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o The shallow ground water flow direction beneath the site is toward the north/northwest, with an average gradient of 0.004 foot per foot. t o The extent of adsorbed-phase hydrocarbons in the soil offsite, if present, has not been assessed. Residual absorbed-phase petroleum hydrocarbon constituents in the soil offsite, if any, may be to the north and northwest of the property, in the general direction of ground water flow. o Analysis of the water samples collected acted during this investigation indicates no detectable concentrations of petroleum hydrocarbon constituents, organic lead or fecal coliform, with the exception of the sample from AW-3. Detectable concentrations of TPH-D, TPH-G and BTEX were present in the sample from AW-3, however, the concentrations of any of the BTEX constituents detected do not exceed any of the corresponding state primary maximum contaminant levels (MCLs ) for drinking water. PROPOSED SCOPE OF WORK . The proposed Supplemental Site Investigation will be conducted in accordance with applicable regulations and guidelines of the San Joaquin County Environmental Health Services (SJCEHS) and the California Regional Water Quality Control Board, Central Valley Region (RWQCB) . To properly address the petroleum hydrocarbons detected in soil and ground water in the vicinity of the site, the proposed scope of work has been divided into two parts: Part 1 - Supplemental Subsurface Investigation Part 2 - Ground Water Monitoring and Sampling The tasks included under each part of the proposed scope of work are described below. P ET L- -. SUPPLEMENTA-L SUBSU F CE IMS GATTnu Part 1 will involve supplemental subsurface investigative work to define the nature and extent of hydrocarbons in soil and ground water downgradient and in the vicinity of the site. The tasks proposed herein also include a detailed review of available information and reports on any past or ongoing subsurface investigations at the nearby sites. i