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CHLORIDE: Highly mobile within the soil and groundwater environments. Concentrations over 250 mg/1 can indicate pollution from septic systems. NITRATE: MCL of 45 mg/1 as nitrate (NO3) or 10 mg/1 as nitrate-nitrogen (NO3-N). ELECTRICAL CONDUCTIVITY: Measure of ions within the water. On the east border of the subject property exists an earthen canal operated by the South San Joaquin Irrigation District(SSJID). The canal is approximately twelve feet wide and seven feet deep. There was water flowing during our investigation at approximately six inches deep and two feet per second (fps), indicating sufficient slope for water transfer. This canal empties into the Delta Aqueduct. W. PROPOSED SEPTIC SYSTEM LOADING AND OPERATIONAL DESIGN The septic system to handle wastes from the proposed project was designed by Mr. Walter Curtis, C.E. His calculations can be referenced in the Appendix. In summary, a total disposal trench length of 1,200 feet will be needed based upon 3,500 gallons per day (or specific days of the week)of wastewater flow. Additionally, not only must the project maintain an elevation above the 100-year flood plain,there must also be at least a five-foot minimum distance maintained between _ the bottom of the leachlines and the highest anticipated depth to groundwater. This five-foot distance requirement provides an unsaturated vadose zone where high rates of biological, chemical and physical treatment of the wastewater can take place. In addition to estimating wastewater loading rates, climatic stress must also be considered regarding the loading of the septic system. Leachfields must transmit two hydraulic loads: the effluent load and the climatic load during the rainy season. The average yearly rainfall in the Tracy area is 12.50 inches which is significant enough to influence hydraulic loading. Future expansion of the Southwinds Church will of course, increase the effluent loading. However, it is difficult to predict the point at which maximum utilization of the Facility will be achieved, thus _ ensuring relatively constant wastewater flow rates. The soil that must be imported to achieve an elevation above the flood plain and create the necessary distance from leachline to groundwater depth must be of a specific classification for not only foundational purposes, but also for proper septic system operation. When soils with hydraulically limiting horizons, such as clays, are used for disposal, hydraulic stress occurs when the total effluent load plus infiltrated precipitation exceeds �- the transmission rate through the limiting horizon. During the rainy season, both climatic load and effluent load may have to be stored above this limiting horizon. 5 Naffey Ag Ppearch