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w F OUNDWATER TEST RESULTS the water table was measured with an electronic water level meter in the test boringately I I feet below existing grade. As referenced, a groundwater sample wasom this soil test boring for analysis. Static groundwater depth of 11 feet as determined in the test boring corresponds with the 1999 Lines of Equal Depth to Groundwater map. From the 1999 Lanes of Equal Elevation of Groundwater, the groundwater elevation is indeterminable. The 1992 Lines of Equal Elevation of Groundwater show the groundwater to be at 0 ft MSL. Directional flow appears to be gradually west,toward the San Joaquin River Delta. The weight of soil that supports the Highway 120 Bypass may be influencing the groundwater directional flow and velocity. The Bypass embankment is directly adjacent to the north of the subject property. Groundwater influence from the soil weight, which is significant, could only be determined with highly sophisticated groundwater monitoring. A. Underlying Groundwater Test Results The groundwater sample from the exploratory boring,retrieved with a stainless steel bailer, reveals a nitrate (as nitrate)concentration of 7 mg/L (ppm), which is approximately one-sixth the Maximum Contaminant Level (MCL) of 45 ppm (as nitrate.) The pH was taken in the field and found to be slightly alkaline at 7.5. Alkalinity was measured at a relatively high 329 ppm and Total Dissolved Solids (TDS) a medium-high concentration of 508 ppm. It is our understanding that the project will receive domestic water from an on-site well, to be drilled at the north side of the project and more than 400 feet away from the wastewater disposal area. The two wells that are on the Cunha Draying property (APN 241-410-37) were sampled for the constituents referenced above and for the agrichemicals DBCP and EDB. The domestic water well source was sampled from a hose bibb at the wellhead, and shows a nonexistent nitrate concentration of Below Detectable Limits(BDL). TDS was measured at 280 mg/L. The analytical test results for the irrigation well (fire suppression well) for all constituents tested closely resembles the groundwater(water table) sample results. A well log does not exist for this well, so the screened depth is unknown. It is theorized that this well is screened high in elevation and there is no grout seal. This irrigation well was sampled at the fire hydrant, north of the Cunha facility, after purging. Agrichemical DBCP and EDB samples were placed in VOA bottles with preservative. Test results reveal BDL for the agrichemicals, or non-detect in both sampled wells. Total Alkalinity is a relatively low 143 ppm in the domestic well, but over twice this concentration in the irrigation well(326 ppm). There must be a subsequent loss of 7.1 mg of alkalinity in the wastewater for every milligram of ammonium oxidized to nitrate. The following Section discusses the role alkalinity plays in nitrification. Page -4- C(ew e CowuhiV