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CONCLUSIONS AND RECOMMENDATIONS NLS§ 4.2. The shallow subsurface soils underlying the subject property where the new disposal area is to be installed, reveals a sandy loam soil structure at both the shallow and deeper depths, with acceptable permeability and an apparent high degree of natural denitrification potential. Although an apparent 90%denitrification percentage was observed through quantitative analysis, it is my opinion that the percentage of soil organic matter and soil matric potential gradient that may occur, is less than what would precipitate such significant denitrification. Consequently, a generally regarded denitrification percentage of 30%as described in Ref. 8, Pg 10 was used in the nitrate loading equation. The septic tank should be installed with the top of the tank 4" above final grade to ensure that the OWTS remains as high in elevation as possible. There must be an 8 ft separation distance between the soil-effluent interface and the highest anticipated depth to groundwater. This may be interpreted to be between 10 and 15 ft. Consequently,this separation distance can be achieved by installing the tank at this elevation with 6" of soil cover and 1 ft of drain rock below the perforated drain pipes. NLS§4.1. The nitrate loading calculations show the resultant effluent from the entire subject Parcel containing both a primary and second unit dwelling will theoretically possess a concentration of approximately 7.1 ppm as nitrate-nitrogen; under the Maximum Contaminant Level (MCL) of 10 ppm nitrate-nitrogen. The application rate was determined from the perc rate to be 0.714 gallons/ft2/day. If leachline trenches are installed,the trenches can manage: 240 LFLL x 4 ft2= 960 ft2 x 0.714 gallons/ft2/day 685 gpd. If a filter bed is installed,the disposal area will be 720 ft2 of floor area. Therefore,the filter bed can manage: 720 ft2 x 0.714 gallons/ft2/day= 514 gpd. The existing on-site domestic well reveals a nitrate-nitrogen concentration that exceeds the Maximum Contaminant Level (MCL)by 5.7 ppm. The well water must be filtered under E14D requirements by reverse osmosis. NLS§ 4.2. All OWTS (septic systems)will eventually fail. A reasonably long lifespan of both the primary OWTS and the second unit modular dwelling can be expected based on the receiving soil characteristics,the perc rates obtained, and the lifespans determined from the system permits. Pabe -8- Chesney Consulting