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The average total nitrogen concentration of domestic wastewater is about 20-85mg/L-N, although 35-45mg/L-N is a better approximation(Crites and Tchnobanglous). The value selected for this site was 35mg/L-N assuming this site shall experience a larger concentration. 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(Ni)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 moderate levels of denitrification. It is expected that a site with soil of these characteristics shall have approximately about 10-15% of denitrification. The value used for this site was 15%. 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 this 4.38-acre site would contain a Nitrate Load (Nc) of 8.80 mg/L-N when the site is generating its peak flows. 6.0 Discussion of nitrate loading results relative to proposed method of wastewater disposal 6.1 Discussion of total nitrate impact from proposed project: There are possibilities that the percolating effluent could affect water conditions. The Hanztch/Finnemore equation added to the County's factor of safety of two diminish those risks, but no major additions should be made beyond the proposed improvements mentioned previously without an update to this report. 6.2 Description of the methods proposed to mitigate any known or future impact to soil and groundwater from nitrate and/or other constituents of concern,at and/or around the project site: The project, as described in this report is sustainable by the site in current conditions. Additions or modifications to the site may require the addition of a waste water treatment system. At the time an addition is proposed, this report should be updated to ensure the adequate improvements are made. 7.0 CONCLUSION AND RECOMMENDATIONS SECTION The conclusions of this report are based on the information provided regarding the proposed development,the use of the subject property,and the site conditions as they existed at the time,we excavated our test hole and performed the percolation test. It was assumed that the test hole and percolation test and the compiled data results are representative of the subsurface conditions in the general area. The site complies with the San Joaquin County requirement by having a project site with less than 10.0 mg/L-N. The values used for calculations assume that the nitrate concentration of rainfall is 1 mg/L-N as previously noted (Hanztch/Finnermore). Also, the site contains denitrification processes and that based on uses the site effluent stream is 35 mg/L-N. Analyzing all the compiled data,the site is adequate for the proposed use. 1' 6