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EEC S146201 UniFirst Stockton September 24.2004 • The source of the oil release was removed 7.0 OIL RELEASE REMEDIATION AND CONFIRMATION SAMPLING This section discusses the removal of the soil affected by the release, confirmation sampling, soil disposal, and water disposal at the subject site Soil remediation and confirmation sampling was conducted under the supervision of the SJCEHD in accordance with its contract with the State Water Resources Control Board (SWRCB)to provide oversight for petroleum UST sites Prior to conducting remedial activity and confirmation sampling, EEC prepared a workplan ' describing the proposed remediation activities and methods A copy of the workplan is included in Appendix J In accordance with Proposition 65 requirements, the SJCEHD circulated a Public Notice to notify the residences in the surrounding neighborhood of the proposed remedial activities, and to solicit comments to the proposed remedial activities The neighborhood ' notification was put into circulation on December 17, 2003 After seven days, no comments were received, therefore, in accordance with proposition 65, SJCEHD approved the workplan A copy of the public notification is included in Appendix J Verbal approval of the workplan was granted ' on December 27,2003 7.1 Soil Excavation On January 16, 2004, remedial activities were conducted to remove hydrocarbon and VOC impacted soil from the site which resulted from the UST release The oil which had leaked from the UST covered an area approximately 50 by 100 feet in the northwest corner of the construction site EEC used visual inspection and PID readings as field indicators to guide the excavation of impacted soils Field screening suggested that the oil release only impacted the upper 1- to 3- inches of soil The impacted soil was scraped from the surface using a backhoe and loader The excavated material was stockpiled on plastic, until it was removed by a licensed waste hauler ' 7 2 Post Oil Release Confirmation Sampling EEC collected confirmation samples at the locations designated on the workplan approved by the SJCEH A total of 17 samples were collected on a grid system The grid layout and sample location map are shown on Figure 6 Samples were collected using a 6-inch stainless steel sampling sleeve, capped, labeled, placed on ice and transported to Cal Tech under proper Chain of Custody documentation Each of the 17 samples collected were analyzed for TPH by EPA ' Method 8015 full range scan and for VOCs by EPA Method 8260 Results of the analysis showed only minor concentrations of TPH diesel range and PCE in the soil (Table 5) Results of post oil release confirmation sampling indicate • TPH gasoline range hydrocarbons were detected ranging from non detect(<a 01)to 2 4 ' ppm TPH diesel range hydrocarbons were detected ranging from non detect(<10)to 110 ppm m PCE was detected ranging from non detect(<0 005)to 0 68 ppm 12