Cuyama, California: Ex-Situ Treatment of Diesel-Impacted Soil

Ex-situ thermal remediation was used to treat diesel-impacted soil from a former aboveground storage tank spill in Cuyama, Central California. GEO's case study identifies ECC as the consultant.

The ex-situ treatment pile and equipment used for diesel-impacted soil in Cuyama, California.

Approximately 2,877 cubic yards of affected soil were excavated from the vadose zone to a depth of 5 feet and stockpiled on a containment barrier. The source reports a treatment volume of 77,692 cubic feet. Thirty-six Gas Thermal Remediation heater wells were installed in the treatment pile.

Baseline samples recorded a maximum diesel-range total petroleum hydrocarbon concentration of 31,900 mg/kg and an average of 9,645 mg/kg. Heating and liquid-phase recovery continued for 45 days, with an average target treatment temperature of 200°C.

Sixteen post-treatment soil samples confirmed a 99.7% reduction in contaminant concentrations relative to baseline sampling. The case study reports that the project met its remedial goals, received a No Further Action notice for the onsite soils, and was allowed to reuse the treated soil onsite as road base. These outcomes refer to this project and its approved reuse conditions.