Hazardous Sites and Substances in Minnesota
Background Information - Baytown Township Groundwater Contamination Site
Trichloroethylene (TCE) is one of a class of chemicals called Volatile Organic Compounds (VOCs). VOCs are a large class of chemicals that have been used throughout the United States since the 1940s by industry, commerce, households and the military. Because they were commonly used for residential and industrial purposes, and stay in the environment for a long time, VOCs are a threat to ground water quality.
TCE was first found in the groundwater in the Baytown Township area in 1987. The Baytown Groundwater Contamination Site is listed as a state and federal Superfund site. The Minnesota Pollution Control Agency (MPCA) has been the lead agency, in cooperation with the U.S. Environmental Protection Agency, in investigating and cleaning up the source of the TCE. MPCA also oversees the sampling of private wells in the area and provides treatment systems for private wells that exceed the state’s health based guidance. For more information about MPCA activities, see Baytown Township Groundwater Contamination Site.
MDH is responsible for reviewing private well sample results and issuing drinking water advisories, as needed. MDH also samples public water supply wells in the area. MDH activity at the site increased dramatically in February 2002 when the agency changed its health advice for TCE from 30 micrograms per liter(µg/L)to 5 µg/L, based on new information on its toxicity. It is known that exposures to TCE did occur as a result of the Baytown Ground Water Contamination Site.
In 2004, MDH completed a report on the site, known as a Public Health Assessment that describes activities at the site at that time and MDH's recommendations to protect public health. The MDH concluded that there was no apparent public health hazard because exposure to TCE above the HRL of 5 µg/L was being prevented by use of whole-house GAC filtration units on private wells, and because overall levels of TCE in the Bayport municipal system were below regulatory and health-based standards in place at that time. To view the 2004 public health assessment and recommendations please see the Public Health Assessment for the Baytown Groundwater Contamination Site 2004.
In 2005, MDH’s Well Management program expanded the boundaries of the existing Special Well Construction Area (SWCA). The current boundaries of the SWCA are shown on the map of the site (link). New wells constructed within this area are subject to special restrictions regarding construction and sampling requirements. State law also requires that, during a property sale, the owner must disclose that their property is located within a SWCA. For more information about the SWCA, see the the Baytown Special Well Construction Area Update.