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II. SOIL SUITABILITY STUDY FINDINGS A. SUBJECT PROPERTY AND SURROUNDING STUDY AREA INFORMATION SSS§ 1.1. Land use to the immediate north, east and west is rural residential, all on septic systems and wells. To the south is an auto dismantling company. SSS§3.1,3.2,3.3,3.4,3.5,3.6,3.7,6.8. Application permits found in EHD online files were available for review to determine the number of permits issued for repairs/replacements/additions to existing systems found on Carpenter Road exclusively. As noted in Appendix J, the number of permits are quite extensive on this Road alone. A total of 31 permits were found. Given the hardpan/clay content of the on-site and surrounding soils, septic system longevity can be considered limited without installing deeper septic system structures, such as sumps and preferably seepage pits. Many of the permits for repairs/replacements are decades old. This indicates that originally installed systems were insufficient in size to manage ultimate effluent flow volumes, in addition to being installed in the shallow, slowly permeable soils. Found in Appendix I, are the EHD permits pertaining exclusively to the subject property. Aerial photos illustrate the locations of the on-site wells and existing septic systems. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS SSS§ 5.2. The United States Department of Agriculture -Natural Resource Conservation Service (USDA-NRCS) indicates the property soils are 85% Jacktone clay, 4%Archerdale clay, 3% Unnamed, 3% Hollenbeck clay and 3% Stockton clay. NLS§ 1.1, 1.2. Auger cuttings were sampled from the bottom of the 42 inch, 12-ft and 25-ft perc test borings for chemical analysis. As noted on the A&L Laboratory Soil Report in Appendix C, analyses of the soil sample quantifies a number of constituents that influence nitrate loading for this project. The important parameters for nitrate loading assessment are the organic matter,pH, cation exchange capacity(CEC), and the nitrate-nitrogen content of the soil. As noted, the organic matter from all three depths starts at 0.6%at 42 inches, followed by 0.5%at 12 ft and 0.6%at the 25-ft depth. This translates to an Estimated Nitrogen Release(ENR)of approximately 40 lbs N/acre. This is an insignificant concentration of nitrogen release over a one acre area. The soil nitrate-nitrogen concentration at the three depths was determined to be an average of 9 ppm, which can be considered a concentration in equilibrium. Because septic effluent is composed predominately of ammonium(NHA the pH, along with the CEC, are significant influences on the ammonium molecules. The pH of the soil is alkaline at the proposed soil-effluent interface which has a positive effect in promoting ammonia and not the nitrate substrate ammonium within the alkaline soil environment. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. The CEC illustrates a high potential for the clay fraction of the soil profile to retain ammonium molecules that remain as ammonium in the soil environment. Nitrification is also hindered due to the alkaline pH and the anaerobic clay micro-sites. Page -2- Chesney Consultin;