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31 August 2005 AGE-NC Project No 96-0232 Page 8 of 30 P24,P25,P28,P30,P31,P32,P34 and P35 samples at concentrations as high as 11,000µg/l Analytical results of grab ground water samples are summarized in Table 3 The area of the most intense MTBE-impact to ground water was encountered in the southwestern dispenser area,extending northward to the mini-mart and southwestward to the southwest corner of the subject property A report of findings (Quarterly Report - Second Quarter 2000, dated 19 July 2000) documenting investigation activities performed in April 2000 was prepared by AGE and submitted to the SJCEHD and the RWQCB • May 2000 - Six multi-level ground water monitoring wells (MW-8 through MW-13) were installed on and off-site to maximum depths of 150 feet bsg (Figures 2 and 3) Well construction details and boring logs for MW-8 through MW-13 are in Appendix F Twenty-three initial ground water samples were collected from wells MW-8 through MW-13 Laboratory analysis of initial ground water samples detected MTBE in seven samples at concentrations as high as 2,500 µg11 (MW-13A), TPH-g in five samples at concentrations as high as 130 µg/l, TPH-d in fourteen samples at concentrations as high as �} 940µg11, BTEX compounds in two samples at concentrations as high as 33 µg11, TAME in one sample at a concentration of 87 µg/l,ETBE in one sample at a concentration of 2 5 µg/l, TBA in four samples at concentrations as high as 24 µg11 and ethanol in 21 samples at concentrations as high as 1,200,000µg/l Analytical results of monitoring well water samples are summarized in Table 7 Due to the high concentrations of ethanol, which were detected only in samples collected from the multi-level monitoring wells, samples of the '/4-inch coated bentonite pellets (Sinclair Services) were submitted in a VOA container filled with bottled water for laboratory analysis for ethanol The laboratory analysis detected dissolved ethanol at a concentration of 22,000 µg11 (Appendix D) Thereafter,AGE requested MSDS sheets from Sinclair Services, as well as other industry bentonite pellet manufacturers from Colloid Environmental Technologies Co (CETCO) and Polymer Drilling Systems (Pel-Plug) The MSDS sheets from all three bentonite pellet manufacturers listed ethyl alcohol and ethyl acetate on the bentonite coating The high ethanol concentrations detected in samples from the multilevel wells appeared to be due to introduction of the bentonite pellets Interim remedial action was continued at the site by continuously pumping ground water from EW-1 at a rate of 2 gallons per minute and discharged into a 5,900-gallon poly tank Three grab ground water samples were collected during May 2000 from the EW-1 discharge, MTBE was detected at concentrations of 650 µg/l, 800 µg11 and 490 µg/l Analytical results of EW-1 grab samples are summarized in Table 7 Advanced GeoEnvironmental,Inc