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f <br /> B. CALCULATED NITRATE-NITROGEN LOADING <br /> NLS§ 3.3. The calculated or estimated nitrate-nitrogen impact to the soil and ultimately to the <br /> groundwater is difficult to determine due to the number of variables involved. These variables <br /> include: 1.) Variability in wastewater flows, nitrogen concentrations and dilution effects that may <br /> occur, 2.) Impact from previous on-site operations (the school and the labor camp), 3.) Upgradient <br /> nitrate sources from agricultural farmland, 4.) Changes in groundwater directional flow and elevation <br /> due to tidal action, 5.) Denitrification potential of the underlying soil, and 5.) Rainfall recharge. <br /> As noted in Table 6, the Total Nitrogen (TN) content is 89.4 ppm which will be used in the nitrate <br /> loading calculations, below. Various scientific methods are used to estimate nitrate-nitrogen loading. <br /> This study uses the Hantzsche/Finnemore Formula to predict the average concentration of nitrate- <br /> nitrogen in effluent recharge water. <br /> NLS§ 3.4,3.5,3.6. PREDICTED NITRATE-NITROGEN LOADING FROM THE LAND-SIDE AREA <br /> OF THE BULLFROG LANDING MARINA,ALONG WITH AND THE PROPOSED ADDITION OF <br /> THE FOOD PREPARATION/SERVICE BARI PATIO DINING AREA USING THE MAXIMUM <br /> �j AVERAGE DAILY FLOW (ADF) BASED ON THE PARAMETERS DESCRIBED ABOVE,AND <br /> TAKING THE PROJECT LAND-SIDE AREA OF 1.54 ACRES INTO CONSIDERATION: <br /> HANTZSCHEIFINNEMORE EQUATION <br /> INwl1 - d) + RNb <br /> Nr= (I+R) <br /> Where: <br /> Nr= Resultant average concentration of nitrate-nitrogen in recharge water-(ppm NO3-N) <br /> I = Volume rate of wastewater entering the soil averaged over the gross developed area in inches per yr <br /> Nw= Total nitrogen concentration of wastewater in mg NIL <br /> d = Fraction(%) of nitrate-nitrogen loss due to denitrification in the soil <br /> R = Average recharge rate of rainfall -inches per yr NLS§ 3.2 <br /> Nb= Background nitrate-nitrogen concentration of rainfall recharge, exclusive of wastewater influences <br /> (ppm NO3-N) <br /> Values and Assumptions <br /> 1= 375m d x 365"dl r= 136,875 gals=total WW/yr= 18,299 cu ft = 3.27 in. <br /> 1.54 Ac+ x 43,560 sq ft/Ac x(1 ft/12 in.) <br /> Nw =89.4 mg NIL: 20% N reduction occurring in the septic tank+ 10%reduction at the soil effluent interface <br /> = (1-0.3) x89.4=62.6 mgN/L ✓ <br /> de= fe <br /> 25%due to the peat nature of the native soil and therefore medium-high denitrification potential <br /> R Nh dto be 0.1 ppm NO3-N <br /> I1 <br /> Chesney Consulting <br /> C <br />