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222222�� V. CONCLUSIONS Due to the unique configuration of the effluent disposal structure, Section 7.1 of the SJC OWTS Standards applies, which states: Engineered systems are non-standard systems uniquely designed for a specific location by a CA Registered Civil Engineer based on site specific information. Based on the failing rates of all three test borings and the use of the percolation rates obtained that were used to formulate an application rate, this project falls under the category of an engineered system. The nitrate loading calculations show the effluent from the proposed facility will theoretically possess a nitrate-nitrogen concentration of 1.7 mg/L NO3-N. The Federal nitrate Maximum Contaminant Level (MCL) is 10 ppm NO3-N. This comparatively low nitrate-nitrogen contribution by the proposed project can be attributed to the high denitrification capacity of the soil and comparatively large property area in correlation with wastewater ADF. According to Table 1.10.2 in the SJC Onsite Wastewater Treatment Systems Standards, the minimum soil depth from the floor of the effluent dispersal system to groundwater must be 8 ft based on the perc test results with regard to the filter bed elevation, and 10 ft below the bottom of a 25 ft seepage pit (35 ft). According to the groundwater maps, these separation distances are easily achievable since the groundwater is approximately 60 ft below grade. As referenced, it is imperative that the influent line draining at 2% fall from the Office Restrooms to the second (west) septic tank be installed as high in elevation as possible. An existing AT&T fiber optic cable is currently located at the north end of the 100%replacement area. This cable is to be relocated at the time of construction under the entrance driveway, approximately 100 ft north of the replacement area. A cap is to be placed on the two vertical perforated leachlines tees in each seepage pit and brought up to be accessible under a Christy or irrigation box. Standing effluent can be measured in each seepage pit if it accumulates in the distant future. Page -8- Chesney Engineering, Inc.