Reference 25 Commerce Street Plume

•. Lb EPA ID No. VTD098352545

FINAL SITE INSPECTION PRIORITIZATION REPORT FOR

MITEC WILLISTON, VERMONT

SDMS DocID

CERCLIS No. VTD098352545 TDD No. 98-05-0136

Submitted by:

Roy F. Weston, Inc. (WESTON®) Superfund Technical Assessment and Response Team (START)

217 Middlesex Turnpike Buriington, MA 01803

9 September 1998

Region I START Reviewed and Approved:

o » - g ( . q ^ yi. Andrew Klein, P.E Date Site Leader

^•i?!f^ Jocelyn Boesch Date Project-Leader

fi./! C i/LcA. rSo^mcJ c\.'^-\S ^

QA Review Date

Work Order No. 11098-031-001-5125-70

r V'STAR-nMtTFnviITECFNL WPD 9 Seotember 1998

DISCLAIMER

This report was prepared solely for the use and benefit of the U.S. Environmental Protection Agency Region I (EPA Region I), Office of Site Remediation and Restoration for the specific purposes set forth in the contract between the EPA-Region I and the Roy F. Weston, Inc. (WESTON«), Superfund Technical Assessment and Response Team (START). Professional services performed and reports generated by START have been prepared for EPA Region 1 purposes as described in the START contract. The information, statements, and conclusions contained in the report were prepared in accordance with the statement of work, and contract terms and conditions. The report may be subject to differing interpretations or misinterpretation by third parties who did not participate in the planning, research or consultation processes. Any use of this document or the information contained herein by persons or entities other than the EPA Region I shall be at the sole risk and liability of said person or entity. START, therefore, expressly disclaims any liability to persons other than the EPA Region I who may use or rely upon this report in any way or for any purpose.

C:\START\MITEC\M1TECFNL.WPD H 9 September 199g

TABLE OF CONTENTS

Title Eag£

INTRODUCTION . . . . 1

SITE DESCRIPTION

OPERATIONAL AND REGULATORY HISTORY AND WASTE

1

CHARACTERISTICS 4

WASTE/SOURCE SAMPLING 9

GROUNDWATER PATHWAY 9

SURFACE WATER PATHWAY 14

SOIL EXPOSURE PATHWAY 20

AIR PATHWAY 24

SUMMARY 27

REFERENCES

ATTACHMENT A- MITEC SEDIMENT AND SOIL SAMPLE ANALYTICAL RESULTS START Samples Collected 17 December 1997

C:\START\MITEC\MITECFNL.WPD H I 9 September 1998

LIST OF FIGURES

Figure No. l i t k Page

1 Location Map 2

2 Site Sketch 3

3 Sample Location Sketch 5

LIST OF TABLES

Table No. Title Page

1 Source Evaluation for Mitec 8

2 Hazardous Waste Quantity for Mitec 8

3 CERCLIS and RCRIS Facilities Located within 1-Radial Mile of Mitec 9

4 Estimated Drinking Water Populations Served by Groundwater Sources Within 4-Radial Miles of Mitec 10

5 Maximum Concentrations of VOCs Detected in Groundwater, Mitec and Ailing Industrial Park Properties (1985 to 1988) 13

6 Surface Water Bodies Along the 15-Mile Downstream Pathway from Mitec 15

7 Sensitive Environments Along the 15-Mile Downstream Pathway from Mitec 16

8 Sample Summary: Mitec Sediment Samples Collected by START on 17 December 1997 17

9 Summary of Analytical Results, Sediment Sample Analysis for Mitec 19

10 Sample Summary: Mitec Soil Samples Collected by START on 17 December 1997 21

11 Summary of Analytical Results, Soil Sample Analysis for Mitec 22

C:\START\MITEC\MITECFNL.WPD iV 9 Seplember 1998

LIST OF TABLES (Concluded)

Table No. Title Page

12 Estimated Population Within 4-Radial Miles of Mitec 24

13 Sensitive Environments Located Within 4-Radial Miles of Mitec 25

C;\START\MITEC\MrrECFNL.WPD V 9 September 1998

Final Site Inspection Prioritization Report CERCLIS No. VTD098352545 Mitec TDD No. 98-05-0136 Williston, Vermont Work Order No. 11098-031-001-5125-70

INTRODUCTION

The Roy F. Weston, Inc. (WESTON*) Superfund Technical Assessment and Response Team (START) was requested by the U.S. Environmental Protection Agency Region I (EPA Region I), Office of Site Remediation and Restoration to perform a Site Inspection Prioritization (SIP) of the Mitec property at 15 Commerce Street, in Williston, Vermont. Tasks were conducted in accordance with the SIP scope of work and technical specifications provided by EPA Region I. A Site Inspection (SI) Report for the Mitec property was prepared by the NUS Corporation Field Investigation Team (NUS/FIT) in 1990. Analytical results of sampling activities conducted from 1984 to 1988 at the Mitec property indicated elevated concentrations of volatile organic compounds (VOCs) and inorganic substances in groundwater and surficial soil located on and near the Mitec property. On the basis of the information provided in the SI report, the Mitec SIP was initiated.

Background information used in the generation of this report was obtained through file searches conducted at EPA Region I, the Vermont Agency of Natural Resources (VT ANR), telephone interviews with town officials, conversations with persons knowledgeable of the Mitec property, and conversations with other Federal, State, and local agencies.

This package follows the guidelines developed under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), as amended, commonly referred to as Superfund. However, these documents do not necessarily fulfill the requirements of other EPA Region I regulations such as those under the Resource Conservation and Recovery Act (RCRA) or other Federal, State, or local regulations. SIPs are intended to provide a preliminary screening of sites to facilitate EPA Region I's assignment of site priorities. They are limited efforts and are not intended to supersede more detailed investigations.

SITE DESCRIPTION

The Mitec property is located at 15 Commerce Street in Williston, Chittenden County, Vermont, latitude 44° 27' 09.3' north and longitude 73° 07' 17.0' west, as measured from the center of the property (Figure 1) [1; 2]. The property occupies 1 acre and includes one 6,000 square foot (ff) building (Figure 2). From 1979 to 1986, the Mitec property was used to manufacture electronic and microwave components, involving an electroplating operation, with chemical treatment, acid wash, and a water rinse. From 1972 to 1985, Mitec and previous occupants used an unlined lagoon to dispose of liquid wastes [3; 4, p. 3]. Previous occupants of the property had used the lagoon to dispose of unknown types and quantities of liquid wastes.

C:\STAR'nMITEC\MITECFNL.WPD 1 9 September 1998

BASE kiAP IS A PORTION OF THE F0IX0W1NG 7.5' X 7.5' U.S.C.S. QUADRANGLE: ESSEX JUNCTION. VT 1948, PHOTOREVISED 1972 BURUNGTON, VT 1948, PHOTOREVISED

1 1/2 0

1972

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2000

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: E 4000

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3 F E H

OUADtUMOLC LOCAnOM

LOCATION MAP j j ^ C H Tetra Tech EM Inc. MITEC REGION I SUPERFUND TECHNICAL ASSESSUENT AND RESPONSE TEAM

15 COMMERCE STREET WILLISTON, VERMONT

TDD I

98-05-0136 I DRAWN BY:

I T. TRAN DATE

12/22/97

C:\STAR1\EMC0\EMC01 .DWG FIGURE 1

9 .lentcmber 1998

LEGEND

0 RESIDENCE V CRASS - « — « — » ­ FENCE

4- UONITORING WELL (SCREENED IN OVERBURDEN)

TREES/WOODED

Q

PROPERTY BOUNDARY

5S-GALL0N DRUMS

SITE SKETCH

MITEC 15 COMMERCE STREET

WILLISTON, VERMONT

i ^ H Tetra Tech EM Inc. REGION I SUPERFUND TECHNICAL ASSESSMENT ANO RESPONSE TEAM

TDD f

98-05-0136 DRAWN BY:

T. TRAN RLE NAME:

C:\STARAMrrEC\MITEC2.DWG

DATE

8/20/97

FIGURE 2

The Mitec property is located in Ailing Industrial Park, a commercially zoned area consisting of approximately 20 lots and occupying approximately 34 acres (Figure 3). The Mitec property is located approximately 500 feet southwest of the EMCO property. Environmental Protection Agency (EPA) Comprehensive Environmental Response, Compensation, and Liability Information System (CERCLIS) No. VTD982748477. The Mitec property is located on Lot 15 of the Ailing Industrial Park and is bounded by Commerce Street to the east, the Williston Post Office to the north, the McDonalds Corporation training offices to the southwest, and residential properties on Kirby Lane to the west. Access to the property is restricted only from the northwest by a chain-link fence. A wooden fence on the southwestern side of the property is not attached to the building and, therefore, does not effectively prevent access on to this side of the property [3, p. 1]. A paved area extends from Commerce Street to the front of the building. A parking area occupies a northem extension of this paved area. The front entrance and two large overhead doors are located along the southeastern wall of the building. Grassy areas lie adjacent to the northeast and southwest walls of the building. In addition, a well house is attached to the southwest wall of the building. The well in the well house is capped and is no longer in use; the building is served by public water [3, p. 2; 8, p. 4].

OPERATIONAL AND REGULATORY HISTORY AND WASTE CHARACTERISTICS

The Mitec property was purchased by George and Beatrice Ailing in May 1945. Available file information did not indicate the use of the property prior to 1947. Beginning in 1960, the property was developed and subsequently leased by various firms such as a warehouse and distribution center, a ski pole manufacturing facility, an electroplating facility, and for other unidentified operations. The property is currently occupied by Rozzi Restaurant Supply and Bemie's, a window frame business [3, p. 2; 8, p. 2]. The property is currently owned by the Beatrice Ailing Trust.

From approximately 1965 until 1972, the Sunshine Biscuit Company operated at the building as a warehouse and distribution center. In 1972, Qual Tech began to lease the property for unidentified operations and allegedly created the unlined lagoon on the southwest side of the building to dispose of liquid waste [3, p. 2]. The lagoon was described by the Vermont Agency of Natural Resources (VT ANR) as 15 feet in diameter by 2 feet deep, with an estimated volume of 500 gallons [6, p. 1]. Other sources indicate that the lagoon more closely resembled a hand-dug pit that measured 4 feet in length and in depth, or that it measured 10 feet wide by 2 feet deep [3, p. 2; 8, p. 1]. Qual Tech vacated the property in 1974 [3, p. 2].

From 1974 to 1977, North American Alloys occupied the premises manufacturing ski poles. North American Alloys generated and discharged an undetermined quantity and type of plating rinsewater wastes into the lagoon [3, p. 2]. From 1977 to 1979, Garmont Ski Boots leased the property and operated a warehouse and distribution center for ski boots [3, p. 2].

From 1979 to 1986, Mitec leased the property and operated an electroplating facility on the premises. Between 1979 and 1985, Mitec discharged an undetermined quantity of rinsewaters and sludge wastes to the lagoon. Mitec's discharges included wastewater containing chromium.

9 September 1998

ADAPTED FROM SITE INSPECTION FINAL REPORT. TRCC, JULY 1993; AND SITE INVESTIGATION. BINKERD ENVIRONMENTAU

OCTOBER 1996

A L - 1 2

WMD UPSTREAM SAMPLE

UNNAMED INTERMITTENT STREAM

AUJNGINDUSTRIALPROPERTYBOUNDARY

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WETUNO

=r:z=z=: PAVED ROAD INTERMITTENT STREAM A SURFACE WATER SAMPLE (VT WMD, 1996)

MONrrORING W E U (SCREENED IN OVERBURDEN)

TREES/WOOOEO

GRASSY AREA

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SOIL SAMPLE

SEDIMENT SAMPLE

SAMPLE LOCATION SKETCH ^ ^ B H Tetra Tech EM Inc. MITEC REGION 1 SUPERFUND TECHNICAL ASSESSMENT AND RESPONSE TEAM

TDD I DRAWN BY: DATE 15 COMMERCE STREET 98-05-0136 T. TRAN 12/22/97

WILLISTON, VERMONT HLE NAME:

C:\STARAEMC0\AIUNG2.DWG FIGURE 3

C:\START\MrrEC\MITECFNL.WPD 9 September 1998

cadmium, cyanide, nickel and other industrial solvents associated with electroplating operations [3, p. 2; 4, p. 3; 5, p. 1; 6, p. 3]. After a Mitec employee expressed concem to the Vennont Agency of Environmental Conservation (VT AEC) in March 1982, VT AEC inspected the Mitec facility and grounds. VT AEC found Mitec in violation of hazardous waste regulations for the disposal of chromium-contaminated waste [4, Chronology p. 1].

In January 1984, Mitec ceased discharging wastes to the lagoon and hired Aquatec Inc. (Aquatec) of South Burlington to implement a wastewater treatment system. In March 1984, VT AEC filed suit against Mitec for alleged contamination and submitted a 6610a Administrative Order to Mitec [3, p. 2]. In Spring 1984, wastewater was hauled off-site by New England Marine (NEM), a licensed waste hauler, to a Niagara Falls, New York location [6, p. 1 and 3, p. 2]. In August 1984, Mitec retained J.H. Stuart Associates Inc. (J.H. Stuart) to conduct a subsurface investigation. J.H. Stuart installed monitoring wells MI-1 through MI-9 on the Mitec property. On 12 March 1984, Mitec notified the U.S. Environmental Protection Agency (EPA) of its status as a small quantity hazardous waste generator. However, the facility failed to obtain a permit for the on-site disposal of hazardous wastes [3, p. 3]. During Spring 1985, 30 cubic yards (ycf) of soil from the sides and bottom of the lagoon were removed and transported by NEM, a licensed hauler, to Buffalo, New York [6, p. 2; 4, Chronology p. 1].

J.H. Stuart collected groundwater samples in December 1984, February and June 1985, and July 1986. June 1985 samples were collected from monitoring wells MI-1 through MI-9 to confirm the presence of trivalent and hexavalent chromium in groundwater downgradient of the lagoon. Analytical results from these groundwater sampling activities are discussed in the Groundwater Pathway section of this report.

In 1985, the Vermont Department of Health (VT DOH) sampled eight residential wells west and downgradient of the lagoon [3, p. 3]. VT AEC also installed eleven monitoring wells (AL-1 through AL-11) downgradient of the lagoon and upgradient of the affected residential wells [6, p. 2; 4, Chronology p. 1]. In October 1985, VT AEC performed in situ slug testing to identify hydraulic conductivity in water-saturated soils located downgradient of the lagoon. In January 1986, ten additional groundwater wells (AL-12 to AL-21) were installed by VT AEC east and south of the Mitec property [Chronology p. 2; 6, p. 3]. Analytical results from these groundwater sampling activities are discussed in the Groundwater Pathway section of this report.

In January 1986, VT AEC sued Mitec for remedial and mvestigative expenses related to Mitec's groundwater contamination [3, p. 3]. On-site manufacturing operations ceased in 1986. From 1987 to 1988, Wagner, Heindel and Noyes (WHN), under contract with the Vermont Agency of Natural Resources (VT ANR, previously VT AEC), conducted quarterly sampling of six monitoring wells (MI-8, AL-2, AL-4, AL-5, AL-7, and AL-8) for trichloroethene (TCE) and tetrachloroethene (PCE). Results of this groundwater sampling are discussed in the Groundwater Pathway section of this report.

In March 1987, NUS/FIT completed a Preliminary Assessment (PA) of the Mitec property [3, References p. 1].

9 September 1998

In 1989, under contract with VT ANR, Aquatec hic. (Aquatec) began quarterly air monitoring for VOCs in the basement or lowest levels of six residences located west and downgradient of the property. Results of these air monitoring activities are discussed in the Air Pathway section of this report.

In 1989, a Mitec property representative manually excavated, removed, and backfilled 4 feet of soil from the lagoon area. In 1990, 6 to 12 inches of surface soil over an area of unspecified size were also removed from the northwest side of the property by a property representative [3, p. 3]. Information on the disposal locations of the excavated soil was not available for the 1989 or 1990 removal.

A Screening Site Inspection (SSI) was completed by NUS/FIT in October 1990. The SSI summarized previous investigations at the property.

VT ANR renewed its investigation of the Ailing Industrial Park and Mitec properties in 1995 after analytical results of groundwater testing at Ailing Industrial Park indicated high concentrations of TCE [5, p. 1]. Information on the specific locations of VT ANR's 1995 groundwater sampling is not available. VT ANR identified contaminated groundwater primarily containing TCE that likely originated from (1) a former leaching field located east of the Mitec building, and (2) the former Mitec lagoon [5, p. 2]. VT ANR noted diat the leaching field was abandoned in the mid­1980s when public sewer lines were installed in Ailing Industrial Park. Available file information did not indicate the construction, former use, or size of the leaching field [5, p. 2]. According to VT ANR in 1995, TCE contammated groundwater and undissolved TCE at 30 to 40 feet below ground surface (bgs) flowed east of the Mitec property. VT ANR indicated that the former leaching field is the likely source of this TCE contamination [5, p. 2].

In 1996, the Vermont Department of Environmental Conservation (VT DEC) Waste Management Division (WMD) stated that the contamination originating at the Mitec lagoon also contained PCE, chromium, and cadmium, and that off-site migration of those contaminants had occurred throughout the Ailing Industrial Park property [4, p. iii].

In July 1997, the Roy F. Weston, Inc. (WESTON*) Superfund Technical Assessment and Response Team (START) conducted an on-site reconnaissance of the property. During the on-site reconnaissance, a circular patch of sand approximately 12 feet in diameter was observed. The curcular area is the locatioil of the former lagoon and lies approximately 30 yards from the western comer of the Mitec building [3, p. 2]. No evidence of release was observed by START persoimel in the Mitec building or on the property [8, p. 4]. Window and glass frames, wood molding, sheet metal, iron and plastic piping, wood pallets, spools of electrical wire, a trailer, and restaurant sinks were observed in the yard west of the building. Two empty 55-gallon drums were observed on the northwest side of the Mitec building [8, p. 9]. START also observed sinks, refrigerators, 5-gallon containers of detergent and sanitizer, ovens, fumiture, window frames, glassware, plates, and other table service items m the large, north-facing room within the Mitec building [8, p. 4].

On 17 December 1997, START conducted sediment sampling in the unnamed stream and soil sampling in the unnamed intermittent stream located southeast and east of the Mitec property to

.,^„,.„.,.^^,,„„ ,„op, 7 9 September 1998

evaluate whether a release has occurred to the surface water pathway and the contaminant route [8]. Five sediment, four soil, and two reference samples were collected and analyzed for VOCs, semivolatile organic compounds (SVOCs), pesticides, polychlorinated biphenyl compounds (PCBs), and inorganic elements; Tier n data validation was performed. Results of this sediment and soil sampling are discussed in the Surface Water Pathway and Soil Sampling sections of this report [28; 29; 30]. ^ : .

Table 1 presents identified structures or areas on the Mitec property that are documented or potential sources of contamination, the containment factors associated with each source, and the relative location of each source.

Table 1

Source Evaluation for Mitec

Source Area Containment Factors Spatial Location

Lagoon None Southwest of the Mitec building

Drums None Northwest of the Mitec building

Excavated soil (1985) Removed and disposed off-site Excavated from former lagoon, southwest of the Mitec building

; Leaching field Unknown Southeast of the Mitec building

[5; 8]

Table 2 summarizes the types of potentially hazardous substances which have been disposed, used, or stored on the Mitec property.

Table 2

Hazardous Waste Quantity for Mitec

Quantity Years of Years of Substance or Volume/Area Use/Storage Disposal Source Area

Electroplating 500 gallons 12 12 Lagoon rinsewaters and sludge wastes

[3]

r\START\MITEaMrrECFNL.WPD 9 September 1998

Other potential sources of contamination located within 1-radial mile of Mitec and listed in the CERCLIS or the Resource Conservation and Recovery Information System (RCRIS) are shown in Table 3.

Table 3

CERCLIS and RCRIS Facilities Located within 1-Radial Mile of Mitec

Facility Name RCRIS or CERCLIS Number

EMCO (formerly Ailing Industrial Park) CERCLIS No. VTD982748477

Judge Development CERCLIS No. VXD 108680034

Rossignol Ski CERCLIS No. VTD059018945

Carons East End Auto Body Inc. RCRIS No. VTD00138106O

Carpenters Motor Transport Inc. RCRIS No. VTD5OOOO00828

Champlain Valley Cleaners RCRIS No. VTD982762361

Federal Express Corporation RCRIS No. VTD988366977

Johnson Filaments Inc. RCRIS No. VTD079947180

Haselton Kaulback Corporation RCRIS No. VTD981884927

United Parcel Service RCRIS No. VTD5000000729

GCA Corporation RCRIS No. VTD982543704

Villanti & Sons Printers Inc. RCRIS No. VTD058171869

[31]

No. = Number RCRIS = Resource Conservation and Recovery Information System CERCLIS = Comprehensive Enviromnental Response, Compensation, and Liability Information System

WASTE/SOURCE SAMPLING

In October 1983, VT ANR received an analysis of Mitec's rinsewater and liquid waste. Analytical results indicated cadmiimi and chromium in the liquid waste, and chromium in Mitec's rinsewater [3]. Additional information on analytical results was not available. Data validation and quality control procedures were not documented in available information.

GROUNDWATER PATHWAY

Bedrock beneath the property consists of interbedded limestone marble and dolomitic marble of the Heisenburg Synclinoriiun structure within the Champlain Lowland metasedimentary complex. Regionally, the bedrock contains many faults and fractures and lies approximately 300 feet bgs.

r\<:TART\MrTEOMn'ECFNL.WPD 9 September 1998

Local soil consists of loamy medium to fme sands with ttaces of silt. Overburden materials consist of deltaic deposits. Logs from the installation of monitoring wells indicate that a thick layer of water-saturated sands overlies a silt-clay layer that is found approximately 48 to 50 feet beneath the property. VT ANR reported that shallow groundwater is located between 8 and 10 feet bgs and flows to the southwest [3, p. 4]. It has been reported that normal annual precipitation for Chittenden County, Vermont, is 33.69 inches [23, p. 4].'

All or parts of the following Vermont towns are located within 4-radial miles of the property. Burlington, Essex, Essex Junction, Shelburne, South Burlington, St. George, Williston, and Winooski. Towns located within 4-radial miles of the property obtain public water from surface water intakes located in Lake Champlain [10]. The nearest well is a private residential well located approximately 1.1 miles south of the Mitec property [26]. One public water supply well is located within 4-radial miles of the property. The Williston Fire District Well No. 1 is a bedrock well located 2.5 miles southeast of the property; the well serves an estimated 288 people [25].

According to Frost Associates of Essex, Connecticut, an estimated 1,575 people obtain drinking water from private drinking water wells located within 4-radial miles of the property. Private groundwater supplies within 4-radial miles of the property were estimated using equal distribution calculations of U.S. Census CENTRACTS data identifying population, households, and private water wells for "Block Groups" that lie within or partially within individual radial distance rings of the property [11]. Estimated drinking water populations for the property are summarized in Table 4.

Table 4

Estimated Drinking Water Populations Served by Groundwater Sources Within 4-Radial Miles of Mitec

Total Estimated Radial Distance from Estimated Population Population Served by

Mitec Served by Estimated Population Groundwater Sources (miles) Private Wells Served by Public Wells Widiin the Rin^

i 0.00 to 0.25 0 0 0

> 0.25 to 0.50 16* 0 , 1 6

> 0.50 to 1.00 0 0 0

> 1.00 to 2.00 303 0 303

> 2.00 to 3.00 458 288 746

vcT»pT\urTPr\MITECFNL.WPD 10 9 September 1998

Table 4 (Concluded)

Estimated Drinking Water Populations Served by Groundwater Soiu-ces Within 4-Radial Miles of Mitec

RadiaMitec (miles)

l Distance from Estimated Population Served by

Private Wells Estimated Population

Served by Public Wells

Total Estimated Population Served by Groundwater Sources

Within the Ring

> 3.00 to 4.00 814 0 814

TOTAL 1,591 288 1,879

[11; 25; 26]

* Note: In 1985, six private drinking water wells serving approximately 16 people were sealed as a result of TCE and PCE contamination related to Mitec sources. These residences were consequently connected to the public water supply in June 1985 [5, p. 1; 3, p. 3].

During the START on-site reconnaissance, four overburden monitoring wells (MI-6, MI-1, MI-9, and MI-2) were observed on the property. The stick-up casing from monitoring well MI-6 rises 3.5 feet from the ground surface of the center of the former lagoon; the well casing was unlocked and was covered with half of an aluminum can [3, p. 2]. A second monitoring well (MI-1) is located approximately 50 yards northwest of the building along a row of pine frees, a third (MI-9) is 25 yards north of the building, and a fourth monitoring well (MI-2) is located on the southwest side of the Mitec property [4, Figure 2; 8, p. 3]. All four monitoring wells were observed by START persormel during the on-site reconnaissance and were noted to be in good condition [3, p. 2; 8, p. 4]. Monitoring well MI-2 was observed to be unlocked but covered, and the two wells located north of the building (presumedly MI-1 and MI-9) were sealed withflush-mounted metal casmgs [8, p. 6].

Between 1984 and 1986, 30 overburden monitoring wells (MI-1 through MI-9, and AL-1 through AL-21) were installed by J.H. Stuart and VT ANR at depths of 15 to 52 feet bgs [3, p. 5]. Groundwater samples were collected from selected monitoring wells in December 1984, February, June, and July 1985, and January 1986.

Analytical results of groundwater samples collected by J.H. Stuart from monitoring wells MM through MI-9 from December 1984 to Febmary 1985 indicated elevated concentrations of cadmium [420 parts per billion (ppb)], chromium (3,340 ppb), copper (840 ppb), nickel (100 ppb), and zinc (380 ppb) [3, Attachments E and G].

In 1985, VT ANR began an investigation of the Ailing Indusfrial Park and Mitec properties. The investigation identified groundwater contamination, primarily consisting of TCE, that originated from the Mitec lagoon [5, pp. 1, 2]. A 1995 investigation by VT ANR later revealed that the contaminated groundwater also contained PCE, cadmium, and chromium [4, p. iii].

C;\START\MITEOM!TECFNL.WPD 11 9 September 1998

In June 1985, samples were collected from monitoring wells MI-1 to MI-9. Samples were analyzed by Industrial and Environmental Analysts, Inc. (lEA) to confum the presence of trivalent and hexavalent chromium in groundwater downgradient of the lagoon. Chromium was detected downgradient of the former lagoon in well MI-6 and in wells Ml-5, Ml-7, and Ml-8. Chromium was not detected in the background wells located upgradient of the lagoon [6, p. 2],

During June and July 1985, VT DOH collected groundwater samples from eight private residential drinking water wells located within the shallow aquifer downgradient of the former lagoon; the wells were located approximately 1,000 to 2,000 feet southwest of Mitec on South Brownell and Shunpike Roads. Samples collected on 27 June and 16 July 1985 were analyzed by the VT DOH Laboratory for VOCs and inorganic elements, respectively. Analytical results of groundwater samples indicated elevated levels of TCE and PCE in six of the eight private wells at concentrations considerably higher than those detected in samples collected near the Mitec lagoon [3, p. 7]. Maxunum concentrations of TCE (590 ppb), PCE (12 ppb), and chloroform (13 ppb) were detected in well Nos. 15, 11, and 28, respectively [3, Attachment L]. The detected concentrations of TCE and PCE exceeded maximum contaminant levels (MCLs) of 5 ppb and 7 ppb [3, p. 6; 4, p. 3]. Data validation or quality control procedures were not documented in available information. As a result of the private well contamination, VT DOH sealed existing water supply wells and subsequently connected eight residences to the public water supply by June 1985 [5, p. 1; 3, p. 3]. Elevated concentrations of inorganic substances were not detected in any of the residential wells as of July 1985 [3, Attachment M].

In July 1985, VT ANR installed eleven monitoring wells (AL-1 through AL-11) located downgradient of the lagoon and upgradient of the affected residential wells [6, p. 2; 4, Chronology p. 1]. In October 1985, VT ANR performed in situ slug testing to determine hydraulic conductivity of water-saturated soils located downgradient of the lagoon. Based on the results of tests on monitormg wells AL-1, AL-2, AL-4, AL-7, AL-8, MI-7, and MI-8, VT ANR confirmed the existence of a hydrological coimection between Ailing Industrial Park and the private residences [6, p. 3]. Analytical results of groundwater sampling mdicated elevated concentrations of VOCs m monitoring wells AL-2, AL-4, AL-7, AL-8 and MI-8, located west of the lagoon [6, p. 2; 4, Chronology p. 1].

Analytical results of groundwater samples (MI-4 through MI-9, and AL-1 through AL-9) collected from 1985 to 1988 on the Mitec property indicated elevated concentrations of niunerous VOCs including TCE and PCE [6, p. 2]. Groundwater samples were analyzed by two labs, IE A and VT AEC. Data validation and quality control procedures were not documented in available information. Samples analyzed by lEA in Febmary 1985 were not preserved and were held for approximately one month prior to analysis. Significant losses by microbial degradation of nonchlorinated aromatics may have occurred in samples from wells MI-4, MI-5, MI-6, MI-7, MI-8 and MI-9, according to lab technicians [3, Att. F]. Substances detected in groundwater are consistent with past industrial use and disposal practices at the property. Maximum concentrations of these contaminants are shown in Table 5.

12

Table 5

Maximum Concentrations of VOCs Detected in Groundwater Mitec and Ailing Industrial Park Properties (1985 to 1988)

Concentration Sample Substance (/ig/L) Location Date

Acetone 220 MI-8* 2/85

Benzene 120 MI-8 2/85

Carbon tetrachloride 370 MI-8 6/85

Chloroform 33 MI-4* 2/85

1,2-Dichloroethane 48 MI-8 2/85

1,1-Dichloroethene 53 AL-7 7/85

Ethylbenzene 1,230 MI-8 2/85

Methylene chloride 8.9 MI-4 2/85

Tetrachloroethene (PCE) 1,700 MI-6 2/85

Toluene 2,490 MI-8 2/85

1 Trichloroethane (TCA) 8 MI-5 6/85

Trichloroethene (TCE) 3,300 AL-7 3/87

JCylene 218 MI-8 2/85

[3, p. 5; Att. F, H, I, J, K]

A g/L = micrograms per liter VOCs = Volatile organic compoimds * = Samples were collected in February 1985 and were analyzed by IE A. Samples were not

preserved and were held for approximately one month prior to analysis. Significant losses by microbial degradation of nonchlorinated aromatics may occur in samples within days if not preserved [3, Att. F].

In January 1986, ten additional groundwater wells were installed by VT ANR (AL-12 to AL-21) [4, Chronology p. 2; 6, p. 3]. Analytical results of groundwater samples collected from monitoring wells AL-12 through AL-16 and nearby private drinking water wells indicated that groundwater located directly downgradient of the lagoon contained TCE, chromium, and cadmium [4, Chronology p. 2; 6, p. 3].

WHN, under contract with VT ANR, conducted quarterly groundwater sampling of monitoring wells MI-8, AL-2, AL-4, AL-5, AL-7, and AL-8 for TCE and PCE from March 1987 to 1988.

C:\START\MITEC\MITECFNL.WPD 13 9 September 1998

Field and trip blank samples were collected by WHN, but there is no indication that an upgradient background sample routinely was collected. Samples were analyzed for VOCs using EPA Methods 601 and 602, and for inorganic elements using EPA Method 600 [3, p. 5]. Sample analyses were performed by lEA in 1987 and Endyne, Inc. in 1988 [3, p. 5]. Analytical results indicated maximum concentrations of TCE at 3,300 ppb (AL-7) and PCE at 660 ppb (IE) [6, p. 4]. However, in 1988, WHN reported an increase in PCE concentrations in monitoring well AL-2 (12 ppb in March 1987; 257 ppb in October 1988) [6, p. 4]. Whereas previous sampling had indicated the highest concentrations of TCE and PCE in monitoring well AL-7 in six out of seven sampling events, the 1988 evidence indicated the highest concentrations of PCE and TCE at AL-2, suggesting that the groundwater contamination had moved in a westerly direction towards well AL-2 [6, p. 4].

In 1995, VT ANR renewed its previous investigation of the Ailing Industrial Park and Mitec properties [5, p. 1]. VT ANR identified groundwater contamination primarily containing TCE that likely originated from (1) a former leaching field located east of the Mitec building, and (2) the former Mitec lagoon [5, p. 2], The groundwater also contained PCE, cadmium, and chromium [4, p. iii]. According to VT ANR, it is possible that undissolved TCE flowed to the east at 30 to 40 feet bgs, and that the former leaching field is the likely source of this TCE contamination [5, p. 2; 32].

Based on analytical results from previous groundwater monitoring well sampling conducted on the Mitec property, as well as private drinking water well sampling in the surrounding area, groundwater beneath the property has been impacted by a release of hazardous substances which appears to be attributable to on-site sources. In 1985, six private drinking water wells were found by VT DOH to be impacted by groundwater contamination; the wells were consequently sealed, and the homes were connected to the public water supply in June 1985. To date, no other actions have been taken to address the release to groundwater.

SURFACE WATER PATHWAY

The topography surrounding Mitec is generally flat, with an average elevation of approximately 340 feet above mean sea level (msl) [4, p. 1]. Surface water mnoff from the property migrates overland to the southeast and enters an unnamed stream located on the southeast side of the property. The most upstream probable point of entry (PPE) for the property is located roughly 1,000 feet southeast of the Mitec property, in the unnamed sfream. The uimamed stream flows southwest at an estimated rate of 1.8 cubic feet per second (cfs) [15]. Roughly 1.25 miles downstream of the PPE, the unnamed stream joins Muddy Brook. Muddy Brook flows to the north at 36.5 cfs and joins Winooski River roughly 2.5 miles downstream of the PPE [2; 9, p. 13; 16]. The flow rate of Winooski River is estimated to be 2,204 cfs [17]. The 15-niile downsfream pathway terminates in Winooski River, roughly 3 miles upstream of Lake Champlain [3, p. 13; 18]. Information regarding waterbodies located along the 15-mile downstream pathway is provided in Table 6.

r.\<:TART\MrrEnMITECFNL.WPD 1 4 9 September 1998

Table 6

Surface Water Bodies Along the 15-Mile Downstream Pathway from Mitec

Length of Wetland Surface Length of Reach Flow Characteristics Frontage

1 Water Body Descriptor^ (miles) (cfs)^ (miles)

Unnamed Stream Minimal Stream 1.25 1.8 2.5

Muddy Brook Small to Moderate 2.5 36.5 4.7 Stream 1

[ Winooski River Large Stream to River 11.25 2,204 2.9

' Minimal stream < 10 cfs. Small to moderate stream 10-100 cfs. Moderate to large stream > 100-1,000 cfs. Large stream to river > 1,000-10,000 cfs. Large river > 10,000-100,000 cfs. Very large river > 100,000 cfs. Coastal tidal waters (flow not applicable). Shallow ocean zone or Great Lake (flow not applicable). Moderate depth ocean zone or Great Lake (flow not applicable). Deep ocean zone or Great Lake (flow not applicable). Three-mile mixing zone in quiet flowing river 10 cfs or greater.

'' Cubic feet per second.

[2; 9, p. 13; 15; 16; 17; 18; 19; 20; 21; 22]

The Champlain Water District (CWD) of South Burlington, Vermont, draws surface water from Lake Champlain and distributes it to Williston and the surrounding towns of Colchester, Essex Junction, and South Burlington. Lake Champlain is located more than 15 miles downsfream from the property. All residents of these towns, with the exception of residents south of Interstate 89 in Williston, are served by or have access to the CWD water supply.

No drinking water intakes are located along the 15-mile downstream surface water pathway [3, p. 12]. It is assumed that all water bodies along the 15-mile downsfream pathway are fisheries. Species found m Muddy Brook include minnows and suckers [23, p. 4]. Winooski River is used chiefly for recreational fishuig and boating [3, p. 13]. Accordmg to the U.S. Fish and Wildlife Service, there are 10.1 miles of wetland frontage located along the 15-mile downstream pathway [19; 20; 21; 22]. According to the VT ANR Nongame and National Heritage Program, habitats are used by two State-designated threatened species along the 15-mile downstream pathway [12]. Sensitive envfronments along the surface water pathway are shown in Table 7.

C:\ST AR'nMITEC\MITECFNL.WPD 15 9 September 1998

Table 7

Sensitive Environments Along the 15-Mile Downstream Pathway from Mitec

Sensitive Sensitive Downstream Flow Rate Environment Environment Water "' Distance from PPE at Environment

[ Name Type Body (miles) (cfs)'

Unnamed stream State-designated area for Unnamed Oto 1.25 1.8 protection and stream maintenance of aquatic life under the Clean Water Act

Unnamed sueam Wetlands, 2.5 frontage Unnamed Oto 1.25 1.8 miles stream

Unnamed stream Habitat known to be used Unnamed Oto 1.25 1.8 by a State-designated stream threatened species (two occurrences)

Muddy Brook Wetlands, Muddy Brook 1.25 to 2.5 36.5 4.7 frontage miles

Winooski River Wetlands, Winooski 2.5 to 15 2,204 2.9 frontage miles River

' Cubic feet per second

[9, p. 18; 17; 19; 20; 21; 22; 12]

In 1995, Mr. Frank Ailing removed 1 inch of soil from an area of unspecified size in the unnamed intermittent stream; the soil was shipped off-site by Pollution Solutions, Inc. Based on observations made during the START on-site reconnaissance conducted in July 1997, and conversations with Mr. Ailing, START estimated that the volume of excavated soil was 2 yd [13].

From May to September 1996, surface water samples were collected by Binkerd Environmental under confract with VT ANR from the unnamed intermittent sfream and the unnamed stream located on the southeast side of Ailing Indusfrial Park. Sample station U-Trib 10, the station located closest to the permanent water body, was found to have elevated concenfrations of TCE (310 to 410 ppb) and cis-1,2-dichloroethene (cis-1,2-DCE; 43 to 100 ppb). Substances detected in surface water and sediment are consistent with past mdustrial use and disposal practices at the Mitec property. Samples were collected at six other stations along the unnamed intermittent sfream which flows to the southeast of Ailing Indusfrial Park [24, p. 22]. According to VT ANR, it is possible that TCE contaminated groundwater and undissolved TCEflowed to the east of Mitec in groundwater at depths of 30 to 40 feet bgs, and furthermore, that the TCE detected in surface water samples may have migrated to the intermittent stream via groundwater [5, p. 2; 32].

C;\START\MITEC\MITECFNL.WPD 16 9 September 1998

On 17 December 1997, START conducted sediment samplmg in die unnamed stream located east of the property to evaluate whether a release has occurted to surface water. Five sediment and two reference samples were collected in the unnamed stream. Samples SD-01 through SD-06 were analyzed for VOCs, SVOCs, pesticides, PCBs, and inorganic elements. Sample SD-07 was analyzed for inorganic elements only. Trip blanks; equipment rinsate blanks, and field duplicates were collected and Tier II data evaluation was perfonned [28;-29; 30]. Table 8 provides the locations and descriptions of sediment samples collected by START on 17 December 1997.

Table 8

Sample Summary: Mitec Sedunent Samples Collected by START on 17 December 1997

Sample Traffic Time Sample Location No. Report No. (hrs) Remarks Depth Sample Source

MAIRIX: Sediment

SD-01 DAFJ70 0820 Grab 0 to 4 Sediment sample from wetlands in unnamed inches stream, 210 feet at N 8° W of southwest

comer of Building No. 40; brownish gray silty clay with trace organic matter; FID reading (OVA) = 0 units above background.

SD-02 DAFJ71 0835 Grab Oto 8 Sediment sample from wetlands in unnamed inches stream, 50 feet at N 61° W and upstream of

SD-01; gray silty clay with trace organic matter; FID reading (OVA) = 3 units above backgrotmd.

SD-03 DAFJ72 1050 Grab 6 to 12 Sedunent sample from wetlands in unnamed inches stream, 195 feet at N 101° W of northeast

comer of Building No. 40; dark brown silt with trace sand and trace organic debris; FID reading (OVA) = 0 units above background.

SD-04 DAFJ73 1100 Grab 4 to 10 Sediment sample from the PPE in wetlands mches in unnamed stream, 64 feet at N 177° W and

upstream of SD-03; gray sandy clay with trace gravel; FID reading (OVA) = 0 units above background.

SD-05 DAFJ74 1100 Grab 4 to 10 Duplicate of SD-04 collected for quality inches control (MS/MSD).

SD-06 DAFJ75 0935 Grab Oto 6 Sediment sample from wetlands east of inches uiinamed stream, taken as a reference, 430

feet at N 79° W of northeast corner of Building No. 40; dark brown to black .sandy silt with trace organic debris; FID reading (OVA) = 0 units above background.

r\.<;TART\MIT£aMITECFNL.WPD 17 9 September 1998

Table 8 (Concluded)

Sample Summary: Mitec Sediment Samples Collected by START on 17 December 1997

Sample Location No.

Traffic Report No.

Time (hrs) Remarks

Sample Depth Sample Source

SD-07 DAFJ76 0940 Grab Oto 6 inches

Sediment sample from wetlands east of unnamed stream, taken as a reference, 410 feet at N 77° W of northeast comer of Building No. 40; dark brown to black sandy silt with trace organic matter; FID reading (OVA) = 0 units above background. |

1 MATRIX: Aqueous j

RB-01 DAFJ81 1430 Grab NA Sediment sampling equipment rinsate blank sample, collected for quality control.

1 TB-01 DAFJ82 0700 Grab NA Trip blank collected for quality control.

1 Matrix: Perfonnance Evaluation Sam pies 1

PE-0019889 DAFJ83 0700 Grab NA Aqueous Performance Evaluation sample for low to medium cyanide.

PE-TTI260 DAFJ84 0700 Grab NA Solid Performance Evaluation sample for • low to medium metals.

PE-TT03077 DAFJ85 0700 Grab NA Solid Performance Evaluation sample for low to medium PCBs.

PE-0009215 DAFJ86 0700 Grab ' NA Aqueous Perfonnance Evaluation sample for low to medium VOCs.

PE-0012238 DAFJ87 0700 Grab NA Aqueous Performance Evaluation sample for low to medium SVOCs.

PE-0029418 DAFJ88 0700 Grab NA Aqueous Perfonnance Evaluation sample I for low to medium pesticides/PCBs.

[28; 29; 30]

MS/MSD = Matrix Spike/Matrix Spike Duplicate NA = Not applicable PCB = Polychlorinated biphenyls VOCs = Volatile organic compounds SVOCs = Semivolatile organic compounds PPE = Probable point of entry bgs = Below ground surface hrs = Hours N = North W = West

C:\START\MrTEC\MrrECFNL.WPD 18 9 September 1998

Table 9 is a summary of organic compounds and inorganic elements detected through Contract Laboratory Program (CLP) analyses of START sedunent samples. For each sample location, a compound or element is listed if it is detected at three times or greater than the reference sample concentrations (SD-06 and SD-07). However, if the compound or element is not detected in the reference sample, the reference sample's quantitation limit (SQL) (for organic analyses) or sample detection lunit (SDL) (for inorganic analyses) is used ais the reference value. These compounds or elements are listed if they occurred at a value equal to or greater than the reference sample's SQL or SDL and are designated by their approximate relative concentration above these values.

Complete analytical results of START sediment samples including quantitation and detection limits are presented in Attachment A. Sample results quantified with a "J" on analytical tables are considered approximate because of limitations identified during CLP data validation. In addition, organic sample results reported at concentrations below quantitation limits and confirmed by mass spectrometry are also qualified by a "J" and considered approximate.

Table 9

Summary of Analytical Results Sediment Sample Analysis for Mitec

Sample Location

Compound/ Element

Sample Concentration

Reference Concentration Comments

SD-02 (DAFJ71)

VOCs

Acetone 52 J pig/kg 15 UJ Mg/kg 3.5 X SQL

INORGANICS

Arsenic 4.4 mg/kg 3.2 U mg/kg 1.4 X SDL

SD-03 (DAFJ72)

Cadmium

VOCs

Acetone

0.16 • •

120

mg/kg

J Mgl g

0.16

15

U mg/kg

UJ Mg/kg

1 X SDL

8 X SQL

INORGANICS

Arsenic 7.9 mg/kg 3.2 U mg/kg 2.5 X SDL

Cadmium 0.60 mg/kg 0.16 U mg/kg 3.8 X SDL

SD-04 (DAFJ73)

INORGANICS

Arsenic 3.6 mg/kg 3.2 U mg/kg 1.1 X SDL

SD-05 (DAFJ74)

SVOCs

Bis(2-ethylhexyl)phthalate 560 J Mg/kg 480 U Mg/kg 1.2 X SQL

INORGANICS

Arsenic 3.6 mg/kg 3.2 U mg/kg 1.1 X SDL

[28; 29; 30]

C:\START\MITEC\MITECFNL.WPD 19 9 September 1998

Table 9 (Concluded)

Summary of Analytical Results Sediment Sample Analysis for Mitec

J - = Quantitation is approximate due to limitations identi fied during the quality control review U = Indicates the sample was analyzed but not detected and reports the detection value UJ = The reported quantitation limits are qualified estimated mg/kg = Milligrams per kilogram Mg/kg = Micrograms per kilogram VOCs = Volatile organic compounds SQL = Sample Quantitation Limit SDL = Sample Detection Limit

Analytical results from sediment samples collected in the unnamed stream (SD-01 through SD-07) on 17 December 1997 indicated elevated concentrations of organic and inorganic substances that exceeded three times the reference sample concentrations. Concenfrations of arsenic (7.9 mg/kg), acetone (120 Mg/kg), and cadmium (0.60 mg/kg) were detected in sample SD-03, and elevated concentrations of bis(2-ethylhexyl)phthalate (560 J A g/kg) and arsenic (3.6 mg/kg) were detected in sample SD-05 [28; 30]. There was a major impact on data usability due to poor performance evaluation (PE) sample action. Non-detected results for bromodichloromethane, trichloroethene, 2,4-dinitrotoluene, 2-chloronaphthalene, hexachlorocyclopentadiene, heptachlor, and aldrin were rejected (R) due to PE sample actions [28]. Substances detected in sediment samples are consistent with past mdustrial use and disposal practices on the Mitec property. It is possible that substances detected in sedunent samples SD-03 and SD-05 migrated from the Mitec property via surface water runoff or via groundwater.

START performed sedunent sampling as part of the Mitec property SIP. Based on START analytical results and results of previous sampling activities conducted on the property, a release of hazardous substances to the nearby unnamed stream has been noted from on-site sources. As a result of the release, a wetlands, a CWA-protected water body, and a fishery have been impacted. No other sensitive environments are known or suspected to have been unpacted. In 1995, an estimated 2 yd of soil were removed from the unnamed intermittent stream by Mr. Frank Ailing and shipped off-site by Pollution Solutions, Inc. To date, no further actions have been taken to address the release to the surface water pathway.

SOIL EXPOSURE PATHWAY

The nearest residence is located 400 feet north of the Mitec building and approximately 300 feet north of the Mitec property [8, p. 6]. There are five full-time workers at the property. The nearest school or day-care facility is the Allen Brook Elementary School, located 2.1 miles east of the property. No terrestrial sensitive environments are located partially or wholly on the property [12]. According to Frost Associates, an estimated 1,376 people reside within 1-radial mile of the property [8, p. 2].

C:\START\MITEC\MrrECFNL.WPD 2 0 9 September 1998

During Sprmg 1985, 30 yd of soil from the sides and bottom of the lagoon were removed and fransported as hazardous waste by NEM to Buffalo, New York [6, p. 2; 4, Chronology p. 1]. Soil samples were collected by J.H. Smart during the installation of monitoring wells MI-I through MI-9 on the Mitec property in December 1984 and July 1985. Soil collected from borings of the wells was analyzed for select heavy metals and cyanide using Extraction Procedure (EP) toxicity analytic techniques. Elevated levels of total chromiumX760ppb) and hexavalent chromium (620 ppb), copper, nickel, and zinc were observed [3, p. 6 and Attachment A].

In 1989, a Mitec property representative manually excavated, removed, and backfilled 4 feet of soil from the lagoon area. The material used for backfillmg was not specified in file information. In 1990, 6 to 12 inches of surface soil over an unspecified area were also removed from the northwest side of the property by a property representative [3, p. 3]. Information on the disposal locations of the excavated soil was not available for the 1989 or 1990 removal.

On 17 December 1997, START conducted surficial soil sampling in the unnamed intermittment stream located east of die Mitec property to evaluate the contaminant route [8]. Four soil samples were collected in the unnamed intermittent stream. Samples SS-01 through SS-04 were analyzed for VOCs, SVOCs, pesticides, PCBs, and inorganic elements. Trip blanks and equipment rinsate blanks were collected and Tier II data evaluation was performed. Table 10 provides die locations and descriptions of soil samples collected by START on 17 December 1997 [28; 29; 30].

Table 10

Sample Summary: Mitec Soil Samples Collected by START on 17 December 1997

Sample Traffic Time Sample Location No. Report No. (hrs) Remarks Depth Sample Source

(hp.s)

MAIRIX: Soil

SS-01 DAFJ77 1145 Grab Oto 8 Soil sample from unnamed intermittent inches stream; 84 feet at N 60° W of southeast

comer of Building No. 30, near the retention basin, less than 1 foot from sample location U-Trib 7; red-rusty surface, gray clay with sand, white 1-inch gravel, and organic debris; FID reading (OVA) = 0 units above background.

58-02 DAFJ78 1210 Grab Oto 6 Soil sample from unnamed iiuermittent inches stream; 104 feet at N 52° W of northeast

comer of Building No. 14; light brown sand with trace silt; FID reading (OVA) = 80 uiiits above background.

C:\START\MrrEC\MITECFNL.WPD 21 9 September 1998

Table 10 (Concluded)

Sample Summary: Mitec Soil Samples Collected by START on 17 December 1997

Sample Traffic Time Sample Location No. Report No. (hrs) Remarks Depth Sample Source

SS-03 DAFJ79 1225 Grab Oto 6 Soil sample from unnamed intermittent inches stream; 94 feet at N 37° W of nonheasi

comer of Building No. 10; light brown sand with trace silt; FID reading (OVA) = 0 units above background.

SS-04 DAFJ80 1245 Grab Oto 6 Soil sample from imnamed intermittent inches stream; 47 feet at N 40° W of monitoring

well AL-12; light brown sand and gray clay; FID reading (OVA) = 0 units above background.

[23; 24; 25]

Table 11 is a summary of organic compounds and inorganic elements detected through CLP analyses of START soil samples. For each sample location, a compound or element is listed if it is detected at three times or greater than the reference sample concenfration (SS-03). However, if the compound or element is not detected in the reference sample, the SQL or SDL is used as the reference value. These compoimds or elements are listed if they occurred at a value equal to or greater than the reference sample's SQL or SDL and are designated by their approximate relative concentration above these values.

Table 11

Summary of Analytical Results Soil Sample Analysis for Mitec

Sample Compotmd/ Sample Reference Location Element Concentration Concentration Comments

SS-01 VOCs (DAFJ77)

1,2-Dichloroethene 130 J Mg/kg 10 U //g/kg 13 X SQL

INORGANICS

Calcium 10,800 mg/kg 1,540 mg/kg 7.0 X Ref

Zinc 47 mg/kg 15 mg/kg 3.1 X Ref

C.\START\M1TEGMITECFNL.WPD 22 9 September 1998

Table 11 (Concluded)

Summary of Analytical Results Soil Sample Analysis for Mitec

Sample Compound/ Sample Reference Location Element Concentration Concentration Comments

SS-04 VOCs (DAFJ80) Acetone 23 J /. g/kg 10 UJ /.zg/kg 2.3 X SQL

INORGANICS !

Barium 48.7 mg/kg 7.4 mg/kg 6.6 X Ref

Copper 35.1 J mg/kg 8.4 mg/kg 4.2 X Ref

Cyanide 0.95 J mg/kg 0.62 UJ mg/kg 1.5 X SDL

[28; 29; 30]

Analytical results from soil samples collected in the unnamed intermittent stream indicated elevated concentrations of organic substances and metals that exceeded three times the reference sample concentration (SS-03). Concentrations of 1,2-dichloroethene (1,2-DCE; 130 Mg/kg), calcium (0.60 mg/kg), barium (48.7 mg/kg), copper (35.1 mg/kg), acetone (23 J jug/kg) and zmc (47 mg/kg) were detected m samples SS-01 and SS-04 [28; 30]. There was a major impact on data usability due to poor PE sample action. Non-detected results for bromodichloromethane, TCE, 2,4-dmifrotoluene, 2-chloronaphthalene, hexachlorocyclopentadiene, heptachlor, and aldrin were rejected (R) due to PE sample actions [28].

Substances detected in soil are consistent with past industrial use and disposal practices on the Mitec property. Durmg previous mvestigations, copper, zinc, cyanide, and acetone were detected in groundwater samples collected on the Mitec property [3, p. 5]. Substances detected in soil samples SS-01 and SS-04 were not detected in sedunent samples SD-01 through SD-07. Based on surficial topography of the area, it is not clear whether substances found in samples SS-01 and SS-04 migrated overland from sources on the Mitec property. The overland distance from Mitec sources and the soil sample locations is approximately 500 feet. However, it is possible that these substances migrated overland or via groundwater from sources on the Mitec property.

Based on START analytical results and analytical results from previous surficial soil sampling events, a release of hazardous substances to surficial soils located on and near the Mitec property has been documented. It is likely that substances detected in surficial soils located on and near the property are related to on-site sources. Based on the distance to the nearest residence (approximately 400 feet) and lack of public use of the property, no impacts to residential populations are known or suspected and potential impacts to residential populations are limited.

C:\START\MITEC\MITECFNL.WPD 23 9 September 1998

AIR PATHWAY

The nearest residence is located 400 feet north of the Mitec building and 300 feet north of the Mitec property. There are five full-time workers on the property. The nearest school or day-care facility is the Allen Brook Elementary School, located 2.1 miles east of the property [8, p. 6]. Air sampling has not been performed on the property. According to Frost Associates, the estimated population within 4-radial miles of the property is 32,170 [11]. The population within 4-radial miles of the property is summarized in Table 12.

Table 12

Estimated Population Within 4-RadiaI Miles of Mitec

Radial Distance from Mitec (miles) Estimated Population

^ 0.00 to 0.25 102

> 0.25 to 0.50 306

> 0.50 to 1.00 963

> 1.00 to 2.00 3,340

> 2.00 to 3.00 10,384

> 3.00 to 4,00 17,075

TOTAL 32,170

[11]

Sensitive environment targets for the air pathway include wetlands located within 4-radial miles of the property [19; 20; 21; 22]. According to the VT ANR Nongame and National Heritage Program, habitats used by 15 State-designated threatened species, one State-designated endangered species, and one Federally-designated threatened species are located within 4-radial miles of the property [12]. Sensitive environments within 4-radial miles of sources are shown m Table 13.

C:\START\M1TEC\MITECFNL.WPD 24 9 Seplember 1998

Table 13

Sensitive Environments Located Within 4-Radial Miles of Mitec

1 Radial Distance from Mitec (miles) Sensitive Environment/Species (stams)

i 0.00 to 0.25 Wetlands (6 acres) |

> 0.25 to 0.50 Wetlands (1 acre)

> 0.50 to 1.00 Wetlands (35 acres)

> 1.00 to 2.00 Wedands (120 acres)

> 2.00 to 3.00 Wetlands (195 acres)

Habhat known to be used by a State-designated threaten species (3 occurrences)

> 3.00 to 4.00 Wetlands (330 acres)

Habitat known to be used by a State-designated threatened species (12 occurrences)

Habitat known to be used by a State-designated 1 endangered species (1 occurrence)

Habitat known to be used by a Federally­1 designated threatened species (I occurrence)

[19; 20; 21; 22]

In 1989, under confract with VT ANR, Aquatec began quarterly air monitoring for VOCs in the basements or lowest levels of six residences located west and downgradient of the property. An ambient air sample was also taken at the Mitec facility as a control sample. VT DOH reported that the residences were older homes and were located in an area with a shallow water table [6, p. 4]. TCE, PCE and 1,2-DCE were detected in indoor air samples from all six residences with the highest concenfration as follows: TCE, 3 ppb; PCE, 5.3 ppb; and 1,2-DCE, 0.1 ppb [4, Table 5]. VT DOH stated that these VOC concentrations posed no significant risk [6, p. 4].

An sampling m February and March 1990 mdicated that five of the six residences had decreased concenfrations of contammants over the course of the year [3, p. 7; 6, p. 7]. The sixth residence, reporting the highest increase in TCE (3 ppb), was investigated by The Johnson Company Inc. (Johnson) in December 1996. The sump pump drainage system located at this residence was identified by Johnson as the likely pathway through which VOCs could enter the basement [6, p. 5]. The sump pump system was sealed in the summer of 1997, and a follow-up air sample showed a slight decrease m TCE within this residence [14]. Substances detected in indoor air samplmg are consistent with past mdustrial use and disposal practices at the Mitec property. Based on available information, these substances may be attributable to a release to the groundwater pathway [4, p. 17].

C;\START\MrrEC\MrrECFNL.WPD 25 9 September 1998

One laboratory qualitative an sample was collected on the Mitec property m 1989 as a control sample for quarterly uidoor an monitoring conducted in nearby residences. No other laboratory qualitative air samples are known to have been collected from the Mitec property. Based on the available data, no release of hazardous substances to the ambient an from on-site sources is known or suspected to have occurred. No significant impacts to nearby residential populations or sensitive environments are known or suspected.

C.VSTARTiMITEOMrrECFNL.WPD 2 6 9 Seplember 1998

SUMMARY

The Mitec property is located at 15 Commerce Street in Williston, Chittenden County, Vermont, latitude 44° 27' 09.3' nordi and longitude 73° 07' 17.0' west, as measured from the center of the property. The property occupies 1 acre and includes one 6,000 square foot (ff) building. The property is located on Lot 15 of the Ailing Industrial Pai:k, a'commercially zoned area consisting of approxunately 20 lots and occupying approximately 34 acres. The Mitec property was originally purchased by George and Beatrice Ailing in May 1945 and was undeveloped until 1960. Beginning in 1960, the property was developed and subsequently leased by various firms as a warehouse and distribution center, a ski pole manufacmring facility, an electroplating facility, and other unidentified operations. From 1979 to 1986, the Mitec property was used to manufacuire electronic and microwave components involving an electroplating operation with chemical treatment, acid wash, and a water rinse. From 1972 to 1985, Mitec and previous occupants used an unlined lagoon to dispose of liquid wastes. The property is currently occupied by Rozzi Restaurant Supply and Bemie's, a window frame business, and is currently owned by the Beatrice Ailing Trust.

Accordmg to available file rnformation, Qual Tech leased the Mitec property from 1972 to 1974 for unidentified operations and allegedly created the unlined lagoon on the southwest side of the buildmg to dispose of liquid waste. The lagoon was described by the Vermont Agency of Namral Resources (VT ANR) as 15 feet in diameter by 2 feet deep, with an estimated volume of 500 gallons. Other sources indicate that the lagoon more closely resembled a hand-dug pit that measured 4 feet in length and in depth, or that it measured 10 feet wide by 2 feet deep. Qual Tech vacated the property in 1974. From 1979 to 1985, Mitec discharged an undetermined quantity of rinsewaters and sludge wastes to the lagoon containing chromium, cadmium, cyanide, nickel, and other contaminants associated with industrial solvents. On-site manufacturing ceased in 1986.

Towns located within 4-radial miles of the property obtain public water from Lake Champlain [10]. The nearest well is a private residential well located approxunately 1.1 miles south of the property [26]. One public water supply well is located within 4-radial miles of the property. The Williston Fire District Well No. 1 is a bedrock well located 2.5 miles southeast of the property serving an estunated 288 people.

Between 1984 and 1986, 30 groundwater monitoring wells (MI-1 through MI-9, and AL-1 through AL-21) were installed by J.H. Stuart and VT ANR at depths of 15 to 52 feet below ground surface (bgs). Analytical results of groundwater samples collected by J.H. Stuart from monitoring wells MI-1 to MI-9 from December 1984 to February 1985 indicated elevated concentrations of cadmium, chromium, copper, nickel, and zinc. In 1985 and 1986, the Vermont Department of Health (VT DOH) sampled groundwater monitoring and residential wells located west and downgradient of the lagoon. Analytical results of this sampling indicated the presence of frichloroethene (TCE), tefrachloroethene (PCE), chromium, and cadmiiun in groundwater located downgradient of the lagoon.

In 1987 and 1988, Wagner, Heindel and Noyes (WHN), under confract with VT ANR, began quarterly groundwater sampluig of six monitoring wells. Analytical results indicated maximum

C;\START\MITEC\MITECFNL.WPD 2 7 9 September 1998

concentrations of TCE [3,300 parts per billion (ppb); AL-7], and PCE (660 ppb; AL-4). hi 1995, VT ANR identified groundwater contamination primarily containing TCE diat likely originated from (1) a former leaching field located east of the Mitec building, and (2) the former Mitec lagoon. The contaminated groundwater also contained PCE, cadmium, and chromium. According to VT ANR, it is possible that undissolved TCE flows to the east above the bedrock surface.

Surface water runoff from die property migrates overland to the southeast and enters an unnamed stream located on die southeast side of the property. The most upstream probable point of entry (PPE) for the property is located roughly 1,000 feet southeast of the Mitec property in the unnamed stream, which flows southwest into Muddy Brook, then north into Winooski River roughly 2.5 miles downstream of the PPE. Muddy Brook and Winooski River are both fisheries; the latter is used chiefly for recreational fishing and boating. According to the U.S. Fish and Wildlife Service, 10.1 miles of wetlands frontage are located along the 15-mile downstream pathway. According to the VT ANR Nongame and National Heritage Program, habitats are used by two State-designated threatened species along the 15-mile downstream pathway.

On 17 December 1997, the Superfund Technical Assessment and Response Team (START) conducted sediment sampling in the unnamed stream located east of the property. Analytical results of sediment samples SD-01 through SD-07 indicated elevated concentrations of organic and inorganic substances that exceeded three times the reference sample concentrations. Concentrations of arsenic [7.9 milligrams per kilogram (mg/kg)], acetone [120 micrograms per kilogram C^g/kg)], and cadmium (0.60 mg/kg) were detected in sample SD-03, and elevated concentrations of bis(2-ethylhexyl)phthalate (560 J Mg/kg) and arsenic (3.6 mg/kg) were detected in sample SD-05.

The nearest residence is located 400 feet north of the building and approximately 300 feet north of the property. There are five full-time workers at the property. The nearest school or day-care facility is the Allen Brook Elementary School, located 2.1 miles east of the property. No terrestrial sensitive environments are located partially or wholly on the property. According to Frost Associates, an estunated 1,376 people reside within 1-radial mile of the property.

During Spring 1985, 30 cubic yards (yd ' of soil from the sides and bottom of die lagoon were removed and fransported as hazardous waste by NEM to Buffalo, New York. In 1984 and 1985, analytical results from soil samples collected from soil borings of monitoring wells MI-1 through MI-9 by J.H. Stuart mdicated elevated concenfrations of chromium, copper, nickel, and zinc. In 1989, a Mitec property representative manually excavated, removed, and backfilled 4 feet of soil from the lagoon area, and six to 12 inches of surface soil were also removed from the northwest side of the property in 1990. Information on the disposal locations of the excavated soil was not available.

On 17 December 1997, START conducted surficial soil sampling (SS-01 through SS-04) east of the Mitec property in the unnamed mtermittent sfream. Analytical results of soil samples SS-01 through SS-04 indicated elevated concentrations of organic substances and metals that exceeded three times the reference sample concenfrations. Maximiun concentrations of 1,2-dichloroethene (1,2-DCE; 130 /^g/kg), calcium (0.60 mg/kg), barium (48.7 mg/kg), copper (35.1 mg/kg), acetone

C:\START\M1TEC\M1TECFNL.WPD 2 8 9 September 1998

(23 J Mg/kg) and zinc (47 mg/kg) were detected in samples SS-01 and SS-04.Substances detected m soil are consistent with past mdustrial use and disposal practices on die Mitec property. During previous investigations, copper, zmc, cyanide, and acetone were detected m groundwater samples collected on the Mitec property. Substances detected in soil samples SS-01 and SS-04 were not detected in sediment samples SD-01 through SD-07. Based on surficial topography of the area, ir is not clear whether substances found in samples SS-^1 and SS-04 migrated overland from sources on the Mitec property. However, it is possible that these substances migrated overland or via groundwater from sources on the Mitec property.

Sensitive envfronmental targets for the air pathway include approximately 687 acres of wetlands located within 4-radial miles of the Mitec property. According to the U.S, Environmental Protection Agency (EPA) Rare and Endangered Species Report, 15 State-designated threatened species, one State-designated endangered species, and one Federally-listed threatened or endangered species are located within 4-radial miles of the property. According to Frost Associates, the estunated population within 4-radial miles of the property is 32,170.

In 1989, under contract with VT ANR, Aquatec began quarterly air monitoring for VOCs in the basements or lowest levels of six residences located west and downgradient of the property. TCE, PCE and 1,2-DCE were detected in indoor air samples from all six residences with the highest concentration as follows: TCE, 3 ppb; PCE, 5.3 ppb; and 1,2-DCE, 0.1 ppb. VT DOH stated that these VOC concentrations posed no significant risk.

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MITEC REFERENCES

[I]

-

EPA (United States Environmental Protection Agency).Environmental Responsibility, Compensation and Liability

(CERCLIS) Data Base. Printout dated 1 September-, ­

1995. Comprehensive Act Information System

[2] USGS (United States Geological Survey). Photo Revised 1987.Quadrangle, 7.5 Minute Series, 1:24,000 Scale (topographic).

Essex Junction, Vennont

[3] NUS Corporation Field Investigation Team (NUS/FIT). 1990. Site Inspection, Final Report, Mitec, Williston, Vermont, TDD No. Fl-8904-04. October.

[4] Inchcape Testing Services.Vermont. January.

1996. Summary Report, Ailing Industrial Park, Williston,

[5] VT ANR (Vermont Agency of Namral Resources). 1996. Factsheet, Summary of the Environmental Investigation of the Ailing Industrial Park, Williston, Vermont.

[6] Guere, Linda. (VT ANR). 1990. Synopsis Memo to EMCO file. 9 February.

[7] Behrsing, Joel (The Johnson Company, Inc.). 1996. Letter to Mr. Michael Smith (VT ANR), RE: Indoor Air Contamination, JCO No. 1-2277-3. 18 December.

[8] START (Superfund Technical Assessment and Response Team).Logbook. Mitec, TDD No. 98-05-0136.

1997 (Issued). Field

[9] TRCC (TRC Companies, Inc.) 1993.Park, TDD No. 9107-11-ATS. July.

Site Inspection, Final Report, Ailing Industrial

[10] Klein, Andrew (START). 1997.TDD No. 97-02-0027. 8 April.

Project Note, RE: Public Water Sources. Mitec,

[II] Frost Associates.TDD No. 97-02-0027.

1997. 26 April.

CENTRACTS Population Data Report, Mitec,

[12] Marshall, Everett (VT ANR Nongame and Namral Heritage Program). 1997. Letter to Mr. Andrew Klein (START) RE: Federal and State Endangered Species and Significant Namral Communities, Mitec and Ailing Industrial Park sites. 7 May.

[13] START (Superfund Technical Assessment and Response Team).Logbook. EMCO, TDD No. 98-05-0156.

1997 (Issued). Field

[14] Schiller, Alyson (START). Record of Telephone Conversation with Mr. Michael Smith (VT ANR), RE: Mitec - Update on Sampling, TDD No. 97-02-0027. 3 September.

C;\START\MITEaMITECFNL.WPD 9 September 1998

MITEC REFERENCES (Continued)

[15] Klein, Andrew (START). 1997. Project Note, RE: Flow Rate of Unnamed Stream. Mitec, TDD No. 97-02-0027. 5 August..

[16] USGS (United States Geological Survey). Photo Inspected 1987. Burlington, Vermont Quadrangle, 7.5 Minute Series, 1:24,000 Scale (topographic).

[17] Klein, Andrew (START). 1997. Project Note, RE: Flow Rate of Winooski River. Mitec, TDD No. 97-02-0027. 8 April.

[18] USGS (United States Geological Survey). Photo Revised 1987. Colchester, Vermont Quadrangle, 7.5 Minute Series, 1:24,000 Scale (topographic).

[19] Tran, Thomas (START). 1997. Project Note, RE: Wetlands Map - Areas and Frontage Distance. Mitec, TDD No. 97-02-0027. 24 June.

[20] USFWS (United States Fish and Wildlife Service).Inventory Map, Essex Junction, Vermont.

[21] USFWS (United States Fish and Wildlife Service).Inventory Map, Burlington, Vermont.

[22] USFWS (United States Fish and Wildlife Service).Inventory Map, Colchester, Vennont.

1997 (Issued). National Wetlands

1997 (Issued). National Wetlands

1997 Gssued). National Wetlands

[23] VT ANR (Vermont Agency of Namral Resources). 1989 (Issued). Potential Hazardous Waste Site Preliminary Assessment. Ailing Industrial Park, Williston, Vermont. 23 February.

[24] Binkerd Environmental. 1996. Investigation, Ailing Indusfrial Park, Williston, Vermont, April to September. October.

[25] Klein, Andrew (START). 1997. Record of Telephone Conversation with Mr. Greg Bostock (VT DEC), RE: Nearest Private Well to the Mitec Property, TDD No. 97-02-0027. 17 September.

[26] Klein, Andrew (START). 1997. Record of Telephone Conversation with Mr. Neil Boyden (Williston, VT Water Department), RE: Nearest Private Well to the Mitec Property, TDD No. 97-02-0027. 17 September.

[27] United States Census Bureau. 1990. Census Database C90STF1A. Prmtout Dated 31 October 1997.

C:\START\MITEC\MITECFNL.WPD 9 September 1998

MITEC REFERENCES (Concluded)

[28] START (Superfund Technical Assessment and Response Team). 1998. Tier II Data Validation, Organic Analytical Data. Mitec. TDD No. 98-05-0136. 4 May.

[29] START (Superfund Technical Assessment and Response Team). 1998. Tier II Data Validation, Organic Analytical Data. Mitec. TDD No. 98-05-0136. 5 May.

[30] START (Superfund Technical Assessment and Response Team). 1998. Tier II Data Validation, Inorganic Analytical Data. Mitec, TDD No. 98-05-0136. 15 June.

[31] EPA (United States Envfronmental Protection Agency). 1995. Resource Information and Recovery Information System (RCRIS) Data Base. Printout dated 7 July.

[32] Klein, Andrew (START). 1997. Record of Telephone Conversation with Mr. Michael Smith (VT ANR), RE: Mitec, TDD No. 97-02-0027. 11 April.

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