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06/29/2006 13:50 FAX C-11 [�011/027 Nt = Background nitrate nitrogen concentration of rainfall recharge at the vrater table = 0.5 mgli (per Technical Memorandum, Hydrologic and Soil Investigation for the Chico Urban Area, page 6, Dames.and Moore, April 1096) A - Number of dwelling units per acres on septic tanks within a square mile around the proposed Sikh Temple (unitlacre) = 0.17 (estimated based on 54 lots, assuming 2 horses per lot (108 homes total), divided by (640 acres - 5.83 acres)) W = Annual wastewater loading per dwelling unit per acre (inches) = 0.68 inches (based on 300 gpd/residence) Our calculation that includes both the proposed temple, the. existing home, and considering a square mile around the site is as follows: Ne .:is 5).��. �.:.��..+ �? .......... + _..... _ ?( .ss)t 5... 1 o.z�}..� 1.._` : ....._.._ = 9.64 mg4 w N f - (2.76+9.2) (0.17)(0.68) +9,2 Given the above factors, we estimate that the proposed Sikh Temple would requir-< an average wastelsewage flow of 8850 gal,tweex in order to exceed the state drinking water standard for nitrogen (N)of 10 mgll in groundwater. 10. CONCLUSIONS T ditof our percolation tests indicate that a suitable soil percolation stratum does Exist�' t the percolation test location at the SJCEHa approved depth tested of a or t-3 feet below existing site grade. A test was not performed in a deeper stratum due to the presence of groundwater st approximately 7 feet and the 10,foot separation requirement between groundwater and the bottom of percolation tests greater than 42 inoses. A suitable soil condition is defined as a stratum capable of percolating water atia rate of 60 min/inch or faster at shallow depths and 30 minlinch for deep tests. As previously mentioned, there was not a concentration of l7BCP found in the groundwater in detectable amounts. $ The concentration of nitrate-nitrogen (N) in the groundwater was above the state standard of 10 mg/l, Based on these results and the results of our nitrate loading Calculations, we estimate that the potential nitrate-nitrogen concentration in groundwater, resulting from both the e�istipq,,and new leach fields, will stay above the state standard of 10 mg/I. The Mokelurline l ver is the nearest water body to the sike and is located approximately 2"/a miles west of the property. Due to the distance: to the Mokelumne River and the general gradient of groundwater, we anticipate that the impact to surface water will be low. Based on the high concentration of nitrate- ?3374.<'01ISTMRsit11 June 2�%2006 Copyright 2000 KIdnicldcr,{rc. Paayc 'Y of E M