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I` 4 C. PERCOLATION AND'INFILTRATION TEST RESULTS SSS§ 6.2. To assessthe:permeability and the infiltration capabilities of the proposed filter bed disposal area, two "EHD Official" percolation tests and three-"Unofficial"percolation tests were completed in the locations depicted in the Site Plan found in Appendix D. The "official"test depths. were 36 and 42 inches below existing grade in:the primary disposal area, giving a comparatively detailed observation of subsurface permeability at these two strata. Due to what was interpreted to be a perc test anomaly at the 42 inch test depth; two additional "unofficial" tests were conducted, again at the 36 inch depth and at the 40 inch depth. A 24 inch unofficial test was also conducted. This 24 inch shallow test was conducted to measure any changes between"surface" and deeper "subsurface" soils, which was definitely-observed. SSS§ 6.3. -On June 10,'2009, three perc test borings were drilled in the referenced locations. These j tests included the two EHD official perc tests, and the 24 inch unofficial test. The sidewalls of each boring were scored with'apry-bar to open potentially smeared'sidewalls. 'Two inches of fine gravel was placed at the bottom: and three-inch-perforated PVC pipe was inserted in each test boring. The test borings were pre-saturated with 12 inches of water at 0900 hrs; 24 hrs before the start of testing. SSS§ 6.4, 6.5. On June 11,:2009, percolationtesting commenced for all three test borings referenced above. No standing water was observed after the.24-hr soak period in the three test borings. Consequently, EHD Pere Test Procedure 42 was.conducted Jn which testing was done over. a four-hour period to.induce maximum soil saturation. The test results indicate a failing per-c'rate of 62.5 min/in for the 24 inch deep test boring and a failing rate of 83.3 min/in for the 42,inch test°boring. The 36 inch test boring had a relatively rapid perc rate of 11.9 min/in. in discussions with EHD.Sanitarian Ted Tasiopoulos at the end of these tests, it was decided that the 42 inch test boring must be an anomaly since the test result should be approximately equal to the 36 inch test boring: This anomaly is inexplicable since nothing unusual was observed in drilling the test boring. It was-decided to do two additional "unofficial"tests at 36 and 40 inches near these two initial tests. On June 16, 2009, these two additional-tests yielded results of 20.8 min/in for the 36 inch test depth. and.8.9 min/in for the 40-inch test depth. A summary of the perc test results for the proposed disposal area with corresponding application rates-itfgallons=of e fluent accepted per square foot of soil, per day are found in Table 2 and Table 3: TABLE 2 EHD OFFICIAL COLATION TEST ;RESULTS FOR THE DISPOSAL AREA ` `wWITH CORRESP NDING`APP LICATION::RATES JN GALLONS/FT2/DAV,. :_ 36 INCH DEEP ERC TEST BORING 11.9 min/inch / 0:771 gallons/ft'/day ERCOLATIO ATE/APPLICATION RATE, 42 INCH DEEP PERC TEST BORING 83.3 min/inch / 0.235 galloin s/ftz/day PERCOLATION RATE/APPLICATION RATE- Application Rate adapted from,California Slate Water Resohrces Control Hoard Guidelines for the Design of Sewage Systems and is based on the Pere Rate- -5 Chesney Consulting