California Regional Water Quality Control Board, Central Valley Region, 1102 pp, 2018

Mercury Cleaners operated as a dry cleaner from 1947 to 2014. The facility used a variety of dry cleaning solvents, and the site requires soil and groundwater treatment to remediate the impacts of petroleum-based Stoddard Solvent and of PCE and its daughter products. Cleanup began in 2015 with a soil vapor extraction (SVE) system pilot test, which is currently operating. To address soil contaminated with PCE above residential screening levels in an area ~40 ft by 40 ft in plan, a source area removal action was implemented in November 2016 using in situ electrical resistance heating (ERH) thermal desorption. Comprising 15 electrode/vapor recovery wells located within the source area, the ERH system was designed to volatize VOCs in the subsurface for SVE system removal and treatment. The goal of the removal action was to reduce contaminant mass by > 99% and lower concentrations of TPH, PCE, and other VOCs below the soil and groundwater cleanup goals. ERH system operation ended on July 7, 2017. Although source area cleanup goals were not met completely, significant PCE mass was removed from the source area. http://geotracker.waterboards.ca.gov/esi/uploads/geo_report/5028631806/T10000003411.PDF