Farallon Devises Shorter Route to NFA


Owners of a property that had undergone cleanup of gasoline in soil and groundwater called on Farallon for help with regulatory closure.

When another consultant recommended costly subsurface investigations to support a request for regulatory closure, the property owners contacted Farallon for a second opinion.  Farallon’s evaluation indicated that additional investigations were not necessary.  Farallon presented existing information and limited focused sampling results to the Oregon Department of Environmental Quality (DEQ), and successfully secured a No Further Action determination for the property.

Gasoline-contaminated soil and groundwater had resulted from a release from an underground storage tank associated with a historical service station on the property. The release was discovered in the late 1980s during removal of the tank; cleanup actions were completed by the late 1990s.  A two-story building with a basement that included a subslab membrane system to prevent vapor intrusion into the building had been constructed on the property.  The weight of evidence Farallon presented to DEQ confirmed that the prior release of gasoline to soil and groundwater did not pose a risk to the environment or to current or likely future receptor populations for the exposure pathways applicable to the Site.  The Site received a No Further Action determination from DEQ, and the property is available for sale without stigma or restrictions on future use.

“Farallon was able to minimize the need for additional subsurface investigation by reviewing results from previous investigations and preparing a conceptual site model,” said Craig Ware, Farallon Principal-in-Charge of the project.  According to Project Environmental Scientist Jennifer Whaler, “When Farallon identified the need for further groundwater sampling to evaluate groundwater contaminant conditions beneath the building, we were able to collect samples from existing on-site dewatering sumps, eliminating the need for drilling.”