Comparison of surface and aerial geophysics for characterizing a hazardous waste site: A case study

This paper presents a cast study comparing geophysical data collected from helicopter and at the surface at Solid Waste Area 4 (SWSA 4), a hazardous waste site on the Oak Ridge Reservation near Oak Ridge, TN. The aerial survey of SWSA 4 was part of a larger aerial survey designed to better characterize the numerous waste sites on the 35,252-acre reservation, locate any unrecorded waste areas, and assist hydrogeologists mapping the local hydrogeology. The aerial data were collected from November, 1992 through January, 1993. Analysis of preliminary maps shows that contours of airborne magnetic and electromagnetic data clearly delineate the boundaries of SWSA 4, and highlight anomalous areas within the burial ground (including several that the authors now intend to survey on the ground). The ground based measurements were closer to the buried targets and more tightly spaced, yielding data that better resolve the boundaries of the individual waste trenches. This case study demonstrates that the combination of aerial reconnaissance and follow-up surveys on the ground, so effective in mineral exploration, can be equally effective for characterizing large hazardous waste sites