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fr. CRYSTAL CREAMERY STOCKTON WKA No. 1628.10 February 5, 2000 Page 7 sediment. Temperature,pH, and Conductivity readings were additionally recorded during the development; surging and pumping continued until these readings stabilized. On January 23, 2000,we completed quarterly sampling at the site and collected the first water sample from MW8. Based on analysis,the water sample obtained from this boring revealed no detectable concentrations of petroleum hydrocarbons or the common seven fuel oxygenates MTBE, DIPE,ETBE, TAME, Tert-Butanol, Methanol and Ethanol. The only analytes reported in the sample were Ethylbenzene and Xylene at a concentration of 1.9 ug/L each. As required by SJCPHS, we are including the results of our most recent groundwater sampling event as fulfillment of quarterly monitoring requirements. Our most recent groundwater elevation measurements of the eight on, and offsite monitoring wells MW1 through MW8 were obtained on January 23, 2001. Based on this measurement, depth to groundwater ranges between >== 14.59 and 15.20 feet below grade(Table 1). The overall flow direction beneath the site was calculated to be to the northeast with a variable gradient. Groundwater contours for July 23, 2001 are presented on Plate 2. Prior to sampling, the depth to groundwater was measured in each well using a Solinst electronic water level indicator. The depth to groundwater measurements was used to calculate the volume of water in each well. Once calculated, approximately three well volumes of water were purged from each well using a two-inch submersible pump until temperature,pH, and conductivity readings stabilized and/or the water cleared of sediment. The water samples were then collected through the sampling pump. Sample water pumped from the wells was poured into appropriate sample containers provided by the laboratory. The samples were immediately placed in an ice-chest with ice and submitted under chain-of- custody to a California-certified laboratory for analysis of Total Petroleum Hydrocarbons (TPH) as gasoline using EPA test method 8015 modified,Benzene, Toluene, Ethylbenzene and Total Xylenes (BTEX)using EPA test method 8020/602 and Tert-Butanol,Methyl tert-Butyl Ether, Di- isopropyl Ether, Ethyl tert Butyl Ether, and Tert-Amyl methyl Ether(oxygenates)using EPA Method 8260B.