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31 August 2005 AGE-NC Project No 96-0232 Page 6 of 30 seal for RDW-1 was set at 50 feet bsg and the gravel pack set around the casing from 50 feet bsg to total depth of the well Aquifer draw-down pump testing was performed at MW-1 (screened 9 to 24 feet)to evaluate general ground water aquifer characteristics, from pump testing,transmissivity values were calculated between 135 and 932 gal/day-ft A six-inch diameter ground water extraction well(EW-1)was installed on-site to a depth of 33'/2 feet bsg for interim remediation measures (Figures 2 and 3), well construction details and a boring log for EW-1 is in Appendix F,no soil or ground water samples were collected during installation of EW-1 Five cone penetrometer testing(CPT)soil borings(P 13 through P1 7)were advanced on-site to characterize the geological and hydro-geological framework and to assess preferential migration pathways CPT soil boring locations are depicted in Figures 2 and 3, CPT boring logs are in Appendix F Based on soil composition data obtained from the CPT soil borings P 13 through P17,cross sections C-C',D-D'and E-E'were constructed depicting the general subsurface soil composition on-site and off-site(Figures 7, 8 and 9,respectively) Based on the soil characteristics data obtained by CPT investigation, AGE defined five informal hydrogeologic units First Zone (10-35 feet bsg), Second Zone (40-60 feet bsg), Rocky's Upper Zone (70-75 feet bsg), Secondary Aquifer Zone (90-110 feet bsg), and Primary Aquifer Zone (130-150 feet bsg) On 01 March 2000, the RWQCB issued Cleanup And Abatement Order No 05-00-700 which ordered Flag City Chevron to immediately provide Rocky's Restaurant with an alternate source of drinking water and to investigate and remediate the contamination originating from the Flag City Chevron USTs A copy of Cleanup And Abatement Order No 05-00-700 is in Appendix C A report of findings (Quarterly Report -First Quarter 2000, dated 01 May 2000) documenting investigation activities performed in March 2000 was prepared by AGE and submitted to the RWQCB and the SJCEHD • April 2000 - Grab ground water samples were collected adjacent to CPT soil bonngs P13, P14, P15, P16 and P17 Dissolved MTBE was detected from P16 (near Rocky's domestic water well) at depths between 37 and 40 feet, 53 and 56 feet, 70 and 73 feet and 87 and 90 feet at concentrations of 270 µg11, 280 µg11, 55 µg/l and 6 µg/1, respectively Dissolved MTBE was detected from P 17 (near northwest Rocky's Restaurant property boundary) at depths between 37 and 40 feet, 55 and 58 feet and 80 and 83 feet at concentrations of 110µg/1, 150 gg/1 and 4 9µg/1,respectively Dissolved TBA was detected from P 16 at depths between 37 and 40 feet and from P17 at depths between 111 and 114 feet at concentrations • of 6 gg/l and 7 1 pg/l, respectively Dissolved methanol was detected from P13 at depths Advanced GeoEnvironmental,Inc