Retail Fuel Service Station

In support of regulatory closure at an operating Salem, Oregon retail fuel service station, Farallon provided technical services that included completion of a subsurface investigation to address data gaps in previous subsurface work conducted by others.  A subsurface investigation was conducted to delineate the nature and extent of TPH and associated contaminants in soil and groundwater attributable to releases from former ASTs, fuel dispenser islands, and routine service station operations.  The information obtained from the subsurface investigation was used to prepare a conceptual site model, and to conduct a risk-based evaluation of contaminants, potential receptors, and exposure pathways at the site in accordance with the Oregon Department of Environmental Quality (DEQ) program for Risk Based Decision Making for the Remediation of Petroleum Contaminated Sites using DEQ’s generic remedy cleanup levels.  Corrective actions included decommissioning an irrigation water-supply well to eliminate potential exposure to groundwater, and installing an oil-water separator on the site’s stormwater conveyance system up-gradient of a trench drain discharge point to eliminate contaminants in surface water and a source of contaminants to surface soil.  As a result of the risk-based evaluation and the corrective actions taken, DEQ issued a No Further Action determination for the site.