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II. SOIL SUITABILITY STUDY FINDINGS i A. SUBJECT PROPERTY AND SURROUNDING STUDY AREA INFORMATION SSS§ 1.1. Land use surrounding the subject property Yis predominately agricultural production land, ranches/ranchettes and sparse rural residential structures. SSS§3.1,3.2,3.3,3.4,3.5,3.6,3.7, 6.8. Applications on EHD microfiche files were reviewed to determine the number of permits issued for repairs/replacements/additions to existing systems within the one-half mile radius study area from the subject property. Only one repair was found at 25212 N. Cherokee Lane. The septic systems in this locale are very sparse so data is limited. Given the clay content of the on-site and surrounding soils, septic system longevity would assumed to be limited and failures would be occurring regularly. However, the three houses that occupy the properly were built in 1965, 1984 and 2003. There have been no failures with these systems and the only maintenance done is occasional septic tank pumping. 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 SSS§ 5.2. The United States Department of Agriculture -Natural Resource Conservation Service (USDA-NRCS) indicates that most of property soils are San Joaquin loam(#239),with the northwest and southeast corners a San Joaquin complex. The surface and subsurface soil investigation began on March 4, 2018 with the drilling of an exploratory boring to log underlying soil characteristics near the center of the subject property, followed by one shallow and one deep perc test borings on each proposed Parcel. No water(perched water table or groundwater)was encountered. Although septic systems currently exist on two of the Parcels, EHD still requires that perc tests be performed on these Parcels. NLS§ 1.1, 1.2. Auger cuttings were obt 'ned for chemical analysis from the bottom of the-3-ft test boring of Parcel 1 and from the 20- ft deep erc test boring on Parcel 4. As noted on the A&L Laboratory Soil Report in Appendix- lyses 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 is 1° which translates to an Estimated Nitrogen Release (ENR) of 40 lbs. of N/acre. This is an insign<i=t concentration of nitrogen over a one acre area. The soil nitrate-nitrogen concentration is very low at 1 ppm at the shallow depth and 3 ppm at the 20-ft depth. Because septic effluent is composed predominately of ammonium(NH4),the pH, along with the CEC, are significant influences on the ammonium molecules. Page -2- Chesney Consulting