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r77NLS§2.2,3.1, SSS§2.1,4.2. Since the surrounding properties have been farmed for a number of decades,the potential for nitrate contamination to the underlying groundwater aquifers can be considered significant. However,this was not observed. NLS§2.3, SSS§4.3,4.4,4.5,4.6. Mr. Bowen's existing domestic well was sampled for analysis. The pump was run for 20 minutes before sampling, with the sample obtained from a hose bibb on the south side of Mr. Bowen's house. The Table below summarizes the test results obtained. TABLE 3 pb WELL ANALYTE CONCENTRATION MAXIMUM CONTAMINANT FOI JND LEVEL(MCL) Proposed Nitrate(As Nitrate) 15 ppm 45 ppm Parcel 1 Domestic Well Total Alkalinity 195 ppm N/A Sampled from Sampling Port on south well Dibromochloropropane Below Detectable Limits uio Et/L(ppb) discharge pipe. DBCP I (BDL) Calculation of Alkalinity Requirement for Nitrification The nitrate-nitrogen loading to the underlying groundwater is 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 well water, in addition to the introduction of wastes. Nitrification consumes approximately 7.1 mg of alkalinity for every mg of ammonia-nitrogen(NH,-N) oxidized. Nitrification of the average Total Nitrogen(TN) concentration of 62 mg/L, as determined on Page 7, would require: 62 mg/L NH4-N x 7.1 mg CaCO3 =440 mg/L alkalinity. The alkalinity concentration in the Parcel 1 well water was determined to be 195 ppm. Therefore, there is an insufficient alkalinity in the well water for complete nitrification to readily proceed without the introduction of wastes and the alkalinity within the soil environment. E. SURFACE WATER INFORMATION Storm water management will be by on-site retention. Percolating rainwater will theoretically provide an indeterminable water table dilution effect to percolating wastewater effluent. However, as referenced in the next Section, rainfall in comparison to evapotranspiration is minimal. Climatic Data: Rainfall versus Evapotranspiration NLS§3.2. It is generally and scientifically accepted that when precipitation exceeds evapotranspiration(Eto), deep percolation of surface rainwater may occur. Evapotranspiration refers to water evaporation that takes place both at the soil surface and transpiration by plants. Page-5- Chesney Consulting