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• These Studies have been conducted for eventual EHD requirements and for the referenced General Plan Amendment/Re-Zone Application. The primary wastewater disposal area and the required 100%reserve/replacement/addition areas that will serve the proposed commercial project have described and illustrated on the Site Plan produced by the general contractor for the project,DeGraff Development of Oakdale, CA. • Soil physical and chemical testing was conducted. Physical testing included percolation testing to determine soil permeability characteristics of the receiving soil profile. Chemical testing included analyses for the constituents that influence nitrate loading. • The capacities of the on-site soils were analyzed: 1.)For the ability to accept potential future wastewater effluent flows,2.)To assess the characteristics of the on-site soil to mitigate nitrate impact, and 3.)To quantify nitrate impact potential to the underlying groundwater from percolating effluent and relate impact to the Porter-Cologne Water Act. This was accomplished by the referenced testing and loading calculations. • Ultimate wastewater flow volumes emanating from the proposed project have been estimated using all relevant and available resources, and specifically the EHD Sewage Standards. The nitrate loading calculations were formulated by using the number of people that will theoretically be on the subject property every business day,either partially, or for the entire work day. The soils testing and investigation has found the indigenous soils under the test location,which was near the northwest corner of the property, to contain a predominately sandy-silty material with rapid percolation rates down to approximately eight feet below grade. The perc rates are deemed acceptable in that they did not exceed 5 min/in. Perc rates faster than (below)5 min/in must incorporate design parameters during the construction of leachline trenches or filter beds. This would include using a two ft underlying liner material of silt, silty fine sand,or sandy clay to slow the permeability of the receiving soils and prevent saturated flow conditions. Although the test results show acceptable permeability throughout the subject soils, long-term acceptance rates of wastewater effluent by the indigenous soils will decrease over time primarily due to biomat formation. Hardpan strata was also encountered which may be beneficial in impeding nitrate formation and promoting denitrification. II. SOIL SUITABILITY STUDY FINDINGS A. SUBJECT PROPERTY AND SURROUNDING STUDY AREA INFORMATION SSS§ 1.1. As depicted on the Google Map aerial photograph found in Appendix A, surrounding land use to the north,east and south are almond orchards and other types of agricultural crop production. To the west is an industrial park with various types of businesses. All of these businesses are on individual septic systems with domestic water served by CSA-30. SSS§3.1,3.2,3.3,3.4,3.5,3.6,3.7,6.8. No Applications were on file at the EHD for permits issued for repairs/replacements/additions to existing septic systems within the one-half mile study area on Comconex Road or the 10000 block of Hwy 120. This can be attributed to the sandy soil structure of the surrounding soils. 2