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.
In 1999, 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.
During the week of September 24, 2007, DENR Division of Waste Management re-sampled the historically contaminated springs east and the stream along Mills Gap road west of the site. In general, the values were consistent with historic data. Spring #2 (culverted) measured 19,700 parts per billion (ppb) TCE and spring #3 (culverted) measured 11,600 ppb. A small unnamed stream originates at the spring, and TCE values at the formation of the stream were 4,670 ppb. A stream flowing west plant parallel to Mills Gap Road measured 247 ppb and dissipated to 12.1 ppb 220 feet further downstream.
The Soil Vapor Extraction system has been operating since July 2007. As of mid-October 2007, 2,151 lbs of volative organic chemicals (vocs), primarily TCE, has been removed from the vadose zone. While the reduction in mass loading is occurring, no immediate reduction in surface water contamination in the spring has been observed to date based on this latest round of sampling. It is plausible that TCE contaminated water travels along the saprolite (weathered bedrock in the saturated zone) to the springs.
The time-critical removal is limited to the vadose zone, and the SVE system has limited impact on the saturated (groundwater bearing) zone. Under these circumstances, reduction of TCE values at the springs is unlikely in the short term. For this reason, limiting access to the contaminated springs is appropriate. The OSC required the PRPs to fence the springs and post warning signs, consistent with the National Contingency Plan, codified in 40 C. F. R. Part 300.415(e)(1). Construction on the fence commenced in November 2007 and was completed in January 2008. Approximately 1,100 feet of fencing was used to surround the springs. The signage posted on the fence reads:
WARNING
This water may be unsafe
AVOID CONTACT. DO NOT DRINK THE WATER
For Details Call: 1-404-562-8767
CTS Corporation had already purchased an easement from the property owner, permitting such an action. The fencing is a part of the Statement of Work in the 2004 Administrative Order on Consent (AOC).
In accordance with the AOC Statement of Work, the Respondents have prepared an evaluation of technologies to mitigate contamination at the springs. The OSC and ERT are currently reviewing the technology evaluation, “
In December 2007, EPA’s Environmental Response Team (ERT) conducted a vapor intrusion study to evaluate vapor phase exposure to TCE in homes near the site. Analytic results will be addressed in a separate report.
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