SITE INFORMATION AND CORRESPONDENCE

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y the former UST excavation indicated hydrocarbon contamination. 4 Groundwater samples collected on November 6 and 21, 1991 and ry analyzed indicated very low values of Total Petroleum Hydrocarbons } as gasoline (TPHG) and Toluene, Ethylbenzene and Xylene. Na benzene was reported in the groundwater samples. On June 5, 1995, six days after the installation of there monitoring wells on May 30 1995, John N. Alt and John P. Cummings of JPCA went to the site to collect groundwater samples. The wells were developed by pumping, purging and collecting the purged groundwater in 55-gallon drums labeled awaiting analysis. Each of the wells was pumped to dryness three times. The pump was decontaminated using tri-sodium phosphate solution (TSP) and twice rinsed with the last rinse using distilled water prior to being used in each well. Three` groundwater samples coT7eced�from 'the Txnontorrig w 71s`were analyzed for Total Petroleum Hydrocarbons as Gasoline (TPHG) and Benzene, Toluene", Ethylbenzene and Xylene (BTEX) . The results of the analysis, for the June 1995 sampling, in parts per, billion (ppb) are shown in Table 1. TABLE 1 Groundwater sample Analysis Results in ppb. J Sample ID TPHG B T E X MW-1 1, 400 8. 1 1. 6 13 89 Mrn1-2 2 , 100 33 ND ND 44 MW-3 13 , 000 120 22 130 920 ND = Not Detected The concentrations of TPHG and BTEX in the groundwater were high. Further characterization. of the site is required prior to ' any remediation- of the subject parcel. The -workplan f"or four' q`ua`rters -w - =- commencing approximately the first week of June 1995 and ending the 1 first week of March 1995, will include the following items. Costs- will ostswill be submitted on a separate document. On completion of the . N four quarterly monitoring reports, a recommendation for further work will be included in the March 1995 report. SCOPE OF WORK (WORKPLAN) ,1) Notify the San Joaquin County Environmental Health Division (SJCEHD) 48 hours prior to initiation of field work. 2