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I HAUTULOWUNU Quarterly groundwater sampling confirmed that residual contamination is present in monitoring well MW-2A. Groundwater samples collected from well MW-9 only contained d.6 Pg/L dhylbemmre detected in once in May 1999. A soil sample collected from the bodam of boring Bf1-13, d 65.5 feet bgs, contained 1 .4 mghg total petroleum hydrocarbons as gas Cl'Pll-g) and 0.017 mglkg brume. Maximum homene concentrations (37 mg/kg) were detested in the and sample collected from 45.5 feet where groundwater was first encountered. Petroleum hydrocarbon concentrations detected in the soil samples significantly decrease at depth. In January 1998, a CAP was submitted to CHIP, The purpose of the CAP was to provide an assessment or the impacts and, throw an evaluation of potential alternatives, select a proposed action that would adequately protect human health, safety, and the environment and that would restore or protect current or potential beneficial uses of water. Capital Projects selected the Intrinsic Remediatinn with Monitoring alternative as the most cast effective and least disruptive alternative available for die site. Receptors were net identified and therel'om, site sine fic risk- housed cleanup levels were not developed. From 1998 to 2005, a quarterly groundwater monitoring program was conducted at the site for wells MW-2A, MW-3A, MWA MW-5, MW-6, MW-7, MW-8, and MW-9. Regional groundwater elevations rebounded drum the 1988 decline, enabling well M W-2 to be reinstated into the sampling program. In June 2000, groundwater samples were additionally aralyzed for the following fuel additives: methyl tertiary butyl ether (MTBE), di-improryl ether, ethyl tertiary butyl ether, tertiary amyl methyl ether, and nothery butyl alcohol. The time subsequent monitoring events only included MTBE as an additional analyte. No fuel additives were detected in the groundwater samples. In 20W,the 199R CAP was revised and resubmitted to the E1 ID. 'I he revised CAP recommended Unit data gaps still remain that need W he addressed prior m considering the site for a low risk closure. The data gaps identified were the uncertainty orthe groundwater flaw direction and that The vertical and lateral extent orrontamination may net be entirety defined.