Orange Cnty. Water Dist. v. Sabic Innovative Plastics United States, LLC

*354 The Orange County Water District (District) was created by the California Legislature to protect and manage groundwater supplies within its territory, which covers most of Orange County, California. The District and other regulatory agencies have long been aware of localized groundwater contamination caused by hazardous substance releases at various sites in the *355 so-called "South Basin" area of Orange County. The hazardous substances in question include various volatile organic compounds (VOC's) and percholorate. A number of these sites have been the subject of government investigations and remediation efforts over the past three decades.

In 1998, two VOC's, tetrachloroethylene (also known as perchloroethylene or PCE) and trichloroethylene (TCE), were detected in groundwater drawn from a drinking water well in the South Basin area operated by the Irvine Ranch Water District (IRWD). Three years later, perchlorate was also detected in the well. The District believed these detections reflected more extensive groundwater contamination than it had previously been aware of. The District undertook efforts to identify the source of groundwater contamination and engaged…