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The property is bound to the north by a residential subdivision on public well service; to the east by a walnut orchard; to the west is a mobile home park; and to the south are rural residential structures. SSS§ 2.1. The surrounding land use of residential structures on septic systems and adjacent agricultural land use which has been in production for many decades, may have contributed to the potential of creating a nitrate problem. Surrounding land use is evidenced by the aerial Google/Soil Map photo in Appendix C. B. SOIL PHYSICAL AND CHEMICAL CHARACTERISTICS NLS §1.0,1.1. To analyze the subsurface soils, samples were retrieved from proposed Parcel 1 and proposed Parcel 3, since these Parcels are on either side of the property. Soil samples were retrieved with a truck -mounted drill rig, which were then converted to the deep perc test borings. Samples were obtained from the depths referenced in Table 1 below. NLS§ 3.3. The soil samples were submitted to A & L Western Agricultural Laboratories for analytical testing under the attached Chain of Custody, found in Appendix C. As noted, several constituents were analyzed. The main constituents tested relating to nitrate loading include the organic matter content, pH, Cation Exchange Capacity (CEC), and the nitrate -nitrogen content. The constituents listed above also contribute to the denitrification capacity of the underlying soil, which from the test results, appears to be significant since nitrate -nitrogen concentration is low at every tested depth. Denitrification capacity is predominately dependant upon: 1.) Abundance of an organic carbon substrate, 2.) High soil moisture content leading to an anaerobic environment, and 3.) High soil pH (alkaline). Considering the property has been farmed for the past several decades and was recently farmed in wheat straw, concentrations would be expected to be higher. To grow this last wheat crop, an approximate application of 150 units (lbs/acre) of nitrogen must have been applied. The organic matter content of the subsurface soils are of a low percentage which was to be expected; however, the pH is alkaline for all of the soil samples. Nitrogen in septic tank effluent consists of approximately 75% N in the ammonium ion (NH4') form and 25% N in the organic form. If the ammonium ion is bound and eventually utilized by microorganisms, nitrification is impeded. The Cation Exchange Capacity (CEC) can have significant influence on ammonium. The CEC measures the ability of the soil to theoretically trap, hold and convert ammonium molecules. Soil profiles from both borings have a medium -to - high CEC, which should increase the retention of ammonium molecules for microbial uptake and suppression of nitrification. SSS§ 5.2, 5.3, 5.4, NLS §1.2. In addition to the analytical chemistry completed on the soil samples, Particle Size Analysis (Soil Texture) was also completed. The soils have been classified by the United States Department of Agriculture - Natural Resources Conservation Service (USDA- NRCS) classification (e.g., silt loam, etc.). The Unified Soil Classification System (USCS - e.g., lean clay, silty clay CL-ML/CL) has been used on each of the EHD Percolation Test Rate Field Forms to identify the soil as encountered in the exploratory/percolation test borings. -2- Chesney Considtina