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The results for the deep percolation at the site were 6.42 in./year for the 26.38 acre parcel. The waste loading of the site is estimated at 1.78 in/year. The nitrate concentration is estimated to be about 1 mg/L-N for the rain concentration. (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 site has been vacant for over 30 years. There are no current on-site sources of nitrates. 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 future use of the site would change from its vacant status to an active truck facility. Accounting for 10 gal/person per day, based off the expected 20 employees, the expected flow of 200 gal/day were used for the site. The 26.38 acre parcel would not have a problem with these flows, considering peak flow rate allowed is 3500 gal/day. No major additions should be made without update to this report. 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 45mg/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 (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 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 Study, 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 26.38 acre parcel would contain a Nitrate Load (Nc) of 9.09 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 is a low possibility that the percolating effluent could affect water conditions. The Nitrate Load calculated in this report is within the acceptable range of San Joaquin County Standards. 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. All septic systems and leach fields must be constructed to San Joaquin County Standards and must be inspected by a County Inspector. 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.