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as a I f fLuent Water Saniple On September 20, 2001, ASE collected an influent water sample (INF 09- ' 20-01) This sample was analyzed by Kiff Analytical of Davis, California (ELAP #2236) for a full scan EPA Method 8260B The analytical results f o r this sample are tabulated in the Tables Section of this report as Table One ' The influent water sample analytical report and chain of custody record is attached in Appendix B A graph showing the historical TPH-G ' concentrations in the influent water samples is attached in the Graph Section of this report ' Monthly Fuel Recovery—-Calou�l tl.nns The influent TPH-G concentration was used to calculate the estimated mass removed from the site during the month based on total gallons ' treated The Monthly Performance Log is presented as Table Two in the Tables Section of this report It shows that based on the number of ' gallons extracted in the month of September 2001, which was 170, 186 gallons, and assuming a constant TPH-G concentration of 57,000 parts p e r billion in the influent water stream, the system recovered 13 16 gallons of ' gasoline from the groundwater beneath the site To date, it is estimated that 125 05 gallons of gasoline have been removed from the subsurface DOWNGRADIENT MONITORING WELTS ' Monitoring wells MW-13, MW-14, MW-15, MW-16, and MW-19 are sampled every 4 to 6 weeks to track the hydrocarbon concentrations of the groundwater downgradient of the recovery wells These wells are ' located across West Yosemite Avenue approximately 90 feet downgradient of the recovery wells, and are the closest observation points to determine if the plume leaving the site is being remediated Since the start-up of the ' interim groundwater remediation system, hydrocarbon concentrations within these monitoring wells have generally dropped one to two orders of magnitude Since the discovery of free-floating hydrocarbons, only monitoring well MW-13 has shown a slight increase in hydrocarbon concentrations FREE-FLOATING PRODUCT IDENTIFICATION During field activities on June 14, 2001, ASE identified free-floating hydrocarbons on the groundwater surface in monitoring wells MW-5 and MW-6 and piezometer P-4 The product was subsequently identified as ' aged gasoline Since its discovery, product has been identified in the NES system tank floating on the water surface ASE has been removing this ' product from the NEEP tank and storing it on-site in a drum for future off- Frank's One Stop Remediation System Monthly Report — September 2001 ' -3-