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rt�rr.�.A Working to Restore Nature I groundwater beneath the site Data collected from the three wells during previous monitoring events is presented in 'fables 1 and 2. In addition, water quality data for a nearby onsite domestic water well is provided in Table 1 In October 1993, RESNA observed drilling of two offsite and four onsite soil borings (HP-1 through HP-6)to groundwater(RESNA,January 26, 1994,Report 123020 01) Groundwater samples were collected from these borings using a Hydropunch sampling device RESNA also observed drilling of three additional soil borings onsite (B-1, B-2, and B-3), these borings were converted to vapor extraction wells (VW-1, VW-2, and VW-3) Residual gasoline hydrocarbons were detected in soil from borings drilled near the tank complex(B-1, B-2, and B-3) but were not detected in the other onsite or offsite borings Dissolved gasoline hydrocarbons were not detected in groundwater from onsite or offsite borings GROUNDWATER MONITORING, FIRST QUARTER 1994 On December 30, 1993, a technician from RESNA measured the depth to water and subjectively analyzed groundwater samples from the four monitoring wells (Table 1) The technician noted floating product and sheen in wells MW-1 and MW-2, respectively Groundwater samples were collected from wells MW-2 and MW-3, well MW-1 was not sampled because it contained floating product Our field procedures are described in an attachment to this report. The surveyed elevations and the depth-to-groundwater measurements, summarized in Table 1, were used to evaluate the potentiometric surface beneath the site The groundwater flow direction on December 30, 1993, was to the northeast with the hydraulic gradient of 0.002 (Plate 3) The water samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg) using modified Environmental Protection Agency(EPA) Method 8015 and benzene,toluene, ethylbenzene, and total xylene isomers (BTEX) using EPA Method 602 The samples were analyzed at Sparge Technology, Inc. in Sacramento, California (Hazardous Waste Testing Laboratory Certificate No 1614) Results of analyses indicated TPHg and BTEX concentrations were below laboratory detection limits in well MW-3. TPHg and benzene were detected in well MW-2 at concentrations of 14,000 parts per billion (ppb) and 1,000 ppb The results of analyses are summarized in Table 1 Copies of the laboratory Analysts Reports and Chain of Custody Record are attached 02011soV123MO-1 2