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Nitrate is not found in septic system effluent due to anaerobic conditions within the tank7the <br /> therefore not included with the TKN to arrive at TN. This TKN concentration will be u <br /> loading calculations below. The following Table summarizes the septic tank effluent analytical test <br /> results: <br /> TABLE 5 <br /> SEPTIC TANK EFFLUENT SAMPLED FROM TANK INSTALLED IN 2017 SERVING <br /> THE HOLLY COMMERCE CENTER: <br /> ANALYTICAL RESULTS OF TESTED CONSTITUENTS <br /> SAMPLE ID AMMONIUM ORGANIC NITROGEN TOTAL KJELDAHL pH <br /> NITROGEN-NH, NITROGEN(ThN) <br /> Holly-S.T. EFF. 137 mg/L 9 mg/L 146 mg/L 6.5 <br /> B. CALCULATED NITRATE-NITROGEN LOADING <br /> NLS§3.4,3.5,3.6. The calculated nitrate-nitrogen impact to the soil and ultimately to the groundwater <br /> is difficult to determine due to the large number of variables involved and variables unknown at this <br /> time. These include: 1.) Impact from upgradient nitrate sources, particularly the City of Tracy <br /> Wastewater Treatment Plant, 2.) Variability in wastewater flows, effluent nitrogen concentrations and <br /> dilution effects from Sugar Cut and stormwater recharge, 3.) Changes in groundwater directional flow <br /> and elevation caused by surrounding water bodies, and 4.) Of significant importance is not only the <br /> denitrification potential of the indigenous clays, but equally important is the diminished nitrification <br /> potential within the clay soil environment along with the lack of sufficient alkalinity. The extremely <br /> small pore space within the high clay content-soil significantly reduces oxygen content,thus impeding <br /> nitrification. <br /> Although there are a number of formulas and equations to predict the inexact science of nitrate impact <br /> potential from septic systems,the Hantzsche/Finnemore Equation is used below to calculate the average <br /> concentration of nitrate-nitrogen in effluent recharge water from the proposed septic system. The <br /> calculations are based on the combined area of the footprint of the two Buildings for a total of 10 acres. <br /> This is discussed further in the Conclusions Section. The annually projected wastewater flows of <br /> 156,000 gallons/yr is derived as follows: (640 gpd x 5 dpw=3,200 gpw x 52 wpy= 166,400 gpy). <br /> These two factors primarily estimate the average resultant concentration of nitrate-nitrogen in the <br /> recharge effluent. This concentration shall not exceed 10 ppm nitrate-nitrogen(45 ppm as nitrate). <br /> HANTZSCHEIFINNEMORE EQUATION <br /> INW(1 - d)+RNh <br /> Nr= (I+R) <br /> Page -7- <br /> Chesney Consulting <br />