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4. 1 SOIL AND GROUNDWATER CONDITIONS Mr. La Mont Harrison of Valley Drilling in Galt, California, provided information on soils in the vicinity of the property. Mr. Harrison said that he has installed four wells within 3/4 mile of the property and that they all exhibited the same general soil profile. He described the soil profile as clay soils having a horizon with "river sand" starting at 12 to 15 feet below ground surface (bgs) and terminating at 22 to 25 feet logs. He also reported that groundwater was encountered approximately 80 feet bgs and that no hardpans were present between the surface and groundwater. 4.2 ON-SITE WELLS The existing well at the property was drilled in 1976 to a depth of 136 feet bgs. As part of the process to convert the property to church use, the existing well was drilled deeper to a depth of 200 feet. This well is located approximately 100 feet from the nearest seepage pit that is part of the existing septic system. The well will be used for landscape irrigation. A new well was constructed approximately 80 feet northwest of the existing well. The new well was drilled to 300 feet and had a grout seal placed from ground surface to 100 feet. The new well will supply water for domestic use. A copy of the well log is attached (Appendix C). 4.3 GROUNDWATER TEST RESULTS The existing well as sampled on June 17, 1994, and analyzed for coliform bacteria, nitrate, and DBCP. Coliform bacteria and DBCP were not detected. Nitrate (NO.) was reported to be 19 mg/L. A copy of the test results is attached (Appendix C). 5.0 SOIL SUITABILITY EVALUATION Surface soils at the property were evaluated by excavating two trenches using a backhoe, examining the soil in the sidewalls, and then performing a percolation test in the area of the trenches. The test pits are described in Section 5.1 , and the results of the percolation test is presented in Section 5.2. Section 5.3 presents a general description of septic system designs in the vicinity of the property. Diagrams of the soil profiles are presented in Appendix D. SAC 125.12 5 DAMES & MOORE