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#_ ,} R:1 KLEINFELDER Nb - Background nitrate nitrogen concentration of rainfall recharge at the water table = 0.5 mgll (per Technical Memorandum, Hydrologic and Soil Investigation for the Chico Urban Area, page 6, Dames and Moore, April 1996) t Our calculation that includes both the proposed temple and the existing home is as follows: __ 2.76(45)(1-0.2) + 9.2 0.5 N� (2.76 + 9.2) = 8.7 mg/1 as N ° Given the above factors, we estimate that the facilitywould require an average waste/sewage flow over 10,200 gal./week in order to exceed the state drinking water s standard for nitrogen (N) of 10 mgll 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. _ _ I(Nw)(1-D) + R(Nb) + AWN, (1-D) + Ne R Nc (I+R) AW + R Where: F. Nc = Average calculated nitrate-nitrogen in groundwater resulting from leach field source and precipitation - mg/l, as N. I 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 gallweek x 52 weeks/year x 0.1337 cubic fugal)/(5.83 acres x 43,560 sq ft/acre) x 12 inches/ft)) 1 N,, = Nitrate concentration of nitrified leach-field effluent (mg/1) = 45 mg/l (The Hantzsche and Finnemore (1992) 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 effluent = 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 71324.GO1/ST06R648 June 19,2006 ©2006 Kleinfelder, Inc. Page 6 of 8