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f 06/29/2006 13:49 FAX ^ 10 010027 RD Our calculation that includes both the proposed temple and the existing home is as follows: Nc = ..... x:76.(45)(1..=0.2) L L9,2)(0.5) _` ,7 rrt. # as N (2.76 + 9.2) Given the above factors, we estimate that the facility would require an average waste/sewage flow over 10,200 gal./week in order to exceed the state drinking water standard for nitrogen (N) of 10 mg/1 in groundwater_ We have also used the Hantzsche mass balance equation (source: Predicting Groundwater Nitrate-Nitrogen Impacts, Hantzsche and Finnemore (1992)), which is presented below, to help predict the nitrate loading taking into consideration a square mile of development around the proposed Sikh Temple. N� + .(N�s) R I - f Nw 1-D + I (l �,} AW#�W (�.Y �. ....-.......... .............. (I+R) AW + R Where: Nc = Average calculated nitrate-nitrogen in groundwater resulting from leach field source and precipitation - mg/l, as N. I - Volume rate of waste water from the proposed Sikh Temple entering the soil averaged over the gross developed Sikh Temple area = 2.76 Inches per year (calculated as follows: (8.400 gal/week x 52 weeks/year Q:1337 cubic ft/gal)/(5,8-3 acres x 43,560 sq ftlacre) x 12 inches/ ft)) NW Nitrate concentration of nitrified leach-field effluent (mg/1) = 45 mgll (The Hantzsche and Finnemore (1982) technical paper indicates that the average total nitrogen concentration in septic tank effluent ranges form 35 to 45 mg/l, This range was also reported in the 1996 Dames and Moore technical memorandum. Accordingly, our assumed value is considered conservative.) D Fraction of nitrate-nitrogen loss due to dentrification of leach field effluenit = 0.2 percent (Per Hantzsche and Finnemore (1992), 0.10 to 0-35 is typical). The 0.2 value was selected given that groundwater in the project area is relatively shallow and the subsurface soils are fine grained and will not easily allow infiltration of effluent to the groundwater R - Average recharge rate of rainfall = 9.2 inches per year (representing 30 percent of the average annual rainfall of approximately 11.5 inches. The remaining 20 percent of rainfall is assumed to drain oft:-site into natural or manmade drainages or be lost to evapotranspiration.) 71324.0011STO5R691 iinr Jsl.7.i}7fi Copyripht n00-55 Kloinfolder.inc. Page G^`ft