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Status Report ARCO Facility No 6100 Tracy,Caiiforrua Page 4 began Table 1 presents the measured product thickness and quantities of product removed from the well The measured product thickness ranged from 0 39 to 147 feet The total amount of product removed during the first quarter 2001 was approximately 10 5 gallons Gasoline and water recovered from monitoring well MW-1 is being stored on site in DOT-approved 55-gallon steel drums pending disposal Delta will continue to bail product from MW-1 on a weekly basis On February 7, 2001, a Delta technician bailed approximately 2 gallons of floating product from MW-1 and began well development using a 4-inch diameter PVC bailer The bailer was lowered to the bottom of the well and surged up and down within the water column for approximately 10 minutes The well was then purged dry (approximately 20 gallons purged) and allowed to recover On February 8, 2001, free product (0 04 feet) was again bailed off and the well was purged dry During recovery, depths to groundwater measurements were frequently recorded to evaluate the recharge rate into the well It required over 4 5 hours to achieve approximately 70% recovery Table 2 presents the depth to water and product thickness measurements recorded over the recharge period MONITORING OF WATER IN VAPOR EXTRACTION WELLS Delta has identified six vapor extraction wells onsite (VW-1 through VW-6) that contain rechargeable groundwater Depth to groundwater was measured in these wells on several events during the first quarter 2001 All other vapor extraction wells are either dry or contain only a small amount of water that is not rechargeable, likely the result of moisture that has accumulated in the bottom of the well These vapor extraction wells were monitored during one event (February 7, 2001) to the first quarter, 2001 Table 3 presents the depth to water measurements in the vapor extraction wells that were recorded during the first quarter 2001 Free-phase floating product was present in vapor extraction well VW-1 on three monitoring events at a maximum thickness of 0 01 feet The product was removed from MW-1 using a bailer and stored onsite The six vapor extraction wells will continue to be monitored on at least a monthly basis The remaining vapor extraction wells will be monitored quarterly GROUNDWATER SAMPLING AND ANALYTICAL RESULTS Water samples were collected from various wells during the first quarter 2001 Each sample collected was appropriately labeled and stored in an ice-chilled cooler The samples remained chilled until relinquished to Sequoia Analytical, Inc , (Sequoia) a California state-certified analytical laboratory, for chemical analysis Strict chain-of-custody procedures were followed from the time the samples were collected until the time the samples were relinquished to the laboratory Laboratory analytical . results are presented in Table 4 and certified analytical reports with chain-of-custody documentation is included in Appendix B