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This can be attributed to the lack of a dilution effect that graywater from showers,laundry,and dishwashing would provide from a household. The scientific literature cites nitrogen concentrations in residential septic effluent typically ranging from 17 mg N/L for basins,sinks, etc. to 140 mg N/L for toilet wastes. Therefore, considering a 70/30 percent usage for toilet water volume and sink water volume,respectively,a value of 103 mg N/L of septic effluent will be used to calculate nitrate-nitrogen loading for this project. A value of 66 mg N/L is typically used for residential calculations,as indicated in the scientific literature. B. CALCULATED NITRATE-NITROGEN LOADING The calculated nitrate-nitrogen impact to the soil and ultimately to the groundwater is difficult to determine due to the large number of variables involved and variables unknown at this time. These include: 1.)Impact from upgradient nitrate sources,2.)Variability in wastewater flows,nitrogen concentrations and dilution effects from effluent and stormwater recharge, 3.)Changes in groundwater directional flow and elevation,4.) Denitrification potential within the soil environment and within the confined and unconfined aquifers and 5.) Potential landscape uptake of nitrogen,and most importantly,a cleansing effect by the San Joaquin River. Various scientific methods exist to estimate nitrate-nitrogen loading. This Study will use the Hantzsche/ Finnemore Formula to predict the average resultant concentration of nitrate-nitrogen in effluent recharge water. As calculated below,the property has been assessed on a total areal loading basis of 30 acres for the entire APN exclusively,correlated with 84 gallons ADFper day from both restrooms, as noted above(a men's and a women's toilet in the modular building). These two factors primarily dictate the average resultant concentration of nitrate-nitrogen in the recharge water,which cannot exceed 10 ppm nitrate-nitrogen(45 ppm as nitrate). The following calculations demonstrate the resultant effluent recharge water from the project will not exceed the Maximum Contaminant at Level(MCL). NLS 3.4,3.5,3.6 PREDICTED NITRATE-NITROGEN LOADING FROM THE HARVEST POWER COMPOSTING FACILITY USING THE MAXIMUM AVERAGE DAILY FLOW(ADF) OF 84 GALLONS PER DAY FOR THE NEW MODULAR BUILDING,AND TAKING THE PROJECT AREA OF 31 ACRES INTO CONSIDERATION: HANTZSCHEIFINNEMORE EQUATION IN(1 -d)+RN Nr (I+R) Where: Nr= Resultant average concentration of nitrate-nitrogen in recharge water-(ppm NO3-N) I = Volume rate of wastewater entering the soil averaged over the gross developed area in inches per yr Nw= Total nitrogen concentration of wastewater in nt g R x ) d = Fraction(%)of nitrate-nitrogen loss due to denitrification'in the soil R = Average recharge rate of rainfall- inches per yr NLS§3.2 Nb= Background nitrate-nitrogen concentration'Of rainfall recharge,exclusive of wastewater influences (PPM NO3-N) Values and Assumptions: I= 84 ¢pd x 365 d/yr=30.660 gals=total WW/yr=5.000 cu ft = 0.036 in. 31 Ac x 43,560 sq ft/Ac x(I ft/12 in.) 7