On June 13, 2017 EPA issued a CERCLA 106 Unilateral Administrative Order (UAO) to Stabilus, Inc., ZF Sachs Automotive of America, Inc., Constantia Colmar, Inc., County Line Land Limited Partnership, and Honeywell International, Inc., to conduct the first phase of the bedrock aquifer remedial investigation (Phase 1 Partial RI/FS) at Operable Unit 2 (OU2) of the North Penn Area 5 Superfund Site located in Montgomery and Bucks Counties, Pennsylvania (Site). EPA has determined that the actual or threatened release of hazardous substances may pose an imminent and substantial endangerment to public health or welfare or the environment. Trichloroethylene (TCE) and the other volatile organic compounds detected at the Site, are hazardous substances within the meaning of Section 101(14) of CERCLA. TCE concentrations were found as high as approximately 180,000 g/l in the overburden groundwater adjacent to the building at OU2 of the Site in the area of the storage tank. In addition, TCE concentrations were found as high as approximately 36,000 g/l in the groundwater in the bedrock beneath OU2.