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NWAV, \Nse Health Services, Environmental Health Division and the California Regional Water Quality Control Board indicated that their oversight would not be provided. On September 7, 1995 Ground Zero performed additional subsurface investigation at the request of Mr. Ranuio in anticipation of commercial development of the property. Ground Zero supervised the drilling of three soil borings (SBI, SB2, and SB3). SB1 was advanced in the vicinity of the former tanks and dispenser island. SB2 and SB3 were located progressively further from SB1 in the assumed downgradient direction, northeast of the former tanks. The location of the borings are shown on Figure 2. Drilling was performed by V&W Drilling (C57-710678) under permit from PHS/EHD. Ms. Linda Turkatte of PHS/EHD was present to observe field activities. Field observations and analytical results of soil samples collected from the capillary fringe zone in each soil boring indicated that the soil excavation performed in 1990 successfully removed impacted soil in the unsaturated zone. Grab water samples collected from borings SBI and SB3 suggested that groundwater contamination is limited to a relatively localized area in the vicinity of the former tanks. Laboratory results are summarized in Table 1. PROPOSED SCOPE OF WORK Ground Zero will supervise the drilling of five soil borings in the vicinity of the former tanks and dispenser island. One boring, located hydrologically downgradient from the former tanks, will be converted to a groundwater monitoring well. The locations of the proposed borings and monitoring well are shown on Figure 3. Drilling will be performed by V&W Drilling (C57-710678) under a current drilling permit. Three borings, located north, south, and west of the former tanks, will be drilled to approximately 20 feet below grade. Soil samples will be collected at this depth, which should represent the capillary fringe zone, for laboratory analysis. A fourth boring will be advanced in the approximate center of the former excvation to attempt to determine the vertical extent of soil contamination. Soil samples collected from the borings will be analyzed by State -certified Argon Laboratories (FLAP #1873) for total petroleum hydrocarbons as gasoline (TPHg) using EPA Method 8015; and benzene, toluene, ethylbenzene, and total xylenes (BTEX) using EPA Method 8020. If appropriate, selected soil samples collected from the borings will be analyzed for physical parameters including vertical permeability, effective porosity, moisture content, bulk density and particle size distribution. Selected soil samples collected from the borings will also be analyzed for chemical/biological parameters including total organic carbon (TOC); heterotrophic plate count; and phosphorus, potassium, nitrogen (PKN)- Subsequent to soil sampling, a discrete water sample will be collected from the perimeter borings (with the exception of the boring to be converted to a groundwater monitoring well) using a Hydropunch II water sampler. The water sample will be collected by driving the Hydropunch II implement into the water table using a 140 -pound drop hammer and allowing groundwater to flow into the screened portion of the sampler under natural hydrostatic pressure. The water sample will be collected using a pre - washed bailer into appropriate containers supplied by the laboratory. The sample will be labelled, placed on ice, and transported to Argon Laboratories for analysis. gramdzi\1ane\nnuio.wk2 2