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The soil testing has found the indigenous surface soils to contain a sand and loamy sand material that has rapid permeability. Management of wastewater effluent by the surface soils down to 42 inches will easily occur within the proposed filter bed, but must be mitigated due to excessive permeability by the introduction of peat material at the soil-effluent interface. II. SOIL SUITABILITY STUDY FINDINGS A. SUBJECT PROPERTY AND SURROUNDING STUDY AREA INFORMATION SSS§ I.I. Surrounding land use consists of commercial, industrial and residential properties, all of which have on-site domestic well water and septic systems. SSSO.1,3.2,3.3,3.4,3.5,3.6,3:7, 6.8. Applications on files with the EHD reveal that there have bee iio�rmits issued for repairs/replacements/additions to existing systems within the one-half mile�ius study area. This can be attributed to the indigenous sandy soils throughout this area. The project site has level terrain; consequently, there i no ed to incorporate design considerations for. slopes for the future 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 primarily of Delhi loamy sand (#142)and Manteca fine sandy loam(#196) in the extreme western edge of the property. The Soil Survey states that permeability is excellent in these soils, which was observed in the percolation testing conducted. SSS§5.2. /+he surface and subsurface soil investigation began on July 27, 2015 with the drilling of 24 and 42-inch deep perc test borings. These borings were drilled in a location that was originally planned to be the location of the new septic tank and leachfield. This location has subsequently changed to the northwest of this test location, but still within the one hundred-foot radius of these initial tests. The new septic tank and filter bed disposal area is illustrated on the attached aerial photo. LS§ L D 1.1, Soil cutting samples from the 42-inch perc test boring were retrieved at the 24 and �-ineh depth for chemical analysis. No standing water, or saturated soil was observed at the bottom of this boring. As the noted on the A&L Laboratory Soil Analysis Reports, chemical analyses of the two 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. As noted, the organic matter in the surface soils is low, at 0.6%and 0.4%, respectively. These O.M. concentrations suggest that there is minimal potential for future nitrate forming from this organic matter and an equally low potential for denitrification of nitrate molecules that may form through nitrification. However, as nitrate that may form percolates downward, it encounters a higher porosity soil at the 42-inch depth in comparison to the 24-inch depth. From soil physics, it is known that water migration does not readily enter a higher porosity soil from a lower porosity soil until the lower porosity soil becomes saturated. Soil saturation creates anaerobic conditions, which promotes 2