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V. GROUND WATER DEPTH AND TESTING According to the map of "Lines of Equal Depth to Water in Wells" published fall 1990 by the San Joaquin County Flood Control and Water Conservation District, the depth to groundwater at this location is approximately 90 to 100 feet. There are two wells on the subject property. One is used for domestic use and is located next to the house. The other is for agricultural use and is located 420 feet north of the southeast corner of the property (or Parcel 2). A water sample was obtained from the domestic well (W1) on October 22, 1991. A' water sample was obtained from the agricultural well (W2) on October 31, 1991. The samples were submitted to the laboratory and tested for the presence of dibromo chloropropane (DBCP), which was a soil fumigant used in vineyards. A copy of the test results is contained in the Appendix. The results of the tests indicate that the level of DBCP in both wells are over the Maximum Contaminant Level (MCL) allowed by law. VI. SOIL PROFILE AND PERCOLATION TESTS A test pit was excavated to a depth of 10.0 feet in the area of a potential disposal field for the proposed Parcel 1. The purpose of the test pit was to determine the soil profile in the general area. For approximate location of the test pit, see the Tentative Parcel Map in the Appendix. The test pit was excavated with a Cat 416 backhoe equipped with a 24 inch bucket. Visual classification of each soil stratum encountered was made in the field by a civil engineer at the time the test pit was excavated. A description of each soil encountered is presented in the Appendix as Log of Test Pits. Generally the soils encountered in the test pit consisted of various gradations of medium dense sand with slight amounts of silt in the upper 3.5 feet. The sand became slightly cemented at a depth of 8.0 feet. For a more detailed description of the soil strata encountered see the Log of Test Pits. The surface silty sands should provide a good percolating stratum. A percolation test was performed in the area where the proposed leach field would most likely could be located. For approximate location of the percolation test see the Tentative Parcel Map in the Appendix. The percolation test was performed in an 8 inch diameter by 36 deep test hole. A 3 inch diameter perforated pipe measuring device was placed in the test hole and backfilled with 3/4 inch gravel. The hole was filled with water 24 hours prior to running the test. The last ten minutes of the test readings were witnessed by a San Joaquin County health official and the test data obtained is contained in the Appendix. The results of the test indicate that the soil at the proposed homesite on Parcel 1 had a percolation rate of 2.7 minutes/inch. 06�11 - 3