Using Surface Geophysics To Locate Buried Drums At An Industrialized Superfund Site In New Jersey

Objectives of a surface geophysics investigation at an SO-acre Superfund site in New<br>Jersey were to locate potential source areas of contamination leaking from buried<br>drums and underground tanks. Surface geophysics was chosen as a cost-effective, nonintrusive<br>method to accurately identify potential source areas and reduce risk by<br>locating areas of buried metal to be avoided during a subsequent phase of drilling.<br>Areas of buried metal identified using geophysics were investigated during a later phase<br>of test-pitting to characterize the type of materials buried at the site. A<br>magnetometer/gradiometer was selected as the best method to conduct the study, since<br>the investigation target was buried metal. The vertical gradient often provides higher<br>resolution of magnetic anomalies and may allow the collection of useful data closer to<br>buildings than do total field measurements. The gradiometer was critical to the<br>investigation, since many magnetic interferences such as buildings, overhead process<br>lines, underground utilities, and fences were present at the site. Since the potential<br>target could be as small as a single drum, the survey was performed on a 10 by 10 foot<br>grid spacing.