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FJZJ . Working To Restore Nature groundwater monitoring data (March, 1992) determined groundwater flow direction to the south. A detailed discussion of the initial subsurface investigation can be found in RESNA's "Interim Problem Assessment Report, Soil and Groundwater Contamination, " dated June 8, 1992. In July 1994, a RESNA field geologist observed the drilling of four additional groundwater monitoring wells (MW4, MWS, MW6, and MW7) at the site to further characterize subsurface conditions Groundwater samples collected from these additional wells contained no detectable petroleum hydrocarbons. A detailed discussion of the Phase 2 Subsurface Investigation can be found in RESNA's "Summary Report, July 1994 Investigation, " dated August 26, 1994 GROUNDWATER MONITORING AND SAMPLING RESNA personnel performed groundwater monitoring and sampling on October 27, 1994. Field work consisted of measuring the depth-to-water in wells MW1, MW2, MW3, MW4, MWS, MW6, and MW7 using an electronic water/product interface probe to determine if free product was present; purging and sampling the wells; and subjectively evaluating collected water samples for the presence of petroleum hydrocarbon constituents Static groundwater elevations were measured in each monitoring well on October 27, 1994. Groundwater exists at approximately 13 to 14 feet below grade A groundwater gradient map is presented on Plate 2 Plate 2 depicts a northwest groundwater gradient of 0 001 ft/ft or approximately 5 feet/mile Fluid level measurements indicated groundwater flow direction beneath the site during the fourth quarter was consistent with the last monitoring event. Groundwater monitoring data is summarized in Table 1. On October 27, 1994 groundwater samples were collected from monitoring wells MW 1, MW3, MW4, MWS, MW6, and MW7 Samples were collected after stabilization of pH, electrical conductivity (EC), and temperature All wells monitored were purged and sampled according to RESNA's Quality Assurance/Quality Control Plan on file with the PHS/EHD. A minimum of four casing volumes of water were removed from each sampled well Purge water was contained in labeled DOT approved 55 gallon drums and stored on site pending laboratory analysis and proper disposal A dedicated disposable bailer was used to collect each water sample. No sample was collected from well MW2 for laboratory analysis due to the presence of floating product. Field parameters and purged volumes are shown on well purge logs included in Attachment 1 LABORATORY ANALYSIS Collected groundwater samples were placed on ice and transported under chain-of-custody protocol to state-certified Argon Mobile Labs in Ceres, California (DOHS Certification No. 1873). Samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg), benzene, 1500911QUARTLYI4QR-1994 doe 2