Past Work on Site

Inside Building 601 was a concrete sump with a concrete floor. The sump was plumbed to discharge to the subsurface outside the foundation of the building. A sample collected in 1992 and documented in the Environmental Compliance and Investigation Report, dated 1992, showed elevated levels of total petroleum hydrocarbons, benzene, toluene, xylenes, and polycyclic aromatic hydrocarbons. In the Site Cleanup and Investigation Report, dated 1996, field activities are described concerning the sump including the removal of an unspecified volume of soil and the filling of the sump with concrete. Samples for volatile organic compounds and semi-volatile organic compounds were collected prior to filling with concrete and no elevated level of any analyte was detected. It is unknown if there are elevated concentrations of petroleum hydrocarbons or metals in the soil below the sump, however the sump has been filled with concrete and the area around it is a concrete pad covered with a building which will prevent the infiltration of water from the surface and the migration of contamination. Samples were collected at the outfall and no elevated levels were detected. As the contamination is not currently accessible to any potential receptors, the department determines that no further remedial action is planned for the Building 601 Sump. If, in the future, the concrete floor is removed and the soil below and around the sump is accessible, the area should be characterized and any contamination managed in accordance with department regulations and guidance, as required by 18 AAC 75.325(i).