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The data for the potential evapotranspiration water was obtained from the California Irrigation Management Information System (CIMIS). The project is located within an area designated as Zone 12. Based on the values for this area along with the average monthly precipitation values obtained from the Western Regional Climate Center for the region, an estimate of the deep percolation of rain for the project was determined. Station 70 in Manteca had the most similar weather and soil conditions to our project site. The results for the average rainfall recharge at the site were 4.20 in./year. The nitrate concentration is estimated to be about 1 mg/L-N. (Hantzche and Finnemore, 1992). 5.3 Description of all current on-site sources of nitrate to soil and groundwater and the contribution of nitrate load from these sources to the project site: The only source of nitrates are the existing septic systems in use by the existing parcels for residential uses. The existing septic systems were considered for when determining the approximate nitrate concentration, the site could expect with the proposed development. 5.4 Discussion of all proposed future on-site sources of nitrate to soil and groundwater and the contribution of nitrate load from these sources to the project site: The existing use for this site is residential. It is assumed that every residential home will generate 100 gal/day of waste for their first bedroom and 50 gal/day for each subsequent bedroom. Proposed Parcel 1 currently has a 4 bedroom residence on it. Assume a new 2 bedroom secondary dwelling unit was constructed as well, this would bring the total waste generated to 400 gal/day on proposed Parcel 1. Proposed Parcel 2 currently has a 3 bedroom residence on it generating 200 gal/day on proposed Parcel 2. The project site would generate 60_0_ga_ 1�y of waste which can be sustained as shown on the included calculations. The average total nitrogen concentration of domestic wastewater is about 20-85 mg/L-N, although 35-45 mg/L-N is a better approximation(Crites and Tchnobanglous). The value selected for this site was 45 mg/L-N. The site will experience a process of denitrification as the soil naturally treats surface material through natural forms. Denitrification is a process that occurs when bacteria uses oxygen in the nitrate(NO3) and release nitrogen(N2) into the atmosphere. Denitrification can be variable to the type of soils, chemical properties,moisture content and other variables. Based on the sandy loams on-site and the moderate percolation rates, this site's soil has moderate levels of denitrification. It is expected that a site with soil of these characteristics shall have approximately about 10-20% of denitrification. The value used for this site was 15%. 5.5 Calculate mass balance of nitrogen loading considering all potential sources identified using Hantzsche/Finnemore equation: Using the data mentioned within this report and the attached Soil Suitability Report the mass balance of nitrogen loading for this site was calculated, this was done using Hantzsche/Finnemore formula. Based on the Hantzsche/Finnemore equation Parcel 1 is a 9.99 acre site and would contain a Nitrate Load (Nc) of 5.23 mg/L-N. Parcel 2 is a 2.01 acre site and would contain a Nitrate Load (Nc) of 9.98 mg/L-N. TRe g�y flow would avoid the site's nitrate load from surpassing the maximum containment level (MCL) of 10.0 mg/L-N for Nitrate in drinking water. 3