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FI [ <br /> April 29, 2005 - <br /> NOA Project Number: E05040A <br /> FJThe following discussion is for determining the long-term waste watei.flow generated from the <br /> proposed residences for the nitrate loading analysis and should not be used for septic system design <br /> purposes. Typically,use estimates for the sizing of septic systems include a peak use factor,whereas <br /> the numbers discussed here are based on long-term averages." <br /> A four bedroom home is present on Parcel 14. The four bedroom home is presumed to be occupied <br /> F, by up to five people over the long term.A second dwelling unit, occupied by a potential three <br /> people, could be placed on the parcel as well. Therefore, a total of eight people per parcel will be <br /> used to calculate the residential septic tank usage for parcel 14. <br /> For Parcels 8-13 and 15 -20 it is likely that a three to five bedroom <br /> home will be built For this <br /> calculation a five bedroom home will be used.A five bedroom home is presumed to be occupied by <br /> up to six people over the long term. A second dwelling unit, occupied by a potential three people, <br /> could be placed on the lot as well. Therefore, a total of nine people per parcel will be used to <br /> calculate the residential septic tank usage for the parcels. <br /> k <br /> The estimated sewage flow rates for use categories are available from a number of references. The <br /> uses presented below were guided by the San Joaquin County On-Site Wastewater Disposal Standards <br /> F1 (2003), Crites and Tchobanoglous (1998), and EPA (1980). The text from Crites and Tchobanoglous <br /> — (1998) (Table 4-2) indicates that the typical residential use rate is 70 gallons per day. The EPA <br /> F <br /> (1980) Design Manual (Table.4=6) indicates the typical use rate is 45 gallons per day for a resident. <br /> The following tables presents the septic waste water uses associated with the Site. The rates_ <br />' presented from the references provide general guidance but do not always reflect a match in usage. <br /> Careful examination,professional judgement, and experience are necessary to select a reasonable <br /> flow rate estimate. The flow rates selected for the uses associated with this project are presented in <br /> the following table. <br /> Table 1. <br /> FIT ical Quanti of Effluent for Parcels 8-20. <br /> Category Total People per Average Quantity per Average Daily Flow <br /> F1 <br /> Day Person Per Parcel <br /> Residential <br /> (Parcel 8-13 and 9 70 gal/day/resident 9 residents*70 gpd/resident <br /> 15-20) = 630 gpd <br /> Residential 8 residents*70 gpd/resident <br /> arcel 14 $ 70 gal/day/resident = 560 d <br /> 1 ; Note —gpd is gallons per day. <br /> For Parcels 8-13 and 15-20, the total daily waste water quantity is 630 gallons per day. For Parcel 14, <br /> the total daily waste water quantity is 560 gallons per day. <br /> The average total nitrogen concentration of domestic waste water is normally considered to-be <br /> 20-85 mg/L-N (Crites and Tchobanoglous, 1998). For the purposes of the nitrate loading estimate, <br /> 4 <br />