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_ Water Analysis The water table elevation varies from approximately 30 feet above sea level at the southeast comer of the site to approximately 20 feet above sea level at the north west comer of the site. The depth to the water table from the surface increases from south to north. The depth being approximately 100 feet below the surface at the south east comer of the site to a depth of approximately 110 feet at the north west comer of the site. The ground water gradient is to the northwest. This information was taken from data published -- by the San Joaquin County Flood Control And Water Conservation District titled Groundwater Report. Fall, 1994. The water quality varies slightly in the area,as referenced from water sample results at appendix III- A-D. Water sample test results that were taken near the site and at the site read as follows: Location: Sample# Test: Nitrate TDS {3 Abandoned domestic well 1001 1 at the George teVelde Dairy i across the street and parallel to the water gradient- TVI 13 mg/L 224 mg/L DW#1 the George WVeldcDarry— across the street and parlor to the water gradient. first test- TV2 13 mg/L 192 mg/L o r n we a e George teVelde Dairy, across the street And parallel to the water gradient- TV3 13 mg/L 224 mg/L -- southwest to the site and water gradient relative to the site- TVW-1 9 256 mg/L mesttc we run e c northeast to the site and water R gadient relative to the site- T V W-2 I 1 mg/L 356 mg/L o�e ttc- adient to the T V W-3 13 mgt 237 mg/L DW#1 George teVelde-across the Street and parallel to the water gradient- TVW-4 13 mg/L 218 mg/L irrigation well, down dient to the site- TV W-5 10 mg/L 154 mg/L Domestic well at the site 1 13 m Domestic well at the site JDSW2 13mg/L 154 mg/L The water quality changes only slightly in the general area, reference appendix IVA&B.Note that the water at the OID irrigation well has a slightly better test result.This could be due to extensive pumping which is drawing from high quality upgradient water, which in tum dilutes the nitrates and TDS contents. Based only on the test results from these ten wells and the fact that we are not sure from what depths or from what aquifer water samples have been pumped from,it is impossible to conclude with any degree of accuracy the source of the contaminates that are affecting the water quality. There are three major artificial water influences to the water table in the area: First,Were are a number of rice fields. They have a constant head of water during the summer growing season forcing elements down into the soil profile. Considering that Were is no appreciable wet-dry cycle during the rice growing season and the constant wetting of the soil from winter rains,Were is a constant flow of surface water penetrating into the water table. Consequently,any mobile elements, including nitrate,will be carried down to the water table given long periods(years)to farming rice. Second:the Farmington Reservoir. This body of water is approximately I mile to the northeast, northeast gradient to the site,and at the same water table elevation contour line. This force of water into ®Western Design/David Avila 2000 17