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• Soil chemical testing was conducted on three samples retrieved from the 25 foot percolation test boring which was also served as the exploratory test boring.'Physical testing of the soil included the J actual percolation testing to determine particle size analysis correlated with permeability. Chemical testing included analyses for the constituents that influence nitrate loading. The capacities of the on-site soils were analyzed for: 1.)The ability to accept anticipated future wastewater effluent flows, 2.)To assess the characteristics of the on-site soils to mitigate nitrate impact, and 3.) To quantify nitrate impact potential to the underlying groundwater from percolating effluent. This was accomplished by the referenced testing and loading calculations. • To fulfill the EHD requirement the on-site domestic well for+this project was sampled and analyzed for the specific constituents of nitrate and dibromochloropropane (DBCP). `JGwi • Wastewater flow volumes emanating from the proposed project have been formulated based upon �+ information provided by Mr. Zahi Haddad and by the San Joaquin County Sewage Standards. Therefore, the nitrate loading calculations are based on these flow volumes and associated criteria, which are found in Section III A of this Study. t The soils testing and investigation protocol has found the indigenous surface soils under the test locations, to contain a predominately fine-grained lean/fat clay material that has an extremely slow permeability. ��3 :Management of wastewater effluent by the surface soils down to 42 inches will only slightly occur as evidenced by the unacceptable percolation rates. Test results show a high degree of permeability in the deeper soils. From the surface down to seven feet is a lean-to-fat clay with a small volume of silty,very fine sand. From -7 to --17 ft is a fine sandy silt with some clay. From -17 to -24.5 ft is a silty fine sand. As noted,the soils begin acceptable permeability at approximately seven feet below grade. The soils at -7 to -17 ft below grade possess percolative capacity as demonstrated by an EHD unofficial percolation test I conducted at 8.5 ft below grade, representative of typical sump depth. The EHD official deep perc test at 24.5 ft also indicates very favorable percolation, representative of seepage pit depth. II. SOIL SUITABILITY STUDY FINDINGS A. SUBJECT PROPERTY AND SURROUNDING STUDY AREA INFORMATION SSS§ 1.1. Land use to the immediate north of the project is the defunct Bianchi Manor Country Residential Care Facility and farmland. To the east is also farmland and very low density housing. To the west is rural housing and the Highway 99/Eight Mile Road interchange and Frontage Road. South of the project is rural thousing and a mobile home park. The land use referenced is illustrated on the San Joaquin County Parcel Viewer Maps found in Appendix A. r SSS§3.1,3.2,3.3,3.4,3.5,3.6,3.7,6.8. Applications on microfiche files with the EHD reveal that there } have been nine permits issued for repairs/replacements/additions to existing systems within the one-half % mile radius study area on Eight Mile Road exclusively. This can be considered a very high number of , permits for the study area and definitely indicates marginal soil permeability in the shallow surface soils, �a characteristic of the Morada area. From observations made by EHD, commercial facilities on conventional septic systems along and near the Highway 99 Corridor, particularly in the Morada area,have been problematic. However, given that the deeper soils under the project illustrate excellent permeability, effluent management for the St. Sharbel project should not pose a problem. 2 Chesney Consulting