Using ground penetrating radar and electromagnetic induction methods to detect and delineate underground storage tanks

"Proposed expansion of highways 15, 150, and 291 required several gas stations to be demolished. During demolition of a gas station property, damage can occur to the underground fuel storage tanks and associated utility lines. Noninvasive mapping of these features prior to excavation can greatly reduce problems associated with unexpected tank discovery.In this study, noninvasive geophysical methods were used to map the underground fuel storage tanks and associated utility lines. The application of geophysical tools ensured the detection and delineation of the underground fuel storage tanks using noninvasive, nondestructive, and time efficient methods. A variety of geophysical methods was considered. To accomplish the goals of the project in a time efficient manner without compromising resolution, the electromagnetic induction and ground penetrating radar techniques were chosen. The complementary use of ground penetrating radar and electromagnetic methods increased the likelihood of detecting subsurface anomalies.The locations of the existing tanks and associated utility lines can be interpreted in both ground penetrating radar profiles and contoured electromagnetic induction maps. Electromagnetic induction maps provided an excellent cost effective initial survey for the detection of the underground storage tanks. Ground penetrating radar proved important for the accurate delineation of these tanks. A priori information on expected underground fuel storage tank locations proved incorrect. The integrated use of ground penetrating radar and electromagnetic induction methods allowed us to create a map of exact tank locations at each site in this study. These detailed maps could then be used to guide demolition, eliminating extra hydrocarbon contamination by preventing damage to the tanks during excavation"--Abstract, pages iii-iv.