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S 55 ✓L NLS§ 2.2,3.1, SSS§2.1,4.2. Since surrounding properties have been intensely farmed for several decades, the potential for nitrate contamination in the underlying shallow groundwater �J ( J '� aquifers is significant. Well water obtained for analyses from the on-site well indicate non-detect Z� CZ DBCP and a nitrate concentration of 0.5 mg/L. These non-existent/extremely low concentrations may be attributed to the 290 ft deep well, sufficient intervening clay layers attenuating the downward migration of nitrate and DBCP, and sufficient denitrification potential within the underlying aquifers, as referenced above. CZ a, NLS§2.3,SSS§4.3,4.4,4.5. On March 11, 2014, the siteas sampled by FGL Environmental Laboratories. Sampling procedures er the correct protocol including cycling the pump to sample aquifer water and not stagnant well water. Well water was sampled from a sampling port on top of the discharge pipe from the well casing. The attached Chain of Custody illustrates all pertinent data. 'G� The sample bottles were placed in a cooled ice chest after sampling, and then transported to FGL Environmental Laboratory in Stockton. As referenced,the constituents tested were for nitrate and DBCP. The following Table summarizes the test results: TABLE 3 UNDERLYING GROUNDWATER ANALYSIS FROM THE ORIGINAL OLD WELL AND THE RECENTLY DRILLED NEW ON-SITE DOMESTIC WELL ANALYTE ON-SITE DOMESTIC WELL Nitrate(As nitrate) 0.5 mg/L DBCP ND Dibromochloropropane Non Detect Calculation of Alkalinity Requirement for Nitrification The nitrate-nitrogen loading calculations on Page 9 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 domestic well water supply in addition to the introduction of wastes. Nitrification consumes approximately 7.1 mg of alkalinity for every mg of ammonia-nitrogen (NH4-N) oxidized. Therefore,the low alkalinity concentration found in the regional groundwater may theoretically inhibit nitrification to an indeterminable degree. Mounding Analysis Since the static water table was measured at 28 feet from the sounding of the domestic well,adverse mounding potential should be nonexistent and inconsequential. Additionally, since a large percentage of sand is known to occur at the deeper depths,this would also in all likelihood, prevent the formation of the mound phenomenon under the disposal area. The critical issue regarding the groundwater elevation is: 1.) There must be sufficient distance between the soil/effluent interface and the highest anticipated depth to groundwater for sufficient treatment of effluent to occur,which is generally accepted to be five feet for ]each]ines/filter beds and 10 feet for sumps or seepage pits, and 2.)The water table cannot encroach upon the septic tanks,which may cause buoyancy. These two parameters are easily satisfied. C