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i Groundwater elevation data suggests an irregular groundwater surface exists beneath the site The groundwater flow net beneath the site historically has vaned considerably. The irregularities in the measured depths-to-water may be due to the heterogeneous nature of the soils and/or the varying well depths. A groundwater gradient map for the December 8, 1994 monitoring event is presented on Plate 2. Groundwater samples were collected from wells MW2, MWS, and MW6, after purging at least three casing volumes of water or purging dry No sample was collected from well MW i due to the presence of free product Monitoring wells were purged and sampled according to RESNA's Quality Assurance/Quality Control Plan (on file with PHS/EHD) Well purge logs are included as Attachment 1. LABORATORY ANALYSIS Groundwater samples were transported under chain of custody protocol to Sequoia Analytical Laboratory in Redwood City, California (ELAP #2000) for analysis of benzene, toluene, ethylbenzene, and xylenes (BTEX) utilizing EPA method 8020, total petroleum hydrocarbons as gasoline (TPHg) and as diesel (TPHd) utilizing EPA method 8015 modified No samples were analyzed for halogenated volatile organics (HVOCs) due to an inadvertent oversight Laboratory analyses of the sample collected from well MW2 detected TPHd at 300arts per P billion (ppb) The sample from monitoring well MW-5 contained a detectable amount of benzene (2 1 ppb), TPHg (200 ppb) reported as a non-gas mix, and a non-diesel mix of 110 ppb in the TPHd range No petroleum hydrocarbon analytes were detected above method detection limits in the sample collected from monitoring well MW6. Analytical results of petroleum hydrocarbon constituents are summarized in Table 2. Historical analytical results of HVOCs are summarized in Table 3. Laboratory data sheets and chain-of-custody documentation are included in Attachment 2 1500771QUARTLYI4QR-1994 doe 2 (C9'sm@Mn-@Env 1 ronmenta l