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F al Leachfield Area inter months,hydraulic stress from rainfall may overload the drip irrigated disposal ore, 12100 foot long conventional leachlines are proposed to be installed south of osal field. In addition, if the drip field needs repair, replacing or becomes overloaded perational months, the effluent may be manually switched to the leachlines. Four distribution boxes will distribute the effluent among each of three leachlines. The pressurized effluent must come into a stilling basin before entering the distribution boxes to dissipate the energy of the effluent flow. An indexing valve will automatically switch between each distribution box. As indicated in Tables 1 and 2, the percolation rate at the 36-inch depth is at the transition of the clay type soil to the sandy silt soil, thus the observed slower perc rate of 45 mpi in comparison to the perc rate at the 42-inch depth of 21 mpi. Therefore, to take advantage of the finer grained soil to increase the denitrification potential, the leachline trenches should be approximately 36 to 40 inches in depth - directly above the clay/silt interface where a distinct color change is evident. The perc rate of 45 mpi translates to an application rate of 0.465 gals/ft Z/day. Taking into account the potential infiltrative surface area of each trench being one square foot on either side and two square feet at the bottom yields 4 ft' x 100 ft long trench x 12 trenches =4,800 ft'. Given the acceptance rate of 0.465 gals/ft/day x 4,800 ft' =2,232 gallons/day, which is approximately equal to the anticipated average daily flow of 2,475 gpd. Wastewater Disposal System Management Management of the wastewater disposal system will consist of several duties. First, the interceptor grease traps and the septic tanks will have to be periodically inspected for grease and scum build-up. Depending on use, the interceptor tanks may have to be pumped every six months to one year. Pump-out intervals for the septic tanks may be every two years. The drip irrigated disposal fields should be inspected on a daily basis during the spring and summer months. The effluent will not supply adequate irrigation water during these months of the year. Consequently, supplemental domestic irrigation water must be applied. During the daytime hours, the evapotranspiration potential must be taken full advantage of from the grass groundcover and soil surface. If the grass becomes water stressed, domestic well water must be applied carefully for short periods of time on hot and windy days. The rotation of effluent among the three subareas may be switched automatically or manually. Either method will require careful observations. If for some reason the entire drip disposal area becomes saturated, the effluent flow may be changed to the conventional leachlines. Nitrogen fertilization in the wastewater disposal area must be done with extreme care,preferably with slow release nitrogen. This also applies to the remaining landscaping throughout the Complex. Consideration may be given to taking soil samples and submitting them to a laboratory knowledgeable in assessing landscaping fertilization requirements. Page -22- Chesney Consulting