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SSS 3 ,3. 3.3 3.4,3.5,3.6. Applications on microfiche file with the EHD reveal that there 1) have been seven permits issued for repairs/replacements/additions to existing systems on Foppiano C3•Z 33) Lane. This can be considered a high number of permits. As referenced, the Morada area has always had a significantly high number of repair/replacement permits due to the clayey soil, and �33•�� may also be due to inadequate systems originally installed. <Ol79ti/ Z�tq The project site has relatively level terrain; consequently, there will be no need to incorporate design considerations for slopes within the disposal area. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS The United States Department of Agriculture- Soil Conservation Service (USDA-SCS) indicates CI ti I the on-site soils to consist of Jacktone clay(#180). As noted from the perc test results,this clay I soil type possesses slow permeability. SSS§ 5.2. The surface and subsurface soil investigation and testing began on June 9, 2012 with the drilling of the test borings using a B-24 Mobile Drill Rig and solid stem auger. Soil samples for chemical analyses from the 42 inch depth representative of the future leachline trenches and the 24.75 ft depth representative of the future seepage pit were retrieved from the soil cuttings. NLS§ 1.1,1.2. As the noted on the A&L Laboratory Soil Analysis Reports, the chemical analyses of the two soil samples quantify several constituents that influence nitrate loading from this project. The important parameters for nitrate loading assessment are the organic matter,pH, cation exchange capacity(CEC), clay content, along with nitrate-nitrogen content of the soil. As noted, the organic matter in the surface soils is low and actually more than doubles at the 24 ft depth. A low surface soil organic matter may be attributable to the fact the property has not been farmed in many years. The deeper organic matter occurred millennia ago. Organic matter is / needed for denitrification and could be a reason for decreased nitrate concentrations in the groundwater in this area. The nitrate-nitrogen concentration is 8 ppm at 42", but almost doubles in concentration at the 24 ft depth to 15 ppm. This increase in nitrate-nitrogen concentration suggests mobility of nitrate, but �.� this concentration apparently could be significantly higher if not for the clay soils and organic matter. Because septic effluent is composed predominately of ammonium (NH4),the pH, along with the CEC, are significant influences on ammonium molecules. The pH of the soil is very slightly alkaline which may have little effect on ammonium formation and stability. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. Cation Exchange J Capacities of the soil samples are high due to the high clay content. This means there is a large potential for the retention of ammonium molecules for microbial uptake, and denitrification potential. 3