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AGGREGATE ABSORPTION AREA (A) A = 1,440 f 2 (8 ft wide x 180 ft long) MOUND DEPTHS Washed Sand = 12 in. Aggregate Absorption Area thickness =9 in. (6 in. of aggregate below the laterals, 1 in. for pipe height and 2 in. for cover over pipe = 9 inches) Thickness of Topsoil = 8 in. Cap over Aggregate Absorption Area = 12 in OVERALL BASAL AREA: LENGTH AND WIDTH (L x W) L = 200 ft N-S W=30 ftE-W Area = 6000 ft2 SOH, COVER The soil cap and soil cover must consist of a silt loam material to allow oxygen diffusion into the mound system (USCS = m1). This will entail importing silt loam material since onsite material is clay. The mound slopes will not exceed 5:1, which will place the height of the mound at approximately 2.75 feet higher than surrounding grade. Natural or planted grass vegetation must be allowed to grow on this soil cap to maintain soil stability. REPLACEMENT/RESERVE AREAS Because the mound system footprints for the two proposed residential structures envelop significant area, insufficient replacement area exists. Therefore, when the primary systems fail (indicative of surfacing sewage), the only alternative is to remove them and construct new mound systems over the existing footprints. It is anticipated that the primary mound systems have an approximate two decades long lifespan provided that the entire system is monitored and maintained on a yearly schedule. Regarding setbacks for the subject Parcel, there is a distance of 104 ft from the east property line to the toe of the existing building pad embankment for the north building pad. For a fill bank, the disposal area must not encroach within 4 times the vertical ht of the fill bank, as measured from the top edge of the bank. The building pad is 10 ft high; therefore, measuring from the top edge of the bank: 4 x 10 = 40 ft minus 18 ft (embankment horizontal distance) =22 ft from the toe of the embankment. As illustrated on the design plans, there is sufficient setback distance for both building pads on the subject Parcel. D. MOUND SYSTEM OPERATIONAL COMPONENTS CONFIGURATION OF PRESSURE DISTRIBUTION NETWORK The distribution piping (laterals) will discharge the effluent uniformly over the drain rock bed, with orifices spread five-foot apart so that effluent application area is -5 fe/orifice. Force main (transport line) piping will directly connect to the two laterals. The two laterals are to be 4 ft apart. Orifices shall be drilled with a new 7/64" dia. drill. A squirt test should then be conducted, and if sufficient for 5 ft of distal head pressure at the ends of each lateral, re-drill each orifice to 1/8" dia. Orifices are to be installed facing up, with orifice shields connected. Clean-outs at the distal ends of the two laterals will extend upward with long-sweep turn-ups with control valves. These clean-outs are to be placed within access boxes, as described on the design plans. 10 Chesney Consulting