The Site is located off Mills Gap Road, approximately 1 mile east of Skyland, Buncombe County, North Carolina and consists of approximately 9 acres of maintained grounds containing a large single-story building. In 1952, IRC, Inc. (IRC) bought the land for the Site and constructed the building which it then used for its electroplating operations. In 1959, IRC sold the Site to CTS, Inc. From 1959 until 1986, CTS operated an electroplating facility at the Site. The chemical compound trichloroethylene (a.k.a. trichloroethene or "TCE") was employed by IRC and CTS to clean and/or degrease metal objects prior to electroplating. In 1987, Mills Gap Road Associates (MGRA) purchased the Site and is the current owner.
The Site was identified during follow-up on a citizen complaint in July 1999, to the North Carolina Department of Environment and Natural Resources (NCDENR). High concentrations of chlorinated solvents were identified in two springs and one domestic well, located topographically down-gradient from the site. In August 1999, the NCDENR referred the Site to the U.S. EPA's Emergency Response and Removal Branch (ERRB) for removal eligibility consideration .
On August 20, 1999, the ERRB conducted a removal site evaluation in accordance with the National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 40 CFR §300.410 (Ref. 2). Conditions at the site, specifically contamination of potable drinking water supplies with chlorinated solvents, were found to pose a threat to public health or welfare or the environment. Consequently, bottled water was provided to the four households that had used the contaminated sources for potable water. Subsequently the affected residences were connected to the Asheville-Buncombe municipal water supply.
Analytical results derived from the samples collected from beneath the former CTS plant revealed elevated concentrations of VOCs (e.g. 830,000 ppb TCE), base neutral and acid extractable compounds (BNAs), and petroleum hydrocarbons, most likely #2 fuel oil. TCE was detected in all samples and was typically present at the highest concentrations relative to other chemical compounds identified. Sampling by EPA has indicated TCE, 1,1 TCA, and petroleum contamination in surface water emanating from the site.
Following mitigation of the immediate threat posed by the contaminated springs and waterwell, EPA entered into negotiations with the identified Potentially Responsible Parties and executed an Administrative Order on Consent (AOC) with CTS Corporation and Mills Gap Road Associates in January 2004. On-Site removal activities began in June 2004. Operation of a Soil Vapor Extraction system commenced in July 2007 and is currently on line.
From November 27, 2007 to December 7, 2008, North Carolina Department of Environment and Natural Resources (NCDENR), Division of Waste Management, through a cooperative agreement with U.S. Environmental Protection Agency, sampled 66 residential wells within a one-mile radius of the former CTS Corporation plant on Mills Gap Road (a map of sampling locations can be found in the documents section). Some of the wells served multiple households. The site, currently owned by Mills Gap Road Associates, is an EPA Time Critical Removal.
Of the 66 wells sampled, one active well showed the presence of Trichloroethylene (TCE) in excess of EPA Maximum Contaminant Limits (MCLs). The well located approximately ¾ of a mile northeast of the site, and TCE was measured at 57 micrograms/liter (parts per billion). The MCL is 5 micrograms/liter for TCE. The sampling also detected trace quantities (10.2 micrograms/liter) of cis 1,2-Dichlorethylene, a breakdown product of TCE.
The EPA OSC used his delegated warrant authority to provide bottled water to the affected residence. This substantial threat was documented in an Action Memorandum. EPA re-tested the well in question. The second set of sampling confirmed the presence of TCE at the level indicated by the original testing.
Three separate residential wells had very low levels of chloroform detected in them. One residential well had a trace amount of chloromethane detected in it. The analysis for one residential well detected toluene. All of these detections are below Federal Maximum Contaminant Levels (MCLs).
NCDENR identified all active residential wells in the immediate area of the contaminated well. On January 8, 2008, NCDENR tested eight wells which had not been tested in the November-December sampling event. Of these six additional wells tested, one well, located immediately east of the contaminated well, also contained TCE, though in a quantity below the MCL. No contaminants were detected in the other seven wells.
One well taken out of service in 1999 was resampled as a basis for comparison to historical data. Testing re-confirmed the presence of TCE in that well.
EPA will continue to work with the affected resident to ensure a safe drinking water supply. NCDENR will conduct additional soil sampling near the contaminated well to ascertain if there is a localized contamination source.
EPA has commenced a vapor intrusion study, a soil gas survey, soil sampling through borings. NCDENR has taken surficial soil samples and surface water samples. These studies will be documented in separate Polreps and/or START letter reports.
EPA will coordinate with the Buncombe County Health Center, who will act as a liaison to the municipal water authority. The feasiblility of connection to public water supply for the resident with contaminated water will be evaluated.
Fractures that carry groundwater tend to flow parallel to stream valleys in this section of North Carolina. The geology may not immediately suggest that contamination would extend from the CTS site across the general direction of flow previously observed in residential wells. However, the newly discovered contamination occurs in a deep well, and current groundwater characterization is not sufficient to draw conclusions about source.
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