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The data for the potential evotranspiration 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 Lodi 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 deep percolation at the site were 2.65 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 originate from neighboring sites of residential and agriculture use. The site was formerly used as a dairy. There are no records of any septic system within 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 proposed use for this site will be residential for up fifty-four 1 acre lots and a 5 acre Designated Remainder parcel. It is unknown how many room or fixtures will be in the built on these lots, so an average was determined. For residential use, the approximate flow rate that is expected to be used is between 50 to 70 gallons per person per day (Crites and Tchobanoglous). As this method of determining nitrate loads is conservative on its own,the value of 70 gallons per person per day was used. This method is conservative as it does not include lateral dispersion or mixing of groundwater. The residential homes are expected to be between 3 and 4 bedrooms, so an average of 4 was used for a total of 280 gallons per day. The average total nitrogen concentration of domestic waste water is about 20-85 mg/L-N (Crites and Tchnobanglous). The value selected for this site was 20 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 high percolation rates,this site's soil has low levels of denitrification. It is expected that a site with soil of these characteristics shall have approximately about 10-25% of denitrification. The value used for this site was 19%. 5.5 Calculate mass balance of nitrogen loading considering all potential sources identified using Hanztch/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 Hanztch/Finnemore formula. Based on the Hanztch/Finnemore equation each one-acre site would contain a Nitrate Load(Nc)of 9.92 mg/L-N. The site can handle approximately 280 gal/day,a flow surpassing that amount could cause an impact to the site's nitrate load and surpass the maximum contaminant level (MCL) of 10.0 mg/L-N for Nitrate in drinking water for lots of one acre. Lots larger than one-acre have more flexibility, although flows exceeding 280gal/day should be evaluated on a case by case basis. 3