| WAUSAU GROUNDWATER CONTAMINATION | EPA REGION 5 Marathon County Wausau |
| EPA ID# WID980993521 | Other Names:
Wausau Water Supply |
| Last Update: January 2004 | 7th Congressional District |
Site DescriptionThe Wausau Groundwater site encompasses an area in the northern section of the city of Wausau, Wisconsin, in which the groundwater potentially impacts six of the City Well Field's production wells. the city of Wausau provides drinking water for approximately 35,000 people from groundwater wells, located on both sides of the Wisconsin River. In 1982, three of the wells were found to be contaminated with high levels of volatile organic compounds (VOCs). In 1984, an interim carbon filter system was installed on one of the affected wells until two air strippers could be constructed. The air strippers, installed at the municipal water facility later in 1984, replaced the carbon filters as a long-term solution for providing acceptable drinking water to city residents. Approximately 32,000 people live within a three-mile radius of the site. The Wisconsin River, which bisects the area, is used for commercial and recreational purposes. There are two source areas that are associated with the groundwater contamination at the Wausau site. The first source is an old municipal landfill, located south of City Well Six on the Marathon Electric property along the west bank of the Wisconsin River. The second source is in the Wausau Chemical facility property, located southwest of City Well Three along the east bank of the river. Soils at both source areas are contaminated with VOCs. The soils in the old municipal landfill are contaminated primarily with trichloroethlyene (TCE), and soils on the Wausau Chemical property are contaminated primarily with tetrachloroethelyene (PCE), TCE, and other VOCs. |
| Site Responsibility: | This site is being addressed through federal, state, and potentially responsible parties' actions. |
| NPL Listing History: | Proposed Date: 04/10/85 Final Date: 06/10/86 |
Threats and ContaminantsThe groundwater and soil are contaminated with various VOCs. Potential health risks include accidentally ingesting or coming into direct contact with contaminated groundwater, soil, or soil vapors. |
Cleanup ProgressAn interim record of decision (ROD) to address the groundwater contamination at the site was signed in December 1988, and a consent decree (CD) was entered in federal court during September 1989. The interim remedy included the installation of an extraction well, located in the southern portion of the west contaminant plume, and a pump and treatment system for discharge into the Wisconsin River. The construction for the interim groundwater treatment system was completed by the potentially responsible parties (PRPs) in October 1990. A comprehensive final ROD was signed in September 1989, and a comprehensive consent decree (CD) was entered in federal court during January 1991. The major additional remedy component of the second CD and second ROD was the construction and operation of soil vapor extraction (SVE) systems at each of the two source areas. Construction was completed by the PRPs, and operation began on the soil vapor extraction systems in January 1994. SVE remediation was completed at the source area on the west bank of the Wisconsin River with the system being shut down in April 1996. The SVE system at the source area on the east bank of the Wisconsin River continues to operate, as does the groundwater pump and treatment remedy. A revised groundwater monitoring program was approved in June 2000. A five-year review was completed in July 2000 and found that the remedy remains protective of human health and the environment. |