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wooden barn, several abandoned wooden chicken coups, and a small sheet metal storage shed with an abandoned automobile and miscellaneous autoparts. Features of environmental note at the main compound include three above ground diesel tanks, an single above ground gasoline tank, above ground water tanks, an on-site groundwater production well, and three underground septic tanks. The remaining portions of the property are essentially open farmland currently under cultivation. The predominant crop is oats with minor amounts of alfalfa also being grown. The subject property is located along the eastern flanks of the San Joaquin Valley. The topography has a natural slope from a high of 220 feet above mean sea level (MSL) at the southwest corner as per the USGS Topographical Map, Midway Quadrangle (1953-photorevised 1980) to 80 feet above MSL at the northeast corner as per USGS Topographical Map,Tracy Quadrangle (1954- photorevised 1981). The surface geology of the subject site is mapped as Quaternary alluvial fan deposits as per the Geologic Map of the San Francisco -San Jose Quadrangles (1991). The alluvial fan deposits consists of varying mixtures of gravel, sand, silt and clay. These deposits are underlain of older sedimentary deposits which are over several hundred feet in thickness. Surface soils exposed on the subject property generally consisted of brown clayey silt with some sand and gravel. Based on hydrogeological reports in the area, groundwater is expected to occur at approximately 50- feet below ground surface (bgs)but will vary as does the site's surface topography. Based on the site's surface topography, the groundwater flow direction is assumed to be to the northeast. The regional groundwater flow direction is generally believed to be towards to the west towards the San Francisco Bay through the San Joaquin Delta. The San Joaquin County Flood Control and Water Conversation District Map (1996) does not show any groundwater contours in the vicinity of the subject site indicating a very flat groundwater gradient. II. PURPOSE AND SCOPE OF WORK The purpose of this investigation is to characterize the nature and extent of the petroleum and metal contamination in the site's soils. The scope-of-work presented in this workplan,consists of the following tasks: 1) Prepare this written workplan and the attached site specific health& safety plan for conducting a subsurface investigation at the site. Submit the plans to the lead regulatory agency, the SJCEHD for agency review and permit approval. 2) Engage the service of Underground Service Alert (USA) and a private underground utility locator to locate and clear underground utilities within the proposed investigation area so that the potential of accidental damage to underground utilities will be reduced. 3) Retain the service of a licensed drilling contractor. Advance up to 13 borings around the site to depths between 8 and 12 feet below the ground surface. The borings will be 2