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Catherine Quinn <br /> Page 2 <br /> June 27,2002 <br /> sample from the soil collected in the roll off bins,and the groundwater sample were sent to <br /> Alpha Analytical for analysis. <br /> On November 21,2001,additional impacted soil was excavated,i.e.,over excavated. The <br /> excavation was deepened to approximately 8-feet bgs and expanded an additional 5-feet <br /> laterally. Excavation continued until photo-ionization detector(PID) readings from <br /> excavated soils were less than 0.01 parts per million. Four sidewall samples,collected just <br /> above groundwater from areas suspected to contain petroleum hydrocarbons,and a <br /> composite sample of soil collected in the roll off bins were sent to Alpha Analytical for <br /> analysis. The excavation was backfilled with clean soil removed during excavation. <br /> Soils generated during excavation activities were stored in roll-off bins prior to disposal. A <br /> total to 48.71 tons of petroleum hydrocarbon impacted soil was transported for disposal to <br /> Forward Landfill in Manteca,California. <br /> The soil samples collected on November 19 and 21,2001 were analyzed for total petroleum <br /> hydrocarbon(TPH) as jet fuel,diesel,and gas;and benzene,toluene,ethylbenzene,and <br /> xylenes(BTEX). The groundwater sample collected on November 19,2001 was analyzed for <br /> these same parameters and also for methyl tert-butyl ether(MTBE). The two composite soil <br /> samples from the roll-off bins were analyzed for landfill disposal purposes for TPH as jet <br /> fuel,diesel,and gas;BTEX;and lead. The analytical results for the soil,groundwater,and <br /> composite soil samples are provided in Attachment 1,except for the lead analysis. Lead <br /> was detected at 7.2 and 7 mg/kg for the composite samples collected on November 19 and <br /> 21,respectively. <br /> Objective and Rationale <br /> The objective of the work in this work plan is to assess the lateral extent of hydrocarbon <br /> affected groundwater from the impacted soils that were excavated on November 19,2001 <br /> and over-excavated on November 21,2001. This will be accomplished by collecting shallow <br /> water table groundwater samples and analyzing the samples for hydrocarbon constituents. <br /> Additional soil sampling will not be performed because the excavation and over- <br /> excavations activities removed virtually all detectable hydrocarbons in soil based on the <br /> field PID readings the confirmation sample analytical results. Analysis of lead will not be <br /> performed because,as discussed below,the lead detected for the two composite samples are <br /> representative of background soil conditions and likely not related to conveyance of <br /> petroleum products through the pipeline. The rationale for this work is further described <br /> below. <br /> Soil sampling will not be performed for analysis of TPH and BTEX because confirmation <br /> soil samples indicated that the November 19,2001 excavation and November 21,2001 over- <br /> excavation activities removed all detectable hydrocarbons,except for one small detection of <br />