POLREP#29 - SPECIAL BULLETIN B Valmont TCE Site (restart) Deer Run Road ...

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POLREP#29 - SPECIAL BULLETIN B

Valmont TCE Site (restart)

Deer Run Road

West Hazleton, PA 18202

Latitude: 040 58'05.41 "N

Longitude: 076 00' 57.01" W (center of chromatex building)

DATE:

March 8, 2007

FROM:

Marjorie Easton, On-Scene Coordinator

Western Response Branch (3HS32)

TO:

Regional Response Center, U. S. EPA Region III

SUBJECT:

Notification of $250,000 Emergency CERCLA Removal Action at the Valmont

TCE Site, West Hazleton, PA

ATTN:

James J. Burke, Director

Hazardous Site Cleanup Division (3HSOO)

Dennis Carney, Associate Director

Office of Preparedness and Response (3HS30)

Fran Burns, Chief

Western Response Branch (3HS32)

I.

Issue

This document is for the installation of indoor air systems at several homes to remove an

immediate threat of exposure to residents due to the Valmont Site. An engineering

evaluation/cost analysis (EE/CA) dated December 2006 was prepared for the Valmont

Trichloroethene (a.k.a. trichloroethylene, TCE) Site located in West Hazelton, Hazle

Township, Luzerne County, Pennsylvania. EPA Region III evaluated whether a removal

action would be appropriate for addressing current and future indoor air contamination

that is attributable to the Site. The purpose of the EE/CA was to analyze various

alternatives that would satisfy the objectives for indoor air contamination and

recommend a removal action that would best address the problem. The December 2006

EE/CA concluded that subslab depressurization systems would be protective of human

health and recommended that they be installed in nine of the 27 homes investigated. The

homes to be addressed do not currently have subslab depressurization systems and they

are located above or within the path of VOC groundwater contamination that is believed

to be attributable to the Chromatex facility. Residential subslab VOC vapor samples

collected during 2006 indicated that TCE was present beneath the homes at levels that

posed an unacceptable health risk to residents due to the potential to migrate and impact

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indoor air quality. During previous Site actions, subslab depressurization units were

installed by EPA in eight homes within the neighborhood that were also located in the

path of contamination. In addition, EPA covered the basement sumps in three additional

homes to mitigate vapor intrusion of site-related VOCs.

The release meets the criteria for conducting a removal action under Section 300.415 of

the NCP. The OSC has determined that immediate funds are needed to mitigate the

threat posed to human health and the environment. The OSC has authorized a budget for

the removal action not to exceed $250,000, in accordance with EPA redelegation of

authority 14-2. This Special Bulletin documents the scope of work needed to complete

the removal action to protect public health and the environment.

II.

Background

A.

Site Description

The Valmont TCE Site is currently a National Priorities List ("NPL") Site. The Site

consists of one known source, the Chromatex Plant No. 2 (a.k.a. Chromatex) and

contaminated groundwater believed to be attributable to the Chromatex facility.

Chromatex is located at the edge of a large industrial park at 423 Jaycee Drive, West

Hazleton, PA. The facility was a former upholstery manufacturing plant that, among

other activities, used TCE in applying stain guard treatments to fabrics. Investigations

have found TCE contamination in Site soils and TCE and 1,1,1-trichloroethane (1,1,1TCA) in groundwater beneath the Site. The groundwater plume associated with the Site

has migrated approximately 1,200 feet beneath a residential neighborhood that borders

the northeast side of the property. The total number of homes in the residential area is

59, and there are five apartment complexes with approximately 50 apartments. The VOC

plume also extends approximately 700 feet southwestward from the facility because of a

local groundwater divide that splits the flow direction beneath the facility into northeast

and southwest components. The depth of VOC contamination beneath the facility may

be 300 feet or more. This Special Bulletin addresses the concerns of indoor air

contamination identified in the December 2006 EE/CA.

EPA investigated many of the homes in the neighborhood to determine if the

contaminated groundwater could be causing indoor air contamination. The results

suggested that indoor air could potentially be impacted above acceptable health risks by

chlorinated ethanes and ethenes, primarily TCE, which are the primary chemicals found

in the groundwater VOC plume. Other VOCs were also detected at lower concentrations

in the indoor air, however TCE was the primary risk driver.

EPA has determined that nine residential homes have elevated subslab VOC

concentrations that pose unacceptable risks to human health due to the potential for

migration of the VOCs into indoor air. These homes are located within the path of

groundwater contamination believed to be attributable to Chromatex. The December

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2006 EE/CA has determined that installation of subslab depressurization systems in these

homes would be protective of human health during both present and future use of the

homes. There is potential that the number of homes affected by VOC vapors may

increase due to changing conditions at the Site, or as new information becomes available.

B.

Site Background

EPA initially responded to the Site in 1987 when VOC contamination was found in the private wells of residents located in the neighborhood northeast of Chromatex. Under an

EPA removal action, bottled water and carbon filters were provided to the affected

homes. Later, public water supply lines were extended into the neighborhood to supply

clean drinking water to the residents. Between 2001 and 2003, EPA conducted an

investigation that included multimedia sampling efforts and determined that the air in

several homes was potentially being affected by VOCs emanating from contaminated

groundwater. Indoor air sampling results indicated that TCE was detected in the air

samples from six houses and 1,1,1-TCA was present in 14 houses. As a result of the

elevated levels, eight of these houses were equipped with air filtration systems under a

removal action conducted between 2003 and 2004. In August 2004, EPA completed a

soil removal action at the Site where more than 18,000 tons of contaminated soil was

excavated and taken off-site for disposal. That same year, EPA began conducting pilot

and treatability studies on soils and groundwater beneath the former Chromatex building.

A remedial investigation report was completed by the end of 2004. During 2006, EPA

removed the temporary air filtration systems from the homes and replaced them with

more cost-effective and permanent subslab depressurization units. In addition,

construction began on a soil vapor extraction (SVE) system to strip VOCs from soils

located beneath the former Chromatex building while review continues for chemical

oxidation technology and pump and treat for groundwater treatment. The SVE system

began operation on March 1, 2007.

During March and April 2006, EPA performed additional Site characterization activities

in the residential neighborhood located adjacent to the former Chromatex facility. The

work was conducted in support of an EE/C A for contaminated indoor air (OU4). The

purpose was to identify potential and current exposures associated with soil vapor

intrusion and to characterize the nature and extent of VOC subsurface vapor

contamination. Sampling access letters were sent to all residents that were thought to

overlie the groundwater contamination plume and did not have depressurization systems.

Vapor samples were collected from beneath 27 homes that provided access and analyzed

for VOCs. Data from the subslab investigation was used to assess human health risks

associated with vapor intrusion into the homes. The December 2006 EE/CA report for

indoor air considered information from the 2004 remedial investigation report. Based on

the 2006 subslab data and associated human health risk assessment, a risk greater than

10"4 and in some cases 10"2 exists at nine homes from actual or potential indoor air

contamination believed to be attributed to groundwater contamination. Construction of

subslab depressurization systems was recommended as the best alternative for mitigating

indoor vapors.

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The Valmont TCE Site has a long and varied history of environmental activity that may

be found in other Site related documents including previous Action Memorandums, the

2004 Remedial Investigation Report, and the groundwater EE/CA.

C.

Types of Substances Present

The primary VOCs found in contaminated groundwater beneath the Chromatex facility

and the residential neighborhood include TCE (up to 17,000 micrograms per liter (ug/L)),

1,1,1-TCA (up to 560 ug/L) and cis-l,2-DCE (up to 150 ug/L). Vinyl chloride, iron,

manganese, and chromium are also chemicals of concern (COCs). 1,1,1 -TCA and

tetrachloroethene (PCE) were detected in groundwater samples at the Site, but they were

not detected in soil samples from Chromatex. The PCE contamination may be due to

another source area that is being investigated by PADEP.

According to the 2004 Remedial Investigation Report, samples collected from indoor air

in 10 of 42 homes located north of Chromatex were found to contain TCE (0.24 to 16.4

micrograms per cubic meter (ug/m3)). Detections of 1,1,1-TCA (0.25 to 1,500 ug/m3)

were found in 17 homes. 1,1-dichloroethene (1,1-DCE) and 1,3-butadiene were also

detected at lower concentrations.

More than half of the subslab VOC vapor samples collected beneath residential homes

during 2006 contained detections of 1,1,1-TCA (up to 3,000 ug/m3) and TCE (up to

55,000 ug/m3). In 20 percent of the samples 1,3-butadiene (0.28 to 2 ug/m3) was

detected. Toluene (1 to 53 ug/m3) was detected at every residence. In less than 10

percent of the samples, low concentrations of 1,1-DCE, cis-l,2-DCE, trans-1,2-DCE, 1,2dichloroethane (1,2-DCA), and carbon tetrachloride were detected. PCE, ethylbenzene,

and xylene, were also detected in one home. .Chloroform was detected at one home.

TCE was the most significant risk driver in each affected home and in many cases the

only risk driver. Chloroform was considered the only other major contributor to

substantially influence unacceptable cancer risk in the one home where it was found.

D.

National Priorities List (NPL) Status

The Site was listed on the NPL on September 13, 2001. A full-scale remedial

investigation/feasibility study (RI/FS) of the Site began in January 2002 and a draft

report was submitted to EPA for review. Construction of a Soil Vapor Extraction/Air

Injection (SVE/AI) system to address contaminated subsurface soils beneath the former

Chromatex building foundation began in November 2006. The SVE system began

operation on March 1, 2007. A public meeting was held on January 25, 2007 to discuss

.proposed options for addressing groundwater contamination at the Site. EPA's preferred

option is a pump and treat system enhanced by in-situ chemical oxidation. After a 30day public comment period, EPA will issue an Action memorandum with its preferred

option for addressing contaminated groundwater.

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E.

State and Local Authorities Roles

The Pennsylvania Department of the Environment (PADEP), Northeast Region,

requested EPA assistance with assessing the site in question. EPA continues to

coordinate efforts with PADEP, and other Federal, State and local authorities regarding

developments at the Site. PADEP is performing additional investigations to determine if

other sources may be contributing to groundwater contamination at the Site.

HI.

Threats to Public Health or Welfare or the Environment

Section 300.415 of the NCP, 40 C.F.R. ¡ì 300.415, lists factors to be considered in

determining the appropriateness of a Removal Action. Paragraphs (b)(2)(i) and (vii) of

Section 300.415 directly apply as follows to the conditions at the Site.

Section 300.415 (b)(2)(i)

"actual or potential exposure to nearby human

populations, animals, or the food chain from

hazardous substances or pollutants or

contaminants."

The Site is listed on the NPL as "contaminated ground water in the ... residential

neighborhood." The NPL further specifies that "contamination is caused by high

concentrations of trichloroethylene (TCE) and lower concentrations of other...

(VOCs)." During the remedial investigation, EPA determined that the most

prevalent VOCs detected in soils at the Chromatex property are TCE, cis- and

trans-1,2-DCE, and 1,1- dichloroethane (DCA). TCE was found in a well at the

Plant at up to 17,000 ^g/L and in residential wells up to 1,630 ng/L. 1,1,1Trichloroethane (1,1,1 -TCA) was found in a well at the Plant, also. The same

substances have been detected in indoor air samples collected from the residential

area.

There is a potential for VOCs to migrate from groundwater into indoor air at the

Site. Trichloroethene and 1,1,1-TCA are VOCs which means that they are readily

transferable from water to air, making them a threat from inhalation if found in an

exposure pathway to humans at levels of concern. More recent investigation of ?

the homes located in the path of the groundwater plume indicated that VOC

vapors containing chlorinated ethanes and ethenes, primarily TCE, were detected

at unacceptable human health risk levels beneath nine of the homes. These homes

are not currently equipped with contaminated air mitigation systems.

Risks varied for each home based upon which contaminants were present. The

risks and potential risks associated with vapor intrusion involve cancer risks

above 10^ and Hazard Indices above 1. The site-related chemicals associated

with these risks are TCE; the associated and breakdown products of TCE

(chlorinated ethenes and ethanes) are also of potential concern. Therefore, EPA's

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