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C. PERCOLATION AND INFILTRATION TEST RESULTS SS § 6 S .�4_To assess the permeability and the infiltration capabilities of the disposal area soils, the aforementioned two percolation test borings were completed in the locations depicted in the Site Plan found in Appendix C. The test depths at 24 and 40 inches below existing grade give a comparatively detailed observation of subsurface permeability at these two strata. Only the 40-inch test depth is recognized as`official'by EHD,while the 24-inch depth gives data on shallow percolation. The test depths can be considered to represent the average permeability throughout the effluent receiving soil profile. SSS§ 6.3�_On February 14, 2007, the two perc test borings were drilled in the referenced locations. The sidewalls of each boring were scored with a pry-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. On February 15, 2007, each boring was pre-saturated with water at 3x each bore bole volume at 1000 hrs, 24 hrs before the start of testing. SSS§ 6.4, 6.5. On February 16, 2007, percolation testing commenced. No standing water was observed after the 24-hr soak period in either of the two test borings. Consequently, EHD Pere Test i Procedure#2 was conducted in which testing was done over a four-hour period to induce maximum soil saturation. The test results indicate relatively equal perc rates between the 24 inch and 40 inch perc test depths, at 10.4 minutes per inch(min/in) and 14.7 min/in,respectively. A summary of the perc test results with corresponding application rates in gallons of effluent accepted per square foot of soil,per day are found in Table 2 for the proposed disposal area: TABLE 2 qRP RCOLATIONNEST RESUL''1S 'OR`I"H1 DIS�Ql��SAATH CORRESPOND1fPPLICATION RAT 'IN.GI,LO1;DAY �l 24 INCH DEEP PERC TEST BORING 8.9 inch / 0.857 gallons/ft/day PERCOLATION RATE I APPLICATION RATE 40 INCH DEEP PERC TEST BORING 22.7 inch / 0.614 gallons/ft lday PERCOLATION RATE I APPLICATION RATE Application Rate adapted from California State Water Resources Control Board Guidelines for the Design ofSeKage Systems and is based on the Pete Rate. Double Ring Infiltrometer Tests In addition to the conventional percolation tests described above, a double ring infiltrometer test was conducted near the percolation tests. This test was done under ASTM Test Method for Infiltration Rate of Soils in Field Using Double-Ring Infiltrometers - D3385. The infiltrometer test measures the incremental infiltration velocity, which is the quantity of flow per unit area, over an increment of time (cm3 —, cm'/sec). Infiltration is the downward entry of liquid into the soil and is measured by the infiltrometer. 5 Chesney Cons Il lting