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It is my understanding that the crops to be grown on the acreage have been, and will continue to be (barring unforeseen economic decisions) forage for dairy cattle since Mr. Machado and Mr. Borges are in the dairy business. These forage crops include silage corn in the spring and summer and oats/winter mix in the fall and winter. The Western Fertilizer Handbook indicates that silage corn requires 250 pounds of N per acre per growing season and oats require 115 pounds N per acre per growing season. This past winter growing season, oats were grown on the property acreage. Fifty units (pounds per acre) of N were flown on the crop, which is less than half of the crop requirement. As noted from the soil analytical test results, after the oat crop was harvested, the 42 inch and 10 foot depth soil samples reveal very low nitrate-nitrogen concentrations at 4 ppm and 3 ppm, respectively, indicating nitrogen uptake by the oat crop. Additionally, the 25 foot depth sample also reveals a very low concentration of nitrate-nitrogen (3 ppm) equivalent to the 10 foot concentration. There are various formulas and methods to estimate nitrate loading from septic systems. The following calculations are based upon using a conventional or traditional type of septic system consisting of a septic tank, leachlines and seepage pits, or sumps. The nitrate loading method presented is the Hantzsche/Finnemore Equation. It is generally regarded that this equation is the most representative and accurate regarding nitrate-nitrogen loading from septic systems. The primary variables involved in quantifying nitrate impact to the underlying groundwater are Total Nitrogen concentrations, volume of yearly wastewater flows, extent of denitrification, and evapotranspiration potential. Denitrification capabilities of the indigenous clayey surface and shallow subsurface soils are expected to contribute to the denitrification potential. Ammonium retention in the clay soils that are present should also be a factor, as has been observed in other projects with similar soils. Evapotranspiration was not factored in the nitrate loading calculations; however, it may be a significant part of wastewater management and consequently nitrate-nitrogen loading. In addition, future agricultural production that may occur on each individual two-acre parcel leased by the lessee has also not been taken into consideration since it is unknown at this time. The following calculations demonstrate that the nitrate loading potential for the project originating from proposed septic system influence is nil, primarily due to the large land area(444 acres). Hantzsche/Finnemore Equation INW(1 - d) +R Nb Nr= (I+R) Where: Nr= Resultant average concentration of nitrate-nitrogen in recharge water -ppm NO3-N. I = Volume rate of wastewater entering the soil averaged over the gross developed area in inches per yr. Total wastewater volume: 490 gals/house x 22 houses (fficmd.s.ond ;,dwclug)_ 10,800 gpd x 365 days/year=3,942,000 gals- 7.47 gals per fl3 = 528,000 cu ft of wastewater. Does not account for Eva op transpiration. Page -8- Chesney Consulting