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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 stem from the existing septic system in use by an existing parcel for industrial uses. The existing septic system was 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 industrial. The proposed site expects to have 40-45 employees. Assuming 45 employees from 6:00 am— 8:00 pm and that an industrial site would generate 25 gals/person/day when a cafeteria is provided. The expected value of generated liquid waste is 609.4 gals/day. This project site can sustain this flow 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 35 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. Denitrification is an important process which occurs with the leach field whereby certain bacteria utilize the oxygen in the nitrate(NO3) and release nitrogen gas (N2) to the atmosphere. Denitrification is expressed as a percentage, and the normally accepted range is 10 percent to 35 percent. Soils with higher clay content, moist soil conditions, high pH, and organic material denitrify by about 35 percent, and soils with high sand content and fast percolation rates are estimated to denitrify at a lower rate, about 10 percent to 15 percent. A denitrification factor of 25 percent was used for the Site. 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 19.93 acre site would contain a Nitrate Load (Nc) of 2.29 mg/L-N. The maximum volume the site can handle is approximately 3600 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.