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rA water table depth of 4.5 feet would preclude the installation of a conventional, or semi- conventional leachfield system. This is due to the required separation distance of five feet that must be maintained between the soil-effluent interface and the highest depth to the groundwater ! table. This is discussed in the "Mounding Analysis" Section of this Report. A second critical issue regarding the groundwater elevation in combination with the five-foot separation distance, is that the water table cannot encroach up to the septic tanks, which may cause buoyanc NLS§2.x,3.3,SSS§2.1,4.2. S- ce surrounding pro ies have been intensely farmed for several decades, the potential for nitrate ion in the underlying groundwater is significant. In addition, it appears that poultry was raised on the subject property, thereby affecting the soil, and particularly the groundwater water table with high nitrate concentrations. Groundwater research in the scientific literature suggests there may be a large denitrification potential within aquifers or I saturated zones composed of a fine silty clay soil fraction. So the observed nitrate concentration may be a7ally higher if this potential did not occur. � C NLS§2.3,SSS§4 3,4.4,4.5. As referenced,the on-site domestic well was sampled for analysis. This sample was obtained from a hose Bibb on the east side of the pump house. The pump was allowed to:'run for 30 minutes to ensure that aquifer formation water was sampled and not stagnant well casing or tank water. A water table sample was also retrieved after the backhoe test pit excavation. A one-half liter plastic bottle was used for both water samples. The two sample containers were placed in a cooled ice chest and then transported to A&L Western Agricultural Labs in Modesto, under the attached Chain!of Custodies on the respective days. The constituents tested were for nitrate, total alkalinity and chloride. Medium-to-high groundwater chloride concentrations may indicate contamination from septic system effluent, since human wastes are generally high in chloride content. Chlorides travel exceptionally well in the soil environment, even better than nitrate,and can be an excellent indicator of septic effluent pollution. The aquifer well water reveals low concentrations of all the constituents tested; however, the water table sample reveals high concentrations of the tested constituents, as illustrated in the following Tables: TABLE 4 ON-S1TE LWELL WATER ANALYSIS ANALYTE kfVEL UND MAXIMUM CONTAMINANT LEVEL(MCL) Nitrate 7 m 45 mg/L(ppm) Chloride 55 mg/L 500 mg/L . I Total AlkalinityT_ 121 mg/L No Standard TABLE 5 WATER"NABL•E ANALYSIS ANALYTE E OUND MAXIMUM CONTAMINANT LEVEL(MCL) Nitrate ` 97m L 45 mg/L(ppm) Chloride 332 mg/L 500 mg/L, Total Alkalinity 540 mg/L No Standard 7 Chesney Cons loping