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Based on the previous environmental data generated for the site, soil contamination was P discovered on November 5, 2005 on the southern portion of the block during grading activities for construction of a loading dock and parking area to support the new laundry facility constructed on the northern portion of the block Based on this discovery, a tsurface investigation was undertaken under SJCEHD's oversight including seven surface soil sample locations and a subsurface investigation including nine subsurface sample locations was conducted in order to assess the extent of soil contamination Based on the results of the investigation, contaminated soil was excavated and disposed of at an offsite, ' licensed landfill The results from soil confirmatory samples collected from the excavation area indicate some impacted soil remained in place at the site Contaminants detected in the confirmation samples included total petroleum hydrocarbons (TPH) in the motor oil range (67 parts per million [ppm] maximum), TPH in the gasoline range (100 ppm maximum), ethylbenzene (0 075 ppm maximum), xylenes (42 ppm maximum), and ' tetrachloroethene (PCE) (0 032 ppm maximum) ' In December of 2003, while in the process of grading and excavating for the installation of the loading dock ramp on the southern side of the new laundry facility, UmFirst employees observed a black oily liquid on the surface of rainwater that had accumulated '. in the excavation in the northwest corner of the parking lot area The SJCEHD was notified and in turn the SJCEHD contacted the California Department of Fish and Game ' (CDFG), SJCEHD-Emergency Response, City of Stockton, and U S Environmental Protection Agency (EPA) in order to inform them of the oil release Emergency response action was deemed necessary and with verbal concurrence from SJCEHD and CDFG, ' response actions were undertaken ' The emergency response consisted of removal of the oil/oil-water mixture from the excavation, temporary storage of the removed materials, and placement of engineering controls (berms) to prevent the escape of oil/oil-water mixture from the site into nearby storm drains Approximately 22,000 gallons of oil/oil-water was removed from the site over a six-hour period The liquid was stored in two 20,000-gallon Baker Tanks ' mobilized to the site On December 12, 2003, the source of the release was investigated The results of the investigation revealed the presence of a 2,500-gallon UST located ' approximately four feet below ground surface (bgs) Once exposed, it was evident that fill ports on the UST had been exposed during grading operations When rainwater accumulated in the excavated area, the water infiltrated the UST through the exposed fill ports, displacing the oil and forcing it to the surface of the rainwater accumulated in the • excavation area i i2 V\Goodwin ProctorTinalReport doc