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D. GROUNDWATER INFORMATION NLS§2.1, SSS§4.1. Groundwater depths and elevations throughout San Joaquin County are illustrated on maps published by the County Flood Control and Water Conservation District. The Lines of Equal Depth Maps indicate the water table may rise to 30 ft which would make the maximum depth of a sump system 10 ft. The Lines of Equal Elevation Maps groundwater directional flow is in a northeasterly direction. NLS§2.2,3.1, SSS§ 2.1,4.2. Properties to the north, south, and west are currently commercial, industrial and residential. Considering that this area was farmed for decades, there is a potential for nitrate contamination. NLS§2.3, SSS§ 4.3, 4.4,4.5,4.6. There is an on-site apparent irrigation well that is defunct and capped with a welded lid. The proposed well for the project development should be sampled after development for the EHD analytical requirements when it becomes operational. Calculation of Alkalinity Requirement for Nitrification The nitrate-nitrogen loading calculation results are contingent upon the environmental factors required for nitrification to occur. These conditions include soil pore-space oxygen content, soil temperature,pH, electrical conductivity, organic matter, cation exchange capacity, and alkalinity. Alkalinity in wastewater effluent is derived from the future on-site well water, in addition to the introduction of wastes in the effluent. As referenced,however, the well cannot be sampled due to the welded lid. E. SURFACE WATER INFORMATION Storm water management will be by on-site retention. Percolating rainwater from the retention basin may theoretically provide a water table dilution effect in the winter months to the water table nitrate concentrations. A scientific paper authored by Shaw and Turyk(1994) found that reduction of nitrate concentrations in groundwater can occur primarily through dispersion, by percolating rainwater, or a cleaner water source including effluent water recharge. NLS§3.2. The design of the wastewater management system for the mitigation of nitrate loading will take advantage of evapotranspiration and the uptake of effluent nitrogen through grass/lawn area planted over the disposal field. This design concept is further.discussed in Section IV. i 4 Chesney Consulting