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REG 603 UPDATE-8 7/17/92 • A 2. GROUND WATER: JUNE 18, 1992. The sample results from the June 18, 1992 sampling shows a continued decline in the ground water plume, see Figures 5A and 5B and Table l MW9 has declined from 470 ppb gasoline range hydrocarbons to 56 ppb and benzene has likewise declined from 4.3 ppb to 3 3 ppb. MW1 and MW3 still exhibit floating product as a sheen and 0.28 feet respectively and MW2 has remained the same as the previous sampling, due in part to vapor extraction being concentrated on this well. The only increase in contaminate levels occurred at MWS which increased an TPHg from 7.6 ppm to 15 0 ppm, benzene from 3 2 ppm to 3.7 ppm, toluene 0.97 ppm to 2.5 ppm, ethylbenzene from below detection limits to 0 25 ppm and the xylenes from 0 37 ppm to 0.53 ppm. The remaining monitoring wells were all below detection limits A. 3. FECAL COLIFORM • Monitor wells MW2, MW3, MW4, MW5, MW7 and MWS were sampled on December 17-18, 1991, January 21, 1992, and February 4, 1992, for analysis of fecal coliform. These samples were placed into 500 ml plastic containers and hand delivered that day to F G.L. Environmental Laboratories for Fecal Coliform Analysis The December, 1991 sampling showed MW-2 tested at 16 MPN/100 ml, while MW-3 and MW-8 test >16 MPN/100ml. All other wells wells tested below detection limits of 2 2 MDL/100ml All wells (MW-2, MW-3, MW-4, MW-5, MW-7 and MW-8) tested below the detection limits of 2 2 MPN/100m1 from the January, 1992 sampling The February, 1992 results showed MW-2 and MW-3 at >16 MPN/100ml, MW-4 and MW-B- at 5 1 MPN/100ml, MW-7 at 2.2 MPN/100ml and MW-5 X2.2 MPN/100ml. During the June 18, 1992 sample visit, MW-2, MW-4, MW-5, MW-7, and MW-8 were sampled for Fecal coliform All wells tested below the detection limit of 2.2 MPN/100 ml. B. SOIL: As has been shown in the "Update Status Report, February 23, 1990" soil contaminated with gasoline range hydrocarbons exists beneath the underground storage tank excavation from the 25 foot depth to top of ground water and at the 40 foot depth to top of ground water around monitor well MW10 The capillary fringe area (50 foot depth) shows the spreaa of contaminant out to monitor wells MW1, MW2 and MW3, see Fence Diagram Figure 6 • PAGE 6