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Noe timate of the extent of the contamination can be obtained. The inner- most ring of sampling locations are located directly besides the ex- cavation while the outermost ring is within 15 feet of the first teir of boring locales. A sample shall also be obtained from the center of the excavation by using a hand held auger and coring down to the water table (the base of the excavation lies at approximately 16 feet) . Once the extent of contamination has been defined, the soil will be excavated and contained on site until their transport to an appropriate landfill. If necessary, the soil shall be aerated in accordance with requirements outlined by the San Joaquin County Air Pollution Control District. The hole created by the excavation will be filled with clean fill and compacted to minimize settling. Groundwater Monitoring Plan Two four-inch monitoring wells will be installed at the site to verify the direction of subsurface flow and to test for the existence of groundwater contamination. The estimated locations of the wells are shown in Figure 2 . Well MW-1 will serve as an upgradient well and provide backround water quality measurements. Well MW-2 will be placed downgradient of the excavation and will be within 10 feet of the trench. The wells will be drilled using 10-inch hollow stem augers. Based upon reported water table elevations and potential contaminants, the estimated well depths will extend to 35 feet. Perforated zones will extend above the highest estimated water table elevation to detect the presence of floating product. The borehole will be logged continuously using a 5-foot core barrel sampler and well casing shall consist of 4-inch diameter Schedule 40 Poly Vinyl Chloride casing (blank and perforated: See Figure 3) . After installation of the filter pack and annular seal, the cement will be allowed to set and the wells developed using a surge block and bail/pumping method. The tops of the wells will be covered with a lock- ing top steel cover whose top will be situated below ground surface. A manhole-like cover shall be placed over the well so that trucking oper- ations will not be disturbed upon completion of the drilling work. All well tops shall be surveyed by a California licensed surveyor to allow for accurate measurement of water levels in relation to sea level and proper verification of the subsurface flow direction. All drill cuttings shall be contained on site and disposed of in a proper manner. The augers will be steam-cleaned prior to their reuse to eliminate the potential of cross contamination. If the San Joaquin Local Health District (SJLHD) feels it is necessary to contain purge water, it will be stored in 55 gallon drums and trans- ported to an appropriate disposal facility. All personnel performing work at the site will conform to pertinent health and safety guidelines as required by the California Occupational Safety and Health Admin- instration and other local regulatory bodies. The existence of subsurface drainage ways, cables, water mains, etc. will be investigated prior to commencement of any drilling activity at the site (for soil sampling of well installation purposes) . BMI will contact USA locating service for assistance in the completion of this task.