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Percolation Test Results SSS§ 6.2 To assess the permeability of the disposal area adequately, test depths were 24 inches, 42 inches, 9 ft and 15 ft below existing grade, giving a comparatively detailed observation of subsurface permeability within the disposal area. Only the 42 inch and 9 ft test depths are recognized as "official" "unofficial"tests since the they two test depths 24 inch and 15 ft are uno Y I officral by EHD, while the o p ( ) are out of typical test depth range. The shallow test depths represent (in all probability), the soil- effluent interface of a disposal system that may be installed in the future. The deep tests give data on the deeper soil permeability. SSS§6.3 On August 9, 2006, the perc test borings were drilled with a truck-mounted B-24 Mobile Drill Rig for both test areas. The sidewalls of the 24 and 42 inch perc test borings were scored with a pry-bar and the loose material removed. By scoring the sidewalls, this "opens"potentially smeared surfaces. On August 9, 2006, two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted in each of the four test borings for the NEC perc tests. Each test ex boring was pre-saturated with 24 inches of water (2x the standard) at 0800 hrs, approximately 24 hrs before the start of testing. SSS§6.4, 6.5 On August 10, 2006, percolation testing commenced for the four NEC test borings. No standing water was observed after the 24-hr soak period in the test borings, except for the 15 ft test boring which had approximately 3 inches of standing water. Consequently, EHD Pere Test 1 Procedure#1 was done for the 15 ft test boring in which approximately 3 inches of water was poured 1 into the test boring to bring the level to 6 inches, and the testing done over a four-hour period. EHD Test Procedure #2 was conducted for the remaining three test borings. Pere testing was done over a four-hour period to induce maximum soil saturation. The 15 ft test boring had failing rates and illustrates very slow hydraulic conductivity at this depth. After these perc tests were completed on August 10, 2006, the test borings for the SWC test borings were prepared. After the approximate 24 hr saturation period, only the deep 15 ft test boring had 4 inches of standing water. Perc testing commenced for the four SWC test borings on August 11, 2006. Pre-test and test procedures were identical for both test sites. Test results for the SWC also reveal favorable permeability for the 24 inch,42 inch and 9.5 ft test boring, but a very slow rate for the 15 ft test depth. All of the perc tests were witnessed by Ms. Amanda Boertien of EHD. The test results reveal that the NEC of the disposal area has a higher rate of permeability(closely related to saturated hydraulic conductivity)by a rough approximate factor of 2x for each of the tested depths. There appears to be no corresponding explanation for these differences in permeability with respect to soil type,but differences in soil densities at the exact depth of testing could be a factor. A summary of the perc test results with corresponding theoretical application rate in gallons of effluent accepted per square foot of soil, per day are found in Table 2 for the NEC of the disposal area and Table 3 for the SWC area of the disposal area. On average, the upper soils of the NEC of the disposal area possess an application rate of 0.738 gallons/ft'/day, until the water reaches a depth of 15 ft where permeability reduces by one-third. For the SWC. of the disposal area, the application rates are 0.574 gallons/ft'/day down to 9.5 ft. At 15 ft, permeability also decreases by a factor of 3x. Page-7- Chesney Consulting