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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 and south is commercial and industrial. To the west is agricultural land and to the east is rural residential, all on onsite wastewater treatment systems. SSS§3.1,3.2,3.3,3.4,3.5,3.6,3.7,6.8. Applications in the EHD microfiche database indicate there was never a septic tank located on the subject property in the location of Robertson's facility. A total of seven permits have been issued for repairs/replacements/additions to existing systems within the one-half mile radius study area from the property. This can be considered a medium-to- high number of permits. Given the slow permeability of the deeper soils, only the shallow soils appear to managing effluent flows but with hastened biomat formation, septic system longevity is limited and system failures occur. The project site has level terrain; consequently,there is no need to incorporate design considerations for slopes within the effluent disposal area. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS The United States Department of Agriculture- Soil Conservation Service (USDA-SCS) indicates the property soil consists of Veritas clay(#266). The effluent disposal area will be installed in a lighter soil material. SSS§5.2. The surface and subsurface soil investigation began on November 20,2019 with the drilling of a 36" and a 96" deep perc test borings. The borings were drilled using a truck-mounted B-24 drill rig, adjacent to the proposed location of the disposal area so that no disturbance of the effluent accepting soil profile would occur. NLS§ 1.1,1.2. Composite soil samples from the test borings were retrieved for chemical and particle size analysis from each depth. As noted on the attached A&L Laboratory Soil Analysis Report, chemical analyses of the retrieved soil samples quantify several constituents that influence nitrate loading for this project. The important parameters for nitrate loading assessment are the organic matter, clay content,pH, cation exchange capacity(CEC), and the nitrate-nitrogen content of the soil. The organic matter at the 3-ft depth has an abnormally high OM rating, with the 8-ft depth at an OM percentage commonly observed. Organic material must have been buried in this location in the past. Although this high OM concentration suggests there is a potential for future nitrate formation,this was not observed in the nitrate-nitrogen concentration at the 8-ft depth. 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 alkaline which may have a positive effect in promoting ammonia formation and not ammonium formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. Cation Exchange Capacities of the soil samples illustrate a CEC of 13.2 and 14.7 meq/100 g,respectively. Page -2- Chesney Consulting