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REG 603 UPDATE-8 7/17/92 • specially designed bailer is lowered into the water to determine If gasoline product was floating on the water. If product is observed, product thickness is measured Ground water elevations are then recalculated to compensate for the decrease in pressure created by any observable vacuum at the wells and the weight of gasoline (floating product) , if measurable Monitor wells that contained gasoline product are then "purged" until depletion of the floating product is observed. Approximately a quart of gasoline was recovered by this method from MW1 on 11/27/90. The recovered product is presently being stared with the ground water produced from "purging" the monitor wells for sampling, on site in the 1000 gallon "ConVault". In order to "purge" each well, a dedicated disposable PVC 1 1/2" x 3 ' bailer was repeatedly lowered down the well and into the water Temperature, pH, and Conductivity was measured for every gallon removed. Bailing usually proceeds for each well until pH, conductivity, and temperature parameters stabilized (approximately 2 gallons) and then the sample is taken. During the June 18, 1992 sampling, monitor wells MW1 and MW3 contained clear-yellow floating product, as a sheen and 0.28' respectively. MW10 was • dry, no samples were obtained from those wells Monitor wells MW2 and MW7 depleted after approximately 1 to 1.5 gallons of water was removed, samples were then obtained of the recharge water from those wells. Monitor wells MW4, MW5, MW6, MW8 and MW9 were sampled after the temperature, pH and conductivity stabilized, see Appendix A - Sampling field notes The "purged" water is presently being stored in the 1000 gallon "ConVault", on site, within the fenced treatment compound. A representative water sample was obtained from the monitor wells using the dedicated disposable PVC bailer used during purging of the well. The water samples collected were stored in four--40 milliliter (ml) VOA vials These water samples were placed into an insulated cooler with ice and, in the clients behalf, "chain of custody hand delivered" to MATRIX ENVIRONMENTAL Laboratories, formerly Chemtech, (DHS certified #359) for chemical analyses 3.0 RESULTS 3. 1 PRODUCT AND RECOVERY During the initial site assessment and during subsequent site visits, floating product was observed in monitor wells MW-1, MW-3 and MW10 Product thickness in MW-1 has ranged from 0 01' to 1 26' and from 0 17' to 1.66' in MW-3 Only a product sheen has been observed in MW10; during the March, June and September, 1991 and the March 10, 1992 samplings The recovered gasoline is amber • yellow and appears to be fresh (no apparent degradation) PAGE 4