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TABLE 1 SOIL PROFILE DEPTH I UNIFIED SOIL CLASSIFICATION SYSTEM - USCS 0 - 5 FT BELOW GRADE FINE SANDY LOAM - SM 6-11 FT BELOW GRADE CEMENTED SILTS HARDPAN - CL/ML 11 - 15 FT BELOW GRADE SILTY CLAY - ML/CL 15 - 24 FT BELOW GRADE DENSE SILTY SAND AND GRAVEL - SM/GM TABLE 2 PERCOLATION TEST RESULTS WITH CORRESPONDING APPLICATION RATES IN GALLONS I FT'/ DAY 36 INCH DEEP PERC TEST 35.7 min/inch / 0.467 gallons/ft2/day 42 INCH DEEP PERC TEST 27.8 min/inch / 0.556 gallons/ft2/day 288 INCH (24 FT) DEEP PERC TEST 17.9 min/inch / 0.686 gallons/ft2/day Application Rates adapted from Waste Quality Control for Siting, Design, Operation and Maintenance of On-site Wastewater Treatment Systems, based.on the Perc Rate. Due to the encountered cemented silts hardpan from 6 to 11 ft below grade and the average perc rates obtained for the shallow tests, it is prudent to install two - 3 ft diameter x 25 ft deep seepage pits that connect to the filter bed through tightlines, as illustrated on the attached OWTS conceptual design (Appendix E). The filter bed soils will manage the effluent flows until severe biomat formation may cause the transfer of a percentage of effluent volume to flow to the seepage pits. As noted, the primary and 100% reserve/replacement areas are illustrated on the Aerial Photo located in Appendix E. The OWTS will operate as follows: Blackwater and graywater will gravity flow into a P&L Concrete 2,000 gallon, two compartment, standard precast septic tank. If the septic tank is installed in an area where it may be parked on or driven over, it must be traffic rated. A Polyloke PL68 Effluent Filter shall be installed on the tank outlet. Septic tank effluent will then gravity flow to a 4-hole Tuf-Titeg distribution box (D-Box) situated within the filter bed to be equally divided between three - 25 ft long perforated leachlines, spaced six ft apart. The ends of the leachlines are to be manifolded together. Two - 4" dia. tightlines connect to the manifold and then connect to the vertical, perforated pipe in the two 3 ft diameter x 25 ft deep seepage pits. The two tightlines connected to the manifold shall be elevated 4" above the top of the manifold, as all illustrated in the conceptual design. The 100% reserve area is denoted approximately 250 ft north of the primary disposal area. The reserve area would be constructed exclusively as a 1,350 sf filter bed, with no seepage pits. Upon activation of the reserve area, a duplex pump system must be installed in the second compartment of the septic tank and the effluent pumped to this location. Page -4- Chesney Consulting