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Total Nitrogenis-the summation of ammonia-nitrogen (NH,)and organic nitrogen (proteins;amino acids- enzymes). Since the septic tank is predominately anaerobic,_nitrogen cannot�exist in its-oxidized state as nitrate for any length of time in-the septic tank effluent, and if it does,-it is quickly reduced to NO or NO2. If nitrate existed in septic tank effluent,this would also be added,to ammonium and organic nitrogen to arrive at Total:Nitrogen: Not all of the Total Nitrogen analytically determined will be ultimately converted into f nitrate. The percentage is indeterminable due to numerous factors. Additional wastewater constituents may consist of coffee;juices or other similar type liquids to the system. It is imperative:that no industrial or commercial chemicals, solvents, excessive cleaners,etc. are introduced into the.septic system, as well as..other items such as sanitary napkins, any paperproducts other than toilet paper, cloth, plastic,cigarettes; etc. It is also imperative that no garbage disposals are installed. This will /prevent concentrated organic loading and prolong the lifespan of the wastewater disposal system. NLS§3.3. To quantify the anticipated nitrogen concentration for use in thenitrate.loading calculations, influent samples were obtained from three sequential on-site septic tanks. The first tank sampled was the lift station tank receiving influent from the Dry GoodsBuilding. Influent from this tank is pumped to a two compartment septic-tank on top of the mound system.-The second compartment of this septic tank was then sampled. The-third_tank sampledwas the dosing tank immediately after the-septic tank and before the i effluent gravity flows into the mound soil. The following Table summarizes.the analytical test results of influent.from the referenced three tanks. The scientific literature typically-assigns 70-90%of the Total Nitrogen.in septic tank effluent to be in the form of ammonium, while 10 to 30% is in the organic form. The percentages next to the Ammon ia=Nitrogen and Organic Nitrogen.concentrations indicate the percent these constituents comprise Total Nitrogen. In addition, concentrations of weak;medium and strong strength wastewaters have also.been presented for comparison purposes from Wastewater Engineering, 3'd Ed., in the three columns on.the right. TABLE 7 TANK FACATFON < �^ t a X 6Dry Goods Septic-Tank DOM ng - ` ewater Engineering Wast x Metcalf&Eddy 3'"Ed Bnild>ng Lift. j Sec©nd Tank ANALYTE F !' ationi (ConcentrsrimglL sStationTank ' _ .Co>Irepartment� I �- =Weak ;,Medi m =e Strong Ammonia Nitrogen(NHa N) 254 mg/L-(89%) 136 mg/L(80%) 113 mg/L(87%) 12 25 50 Organic Nitrogen 33 mg/L.(1.1V.) 34 mg/L(20%). 17 mg/L(13%) 8 IS 35 Total Kieldahl Nitrogen: 287 mg/L 170 mg/L.- _ 130 mg/L 20 40 85 Total Suspended Solids 180 mg/L ,372 mg/L 68 mg/L 100 220 .350 (TSS) Biochemical Oxygen .395 mg/L - -267 mg/L 164 mg/L 110 220 400 Demand(BODS) - Total Alkalinity 1080 mg/L 683 mg/L 585 mg/L 50 1.00 200 As noted, the TKN nitrogen concentrations in the effluent decrease in.each subsequent tank from 287 mg/L in the Lift Station to 130 mg/L in the Dosing Tank; a 55%decrease in nitrogen concentration. These analyses confirm the scientific premise that significant nitrogen decomposition occurs in septic tanks. In addition,the strength of the domestic effluent from the Winery can be classified as a strong wastewater. This may be due io a lack of a dilution effect that would normally be observed in household wastewater analysis from.showers, laundry, sinks, etc. 16 Chesney Consulting