POWER remains committed to achieving a full-scale cleanup of the CTS Site.
Clearly, the interim remedial actions are having a positive impact. The Electric Resistance Heating method has proven very successful. Currently we are in the midst of the ISCO remedy. Some concerns remain, such as how bedrock contamination will be addressed. POWER will continue to advocate for ongoing monitoring and action for the health and safety of all area residents.
To view the full June 2020 report from the community’s technical adviser click here.
To see the previous report from March 2020 click here.
From the EPA report: Field work for the second phase of interim cleanup at the CTS of Asheville Site at 235 Mills Gap Road was completed during the first week of March 2020. This phase of the cleanup used In-Situ Chemical Oxidation (ISCO) to treat contamination in a 1.9-acre area. The area treated by ISCO is north of the area that was successfully treated by Electrical Resistance Heating (ERH) in 2018. The EPA expanded the interim cleanup to include this second phase in response to public input.
The ISCO treatment involved injection of potassium permanganate into the ground to oxidize and break down trichloroethylene (TCE) into harmless byproducts like carbon dioxide and water. A total of 76 injection wells were installed between October and December 2019. The injection wells were installed to the top of bedrock, which ranged from 55 to 90 feet below ground surface. From December 2019 through March 2020, approximately 350,000 pounds of potassium permanganate were injected into the subsurface via 380 vertical intervals at the 76 injection wells.
The injected potassium permanganate is expected to take three to five years to reduce TCE in groundwater by 95% to meet the Remedial Action Objective (RAO). Groundwater monitoring will be conducted every six months in the treatment area until the RAO is achieved. If a 95% TCE reduction is not achieved, additional ISCO treatment might be necessary.
The ERH and ISCO cleanup strategies at the CTS of Asheville Site were required under a March 7, 2017 settlement between EPA, the U.S. Department of Justice, CTS Corporation, Mills Gap Road Associates and Northrop Grumman Systems Corporation. To date, the companies have spent $5 million on the ERH component, and $4 million on the ISCO treatment.
During the last week of May the Electric Resistance Heating (ERH) system was powered up to 50% (300 Volts per each electrode) and experienced no issues. The vapor recovery wells and thermal oxidizer were fired-up the beginning of June. Heating and recovery is now underway and working well.
Modems convey information from air monitors to a cloud-based data site. In June a couple of those monitors encountered a manufacturer glitch. Readings were taken by hand and the data was uploaded. There were no equipment failures involving extraction of the contaminant.
More information about the above mentioned event, details on progression of cleanup at the CTS site, and general information on the site can be viewed on EPA’s CTS website here.
You can view the most recent report and photographs from the community’s independent technical adviser here.