Past Work on Site

​: Inside Building 300 was a concrete sump with a dirt floor, essentially a dry well, which was used to dispose of various products. A sample collected in 1992 and documented in the Environmental Compliance and Investigation Report, dated 1992, showed elevated levels of total petroleum 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 (less than one drum) 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. As the contamination is not currently accessible to any potential receptors, the department determines that no further remedial action is planned for the Building 300 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 Alaska Administrative Code (AAC) 75.325(i).