CTS Corp. v. Environmental Protection Agency

A subsidiary of CTS Corp. (plaintiff) owned a property where, from 1959 through 1986, an electroplating process used a hazardous chemical, trichloroethylene (TCE), as a cleaning agent. For over two decades, TCE was released through drains in the plant facility, disposed of through city sewers, and sometimes stored on site. In 1986, plant operations ceased, and in 1987, CTS sold the property. Beginning in the late 1980s and early 1990s, environmental agencies tested the soil around the former manufacturing plant and detected significantly elevated TCE levels. Around 1999, TCE was detected in springs and wells near the former CTS property, while TCE was detected at very high levels in the property’s soil and groundwater. In 2008, 15 wells were tested for TCE in a residential area about a half-mile northeast of the CTS property known as the Oaks Subdivision, and water from four wells was found to be contaminated. Various investigations ensued. In 2010, Lockheed Martin performed an investigation on behalf of the Environmental Protection Agency (EPA) (defendant) and concluded that the elevated TCE levels in the wells were probably caused by other local sources but that leaking septic tanks were probably not the source. The EPA tested the groundwater around the wells for possible links to septic tanks and performed follow-up actions. The EPA ultimately assigned a hazard-ranking-system score of 48.64 to the CTS property and surrounding groundwater (the site), based in large part on the EPA’s determination that TCE from the CTS property had been released to the Oaks Subdivision well water. The site’s score warranted the site’s inclusion on the national priorities list. CTS petitioned for review of the EPA’s decision, arguing that the EPA should have more conclusively ruled out alternative sources, such as area septic tanks, as the cause of TCE contamination at the wells.