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(§ 4.0) LOCAL GROUNDWATER AND SURFACE WATER INFORMATION (§4.1) The 1999 Lines of Equal Depth Map published by the San Joaquin County Flood Control illustrates the groundwater depth to be approximately 55 feet below ground surface(b.g.s.). The 1999 Lines of Equal Elevation Map illustrates the groundwater elevation and the directional flow to be in northeast direction under the subject property, and then turning to a northerly direction. A Well Driller's Log exists for one of the on-site domestic wells. (§ 4.2) The underground lithology specific to the subject property consists of sand, shale, clay, and gravel. There does not appear to be significant clay strata between the surface and the static water level, which may explain the propensity for nitrate contamination of the underlying groundwater. The property is not subject to 100-year flooding. Therefore, it is highly unlikely there would be surfacing of effluent from inundated conditions. (§4.3,4.4 and 4.5) The first water sample was obtained from a hose bibb next to the pressure tank of the domestic well that serves a residential structure and a farm labor mobile home at the north end of proposed Parcel 4. This hose bibb is directly south of the mobile home, while the actual well is directly west of the residential structure. A second water sample was taken from the well that serves Mr. Vander Beek's residence on proposed Parcel 1. This sample was taken from a hose bibb directly west of the pump house, directly east of the residential structure. Another domestic well exists approximately 25 feet to the east of this well; however, it is inoperable and could not be sampled. These wells and sample locations are denoted on the Tentative Map found in Appendix B. After each well was allowed to cycle three times to ensure the sampling of aquifer formation water, three VOA amber glass bottles for each well (with Sodium Thiosulfate preservative)were filled completely with water so that there was no head space. A one-half liter plastic bottle was used for the nitrate analysis from each well. (§ 4.6) The sample was placed in a cooled ice chest and transported under the attached Chain of Custody to A&L Labs in Modesto, California to be analyzed for nitrate and DBCP/EDB. Water analysis reveals high nitrate concentrations of 103 ppm for the Parcel 1 well and 58 ppm nitrate for the Parcel 4 well. The Maximum Contaminant Level (MCL) for nitrate (NO3) in drinking water is 45 ppm. These high concentrations can unquestionably be attributed to the intense agricultural production in this area for the past six decades. Page -4- �Ji Chesney Consulting