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r 0136 (conversion factor for tons/Ac ft of water) = 82 lbs of NO3/Ac ft of water. If an average of 750 lons of domestic irrigation water is used each day for six months= 180 days x 750 gals/day5,000 gals(roughly '/2 ac-ft of water). 82 lbs NO3 x 0.5 =41 lbs NO3 applied by '/z ac-ft of domestic irrigation water. Kentucky blue grass requires 124 lbs N/ac/yr, or if 1/3 of a parcel is planted in blue grass=42 lbs N/'/s ac/yr for optimum growth. Therefore %2 ac-ft of domestic irrigation at 30 ppM NO supplies 100% of the nitrogen required by. this ,grass. C. WASTEWATER FLOW CALCULATIONS AND CHARACTERISTICS Domestic wastewater flows managed by on-site septic systems have been studied for decades with variable data published in the scientific literature. Wastewater flows for this project will be assessed on a near-future basis. It is proposed that the new house will be for Mr. and Mrs. Rinauro exclusively. The modular home will be for Mr. and Mrs. Rinauro's daughter and her son. It will be assumed future households will also have two persons per house since both structures will have only two bedrooms. The total daily water use is a combination of household and personal uses, as itemized below: HOUSEHOLD PERSONAL USE 25 gal for laundry 2 gal for drinking and cooking 10 gal for dishwashing 3 gal for oral hygiene 5 gal for misc. use 14 gal for bathing 16 gal for toilet flushing/sink washing FLOW RATE in gals/home/day= 40 gals/household/day+(35 gal/person/day x number of persons/home). The daily wastewater flow rate can be estimated at: 40 gals -+- (35 gals x 2 people/home) = 110 gals/day for an average flow per resident of 28 gals x 2 houses= 220 gals/day and an average flow per resident of 56 gals. The peaking factor for individual residences on septic tanks will vary with the day of the week and usage. Peak hourly rates are normally associated with the discharge of clothes wash machines, dishwashers and shower/bath water. The ratio of the peak day to the average day can vary from 1.5 to>5, depending upon the time of the year and usage. The characteristics or composition of septic tank effluent is dependent upon several parameters because of idiosyncrasies within each household. Certain appurtenances change the characteristics of the wastewater effluent such as filter vaults within septic tanks and kitchen food-waste grinders. Since this study is concerned with nitrogen, this constituent is quantified in the effluent, as illustrated below: In determining nitrogen concentrations of septic influent and effluent, per capita intake of nitrogen per day must be estimated. The average American consumes between 70 and 140 g of N/day. Since nitrogen comprises 16% of the weight of the average protein, 16% of 70 g N = 11 g N/capita/day and 16% of 140 g N= 22 g N/capita/day. The average of these two values is 17 g N/capita/day of theoretical influent. Page -5- C&sney Consulting