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B. SOIL PHYSICAL CHARACTERISTICS The surface and subsurface soil investigation and testing began with hand-drilling one 12",one24" and one 36" deep percolation test borings in the proposed mound system effluent disposal location. The surface soils to a depth of 12" is a dark browniblack,high clay and organic matter content soil with 3.4"fissures caused by clay cracking. From 12" to 24",the soil is a tight,yellowish light brown,silty clay-clayey silt material exhibiting the slowest permeability characteristics of the three test depths. Below 24",the soil is a dark brown,tight, lean clay. The length of the subject property is 1,150 It S-N with an elevational drop of-12 ft,so the property has a northerly downward slope of slightly less than 1%grade. One percent grade is the maximum slope for the installation of a mound system without having to take mitigating design factors into consideration. On grades greater than I%, effluent can congregate on the downward side of a mound which must be compensated for through design modifications. The United States Department of Agriculture-Soil Conservation Service(USDA-SCS) indicates the on-site soils to consist of Stomar Clay Loam. This soil type is classified as a lean clay with some silt. Permeability is very slow, as was observed in the percolation testing. C. PERCOLATION TEST RESULTS The percolation tests were completed in the locations depicted in the Site Plan found in Appendix B. The three test depths are referenced above, =aveeability tively detailed observation of subsurface , permeability in these three strata. Onlydepth is recognized as`official'by EHD. The test depths can be considered to represent throughout the effluent receiving soil profile. On July 16,2012,the three perc test borings were drilled in the referenced locations. The sidewalis of each boring were scored with a pry-bar to open potentially smeared sidewalls. Two inches of pea gravel was placed at the bottom and three-inch perforated PVC pipe was inserted in each test boring. Each boring was then pre-saturated with water at 3x each bore hole volume at 0900 hrs,24 hrs before the start of testing. This greatly exceeds EHD pre-saturation standards. On July 17,2012,percolation testing commenced No standing water was observed after the 24-hr soak �_pel_iod in any of the three tos+"s. Consequently,EHD Pere Test Procedure#2 was conducted in which testing was done over a four hour 'od to induce maximum soil saturation. A summary of the perc test 1,7 results with corresoenditlgappljpa ton rates in gallons of effluent accepted per square foot of soil,per day are found in Table 1 below for the proposed disposal area: TABLE 1 PERCOLATION TEST RESULTS FOR THE DISPOSAL AREA MOUND SYSTEM WITH CORRESPONDING APPLICATION RATES IN GALLONS/FT'/DAY 12 INCH DEEP PERC TEST BORING 41.7 min/inch / 0.472 gallons/ft/day PERCOLATION RATE/APPLICATION RATE 24 INCH DEEP PERC TEST BORING 83.3 min/inch / 0.235 gallons/ft'/day PERCOLATION RATE/APPLICATION RATE F36 INCH DEEP PERC TEST BORING PERCOLATION 62.5 'nhnch / 0.335g RATE/APPLICATION RATE AMhcetiwi Rates adaraed from Caff�'a Smte W'mer Resamees Cauca!Board Guidelmesfi� the De.+tgn of Mound Seenge Samemv and L bead m the Pm R W. 3