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The results for the deep percolation at the site were 5.98 in./year for the 2.00 acre parcel. The <br />nitrate concentration is estimated to be about 1 mg/L-N for the rain concentration. <br />(Hantzche and Finnemore, 1992). <br />The results for the deep percolation at the site were 4.35 in./year for the 2.46 and the 2.69 acre <br />parcel. The nitrate concentration is estimated to be about 1 mg/L-N for the rain concentration. <br />(Hantzche and Finnemore, 1992). <br />5.3 Description of all current on-site sources of nitrate to soil and groundwater and the <br />contribution of nitrate load from these sources to the project site: The sources of nitrates are <br />the existing septic system in use by an existing parcel for residential uses. The existing septic <br />system was accounted for when determining the approximate nitrate concentration. The site is <br />expected to see an increase in its current flow with the proposed development. <br />5.4 Discussion of all proposed future on-site sources of nitrate to soil and groundwater and <br />the contribution of nitrate load from these sources to the project site: The future use of the <br />site will most likely include two new homesites. The existing residence with 6 bedrooms was <br />used to approximate the amount of people that could generate wastewater flow. It was <br />conservatively assumed that 100 gal/day would be generated for the first bedroom and 50 gal/day <br />subsequently for every other room, generating at a total of 350 gallons/day. The site is expected <br />to be able to handle up to 390 gallons/day, making the current and proposed flows sustainable. <br />There is a residence on the 2,.46 acre parcel. 350 gal/day of effluent was estimated were used for <br />the six bedroom house. The 2.46 acre parcel should have no problem with the 350 gallon/day <br />total of flows, but no major additions should be made without update to this report. <br />There is no residence or definite source of nitrates on the 2.00 and 2.69 acre parcel, but 250 gal/day <br />(4 bedroom house) were used assuming a residence could be built in the future. The 2.00 and 2.69 <br />acre parcels would have no problem with these small flows, but no major additions should be made <br />without update to this report. <br />The average total nitrogen concentration of domestic wastewater is about 20-85mg/L-N, <br />although 35-45mg/L-N is a better approximation (Crites and Tchnobanglous). The value selected <br />for this site was 40mg/L-N assuming this site shall experience a larger concentration. <br />The site will experience a process of denitrification as the soil naturally treats surface material <br />through natural forms. Denitrification is a process that occurs when bacteria uses oxygen in the <br />nitrate (NO3) and release nitrogen (Na) into the atmosphere. Denitrification can be variable to <br />the type of soils, chemical properties, moisture content and other variables. Based on the sandy <br />loams on site and the high percolation rates, this site's soil has moderate levels of denitrification. <br />It is expected that a site with soil of these characteristics shall have approximately about 20-30% <br />of denitrification. The value used for this site was 30%. <br />5.5 Calculate mass balance of nitrogen loading considering all potential sources identified <br />using Hanztch/Finnemore equation: Using the data mentioned within this report and the attached <br />Soil Suitability Report the mass balance of nitrogen loading for this site was calculated, this was <br />done using Hanztch/Finnemore formula. Based on the Hanztch/Finnemore equation, the 2.00 acre <br />parcel would contain a Nitrate Load (Nc) of 9.99 mg/L-N when the site is generating its peak flows. <br />