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FrTheLF showed interesting soil perc test results between the 36 and 42 inch test depths. The perccrease by 4.5x in this distance, obviously indicating a coarser material at the 42 inch depth. an be beneficial with regard to nitrate loading under the following scenario: colating water encounters this coarser fraction,water does not immediately enter this stratum. oabove it must become relatively saturated before water will flow into this coarser fraction. This can create saturated soil microsites that are anaerobic and conducive for the promotion of denitrification. Hardpan stratum was not encountered in our drilling procedures. It is a possibility that it exists in the disposal areas. Hardpan should be investigated with a backhoe prior to the installation of the filter beds for the Office Trailers and Office Building. If hardpan is encountered, Chesney Consulting must be notified. From the soil chemistry results, it appears that denitrification is substantially occurring between the 5, 10 and 15 ft depths in the ELF, and between the 5 and 10 ft depth in the WLF(See Table 1)as evidenced by the significant decrease in nitrate-nitrogen concentrations. This precludes a wastewater system design with a denitrification cycle as stated in Item 3 b of the Conditions of Approval. The water table analytical chemistry results obtained for the ELF was to be expected at 156 ppm nitrate. The test results for the WLF were a inexplicable in that no nitrate was detected and the water was incredibly salty. It can be reasonable concluded that percolating effluent that reaches the water table will have a significantly better chemistry than what is in-situ and will lead to a dilution effect. Because of the apparent high denitrification potential in the soil profile for both disposal areas, it is our opinion that high nitrate concentration increases in the water table can be theoretically mitigated based on the soil test results. NLS§4.2, SSS§ 6.7 The design of the filter bed that will be placed high in elevation will take advantage of the indigenous soils that possess favorable qualities to inhibit nitrification. For nitrification that does occur, the anaerobic microsites at deeper elevations within the underlying soils promote denitrification. The denitrification potential in combination with landscape plants in the filter bed area should also reduce nitrate impact by evapotranspiring a percentage of the effluent during favorable weather times of the year(i.e., April through September). SSS§6.8 The Average Daily Flow is calculated to be 1,586 gals/day for the ELF. The Application Rate at the soil-effluent interface is 0.643 gals/ft'/day based upon the obtained perc rate of 20.8 min/in at the 24 inch depth. This suggests a disposal area of 2,466 RZ. Considering conservative criterion, EHD equations are applicable to arrive at a total filter bed disposal area size of 1,900 ft . NLS§ 4.1 The nitrate loading potential calculated on Page 14 indicates the percolating effluent may have a resultant nitrate concentration of 8.8 ppm, which is below the drinking water Maximum Contaminant Level (MCL). These calculations rely on numerous factors which are extremely variable and unknown at this time. These factors and the effluent quality itself can only by quantified after complete build-out of the project and an actual effluent sample obtained for analysis. 21 Chesney Consulting