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The results for the deep percolation at the site were 6.93 in./year for the 1.53 acre parcel. 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 sources of nitrates are the existing septic system in use by an existing parcel for residential uses. The existing septic system was accounted for when determining the approximate nitrate concentration. The site is expected to see an increase in its current flow 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 future use of the site will remain consistent. The existing residence with 3 bedrooms was used to approximate the amount of people that could generate wastewater flow. It was conservatively assumed that 100 gal/day would be generated for the first bedroom and 50 gal/day subsequently for every other room, generating at a total of 200 gallons/day. The site is expected to be able to handle up to 300 gallons/day, making the current and proposed flows sustainable. There is a residence on the 1.53 acre parcel, 200 gallons/day were used for the three bedroom house. The proposed guest house would add another 100 gallons/day of flow. The 1.53 acre parcel should have no problem with the 300 gallon/day total of flows, but 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 40mg/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 20-30% of denitrification. The value used for this site was 30%. 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 1.53 acre parcel would contain a Nitrate Load (Nc) of 9.99 mg/L-N when the site is generating its peak flows. 3