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- Percolation Test Results To asses a enneability of Disp sal r a and#2 adequately,per ti test_depths were_ drilled t 24 ' ch ;42 c s, 8j d-1�5 ft elow existing grade - ea#1 and drilled to depths 1 of 24 in., 42.in., 6 ® and 1 .2 ft.f r a 2. These depths give-a co ively detailed observation of subsurface perrneabi ' n the disposal area. In accordance with the request of EHD, no test de to exceed 12 feet to maintain a-10-ft distance between the bottom of a test boring and th ass,, ed ater table depth of--22 ft. The standing water level of the on-site well was measured to e 24 ft bel grade on June 5, 2008. Only th 42 i , and e 1.1 ft epth perc tests for both Dispersal Areas are recognized0"officialby EH a the oth -due-Gest depths (24 inch, and 8 ft and 6.2 ft depths) are "unofsince theyare out of typical test depth range. These deep tests give data on-the deeper permeability. The shallow test depths represent the approximate soil-effluent interface depth for a r drip dispersal system. ' On May 30, 2008, all eight perc test borings were drilled with a truck-mounted B-24 Mobile Drill Rig near the center of each Dispersal Area. Test locations are illustrated on the referenced CSHQA Site Plans. 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, June 4, 2008,two inches of fine gravel was'placed at the bottom and three-inch perforated PVC pipe was inserted in each of the eight.test borings. The four test borings for Dispersal Area#1 were pre- saturated with 24 inches of water(2x the EHD.standard) at 0800 hrs, approximately 24 hrs before the start of testing. _ On June 5, 2008`; 0730 hrs, percolation testing commenced for Dispersal Area#1. No standing water was observed after the'24-hr soak period-in any of the test borings; therefore, EHD Test Procedure#2, was conducted. Pere testing was done over a four-hour period to induce maximum soil saturation. Before completion of the Dispersal Area#1 tests, the perc test borings for Dispersal Area#2 were pre-saturated with 24.inches of'water'at 0815 hrs. No-standing water was observed in any of the Disposal Area.#2 test borings.4fter the 24-hr soak period. Pe-rc testing commenced for the four Dispersal Area 42 test borings on-June 6, 2008 at 0730 hrs. Test results for:Dispersal Area#1 reveal exceptionally favorable permeability at the 24-inch test depth, with slower rates at the 42 in., 8 ft and 11.5 ft test depths. Test results for Dispersal Are-a-#2 indicate slower permeabilities in comparison to Dispersal Area #1. As with the original testing in 2006, there appears to be no corresponding explanation for these differences in peimeability with respect to-soil type, other than at the 8-ft depth in Area#1 where a heavier-clay content soil was encountered. " A summary of the perc test results with_corresppnding theoretical application rate in gallons of effluent accepted 'per square foot of soil, per day are found in Table 2 and Table 3 for Dispersal Area#1 and Area#2; respectively. In addition,the 2006 test results are.also included for comparison purposes: Page-4- Chesney f Chesney Consulting