill reviewed information from the following sources: I

Connecticut Department of Environmental Protection (CTDEP)

j Solid Waste Management Unit Files;

CTDEP Hazardous Waste Management Unit Files; j

CTDEP Water Compliance Division Files;

CTDEP Oil and Chemical Spills Division Files;

USEPA Superfund Files;

CTDEP Underground Storage Tank Files;

RRDD#1 Files;

Town of Barkhamsted Files; and

Personal interviews with John Raabe, PhD. (Geologic Services

-1 Geologist) and James Hart (RRDD#1 Landfill Administrator).

A more detailed discussion of waste disposal at the site may be found in the

Landfill Site Investigation (Fuss & O'Neill, 1991b).

i

2.03 Sensitive Environments and Ecosystems

An ecological characterization of the Barkhamsted Site is presented in the

Landfill Site Investigation (Fuss & O'Neill, in 1991b). O'Brien & Gere performed a

preliminary ecological assessment during December of 1991 as part of the Limited Field


Investigation (LFI), the results of which are presented in the Remedial Investigation

"" Work Plan (RI Work Plan). These investigations, along with additional work associated

with preparation of this report to assess the nature and extent of effects of site

contamination on nearby ecological resources, are presented in Section 7.

~i

j 2.04 Climatology

i The climate of Connecticut is generally temperate-humid. The proximity of the

) state to the ocean, which is the dominant factor affecting weather most of the year, has

a moderating effect on temperatures. Thermal lag of the ocean causes the spring to be

typically cool and cloudy and the summer and early fall to be warm and clear. i

Precipitation is generally plentiful and evenly distributed throughout the year. The

quantity of water received in Connecticut by precipitation is approximately twice the

quantity lost by evaporation (National Water Summary 1988-89).

1 2.05 Topography and Drainage i J

The Barkhamsted Site is located on the northern toe of a gentle north to south "1

_j sloping hill. A north to south trending ridge lies to the west at a higher elevation and

1 the floodplain of the West Branch of the Farmington River lies to the east of the y

RRDD#1 property.

-1 The floodplain of the West Branch of the Farmington River is at an elevation

of approximately 400 feet mean sea level (msl) and extends west from the river to

Route 44. Topography from this point slopes up toward the west from an elevation

between 420 feet msl and 430 feet msl in the area of Route 44 to an elevation of

approximately 495 feet msl in the vicinity of the landfill office and maintenance garage. j


A ridge west of the landfill runs southwest to northeast across the western portion of

the RRDD#1 property. Elevations in the vicinity of the ridge range from approximately

510 feet msl on the western side of the landfill to in excess of 800 feet msl along the

crest of the ridge.

Elevations on the landfill range from approximately 500 feet msl on the north

and east portions of the landfill to approximately 590 feet msl at the time of the

topographic survey performed in 1990. Elevations on the southern and western

perimeters of the landfill vary from approximately 550 feet msl to 510 feet msl,

respectively.

A borrow area exists to the southeast and south of the landfill. Excavation has

occurred in this area to provide landfill cover material. Sand and gravel excavation has

occurred, and is an ongoing activity, north of the landfill in the vicinity of the

Barkhamsted Town Garage.

The site is within the Farmington River drainage basin. The Unnamed Brook

originates southwest of the landfill and flows north along the western boundary of the

landfill until it flows off the RRDD#1 property in the vicinity of MW-106 (Figure 2).

After flowing off the property, the Unnamed Brook changes course to the northeast, and

then to the east as it flows through a culvert under U.S. Route 44. The Unnamed

Brook changes from a single channel to a braided pattern between 200 and 250 feet east

of monitoring well nest MW-111.

Drainage from the RRDD#1 property is derived from two sources, precipitation

and seeps occurring at \arious locations around the landfill. Figure 3 illustrates

precipitation drainage path\*a\s. A description of the surface water drainage pattern

follows.


Precipitation Drainage

1. Sedimentation basin #1 lies along the southern edge of the landfill

(Figure 3). Surface water runoff from the southern face of the landfill,

the western portions of the borrow area, and a leaf composting and wood

pile ares flows into sedimentation basin #1. Outflow from this basin is

to the west into the Unnamed Brook.

2. Sedimentation basin #2 is situated to the east of the access road which

runs along the east side of the landfill . Surface water runoff from the

southeastern face of the landfill and the eastern portions of the borrow

and wood pile areas flow into this basin. Outflow is to a small marshy

area which flows to a storm water catch basin along the eastern shoulder

of the main access road.

3. A drainage swale exists across the eastern side of the landfill. This swale

diverts runoff to a storm water catch basin along the western edge of the

main access road.

4. Runoff from the west and northwest faces of the landfill drains into the

Unnamed Brook.

5. Runoff from the north to northeast face of the landfill drains into the site

storm water drain system.

6. The RRDD #1 storm drain system consists of four components based

upon the number of discharge points from the site. Figure 3 illustrates

the RRDD *1 site storm drain system. The storm drain system consists

of gutters and swales which discharge to approximately 25 storm water

catch basins. Catch basins are located along the main access road along

DRAFT 14 April 29. 1993

the eastern edge of the landfill, along the access road from Route 44 to

the recycling area, in the recycling and maintenance building area, and

on the Barkhamsted Town Garage property.

There are three discharges to the Unnamed Brook. The first discharge point to

the Unnamed Brook is a 42-inch diameter pipe north of well nest MW-5. This

discharge includes runoff from the landfill upper access road. A second discharge is

to the same location, from a culvert west of the recycling area which collects runoff

from the vicinity of the landfill office and recycling area. The third discharge to the

Unnamed Brook is a 24-inch pipe located approximately 170 feet north west of the

Barkhamsted Town Garage. This discharge includes run-off from the lower access road

and the Town Garage property.

A separate discharge occurs through a 20-inch pipe which collects storm water

from a depression just south of the intersection of the RRDD #1 main access road and

Route 44. This pipe discharges to the undeveloped property on the east side of Route

44.

Seep Drainage

A component of the leachate sampling program required that the Barkhamsted

Site be surveyed during a wet period to identify all potential seeps at the site. This

survey was conducted on October 15 and 16, 1992, following a light rain event.

Although the seeps identified during the LFI were revisited during the Phase 1A seep

survey, their designations have been changed based on this more recent survey. Twelve

leachate seeps uere identified during the survey as shown in Figure 3. Estimated flow

and discharge points for each seep is presented below:


Seep Estimated Flow Discharge Point

Seep #1* 1-3 gpm Unnamed Brook

Seep #2 <.5 gpm Unnamed Brook


Seep #4 <.l gpm Unnamed Brook

Seep #5 <•! gpm Unnamed Brook


Seep #7 1-2 gpm Unnamed Brook

Seep #8 <.l gpm Unnamed Brook

Seep #9 <.l gpm Catchment Basin #15

Seep #10 <.l gpm Vicinity of MW-110 nest

Seep #11 1-3 gpm Unnamed Brook via storm sewer

Seep #12 0.5 - 1 gpm West of Town Garage

* The source of Seep #1 is Seep #11 via the storm sewer system.

2.06 Surface Soils

Soil types for the site were evaluated by reviewing the Lichtfield County Soil

Survey (USDA, 1970). According to the soil survey, the majority of the soils in the

landfill area are classified as Charlton very stony, fine, sandy loam with slopes from 3%

to 15% (CrC). It should be recognized that surface soils in the landfill area have been

subjected to disturbance since preparation of the soil survey in 1970. Soils surrounding

the landfill include the Charlton (CrC, CrD, ChB), Hollis (HrC, HxE), Hinckley (HkC).

Sutton (SxA, and Leicester, Ridgebury and Whitman (Lg) series (USDA, 1970). The

site soils map for the landfill area is presented as Figure 4 of the Wetland Delineation

Report, included as Appendix A.


2.07 Surface Water

The Unnamed Brook, originating southwest of the landfill, is designated as a

Class B/A stream (CTDEP, 1987). This designation indicates that the stream may not

be meeting Class A water quality criteria or one or more Class A uses such as a

potential drinking water supply, fish and wildlife habitat, agricultural and industrial

supply, and recreational use. The State goal for this stream is Class A.

The Unnamed Brook discharges to the West Branch of the Farmington River

which is located approximately 0.25 miles east of the landfill. The river is designated

as a Class Be surface water which indicates that although the river is not a potable

water supply, it is presumed to meet water quality criteria for the support of cold water

fisheries (CTDEP, 1987).

2.08 Ground Water

Ground water at the landfill is classified as GB/GA by the CTDEP (CTDEP,

1987). The GB/GA classification includes the area north of the Barkhamsted-New

Hartford town line between the Unnamed Brook west of the landfill and Route 44. The

GB/GA designation indicates that the ground water may not be suitable for direct

human consumption without treatment due to waste discharges, spills, or chemical leaks

or land use impacts. The State's immediate goal is to maintain the ground water at

Class B conditions, while the long term goal is to return the ground water to drinking

water quality.

Ground water in the area surrounding the landfill is classified as GA (CTDEP,

1987). This designation applies to ground water within the area of influence of private

and potential public water supply wells. Class GA ground water is presumed suitable


for direct human consumption without treatment. The State's goal is to maintain the

drinking water quality class GA standard.

A discussion of ground water users in the vicinity of the landfill is presented in

Section 4.05 of this report.


SECTION 3 - SOILS AND SOURCES OF CONTAMINATION

3.01 General

The objectives of the Soils and Sources of Contamination portion of the RI/FS

is to evaluate the nature and extent of contaminant sources associated with the

Barkhamsted Site, characterize the site, and to evaluate the contaminant fate and

transport. In addition, data were obtained for the USEPA for conducting a risk

assessment.

The Barkhamsted Site Phase 1A Site Characterization (Phase 1A) was performed

using a phased approach. Initially, investigations were performed in areas that the

Limited Field Investigation (LFI) Summary Report (O'Brien & Gere; September, 1992)

identified as potential source areas. These investigations included geophysical surveys

to further define the horizontal extent of anomalies identified during the LFI. Results

of the LFI investigations and Phase 1A geophysical surveys were used to conduct a soil

gas survey. Finally, a soil boring program was completed based upon the results of the

LFI, Phase 1A geophysical surveys, and Phase 1A soil gas survey. A summary of the

soils and sources of contamination investigations are shown in Figure 4.

3.02 Phase 1A Geophysical Surveys

Geophysical survey techniques consisting of magnetometer, electromagnetic

(EM) terrain conductivity, and electrical resistivity were utilized on and around the

landfill site as shown in Figure 4. The surveys were used to further define LFI

geophysical anomalies, obtain information on buried waste, identify potential

contaminant plumes, and evaluate the site geologic and hydrogeologic conditions.


Two grid areas were established south of the landfill disposal area (Figure 4) to

be utilized for the EM and magnetometer surveys. One grid area is located in Area F,

in the vicinity of GPR anomalies identified by Fuss & O'Neill (Fuss & O'Neill, 1991b).

The second grid area is located in Areas G and H in the vicinity of the metals grindings

waste cell. The grid node spacings at each area varied based on area! extent, but were

established at 50-ft intervals over most of the areas. Where the data indicated the

presence of isolated anomalies, the grid spacings were reduced to 10-ft intervals to

obtain more detailed data in the anomalous areas.

Field Modifications

• Landfill operations resulted in the scrap metal pile having been relocated

to Area F. Due to large amounts of scrap metal at the surface, EM-31

in-phase surveys were not attempted in the southern half of Area F south

of and including grid line N-60 through N-64 (Figure 5).

3.02.1 Magnetometer Surveys

Magnetometer surveys were utilized to evaluate the bulk intensity of the

earth's magnetic field and secondary magnetic fields emanating from buried

ferrous materials.

Methods

The magnetometer surveys were performed using an EG&G Geometries

Model G-816/826 Portable Proton Magnetometer in accordance with the

operational instructions in the equipment manual. Magnetometer surveys were

performed on October 12 and 13, 1992 in Areas G, Area H and Area F,


respectively. Based upon the results of the initial survey, an expanded

magnetometer survey was completed on October 15, 1992 in Areas G, H. and F.

During implementation of the magnetometer survey, base station readings

were recorded at the LFI base station located to the east of the landfill check-in

station on the grass island as illustrated on Figure 4. The purpose of the base

station was to periodically monitor changes in magnetic readings throughout the

day due to diurnal changes in the earth's magnetic field. Generally, measure

ments were taken at the base station on an hourly basis during the operation of

the magnetometer. Magnetometer base station readings are included in Table 1.

Magnetometer readings were recorded at each grid node by orienting the

magnetometer sensor in a northerly direction, and obtaining three readings.

These readings were subsequently averaged and are presented in Table 1. The

averaged readings were plotted on a survey grid map and are illustrated on

Figure 6. The discussion of the magnetometer survey results is presented with

the EM quadrature survey results in Section 3.02.2 below.

3.02.2 Electromagnetic Surveys

Electromagnetic surveys were conducted using the EM-31 in two modes

of operation, an in-phase mode and a quadrature phase mode. EM terrain

conductivity surveys were utilized to evaluate changes in natural ground

conductivities and/or resistivities when operated in the quadrature phase mode.

In-phase mode EM terrain conductivity surveys were utilized to detect buried

metallic objects.


Methods

Terrain conductivity surveys were performed using a Geonics* EM-31

terrain conductivity meter. Prior to initiating the EM-31 quadrature mode

surveys each day, a system check of the unit was completed at the base station

in accordance with the standard operating procedures specified in the equipment

manual. The base station location is illustrated on Figure 4. The EM-31 terrain

conductivity survey was performed in Areas G, H, and Area F on October 12,

1992.

Quadrature phase terrain conductivity data values were measured within

the two surveyed grid areas at each accessible grid node. Data were recorded

in mmhos/meter and are presented in Table 2. The survey data were collected

by first aligning the EM-31 receiver along a north-south axis, then along an east-

west axis. The two values were recorded at each accessible grid node to

evaluate any lateral changes in terrain conductivity. Figures 7 and 8 illustrate

the EM terrain conductivity data collected in north-south and east-west

orientations, respectively.

To evaluate the presence of buried metallic waste materials, the EM-31

receiver was operated in the in-phase mode at each accessible grid 'node within

each of the two grid areas. The EM in-phase survey was performed on October

13, 1992. While conducting the survey, needle deflections on the EM-31

receiver were noted in a field book. These deflections indicate possible

subsurface metallic materials. Areas where the needle deflections indicated the

likely presence of buried metallic waste materials are illustrated on Figure 5.


Results

The results of the EM-31 quadrature mode, EM-31 in-phase mode, and

magnetometer surveys are discussed together in this section. This approach is

utilized to evaluate observed anomalies relative to either background values or

average values for the particular areas of interest. The anomalous areas

delineated using these techniques are likely attributed to buried metallic wastes

or highly conductive materials. Figure 6 illustrates the magnetometer survey

contoured results. Lateral changes in terrain conductivity values across the site

relate to the thickness of the fill. Figures 7 and 8 illustrate terrain conductivity

contours for a north to south and east to west orientation, respectively. Figure

5 shows EM-in-phase anomalous results. A discussion of the results is as

follows:

• Lateral changes in terrain conductivity between grid nodes N-l and N-32

(Figures 7 and 8) correlate with changes in fill thickness in this vicinity.

• Elevated terrain conductivity values coincident with dipolar magnetom

eter data in the vicinity of grid nodes N-l6 and N-l8 (Figure 6) likely

indicates the presence of subsurface ferrous material. This result

supports the LFI geophysical survey results and the suspected location

of the metals grinding waste cell.

• Terrain conductivity and magnetometer values approached background

values south of grid line N-23 to N-33 (Figures 6, 7 and 8) off of the

landfill disposal area indicating fill does not extend south of this line.

• EM in-phase results indicated potential buried metallic waste in the

vicinity of grid nodes N-30, N-31, N-32, and N-36 (Figure 5). This


finding resulted in the installation of soil gas points SG-30, SG-32, SG

35, and SG-36 as discussed in Section 3.03.

• EM terrain conductivity and magnetometer surveys conducted in Area F

generally indicate data values slightly above background indicating that

fill does not exist in this area.

• Anomalous EM terrain conductivity values of less than zero were

detected in both the north-south and east-west orientations in the vicinity

of grid node N-36. A dipole magnetic response was also detected with

the magnetometer in the vicinity of grid nodes N-56, N-57, and N-58.

This is likely indicative of buried ferrous materials which correlates well

with EM in-phase data that indicates strong responses to subsurface

ferrous materials in the vicinity of grid nodes N-56 and N-58. This

finding resulted in the installation of soil gas points SG-20, SG-21, and

SG-22 as discussed in Section 3.03.

• Although EM terrain conductivity surveys were performed in the

southern portion of Area F, data appear to be influenced by the surface

scrap and are most likely not indicative of subsurface conditions.

3.023 Resistivity Surveys

Fourteen electrical resistivity surveys were used to evaluate vertical

heterogeneities in the subsurface materials, the depth to the water table,

overburden thicknesses, and depth to bedrock.


Methods

The resistivity surveys were conducted with the Bison Model 2390 Signal

Enhancement Earth Resistivity System and Schlumberger electrode configura

tion. The Schlumberger configuration requires the spacing of the two inner

electrodes to remain constant. The spacing of the two outer electrodes varies to

provide greater depth sensitivity. The locations of the resistivity soundings are

illustrated on Figure 9.

The current electrode spacings (AB) for the individual resistivity

soundings varied in length from 200 to 400 feet. Potential electrode spacings

(MM) were increased when the potential voltage difference dropped below 1.0

millivolts. The collected resistivity data were reduced using the computer

program "A Computer Program for the Automatic Interpretation of

Schlumberger Sounding Curves Over Horizontally Stratified Media", 1973, by

A.A.R. Zhody; NTIS PB-232-703, along with RESIX, a computer software

modelling package for resistivity data by Interpex Limited. The computer

processed data were used to provide estimates of the depth to ground water and

bedrock. The interpreted data is summarized on Table 3. Computer processed

resistivity plots and data sheets are included in Appendix B.

Results

Bedrock elevations were estimated across the site from the resistivity data

and compared to depths obtained from monitoring well logs. A bedrock

elevation map was prepared from data obtained from the bedrock borings. The

estimated depths to bedrock were then superimposed on the bedrock elevation

map to determine how well the estimated bedrock depths obtained from the


resistivity surveys correlated with the bedrock depths obtained from the bedrock

borings. The results are as follows:

• Five resistivity surveys (R-2, 4, 6, 7, and 12) provided acceptable depth

to bedrock/overburden thickness data. These surveys resulted in an

average of 15 percent difference between the bedrock elevations assessed

from bedrock monitoring wells and the estimated bedrock surface

ascertained through the resistivity surveys. Bedrock elevation data

obtained from these five surveys fill in data gaps where no wells or

borings exist. The level of confidence in the accuracy of the data is high

due to good correlation of the data.

Resistivity surveys R-l, 3, 5, 8, 9, 10, 11, 13, and 14 (Figure 9) did not

produce highly correctable data. The average percent difference

between the conceptualized bedrock surface and the estimated bedrock

surface ascertained through the resistivity surveys is approximately 63

percent. The inability to approximate the bedrock surface at the above

survey points can be attributed to the following:

• R-l was completed in an area with a substantial change in

elevation which may have obscured interpretation of the bedrock

surface.

• R-3 was completed over a subsequently discovered large diameter

steel culvert which prevented adequate electrical penetration to

the subsurface.


R-5 and R-13 were completed in an areas where highly conduc

tive leachate may have prevented adequate electrical penetration

to the subsurface.

• R-8, R-10, R-l 1, and R-14 were completed in areas with resistive,

hard packed, dry sands and gravels which prevented adequate

electrical coupling and electrical penetration to the subsurface.

• R-9 was completed in an area of loose, highly organic soils which

prevented adequate electrode coupling and electrical penetration

to the subsurface.

• Bedrock elevation information obtained from the bedrock wells around

the site indicate bedrock dipping to the north-northeast (Figure 10). The

bedrock elevations estimated from resistivity surveys B-2, 4, 6, 7 and 12

generally fall within the bedrock contours created from well information

as illustrated on Figure 10.

• Water table elevations were estimated from the resistivity surveys. The

water table elevations estimated from the surveys were compared to the

water table elevations from overburden wells as presented in Table 4.

The results are as follows:

• Water table depths estimated from soundings R-l, R-5, and R-l2

correlate well with water table elevations at those locations. The

average difference between actual water table elevations and the

estimated water table elevations determined from resistivity is

approximately 9 percent.


Water table depths estimated from soundings R-2, 3, 4, 6, 7, 8, 9,

10, 11, 13, and 14 showed large deviations from the water table

elevations measured on January 26, 1993. An average difference

of 198 percent was calculated for these soundings.

• Difficulties were encountered in trying to identify the limits of fill

and fill thicknesses from the resistivity data. Changes in the

computer modelled resistivity data appear to represent saturated

overburden materials and overburden/bedrock interfaces.

Discemable changes in resistivity due to fill materials were not

evident in the models.

3.03 Soil Gas Sampling

3.03.1 Introduction

The following summarizes the soil gas survey performed at the

Barkhamsted Landfill Superfund Site between the dates of November 3, 1992

and December 3, 1992.

Two portable gas chromatographs (GCs) were used to analyze 165 soil

gas samples. The objective of the soil gas sampling was to semi-quantitatively

evaluate the concentration, chemical composition, and horizontal extent of

volatile organic compounds (VOCs) in the subsurface soil, to a depth of 3 feet

below grade, at eleven areas on-site. The areas investigated included: A, B, C,

E, F, G, J. K. the Recycling Area, previously cleared area #1, and previously

cleared area =2, as shown in Figure 11.


3.03.2 Methods

Sample Locations

Fifty-five sample locations were initially staked based on the

results of the LFI soil gas and geophysical surveys. Consistent with the

procedures outlined in the Field Sampling Plan (FSP) Appendix FSP-B,

additional locations were added based on initial sample results.

Presented in the following table are the number of initial samples and the

total number of samples collected for each area of study. In most

instances, additional soil gas samples were installed outside of the

original area of investigation. Soil gas sampling locations are illustrated

in area detail maps on Figures 11A through 11F.

Area of Investigation Initial Number of Samples Total Number of Samples

Area A 4 10

Area B 2 15

Area C 6 30

Area E 5 16

Area F 7 19

Area G 12 32

Area J 4 13

Area K 5 6

Previously Cleared Area 1 4 18

Previously Cleared area 2 4 4

Recycling Area 2 2

Soil Gas Sample Collection

Soil gas samples were collected using dedicated aluminum shield

points attached to a length of teflon tubing. The teflon tubing/shield


point assembly was driven to depth of 3 feet using hardened steel probes

(7/8" OD) and an electric impact hammer. Prior to collection of a

sample, the hardened steel probe was retracted 3 to 6 inches to expose

the vapor intake slots of the shield point. One hundred milliliters (ml)

of soil gas was then purged from the system to minimize ambient air

contributions to sample results. Soil gas samples for GC analysis were

collected by attaching a 50 ml glass syringe, equipped with a teflon

stopcock, to the teflon tubing/shield point assembly and drawing back the

plunger. The syringe stopcock was then closed to secure the sample and

the syringe was transported to the office trailer for analysis. A vacuum

gauge was placed in-line during collection of soil gas samples to

qualitatively evaluate soil porosity in each area of collection. A 100 ul

gas-tight syringe was used to extract an aliquot of sample from the 50 ml

syringe for injection into the Photovac GC and 10 ml of sample was

drawn into the Sentex GC directly from the 50 ml syringe.

Field Modifications

Analytical instruments - Due to operating problems incurred with

the Hewlett-Packard 5890 Series II GC, the Photovac and Sentex

GCs were substituted. The substitution was communicated to

EPA prior to initiating the soil gas survey. Analysis protocols

established for the Hewlett-Packard were unchanged.

Chemical concentration action level - As stated in the FSP, "If a

VOC anomaly (i.e. > background total VOCs with portable GC)


is detected, then the soil gas survey will be expanded on a grid

with a 50-foot spacing". The action level of greater than

background was modified. Instead, the preliminary results for

each area of study were discussed with the EPA Project Manager

to define additional soil gas locations to be used to accomplish

the survey objectives. This approach was adopted in an attempt

to delineate each area of study effectively while minimizing the

number of samples required to do so. It should be noted that

preliminary results were obtained by totalling the chromatogram's

peak area and quantifying using the benzene response factor,

only. Since the final results were quantified on an individual

peak basis, results may vary slightly from preliminary results.

The difference is a result of the different response factors for the

calibrant compounds used for the survey.

GC initial calibration - Initially GC calibration was performed by

using one standard concentration and adjusting the instrument

gain to mimic varying concentrations. Subsequently, calibrations

were performed in accordance with the protocols by running three

unique concentration standards at a fixed instrument gain. A

comparison of the two methods indicated both provided similar

results.

Documentation of the standards preparation log - Metcalf and

Eddy, USEPA oversight personnel requested that the O'Brien and

Gere GC operator expand documentation related to the


preparation of standards. Therefore, in addition to documentation

denoted on the chromatograph printout, the concentration of each

calibrant was written on the standards chromatograph report

sheets.

Multi-component standards - Metcalf and Eddy, the US EPA

oversight personnel, requested that standards be injected

individually, rather than as part of a multi-component standard

mix, to minimize potential errors associated with misidentification

of constituents. Therefore, individual standards were prepared for

verification of chemical retention time.

Vacuum gauge for sample collection - Initial vacuum gauge

readings were inconclusive due to the poor cohesiveness of

surface soils. These observation resulted in the discontinued use

of vacuum gauges. The use of the vacuum gauge was

reimplemented in accordance with the protocols, upon a request

from Metcalf and Eddy oversight personnel.

GC Calibration

A Photovac 10S70 portable GC equipped with a CPSIL-5

capillary column, isothermal column oven and 10.6 eV photoionization

detector, and a Sentex Scentograph portable GC equipped with a SP

2100 packed column, isothermal column oven, and an electron capture

detector, were used to complete the analysis of the soil gas samples. The

GCs were calibrated to the compounds identified during the Fuss and


O'Neill (1990) investigation (benzene, toluene, xylene, vinyl chloride,

trans-1.2-dichloroethene, trichloroethene, methyl ethyl ketone, and methyl

isobutyl ketone). The GC calibration consisted of both initial calibration

and continuing calibration.

Initial Calibration: Prior to initiation of field activities, the

Photovac GC was calibrated to the aromatic and ketone compounds and

the Sentex to the chlorinated compounds. The Photovac GC was

calibrated to benzene, toluene, xylene, methyl ethyl ketone, and methyl

isobutyl ketone, and the Sentex GC was calibrated to vinyl chloride,

trans-l,2-dichloroethene, and trichloroethene. A four point calibration

was completed for each of the above mentioned compounds, including

a zero level standard or method blank and three concentration levels.

Continuing Calibration: During the field investigation, the

Photovac was calibrated to a mid-level concentration standard of

benzene, toluene and xylene and the Sentex to a mid-level concentration

standard of vinyl chloride, trans-1,2-dichloroethene, and trichloroethene.

Continuing calibration was performed at the start of each day, and after

every ten sample analyses.

Sample Quantification

A least squares regression was performed to develop an equation

for each calibrant which relates peak area to sample concentration.

Results of sample analyses were quantified by comparison to the

calibration equations. Sample peaks which were consistent with a


calibrant peak, on the basis of retention time, were quantified using the

corresponding calibration equation. Sample peaks inconsistent with

calibrant standards were grouped and labelled Other VOCs. Other VOCs

were quantified using an average of the calibration equations.

Quality Control

The following quality control measures were taken during the

investigation: 1) GC blanks, 2) equipment decontamination, 3) sample

collection blanks, 4) syringe blanks, 5) sampling variability evaluation,

and 6) accurate record keeping.

1) GC Blanks: GC blanks were run at the beginning of every day.

A GC blank consists of an analytical run without introduction of

sample.

2) Equipment Decontamination: The hardened steel probes used to

install the aluminum shield points were decontaminated between

each sample using a soapy water wash followed by a water rinse.

3) Sample Collection Blanks: A sample collection blank was

collected once per day. The sample collection blank was obtained

by passing ambient air through the sample collection apparatus

and into a 50 ml glass syringe.

4) Svringe Blanks: A syringe blank was performed after each

calibrant set and after each environmental sample which exhibited

detectable concentrations of VOCs. Syringe blanks were obtained

from the 50 ml collection syringe using a 100 /xl gas tight


syringe. If VOCs were observed in the syringe blank, additional

blanks were run until blank response returned to background.

5) Analytical Variability: In order to assess the variability associat

ed with analysis of environmental samples, three sets of duplicate

samples were analyzed. Duplicate samples were obtained by

collecting two samples from one sampling point. The relative

percent differences (RPD) ranged from 0.59% to 8.76%, based on

total VOC concentrations. This result is within QA/QC criteria.

6) Record Keeping: Chromatograms were taped into analytical note

books. Information detailed on each chromatogram included:

sample number, site name, date/time of collection, date/time of

analysis, column and detector type, injection volume, back-flush

time, carrier gas flow rate, and instrument gain setting. In

addition to the information printed on the chromatographs,

documentation of standard preparation was logged, and field notes

(i.e. ground water was encountered at 1 foot) were documented

on the data sheets.

7) Instrument Performance: A four point calibration was completed

for each calibrant compound to establish a retention time window

and calibration equation (response factor) for each. The GCs

were also calibrated to the calibrant compounds (at the start of

each day) to evaluate variability in instrument performance

throughout the investigation. Results of the initial and continuing

calibration are summarized and presented in the raw data. R


squared values ranging from 0.992 to 0.999 were obtained for the

initial calibration.

3.03.3 Results

The objective of the soil gas survey was to delineate the areal extent of

VOCs in the vadose zone and to aid in the selection of soil boring locations.

These objectives were accomplished for each of the eleven areas of

investigation. Figures FSP-11 shows the areas of investigation and provides an

index for Figures 11A through 1 IF which illustrate the extent and results of soil

gas surveys within each area of investigation. A discussion of the results

obtained for each area is presented in the following paragraphs.

Area A - Approximately ten samples were utilized to delineate Area A

(Figure 11 A). The highest concentrations in this sample group were observed

at locations SG-3B and SG-3 which exhibited total VOC concentrations of 32.3

and 57.4 ppm, respectively. Sample SG-3 was situated at the southeastern

boundary of Area A, and Sample SG-3B was located 50 feet to the east. The

northern extent of VOCs was defined by sample SG-2A, situated 50 feet north

of sample SG-2. To the west, the extent of VOCs in soil gas was defined by

samples SG-2DD and SG-2DA, situated 50 feet west of samples SG-2D and

SG-2A, respectively. No additional samples were installed to delineate VOCs

in the southern direction, due to the low concentration observed in sample SG-1

and the presence of perched ground water in this area. The primary constituents

observed in Area A were toluene and xylene. The remaining calibrant


compounds, with the exception of methyl ethyl ketone, were observed at

concentrations ranging from 0.015 to 2.7 ppm.

Area B - Approximately fifteen samples were collected to delineate Area

B (Figure 11 A). The highest concentrations of VOCs were detected in the

southern portion of Area B. Samples SG-5, SG-5C, SG-5DD, and SG-9

exhibited total VOC concentrations of 10.5, 30.6, 26.0, and 44.2 ppm,

respectively. The primary constituents observed in this area were benzene,

toluene and xylene. The chromatographic pattern observed from samples

collected from Area B was consistent with that of a petroleum hydrocarbon

residue. Trace concentrations of the remaining calibrant compounds, excluding

MEK, were also detected. The extent of VOCs to the south was the toe of the

landfill, SG-3A, SG-6 and SG-9AW to the north, and SG-9AB, SG-9B, and SG

9C to the east. The western extent of VOCs was defined by Area A.

Area C - Approximately thirty samples were utilized to delineate

subsurface VOCs in Area C (Figure 11 A). Each of the eight calibrant

compounds were detected in this area. Samples LISG-106, LISG-106D, LISG

106AB, and SG-11Z, situated in the northern portion of Area C, exhibited the

highest total VOC concentrations in this area, at 55.6, 49.1, 27.7, and 10.8 ppm,

respectively. The remaining 25 samples exhibited total VOC concentrations

ranging from non-detect (<0.010) to 3.3 ppm. The areal extent of VOCs was

established by samples LISG-106AADA and LISG-106AAA to the north, LISG

106ABA. LISG-106ABB, LISG-106B, LISG-106Y, and SG-11B to the east,

LISG-106AADD, SG-8A, SG-8D, SG-8Y, and SG-7 to the west, and Area B to

the south.


Area E - Approximately 19 samples were collected to delineate the extent

of subsurface VOCs in Area E (Figure 11B). Samples LISG-62DA, LISG-62C,

SG-16Z, and LISG-62-2, situated in the western portion of Area E, exhibited

total VOC concentrations of 11.5, 19.7, 15.4, and 3.8 ppm, respectively. The

twelve remaining samples exhibited total VOC concentrations ranging from non-

detect to 2.97 ppm. A mix of chlorinated and aromatic hydrocarbons were

observed in Area E. The chromatographic fingerprint observed in samples with

relatively high total VOC concentrations was consistent with that of a petroleum

hydrocarbon residue. Subsurface VOCs were found to extend approximately

100 feet north of SG-16, the northern most initial sample, as defined by sample

LISG-62DAA. The western extent of VOCs was defined by samples LISG

62DAD, LISG-62DD, and SG-13 and the eastern extent by samples LISG-62A,

LISG-62B, and SG-17. No additional samples were collected to the south of the

initial sample points.

Area F - Approximately nineteen samples were utilized to delineate

Area F (Figure 11C). Total VOC concentrations observed in the these samples

ranged from non-detectable (<0.025 ppm) to 4.79 ppm. Compounds detected

in this area included vinyl chloride, benzene, MEK. (one sample), MIBK. (one

sample), toluene and xylene (one sample). The highest total VOC concentration

was observed in sample SG-20D, located in the western portion of Area F.

Total VOC concentrations dropped off to near background within 50 feet in each

direction. The northern extent of subsurface VOCs was defined by samples SG

20DAA and SG-23A, the western extent by samples SG-20DAD, SG-20DD and


SG-20DC, and the eastern extent by samples SG-23B and SG-24. No additional

samples were collected south of the initial sample locations.

Area G - Thirty-two samples were collected to delineate subsurface

VOCs in Area G (Figure 11D). Total VOC concentrations in the 32 samples

ranged from non-detect (O.025) to 20.59 ppm. The highest total VOC

concentrations were observed in the northwestern portion of Area G, in samples

SC-25C, SG-27, and SG-27Z. Benzene, toluene and xylene were the major

constituents detected in Area G, while the remaining calibrant compounds were

detected at trace concentrations. The chromatographic pattern observed for

samples from Area G was consistent with that expected for a petroleum

hydrocarbon residue. Sampling was advanced approximately 150 feet to the

south, 100 feet to the west, and 100 feet to the east of initial sample locations,

before near background VOC concentrations were observed. No additional

sampling was necessary in the northern direction.

Area J - Approximately thirteen samples were collected for GC analysis

from Area J, the suspected hazardous waste disposal area (Figure 11B). Total

VOC concentrations observed in samples collected from Area J ranged from

non-detect (<0.025 ppm) to 86.63 ppm. Compounds detected in this area

included vinyl chloride, MEK (one sample), benzene, TCE, MIBK, toluene and

xylene. The highest soil gas concentrations were observed at locations SG

37DC, SG-37DCC, and SG-37D, situated along the eastern boundary of the

landfill.


Area H - Soil gas samples SG-28CCB, SG-32. and SB-35 were installed

in the vicinity of Area H (Figure 1 ID). Results of these soil gas points did not

indicate the need to expand the soil gas survey into Area H.

Area K - Approximately six samples were collected for GC analysis

from Area K (Figure 11B). The total VOC concentrations observed in Area K

samples ranged from non-detect (<0.025 ppm) to 0.61 ppm. The calibrant

compounds observed in samples collected from Area K included vinyl chloride,

DCE, benzene, toluene, and xylene. The concentrations observed in samples

collected from this area are not consistent with that expected for a contaminant

source area.

Recycling Area - Two samples were collected from the Recycling Area

(Figure HE). Samples SG-44 and SG-43, exhibited total VOC concentrations

of non-detect (<0.025 ppm) and 0.31 ppm, respectively. Sample SG-43

exhibited trace concentrations of vinyl chloride, benzene, and toluene. No

additional samples were collected to further define the area.

Previously Cleared Area #7 - A total of 22 samples were collected to

delineate subsurface VOCs in Previously Cleared Area #1 (Figure 11C). Total

VOC concentrations ranged from non-detectable (O.025 ppm) to 13.83 ppm.

The highest total VOC concentrations were observed in samples SG-49CC. SG

49CCY, SG-49CD, and SG-49CDZ, situated in the southwestern portion of the

area. VOCs inconsistent with calibrant compounds made up the bulk of the total

VOC concentrations observed in samples collected from this area. Calibrant

compounds detected included vinyl chloride, toluene and xylene. The


contaminants extended approximately 150 feet to the south, 100 feet to the west,

and 50 feet to the east of the initial points (SG-49, 50, 51, and 52).

Previously Cleared Area #2 - Four samples were collected to delineate

subsurface VOCs in Previously Cleared Area #2 (Figure 11F). Total VOC

concentrations observed in the four samples ranged from non-detect (<0.025

ppm) to 0.50 ppm. Calibrant compounds detected include vinyl chloride, DCE,

and toluene. Based on the low total VOC concentrations observed in the four

initial samples, no additional samples were collected from this area.

In summary, the objectives of the soil gas survey were to delineate the

area! extent of subsurface VOCs and aid in the selection of soil boring locations.

These objectives were met by tracking the extent of VOCs in each area until

near, background total VOC concentrations were obtained in each direction, or

until an area was delineated to the mutual satisfaction of O'Brien and Gere and

USEPA. In addition, soil gas data were reduced in the field to provide site

personnel with the preliminary data necessary to select locations for additional

soil borings. Total VOCs typically associated with potential source areas are

greater than 1 ppm. Seventy percent of the Phase 1A soil gas points were less

than 1 ppm, which indicates that the potential sources areas outside the landfill

disposal area are not VOC source areas.

3.04 Landfill Gas Sampling

The following summarizes the landfill gas survey performed during November

and December 1992. The objective of the survey was to qualitatively evaluate the

presence of landfill gas at the site (primarily methane) and the potential for off-site


migration of landfill gas. Landfill gas sampling locations and results are illustrated on

Figure 12.

3.04.1 Methods

Sample Locations

A total of twelve sample locations were initially selected for

sampling and analysis. The landfill gas sampling was conducted around

the periphery of the landfill to the north, east, and south of the main fill

area to evaluate the potential migration of landfill gas. Landfill gas

samples were not collected along the west side of the main fill area

based on the assumption that the Unnamed Brook acts as a barrier for the

migration of landfill gas. The landfill gas samples collected were

analyzed in the field using a Gas-pointer model H combustible gas

indicator.

The landfill gas samples were collected at 200-foot intervals

around the main fill area at the locations indicated on Figure 12. If

methane was detected at concentrations greater than 2% at any given

sampling location, additional landfill gas samples were collected to better

delineate the extent of elevated landfill gas readings. Additional samples

were situated at locations 100 feet on either side of the point at which

methane was detected at greater than 2 percent. Additional samples were

collected near samples LG-2 and LG-3, the only initial samples

exhibiting methane gas readings of greater than 2 percent.


Sample Collection

Landfill gas samples were collected using dedicated aluminum

shield points attached to a length of teflon tubing. The teflon tub

ing/shield point assembly was driven to depth of 3 feet using hardened

steel probes (7/8" OD) and an electric impact hammer. Prior to

collection of a sample, the hardened steel probe was retracted 3 to 6

inches to expose the vapor intake slots of the shield point. A sample was

collected by connecting the Gas-pointer combustible gas analyzer directly

to the teflon tube.

Sample Analysis

The landfill gas samples were analyzed using the Gas-pointer

combustible gas analyzer. Initially each sample was analyzed using the

0 to 4% combustible gas scale. If 'the instrument reading stabilized

within this range (0 to 4%) the result was documented. If the meter

showed greater than 4% gas, the instrument was switched to the 0 to

100% scale and the percent combustible gas was documented.

Instrument Calibration

The Gas-pointer calibration consisted of 1) initial calibration, and

2) continuing calibration.

Initial Calibration - Prior to analysis of landfill gas samples, a

two point calibration was performed for methane, consisting of a zero


level standard or method blank and one 15% methane concentration

standard.

Continuing Calibration - was conducted prior to each sample

being analyzed by checking the internal standard according to

manufacturer's specifications and checking the zero concentration using

ambient air.

3.04.2 Results

Results of the landfill gas sampling are summarized on Figure 12. Two

initial landfill gas samples detected methane concentrations greater than 2

percent. Samples LG-2 and LG-3 (Figure 12) exhibited methane concentrations

of 90% and 10%, respectively. These samples were situated in the northern

portion of landfill, to the west of the landfill office. Additional landfill gas

sampling points LG-2A, LG-2D, LG-3 A, LG-3B, LG-3D, LG-3DA-1 were

installed to further delineate LG-2 and LG-3. As indicated on Figure 12, landfill

gas was not detected at points LG-2A, LG-3DA, and LG-3D. The elevated

methane concentrations observed in this area are likely a result of fill which

exists in this area. The results of the landfill gas sampling indicated that landfill

gas is limited to the vicinity of fill areas.

3.05 Surface Soil Sampling

Twenty-four surface soil samples were collected at the Barkhamsted Site for use

in completing the L'SEPA Risk Assessment. The locations of surface soil samples SS-1


to SS-24 are illustrated on Figure 4. The locations of surface soil samples within each

potential source area are shown on Figures 13A through 13F.

Surface soil samples SS-20 and SS-21 were collected from the Murray/Jones

property and Yahne property, respectively. Locations of these samples were reviewed

and selected with concurrence of the USEPA oversight personnel.

3.05.1 Methods

Surface soil samples were collected using a stainless steel hand auger.

At each sampling location, the hand auger was advanced to 6 inches below the

ground surface. A stainless steel spoon was utilized to remove and discard the

thin layer of soil which was in contact with the hand auger, and the remaining

sample was placed into a pre-cleaned 4 oz laboratory sample container. This

sample was submitted for TCL volatile analysis. The hand auger was then

advanced to 12 inches, and a stainless steel spoon was used to collect soil from

throughout the 12 inch column into a stainless steel bowl. The soil sample was

homogenized in the bowl and placed into a pre-cleaned laboratory sample jar for

the remaining TCL/TAL analyses. A portion of the homogenized sample was

collected and for grain size analysis using ASTM Method D-422-63. Grain size

analysis results are included in Appendix C.

3.05.2 Field Modifications

Surface soil sample SS-23 was relocated from the southeast side of the

landfill to the north to northeast side of the landfill (Figure 13C). This was the

result of landfill operations regrading and planting grass at the original proposed

location.


3.05.3 Results

Each surface soil sample was shipped to Pace Laboratories, Inc. in

Wappingers Falls, NY utilizing approved chain-of-custody procedures and

analyzed for TCL/TAL parameters listed in Table 5. Analysis results for

volatiles, semivolatiles, pesticides/PCBs and inorganics are included in Tables

6A through 6D, respectively. The following is a discussion of the analytical

results.

Background Samples

Surface soil samples SS-1 and SS-2 were collected to assess background

conditions at the site. The locations of the soil borings are depicted on Figures 4 and

ISA. The following conclusions were reached:

• Background VOCs levels were below the method detection limit in SS-1

and SS-2.

• 1,4-dichlorobenzene at 95 ^g/kg> an<^ fluoranthene at 23 /xg/kg were

detected in background sample SS-1.

• The compounds Dieldrin, 4,4-DDE, and 4,4-DDT were detected in SS-1

at estimated concentrations of 0.97 /ig/kg, 1.9 /xg/kg, and 0-21 Mg/kg,

respectively. These concentrations are all below the quantitation limit.

PCB/pesticides were not detected in SS-2.

• Background metal concentrations reveal consistent results for both SS-1

and SS-2. The concentrations provide a range in which to compare

metal concentrations detected in surface soils at other locations at the

Barkhamsted site.


AREA A

Surface soil samples SS-8, SS-10, SS-11, SS-12, SS-13, and SS-14 were

installed adjacent to Area A soil borings as shown on Figure 13B. The following

conclusions were reached for this area:

• VOCs were not detected in Area A surface soils.

• Twenty-two semivolatile constituents were detected in Area A ranging

from 17 jig/kg naphthalene in SS-11 to 3800 ng/kg of benzo(k)

fluoranthene in SS-10.

• Pesticides detected in the Area A surface soils included aldrin, alpha-

chlordane, 4,4-DDD 4,4-DDE, endrin ketone, gamma-chlordane, endrin

aldehyde, 4,4-DDT and methoxychlor. Concentrations ranged from 0.69

jig/kg, 4,4-DDE in SS-11 to 26 /xg/kg, 4,4-DDD in SS-10.

• Area A surface soil metal concentrations are discussed as follows:

With the exception of SS-8, metal concentrations elevated above

background were detected in each Area A surface soil sample.

Elevated metal concentrations ranged from less than two times

background (barium, calcium, and vanadium) to 273 times

background (SS-13;chromium).

AREA B

Surface soil samples SS-16, SS-18 were collected adjacent to soil borings

installed within Area B as illustrated in Figure 13B. The following conclusions were

reached for Area B:

SS-16 and SS-18 VOC analytical results were all below the method

detection limit.


Nineteen semivolatile constituents were detected in Area B ranging from

21 jig/kg of 2-methylnaphthalene in SS-18 to 4800 /ig/kg of pyrene in

SS-16.

• PCB/pesticide data for Area B surface soil samples are discussed below.

PCB/pesticides detected in SS-16 included 4,4-DDT at 5.2

and 4,4-DDE at 2.3 /ig/kg.

PCB/pesticides detected in SS-18 included 4,4-DDE at 1.5

gamma-chlordane at 0.99 Mg/kg> an<^ endrin ketone at 3.5

• Elevated concentrations of metals were found in each soil sample as are

discussed as follows:

Sodium, nickel, and lead were detected above background

concentrations in SS-16. The concentrations of sodium and zinc

ranged from less then two times background (sodium) to six times

background, respectively.

Barium, potassium, sodium, nickel, and lead were detected above

background in SS-18. Concentrations ranged from less than two

times background for barium, potassium, sodium, an nickel to

seven times background for lead.

AREA C

Surface soil samples SS-17 and SS-19 were collected within Area C as shown

in Figure 13B. The following conclusions were reached for Area C:

• VOCs were not detected above the method detection limit in Area C

surface soil samples.


• Three semivolatile constituents were detected in Area C surface soil

samples ranging from 17 /xg/kg of phenanthrene in SS-17 to 61 /ig/kg of

fluoranthene in SS-19.

• Pesticides detected in Area C included 4,4-DDT, 4,4-DDE, gamma

chlordane, endrinketone, and methoxyclor. Concentrations ranged from

0.70 jtg/kg of gamma chlordane to 3.5 ng/kg of endrine ketone.

• Elevated metal concentrations were detected in each surface soil sample;

however, concentrations were less than two times the background values.

AREA D

Surface soil samples SS-7 and SS-23 were collected in Area D as shown in

Figure 13C. SS-23 was collected in the vicinity of a stressed vegetation area. Results

of these analyses are discussed as follows:

VOCs were not detected above the method detection limit in SS-7 and

SS-23.

• Four semivolatile constituents were detected in Area D surface soil

samples. Concentrations ranged from 35 /zg/kg of phenanthrene in SS-7

to 110 ng/kg of pyrene in SS-23.

• PCB/pesticides results detected 4,4-DDE at an estimated concentration

of 0.42 jig/kg in SS-23. PCB/pesticides were not detected above the

method detection limit in SS-7.

• Elevated concentrations of metals, as compared to background, were

detected in B-7.


Elevated metals were detected in SS-7 with concentrations

ranging from less than two times background for aluminum,

arsenic, chromium and iron to three times background for nickel.

Sodium and lead were elevated above background values in SS

23 but were two times below background.

AREA E

Surface soil sample SS-3 was collected adjacent to soil boring B-3 as shown in

Figure 13C. The results of the sample are discussed below:

• The volatile compound 2-butanone was detected in SS-3 at an estimated

concentration below the quantitation limit. No other volatile constituents

were detected in SS-3.

• Pyrene was the only semivolatile detected in SS-3, at an estimated

concentration of 9 îg/kg.

• PCB/pesticide concentrations were below the method detection limits in

SS-3.

• All metal concentrations in SS-3 were within the background range.

AREA F

Surface soil samples were not collected in Area F.

AREA G

Surface soil sample SS-9 was collected within Area G and SS-15 was collected

to the east of Area G as illustrated in Figure 13E. Results of the TCL/TAL analyses

are discussed as follows:

VOCs were all below the method detection limit in SS-9 and in SS-15.

• Area G surface soil semivolatile results are discussed as follows:


1,4 dichlorobenzene was detected in SS-9 at 84 /xg/kg.

Eighteen semivolatile constituents were detected in SS-15 with

concentrations ranging from 29 /xg/kg of 2-methylnaphtalene to

4200 jig/kg of pyrene.

PCB/pesticide analytical results detected 4,4-DDE in SS-15 at a

concentration of 25 /xg/kg. PCB/pesticides were not detected in SS-9.

• Results of analyses for SS-9 and SS-15 are discussed as follows:

The metals detected in SS-9 which were above the background

range were silver, arsenic, chromium, cobalt, iron, nickel, lead,

and zinc. Concentrations ranged from less than two times

background (iron) to 18 times background (chromium).

The metals which were detected above background in SS-15 were

calcium, sodium, lead, and zinc. Concentrations ranged from less

than two times background (calcium, lead, and zinc) to

approximately three times background (sodium).

AREA J

Surface soil samples SS-4, SS-5, SS-6, and SS-24 were located in Area J on the

east side of the upper landfill access road as shown in Figure 13C. Results of the

TCL/TAL analyses are discussed as follows:

• VOCs were not detected above the method detection limit in Area J.

Eleven semivolatile constituents were detected in the Area J surface soil

samples as discussed below:


Two semivolatile constituents (bis(2-ethylhexyl)phthalate and

diethylphthalate) were detected in surface soil sample SS-6 at 210

Mg/kg and TOîg/kg, respectively.

Bis(2-ethylhexyl)phthalate was detected in SS-5 at 23 jig/kg.

Ten constituents were detected in SS-4 with concentrations

ranging from 21 /zg/kg anthracene to 220 jig/kg fluoranthene.

• No PCB/pesticides were detected in the Area J surface soils.

• All metals in Area J surface soil samples were within the background

range with the exception of chromium (SS-4) and sodium (SS-6 & SS

24). The elevated metal concentrations were less than 2 times

background.

Recycling Area

Surface soil sample SS-22 was collected adjacent to soil boring B-22 as

illustrated on Figure 13F. Results of the analyses are as follows:

• VOCs were not detected in SS-22.

• Recycling area semivolatile analytical results identified three constituents

in SS-22 at concentrations ranging from 25 ^g/kg of fluoranthene to 79

/xg/kg of 1,4-dichlorobenzene.

• PCB/pesticide analyses detected gamma chlordane at a concentration of

0.46 ng/kg.

• All metals were detected within the background range with the exception

of sodium, which was approximately five times the background value.


Jones/Murray Property

Surface soil sample SS-20 was collected on the Jones/Murray property as shown

in Figure 4. Results of the TCL/TAL analyses are as follows:

• VOCs were not detected on the Jones/Murray property.

• Three semivolatile compounds were detected in SS-20 at concentrations

ranging from 37 ug/kg of fluoranthene to 150 /ig/kg of 1,4

dichlorobenzene.

PCB/pesticides were not detected in SS-20.

• Metals which were elevated above background concentrations included

arsenic, iron, manganese, nickel, vanadium, and zinc. All concentrations

were less than two times background.

Yahne Property

Surface soil sample SS-21 was collected from the Yahne property as shown in

Figure 4. Results of the sample are as follows:

• VOCs were below the method detection limit in SS-21.

• Semivolatile compounds were not detected on the Yahne property.

Pesticides detected in SS-21 included 4,4-DDT and 4,4-DDE at

concentrations of 3.9 fig/kg and 6.5 ngfcg, respectively.

• Metals detected above the background range in SS-21 included

aluminum, arsenic, chromium, iron, manganese, sodium, nickel, lead,

vanadium, and zinc. All concentrations were less than two times

background concentrations with the exception of lead and arsenic, which

were approximately two times the background concentration.


3.05.4 Discussion of Surface Soil Sampling Results

Surface soil sampling results provide the data required for the USEPA

Risk Assessment. In addition, analytical data correlated with the horizontal

extent of contamination as defined by the soil boring sampling program.

3.06 Soil Bonnes

Thirty-two soil borings (B-l through B-32) were installed at the Barkhamsted

Site to characterize the nature and horizontal and vertical extent of contamination in

several of the previously defined areas of investigation (Areas A, B, C, D, E, G, J, L,

Recycling Area, Previously Cleared Area #1). Soil gas surveys in Areas H and K. did

not indicate the need for soil boring installation in these areas. In addition, the

electromagnetic geophysical survey indicated that fill did not exisfln Area H. The

locations of the soil borings are illustrated on Figure 4. In addition, the location of

each soil boring within individual areas of investigation is depicted in Figures 13A

through 13F.

A total of 24 soil borings were installed within the areas of investigation based

upon existing information discussed in FSP Section 2.02.4. In accordance with the

provisions of the FSP, eight additional soil borings were installed based upon results

of the Phase 1A soil gas survey and geophysical surveys. The results of the soil gas

survey are discussed in Section 3.03 of this report. The following describes the

methods of the soil boring installations and results of the analyses performed.


3.06.1 Methods

Soil borings were completed in accordance the FSP procedures in

Appendix FSP-C. Borings were installed using hollow stem auger drilling

techniques. ASTM Method D-1586-84 was utilized to obtain continuous

samples of subsurface materials using a 2-foot long, 2-1/2 inch outside diameter,

split barrel sampler with a 140-lb hammer. Upon retrieval of the sampling

barrel, the samples were visually inspected and logged by the supervising

hydrogeologist. Soil boring logs are included in Appendix D.

Upon collection, the soil samples were divided with one portion being

placed into pre-cleaned 4-oz sample containers for VOC analysis, and a second

portion was placed into a glass container and covered with aluminum foil for

PID screening. Results of the PID screening are included on the soil boring

logs (Appendix D). The remaining sample was placed into a 1-liter amber jar.

Based upon the results of PID screening and visual differentiation between

naturally occurring and waste materials, a minimum of one sample per boring

was submitted to the laboratory for TCL/TAL analysis. A summary of soil

boring elevations, depths, sampled intervals, and first encountered ground water

is included in Table 7.

Initially, soil borings were advanced to the top of the water table. If the

water table was encountered less than 10 feet below grade, the soil borings were

advanced to a minimum depth of 10 feet or until naturally occurring soils were

encountered.

Subsequent to soil boring completion, the boreholes were backfilled with

a Portland cement/bentonite grout below the water table, and a mixture of soil


cuttings and Portland cement above the water table. Residual soil cuttings were

placed in DOT approved 55-gallon drums and staged in the borrow area in the

southern portion of the RRDD#1 property.

3.06.2 Field Modifications

Methods and locations outlined in the FSP and in the Additional Soil

Boring Technical Memorandum were modified in the field as discussed below.

• Soil borings B-31 and B-32, which were additional soil borings based

upon the soil gas survey results, were located in areas inaccessible to

drill rigs due to the steep grade of slopes in those locations. These soil

borings were advanced using a hand auger to 1 ft to 2 ft below grade.

A stainless steel spoon was used to remove a thin layer of soil which

was in contact with the hand auger, and the remaining sample was placed

into the appropriate sample containers.

• Only two of the four samples collected in boring B-29 (4 to 6 ft and 6

to 8 ft) were submitted for VOC analyses due to insufficient sample

recovery.

• Due to insufficient split spoon sample recovery in boring B-13, a second

soil boring (B-13A) was drilled adjacent to B-13 to acquire a sample.

• A sample from boring B-10 (2 to 4 ft) was submitted for VOC analysis

only due to insufficient sample recovery.

• Due to difficult drilling conditions, two soil borings were installed at the

B-17 and B-19 locations, and three soil borings were installed at the B

18 location (See Table 7).


Three soil borings (B-21, 21 A, & 2IB) were attempted in the vicinity of

boring B-21. Due to difficult drilling conditions, only soil boring B-21B

was completed successfully.

• Soil boring B-23 was not advanced to the water table due to difficult

drilling conditions. The boring was terminated at 17.4 ft after two

attempts.

3.06.3 Results

Each soil sample was shipped to Pace Laboratories, Inc in Wappingers

Falls, NY utilizing approved chain-of-custody procedures and analyzed for the

TCL/TAL parameters listed in Table 5. Analytical results for volatiles,

semivolatiles, pesticides/PCBs and inorganics are summarized in Tables 8A

through 8D, respectively. The discussion of soil boring sample results with

respect to the objectives of each soil boring are discussed below.

In addition to assessing soil boring analytical data as compared to

background data, the data were compared to levels in Table 9 which presents

soil contaminant action levels presented in the USEPA document "RCRA

Corrective Action for Solid Waste Management Units (SWMUs) at Hazardous

Waste Management Facilities".

Background Borings

Soil borings B-l and B-2 were completed to assess background

conditions at the site. Locations of the soil borings are depicted on Figures 4

and 13 A.


Background VOCs levels in B-l and B-2 were below the method

detection limit.

Bis(2-ethylhexyi)phalate was detected in B-l and B-2 at 380 ng/kg and

580 ^g/kg. respectively.

• Methoxychlor was detected in boring B-l at an estimated concentration

of 5.4 /ig/kg. which is below the quantitation limit. PCB/pesticides were

not detected in boring B-2.

• Background metal concentrations indicate consistent results for both B-l

and B-2. The concentrations provide a range in which to compare metal

concentrations detected in soils at other locations at the Barkhamsted

Site. Beryllium concentrations exceeded the USEPA action level of 0.2

mg/kg in all soil borings except B-20, B-22, and B-29. However, all

concentrations were below the laboratory quantitation limits.

The geological conditions encountered in B-l and B-2 suggest an

environment undisturbed by landfill activities. The analytical results in borings

B-l and B-2 establish a reliable base of background soil conditions with which

to compare suspected source area volatile, semivolatile, pesticide/PCB and metal

concentrations.

AREA A

Soil borings B-8, B-9, B-10, B-l l , B-l2, B-13, B-14 were installed

within and around the periphery of the suspected metal grindings waste disposal

area. In addi t ion to evaluating the vertical and horizontal extent of potential

contamination, the soil borings were used to evaluate whether the geophysical

anomalies in this area were due to subsurface conditions or surface metallic


debris. The locations of the soil borings are shown in Figure 13B. Multiple

samples were collected from borings B-9, B-10. B - l l , B-12. and B-14 as

summarized in Table 7 to better characterize the nature of the subsurface

conditions this vicinity. Results of these analyses are as follows:

• The following summarizes the highest concentrations of VOCs detected

in Area A: The compound 2-butanone was detected in boring B-9 (8.5

to 10.5 ft) at 35 /xg/kg; acetone was detected in B-12 (9 to 10 ft) at 590

/ig/kg; carbon disulfide was detected in boring B-8 (10 to 11 ft) at 29

Mg/kg: chlorobenzene was detected in B-12 (4 to 6 ft) at 500

ethylbenzene was detected in boring B-10 (2 to 4 ft) at 7600 n

toluene was detected in boring B-12 (9 to 10 ft) at 310 ^g^g

— xylenes were detected in B-10 (2 to 4 ft) at 34,000 ng/kg. voc

concentrations did not exceed USEPA action limits (Table 9).

• As indicated in Table 8B, 28 semivolatile constituents were detected in

soil borings B-8 through B-14. The highest detected concentration was

phenol at 6300 ^tg/kg in soil boring B-14 (2 to 4 ft). VOC

concentrations did not exceed USEPA action limits.

The PCB/pesticide analyses detected PCB Aroclor 1248, PCB Aroclor

1254, aldrin, alpha-chlordane, 4,4-DDD 4.4-DDE, 4,4-DDT. endnn

ketone, gamma-chlordane, endosulfan sulfate, and heptachlor epoxide.

Concentrations ranged from 1.6 Mg/kg of alpha-chlordane in B-12 (4 to

6 ft) to 6100 pg'kg of PCB Aroclor 1248 in B-12 (0 to 2 ft). PCBs (46

/xg kg of Aroclor 1254) were also detected in B-9 (8.5 to 10.5 ft);

however, results from other borings in Area A suggest these constituents


are isolated. The PCB concentration in B-12 (0 to 2 ft) exceeded the

USEPA action level of 90jxg/kg. The remaining PCB/pesticide

constituents were below the USEPA action limits.

Area A metal concentrations are discussed as follows:

Mercury was detected in boring B-10 (0 to 2 ft) at 0.72 mg/kg,

which is 18 times the quantitation limit. Mercury was also

detected in B-12 (4 to 6 ft) at 0.13 mg/kg, and B-14 (2 to 4 ft) at

0.19 mg/kg. Mercury was not detected in the background

samples.

Cadmium was detected in soil borings B-8 (10 to 11 ft), B-10 (0

to 2 ft), B-12 (9 to 10 ft), and B-14 (2 to 4 ft). The highest

detected concentration was 1.7 mg/kg, approximately two times

the quantitation limit, in boring B-10. Cadmium was not detected

in the background samples.

The highest metal concentrations were detected in soil borings B

9 and B-10. These metals included silver, aluminum, barium,

beryllium, cobalt, chromium, iron, mercury, potassium,

magnesium, manganese, sodium, nickel, lead, and antimony. The

elevated concentrations ranged from less than the quantitation

limit (antimony) to 289 times background (chromium).

The highest copper concentration in Area A was detected in

boring B-12 (9 to 10 ft) and is 484 times the background concen

trations.


Figure 14 illustrates the location of geologic cross section A-A. which is

presented as Figure 15. As indicated in the boring logs in Appendix D and

geologic cross section A - A'(Figure 15), the thickness of fill in the vicinity of

Area A ranges from 9 ft in B-l l and B-13 to 14 ft in B-8. The fill contained

refuse which is comprised of newspaper, shingles, metal pins, copper wire,

plastic, rubber tires, and styrofoam. The presence of subsurface metal wire, pins,

and shavings confirms that the geophysical anomalies discussed in the LFI

Summary Report (O'Brien & Gere, 1992) were due to subsurface ferrous

material. Based upon the results of the soil boring installations, Area A can be

confirmed as a former refuse disposal area.

The presence of metal pins and debris in the soil borings demonstrates

that the geophysical surveys in this vicinity were detecting subsurface metal.

However, results of the soil borings indicate the this metal waste is present in

discrete quantities. Analytical results indicate low concentrations of VOCs,

semivolatiles. and PCB/pesticides are present. Given the analytical results, the

proximity of Area A to the landfill, past landfill activities and the low analytical

concentrations. Area A is not a source area that should be addressed separately

from the overall landfill disposal area.

AREA B

Soil borings B-15, B-16, B-18, B-20, and B-31 (Figure 13B) were

installed around and within the suspected drum crushing area (Area B) to

evaluate if residual contamination from the drum crushing operation remained

in the soils. In addition, borings B-16 and B-18 were installed within a potential

metallic anomal> identified during the LFI geophysical surveys. Boring B-31


is an additional soil boring installed in the vicinity of Phase 1A soil gas point

LISG-106AB (Figure 13A) to aid in characterizing this suspected source area.

Table 7 summarizes the soil boring depths, sampled intervals, and depth to

ground water. Results of the TCL/TAL analyses are as follows:

• The highest detected VOCs in Area B were acetone at 160 ^g/kg in

boring B-15 (4 to 6 ft); and 2-butanone at 76 ngfkg in boring B-16 (14

to 16 ft). VOC concentrations in Area B were below the USEPA action

levels (Table 9).

• Nine semivolatile constituents were detected in Area B ranging from 28

/xg/kg of phenanthrene in B-31 (1 to 2 ft) to 220 /xg/kg of bis(2

Ethylhexyl)phthalate in B-31 (1 to 2 ft). Semivolatiles concentrations

were below the USEPA action levels (Table 9).

• All PCB/pesticide concentrations were below the quantitation limits.

• Elevated concentrations of metals were found in each soil boring, and are

discussed below:

Boring B-18 (4 to 6 ft) detected elevated concentrations of silver,

aluminum, barium, beryllium, cobalt, chromium, copper, iron.

potassium, magnesium, manganese, nickel, vanadium, and zinc.

Concentrations of the above metals were all approximately two

to three times background concentrations.

Lead was detected in boring B-31 (1 to 2 ft) at 13.8 mg/kg,

approximately three times background concentrations.

Figure 14 shows the location of geologic cross section B-B1 . As depicted

in geologic cross section B-B1 (Figure 16). the fill in Area B consists


predominantly of silt and sands intermixed with wood chips and other organic

matter (roots, branches, etc). Area B may encompass a portion of the former

stump dump which was once located in the vicinity of the recycling area. The

thickness of fil l across Area B ranges from 9 ft in B-18 to 18 ft in B-16. With

the exception of a metal fragment that was present in boring B-15 at 5.25 ft,

subsurface ferrous material was not encountered in this vicinity, indicating the

LFI geophysical anomaly was due to surface metal.

Very low levels of VOCs, semivolatiles, and PCBs/pesticides were

detected in Area B. indicating that residual contamination from the suspected

former drum crushing operation does not exist in this area. The analytical and

geological characterization of Area B indicates that Area B is not a source area

that needs to be addressed separately from the landfill disposal area.

AREA C

This area was identified during the LFI as a suspected landfill disposal

area. Soil borings B-17, B-19, and B-21 were installed within Area C (Figure

13B) to evaluate the extent of potential contamination and to determine whether

the geophysical anomalies observed during the LFI were due to subsurface

conditions or surface interference. In addition, boring B-30 is an additional soil

boring that was installed adjacent to Phase 1A soil gas point SG-11Z which

exhibited a slightly elevated soil vapor result. A summary of soil boring depths

and sampled intervals is included in Table 7. Results of the TCL/TAL analyses

are as follows:


Volatile constituents detected at the highest concentrations included

acetone at 190 /xg/kg and 2-butanone at 24 jig'kg in B-17 (13 to 15 ft).

Volatile concentrations were below the USEPA action levels (Table 9).

Twelve semivolatile constituents were detected in Area C ranging from

9 /xg/kg of fluorene in B-17 (10 to 12 ft) to 1300 /xg/kg of bis(2

ethylhexyl)phthalate in B-30 (5 to 7 ft). Semivolatile concentrations

were below the USEPA action levels (Table 9).

Pesticides detected in Area C included 4,4-DDD, 4,4-DDE. endrin

ketone. and heptachlor epoxide. The highest concentration detected was

11.0 fig/kg of 4,4-DDE in B-19 (2 to 4 ft). PCB^Pesticide

concentrations were below the USEPA action levels (Table 9).

The metal concentrations in each boring were typically one to three times

above background values.

Mercury was detected in boring B-19 (2 to 4 ft) at 0.15 mg.'kg.

Lead was detected in boring B-19 (2 to 4 ft) at 346 mglcg,

approximately eight times background concentrations.

Selenium was detected in soil borings B-17 (10 to 12 ft). B-17

(13 to 15 ft) and B-30 (5 to 7 ft). Concentrations ranged from

0.21 mg/kg (B-17, 10 to 12 ft) to 0.36 mg/kg (B-17, 13 to 15 ft).

which are all below the quantitation limit.

Thallium was detected in boring B-30 (5 to 7 ft) at 0.23 mg.'kg.

\ \h ich is below the quantitation limit.

Similar to the subsurface conditions encountered in Area B, the fill in

Area C consists of predominantly silt and sands intermixed with wood chips and


other organic matter (roots, branches, etc). This fill may be the result of the

stump dump which existed in the vicinity of the recycling area. The fill ranged

in thickness from 4 ft in B-19 to 11 ft in B-17.

Although Area C has been impacted from landfill activities, the primarily

organic nature of the fill combined with low levels of VOCs, semivolatiles,

PCB/pesticides and metals indicates that Area C is not a significant source area.

The fill encountered in Area C is limited to the eastern portion based upon soil

gas. geophysical data, and soil borings.

AREA D

This area was identified as a suspected liquid waste disposal area. Soil

boring B-7 was installed north of Area D, adjacent to LFI soil gas point LISG

78 (Figure 13C) to evaluate the potential presence of a source area in this

vicinity. A summary of soil boring sampling data are included in Table 7.

Results of the analyses are as follows:

• VOCs were not detected above the method detection limit in soil boring

B-7.

• Semivolatiles were not detected in B-7.

• PCB/pesticides were not detected above the method detection limit in

boring B-7.

• Elevated concentrations of metals, as compared to background, were

detected in B-7. These metals included silver, aluminum, arsenic,

beryllium, cobalt, chromium, iron, sodium, lead, vanadium, and zinc.

Concentrations ranged from less than two times background (cobalt) to


five times background (arsenic). However, both arsenic and cobalt were

below the quantitation limit.

All Area D detected TCL/TAL analytes were below USEPA action levels

(Table 9).

Subsurface conditions indicated from the B-7 boring log (Appendix D)

did not reveal refuse or materials originating from landfill activities or the

presence of liquid waste, indicating the limits of fill do not extend into this area.

The low analytical results indicate that Area D in the vicinity of boring B-7 is

not a source area.

AREA E

This area comprises Sedimentation Basin No. 2, and was also identified

as a possible area of waste disposal and former drum storage. Soil boring B-3

was installed in the vicinity of LFI soil gas point LISG -111, and boring B-29

was added adjacent to soil gas point SG-62DA (Figure 13C). These soil borings

were installed to evaluate a potential source area in Area E. In addition, both

soil borings were used to evaluate the potential presence of buried metallic

waste in this vicinity. As summarized in Table 7. one soil sample from B-3 and

four samples from B-29 were selected for TCL/TAL analysis. Results of these

analyses are as follows:

• VOC analytical results for Area E soil borings are discussed as follows:

VOCs were below the method detection limit in boring B-3.

Methylene chloride was detected in B-29, with the highest

concentration of 98 îg/kg detected in the 2 to 4 ft interval.


Acetone was detected in all four B-29 samples, ranging from 9

Mg^kg (6 to 8 ft) to 1200 jig/kg (2 to 4 ft).

Ethylbenzene, toluene, and xylenes was detected in B-29 between

0 ft and 6 ft. The highest concentration of toluene (260 /xg/kg)

was detected in B-29 (2-4'). Xylenes were detected between 0 ft

and 4 ft with the highest concentration of 120 jig/kg detected in

the 0 to 2 ft sample. Ethylbenzene concentrations range from 1

Mg/kg in the 4 to 6 ft sample to 67 jig/kg in the 0 to 2 ft sample.

VOC concentrations in Area E did not exceed USEPA action

levels.

Semivolatiles detected in the Area E soil borings are discussed as

follows:

Three semivolatile compounds were detected in B-3, with

concentrations ranging from 12 /xg/kg °f diethylphtalate to 55

Mg/kg of 1,4-dichlorobenzene.

Seven semivolatile constituents were detected in boring B-29

Concentrations ranged from 49 /xg/kg of 1,4-dichlorobenzene (6

to 8 ft) to 3900 /xg/kg of 2-methylphthalene (0 to 2 ft).

Semivolatile concentrations were below the USEPA action levels

(Table 10).

PCB/pesticide concentrations were below the detection limit in B-3 and

B-29.

Metal concentrations in Area E soil borings are discussed as follows:


Slightly elevated concentrations of barium and cobalt were

detected in B-3. The metal concentrations are both less than two

times background concentrations.

The bulk of metal concentrations which exceeded background in

boring B-29 were detected in the 0 to 2 ft interval and included

silver, arsenic, barium, cobalt, chromium, copper, iron,

manganese, nickel, lead, vanadium and zinc. The elevated

concentrations ranged from two times background (vanadium) to

316 times background (chromium).

As indicated from the boring logs in Appendix D, the geologic conditions

in this vicinity are similar to background conditions. However, a surficial fill

layer (0 to 2 ft) of black stained silt with ball bearings, metal pins, thread, and

wood chips is present at B-29. This fill is interbedded with gravelly sands

which grade into a black stained silt layer at 4 ft to 4.5 ft, where the water table

was encountered.

Results of the soil borings installed in Area E indicate a potential source

area does not exist in the vicinity of B-3. Buried metallic waste was

encountered in boring B-29, which is confirmed by the elevated metal

concentrations. However, the metals are predominantly at the surface, indicating

that metals have not migrated downward. Although Area E has been impacted

by landfill activities, the limits of fill should not be extended to encompass Area

E. The lou l e v e l s of VOCs, semivolatiles and PCB/pesticides associated with

the uaste indicate that this material is not a source of contaminants.


AREA F

Area F was previously identified as a stained soil area. Soil boring B-27

was an additional soil boring installed based upon the results of the Phase 1A

soil gas survey. Boring B-27 was installed in the western portion of Area F

(Figure 13D) adjacent to soil gas point SG-20D. The summary of soil boring

depths and sampled intervals is included in Table 7. Results of the TCL/TAL

analyses are as follows:

• VOCs were not detected in B-27.

Nine SVOC constituents were detected in boring B-27 (0 to 2 ft).

Concentrations ranged from 19 /ig/kg of benzo(k)fluoranthene to 530

Mg/kg of bis(2-chloroethyl) ether.

• PCB/pesticide analytical results for boring B-27 indicated that 4.4-DDE

and methoxychlor were detected at estimated concentrations below the

quantitation limit.

• Metals detected in Area F included arsenic, barium, chromium, copper,

iron, potassium, magnesium, sodium, lead, vanadium, and zinc. Elevated

concentrations ranged up to two times background (magnesium).

• TAL/TCL analytical concentrations detected in Area F did not exceed

USEPA action levels (Table 9).

The boring log in Appendix D indicates that refuse was not encountered

in B-27. indicating that the landfill disposal area limits do not extend into Area

F. Trace le\els of pesticides, semivolatiles and elevated metals are similar to

site background conditions. Based upon these results, Area F is not considered

a contaminant source area.


AREA G

This area was previously identified as the location of a metal grindings

waste cell and a drum storage and handling area. Soil borings B-26 and B-28

were installed within and adjacent to Area G in the vicinity of soil gas points

SG-33C and SG-25C, respectively. These were additional soil borings based

upon the results the Phase 1A soil gas survey. The objective of these soil

borings was to further investigate anomalous soil gas results and identify

potential contamination within Area G. Locations of these soil borings are

shown on Figure 13. Table 7 summarizes boring depths, depth to ground water,

and intervals sampled for laboratory analysis. Results of the TCL/TAL analyses

are as follows:

VOCs were not detected in B-26 and B-28.

• Semivolatile results are discussed as follows:

Bis(2-ethylhexyl)phthalate was detected in B-26 (8 to 10 ft) at

180 /zg/kg and in B-28 at 120 /xg/kg.

Di-n-butylphthalate was detected in B-26 (8 to 10 ft) at 48 /ug/kg

and in B-28 at 45 jig/kg

• PCB/pesticides were not detected in the Area G soil borings.

• Results of metal analyses are as follows:

Boring B-26 (8 to 10 ft) detected potassium and zinc at

concentrations less than two times background. All other metal

concentrations were within the established site background range.

All detected metals, with the exception of calcium, were higher

than background in boring B-28 (6 to 8 ft). The elevated


concentrations ranged from less than the quantitation limit

(selenium) to two times background (zinc).

• TCL/TAL analyte concentrations detected in Area G did not exceed


The boring logs in Appendix D indicate subsurface conditions were

similar to background with the exception that wood chips were encountered in

B-28 up to 2 ft below ground surface. No other refuse was identified in this

vicinity. These conditions, taken in conjunction with the low levels of

semivolatiles and metals along with the lack of EM-31 and magnetometer

anomalies, indicate that the portion of Area G which is not located on the

landfill is not a source area.

AREA J

Based on prior review of aerial photos, this area was identified as a

possible area of unspecified waste disposal or handling. Soil borings B-4, B-5,

and B-6 were located in Area J on the east side of the upper landfill access road

to assess the potential presence of a VOC source area. Soil boring B-25 is an

additional boring located adjacent to Phase 1A soil gas point SG-37DC (Figure

13C). A summary of soil boring depths and sampled intervals is included in

Table 7. Results of the TCL/TAL analyses completed in Area J are as follows:

• Results of VOC analyses indicate the following:

\cetone was detected in soil boring B-4 (2 to 4 ft) at 180 /ig/kg

and in boring B-25 (2 to 4 ft & 4 to 6 ft) at 4 /xg/kg and 73

^g kg. respectively.


B-25 contained BTEX constituents benzene, ethylbenzene. and

toluene. The highest detected concentration was 7 y.g'kg of

toluene in B-25 (4 to 6 ft).

• Ten semivolatile constituents were detected in the Area J soil borings.

Concentrations ranged from 7 jig/kg of chrysene in B-6 (0 to 2 ft) to 510

Atg/kg of bis(2-Ethylhexyl)phthalate in boring B-4 (2 to 4 ft).

• Results of the pesticide/PCB analyses are as follows:

PCB/pesticides were not detected in borings B-4, B-5, and B-6.

The compounds 4,4-DDD, 4,4-DDE, and 4,4-DDT were detected

in B-25 (2 to 4 ft) at estimated concentrations below the

quantitation limit.

• Results of Area J metal analysis are discussed below:

Although elevated concentrations of some metals, as compared to

background, were observed in all soil borings, boring B-4

contained the bulk of these concentrations and included silver.

aluminum, arsenic, beryllium, chromium, copper, iron.

magnesium, sodium, nickel, antimony, selenium, and vanadium.

The elevated constituents ranged from less than the quantitation

limit (antimony & selenium) to approximately six times

background for arsenic. However, the detected arsenic

concentration was less than the quantitation limit.

Lead \\as detected in B-25 (2 to 4 ft) at approximately 11 times

the site background concentration.


The TCLTAL analyte concentrations detected in Area J did not exceed


The boring logs in Appendix D indicate geologic conditions similar to

the observed background conditions. Boring B-25 exhibited fill materials

(thread and wood chips) to approximately 6 ft. Trace quantities of VOCs,

pesticides, and semivolatiles were detected throughout Area J. Based upon the

soil boring results. Area J has been impacted by landfill activities but is not

considered a source area. The limits of the landfill should not extend to

encompass Area J.

AREA H

Soil borings were not installed in Area H based upon the results of the

geophysical and soil gafsurveys (Section 3.02 and 3.03).

AREA K

Soil borings were not installed in Area K based upon the results of the

soil gas survey (Section 3.03).

AREA L

Soil borings B-23 and B-24 were installed within Area L to evaluate the

potential of a source area existing within the landfill septic field area. The

locations of the soil borings are shown on Figure 13F. A summary of soil

boring elevation, depths, and sampled intervals is presented in Table 7. Results

of TCL/TAL analyses performed on samples from Area L are as follows:

• Vo la t i l e constituents were below the method detection limit in Area L.


The semivolati le compounds di-n-butylphalate and bis(2

ethylhexy])phthalate was detected in B-24 at estimated concentrations


PCB/pesticides were not detected in Area L.

• The detected metal constituents in boring B-24 were within the

established background range.

Boring B-23 detected the following metals above the background

range: silver, aluminum, barium, beryllium, cobalt, chromium,

copper, iron, potassium, magnesium, manganese, sodium, nickel,

lead, vanadium and zinc. Each elevated metal concentration was

less than two times the background concentration.

• TCL/TAL analyte concentrations detected in Area L were below the


Logs of the soil borings in Area L indicate that background geologic

conditions exist in this vicinity. Refuse was not encountered in this area.

indicating this area should not be included within the limits of fill. Lack of

detectable VOCs, PCBs/pesticides, low levels of semivolatiles and elevated

metals indicate that Area L is not a contaminant source area.

Recycling Area

Soil borings B-21 and B-22 were installed in the vicinity of the recycling

area to evaluate potential impacts from operations in this vicinity (Figure 13F).

The summar) of soil boring depths and sampled intervals is presented in Table

7. Results of FCL TAL analyses from samples collected in this area are as

follows:


• VOC's were not detected in the recycling area.

• The semivolatile compound 1,4-Dichlorobenzene was detected in B-21

(8 to 10 ft) at 100 /ig/kg- and B-22 (8 to 10 ft) at 64 /ig/kg.

• PCB/pesticides were below the detection limit in the recycling area soil

borings.

• Recycling area metal analyses results are discussed below:

Soil boring B-21 contained the most metal constituents which

were greater than established background values. These

constituents included silver, aluminum, arsenic, barium, beryllium,

cobalt, chromium, copper, iron, magnesium, sodium, nickel, lead,

vanadium, and zinc. These elevated metals concentrations did not

exceed two times the background levels.

Antimony was detected above the site background range;

however, the concentration (2.4 mg/kg) was less than the

quantitation limit.

TCL/TAL analyte concentrations detected in the recycling area were

below the USEPA action levels (Table 9).

Refuse, including plastic and glass, was encountered within the first 2

feet below the ground surface and is the result of scattered refuse from recycling

activities, rather than disposal activities. The geology in this vicinity is similar

to background conditions, indicating the limits of the landfill disposal area do

not extend to the recycling area. Low levels of VOCs, semivolatiles and

elevated metal concentrations were detected in the recycling area. Based upon

these results, the Recycling Area is not a contaminant source area.


Previously Cleared Area #1

Soil boring B-32 was an additional soil boring installed based upon the

results of the Phase 1A soil gas survey. Soil boring B-32 was installed south

of previously cleared area #1 near soil gas point SG-49CD (Figure 13D). A

summary of the soil boring depth and sampled intervals is included in Table 7.

Results of TCL/TAL analyses performed on samples collected from this area are

as follows:

• VOCs were not detected in B-32.

• The semivolatile compounds bis(2-ethylhexyl)phthalate and di-n

butylphthalate were detected in B-32 at 130 /ig/kg and 38 iLgfag,

respectively.

• PCB/pesticides were not detected in boring B-32 above the method

detection limit.

• Metals detected above background included aluminum, beryllium, iron,

selenium, vanadium, and zinc. The concentrations ranged from less than

the quantitation limit (selenium) to less than two times background

(aluminum).

• The TCL/TAL analyte concentrations detected in previously cleared area

#1 were below the USEPA action levels.

The boring log in Appendix D indicates that refuse was not encountered

in B-32. Trace le\els of semivolatiles and elevated metals are similar to site

background condi t ions . Based upon these results, previously cleared area #1 is

not considered a source area, and shall not be considered part of the landfill

disposal area


3.07 Geotechnical Properties of Soils and Waste Materials

Geotechnical data on the properties of site soils and waste materials will be

required during preparation of the FS to evaluate stability and settlement as well as

material handling properties in conjunction with the development of remedial

alternatives. Geotechnical data sufficient to permit the evaluation of alternatives

proceed was developed during the Phase 1A Site Characterization.

A total of 32 test borings were installed during field work associated with the

Phase 1A Site Characterization. It should be noted that two of the test borings, B-31

and B-32, were installed using a hand auger and were therefore not utilized in

developing information presented in this section. Based on findings of previous

investigations and information from the test borings installed during the initial site

characterization, the stratigraphy in the vicinity of the landfill consists, from top to

bottom, of the following:

Fill;

• Ice contact deposits;

• Lodgement till;

• Bedrock;

Refuse is present above these strata in the landfill portion of the site. A more detailed

discussion of site stratigraphy is presented in Section 4.

A preliminary determination of the horizontal limits of refuse was made based

on an analysis of aerial photographs, historical records, personal interviews and site

topography. In order to more accurately evaluate the horizontal limits of the landfill.

29 test pits, or trenches, were excavated along the landfill perimeter utilizing a backhoe.

Excavation was typically initiated in clean areas and advanced toward areas suspected


of having been filled. Upon encountering the edge of fill in a given test pit. the

location was staked and the test pit backfilled. The locations of test pits installed

during the Phase 1A Site Characterization, along with the horizontal limits of the

landfill developed based on the test pit results, are shown on Figure 17. It was not

possible to excavate a test pit at location #15 due to deep snow and steep slopes. The

toe of the steep slope was visually identified as representing the edge of refuse in this

area. Based on the results of the test pits and soil borings, the total estimated area

covered by refuse is approximately 13.3 acres.

Monitoring well MW-119F was installed within the limits of the refuse at the

location shown on Figure 18. Refuse was encountered in the boring for MW-119F to

a depth between 42 and 50 feet below grade. A refuse depth between 40 and 50 feet

at this location corresponds with refuse depths which may be inferred from

interpretation of site topography. The surface of the landfill in the vicinity of MW

119F is approximately 9 feet below the highest elevation of the landfill when the

topographic survey was performed in 1990. This indicates that the greatest thickness

of refuse in this vicinity at the time of the topographic survey was on the order of 60

feet. A closure plan developed in 1992 by Fuss & O'Neill on behalf of RRDD#1 for

compliance with CTDEP regulations indicates that the top of the landfill may receive

between 5 and 10 feet more refuse prior to site closure.

Standard penetration testing was performed during installation of MW-119F and

the 32 test borings. The standard penetration number, N, is the total number of blows

of a 140-lb hammer f a l l i ng 30 inches required to drive a 2-foot sampling spoon 1 foot

after an inial 6-inch penetration. Empirical relationships have been developed relating

the value of N to structural properties of a material.


Standard penetration testing was performed periodically during installation of

MW-119F in the refuse. N values in material identified as refuse ranged from 25 to

77. The variation in N values reflect the variations in the nature of the refuse

encountered at a municipal landfill. According to the Foundation Engineering

Handbook (Winterkorn & Fang. 1975), if modeled as a soil, the N values indicate that

the refuse would behave as a medium to very dense sand with friction angles ranging

from 30° to in excess of 45°. If cohesive in nature, the refuse would behave as a very

stiff to hard clay with cohesive strengths ranging from 4,000 to 8,000 pounds per square

foot (psf).

According to the Handbook of Solid Waste Management (Wilson. 1977),

residential waste may have densities ranging from 3.3 to 27.8 pounds per cubic foot

(pcf) while industrial waste, excluding heavy metal scrap, may have densities ranging

from 1.9 to 90 pcf. Information presented in Foundation Engineering in Waste

Disposal Fills (Sowers, 1973) indicates that chopped wastes show effective strengths

similar to organic soils, with effective friction angles between 10°and 15° and cohesion

from 200 to 300 psf. Consultants working on stability of the Freshkills Landfill in

Staten Island, New York (the worlds largest landfill), have modeled refuse as having

unit weights ranging from 53 to 86 pounds per cubic foot (pcf), friction angles from 27°

to 38° and cohesion on the order of 300 psf (IT Corporation and others, 1992). The

range of values which have been reported for geotechnical parameters associated with

refuse reflect the heterogenous nature of municipal waste. In light of this discussion

and the nature of \\aste deposited at the Barkhamsted Site, it is proposed that

parameters similar to those ultimately selected for use in the Freshkills study be utilized


in modelling which will be performed to evaluate remedial alternatives. This approach

results in using a unit weight of 70 pcf, a friction angle of 33°, and a cohesion of 300

psf. These values are conservatively within the ranges of values indicated by field test

results and reported in the literature.

As previously discussed 30 test borings from which geotechnical data can be

developed were installed at the Barkhamsted Site. Of these, 25 encountered fill

composed primarily of disturbed silty and sandy soil, with some extraneous material

such as wood chips, glass, plastic, rubber, paper, styrofoam, cans, brick fragments, and

copper wire. Where encountered, fill thickness ranged from 0.5 to 18 feet. Of the 82

standard penetration tests performed in material classified as fill, N values ranged from

2 to 182 with an average value of approximately 52, and a median value of

approximately 41. The analysis of N values indicate that the fill should be evaluated

as a dense, cohesionless soil. The median N value is indicative of a friction angle

ranging from approximately 38° to 43° according to information presented in

Foundation Engineering Handbook (Winterkorn & Fang, 1975). It is proposed that a

value of 38° be used for evaluation of remedial options. Information presented in So/7

Mechanics (Lambe & Whitman, 1969) indicates that dry unit weights for silty sand

typically range from 87 pcf to 127 pcf. These values will increase as the moisture

content of the material increases. Test boring logs indicate that the fill ranges from dry

to moist. Given the dense nature of the fill indicated by the N values and the presence

of moisture in some of the fill, a unit weight of 120 pcf is appropriate for use in

analyses to be performed in evaluating remedial alternatives.

Previous investigations and test borings installed for this investigation indicate

that the site is underlain by ice contact deposits which are in turn underlain by


lodgement till. From an engineering perspective, these materials may be considered as

a single unit. Till was encountered in 28 of the 30 test borings installed during this

investigation from which geotechnical data can be derived, as well as at the bottom of

the boring for MW-119F installed through the refuse. In these borings, a total of 115

standard penetration tests were performed with N values ranging from 4 to 205. The

average and median N value for the till is approximately 95. A total of nine samples

of the till were tested for the following parameters:

• Natural moisture content:

• Bulk (natural) soil density (unit weight);

Porosity: and

• Specific gravity.

These samples, in addition to other samples as described in Section 3.06, were also

tested for mechanical grain size analyses. The results of the analyses of these nine

samples are presented in Appendix C.

Natural moisture contents ranged from 9.1% to 32.1% with an average value of

15%. Unit weights ranged from 84.8 pcf to 125.6 pcf with an average value of 113.5

pcf. Values for porosity ranged from 24.8 to 48 with an average value of 33. Specific

gravities ranged from 2.61 to 2.73 with an average value of 2.7. The grain size

analyses performed on samples for which the other laboratory tests were performed

indicated between 27.3% and 77.5% passing a number 200 sieve with an average value

for these nine samples of 39% passing the number 200 sieve.

The values for the tested parameters are all within typical ranges which might

be expected for t i l l . The unit weight of 84.8 pcf is on the low end of the normal range

and the porosity of 48 is on the high end of the normal range. These values occurred


in the same sample which also had the highest natural moisture content. This

information indicates an anomalous condition in the tested sample. Based on the results

of the standard penetration testing and the results of the laboratory analyses, it is

recommended that the average values of parameters for which laboratory tests were

performed be utilized for subsequent evaluations.

According to information presented in the Foundation Engineering Handbook

(Winterkom & Fang. 1975), glacial till is often assumed to have a presumptive bearing

capacity between 8,000 to 24.000 pcf. The same reference indicates that N values in

excess of approximately 50 correlate with a cohesive strength of 8,000 psf in a clay

soil. In light of the high percentage of fines and the high N values, it is recommended

that the glacial till be modeled as a cohesive soil with a cohesive strength of 8,000 psf.

The final component of site stratigraphy is schist bedrock which is encountered

at depths ranging from 9 feet to 50 feet below grade. Given the high strength of

materials overlying bedrock, any geotechnical properties of bedrock required for

evaluation of remedial alternatives will be minimal and can be reasonably assumed from

literature values.

It should be noted that the approved FSP for the Barkhamsted Site called for the

monitoring of landfill settlement. This was to be accomplished by installing eight

settlement plates and surveying their elevations quarterly. During conduct of field work

associated with other elements of the FSP, it was observed that the area proposed for

installation of the settlement plates is currently receiving waste. As previously

discussed, the 1992 Closure Plan for the site indicates that the area proposed for the

installation of settlement plates will receive between 5 and 10 feet of additional refuse

prior to site closure.


In a letter to the USEPA dated February 10, 1993. O'Brien & Gere

recommended that, in light of continuing operations at the landfill, installation of

settlement plates be deleted from work to be performed in connection with the Phase

1A Remedial Investigation/Feasibility Study. O'Brien & Gere further proposed that

information presented in the literature be used for evaluation of likely landfill settlement

rates for purposes of evaluating remedial alternatives during the Feasibility Study. It

was also proposed that, if necessary, field data could subsequently be developed for

purposes of final design. By copy of a letter dated March 16, 1993, the USEPA

concurred that sufficient information may be available in the literature to evaluate likely

landfill settlement rates during the FS. However, in accordance with requirements in

that letter, a plan and schedule for obtaining site specific data for purposes of design

is to be developed by O'Brien & Gere and implemented subsequent to approval by

USEPA.


SECTION 4 HYDROGEOLOGIC INVESTIGATIONS

4.01 General

The objectives of the subsurface hydrogeologic investigations at the Barkhamsted

Site were to characterize the site hydrogeologic conditions, evaluate the potential for

contaminants from the site to enter the ground water system and migrate to potential

receptors, and to develop information to aid in the selection of appropriate remedial

alternatives.

The migration of contaminants in ground water to potential receptors is largely

controlled by the site hydrogeologic conditions. The Phase 1A Site Characterization

hydrogeologic investigations focused on characterization of the overburden and bedrock,

and assessed the hydraulic relationship between the various water bearing zones and

surface water bodies in the vicinity of the Barkhamsted Site. The P h a s e 1A

hydrogeologic investigations were designed to utilize and supplement the hydrogeologic

data collected by Fuss & O'Neill, Inc. in 1991 and summarized in the LFI Summary

Report.

4.02 Hvdrogeological Field Investigations

The objective of the monitoring well installation program was to characterize the

horizontal and vertical extent of ground water contamination and to evaluate the site

hydrogeology. The monitoring well network was also used to provide data for

estimating the volume of ground water in contact with the landfill material.


4.02.1 Ground Water Monitoring Well Installations

A total of seven overburden monitoring wells and 15 bedrock monitoring

wells were installed as part of the Phase 1A Site Characterization to supplement

the 31 existing ground water monitoring wells. A summary of newly installed

and existing monitoring well specifications is included in Table 4. The locations

of all site monitoring wells are shown in Figure 18. The monitoring well logs

are included in Appendix D.

As described in the FSP, the monitoring well locations were selected

based on existing hydrogeologic ground water quality data, and were designed

to screen various water bearing zones. The wells designated as F (fill), S

(overburden), B (shallow bedrock), I (intermediate bedrock), and D (deep

bedrock) evaluate ground water quality at various depths. The rationale for each

monitoring well location is provided in the FSP.

Methods

Overburden Monitoring Wells

Six overburden monitoring wells and one fill material monitoring well

(MW-113S through MW-118S, and MW-119F) were installed using 4 1/4 inch

inside diameter (I.D.) hollow stem augers (HSA) in accordance with FSP

Appendix FSP-F. During drilling, soil samples were collected continuously at

2-foot intervals utilizing 2-inch diameter split spoon sampling techniques in

accordance with ASTM Method D-l586-84.

Each overburden well was constructed with a 2-inch I.D. schedule 40

PVC well casing which was joined water tight using flush threads to a 10-ft


length of 2-inch I.D. Schedule 40 PVC 0.010-inch slotted well screen with a

PVC plug at the base. The well casing extended from the screened interval to

2 ft to 3 ft above the ground surface. The annular space between the well

screen and the borehole was filled with washed silica sand compatible with a

0.010-inch slot well screen extending from the base of the hole to a minimum

of 1 foot above the well screen. A bentonite pellet seal was installed above the

filter pack with a minimum thickness of 2 ft. Following installation of the

bentonite seal, a portland cement/bentonite grout was placed in the annular space

between the outside of the well casing and the borehole wall above the bentonite

seal. Each well was finished with a locking 6-inch protective steel casing which

was installed over the PVC casing.

Bedrock Monitoring Wells

Bedrock monitoring wells were installed using conventional air rotary

drilling techniques in accordance with the procedures presented in FSP

Appendix FSP-F. Each bedrock monitoring well was installed by initially

advancing a 10-inch diameter temporary casing to the top of bedrock. A 10

inch diameter borehole was then advanced through the temporary steel casing

approximately 5 ft into competent rock. A permanent 6-inch diameter, schedule

20, new carbon steel casing was installed through the 10-inch temporary casing

into the bedrock borehole, and was extended approximately 2 ft above ground

surface. The 6-inch steel casings were grouted in place with a Portland

cement/bentonite grout mixture as the temporary 10-inch steel casings were


removed. The grout mixture was allowed to cure a minimum of 12-hours prior

to proceeding with subsequent stages of well installations.

The 6-inch diameter borehole was then completed to a depth which either

produced ground water flow rates of at least 0.1 gallons per minute (gpm), or

in selected well nests (MW-101, MW-104, MW-106, MW-110, MW-111, and

MW-113), based upon the results of packer testing as discussed in Section

4.02.4.

During the drilling of fhe monitoring wells, formation samples were

collected at 5-foot intervals and at each formation change using a wire strainer.

Descriptions of each bedrock borehole are included in the boring logs in

Appendix D.

Bedrock ground water monitoring wells were constructed of 2-inch I.D.,

threaded, flush-joint, schedule 40 PVC well casing attached to 10-ft sections of

2-inch I.D., 0.010-inch slot size, schedule 40 PVC well screen. A washed silica

sandpack compatible with a 0.010-inch slot screen was installed from the bottom

of the borehole to at least 2 ft above the well screen. A bentonite pellet seal

with minimum thickness of 2 ft was installed on top of the sandpack. The

remainder of the annular space above the bentonite seal was filled with a

Portland cement/bentonite grout mixture by pumping the mix through a tremie

line. Each permanent 6-inch casing was fitted with a locking cover to complete

the well installations. As-built construction details of the bedrock monitoring

wells are included in Appendix D.


Field Modifications

The following field modifications resulted in deviations from procedures

presented in the approved FSP.

• The screened interval in monitoring well MW-113S does not extend

above the water table. Difficulty in identifying saturated conditions in

this vicinity resulted in the well screen being placed at the top of

bedrock, below the top of the water table.

• During installation of MW-113I and MW-106B, the temporary 10-inch

casings could not be retrieved from the subsurface, requiring that they be

left in place and cut flush with the ground surface, leaving the wells

triple-cased.

• An 8-inch temporary casing was installed to the top of bedrock during

the installation of MW-106B. This was due to the inability to advance

or retrieve the temporary 10-inch casing at this location as a result of

subsurface conditions.

Bedrock monitoring wells MW-111I, MW-117B, and MW-118B were

installed using a combination of mud rotary techniques and conventional

air rotary techniques due to difficult subsurface drilling conditions

consisting of cobbles and boulders, and the inability to maintain an open

borehole during overburden drilling. Mud rotary techniques were utilized

during the overburden drilling to install the 10-inch temporary casing to

the top of bedrock. Subsequent to installing the 10-inch temporary

casing, conventional air rotary techniques were utilized to complete


bedrock monitoring well installation. This modification was discussed

with and subsequently agreed to by the USEPA.

4.02.2 Monitoring Well Development

The overburden and bedrock monitoring wells were developed

following installation to remove fine grained sediments that may have

settled around the well screen during the drilling of each well so that the

screen is transmitting representative portions of the ground water.

Development of the overburden wells was completed by hand

bailing with stainless steel bailers. A length of new polypropylene rope

was utilized at each overburden well location, and the bailers were

decontaminated between overburden well locations in accordance with

the protocol presented in FSP Appendix FSP-D. Development consisted

of lowering the bailer to the bottom of each overburden well, gently

raising and lowering the bailer to agitate sediments, and then retrieving

the bailer to remove the sediment. Development of the overburden wells

ceased after a minimum of 2 hours, the well yielded relatively sediment

free water, and exhibited consistent field pH and specific conductance

measurements. Development water was contained and managed in

accordance with the protocol presented in FSP Appendix FSP-A.

The bedrock ground water monitoring wells were developed with

a Grundfos Redi-Flo 2 submersible pump (a Brainard-Kilman hand pump

was utilized on MW-113B and MW-117B due to a malfunction of the

Grundfos). During development, field measurements of pH, specific


conductance (îS). and temperature (°C) were recorded periodically.

Bedrock well development ceased after a minimum of 2 hours the wells

yielded relatively sediment free water, and exhibited consistent of pH,

specific conductance, and temperature measurements. Development

water was containerized and managed in accordance with the FSP

Appendix FSP-A.

4.02.3 Hydraulic Conductivity Testing

Methods

In situ hydraulic conductivity tests were performed on the newly installed

overburden and bedrock wells to estimate the horizontal hydraulic conductivity

in the overburden and bedrock materials in accordance with procedures

presented in FSP Appendix FSP-I. The tests were conducted by first inserting

a pressure transducer (AquiStar DL4A-16A, Instrumentation Northwest, Inc.)

into the well and then performing a rising head and/or a falling head hydraulic

conductivity test by inserting a solid PVC rod into the well. The transducer

system was used to collect recovery data at pre-programmed time intervals at all

newly installed monitoring wells except MW-113I, 113D, 115B, and 116B.

Hydraulic conductivity data were collected at these wells by hand using an

electronic water level probe, due to the protracted recovery times in these wells.

The slug test data collected from the overburden wells was interpreted

using the Bouwer and Rice method (Bouwer, 1989) for unconfined aquifers.

The slug test data collected from the bedrock wells was reduced using the

Cooper method (Cooper and others 1967). Both methods are contained in the


AQTESOLV™ Aquifer Test Solver program which is a computer program

designed for the reduction of in situ hydraulic conductivity tests Version 10

Documentation (Geraghty and Miller, Inc., 1988, 1989). Results of the

hydraulic conductivity test results are included on Table 4, and field pressure

transducer data and AQTESOLV plots are contained in Appendix E.

Results

Hydraulic conductivity data for each well is listed in Table 4 and

summarized as follows:

Hydraulic Conductivities

Overburden

l . l x l O ' 1 ft/day (MW-101S) to 7.46 ft/day (MW-111S)

Shallow Bedrock

3.3 x 10° ft/day (MW-118B) to 34.87 ft/day (MW-111B)

Intermediate Bedrock

1.62 X 10° ft/day (MW-113I) to 43.06 ft/day (MW-111I)

Deep Bedrock

2.01 x 10° ft/day

Hydraulic conductivity tests could not be performed on MW-101D.

Water between the 6-inch steel protective casing and the 2-inch PVC well casing

had frozen, thus causing the 2-inch PVC casing to buckle in a manner as not to

allow slugs or bailers to be inserted into the well. The permanence of this

damage will be assessed during the second round of ground water sampling, and

the well will be repaired as necessary.


4.02.4 Packer Testing

Packer tests were conducted in the bedrock boreholes at monitoring wells

MW-101D, 1041, 1061, 1101. 1111, and 113D as part of the Phase 1A Site

Characterization to evaluate flow in the fractured bedrock at the landfill site as

it relates to the potential for contaminant migration. In addition, packer tests

were performed to assist in evaluating the screened intervals for the shallower

bedrock monitoring wells at those locations.

Methods

Following the completion of the bedrock borehole, each borehole was

flushed with clean water to remove cuttings, and the depth of each borehole was

measured to check for borehole wall collapse. The packer testing equipment

(consisting of two inflatable rubber packers separated by a 2-inch diameter

perforated pipe) was lowered into the borehole. Upon reaching the interval to

be tested, the packers were inflated to approximately 500 psi through a high

pressure hose attached to a cylinder of compressed nitrogen. To monitor the

effectiveness of the seal, an in-line pressure gauge was utilized to monitor the

packer inflation pressure. Figure 19 shows a schematic of the packer testing

equipment. In addition, an appropriate seal of the test interval was confirmed

when the pressure in the inflated packers supported the weight of the entire

packer string.

Once the packer equipment was set within a borehole, a small diameter

submersible (Redi-Flo 2) pump was lowered to the bottom of the packer string

. and the interval was purged. Water level measurements were monitored above

the packed interval to check for potential leakage into the packed interval. If


a minimum 0.1 gpm continuous flow rate could be achieved during the purging

process, this flow rate was noted and a minimum of one test interval volume

was removed from the packed interval. When continuous flow rates could not

be maintained, due to the interval being pumped dry, the water level in the

packed interval was allowed to recover for 15 minutes. After the 15-minute

recovery period, the interval was purged again and the volume of water

recovered was measured. An estimated flow rate was calculated from the test

interval by dividing the volume of water recovered by the 15-minute recovery

period.

If a continuous or estimated flow rate of the test interval was greater than

0.1 gpm. then the test interval was sampled for VOC headspace analysis using

either a stainless steel bailer or pump at a flow rate less than 100 ml/min.

Samples were collected in 40-ml glass vials and analyzed using an on-site gas

chromatograph (GC) as discussed in Section 4.02.5. If the flow was calculated

to be less than 0.1 gpm, the test interval was not sampled, the packers were

deflated, and a new interval was tested. A summary of each packer tested

interval, with respect to estimated flow rates and VOC headspace analysis, is

included in Table 10.


4.02.4.1 Field Modifications

• Water levels within the packer string could not be monitored due

to the pump discharge hose and nitrogen supply lines preventing

the insertion of a water level probe within the 2-inch diameter

packer pipe.

• Subsequent to purging, the water levels in the packer string were

not monitored due to the pump continually getting caught on the

packer string couplings. By the time the pump was removed the

water level had recovered.

Due to the highly fractured nature of the bedrock in the vicinity

of the Barkhamsted Site, water levels above the packer string

during purging were often observed dropping, indicating leakage

into the packed interval through interconnected fractures. The

leakage was estimated by converting feet of observed drawdown

above the packer string to volume of water (gallons). This

leakage volume was subtracted from the total volume pumped

from the packed interval. The resulting difference was divided by

the time required to pump the packed interval, which gives an

approximate flow rate of the packed interval. The intervals which

exhibited leakage are noted in Table 10.

• VOC headspace samples were collected from the pump discharge

hose during packer testing of MW-101D intervals 219 ft to 229

ft, 209 ft to 219 ft, and 199 ft to 209 ft at a flow greater than 100


ml/min. After subsequent discussions with USEPA oversight

contractor personnel, the 100 ml/min standard was adopted.

• Initially, packer testing was initiated in 25-foot increments (MW

113D) in accordance with the FSP protocol. Subsequent packer

tests were performed in 10-foot intervals (MW-101D, MW-106I)

to more accurately define discrete flow zones. However, due to

the high incidence of packer leakage, packer testing was

performed at20-ft intervals (MW-104I, MW-1101, and MW-1 111)

to allow for timely installation of monitoring wells.

4.02.5 Packer Testing/Headspace Analysis

The objective of the packer test headspace screening was to evaluate

VOC concentrations at discrete depth intervals in order to select the optimal

screen interval for the bedrock wells. This objective was pursued by collecting

a series of ground water samples from packer tested intervals in six on-site

monitoring wells, and analyzing the headspace using a Photovac 10S70 portable

gas chromatograph (GC).

Ground Water Sample Collection

Ground water headspace samples were collected from packer tested

intervals using either a stainless steel bailer or from the pump discharge hose as

discussed in Section 4.02.4. The samples were then transferred to two 40 ml

vials equipped with teflon septa, headspace free, placed on ice, and transported

to the field laboratory. The two 40 ml vials were placed in a constant


temperature bath at 40° Celsius for 15 minutes. A syringe needle was placed

through the septa of one vial to act as a vent while 10 ml of the water sample

was removed by a 10 ml glass syringe. The vial was shaken thoroughly for 1

minute, and the sample was allowed to reach thermal and phase equilibrium by

standing in the constant temperature bath for an additional 10 minutes. A

precise 100 /x aliquot of headspace was then extracted from the vial using a gas-

tight syringe and injected into the Photovac GC. The second vial served as a

duplicate should re-analysis be required.

Results

A total of 24 ground water samples were collected for GC headspace

analysis from the packer tested intervals of six monitoring wells (MW-101D,

MW-104I, MW-106I, MW-110I, MW-111I, and MW-113D) and are

summarized in Table 10. Total VOC concentrations 'in monitoring well

headspace samples ranged from non-detect (<0.025 ppm) to 20.6 ppm. The

predominant calibrant compound detected in the ground water headspace

samples was toluene. Other calibrant compounds detected included vinyl

chloride (one sample), MEK (one sample), benzene, MIBK, toluene, and xylene.

Discussion of Packer Testing Results

The objective of packer testing was to evaluate flow in the fractured

bedrock at the landfill site as it relates to the potential for contaminant

migration. This objective was not fully achieved due to the highly fractured

nature of bedrock in the vicinity of the Barkhamsted Site, which resulted in


routine leakage of ground water into packer tested intervals. This leakage

compromised the integrity of ground water headspace samples and did not allow

for precise measurement of flow rates within a packer tested interval. It is

concluded that the headspace analysis is not an appropriate technique for

evaluating potential contaminant migration at this site.

Packer testing was useful in evaluating relative flow rates within the

borehole. Despite the routine leakage into a packer tested interval, the leakage

was quantified, so as to evaluate which packer tested zone yielded the highest

flow rate. Subsequently, screened intervals could be selected to be consistent

with higher flow zones. However, flow rates can also be estimated using yield

tests while drilling a monitoring well, which would reduce costs and time delays

for well installation.

4.03 Physical Characteristics of the Site

4.03.1 Regional Geology

The landfill study area is located in the southwestern portion of the New

Hartford, Northwestern Connecticut quadrangle (Figure 1). The surficial and

bedrock geology has been mapped by Schnabel (1973, 1975). Unconsolidated

deposits cover approximately 95 percent of the New Hartford quadrangle with

thicknesses ranging from 0 to 90 feet (Schnabel, 1975). The greatest volume of

the Pleistocene and Holocene surficial materials are composed of glacial

deposits, with lesser quantities of stratified drift, stream terrace deposits, swamp

deposits, and alluvium. Two types of glacial contact deposits are present locally

(Schnabel. 1975). A compact silt and clay matrix lodgement till was deposited


on the bedrock surface during glacial advance. The lodgement till is overlain

by a less dense, silt to boulder matrix which was deposited during glacial retreat.

Bedrock in the vicinity of the site is mapped as the Moretown Formation

(Middle Ordovician) consisting of fine-grained medium to medium-light-gray

quartz-plagioclase-biotite-(muscovite)-(garnet) schist containing thin beds of

fine-grained light green and black hornblende-epidote-plagioclase amphibolite

(Schnabel, 1975). Bedrock is not exposed at the site, however, a large bedrock

outcrop ridge runs in a north-south direction along the western side of the

Unnamed Brook.

Surficial Site Geology

Site geology has been interpreted based on samples collected from soil

borings, overburden monitoring wells and bedrock monitoring wells, as well as

available published literature. Geologic logs containing specific sample depths

and descriptions are contained in Appendix D.

During implementation of the Phase 1A RI, four surficial units,

consisting of fill material, glacial outwash and/or fluvial deposits, ice contact

deposits, and lodgement till were encountered within the landfill study area.

Figure 14 is a cross-section index map. Figures 15 and 16 are geologic cross-

sections illustrating the surficial geology in potential disposal Area A (A-A') and

Areas B and C (B-B'), respectively. The description and extent of each

encountered surficial deposit are as follows:

• The fill material, as described from soil boring samples, is mainly

composed of landfill debris (metals, plastics, wood products, etc.) as


shown in geologic cross sections A-A1 (Figure 15) and B-B' (Figure 16).

The areal extent of fill material is limited to the landfill (Figure 17)

disposal area, as has been shown by a series of test pits excavated around

the landfill and discussed in Section 3.07.

• Glacial outwash and/or fluvial deposits consisting of stratified sands, silts

and gravel are concentrated along the Farmington River floodplain.

These deposits were encountered in MW-117S and MW-118S and range

in thickness from 10 ft to 63 ft, respectively.

• Poorly sorted, moderately dense to very dense sand, silt, cobble and

gravel ice contact deposits were encountered across the majority of the

site. This unit appears to thicken northward toward the Farmington

River valley as shown in geologic cross section C-C1 (Figure 20). The

ice contract deposits overlies bedrock at areas north and east of a line

connecting the MW-110, MW-1. and MW-106 well nests (Fuss &

O'Neill, 1991b).

A poorly sorted, dense, silt and clay matrix lodgement till was

encountered in soil samples in a limited area at the site. This till unit

was encountered at soil borings B-8 (Figure 15) through B-14 at depths

ranging from 8.5 feet at B-l 1 to 14 feet at B-8. It was also encountered

in MW-112B, MW-113S, and MW-107B at depths ranging from

approximately 10 feet at MW-107B to approximately 20 feet at MW

112B (Fuss & O'Neill, 1991). The lodgement till overlies the bedrock

in the southern portion of the site, extending northward to the MW-106

well nest (Figures 20 and 21). In addition, the lodgement till was


encountered beneath the fill in MW-119F, suggesting lodgement till

underlies the landfill disposal area (Figure 20). The northward extent of

the lodgement till unit appears to end at a line connecting the MW-110

and MW-1 nests where ice contact deposits were encountered overlying

bedrock (Fuss & O'Neill, 1991b).

4.03.2 Site Bedrock Geology

Fifteen bedrock monitoring wells were installed at the site at depths

varying from approximately 67 feet below ground surface at MW-113B to

approximately 250 feet below ground surface at MW-113D. The bedrock wells

were installed to screen the shallow, intermediate, and deep bedrock zones.

Depth to bedrock varied across the site from approximately 10 feet below

ground surface at MW-117B to approximately 63 feet below ground surface at

MW-118B.

Bedrock cuttings were collected and described at each drilling location.

Bedrock encountered at the Barkhamsted Site is a pegmatite intruded micaceous

schist. During drilling, the bedrock formation was described as soft to

moderately hard. The softness of the rock made distinctions between the

weathered and competent bedrock stratums not easily definable. In addition,

bedrock softness made identification of fracture zones difficult during drilling.

However, as indicated from packer testing results (Section 4.02.4), bedrock was

moderately to highly fractured.

Geologic cross section C-C? (Figure 20) is oriented from south of the

landfill disposal area across the site to the northeast to the MW-111 nest on the


Farmington River floodplain, as shown in Figure 14. As shown from the cross

section and the boring logs, weathered schist was more thick to the south of the

site and ranged from approximately 6 ft in MW-111 to 75 ft in MW-113. The

bedrock surface across the site dips to the north-northeast which is supported by

bedrock elevations estimated from resistivity surveys as shown in Figure 10.

4.03.3 Regional Hvdrogeologv

The Barkhamsted Site is situated along the west branch of the

Farmington River Basin. The Farmington River Basin is located in north central

Connecticut. The present regional topography is the result of Pleistocene Age

glaciation. In general, the regional ground water supply is located in overburden

deposits and the bedrock (Handman et al, 1986). However, bedrock ground

water was the predominant ground water supply in the vicinity of the

Barkhamsted Site as discussed in Section 4.05.

The overburden aquifer is comprised of either glacial contact deposits

(till), glacial outwash deposits (stratified drift), or alluvial and/or fluvial deposits.

The glacial contact deposits are divided into either ablation or lodgement t i l l .

These till units are relatively thin and are poor aquifers. Hand dug wells in the

vicinity of the Barkhamsted Site are typically screened within till units.

Glacial outwash deposits are sediments which have been transported and

deposited by glacial meltwater into interbedded gravel, sand, silt and clay

deposits. Alluvial and/or fluvial deposition is similar to glacial outwash deposits

and is an ongoing process today. Glacial outwash and alluvium fill the valleys

and lowlands, and covers approximately 22% of the Farmington River Basin


(Handman et al, 1986). Glacial outwash deposits are the most productive of

overburden aquifers averaging 100 ft in thickness in the Farmington River

Basin. The median yield from this overburden aquifer is 141 gpm with yields

ranging from 4 to 1400 gpm (Handman et al, 1986). However, results of the

ground water user survey (Section 4.05) indicate that ground water supply wells

in the vicinity of the Barkhamsted Site are not screened in this unit.

The bedrock which underlies the Farmington River Basin is a

metamorphic schist as discussed in Section 4.03.1. Bedrock ground water is a

source of water supply for home owners in the vicinity of the Barkhamsted Site.

Ground water storage and movement in bedrock generally occurs in fractures.

Well yields in the bedrock aquifer in the Farmington River Basin range from 0.1

to 200 gpm, with a median yield of 5 gpm (Handman et al, 1986).

4.03.4 Site Hydrogeologv

Two complete rounds of ground water and surface water elevations were

completed on December 28, 1992 and January 26, 1993 as presented in Table

4. In addition, stream water gauge readings are included in Table 11. Ground

water elevations recorded from the latter round are discussed in this section.

An estimation of ground water transmitting capacity is presented for each

water bearing zone. A range of linear ground water flow velocities can be

approximated using the following equation:

DRAFT . 102 April 29, 1993

Darcv's Law

V=Ki/n

Where:

v = velocity (ft/day)

K = hydraulic conductivity (ft/day)

i = hydraulic gradient (ft/ft)

n = average porosity

The following assumptions were made in applying Darcy's Law:

• The average porosity for the overburden (clay to gravel) is 30%

(Todd, 1980) and porosity for the bedrock was derived from the

apparent porosity log which was performed on the monitoring

well MW-4R-1+2 borehole as described in the LFI Summary

Report. The apparent porosities with respect to elevation were

assumed to be constant across the site. Table 12 lists screened

elevations and porosities for that elevation encountered in V1W

4R-1+2.

• Bedrock behaves as a porous media due to its moderate to highly

fractured nature.

Overburden Zone

Depth to water in the overburden wells varied from 3 ft at S-3 to 18.9

ft at MW-105S. A ground water elevation map (Figure 22) was constructed for

the overburden ground water flow from data collected on January 26, 1993.

Ground water flow in the overburden is to the north in the vicinity of the

landfill disposal area. The overburden ground water flow is diverted to the


northeast adjacent to the Unnamed Brook and flows off the RRDD#1 property,

north of the landfill disposal area. Ground water within the overburden flows

under hydraulic gradients ranging from 0.009 ft/ft to 0.16 ft/ft and with an

appropriate velocity of 3.1x10"2 ft/day to 2.36 x 10"' ft/day.

Shallow Bedrock Zone

Depth to water in the shallow bedrock wells varied from 1.35 ft at MW

5B to 35.02 ft at MW-115B. A ground water elevation map (Figure 23) was

constructed for the shallow bedrock ground water flow from data collected on

January 26, 1993. Ground water flow in the shallow bedrock in the vicinity of

the landfill disposal area is to the north. Similar to overburden flow, bedrock

ground water flow diverts to the northeast as it flows from RRDD#1 property.

Shallow bedrock ground water flows under hydraulic gradients ranging from

0.008 ft/ft to 0.20 ft/ft and with an approximate velocity of 2.21 x 10° ft'day to

13.99 ft/day.

Intermediate Bedrock Zone

Depth to water in the intermediate bedrock wells varied from 1.94 feet

at MW-110I to 18.88 feet at MW-4R-2. A ground water elevation map (Figure

24) was developed from the intermediate bedrock ground water flow from data

collected on January 26, 1993. Ground water flow in the intermediate bedrock

is to the north-northeast under hydraulic gradients ranging from 0.032 ft/ft to

0.12 ft/ft. The approximate ground water velocity from the intermediate bedrock

depths range from 1.56 x 10° ft/day to 43.06 ft/day.


Deep Bedrock Zone

Depth to water in the deep bedrock wells varied from approximately 2

feet above ground surface at MW-113D to 18.62 feet at MW-4R-1. A ground

water elevation map (Figure 25) was constructed for the deep bedrock ground

water flow from data collected on January 26, 1993. Ground water flow in the

deep bedrock is to the north under a relatively uniform hydraulic gradient of

approximately 0.085 ft/ft. The estimated ground water velocity in the deep

bedrock zone is 3.42 x 10° ft/day.

4.03.5 Conceptual Site Hvdrogeologic Model

The conceptual hydrogeologic model for the Barkhamsted Site was

developed based upon the evaluation of packer tests, hydraulic conductivity

tests, vertical gradients, and ground water elevations. Figures 26 and 27 present

semi quantitative flow nets which illustrate the hydraulic relationship between

the various geologic zones and surface water bodies at the Barkhamsted Site.

Cross section E-E' (Figure 26) shows the hydrogeologic conditions from

the vicinity of the landfill disposal area across the Unnamed Brook, north of the

RRDD#1 property line to MW-104 well nest (Figure 14). Vertical gradient data

are presented in Table 13. As indicated in Figure 26, the overburden and

bedrock aquifer systems act as an interconnected hydraulic unit. Downward

vertical gradients ranging from 0.005 ft/ft to 1.68 ft/ft exist between the

overburden and bedrock in the vicinity and south of the landfill disposal area.

The highest downward vertical gradient exists in the MW-110 nest, located


along the northern toe of the landfill disposal area. This suggests contaminated

ground water may move downward as well as northward in this vicinity.

Overburden to bedrock vertical gradients north of the landfill disposal

area are upward ranging from 0.016 ft/ft to 0.083 ft/ft. These data suggest that

ground water flows upward as it flows toward the Unnamed Brook north of the

site. Ground water elevation and vertical gradient data indicate that the

overburden is hydraulically connected to the Unnamed Brook (Figure 26).

Although ground water within the bedrock zones has an upward potential north

of the landfill disposal area, flow from the deeper zones may not be

hydraulically connected to the Unnamed Brook (Figure 26).

As indicated from the ground water elevation maps, ground water flow

converges and is diverted to the northeast in the vicinity of the Unnamed Brook

north of the landfill. This ground water diversion is caused by the topographic

high which exists northwest of the site (Figure 1). This is further evidenced by

the ground water quality data in MW-104 nest which indicates that the

contaminant plume does extend to this location. Although bedrock ground water

may not be hydraulically connected to the Unnamed Brook north of the landfill.

the diversion of ground water flow to the northeast indicates contaminants from

the Barkhamsted Site do not extend beyond the Unnamed Brook in this vicinity.

Cross section F-F' (Figure 27) shows the hydrogeologic conditions in the

vicinity of the landfill disposal area, across the site, to the northeast in the

direction of ground water flow (Figure 14). Overburden to bedrock vertical

gradients are upward to the northeast of RRDD#1 property ranging from 0.002

ft/ft to 0.082 ft/ft (Table 13). As shown in Figure 27, flow paths from the


overburden and shallow to deep bedrock zones are upward toward the

Farmington River Floodplain indicating that the floodplain is a local ground

water discharge area. Based on the data, contaminated ground water movement

from the Barkhamsted Site will eventually flow to the floodplain.

4.04 Ground Water Sampling

Ground water samples were collected from December 28, 1992 through January

6, 1993 from all site monitoring wells to characterize and quantify the contaminants

within the various water bearing zones.

4.04.1 Methods

Ground water samples were collected in accordance with the procedures

specified in the FSP (Appendix FSP-J). Prior to ground water sampling, a

complete round of static ground water elevations was collected from the site

monitoring wells. Based upon historical ground water quality data, monitoring

wells were sampled in an order from suspected least contaminated to most

contaminated. Ground water sampling equipment was decontaminated in

accordance with procedures included in the FSP (Appendix FSP-D). In addition.

subsequent to well purging, purge water was handled in accordance with

procedures included in FSP Appendix FSP-A. Ground water field sampling logs

are contained in Appendix F.

Each ground water sample was shipped to Pace Laboratories, Inc. in

Wappingers Falls, New York using approved chain of custody procedures.

Samples were analyzed for the TCL/TAL parameters listed in Table 5.

Analytical results for volatiles, semivolatiles, pesticides/PCBs and metals are


summarized in Tables 14A through 14Ds, respectively. A discussion of

monitoring well sample results is presented below.

4.04.2 Results

Background Ground Water Quality Conditions

Monitoring well nests MW-112, MW-113, MW-114, MW-115, and MW

116 are located to the south, west, and east of the landfill disposal area as shown

in Figure 18. These well nests were located to assess the ground water quality

upgradient and adjacent to the landfill disposal area relative to ground water

flow across the site. Results of the TAL/TCL analysis from this area is discussed

below:

• Results of the TCL volatile analysis are discussed as follows:

VOCs were not detected in the MW-112, MW-114, MW-115, or

MW-116 well nests. In addition, VOCs were not detected in

MW-113S.

Monitoring wells MW-113B, MW-1131, and MW-113D detected

toluene at 2 jzg/L , 3 /xg/L, and 16 fig/L. respectively.

• Semivolatile results are discussed as follows:

Bis(2-Ethylhexyl)phthalate was detected in the MW-112 nest, and

in MW-113S, B, & I, the MW-114 nest, MW-115B, and the

MW-116 nest at estimated concentrations below the quantitation

limit.


Di-n-butylphthalate was detected in the MW-112 nest, MW-113S,

and MW-114S at estimated concentrations below the quantitation

limit.

The compound 4-nitroaniline was detected in MW-1131 at an

estimated concentration below the quantitation limit.

The compound N-nitrosodipheylamine and 3-nitroaniline were

detected in MW-115B at estimated concentrations below the

quantitation limit.

• PCB/pesticides were not detected upgradient or adjacent of the landfill

disposal area.

• A discussion of the background metal concentrations is as follows:

Monitoring well MW-113S detected beryllium (2.8 /ig/L),

chromium (143 ng/L), and antimony (25.4 /zg/L) at concentrations

above the federal MCLs for drinking water.

Monitoring well MW-114S detected antimony (32.3 /zg/L).

beryllium (3.1 ng/L), chromium (197 /ig/L), and nickel (155

/xg/L) at concentrations exceeding the federal MCLs for drinking

water.

Monitoring well MW-116S detected antimony (33.9 îg/L),

beryllium (4.2 /ng/L), chromium (266 /ng/L), and nickel (137

/ig/L) at concentrations above the federal MCLs for drinking

water.

Beryllium concentrations were greater than the federal MCL in

MW-115S (2.6 /xg/L) and MW-116B (1.5 /xg/L)


The chromium concentration in MW-115S was 106 /xg/L, which

exceeds the federal MCL.

The results of TCL analysis upgradient and adjacent to the landfill

disposal area indicate that the ground water in areas encompassed by monitoring

well nests MW-112, MW-113, MW-114, MW-115, and MW-116 has not been

impacted by the landfill disposal area. Based on these results, the analytical

data from these wells will be used to represent background ground water quality

at the Barkhamsted Site.

The TAL metal analytical data from the wells have been utilized to

assess ground water quality downgradient (north) of the landfill disposal area.

Downgradient overburden concentrations are evaluated in relation to MW-112S

and MW-113S, and shallow bedrock concentrations are evaluated in relation to

MW-112B and MW-113B. The intermediate and deep bedrock metal

concentrations are evaluated in relation to the background range established in

MW-113I and MW-113D.

The most widespread migration of site-related compounds in ground

water at the Barkhamsted Site is best characterized by the extent of VOCs and

semivolatiles. A comparison of VOC concentrations and semivolatile

concentrations indicates that total concentrations are similar in the vicinity of the

landfill disposal area; however, VOC concentrations exceed semivolatile

concentrations downgradient. Therefore VOC concentrations were utilized to

discuss the extent of the contaminant plume at the Barkhamsted Site.

Figures 28, 29, 30, and 31 depict the VOC plumes in the overburden,

shallow bedrock, intermediate bedrock, and deep bedrock water bearing zones,


respectively. As indicated from the figures and discussed above, the

background well nests contain trace levels of VOCs in the shallow, intermediate

and deep bedrock water bearing zones. Well nests MW-113, MW-114, MW-115

and MW-116 define the contaminant plume at their respective locations on site.

North of the Landfill Disposal Area

The following is a discussion of the ground water quality north of the

landfill disposal area. The area north (downgradient) of the landfill is structured

into discussion of each aquifer zone (overburden; shallow, intermediate and deep

bedrock zones).

Overburden Zone

The overburden VOC contaminant plume is centered in the vicinity of

MW-1S as shown in Figure 28. The overburden plume is oriented in a north

to south direction around well MW-101S to the north and MW-110S to the

south. VOCs were not detected in MW-104S, MW-105S, and MW-113S

(Figure 28). The Unnamed Brook defines the northern extent of the overburden

plume and MW-113S defines the southern extent on the RRDD#1 property. As

discussed above, the western boundary does not extend beyond MW-107S and

MW-114S, and the eastern boundary does not extend beyond MW-115S and

MW-116S.

The overburden VOC plume migrates off the RRDD#1 property to the

northeast. As the plume extends off-site, the Unnamed Brook defines the

northwestern boundary, and MW-102S, MW-103S and MW-1088 define the

southeastern boundary. The downgradient extent of the plume is defined by


MW-111S which is located along the Unnamed Brook on the Farmington River

floodplain.

The overburden contaminant plume contains VOCs, semivolatiles and

metals as discussed below:

• VOCs detected within the overburden plume consist primarily of acetone,

2-butanone, toluene, methylene chloride, and 4-methyl-2-pentanone.

Acetone concentrations within the plume ranged from 38 jig/L in

S-3 to 13,000 Mg/L in MW-1S.

Concentrations of 2-butanone ranged from 30 /xg/L in S-3 to

30,000 pg/L in MW-1S.

Toluene concentrations ranged from 200 /ig/L MW-5S to 7600

/xg/L in MW-11 OS.

Methylene chloride concentrations ranged from 320 /xg/L in MW

1S to 970 ng/L in MW-101S

Concentrations of 4-methyl-2-pentanone ranged from 16 /zg/L in

S-3 to 1400 ng/L in MW-1S.

Other VOCs were detected in the overburden contaminant plume and

included benzene, chloroethane, ethylbenzene, 1,2-dichloroethene, trichloro

ethene, 1,1-dichloroethane, 1,2-dichloroethane, and 2-hexanone.

• The semivolatile compounds which were detected in the overburden

monitoring wells within the plume are discussed as follows:

Concentrations of bis(2-ethylhexyl)phthalate ranged from 0.5/xg/L

in MW-110S to 10,000 /ig/L in MW-101S.


Concentrations of 2, 4-dimethylphenol ranged from 3 /xg/L in

MW-110S to 3100 fig/L in MW-101S.

Concentrations of 4-methylphenol ranged from 62 /xg/L in MW

110S to 45,000 /xg/L in MW-1S.

Concentrations of 2-methylpheriol ranged from 6 jig/L in S-3 to

2600 /zg/L in MW-101S.

Concentrations of phenol ranged from 14 /xg/L in MW-4S to 5600

/ig/L in MW-101S

Semivolatiles were detected in downgradient wells MW-104S and MW

105S. However, concentrations were below the quantitation limits.

Semivolatiles were not detected in the overburden monitoring wells east of

Route 44.

• PCBs/pesticides were not detected in the overburden monitoring wells

above the quantitation limit.

• Overburden metal concentrations were evaluated in relation to the

background range established in wells MW-112S and MW-113S. The

following is a discussion of overburden metal concentrations:

The highest metal concentrations on the RRDD#1 property were

detected within the axis of the overburden plume as defined by

wells MW-101S, MW-1S, and MW-110S (Figure 28). Within

this plume, the most elevated metal concentrations were observed

in MW-1S and ranged from two times background (zinc) to 106

times background (sodium). Overburden ground water metal

constituents which exceeded the federal drinking water MCLs in


MW-1S included barium at 4830 /xg/L, nickel at 139 /xg/L, and

antimony at 120 /xg/L.

The metal component of the overburden contaminant plume

extends to MW-4S and MW-5S where the most elevated metal

concentration (sodium) is 11 times background in both wells.

Antimony concentrations in MW-4S (14.8 /zg/L) and MW-5S

(30.8 /xg/L) were greater than the federal MCL. In addition,

nickel at 112 /xg/L was greater than the MCL in MW-4S.

Although elevated metal concentrations are observed

downgradient of the RRDD#1 property, in general these

concentrations are approximately two times the background

values. Exceptions to this include metal concentrations in MW

105S where sodium is 81 times the background concentration,

and MW-111S where elevated metals range from less than two

times background (thallium) to 17 times background (sodium).

Metal concentrations which exceed federal MCLs in MW-111S

includes beryllium at 9.8 /xg/L, antimony at 25.1 /xg/L. chromium

at 443 /xg/L, and nickel at 375 /xg/L.

Mercury was detected in S-3 and MW-11 IS at 2.0 /xg/L and 0.27

/xg/L. The concentrations are at and below the federal drinking

water MCL of 2 /xg/L.

Shallow Bedrock Water Bearing Zone

The shallow bedrock VOC contaminant plume is centered in the vicinity

of MW-110B to the south, MW-101B to the north, and MW-4R to the northwest


as shown in Figure 29. Similar to the overburden plume, the Unnamed Brook

defines the northern extent of the shallow bedrock contaminant plume. MW

113B defines the southern extent of the plume on the RRDD#1 property. The

western plume boundary does not extend as far as MW-107B and MW-114B,

and the eastern boundary does not extend as far as MW-115B and MW-116B.

The shallow bedrock plume extends off the RRDD#1 property to the northeast.

In this direction, the Unnamed Brook defines the northwestern boundary and MW

102B, MW-103B, and MW-108B define the southeastern boundary. The downgradient

extent of the plume extends beyond MW-11 IB, but not as far as MW-118B.

The shallow bedrock water bearing zone contaminant plume consists of

VOCs, semivolatiles, and metals as discussed below:

• Most of the VOCs which constitute the shallow bedrock plume include

acetone, butanone, toluene, and 4-methyl-2-pentanone as discussed

below:

Acetone concentrations within the plume ranged from 26 pg/L in

MW-1R to 2,000 jtg/L in MW-101B.

Concentrations of 2-butanone ranged from 33 /xg/L in MW-1R to

7,000 pg/L in MW-101B.

Toluene concentrations ranged from 9 j*g/L MW-5B to 11,000

/xg/L in MW-11 OB.

Concentrations of 4-methyl-2-pentanone ranged from 16 /xg/L in

MW-5B to 390 /xg/L in MW-101B.


Other VOCs detected in the shallow bedrock contaminant plume included

ethylbenzene, 1,2-dichloroethane, 1.1 -dichloroethane, benzene, xylenes,

trichloroethene and 1,2-dichloroethene.

• The semivolatile compounds which constitute the shallow bedrock

contaminant plume are discussed as follows:

Bis(2-Ethylhexyl)phthalate was detected at concentrations ranging

from 0.6 Mg/L in MW-105B, MW-108B, and MW-111B to 430

Mg/L in MW-101B.

Concentrations of 2,4-dimethylphenol ranged from 16 /xg/L in

MW-5B to 830 Mg/L in MW-101B.

Concentrations of 4-methylphenol ranged from 0.6 ^g/L in MW

108B to 11,000 Mg/L in MW-101B.

Concentrations of 2-methylphenol ranged from 24 /ig/L in MW

1R to 760 ^g/L in MW-101B.

Phenol Concentrations ranged from 16 ^g/L in MW-l 10B to 1700

/ig/L in MW-101B.

SVOCs were detected in downgradient wells MW-103B, MW-105B.

MW-108B, MW-111B, MW-117B, and MW-118B. However, the downgradient

SVOC concentrations are all below the quantitation limits.

• Heptaclor epoxide was detected at an estimated concentration of 0.03

ug/L in MW-103B. PCB/Pesticides were not detected in any other

shallow bedrock monitoring wells.

• Shallow bedrock metal concentrations were evaluated in relation to the

background range established in wells MW-112B and MW-113B. The


following is a discussion of metal concentrations in the shallow bedrock

zone:

The most elevated metal concentrations were detected within the

axis of the shallow bedrock plume as defined by wells MW-101B

and MW-110B (Figure 29). Within this plume, the most elevated

metal concentrations were observed in MW-101B and ranged

from three times background (antimony, arsenic & silver) to 155

times background (iron). The following metal concentrations

exceeded federal MCLs in MW-101B: antimony at 52.5 jig/L,

barium at 2170 îg/L, beryllium at 13.5 jig/L, chromium at 466

/xg/L, and nickel at 449 ng/L.

Similar to the trends observed in the overburden plume, elevated

metal concentrations in the shallow bedrock zone have been

detected downgradient of the RRDD#1 property. These

concentrations are approximately two to five times background

values. Exceptions to this include metal concentrations in MW

108B, where cobalt is six times the background concentration.

and MW-11 IB where sodium is 19 times background.

Mercury was detected in MW-102B and MW-103B at 0.75 /xg/L

and 1.2 figfL, respectively. Both concentrations are below the

federal MCL of 2.0 /*g/L.

Intermediate Bedrock Water Bearing Zone

The intermediate bedrock VOC contaminant plume is centered in the

vicinity of MW-101I as shown in Figure 30. The plume extends from MW-1011


to the northeast beyond MW-11II. MW-1131 exhibited 3 /xg/L of toluene and

defines the southern extent of the intermediate bedrock VOC contaminant plume

on the RRDD#1 property.

The intermediate bedrock water bearing zone contaminant plume consists

of VOCs, semivolatiles and metals as discussed below:

• The primary VOC constituents of the intermediate bedrock plume are

acetone, 2-butanone, toluene, 1,1 -dichloroethane, and 1,2-dichloroethene

as discussed below:

Acetone was detected in MW-1011 at 270 /ig/L.

Concentrations of 2-butanone ranged from 15 /xg/L in MW-4R-2

to 680 jug/L in MW-101I.

Toluene concentrations ranged from 2 jzg/L in MW-1101 to 29

Mg/L in MW-101I.

1,1-dichloroethane. and 1,2-dichloroethene were detected in MW

1111 at 5 ng/L and 180 /ig/L, respectively.

Estimated trace quantities of trichloroethene were detected in

MW-1061 and MW-4R-2.

• The total SVOC concentrations in the intermediate bedrock wells within

the plume ranged from 1.0 Mg/L in MW-1 111 to 258 /zg/L in MW-1011.

The primary SVOCs detected in MW-101I were 2,4- dimethyl-

phenol, 4-methylphenol, 2-methylphenol, diethylphthalate, and

phenol.

• PCB/pesticides were not detected in the intermediate bedrock zone.


• Intermediate bedrock metal concentrations were evaluated in relation to

the background values established between MW-113I and MW-1131).

The following is a discussion of metal concentrations in the intermediate

bedrock zone:

The most elevated metal concentrations detected in the

intermediate bedrock zone were manganese at 58 times

background in MW-101I, and magnesium at 73 times background

in MW-4R-2. Intermediate bedrock zone metal concentrations

did not exceed federal MCLs.

Elevated metal concentrations were detected downgradient in

MW-111I. These elevated concentrations ranged from less than

two times background (zinc) to 38 times background

(manganese). Downgradient intermediate zone metal

concentrations did not exceed federal MCLs.

Deep Bedrock Water Bearing Zone

The deep bedrock VOC contaminant plume is centered in the v i c imt \ of

MW-101D as shown in Figure 31. The plume extends from MW-101D to the

south to MW-113D. The eastern extent is defined by MW-4R-1 in which no

VOCs were detected.

The deep bedrock water bearing zone contaminant plume consists of

VOCs, SVOCs, and metals as discussed below:

• The volatile constituents which constitute the deep bedrock plume

include acetone, 2-butanone, and toluene.

DRAFT . 119 April 29, 1993

Acetone was detected in MW-101D at 35 /ig/L and in MW-113D

at 31 /ig/L.

2-butanone was detected in MW-101D at 84 ^tg/L.

Toluene concentrations ranged from 3 jug/L in MW-101D to 16

/tg/L in MW-113D.

• Semivolatile compounds were detected in MW-101D at 24.9 ppb.

• PCB/pesticides were not detected in the deep bedrock zone.

• Deep bedrock metal concentrations were evaluated in relation to the

background values established in MW-113D. The following is a

discussion of metal concentrations in the deep bedrock zone:

The most elevated metal concentrations were detected in MW-4R

1 and ranged from less than two times background to 256 times

background (manganese). Metal concentrations within the deep

bedrock zone did not exceed federal MCLs.

4.05 Ground Water Users Survey

\ ground water users survey was conducted to identify and locate residential,

commercial, municipal, and industrial ground water users within a 1 -mile radius of the

landfill. The area covered by the groundwater users survey is illustrated on Figure 32.

The objective of the ground water users survey was to assess potential impacts that the

landfill may have had on ground water users within a 1-mile radius of the Barkhamsted

Site. The ultimate goal of the ground water users survey was to develop a sufficient

data base to implement a domestic supply well sampling program, as described in

Section 4.06.


Methods

The primary method used to gather data on the ground water use within a 1-mile

radius of the Barkhamsted Site was a door-to-door survey. A Ground Water User

Survey Form was developed to obtain property owner information, water supply

information at each property (public water supply source vs. private well), and available

information on any private well on the property. This form was hand delivered to each

residence, business or other institution within a 1-mile radius of the Barkhamsted Site.

Included with the survey form was a letter explaining the purpose of the survey and a

stamped, self-addressed envelope for the convenience of the individual from whom

information was requested. A copy of the Ground Water Use Survey Form and the

accompanying letter is included in Appendix G.

Ground Water Use Survey Forms were hand-delivered to a total of 221

residences, businesses, and institutions (churches, etc.) in December 1992. Responses

were received from a total of 106 residences, 3 businesses, and 1 church for a total of

110 responses. The total percentage of survey response was approximately 50 percent.

The information obtained through the survey was supplemented with additional

information obtained through appropriate local and state agencies, including the

Farmington Valley Health District and the State of Connecticut Department of Health.

Computer data bases from the National Ground Water Association and the USGS were

reviewed, however, detailed information related specifically to ground water users

within a 1-mile radius of the Barkhamsted Site was not available. Results of the ground

water users survey, including data from all available sources, were tabulated and are

included in Appendix H.

DRAFT - 121 April 29, 1993

Results

Although specific information was not obtained from every ground water user

within a 1-mile radius of the site, sufficient information was obtained to conduct a

representative evaluation of the ground water use in the area and the potential impact

that the Barkhamsted Site may have had on the local ground water users.

The results of the ground water users survey indicate that, with the exception of

a small area within the Village of New Hartford, the residences, businesses and

institutions within a 1-mile radius of the Barkhamsted Site utilize ground water as the

primary water supply source. The New Hartford Water Company provides a public

water supply source for some residences within the Village of New Hartford that fall

within the southern most portion of the survey area, including parts of Main Street,

Highland Avenue, and Johnnycake Lane, as indicated on Figure 32.

The local ground water users obtain water supplies from multiple zones within

the overburden and bedrock aquifers. Water supply wells range in depth from shallow

hand-dug wells to 505 feet into the bedrock. The majority of the wells are installed

within the bedrock at depths greater than 100 feet. Well yields are typically less than

10 gallons per minute (gpm), with a few wells reporting yields up to 80 gpm.

The results of the ground water users survey were used to develop a domestic

supply .well sampling program as discussed in Section 4.06.

4.06 Domestic Supply Well Sampling

A domestic supply well sampling program was implemented to evaluate the

potential impacts to local homeowners from ground water contamination at the

Barkhamsted Site. The domestic supply wells to be sampled were selected based on


the Barkhamsted historical ground water flow direction in the bedrock aquifer,

proximity to the landfill, and data collected during the Fuss & O'Neill investigation.

4.06.1 Methods. Locations, and Analyses

Water samples were collected from ten domestic supply wells listed on

Table 15. Table 15 indicates the domestic well depths, if known, and the basis

for sampling selection. The domestic supply well locations are illustrated on

Figure 32.

Prior to sampling each of the domestic supply wells, information was

obtained from the owner as to whether a holding tank was part of their supply

system. All but one domestic supply well (the Eddy residence) was verified as

having a holding tank as part of their water supply system. Domestic supply

well samples were collected at the kitchen faucets of all residents except at the

DMR Landscaping/Accurate Welding property, the Eddy property, and the

Baumann property which were collected from outside faucets. Prior to sample

collection at each property, the water was allowed to flow for approximately

one-half hour to drain the holding tank and/or remove stagnant water from the

system. Well evacuation and sampling procedures were followed in accordance

with the protocols outlined in Appendix FSP-K. of the FSP.

Domestic supply well samples were collected on January 25, 1993. The

samples were analyzed for the TCL/TAL parameters specified on Table 5 using

USEPA drinking water analytical methods. QA/QC samples were collected in

accordance with the procedures identified in the QAPP contained in the RI

DRAFT 123 . April 29, 1993

Work Plan. After sampling was completed at each property, pH, conductivity,

and temperature measurements were recorded and are presented below:

Sampling Point Location pH Conductivity (/xS) Temperature (C°)

Case Residence 10.0 80 9

Jones/Murray Residence 9.9 60 10

Yahne Residence 8.0 210 10

DMR Landscaping / Accurate 8.6 120 11 Welding Property

Young Residence 8.4 50 10

Eddy Residence 8.9 110 10

Swain Residence 8.0 110 11

Baumann Residence 8.1 110 9

Almori Residence 8.2 130 10

Scaramuzza Residence 8.0 50 11

Results of domestic supply well TCL volatile analysis are included on Table 16A.

VOCs were not detected in the domestic supply wells.

A review of Table 16B indicates that the diethylphthalate was detected at a

estimated concentration of below the quantitation limit in the DMR

Landscaping/Accurate Welding sample. No other SVOCs were detected in the domestic

supply well samples.

A review of Table 16C indicates that no PCB/Pesticides were detected in the

domestic supply well samples.

A review of Table 16D indicates that a total of 16 metals were detected in the

domestic supply well samples. Iron was detected in the Swain sample at a

concentration of 4.800 ug/'l, which exceeds the secondary MCL of 300 ppb. Lead was

detected in the Swain sample at a concentration of 29.2 ug/1 which exceeds the federal


action level of 15 ug/1. Antimony was detected in the Swain sample at a concentration

of 16.3 ug/1 which exceeds the federal MCL for antimony of 6 ug/1. It should be noted

that during sampling, the Swain residence expressed concern about potential lead

contamination from an abandoned railroad bed which borders their property to the west.

In addition, lead and antimony are common components of household plumbing (lead

based solder and supply lines) and their detection in the domestic supply well samples

is not considered to be site-related. None of the remaining domestic supply well

samples indicate concentrations of metals above the current federal MCLs for drinking

water.


SECTION 5 - AIR QUALITY ASSESSMENT

5.01 Introduction

This section presents the results of the air quality assessment performed at the

Barkhamsted Site during non-invasive and invasive activities on October 23, 1992,

October 27, 1992, November 16, 1992 and November 17, 1992. The air quality

assessment was performed in accordance with the FSP dated September 1992.

5.01.1 Objectives

The objective of the air quality assessment, as defined in the FSP, was

to collect data for use in evaluating whether site-related residues are being

transported from the site via air transport.

5.01.2 Scope Of Work

The scope of the air quality assessment, as defined in the FSP, was to:

• Collect environmental air samples at designated locations for volatile and

semivolatile compound analysis and compare the results to the

Occupational Safety and Health Administration (OSHA) Permissible

Exposure Limits (PELs) and the American Conference of Governmental

Industrial Hygienists (ACGIH) Threshold Limit Values (TLVs);

Measure respirable paniculate concentrations at the site and compare the

results to the OSHA PEL; and


• Measure the wind speed and direction, temperature, and atmospheric

pressure for use in selecting sampling locations, volume calculations, and

general data interpretation.

Consistent with the FSP, these activities were performed prior to and

during invasive RI activities. The results of the air sampling, in conjunction

with the measured meteorological parameters, will be used to evaluate the

potential transport of site-residues via the air pathway.

5.02 Methodologies

5.02.1 Schedule

Air quality sampling was performed on two occasions: during a period

when no invasive site activities were occurring (non-invasive) and during

monitoring well installation (invasive). The non-invasive air quality sampling

was performed on October 23, 1992 and October 27, 1992, while the invasive

air quality sampling was performed on November 16, 1992 and November 17.

1992.

5.02.2 Approach

Environmental air samples were collected during non-invasive activities

over 2 days for approximately 8 hours each day to establish baseline conditions.

In addition, environmental air samples were also collected during invasive

activities over 2 days for approximately 8 hours each day to simulate "worst

case" conditions. The criteria necessary to define "worst case" conditions were

based on the installation of monitoring wells near potential disposal areas, as


identified in the FSP. This condition was satisfied by collecting air samples

during the installation of wells at monitoring well nest MW-101. During the

LFI Well Inventory, MW-101-S had the highest recorded PID reading (6 ppm)

at the top of the casing of any of the inventoried wells.

A total of seven environmental air sampling stations were established at

the site. The locations of the stations are illustrated on Figure 33. These

locations were selected with the assistance the USEPA. A description of and

justification for selecting each sampling station location is presented below:

• AS-01 was established near monitoring well nest MW-101 to provide

data at a potential point source. Sampling during non-invasive activities

provided background data, while sampling during invasive activities

provided data at a potential point source during "worst case" conditions.

• AS-02 was established on the north-west side of the site near Seep 6 to

provide data during non-invasive and invasive activities.

• AS-03 was established in the center of the landfill disposal area to

provide data in relationship to the fill.

• AS-04 was established on the south side of the site to provide upwind or

downwind data, based on wind direction.

• AS-05 was established near Seep 9 to provide data at a potential point

source during non-invasive and invasive activities.

• AS-06 was established on an adjacent residence property located south

east of the site to provide data at a potential receptor location.

• AS-07 was established on an adjacent residence property located north

of the site to provide data at a potential receptor location.


Airborne paniculate monitoring was conducted at AS-01. This location

was selected to provide data regarding the emission of particulates at an invasive

activity. In addition to the air sampling stations, a meteorological station was

established at the site to provide data on the wind direction and speed,

temperature, and pressure. The meteorological data were used to identify

upwind and downwind sampling stations and to correct the air sampling volumes

for standard temperature and pressure (STP). The meteorological station was

located in the center of the landfill disposal area, adjacent to sampling station

AS-03.

5.02.3 Sampling and Analytical Methods

Volatile Compounds

Volatile organic air samples were collected on a carbon molecular sieve

(CMS) sampling device attached to a personal air sampling pump at the seven

sampling stations. The sampling pumps were pre-calibrated to a flowrate of

approximately 0.04 liters per minute (1pm) according to the FSP standard

operating procedure (SOP) for the collection of environmental air samples.

The air samples were collected continuously over a period of

approximately 8 hours at a height equivalent to the human breathing zone. A

field blank and duplicate samples were collected in accordance with the FSP.

The duplicate samples were collected within 12 inches of an existing

environmental air sampling station, at different locations each sampling day.

Following sample collection, the personal air sampling pumps were post-

calibrated as described in the SOP. The pre- and post-calibration data are


presented in Table 17. The average flowrate. average temperature/sampling day

and average barometric pressure/sampling day were inserted into the generalized

gas law to determine the total sampling volume for each sample.

At the end of each sampling day, collected samples were placed in a

laboratory-supplied airtight vessel and shipped via overnight mail to Pace

Laboratories, Golden, Colorado, in a cooler at a temperature of approximately

4°C. The samples and blank were analyzed by gas chromatography/mass

spectrometry (GC/MS), according to the US EPA method TO-2 and the

laboratory SOP developed for this method.

Semivolatile Compounds

Semivolatile organic air samples were collected at each sampling station

on a glass fiber filter followed by a sorbent tube containing 100 milligrams (mg)

of XAD-2 resin, with 50 mg of XAD-2 resin as a backup. The sampling media

were attached to a personal air sampling pump. The sampling pumps were pre

calibrated to a flowrate of between approximately 0.02 to 0.5 1pm according to

the SOP for the collection of environmental air samples.

The collection of a duplicate sample, sampling duration, and post-

calibration methods were the same as for the volatile samples.

The samples for each sampling day were wrapped in aluminum foil and

shipped via overnight mail to Pace Laboratories, Golden, Colorado, in a cooler

at a temperature of approximately 4°C. The samples and blank were analyzed

by GC/MS, following modified USEPA method TO-13 according to the

laboratory SOP developed for this method.


Airborne Respirable Particulate

Airborne respirable participate concentrations were measured at AS-01

using a Monitoring Instrument for the Environment (MIE) Real-Time Aerosol

Monitor (RAM-1) linked to a datalogger. The datalogger collected continuous

measurements from the RAM-1 including average concentrations.

Meteorological Data

On-site meteorological monitoring was conducted during the

environmental air monitoring program for the following parameters:

• Horizontal wind speed and direction

• Ambient temperature

• Atmospheric pressure

These parameters were measured continuously using a MET-1

meteorological station located in the approximate center of the landfill.

The predominant wind direction for the area is from the southwest

(Climates of the States. 1974). According to the FSP SOP, sampling was to be

postponed if the wind direction on the sampling date differed by more than 90°

as compared to the historical data.

5.03 Observations

Observations described in this subsection correspond to the sampling dates and

sampling stations. Sampling stations are shown on Figure 33.


5.03.1 October 23. 1992

The following observations were noted at the site on this date:

• No invasive activities related to the RI were being conducted.

• Material was being brought into the site for disposal during the sampling.

• The average temperature was 50°F and the average barometric pressure

was 1028 millibars according Northeast Regional Climate Center's

weather station located at Bradley International Airport (Bradley). In

addition, the wind was generally out of the south according to field

observations and meteorological data collected at Bradley. The wind

direction did not differ by more than 90° as compared to the historical

data.

The following table presents the orientation of the sampling stations with

respect to the wind direction, and pertinent observations that could influence the

interpretation of the air monitoring results:

Orientation to Landfill Sampling Observations - October 23, 1992

Upwind Downwind Station

AS-01 X Vehicles operating upwind of AS-01.

AS-02 X Also downwind of Seep 6.

AS-03 Located on landfill; vehicles operating upwind of AS-03.

AS-04 X

AS-05 X Downwind of Seep 9.

AS-06 X Residential receptor; vehicles operating upwind on Rte. 44.

AS-07 Residential receptor.

AS-08 Duplicate for AS-03.


5.03.2 October 27. 1992


• No invasive activities related to the RI were being conducted.


• The average temperature was 50°F and the average barometric pressure

was 1011 millibars according to the weather station located at Bradley.

In addition, the wind was generally out of the north-northwest according

to field observations and meteorological data collected at Bradley. The

wind direction differed by more than 90° as compared to the historical

data, as discussed in Section 5.04.


respect to the wind direction and pertinent observations that could influence the


Orientation to Landfill Sampling Observations - October 27. 1992


AS-01 X


AS-03 Trucks and portable generator operating in vicinity of AS-03.

AS-04 X


AS-06 X Residential receptor, operating upwind on Rte. 44.

AS-07 X Residential receptor; asphalt being applied at a downwind business location.

AS-08 Duplicate for AS-03.

DRAFT April 29. 1993

5.03.3 November 16. 1992


• Invasive activities related to the RI were being conducted at well nest

MW-101.


• The average temperature was approximately 32°F, according to the on-

site meteorological station and Bradley, the average barometric pressure

was 1029 millibars according to Bradley, and the wind was generally out

of the southwest at 5 miles per hour according to field observations, the

on-site meteorological station and Bradley. The wind direction did not

differ by more than 90° as compared to the historical data.




Orientation to Landfill Sampling Observations - November 16. 1992


AS-01 X Also downwind of invasive activity: drill rigs operating in vicinity of AS01.

AS-02 Downwind of Seep 6.

AS-03 On landfill; trucks and portable generator operating in vicinity of AS03.

AS-04 X


AS-06 X Residential receptor.


AS-08 X Duplicate of AS-01


5.03.4 November 17. 1992


• Invasive activities related to the RJ were being conducted at well nest

MW-101.


• The average temperature was approximately 32°F, according to the on-

site meteorological station and Bradley, the average barometric pressure

was 1021 millibars according to Bradley, and the wind was generally out

of the southwest at less than 5 mph according to field observations, the

on-site meteorological station and Bradley. The wind direction did not

differ by more than 90° as compared to the historical data.




Orientation to Landfill Sampling Observations -November 17. 1992


AS-01 X Also downwind of invasive activi ty: drill rigs operating in vicinity of AS01.

AS-02 Downwind of Seep 6.

AS-03 On landfill; trucks and portable generator operating in vicinity of AS03.

AS-04




AS-08 X Duplicate of AS-01


5.04 Modifications

The sampling protocols established in the FSP and SOP were adhered to during

the environmental air sampling project. However, there were minor modifications from

the FSP sampling procedures necessitated by on-site field conditions. The following

statements identify the modifications, their rationale, and the corrective actions taken.

RAM-1

Airborne respirable particulate concentrations were measured

continuously by linking the MIE RAM-1 to a datalogger which electronically

compiled the results to provide average particulate concentrations. However, on

October 23, 1992 and November 16, 1992, the datalogger was not properly

operating and the continuous results could not be logged into the datalogger.

The corrective action taken was to use the airborne particulate measurements

collected on October 27, 1992 (non-invasive day) to establish background

conditions, and to use the measurements collected on November 17. 1992

(invasive day) to measure levels during "worst case" conditions. In addition, on

November 17. 1992 the datalogger was improperly programmed with the wrong

date, November 18. 1992. The proper date was noted when the data was being

transcribed.

Weather Station

On-site meteorological monitoring was conducted continuously during the

environmental air monitoring program for the following parameters:

• Horizontal wind speed and direction

• Ambient temperature

• Atmospheric pressure


However, on October 23, 1992, October 27, 1992, and in the morning of

November 16, 1992 the on-site meteorological station was not fully operational,

due to a defective circuit board in the digital processor. The corrective action

taken was to replace the defective board and collect meteorological information

from the closest airport (Bradley International). On-site data were also collected

using hand-held instruments. In-field observations were made throughout the

sampling event to correlate the airport and hand-held data. This information was

used to determine the sampling volumes and wind directions in place of the on-

site meteorological station.

Volatile Sample Blank

A volatile sample field blank was not collected on October 23, 1992.

Since samples and field blanks were collected in a similar manner during the

other sampling days, the field blank results from the other sampling dates were

used to correct the October 23, 1992 volatile data during the data validation

process.

Wind Direction

Sampling was to be postponed if the wind direction on the sampling date

differed by more than 90° as compared to the historical wind direction ( w i n d s

out of the southwest). However, on October 27, 1992, the wind was generally

out of the north north-west, which differs from the historical data by 180°. In

consultation with USEPA, the samples were collected on this date since invasive

activities were scheduled to begin on October 28, 1992. The locations of the

sampling stations on October 27, 1992 provided upwind and downwind site data,


downwind of point source data, and upwind and downwind receptor data, as

specified in the SOP.

5.05 Results

OSHA establishes PELs, while ACGIH establishes TLVs. Both PELs and TLVs

have been established to provide time weighted average concentrations for a normal 8

hour work day and a 40 hour work week, to which nearly all workers may be

repeatedly exposed, day after day, without adverse effects. OSHA PELs and ACGIH

TLVs have been established to provide a reference for industrial exposure settings and

area not intended to be utilized for evaluating community health issues.

Results of the environmental air monitoring are presented in Table 18. These

tables provide OSHA PELs and ACGIH TLVs for the parameters listed, their respective

sample locations, and the parameter concentration based on the volume of air collected.

The paniculate datalogger results are presented in Appendix I. The strip chart

recording of the meteorological data is provided in Appendix J and the meteorological

data collected at Bradley International Airport is provided in Appendix K. The

sampling survey data sheets are provided in Appendix L.

During the course of the sampling, cars and trucks were observed near and

upwind from the various sampling stations. The fuel used by vehicles may contain

benzene, toluene, ethylbenzene and xylene (BTEX) and the internal combustion of the

vehicles produces the components of BTEX. Therefore, the detection of BTEX at

concentrations below OSHA PELs and ACGIH TLVs may be attributed to the fuel used

by the vehicles and internal combustion.


5.06 Discussion

For all sampling events, all detected volatile and semivolatile compounds were

present at concentrations at least 100 times less than OSHA PELs and ACG1H TLVs.

5.06.1 Non-Invasive Site Activities

October 23. 1992

The following compounds were detected above their respective method

detection limits at one or more of the sampling stations, but not in the other

field blanks and not in the method blank:

• Carbon Tetrachloride

• Chlorobenzene

• Ethylbenzene

Carbon tetrachloride was detected at concentrations below the OSHA

PEL and ACGIH TLV at sampling stations AS-02 (downwind landfil l and

downwind seep), AS-01 (downwind landfill), AS-08 (center landfill dup l i ca te ) .

and AS-07 (downwind receptor).

Chlorobenzene was detected at a concentration below the OSHA P f - L and

ACGIH TLV at sampling station AS-02 (downwind landfill and downwind

seep).

Ethylbenzene was detected at sampling stations AS-03 (center landfill.

AS-08 (center landfill duplicate, AS-02 (downwind landfill and downwind seep).

AS-01 (downwind landfill) and AS-07 (downwind receptor). These results may

be attributed to the fuel used by the vehicles and internal combustion.


The following substances were detected in the samples at concentrations

below OSHA PELs and ACGIH TLV, and in the field blanks collected during

the other sampling dates:

• Benzene

• m,p-Xy!ene

• o-Xylene

• Tetrachloroethane


below OSHA PELs and ACGIH TLV, and in the method blank:

• 1,1,1 -Trichloroethane

• 2-Butanone

• Acetone

• Methylene chloride

• Toluene

Bis(2-ethylhexyl)phthalate

• Di-n-butylphthalate

October 27. 1992


detection limits at one or more of the sampling stations and not in the field or

method blanks:


• Ethylbenzene



PEL and ACGIH TLV at all of the sampling stations, except AS-04 (downwind

landfill).

Ethylbenzene was detected, slightly above the method detection limit, at

sampling station AS-06 (downwind receptor) and AS-08 (downwind landfill and

seep) . This result may be attributed to the fuel used by the vehicles and the

internal combustion.


below OSHA PELs and ACGIH TLV, and in the field blanks collected during

the sampling date:

• Benzene

• m,p-Xylene

• o-Xylene

Tetrachloroethane

• 1,1,1-Trichloroethane

• 2-Butanone

• Acetone


• Toluene

• Di-n-butylphthalate.

The fol lowing substances were detected in the samples at concentration

below OSHA PELs and ACGIH TLV and in the method blank:

• 1.1.1-Trtchloroethane

• o-X\Iene


• Acetone



The average participate concentration at AS-01 (upwind landfill) was

below the OSHA PEL and ACGIH TLV.

5.06.2 Invasive Site Activities

November 16. 1992


detection limits at one or more of the sampling stations and not in the field or

method blanks:

• 1,1 -Dichloroethane

• Benzene


• Ethylbenzene

• m,p-Xylene

• o-Xylene

1,1-Dichloroethane was detected slightly above the method detection l imit

at concentrations below the OSHA PEL and ACGIH TLV at AS-08 (invasive

activity duplicate sample).

Benzene, ethylbenzene, and m,p,o-Xylene were detected at the landfill

sampling station AS-03, These results were below the appropriate OSHA PELs

and ACGIH TLVs. These results attributed to the fuel used by the vehicles and

the internal combustion.



PEL and ACGIH TLV at AS-04 (upwind of landfill), AS-03 (center landfill),

AS-02 (upwind of the landfill and downwind seep), AS-08 (invasive activity

duplicate), AS-05 (downwind landfill and seep), and AS-07 (downwind

receptor).


below OSHA PELs and ACGIH TLV and in the field blanks collected during

the sampling date:

• 1,1,1 -Trichloroethane

• Acetone


• Toluene


. The following substances were detected in the samples at concentrations


• Acetone



November 17. 1992


detection limits at one or more of the sampling stations and were not detected

in the method blank:


• Chlorobenzene



PEL and ACGIH TLV at AS-04 (upwind of landfill), AS-03 (center of the

landfill), AS-02 (upwind of the landfill and downwind of a seep), AS-01

(invasive activity), and AS-08 (invasive activity duplicate).

Chlorobenzene was detected at a concentration below the OSHA PEL and

ACGIH TLV at sampling station AS-02 (upwind of the landfill and downwind

seep).


below OSHA PELs and ACGIH TLV and in the field blanks collected during

the sampling date:

• 1,1,1-Trichloroethane

Acetone

• Benzene

• Carbon Disulfide

• Ethylbenzene

• m,p-Xylene


• o-Xylene

• Styrene

• Tetrachloroethene

• Toluene

• Di-n-but>lphthalate

The following substances were detected in the samples at concentration



• 1,1,1-Trichloroethane,



The average particulate concentration at AS-01 (invasive activity) was

below the OSHA PEL and ACGIH TLV.

5.07 Summary

Compounds were collected at the on-site sampling stations, upwind and

downwind off-site sampling stations, and at the receptors sampling stations during non

invasive and invasive activities. The results of the monitoring were below OSHA PELs

and/or ACGIH TLVs by at least two orders of magnitude. OSHA PELs and ACGIH

TLVs have been established to provide industrial exposure limits for health adult

workers over an 8 hour work day and a 40 hour work week. Since the volatile and

semivolatile levels were well below the OSHA PELs and/or ACGIH TLVs. it is

concluded that the site did not impact the quality of air being transported off-site.


SECTION 6 - SURFACE WATER. LEACHATE AND SEDIMENTS

6.01 General

A total of 15 surface water and 16 sediment samples were collected between

October 27 and November 6, 1992, to characterize the surface water and sediment

quality and to identify the current and/or potential adverse impacts the Barkhamsted Site

may have on the on-site surface waters and sediments, as well as the potential for

transport of these media off-site. The surface water and sediment sampling locations

are illustrated on Figure 34.

Nine leachate seeps were sampled between October 29 and December 11. 1992.

Leachate sampling was performed to characterize and quantify the contaminants in the

leachate, and to identify the potential impacts that the leachate may have had on the

surface waters and/or sediments.

Four storm sewer samples were collected to evaluate the impact the landfill mav

be having on storm water generated on site. Two samples were collected from

catchment basins on site and samples were collected from the two outfalls discharging

storm water to the Unnamed Brook. The location of storm sewer samples are bho\vn

in Figure 34.

6.02 Methods

Surface \vater sampling locations were chosen to evaluate the surface water and

sediment qualitv in samples collected at areas upgradient of the landfill (indicative of

background condit ions) , at on-site areas of concern, and at areas downgradient of the

DRAFT [46 April 29. 1993

landfill. Specific rational for each surface water and sediment sampling location is

explained in the FSP, contained within the RI Work Plan.

Surface water samples were collected approximately 6 inches below the uater

surface at the midpoint of each stream. Pond surface water samples were collected at

the bank of each pond. Surface water samples were collected prior to the collection of

associated sediment samples in order to avoid suspension of sediments which may have

become dispersed in the water column Prior to filling sample containers, a

representative portion of surface water was analyzed in the field for pH, temperature,

conductivity, and dissolved oxygen (Table 19). Water samples were col'ected by

immersing unpreserved sample containers just below the water surface. Preserved

sample containers were filled by collecting water in a decanting vessel and then

decanting the sample into the preserved containers. The decanting vessel \vas

decontaminated in accordance with the procedures outlined in FSP Appendix FSP-D

Surface water samples were analyzed for hardness and the TCL/TAL parameters

outlined on Table 5.

Sediment samples were collected in the same vicinity of each surface uatcr

sample immediately after collection of surface water samples. A stainless steel spoon

was utilized for the collection of each sediment sample. Sediment samples \\ere

collected approximately 6 inches below the sediment surface and placed in a stainless

steel bowl. Excess water was decanted from the sample. Sample containers were then

filled with the sediment in the stainless steel bowl using a stainless steel spoon.

Sediment sampling equipment was decontaminated in accordance with the procedures

outlined in FSP Appendix FSP-D. Sediment samples were analyzed for the TCL/TAL


parameters outlined on Table 5 and for total organic carbon. In addition, sediment

samples were analyzed for grain size using ASTM Method D422.

A total of twelve leachate seeps were mapped and the approximate volume of

flow at each seep was estimated as described in Section 2.05. During the leachate

mapping task, a sample from each seep was collected in a glass jar, covered with

aluminum foil, agitated for approximately 30 seconds and screened with a flame

ionizing detector (FID). Results of FID screening are included in Table 19. Final

leachate sample collection locations were based on field screening, volume of leachate

flow, and potential impacts on surface water bodies along with concurrence from the

USEPA.

Leachate samples were collected at the locations illustrated on Figure 34. Where

leachate seeps did not have sufficient flow for immediate sampling, a hole was dug with

a decontaminated spade, into which was placed a stainless steel bowl flush to the

ground surface. Enough leachate was allowed to collect in the bowl to provide for

sample collection. Prior to leachate sample collection, a representative portion of each

leachate seep was field tested for pH. temperature, conductivity, and dissolved o\> gen

(Table 19). Sample containers were filled by decanting the leachate liquid from the

stainless steel bowl. Leachate samples were analyzed for TOC, BOD, and hardness.

along with the TCL/TAL parameters outlined on Table 5.

Leachate sediments were collected from four leachate seep locations as shown

in Figure 34. Leachate sediments were collected in a stainless steel bowl using a

stainless steel spoon. Leachate sediments were then placed into the appropriate sample

containers. Leachate sampling equipment was decontaminated in accordance with the

procedures outlined in FSP Appendix FSP-D. Leachate sediments were analyzed for


the TCL/TAL parameters outlined on Table 5 and for total organic carbon. In addition.

sediment samples were analyzed for grain size using ASTM Method D422.

Field Modifications

Surface water was not present at SW/SED-1 and therefore only a sediment

sample was collected.

6.03 Surface Water Results

The following is a discussion of the surface water analytical results upgradient,

in the vicinity of the landfill disposal area, and downgradient of the landfill disposal

area.

Upgradient Surface Water Samples

Surface water samples SW-3 and SW-4 were collected in the Unnamed Brook,

upgradient of the landfill disposal area (Figure 34). Results of the TCL/TAL analyses

for volatiles, semivolatiles, pesticides/PCBs and metals are presented on Tables 20A

through 20D, repsectively, and are as follows:

• VOCs were not detected in the upgradient surface water samples.

• SVOCs were not detected in the upgradient surface water samples.

• PCB/pesticides were not detected in the upgradient surface water samples.

• The metal constituents detected in SW-3 and SW-4 included:

Upgradient metal concentrations are similar in SW/SED-3 and SW SED

4. providing a range in which to compare downgradient samples.

Metal concentrations do not exceed federal ambient water level criteria

(AWLQ) for water and fish ingestion with the exception of iron in SW-3

which is approximately four times greater than the AWLQ (Table 20D)


Proximal to Landfill Disposal Area

Surface water samples SW-2, SW-5, SW-6, SW-14, SW-15, and SW-16 were

collected in the vicinity of the landfill disposal area as shown in Figure 34. Results of

the TCL/TAL analyses are as follows:

• VOCs were not detected in the vicinity of the landfill disposal area.

• The semivolatile compounds diethylphthalate and 2,4-dimethylphenol were

detected in SW-15 and di-n-butylpthalate was detected in SW-6 at estimated

concentrations below the quantitation limit. The compound 4-methylphenol was

detected in SW-15 at 16 /zg/L.

• The pesticide 4,4-DDT was detected in SW-15 at an estimated concentration


• Elevated metal concentrations were detected in the vicinity of the landfill

disposal area. Results are as follows:

The bulk of elevated metal concentrations were detected in SW-15 and

ranged from less than two times background (lead and zinc) to 134 times

background (manganese).

Manganese concentrations were greater than both background and the

AQWL in SW-2, SW-5, SW-14, SW-15. and SW-16.

Iron was greater than background and the AQWL in SW-15 and SW-16.

Downgradient of the Landfill Disposal Area

Surface water samples SW-7, SW-8, SW-9, SW-10, SW-ll; SW-12, and SW-13

were collected downgradient of the landfill disposal area off the RRDD#1 property as

shown in Figure 34. Results of TCL/TAL analyses for these samples are as follows:

• TCL volatile results include:


Estimated concentrations of acetone and butanone were detected below

the quantitation limit in SW-8.

Acetone was detected in SW-7 and SW-9 at 11.0 /xg/L and below the

quantitation limit, respectively.

Methylene chloride was detected in SW-10 at an estimated concentration


An estimated concentration of toluene was detected below the

quantitation limit in SW-9.

• All SVOCs detected in the downgradient surface water samples were below the

quantitation limit.

• PCB/pesticides were not detected in the downgradient surface water samples.

• TAL metal results are discussed as follows:

Elevated metal concentrations were detected in all downgradient surface

water samples.

Manganese was the most elevated metal in all downgradient samples

ranging from 23 times higher than background in SW-11 to 60 times

background in SW-9. All manganese concentrations in the downeradient

surface water samples exceeded the AQWL.

• Iron concentrations exceeded the AQWL in all downgradient surface

water samples. Elevated iron concentrations in downgradient samples

were no more than two times background.

• Mercury was detected in SW-13 at 1 /ig/L which is greater than the

AQWL.


Discussion of Surface Water Quality Results

Results of surface water analysis indicated that the surface water in the vicinity

of and downgradient of RRDD#1 is impacted by the landfill. Elevated metal

concentrations are the most significant impact that the landfill has on the surface water.

The highest metal concentrations have been detected in the vicinity of leachate seep

discharges to the Unnamed Brook (SW-13, SW-15, and SW-16).

6.04 Leachate Seep Results

The results of leachate seep TCL/TAL analysis are included in Tables 21A to

21D and discussed below:

• A total of 12 VOCs were detected in the leachate seeps.

Acetone was detected in Seep 1 and Seep 11 at 300 /ig/L.

Benzene was detected in Seep 4, Seep 5, and Seep 7, and Seep 12 at

concentrations below the quantitation limit. Benzene was detected at 1 2

Hg/L in Seep 11.

Chlorobenzene was detected in Seep 4 and Seep 7 at concentrations

below the quantitation limit and 77 ^tg'L. respectively.

Chloromethane was detected below the quantitation limit in Seep 5.

2-Butanone was detected in Seep 1 and Seep 11 at 370 ^g/L and 680

jig/L, respectively.

Ethylbenzene was detected in Seep 7 and Seep 11 at 12 /zg/L, 120 /ig. L.

and 14 jig L. respectively.

4-Methyl-2-pentanone was detected in Seep 1 and Seep 11 at 45 /xg/L.

and 120 /zg/L. respectively.


Toluene was detected in Seep 1 and Seep 11 at 100 /ig/L and 4700 jug/L,

respectively.

Xylenes were detected in Seep 7 and Seep 11 at 31 jug/L and 34 /xg/L,

respectively.

Chloroethane was detected in Seep 11 at 25 /ig/L.

Methylene chloride was detected at an estimated concentration below the

quantitation limit in Seep 12.

Chloroform was detected at an estimated concentration below the

quantitation limit in Seep 11.

• Seep SVOC analytical results were rejected as discussed in the Validation

Report.

• PCB/pesticides were not detected in the seep samples with the exception of Seep

7 which detected dieldrin at an estimated concentration below the detection

limit.

• Seep TAL metal analytical results are discussed below:

Seep 12 contains the highest metal concentrations. This may be due to

the distance the ground water travels from the landfill prior to

discharging in Town of Barkhamsted gravel excavation.

Arsenic was detected in Seep 3, Seep 7, and Seep 11 below the

quantitation limit.

Copper was detected in Seep 11 and Seep 12 28.6 /xg/L and 183 ^g/L.

respectively. Copper was below the quantitation limit in all other seep

samples.


Chromium was detected in Seep 7 at 15.1 /zg/L. All other concentrations

were below the quantitation limit.

Lead was detected in Seep 4 through Seep 12 at estimated concentrations

greater the quantitation limit. Concentrations ranged from 4.5 ^g/L

(Seep 7) to 111 ^g/L (Seep 12).

Mercury was detected in Seep 12 at 0.39 jig/L.

Cyanide was detected in Seep 1, Seep 7 and Seep 10 at estimated

concentrations of 6.3 jig/L, 16.6 /xg/L, and 40.3 pg/L, respectively.

Seep VOC and elevated metal concentrations are consistent with those detected

in other site sample matrices (i.e. soils, ground water). The leachate seeps are directly

impacting the Unnamed Brook water quality.

6.05 Surface Water Sediment Results

The following is a discussion of the surface water sediment analytical results

upgradient, in the vicinity of the landfill disposal area, and downgradient of the landfill

disposal area. Results of the TCL/TAL analyses for volatiles. semivolat i les.

pesticides/PCBs and metals are presented on Tables 22A through 22D. respectively

Upgradient of Landfill Disposal Area

Surface water sediment samples SED-3 and SED-4 were collected in the

Unnamed Brook, upgradient of the landfill disposal area (Figure 34). Results of the

TCL/TAL analyses are as follows:

• VOCs were not detected in the upgradient surface water sediment samples.

• Four SVOCs were detected in the upgradient surface water sediment samples.

All were at estimated concentrations below the quantitation limits.

DRAFT . 154 April 29. 1993

• PCB/pesticides were not detected in the upgradient surface water sediment

samples.

• Upgradient metal concentrations were similar in SED-3 and SED-4 and provide

a range in which to compare downgradient samples.

Proximal to Landfill Disposal Area

Surface water sediment samples SED-1, SED-2, SED-5, SED-6, SED-14,

SED-15, and SED-16 were collected in the vicinity of the landfill disposal area as

shown in Figure 34. Results of the TCL/TAL analyses are as follows:

• TCL volatile analyses detected acetone in SED-6 and SED-15 at 13 MS/kg ^d

41 (j.gfkg, respectively.

• Twenty-one SVOCs were in surface water sediment samples proximal to the

landfill. Most constituents were detected below the quantitation limit with the

exception of the following:

SED-2 detected benzo(b)fluoranthene, fluoranthene, and pyrene at 610

/ig/kg, 460 /zg/kg> and 610 ng/kg, respectively.

• PCB/pesticides results are discussed as follows:

4,4-DDT and methoxychlor was detected in SED-1 below the

quantitation limit.

4,4-DDT was detected in SED-2 at 3.7 jig/kg-

Gamma chlordane was detected in SED-2 and SED-6 at 6.6 ^g/kg and

3.9 Mg^g- respectively.

PCB Aroclor-1254 was detected in SED-2 and SED-6 at 110 /ig/kg and

190 /ig/kg, respectively.


4,4-DDE was detected in SED-2 and SED-6 at 5.8 Mg.'kg and 9.6 /xg/kg,

respectively.

Endosulfan II was detected in SED-2 and SED-6 at 4.0 /zg/kg and 8.9

/xg/kg, respectively.

4,4-DDD, endrin, endrin ketone, and methoxychlor were detected in

SED-2 below the quantitation limit.

Endrin was detected in SED-6 at 3.8 ng/kg.

4,4-DDT, endrin ketone, and methoxychlor were detected in SED-6


• Elevated metal concentrations were detected in the vicinity of the landfill

disposal area. Results are as follows:

Silver, chromium, and sodium were detected in SED-5 at concentrations

less than two times background.

Copper and potassium were detected in SED-2 at concentrations less than

two times background.

Potassium and thallium were detected in SED-14. The potassium

concentration was less than two times background and thal l ium \\as less

than the quantitation limit.

Downgradient of the Landfill Disposal Area

Surface water sediment samples SED-7, SED-8, SED-9, SED-10, SED-11. SED

12, and SED-13 were collected downgradient of the landfill disposal area off the

RRDD#1 property as shown in Figure 34.

• TCL volatile results are discussed as follows:

• SVOC results are discussed as follows:


Thirteen SVOCs were detected in SED-9 ranging from less than the

quantitation limit to 340 //g/kg (pyrene).

Fifteen SVOCs were detected in SED-11 ranging from less than the

quantitation limit to 2300 /ig/kg (pyrene).

Fifteen SVOCs were detected in SED-12 ranging from less than the

quantitation limit to 950 /ig/kg (di-n-burylphthalate).

Acetone was detected in SED-6, -12, -13 and -15 at concentrations

ranging from 13 /xg/kg m SED-6 to 190 /xg/kg m SED-16.

Butanone was detected in SED-12 at a concentration of 52 Mg^g

SED-10 and SED-13 exhibited SVOCs below the quantitation limit.

• PCB/pesticides results are discussed as follows:

Gamma chlordane was detected in SED-9 at 1.8 Mg/kg-

The following constituents were detected in SED-11: PCB Arochlor-1254

at 80 /zg/kg; gamma chlordane at 6.3 /ug/kg; 4.4-DDD at 4.3 p.ejkg; 4.4

DDE at 6.2 jxg^g; an^ 4,4-DDT and methoxyclor at less than the

quantitation limit.

Gamma chlordane was detected in SED-12 at 3.8 jig/kg; 4.4-DDD at 4 b

/xg/L; 4.4-DDE at 4.8 /^g/kg; and methoxyclor at less than the

quantitation limit.

• TAL metal results are discussed as follows:

All downgradient sediment elevated metal concentrations were less than

two times the background values.

Mercury was detected in SED-11 at 0.26 /xg/kg.


As indicated from the sediment analyses surface water sediments have been

impacted by the landfill activities. Landfill precipitation runoff and leachate seeps are

continuing to impact surface water sediments.

6.06 Leachate Seep Sediment Results

The results of leachate seep sediment TCL/TAL analyses for volatiles,

semivolatiles, pesticides/PCBs and metals are included in Tables 22A to 22D,

respectively, and discussed below:

The VOC acetone was detected in Seep/SED-5 and Seep/SED-6 at

concentrations of 150 Mg/kg, 250 jig/kg> respectively.

• SVOCs were detected in all leachate sediments and are discussed as follows:

Six SVOCs were detected in Seep/SED-4 at concentrations less than the

quantitation limits.

Ten SVOCs were detected in Seep/SED-5 at concentrations less than the

quantitation limit.

The following SVOCs were detected in Seep/SED-6: benzol b)

fluoranthene at 770 jig/kg; fluoranthene at 540 ^g/kg; and pyrene at 490

jig/kg. The remaining twelve SVOCs were detected at concentrations

less than the quantitation limit.

The following SVOCs were detected in Seep/SED-11: benzo(a)

anthracene at 340 /xg/kg; benzo(b)fluoranthene at 620 /zg/kg; fluoranthene

at 840 Mg^g; phenanthrene at 420 /xg/kg; and pyrene at 600 /xg/kg. The

remaining fourteen SVOCs were detected at concentrations less than the

detection limit.


PCB/Pesticides results are discussed as follows:

4,4-DDE was detected in Seep/SED-4 at 3.4

Gamma chlordane, PCB Aroclor -1254 and 4,4-DDE were detected in

Seep/SED-5 at 4.4 ng/kg, 42 Mg/kg and 3.7 Mi/kg, respectively. Aldrin

and alpha-chlordane were detected at concentrations less than the

quantitation limit.

The following constituents were detected in Seep/SED-6: 4,4-DDD at 14

Mg/kg, 4,4-DDE at 10 Mg/kg, 4,4-DDT at 15 jug/kg, and alpha chlordane

at 4.7 /xg/kg. Dieldrin was detected at a concentration less than the

quantitation limit.

• Metal concentrations are consistent between the leachate seep sediments.

Leachate seep sediments exhibit contaminants consistent with those observed in

the leachate seeps.

6.07 Storm Sewer Sampling Results

Catchment basins #6 and #15 (CB-6 and CB-15) and storm sewer outfall 31 and

#2 (OS-1 and OS-2) were sampled for the TCLTAL parameters listed in Table 5. The

locations of these samples are shown in Figure 34. The results of analyses for volatiles.

semivolatiles, pesticides/PCBs and metals are presented on Tables 23A through 23D,

respectively, and discussed below:

• The volatile compounds detected included acetone, toluene and methylene

chloride. Acetone was detected in CB-15 at 53 Mg/kg- Toluene was detected

in OS-2, and methylene chloride was detected in CB-6 and CB-15 below the

quantilation limit.


• The semi volatile compound butylbenzylphthalate was detected at estimated

concentrations below the quantitation limit in OS-2.

• PCB/pesticides were not detected in the storm sewer system.

• The highest metal concentrations were detected in CB-15. The metals detected

included cyanide and cadmium which were below the quantitation limits.

Mercury was detected at 0.46 jig/kg.

Catchment basin #15 is the most impacted storm sewer component sampled during the

Phase 1A RI. The basin was sampled because ground water was observed seeping into

the basin through the side walls. CB-15 is located in close proximity to the landfill

disposal area and appears to be draining ground water impacted by the landfill disposal

area.


SECTION 7 - QUALITATIVE ECOLOGICAL ASSESSMENT

7.01 Introduction

This section presents a Phase I qualitative Ecological Assessment (EA) for the

site. The EA was designed in a phased approach to assess whether on-site ecological

receptors could be exposed to site-related compounds before deciding if additional

activities needed to be conducted to evaluate risk or potential off-site impacts.

The EA was performed based on information obtained from regulatory agencies

and two O'Brien & Gere Engineers, Inc. (O'Brien & Gere) site visits conducted on

December 26, 1991, for the Limited Field Investigation (O'Brien & Gere, 1992a) and

October 20-23, 1992 for the EA. The Phase I EA was designed in accordance with

Risk Assessment Guidance for Superjund Volume II Environmental Evaluation Manual

(USEPA, 1989a), and Ecological Assessment of Hazardous Waste Sites: A Field and

Laboratory Reference (USEPA. 1989b). The specific objectives of the Phase I EA are

to:

• Identify potential fish and wildlife receptors in the study area.

• Qualitatively evaluate the potential impacts of exposures to site-related

chemicals on the identified receptors, and

• Evaluate the potential for off-site impacts.

O'Brien & Gere designed this EA, and its associated field elements, to collect

the information necessary to meet the objectives of the Phase I EA. Based on USEPA

Work Plan comments (USEPA, I992a) reflected in the approved Work Plan (O'Brien

& Gere, 1992b), USEPA will perform the identification of compounds of concern, the

determination of exposure point concentrations, and the evaluation of wildlife exposure


pathways typically performed in a Phase I EA. Therefore, consistent with the Work

Plan (O'Brien & Gere 1992b), this Phase I EA focuses exclusively on the identification

of potential wildlife receptors based on information requests and field evaluations of

wildlife inhabitation, and presents this information to USEPA for its evaluation of

impact. However, an independent continuation of this EA may be performed by

O'Brien & Gere for comparative purposes.

The following five tasks were performed to meet the objectives of this Phase I

EA: 1) Covertype Analysis, 2) Wildlife Receptor Evaluation, 3) Wildlife Habitat

Quality Evaluation 4) Qualitative Impact Evaluation, and 5) Potential for Off-site

Impacts. The scope and results of these tasks are presented in the following sections.

7.02 Covertvpe Analysis

The objective of the covertype analysis is to identify the major vegetative

communities and their distribution within 0.5 miles of the site (the study area). The

0.5-mile radius was selected for this site because it incorporates the major covertvpes

in the vicinity of the site from which transient wildlife could visit the site and

potentially be exposed to site-related compounds. The covertype map (Figure 35)

presents the relative sizes and positions of each identified covertype. The covertvpe

map was prepared based on information extracted from existing maps, literature review,

aerial and general photograph review, and a qualitative vegetative census performed

during site visits. Natural terrestrial covertypes were classified according to a

conventional classification scheme for New England forested and nonforested habitats

(DeGraff et al.. 1992)


The following subsections present a general description of the site and

assessment area followed by detailed descriptions of each identified covert\pe.

7.02.1 Site and Study Area Description

As presented in the Work Plan (O'Brien & Gere, 1992b), the site consists

of the RRDD# 1 property and the area between the eastern boundary and Route

44. The site includes active and inactive landfill areas surrounded primarily by

mixed hardwood and conifer forests. Active landfill areas are essentially void

of vegetation. Inactive landfill areas have revegetated with old field/shrub plant

species. The site includes one surface water body, the Unnamed Brook, which

originates south of the site, and flows north along the west side of the landfill

area. The brook flows northeast on-site towards and under Route 44. Various

buildings and roads, associated with active recycling operations at the facility,

are present on the site.

Also as presented in the Work Plan (O'Brien & Gere, 1992b). the studv

area consists of the site and the area traversed by the Unnamed Brook to its

confluence with the Farmington River. Once the Unnamed Brook crosses Route

44, it enters the Farmington River floodplain and runs southeast through a series

of small beaver ponds. South of the ponds, the brook runs along the base of a

steep embankment along the eastern side of Route 44 before entering the

Farmington River approximately 0.25 mi southeast of the site. The floodplain

area is characterized by a mixture of forested upland areas, open fields, and

seasonally saturated wetlands.


Terrestrial, wetland, and aquatic ecological covertypes were identified in

the study area by O'Brien & Gere. Dominant terrestrial covertypes consisted

of white pine-northern hardwood forest, Eastern hemlock forest, old field/shrub,

landfill, and paved/cultural areas. Wetland covertypes consisted of National

Wetland Inventory (NW1) wetlands for off-site areas and delineated wetlands for

on-site areas. On-site wetlands were identified and delineated by O'Brien and

Gere based on current federal guidelines (Environmental Laboratory, 1987). The

aquatic communities in the study area include the Unnamed Brook with

associated beaver ponds, a small pond located northwest of the site, and the

Farmington River. Although the surface water areas are also considered NWI

wetlands, they are discussed as aquatic covertypes in this EA. The physical

characteristics of each covertype are described in the following sections.

7.02.2 Terrestrial Covertvpes

White Pine-Northern Hardwood Forest

The landfill area is surrounded by mixed hardwoods and conifers tvpical

of a white pine-northern hardwood forest covertvpe. Off-site, this coxerupe is

found in upland areas of the Farmington River floodplain. Dominant canopy

species in this covertype consist of Northern red oak (Quercus nigra), red

maple (Acer rubrum). Eastern white pine (Pinus strobus), sugar maple (Acer

saccharum), white oak (Quercus alba), American beech (Fagus grandifolia),

white birch (Betula papyrifera), gray birch (Betula populifolia), and Eastern

hemlock (Ttuga canadensis). Dominant trees in this covertype are


approximately 12 to 16 inches in diameter, indicative of a middle-aged stand.

The majority of the canopy is closed, resulting in a limited shrub layer.

Understory shrubs and saplings consist of mountain laurel (Kalmia latifolia),

Northern red oak, red maple, white oak, Eastern hemlock, and Eastern white

pine. The herbaceous layer varied with the degree of canopy closure supporting

ferns such as Christmas fern (Polystichum acrostichoides) and New York fem

(Thelypteris noveboracensis). A list of vegetation observed in the white pine-

northern hardwood forest is presented in Table 24.

Eastern Hemlock Forest

Southwest of the landfill is a relatively small Eastern hemlock forest,

dominated by Eastern hemlock with lesser numbers of white birch interspersed.

Trees in this covertype are approximately 6 to 14 inches in diameter. In areas

where the canopy is dense, the sapling layer consists primarily of eastern

hemlock and white birch. The herbaceous layer was essentially lacking in this

covertype likely due to the closed canopy and the acidity of the soil caused by

the hemlock. A list of vegetation observed in the Eastern hemlock forest is

presented in Table 25.

Old Field/Shrub

Portions of the inactive landfill and the area between Route 44 and the

Farmington River are communities best described as an old field/shrub

covertype. Portions of the old field/shrub areas near the Farmington River are

seasonally Hooded, Periodically, portions of this area are mowed by

Connecticut Department of Environmental Protection (CTDEP) to maintain early


successional vegetation for its wildlife value (Wilson, 1993). These areas

provide rich floodplain type habitat, dominated by tall grasses and herbaceous

vegetation such as golden rod (Solidago spp.), sedges (Carex spp.), grasses

(Bromus spp.), greenbrier (Smilax spp.), and staghorn sumac (Rhus typhina).

Inactive landfill areas are also representative of this covertype, resulting from

revegetation following landfill disturbances. A list of vegetation observed in the

old field/shrub covertype is presented in Table 26.

Active Landfill

The active landfill covertype is the area that receives fill material and soil

covering. No vegetation was observed in the active portions because of the soil

disturbances.

Cultural/Paved Areas

The cultural/paved area covertype includes man-made structures (i.e.

buildings, roads) constructed for human use. Cultural/paved areas within the

study area consist of Route 44, access roads to the landfill, the recycling

buildings and office, a Department of Transportation salt storage facility, and

residential homes. These areas are not vegetated except for ornamental lawns

included in this covertype.

7.02.3 Wetland Covertvpe

The presence of wetlands within 0.5 miles of the site was evaluated

through a review of NWI maps, the Litchfield County soil survey, and by

delineating wetland boundaries in accordance with current federal methodology.


Dominant tree species observed in the wetland areas include American elm

(Ulmus americana), cottonwood (Populus deltoides), honeylocust (Gleditsia

triacanthos), American sycamore (Platanus occidentalis), American hornbeam

(Carpinus caroliniana), and silver maple (Acer saccharinurri). Common shrub

species include dogwoods (Cornus spp.), and golden rod. No submerged or

emergent vegetation was observed in the main channel, however adjacent

inundated areas contained grasses and herbaceous vegetation tolerant of wet

conditions. A list of vegetation observed in the wetland covertype is presented

in Table 27.

Each of the identified wetland types is discussed below.

NWI Wetlands

The NWI maps present classifications of wetlands using alphabetical and

numerical designations developed by Lewis M. Cowardin (Cowardin, 1979) for

the U.S. Fish and Wildlife Service (USFWS) which describe hydrologic and

vegetative characteristics of the wetland. The NWI maps present \vetland

boundaries on topographic maps based on USFWS wetland criteria established

as an indicator of waterfowl production areas. NWI wetlands are not intended

for federal regulatory purposes. Figure 36 presents the locations of NWI

wetlands within a 0.5-mile radius of the site.

A review of the NWI maps for the area indicates that one USFWS

designated wetland occurs on the site, the Unnamed Brook. The Unnamed

Brook, flowing from southwest to northeast across the site, is classified as

PFO4E - a palustrine, forested, needle-leaved evergreen, seasonally saturated.


North and east of the site, the Unnamed Brook runs through several palustrine

wetland areas classified as: PFO1C - forested, broad-leaved deciduous,

seasonal; PFO/SS1A -forested/scrub/shrub, broad-leaved deciduous, temporary;

PSS1C - scrub/shrub, broad-leaved deciduous, seasonal; PSS1/EME

scrub/shrub/emergent, broad-leaved deciduous, seasonal saturated; PEMA

emergent, temporary; PEMC - emergent, seasonal; and PEMFb - emergent,

semipermanent, beaver.

The Farmington River and Unnamed Brook wetland areas east of Route

44 are the most extensive wetlands in the study area. The Farmington River

floodplain, reaching approximately 1000 feet in width, contains two palustrine

wetlands classified as PF01A - forested, broad-leaved deciduous, temporary; and

PFQ1C - forested, broad-leaved deciduous, seasonal. The Farmington River is

classified as R3OWH - riverine, upper perennial, open water, permanent.

Other palustrine wetlands within 0.5 miles of the site include POWH

open water, permanent - a small pond located northwest of the site; PFO1E

forested, broad-leaved deciduous, seasonal saturated - a small intermittent stream

north of the site; and PFO4E - forested, needle-leaved evergreen, seasonal

saturated - an intermittent stream north of the site.

State of Connecticut Wetlands

Wetlands are defined and regulated by the State of Connecticut based on

soil type (Flores. 1992). The Litchfield County soil survey (USDA, 1970) was

reviewed to identify the soil types on the site. Identified soil types were

compared to the Connecticut List of Map Units that Qualify as Wetland Soils.

Based on this review, Leicester, Ridgebury, and Whitman very stony fine sandy


loam, designated "Lg" on the soil map, is the only wetland soil occurring in the

study area. Figure 37 presents the location of this wetland soil in the study area.

Federal Wetlands

Wetlands are defined and regulated at the federal level by the US Army

Corps of Engineers (ACOE) and USEPA. The currently accepted federal

method for wetland identification and delineation is the 1987 Army Corps of

Engineers Wetland Delineation Manual (Environmental Laboratory, 1987). In

accordance with this manual, wetland criteria require the presence of hydric

soils, a dominance of hydrophytic vegetation, and wetland hydrology.

Consistent with the Work Plan (O'Brien & Gere, 1992b), only on-site wetlands

were identified and delineated. Although it is recognized that the Unnamed

Brook is a wetland, wetlands were only delineated in those areas that met the

criteria outside of the main brook channel. Six wetlands were delineated on the

site by O'Brien & Gere in accordance with the 1987 ACOE method. The

wetland areas include a small isolated pond on the northern portion of the site.

two isolated sedimentation basins located south and west of the landfill , and

three areas along the Unnamed Brook. Along the Unnamed Brook, two

wetlands were located on either side of the old stone bridge, and the third

wetland was associated with the headwaters of the brook, leading towards the

western site boundary. The wetland boundaries are presented'in Figure 38.

Documentation of the wetland boundaries is presented in O'Brien & Gere's

Wetland Delineation Report (O'Brien & Gere, 1993) which is presented in

Appendix A.


Using the Cowardin system of classification, the six identified wetlands

would be classified as follows: the small pond. POWF - palustrme. open water,

permanent; the sedimentation basins, PUBhx - unconsolidated bottom, permanent

excavated; and the areas along the Unnamed Brook, PFO1Y - forested, broad

leaved deciduous, saturated/semi-permanent/seasonal.

Wetland Functions and Values

In accordance with the Work Plan (O'Brien & Gere, 1992b), the

functions and values of non-isolated wetlands, potentially impacted by the

landfill, were evaluated using the Wetland Evaluation Technique (WET)

developed by Paul Adamus for the ACOE (Environmental Laboratory 1987).

WET evaluates the functions and values of wetlands based on their physical,

chemical, and biological characteristics. The WET analysis is presented in

Appendix M.

The delineated wetlands on either side of the old stone bridge were

identified as the Assessment Area (AA) tor the WET analysis as these wetlands

are the only non-isolated wetlands that occur on-site and downgradient of the

landfill. WET was run using current conditions and average flow regime^ The

watershed of the AA was identified as the input zone and the locality for the

evaluation, and the Farmington River was identified as the Service Area. Table

28 summarizes the results of the WET analysis.


7.02.4 Aquatic Covertvpes

The aquatic covertypes include the Unnamed Brook on-site, the Unnamed

Brook off-site, a small pond on the northern portion of the site, and the

Farmington River. A discussion of each of these areas is presented below.

The Unnamed Brook originates southwest of the landfill and flows north

along the western boundary of the landfill. Average width and depth ranged

from approximately 2 to 4 feet and 1 to 8 inches, respectively. The flow rate

varied from 4 to 12 inches/second over a substrate containing mostly rocks and

boulders. The brook consists primarily of riffles with an occasional small (6 to

8 inch) pool. No submerged or emergent vegetation was observed in the main

channel. The portion adjacent to the landfill contained water with an orange

coloration. Water was clear in the more southern portion of the brook. No fish

species were observed. Amphibians and aquatic macroinvertebrates inhabited

the brook. Physical characteristics (DO, pH, specific conductance, temperature)

of the Unnamed Brook on-site are presented in Table 19. On-site Unnamed

Brook surface water sampling locations are designated SW-4. SW-05. SW-06.

SW-07, SW-09, SW-10. SW-13. SW-14. and SW-I5.

The off-site portion of the Unnamed Brook flows into the Farmington

River floodplain where it is temporarily impounded by a series of beaver dams

between forested upland areas. The first and northernmost pond was 4 to 6

inches deep over a muddy substrate. The average depth of the other ponds was

approximately 3 to 4 feet. The brook continues south along the eastern edge of

Route 44 before converging with the Farmington River approximately 0.25 mi

southeast of the site. The width and depth of the brook downstream of the


beaver ponds ranged from approximately 2 to 10 feet and 1 to 8 inches,

respectively. The flow rate was approximately 12 inches/second over a rocky

substrate. Portions of the brook contained submerged grasses. Physical

characteristics (DO, pH, specific conductance, temperature) of the Unnamed

Brook off-site are presented in Table 19. Off-site Unnamed Brook sample

locations are SW-11 and SW-12.

The small (approx. 3500 sq ft) pond, located in the northwest portion of

the site occurs in a forested area. Runoff from steep adjacent terrain collects in

this localized depression which is approximately 2 to 3 feet deep. High flows

of the Unnamed Brook may enter this pond at times. Overflow from the pond

could discharge to the Unnamed Brook. No submerged or emergent vegetation

was observed during field investigations. Physical Characteristics (DO, pH,

specific conductance, temperature) of the pond are presented in Table 19. The

pond sample location is SW-8.

The west branch of the Farmington River is located east of the site. The

average width is approximately 200 feet. Average flow rate, measured in

Unionville, CT. seasonally fluctuates between 1 and 7 feet/second (Cemone.

1993). The river's substrate is rocky and the average water depth ranges from

3 to 6 ft. The western shoreline is relatively flat and rises approximately 5 ft

above the observed water level. The eastern shoreline is relatively steep, rising

approximately 20 to 40 ft above the observed water level. This segment of the

river is being considered for listing as a Wild and Scenic River under the Wild

and Scenic Rners Act of 1968. Figure 39 presents the 100-year and 500-year

floodplain zones for the Farmington River and a small southern portion of the


Unnamed Brook. No surface water samples were collected from the Farmington

River.

7.03 Wildlife Receptor Evaluation

The objective of this task is to identify wildlife species that inhabit the study

area that could potentially be exposed to site-related compounds. Ecological receptors

were identified through contact with state and federal agencies, during transects walked

specifically for this purpose during site visits, and by identifying typical inhabitants of

the identified covertypes through literature review. Resident and transient fish or

wildlife species that frequent the site or adjacent areas were identified based on actual

sightings; observations of wildlife indicators such as nesting places, burrows, tracks,

scat or browse; or audible indicators such as bird songs.

7.03.1 Special Resources

According to U.S. EPA (1989a), potential ecological receptors inc lude

special resources such as environmentally sensitive areas: significant habitats .

rare, threatened or endangered species (RTE): regulated wetlands: streams: lakes.

and Wild and Scenic rivers. The objective of this task is to identify special

resources within the study area. Special resources were identified through

contact with state and federal agencies and review of the NW1 maps.

Rare. Threatened, or Endangered Species

Information'regarding the presence of RTE wildlife species in the vicinity

of the site was provided by CTDEP, Natural Diversity Data Base and the

USFWS. Information from the above agencies was requested for a 2 mile radius

DRAFT . 173 April 29. 1993

from the site to account for the larger home range of some RTE species.

According to CTDEP Natural Diversity Data Base, there are no known extant

populations of Federally Endangered and Threatened Species or species

proposed for State Endangered, Threatened or Special Concern occurring at the

site (Meltzer, 1992). According to the USFWS, no Federally listed or proposed,

threatened and endangered species under the jurisdiction of the USFWS are

known to occur within 2 miles of the project area (Beckett, 1992). However,

the CTDEP Wildlife Division indicated that wintering bald eagles (Haliaeetus

leucocephalus), which have migrated from the north, use the Farmington River

habitat during the winter months for feeding and resting. The bald eagle is

listed as an endangered species in the State of Connecticut as well as federally.

Bald eagles nesting in the Barkhamsted Reservoir area (more than 2 miles away)

may use the Farmington River as a feeding site during the summer months

(Wilson. 1993).

Regulated Wetlands

Wetlands in the study area were previously identified and discussed in

Section 1.02.3 of this EA.

Wild and Scenic Rivers

According to the National Park Service (NPS), two segments of the

Farmington River are currently being studied and considered for listing as Wild

and Scenic Rivers under the Wild and Scenic Rivers Act of 1968 (Huffman,

1993). One segment is located in Massachusetts and the other begins in

Hartland. Connecticut and extends 14 miles downstream to the southern extent

of the New Hartford - Canton town line including the segment east of the site.


Study segments are subject to the same protective status as a listed river,

requiring NFS approval for any water resources project requiring federal

assistance (permit, license, funding etc.) that may adversely impact the study

segment (Huffman, 1993).

7.03.2 Terrestrial Habitat Receptors

Several transects were walked during a 4-day site visit in the fall to

identify terrestrial mammals, amphibians, reptiles, and resident and migratory

birds. Terrestrial wildlife species observed in the study area are summarized in

Table 29. Typical wildlife inhabitants of the terrestrial covertypes, as identified

in the literature, are presented in Table 30.

7.03.3 Palustrine Habitat Receptors

With the exception of bird species, direct animal sightings were limited

during the O'Brien & Gere site visits. Bird species observed in the Farmington

River wetland area include Northern cardinal (Cardinalis cardinally}. Northern

mockingbird (\limus polygloitos). Eastern bluebird ( Stalls stalls), and tut ted

titmouse (Parus bicolor). In addition, a Northern oriole (Icterus galbula) nest

was also sited. White-tailed deer (Odocoileus virginiana) tracks indicated recent

activity in this area. Typical wildlife inhabitants of palustrine habitats, as

identified in the literature, are presented in Table 31.

DRAFT 175 . April 29. 1993

7.03.4 Aquatic Habitat Receptors

The surface water of the Unnamed Brook was surveyed for

macroinvertebrates using USEPA kick net sampling techniques (USEPA, 1989c).

The invertebrate assessment was performed in the Unnamed Brook at three

locations: at the furthest downstream location on-site (Assessment Area #1);

adjacent to the landfill (Assessment Area #2); and upstream (west) of the landfill

(Assessment Area #3). Both rocky and sandy substrates were sampled at each

location except for the location upstream of the landfill, where sandy substrate

could not be found. Macroinvertebrates were counted in a 10 sq ft section of

water at each location. Sufficient quantities of macroinvertebrates were not

present for statistical analysis of potential population effects but do provide an

indication of the benthic community. Table 32 summarizes the observed

macroinvertebrates at each location.

No fish were observed in any surface waters of the site. A brook trout

was observed being caught by a fisherman on the Farmington River during field

investigations. The CTDEP Division of Fisheries indicated that the ent i re

segment of the Farmington River in the study area is located wi th in a 3 5 mi le

trout management area which is stocked with brook trout (Salvelinus Jontmalis)

and rainbow trout (Oncorhynchus mykiss) for recreational fishing (Hyatt, 1993a).

Atlantic salmon (Salmo salar) and long-nose dace (Rhinichthys cataractae) are

reported to be abundant in this portion of the river. (Hyatt. 1993a). Table 33

lists other common fish species of this segment of the Farmington River. The

Unnamed Brook, near the point of confluence with the Farmington River, is

seasonally used primarily by minnow (Family Cyprinidae), darters (Family


Percidae), and trout (Hyatt, 1993b). However, no resident fish species are

known to inhabit the brook (Hyatt, 1993b)

Beaver (Castor canadensis) activity was apparent along the beaver ponds

of the Unnamed Brook, east of Route 44 Freshly gnawed trees and old dams

and lodges were observed, however, no beaver were sited.

7.04 Wildlife Habitat Quality Evaluation

The objective of the habitat quality evaluation is to use the information gathered

during previous tasks to evaluate the ability of study area covertypes to provide the life

sustaining requirements of the identified ecological receptors. High quality habitat

provides sufficient size and resource to support either ecologically or economically

important single species, or a diverse ecological community. Low quality habitat lacks

sufficient size or resource to support important species or diverse communities

The active landfill and cultural/paved covertypes do not provide ûtf ic ient

quantities of vegetation for food or cover and are, therefore, considered to be poor

quality wildlife habitats and are not further discussed in this section

7.04.1 Terrestrial Covertypes

The uhite pine-northern hardwood covertype, containing mixed

hardwoods and conifers, is considered a high quality habitat for a variety of

wildlife species The oak and beech trees of the canopy and understory provide

high quahtv habitat for mast feeding species such as gray squirrel (Sciurus

carolinem>u>>, turkey ( \feleagris gallopavo) and deer, and also provide value as


cover. The food sources and roosting areas provided by birch and hemlock,

respectively, provide a good habitat tor ruffed grouse (Bonasa umbelIns) The

mixed hardwood and conifer forest is preferred habitat for many reptiles, birds

and mammals (DeGraff et al., 1992)

The Eastern hemlock forest covertype also provides abundant cover for

wildlife, but offers fewer food sources than the white pine-northern hardwood

forest. It is preferred habitat for many bird species, small mammals, and for

wintering white-tailed deer (Degraff et al.,1992).

The old field/shrub covertype provides minimal cover or shelter for

wildlife, however many birds and small mammals use these areas for feeding.

The old field/shrub area located in the Farmington.River floodplain is owned by

the Metropolitan District Commission Water Company and is leased by the state

to provide wildlife based recreation to the public (Wilson, 1993). The area is

open to small game hunting during the season and is stocked with pheasants

(Wilson. 1993). This is a high use area for hunting (Wilson. 1993) This

covertype provides food and cover for many bird species and small mammals

(Degraff et al.. 1992).

7.04.2 Palustrine Wetlands

The wetland areas on the site do not provide sufficient water depth and

food sources to attract aquatic furbearers such as beaver, muskrat (Ondatra

:ibethica}. or mink (Mustela vison), or waterfowl such as the wood duck (Aix

sponsa). Vegetation browsers such as the white-tailed deer would find sufficient


food, cover, and water in this covertype to consider this a good qualin habitat.

This covertype is also suitable for a variety of reptiles and amphibians.

Palustrine wetlands in the off-site areas adjacent to the Farmington River

are considered higher quality habitats than the on-site wetlands because of their

proximity and accessibility to the Farmington River. This area would, therefore,

be considered high quality habitat for most of the species discussed above.

7.04.3 Surface Waters

The Farmington River is the highest quality aquatic habitat of the surface

waters in the study area. This major river provides important riparian and

associated wetland habitat for a vast number of wildlife species (Wilson, 1993).

Its physical characteristics, with alternating pools, riffles, runs, and deep water

areas, provide good habitat for trout and salmon species. The presence of trout

and other fish species provide food sources for aquatic furbearers such as mink

and piscivorous birds such as the great blue heron (Ardea herodias).

The beaver ponds of the off-site portions of the Unnamed Brook are of

sufficient size and depth to support the fish. bird, and aquatic furbearcr species

which inhabit the Farmington River and are therefore considered to be high

quality aquatic habitats.

In contrast, the Unnamed Brook on the site is not a high quality aquatic

habitat because it does not support a fish population. The shallow water depths,

low. intermittent flows, absence of submerged and emergent vegetation; and

small macro invertebrate populations provide insufficient habitat requirements to

support economically important fish species. However, it likely provides


drinking water for terrestrial wi ld l i fe and an acceptable environment for a

variety of amphibians and reptiles Depending on the amount of rainfall in the

spring and summer, portions of the Unnamed Brook may be dry during the

summer months

The small pond near the Unnamed Brook is of sufficient depth to support

some non-game fish species; however, its small size and lack of vegetation

provide insufficient habitat requirements to support economically important fish.

This pond could provide habitat for a variety of reptiles and amphibians

7.05 Qualitative Impact Evaluation

The fish and wildlife species that inhabit the different covertypes of the study

area are considered potential ecological receptors for exposures to site-related

compounds. A qualitative evaluation of impact to these receptors requires the

identification of a means of exposure and an evaluation of the result of the exposure

Means of exposure consist of dermal contact, ingestion. or inhalation of site-related

contaminants. The presence of site-related contaminants in surface waters ot the studs

area could result in exposures to aquatic and terrestrial ecological receptors \quat ic

organisms could be exposed to contaminants via uptake from the ambient water or

through the consumption of contaminated sediments, macromvertebrates, vegetation, or

contaminated prey fish Terrestrial wildlife could be exposed via ingestion or dermal

contact with contaminated surface water, soil, vegetation, or lower food chain

organisms. Food chain exposures could result in bioaccumulation of contaminants in

the higher food chain organisms ( i e worms) USEPA has indicated that it will use the

site-related compound concentrations detected in surface water, sediments, and soils to


evaluate exposure point concentrations and model exposures to indicator \\ildlife species

to determine if a potential for unacceptable risk exists for the site (USEPA. 1992b).

The effects of contaminant exposure on aquatic macroinvertebrates can be

evaluated based on observed community structure comparisons between impacted and

control areas. USEPA guidance (USEPA, 1989c) discusses the evaluation of impacts

to macroinvertebrate populations based on the presence and abundance of members of

the Ephemeroptera (mayfly), Plecoptera (stonefly), and Trichoptera (caddisfly) Orders.

Statistical population comparisons were not included in the scope of this assessment,

however the macroinvertebrate community was evaluated from limited data collected

as part of potential stream receptor identification efforts. Macroinvertegrates were

collected from sediments in 10 sq ft areas located upstream, adjacent to, and

downstream of the landfill. The results of this effort are presented in Table 32. As can

be seen from Table 32, organisms from these Orders were only identified in the

upgradient macroinvertegrate assessment area.

The effects of contaminant exposure on particular wildlife species is a funct ion

of the exposure concentrations, the duration of the exposure, and the sensit i \ i t> ot the

exposed species. State (CDEP. 1992) and Federal (USEPA. 1992b) Ambient \Vater

Quality Criteria (AWQC) have been developed by the CDEP and the L'SEPA.

respectively, for the protection of aquatic life. AWQC were used to screen contaminant

concentrations detected in surface waters of the site and vicinity. Exceedance of

AWQC does not necessarily reflect an unacceptable condition. Exceedance of the

reference criteria may trigger the performance of additional Steps of the EA process.

However, because of the safety factor approach used in their derivation, exceedance of

the criteria do not necessarily indicate an unacceptable level of risk to ecological


receptors. Iron, lead, mercury, and zinc concentrations in on-site surface waters slightly

exceed USEPA AWQC for chronic exposures in aquatic environments. Zinc also

exceeds acute USEPA AWQC at one location. Exceedance of the criteria during a

single sampling event is another uncertainty in the evaluation of whether an impact is

occurring or has occurred. The detected concentrations could represent intermittent

contaminant releases, or be indicative of a constant release of low levels.

A comparison of detected compound concentrations in surface water with

Connecticut AWQC was also performed. No volatile or semivolatile exceedances of

criteria were identified. No metal detections were found to exceed criteria but accurate

comparisons for all metals were not possible. The detected total copper, lead and zinc

concentrations in surface water exceed the State AWQC but the criteria apply only to

the soluble fraction of the samples. In accordance with the Work Plan (O'Brien &

Gere, 1992b), the analyzed surface water samples were not filtered prior to analysis.

In addition, the state criterion for mercury only applies to methyl mercury, \vhich was

not analyzed at the site. Therefore, an evaluation of the significance of the detected

concentrations of copper, lead, zinc and mercury could not be performed.

Therefore, an evaluation of impacts can not be performed at this time, based on

a single round of sampling data. An evaluation of potential impacts to ecological

receptors of the site would best be performed based on the results of at least a second

round of surface water and sediment sampling and analysis.

Potential impacts to on-site wetlands downgradient of the landfill were

qualitatively evaluated based on the results of the WET analysis. An impact could

result to a wetland it' the opportunity to provide a function is higher than the

effectiveness of the wetland at performing that function. In the WET analysis, only the


function of nutrient removal/transformation had a LOW effectiveness and a HIGH

opportunity. The HIGH opportunity stems from potential nutrient inputs from the

adjacent landfill area. The LOW effectiveness ranking results from the lack of aquatic

vegetation and fine organic sediments in the main channel to retain, uptake and

transform nutrients. The input of more nutrients than the AA could effectively absorb

would not have a negative impact in a flowing water environment but would allow

nutrients to be transported downstream.

The impact of a toxicant release into the AA can be evaluated based on the

concentration of the release. High concentrations could result in toxicity to vegetation

and aquatic organisms and reduce the quality of the AA. However, currently detected

concentrations of contaminants have not resulted in observable vegetative stress and the

WET analysis has evaluated the AA's ability to retain toxicants to be effectively HIGH.

Therefore, it does not appear that the landfill is impacting the functions and \alues of

the evaluated wetland, but potential wetland inhabitants may be exposed to toxicants

in the wetland.

7.06 Potential For Off-Site Impacts

The objective of this task is to evaluate the potential for off-site impacts to

ecological receptors. Chemical concentrations detected in off-site surface \vater and

sediment samples were evaluated to determine if site-related chemicals have migrated

to off-site areas at concentrations that could impact ecological receptors. As an init ial

screening step, off-site surface water contaminant concentrations were compared to

State and Federal AWQC. Two surface water samples were collected from off-site

portions of the Unnamed Brook in the Farmington River floodplain.


Lead, copper and zinc were the only compounds found to exceed the Federal

chronic AWQC in off-site sampling locations. Zinc was also found to exceed acute

Federal AWQC. No volatile or semivolatile exceedances of State AWQC criteria were

identified. No metal detections were found to exceed State AWQC criteria but accurate

comparisons for all metals were not possible. The detected total lead, copper, and zinc

concentrations in surface water exceed the State AWQC but the criteria apply only to

the soluble fraction of the samples. In accordance with the Work P:lan (O'Brien &

Gere, 1992b), the analyzed surface water samples were not filtered prior to analysis.

Therefore, an evaluation of the significance of the detected concentrations of lead,

copper, and zinc could not be performed.

A background surface water sample, collected upgradient of the site, also

exceeds Federal AWQC for iron, indicating that iron occurs at elevated concentrations

in the vicinity of the site, upgradient to the influence of the landfill. A single sample

is not statistically representative of background, however the iron detection may indicate

either naturally elevated concentrations in the region or an upgradient source of iron

entering the Brook. High iron concentrations in background surface \vater uould

eliminate iron from further consideration at the detected concentrations xvhich onl>

slightly exceed Federal AWQC. Background iron concentrations will be further

evaluated following subsequent surface water quality sampling and analysis.

The presence of contaminants in off-site surface waters indicates that

contaminants may have been released in the past or during different flow and/or

leachate conditions than when the first round of sampling was conducted. However,

no chemical concentrations exceeded Federal AWQC in the surface water sample

located at the furthest downstream location on the site. This information suggests that


contaminants were not being transported off-site at the time of sampling at levels which

give rise to exceedance of the Federal AWQC in surface water. Contaminant

concentrations in the water could change in response to higher or lower flows and

changes in leachate generation. Therefore, an evaluation of off-site impacts should be

deferred until additional rounds of surface water samples can be collected, representing

a variety of leachate and flow conditions.


SECTION 8 - SUMMARY AND CONCLUSIONS

8.01 General

The following provides a summary of the Phase 1A Site Characterization results

with respect to each individual area of investigation. In addition, conclusions are

presented with regard to the adequacy of the Phase 1A Site Characterization for the

purpose of completing a Feasibility Study (FS).

8.02 Summary

50/75 and Sources of Contamination

The geophysical and soil gas surveys were effectively utilized to

delineate the horizontal extent of potential source areas. Results of each

survey served to focus invasive investigations (soil borings).

Resistivity surveys provided correlatable resolution of water table and

bedrock elevations in several locations of the site.

The results of the landfill gas survey indicated that methane gas is

limited to the vicinity of fill areas.

Surface soil sampling results provided validated data for the USEPA risk

assessment. In addition, analytical data correlated with the horizontal

extent of contamination as defined by the soil boring sampling program.

Surface soil sampling of the Yahne property detected low levels of

pesticides. Surface soil sampling of the Jones/Murray property detected

low levels of semi-volatile constituents.


The soil boring installation program provided analytical and physical

characterization of each potential source area. The results revealed that

with the exception of a few discrete soil samples, contaminants were

below the USEPA action levels.

Site Hydrogeologic Characterization

Geologically, the site consists of predominantly ice contact and glacial

outwash/fluvial overburden deposits which overly a pegmatite intruded

micaceous schist metamorphic bedrock.

Hydrogeologically, the site consists of an overburden aquifer which is

hydraulically connected to the bedrock aquifer. The bedrock, which is

moderately to highly fractured, acts as single hydraulic unit.

Ground water flow direction is similar in overburden and the bedrock.

Flow is to the north on RRDD#1 property in the vicinity of the landfill

disposal area. Ground water flow diverts to the northeast, and flows off

the RRDD#1 property, north of the landfill disposal area in the vicinity

of the Unnamed Brook. Ground water from the site discharges in the

Farmington River Flood Plain.

The ground water contaminant plume consists of VOCs, semivolatiles.

and elevated metal concentrations. Contaminant plume VOC and

semivolatile concentrations were similar in the vicinity of the landfill

disposal area; however, VOC concentrations exceed semivolatile

concentrations downgradient. Therefore VOC concentrations were

utilized to assess the maximum extent of the ground water contaminant

plume at the Barkhamsted Site.


The local ground water users obtain water supplies from multiple zones

within the overburden and bedrock aquifers. Water supply wells range

in depth from shallow hand-dug wells to 500 foot bedrock wells.

Air Quality Assessment

The results of air monitoring found that during both non-invasive and

invasive activities , air analyte concentrations were below OSHA PELs

and/or ACGIH TLVs by at least two orders of magnitude.

Surface Water, Leachate, and Sediments

Surface water samples collected upgradient of the landfill disposal area

detected iron above the Federal AWQL criteria for water and fish

ingestion. All other analytes were below method detection limits.

Low levels of VOCs, semivolatiles, pesticides, and elevated metal

concentrations were detected in the surface water samples proximal to

and downgradient of the landfill disposal area.

Twelve leachate seeps were identified at the Barkhamsted Site. Fen ot'

the seeps discharge either directly or indirectly via the storm êuer

system to the Unnamed Brook. One seep originates on the Barkhamsted

Town Garage property, flows overland a short distance and infiltrates

into the ground.

Seep analytical samples detected VOCs and elevated metal

concentrations.

Analysis of stream sediments proximal to and downgradient of the

landfill disposal area detected VOCs, semivolatiles, PCBs/pesticides. and

elevated metal concentrations.


The storm sewer system is impacted by the landfill disposal area. Seep

#11 discharges directly to the storm sewer system. Catchment basin #15

collects ground water which has been impacted by the landfill disposal

area.

Ecological Assessment

The ecological assessment identified terrestrial, wetland and aquatic

covertypes in the vicinity of the Barkhamsted Site. In addition, the

wildlife receptors which reside in and around the covertypes were

identified.

Iron, lead, mercury, and zinc in on-site surface waters exceeded the

USEPA AWQC for chronic exposures in aquatic environments.

Comparison of detected compounds in surface waters to the Connecticut

AWQC found VOCs and semivolatiles did not exceed the criteria.

Based on WET analysis, the landfill is not impacting the functions and

values of on site wetlands. However, potential wetland inhabitants mav

be exposed to toxicants in the wetland.

Lead, copper, and zinc concentrations in off-site surface water s l i g h t K

exceeded Federal chronic AWQC criteria.


8.Q3 Conclusions

The Phase 1A Site Characterization has provided sufficient data to identify and

characterize all potential source areas, evaluate the nature and extent of contaminants,

and assess the environmental effects resulting from releases from the site. The data

generated during the Phase 1A Remedial Investigation will be sufficient for use in

screening and evaluating remedial alternatives. In addition, data has been generated for

the USEPA Risk Assessment.

The following has been concluded from the results of the Phase 1A Site

Characterization:

The results of the soil boring and test pit installations indicate that the

limits of fill encompass potential source Area A, Area B, and the eastern

portion of Area C.

The revised limits of fill increase the landfill disposal area to

approximately 13 acres.

The result of the soils and sources of contamination investigation indica te

that source areas do not exist outside the landfill disposal area.

Therefore, potential disposal Areas A through L, PreviousK Cleared

Areas #1 and #2 and the Recycling Area do not need to be considered

as contaminant sources independently from the landfill disposal area.

The overburden aquifer is hydraulically connected to the Unnamed

Brook.

Higher contaminant concentrations exist in the overburden aquifer and

decrease with increasing depth into the bedrock aquifer.


The contaminant plume from the Barkhamsted Site migrates with ground

water flow. The plume flows north in the vicinity of the landfill disposal

area, then diverts to the northeast, north of the landfill disposal area in

the vicinity of the Unnamed Brook, and flows off the RRDD#1 property

and discharges to the Farmington River Floodplain.

Results of the domestic supply well sampling program indicate that the

domestic supply wells in the vicinity of the site are not impacted by the

site related contaminants.

The surface water in the vicinity and immediately downgradient of the

Barkhamsted Site is being impacted by the landfill in the form of

elevated metal concentrations. The highest elevated metal concentrations

have been detected in the vicinity of leachate seep discharges to the

Unnamed Brook.

Volatile and semi-volatile airborne constituents were below OSHA PELs

and/or ACGIH TLVs indicating the site does not impact the quality of

air being transported off site.


References

QBRIEN G GERE ENGINEERS, INC.

REFERENCES

Beckett, Gordon E. 1992. Personal communication to C.J. Hayes, O'Brien & Gere Engineers, Inc. United States Department of Interior, Fish and Wildlife Service. Concord, New Hampshire. April 21, 1992.

Bouwer, H. and R.C. Rice. 1976. A Slug Test for Determining Hydraulic Conductivity of Unconfined Aquifers with Completely or Partially Penetrating Wells." Water Resources Research. 12(3):423-428.

Bouwer, H. 1989. The Bouwer and Rice Slug Test - An Update. Ground Water. Vol. 27. No. 3.

Cervione, Michael. 1993. Personal communication to Anthony Esposito, O'Brien & Gere, Engineers, Inc. United States Geological Survey, Water Resources Division. Hartford, Connecticut. March 23, 1993.

Chambers, Robert E. 1983. Integrating Timber and Wildlife Management. SUNY College of Environmental Science and Forestry. Syracuse, New York. October, 1983.

Connecticut Department of Environmental Protection (CDEP). 1992. Connecticut Water Quality Standards. Connecticut Department of Environmental Protection, Water Management Bureau. Hartford, Connecticut. January, 1992.

Connecticut Department of Environmental Protection (CDEP). 1987. Water Quality Classification Map of Connecticut.

Cowardin, Lewis M. 1979. Classification of Wetlands and Deep-water Habitats of (he L'nited States. United States Department of the Interior, Fish and Wildlife Service FWS/OBS-79/31. Washington D.C. December, 1979.

DeGraff, Richard M., Mariko Yamasaki, William B. Leak, and John W. Lanier. 1992. AVw England Wildlife: Management of Forested Habitats. United States Department of Agriculture, Forest Service General Technical Report NE-144. Radnor, Pennsylvania. May, 1992.

Environmental Laboratory. 1987. Corps of Engineers Wetlands Delineation Manual. United States Army Corps of Engineers. Washington, D.C. January, 1987.

Flores, Hector. 1992. Personal communication to Molly Khoury, O'Brien & Gere, Engineers, Inc. Connecticut Department of Environmental Resources, Natural Resources Center. Hartford, Connecticut. October 14, 1992.

Fuss & O'Neill. 1990. Scope of Study - Regional Refuse Disposal District #/ Landfill, Barkhamsted, Connecticut.

Fuss & O'Neill. 1991b. RRDDttI Landfill Site Investigation, Regional Refuse Disposal District #7, Barkhamsted Connecticut.

Handman, E.H., Haeni, P.P., and Thomas, M.P., 1986. Water Resources Inventory of Connecticut, Part 9, Farmington River Basin: Connecticut Water Resources Bulletin No. 29, 91 p.

Huffman, Phillip. 1993. Personal communication to Molly Khoury, O'Brien & Gere, Engineers, Inc. National Park Service. Boston, Massachusetts. March 3, 1993.

Hyatt, William. 1993a. Personal communication to Molly Khoury, O'Brien & Gere Engineers, Inc. Connecticut Department of Environmental Protection, Division of Fisheries. Hartford, Connecticut. March 24, 1993.

International Technology Corporation, Wheran Envirotech, O'Brien & Gere Engineers, Inc. 1992. Freshkills Leachate Mitigation System Project Interim Leachate Mitigation Report.

Interpex Limited. 1987. Resix.

Labbe, T.W. and Whitman, R.V. 1965. Soil Mechanics, John Wiley & Sons.

. 1993b. Personal communication to Molly Khoury, O'Brien & Gere Engineers, Inc. Connecticut Department of Environmental Protection, Division of Fisheries. Hartford, Connecticut. March 31, 1993.

Metzler, Kenneth J. 1992. Personal communication to C.J. Hayes, O'Brien & Gere Engineers. Inc. Connecticut Department of Environmental Protection, Natural Diversity Data Base. Hartford, Connecticut. March 5, 1992.

Niering, William A. 1985. Wetlands. Alfred A Knopf, Inc. New York. March, 1985

O'Brien & Gere Engineers, Inc. 1992. Limited Field Investigation Summary Report

O'Brien & Gere Engineers, Inc. (O'Brien & Gere). 1992a. Barkhamsted -New Hartjord Landfill Superfund Site. Limited Field Investigation Summary Report. O'Brien & Gere Engineers, Inc. Syracuse, New York. September, 1992.

. I992b. Barkhamsted - New Hartford Landfill Superfitnd Site. Work Plan. O'Brien & Gere Engineers, Inc. Syracuse, New York. September, 1992.

. 1993. Wetland Delineation Report Draft. O'Brien & Gere, Engineers, Inc. Syracuse, New York. March, 1993.

Schnabel, R.W., 1975. Geologic Map of the New Hartford Quadrangle, Northwestern Connecticut. United States Geological Survey, Geologic Quadrangle Map GQ-1257.

Schnabel, R.W., 1973. Unconsolidated Materials, New Hartford Quadrangle, Connecticut. Map MF-542A.

Sowens, G.F. 1973. "Settlement of Waste Disposal Fills," Proceedings of the Earth International Conference on Soil Mechanics and Foundation Engineering, Moscow.

Todd, David Keith. 1980. Groundwater Hydrology. John Wiley & Sons.

United States Environmental Protection Agency (USEPA). 1989a. Risk Assessment Guidance for Superfund Volume II Environmental Evaluation Manual Interim Final. United States Environmental Protection Agency EPA/540/1-89/001. Washington D.C. March, 1989.

. 1989b. Ecological Assessment of Hazardous Waste Sites: A Field and Laboratory Reference. United States Environmental Protection Agency EPA 600/3-89/013. Washington D.C. March, 1989.

. 1989c. Rapid Bioassessment Protocols for Use in Streams and Rivers. United States Environmental Protection Agency EPA/440/4-89/001. Washington D.C. May, 1989.

. 1992a. Work plan comments. United States Environmental Protection Agency. Boston. April 22, 1992.

. 1992b. Quality Criteria for Water, Updated: December, 1992. United States Environmental Protection Agency, Office of Water Regulations and Standards EPA 440/5-86991. Washington D.C. December, 1992.

United States Department of Agriculture (USDA). 1970. Litchfield County Soil Survey. United States Department of Agriculture, Soil Conservation Service. Hartford, Connecticut.

Winterkorn, H.F., and Fange, H.T. 1975. Foundation Engineering Handbook. Litton Educational Publishing, Inc.

Zhody, A.A.R. 1973. A Computer Program for the Automatic Interpretation of Schlumberger Sounding Curves Over Horizontally Stratified Media. NTIS PB-232-703.

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