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FrDetention Time= 6.6 days. The minimum acceptable detention time is 1.0 day. Therefore, the posed 1,200 gallon septic tank is sufficient volume. OPERATIONS AND MAINTENANCE PLAN 1. Fixtures should be checked in each restroom to insure there is no leakage. This should be done on a weekly basis. 2. After two years of operation, the septic tank should be inspected by a qualified professional to determine if the tank should be pumped. 3. Only shallow rooted plants/shrubs, or a grass should be planted in the landscape area to prevent root intrusion into the perforated leachline pipe. Additionally, some plants are sensitive to the ammonium in septic effluent which may cause the plants to die. V. CONCLUSIONS The percolation testing revealed an anomaly for the 36" deep test boring. The entire refill water volume seeped away every 30 minute interval. In comparison, the 42" deep boring perc test result of 7.4 min/in was more plausible for this soil type. It is assumed the 36" test boring was drilled into a soil anomaly or a rodent excavation. Considering the leachline floor area of 2 ft x 100 ft= 200 ftZ x the application rate of the 42" test boring of 0.80 gals/ft2/day= 160 gpd. Therefore, the leachline can theoretically manage 160 gpd. According to Table 1.10.2 in the SJC Onsite Wastewater Treatment Systems Standards, the minimum soil depth from the bottom of the effluent dispersal system to groundwater must be 8 ft based on the 42" perc rate test result. The Depth to Groundwater maps indicate this separation distance is easily achieved since the groundwater is greater than 8 ft below grade. The nitrate loading calculations show the effluent from the proposed facility will theoretically possess a nitrate-nitrogen concentration of 1.9 mg/L NO3-N. The Federal nitrate Maximum Contaminant Level (MCL) is 10 ppm NO3-N. This low nitrate-nitrogen contribution by the proposed Restroom project can be attributed to the denitrification capacity of the soil and the comparatively large property area in correlation with wastewater ADF. Only Parcel 13 at 3.9 acres was used in the calculations and not the entire acreage of the Cemetery at 9.94 acres Considering that Parcel 13 was intermittently farmed, in addition to the surrounding area which has been farmed for decades, there is a potential for nitrate contamination to the underlying groundwater from nitrogen fertilizer applications, residual organic matter decomposition, and OWTSs. This was evidenced by the onsite well water test results found in Appendix E, which where slightly over the Maximum Contaminant Level (MCL) at 10.3 ppm NO3-N. DBCP was non-detect(ND). Page -6- Chesney Engineering, Inc.