Underground Storage Tanks (UST)

Geophysical techniques can provide a rapid and cost effective solution for site clearance of unknown, lost, or simply forgotten underground storage tanks (USTs).  USTs can come in a variety of types (steel, concrete, and plastic), sizes (75 to over 30,000 gallons), and settings (beneath concrete pads, reinforced floors, asphalt, gravel, partially covered by new construction, etc).  They can be buried to a variety of depths (from a few to tens of feet), typically with little or no evidence of their presence visible at the present-day surface. These USTs can contain a range of products, from petroleum to hazardous waste, and may have leaked or be leaking.

Example underground storage tank successfully excavated after delineation using geophysical techniques.

HGI has over 18 years of experience of locating and identifying USTs at numerous sites across the country. We employ a range of geophysical techniques, including ground penetrating radar, electromagnetic induction, and magnetics, to custom design surveys based on available information on tank design and site conditions.  Survey design can range from simple determination of the number and location of USTs, to accurate delineation of UST footprints and depths to allow tank removal with minimal disturbance to the surroundings or assist with positioning for direct sampling for leak detection.

Three underground storage tanks detected using ground penetrating radar at the site of a former gas station.

An underground storage tank detected using EMI at the site of a former gas station.

Data can be rapidly collected and evaluated and any potential USTs can be outlined on the ground surface at the site during the mobilization.