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August 3, 2004 NOA Project Number: E04081A Table 6. Summary of Percolation Tests. Test No., Percolation Percolation Rate Test Comment Date Tested Test Depth (minutes/inch) Duration (see notes) PT shallow,7-22-04 3.06 <2 1 hr Satisfactory ercolation rate. Note: A satisfactory percolation rate for a"shallow" tis les han or equal to 60 minutes per inch. �6.5 Discussion of Percolation Test The soils within the sewage disposal area have demonstrated a satisfactory percolation rate in accordance with the requirements of the EHD. The soils of the Site appear to be suitable for a septic system utilizing shallow leach lines and seepage pits. 6.6 Required Size of Septic System The EHD Sewage Standards should be followed to size the septic system. Due to the fast percolation rate, we would suggest the use of a filter bed type system. 7.0 NITRATE LOADING ANALYSIS Because of the concern of nitrate leaching into ground water from septic systems, a nitrate loading analysis was required by the EHD for the proposed facility to measure the potential concentration of percolating effluent and rain fall over the long term. Where percolating effluent leaches into the ground, ground water quality may be impacted to some degree should the effluent reach ground water. The method utilized for the nitrate loading analysis is based on a simple mass balance formula, discussed in a published article by Hantzsche and Finnemore (1992) which provides a convenient and simplified method to estimate long-term ground-water nitrate impacts on an area-wide basis. Hantzsche and Finnemore found that over a long period of time, water quality in the upper saturated ground-water zone closely approximates the quality of percolating recharge waters. They believe that their method is a good planning tool and provides useful information to planners and local officials but with some real limitations. In their article published in 11