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�.. On November 28, 2000, Ramage Environmental published Environmental Site Investigation ., Report documenting the results of a sensitive receptor surrey and the drilling of confirmation soil borings (CPT-1 and CPT-1A) using a cone penetration test (CPT) drilling rig. To delineate the vertical extent of impacted groundwater, discrete groundwater samples were collected at 75, 90, and 125 feet bgs from CPT-1, located approximately 20 feet northeast (downgradient) of the former USTs. Concentrations of MTBE declined significantly with depth �.r and were absent in the 125-foot groundwater-bearing interval. Only 1,2-dichloroethane (1,2- DCA) was detected in the 125-foot groundwater sample, at a low concentration of 0.5 micrograms per liter (µg11). The soil boring locations are shown on Figure 2, the soil sample analytical results are summarized in Table 5, and the groundwater analytical results are included in Table 6. �. According to available records, three property parcels within 2,000-feet of the site had operating water wells. These properties included the San Joaquin Catholic Cemetery (site), St. Joseph's Hospital, and a residential dwelling at 1821 North Hunter Street. The locations of the cemetery wells and hospital well are shown on Figure 4. On May 2, 2002, Ramage Environmental published Report, Additional Site Investigation, which documented the drilling of CPT borings for discrete groundwater sampling at six additional locations, and the installation of a two-well monitoring well cluster(MW-8A and MW-$B). The results of the project indicated that the extent of MTBE was defined and limited to the groundwater table northeast (downgradient) of the former UST. Only low concentrations (0.5 to 1.2 µg/l) of 1,2-DCA were detected in the 110 to 125 foot groundwater- bearing interval south and west of the former UST. The CPT boring and monitoring well r locations are shown on Figure 3, the monitoring well construction details are summarized in Table 2, the monitoring well groundwater analytical results are included in Table 3, and the groundwater analytical results from the CPT borings are summarized in Table 6. 1.2.5 Groundwater Remediatiort By Batch Extraction Between January 18, 2003 and August 25, 2004, Ramage Environmental supervised the monthly batch extraction of groundwater from MW-5 and MW-7. The total volume of groundwater extracted during the seven extraction events was approximately 16,710 gallons. After seven monthly groundwater extraction events, the concentration of MTBE increased from 92 to 100 µg11 in MW-5, and decreased from 390 to 100 µg11 in MW-7. In the same �. period, the concentration of 1,2-DCA decreased from 26 to 13 µg11 in MW-5, and decreased from 25 to 8.2 µg11 in MW-7. The groundwater extraction analytical results are summarized in Table 7. 7