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Fsoil testing included percolation testing and particle size analysis, correlated with on rates to ensure management of the wastewater flows. Chemical testing included for the constituents that influence nitrate loading. the recently measured water table correlated with the existing filter bed depth to ensure that adequate soil depth distance was in compliance. II. SOIL SUITABILITY STUDY FINDINGS A. SUBJECT PROPERTY AND SURROUNDING STUDY AREA INFORMATION SSS§ 1.1 Surrounding land use, particularly to the south, west and north of the project is, and has been, in agricultural production for many decades. To the east is Interstate 5, the City of Lathrop, and commercial facilities. New development within the City of Lathrop is occurring approximately three miles to the south, and is projected to proceed north along the west side of Interstate 5. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS The United States Department of Agriculture- Soil Conservation Service(USDA-SCS) indicates the majority of the on-site soils to consist of a Manteca fine sandy loam (#196), with the extreme northeast corner of the property composed of Veritas fine sandy loam (#266). NLS§ 1.1, 1.2. Chemical analysis of a soil sample that was retrieved from the bottom of the 36-inch depth percolation test boring is noted on the A&L Laboratory Soil Analysis Reports found in Appendix B. The important parameters for nitrate loading assessment are the organic matter,pH, cation exchange capacity(CEC), clay content percentage, and nitrate-nitrogen content. The nitrate-nitrogen and organic matter in the soil are very low. Previous soil testing for the 2007 report indicated high soil nitrate-nitrogen from previous land use. This decrease in soil nitrogen concentration may be attributed to high nitrate soil mobility and denitrification. Since 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 alkaline which may inhibit ammonium formation and stability, and may create a propensity for ammonia(NH3) formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. The Cation Exchange Capacity of the soil sample was surprisingly medium considering the sand concentration. A lower CEC would have been expected. This suggests there is some potential for the retention of ammonium molecules for microbial uptake, and suppression of nitrification. 2 Chesney Consulting