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Criterion 2: Separate phase product has been removed to the extent practicable. GEOMATF7IX There is no recoverable separate phase product at the site; however there is a petroleum sheen in temporary well TW-2. This sheen is comprised of "globules"of residual petroleum (i.e., highly degraded crude oil). Site data indicate that the residual petroleum at the site, including the petroleum sheen, ' does not contain significant amounts of soluble petroleum constituents, and that the beneficial use of site groundwater is not impacted. Groundwater samples collected downgradient from the residual petroleum in soil and sheen do not t contain petroleum constituents at concentrations greater than WQOs. This indicates that petroleum sheen is not providing a source of dissolved petroleum constituents to groundwater and is not degrading groundwater quality. Criterion 3: No existing water supply wells, deeper aquifers, surface waters or other receptors are threatened by pollutants remaining in the aquifer. No dissolved groundwater"pollutants" are present and no petroleum plume ' exists. Therefore, existing water supply wells (if present), deeper aquifers, or surface waters will not be adversely affected by residual petroleum at the site. Criterion 4: The total pollutant mass remaining in the ground water is decreasing at ' predicted rates and neither creates, no threatens to create, a risk to human health and safety or future beneficial use(s) of the aquifer. Current groundwater monitoring data indicate groundwater quality meets drinking water WQOs and,therefore, the beneficial use of site groundwater is ' not impacted; a petroleum hydrocarbon plume, or a"pollutant mass," does not exist. Furthermore, it has been established that site conditions do not pose a risk to human health and safety (Geomatrix, 1998) and that institutional controls currently in place would limit the use of the relatively shallow groundwater at the site (approximately 7 feet bgs). Shallow groundwater is often regulated as a potential source of drinking water per State Water Resources Control Board ' Resolution 88-63, even though other sources of contamination (such as leaking sewers, nitrates from agricultural activities, etc.) may exist and local and state \\st3\deptdaM\Doc_SafeA780.01\clsrrpt.doc 7