The site is located at North 102 Front Street in Unity, Marathon County, Wisconsin. (Appendix A, Figure 1). Geographic coordinates of the approximate center of the site are 44°51’05.07” North latitude and 90°19’00.22” West longitude. The site is within a mixed commercial and rural residential area, and is bordered to the West by Highway 13/North Front Street, north by a residence and the former Reigel’s Bar, east by residential properties, and south by County Road K/East Clark Street (Appendix A, Figures 1 and 2). Commercial properties across the public right-of-ways include a railroad property and the Village Hall and associated parking lot on the west side of N. Front Street, and the Unity Post Office south of E. Clark Street. The nearest residences immediately border the property boundary to the north and east.
The site was formerly used as a dry-cleaning facility until the 1970s, after which it has been operated as a gasoline station. The site is listed on the DNR Bureau of Remediation and Redevelopment Tracking System (BRRTS) as Environmental Repair (ERP) Site #23-70-00290 (open since 1991), Leaking Underground Storage Tank (LUST) Site #03-37-218804 and Petroleum Cleanup Fund (PECFA) site #54488-999-02 (1999-2011). Contamination was reported in 1991, and a Phase I Site Assessment report was submitted in 1995. Monitoring wells were installed throughout the site and to the West, across N. Front Street. Primary contaminant constituents include tetrachloroethylene (PCE), trichloroethylene (TCE), and vinyl chloride (VC) in soil and groundwater beneath the site, co-contamination with petroleum constituents included benzene, toluene, ethylbenzene, xylenes (BTEX) and methyltert-butyl-ether (MtBE). Soil and groundwater remediation was conducted on the site from the 1990s through early 2000. Water supply well abandonment and replacement was required in 2011 due to contamination detected in potable wells. Approximately $77,000.00 in PECFA funds were awarded to the Unity Auto Stop for investigation and remedial action associated with petroleum contamination through 2011.
Enforcement action was initiated in 2011, and a Notice of Non-compliance and Notice of Violation was recorded in 2013.
Potable water well sampling indicated contaminant levels exceeded water quality standards in August 2014. Wisconsin DNR has provide bottled water to affected residents and a shower trailer was mobilized and hooked up near the Village hall to provide a shower source for residents that had private wells that were above the dermal contact threat for the chlorinated solvents.
In the fall of 2014, WDNR installed carbon units at the homes and place of business that had chlorinated solvent levels above the dermal contact threat. The homes that did not have carbon units installed are still being provided bottled water by the WDNR.
USEPA Superfund removal branch was requested by the WDNR in September of 2014 to assist on the Unity ground water contamination. U.S. EPA has attended the public meeting in October of 2014 and obtained access to conduct a site investigation at the Unity auto mart in the street right of way and in the empty lot on front street. The data from the site investigation and final report are being finalized and will be posted to the site in late January of 2015.
U.S. EPA plans to conduct additional ground water monitoring, down hole geopyshical work and electro magnatometer surveys in the Spring of 2015. Options are being prepared and cost estimates are being obtained to contain and remove the chlorinated solvents found at the Unity Auto mart. Options and cost estimates are being prepared to provide an alternate water supply for the affected residents in the Village of Unity.
