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3.) The leachfield area based on the permeability of the soil eventually reaching a conservative long term application rate (LTAR) of approximately 0.25 gals/ft'/day due to biomat formation. Although the hydraulic conductivity test indicates a theoretical application rate of 3.0 gals/ft'/day, 0.25 gals/ft2/day is a safety factor of 12 and therefore, conservative. If conventional leachline trenches are installed for a second unit dwelling, three leachline trenches for a dual system, for a total of six trenches, and only one sq ft on each side of the leachline trench will accept effluent (this excludes the floor of the trench for a safety factor), then there will be: 200 sq ft/trench x 6 trenches total= 1,200 sq fl of application area. If the LTAR is 0.25 gals/ft2/day, then the trench sidewalls should accept: 1,200 ft2 x 0.25 gals/ft2/day= 300 gallons/day. In Section III C above, 270 gallons/day was used in the calculations (includes a safety factor of 1.5). 4.) The leachfield area calculated from the lineal feet required as calculated in Section 8.6 of the Sewage Standards: 1,200 gals BTC + 270 gals ADF = 1,470 CTC x 0.25 = 368 lineal feet of leachline (LFLL). 5.) Filter bed requirements (the most favorable septic system structure to install): 368 LFLL x 4 (clay soils) = 1,472 square feet x 2(dual system)= 3,000 square feet, or 55 feet square. 6.) Since the groundwater is comparatively deep, vadose zone, or soil monitoring under the disposal areas would be the most prudent method of monitoring. Since this study has determined baseline soil nitrogen concentrations, soil monitoring can correct potential problems much quicker than groundwater monitoring wells. From previous studies done in this area, theoretically, it may take a nitrate molecule more than seven years to travel down to the groundwater. It is important to note that all septic systems have a lifespan. This lifespan is dependant on several factors and is therefore difficult to determine. A 50% replacement area must be designated within the property boundaries in the event of failure. As described above in Section III B, another source of nitrate loading can be from lawns/ landscaping/gardens, which is estimated to be 24% and could be significantly higher. It is recommended not to use any nitrogen fertilizers on the lawns and landscaping to reduce nitrate loading from these areas. Due to the current nitrate concentration in the DeAngelis domestic well approaching the MCL, bottled water should be consumed for drinking and cooking purposes for both the primary residential unit and a potential second unit dwelling. Page -13- Chesney Consulting