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r7I7= 53.5 inches/yr x 27,152 gals/ac-in x 875 sf filter bed(0.0201 ac)=29,198 gals/yr. E=Effluent disposal volume for the proposed modular home was originally calculated by Petralogix to be 140 gpd per each bedroom for a total ADF of 560 gals. Their subsequent Addendum revised the ADF to 250 gpd,based on the arbitrary decision of the previous EHD Director to assign 100 gallons for the first bedroom and 50 gallons for each additional bedroom. E= 250 gals ADF x 365 dpy=91,250 gals/yr ETo=The yearly actual evapotranspiration(ETo) illustrated in Petralogix Report total 52.42 in/yr: 52.42 inches/yr x 27,152 gals/ac-in x 875 sf filter bed(0.0201 ac)=28,609 gals/yr. From the water volume data presented, it appears that the effluent water volume may supply the lawn grass irrigation demand. ETo theoretically cancels almost 100%of domestic irrigation demand. However, supplemental lawn irrigation will be needed since the effluent disposal volume is heavily inflated due to assigning the ADF of 250 gpd to every day of any given year. NITROGEN DEMAND FOR FESCUE LAWN GRASS The lawn grass uptake of effluent nitrogen is determined as follows: The EHD directive references the Regional Water Quality Control Board 2012 OWTS Policy, as stated, is"to meet a 50%reduction in total nitrogen when comparing the 30-day average influent to the 30-day average effluent." The Petralogix Report nitrate loading calculations demonstrate a Resultant(NR) average concentration of nitrate-nitrogen in recharge water of 13.53 ppm from the proposed primary unit dwelling. Total nitrogen concentration of raw wastewater was identified at 35 mg/L in the Petralogix Report. Although Petralogix references this concentration as (NW) =Total nitrate-N concentration of wastewater percolate;this is not the N concentration of the percolate. NW should be referenced as the raw wastewater N concentration. Complying with the 50%reduction in nitrogen concentrations between the raw wastewater influent and treated effluent, places the effluent concentration requirement after the proposed vegetative treatment at no greater than 35 mg/L x 50%= 17.5 mg N/L. According to The International Plant Nutrition Institute,which is now part of The Fertilizer Institute, 0.675 tons of Fescue grass removes 25 lbs of nitrogen per ton of Fescue removed. The following calculations demonstrate that the Fescue lawn grass can theoretically uptake the effluent nitrogen to lower the effluent concentration from 35 mg N/L(raw wastewater N concentration)to 17.5 mg N/L (max. effluent N concentration): 0.1 lbs Fescue grass/sf x 875 sf filter bed= 87.5 pounds grass/cutting. 2 cuttings per month over eight month growing.season(Feb-Oct)= 18 cuttings 87.5 lbs. grass/cutting x 18 cuttings= 1,575 lbs grass (0.788 tons=29.2 lbs N removed) However, 35 mg/L of total nitrogen in the raw wastewater equates to 0.000291756 pounds of nitrogen per gallon of influent. The total volume of raw wastewater flow from the primary Pae -3- Chesney Consultin,