NPL Site Narrative for Wausau Ground Water Contamination
WAUSAU GROUND WATER CONTAMINATION
Federal Register Notice: June 10, 1986
Conditions at proposal (April 10, 1985): Wausau's water supply system serves 32,000 residents of Wausau, Marathon County, Wisconsin. According to tests conducted by the city in March 1982, three of the city's six wells are contaminated by several volatile organic compounds (VOCs) at levels greater than those recommended for drinking water by EPA and the Wisconsin Department of Natural Resources (WDNR).
In the spring of 1982, the city first detected VOC contamination in City Well #3, east of the Wisconsin River. By the summer of 1982, analyses of water from City Well #6, west of the Wisconsin River, detected appreciable amounts of trichloroethylene (TCE) and trace amounts of perchloroethylene (PCE) and 1,2-transdichloroethylene (DCE). By the fall of 1982, City Well #4, also east of the Wisconsin River, showed contamination by DCE, PCE, TCE, and toluene.
Since these discoveries, the city and WDNR have made considerable efforts to monitor and define the extent of ground water contamination. EPA also conducted a hydrogeologic investigation to determine potential sources and the extent of contamination. Several potential sources were investigated.
The city had been able to supply water by pumping mainly from uncontaminated Wells #7 and #9, with blending from contaminated Wells #3 and #6 to meet demand. However, in the spring of 1984, increasing levels of contamination in these wells led to VOC levels at the tap greater than EPA and WDNR recommendations. Therefore, in the summer of 1984, EPA used CERCLA emergency funds to install carbon filters to remove VOCs. The filters were used until they could be replaced by two air strippers. EPA provided a research grant to install the air stripper at Well #4. The city funded the air stripper at Well #3.
Status (June 10, 1986): EPA is considering various alternatives for the site.
For more information about the hazardous substances identified in this narrative summary, including general information regarding the effects of exposure to these substances on human health, please see the Agency for Toxic Substances and Disease Registry (ATSDR) ToxFAQs. ATSDR ToxFAQs can be found on the Internet at ATSDR - ToxFAQs (http://www.atsdr.cdc.gov/toxfaqs/index.asp) or by telephone at 1-888-42-ATSDR or 1-888-422-8737.