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density according to AASHTO Specification T99-74 or ASTM Test Designation D-898 in <br />~~ maximum 24intX1 lifts. Attached 'n Appendix A are resuRs of a Standard Proctor compaction <br />test IASTM D-898) performed an a sample of coal mine waate obtained from the Sanborn <br />Creek Mine. Since coal mine waste may be variabb in material properties, it is suggested that <br />coal mine waste placed in the waste bank be checked }or assuronu of proper placement in <br />regular intervals. <br />A dual purpose Somerset Cemetery road and waste bank haul road beginning in the existing <br />employee parking lot, at about EI. 8,090 h will climb at a 10 percent grads to the west as <br />shown on Drawing 95255-01 to El. 6,190 ft. Until the coal mine waste bank reaches EI. <br />8,190 it., waste will be transported to this elevation of the haul road, then dumped onto the <br />top surface of the existing waste bank bebw whero h will be spread and compacted in proper <br />lips to a 2 horizontal to vertical (2H:1 V) outer slope. At O. 8,100 ft, a 10•foot bench wi0 be <br />constricted for erosion control and stability. When the waste bank is constructed to the EI. <br />8,150 ft level, a 30•foot wide bench will traverse the waste. Coal mine waste will continue <br />to be end dumped from the haul road, then spread and compared until the waste is brought <br />to EI. 8,190 h. Another 30-foot bench will be constructed at EI. 8,200. Then, coal mine <br />~~ waste will be placed up to the ftrtal nest elevation of 8,240 h by constructing a portion of the <br />haul road on the coal mine waste bank. When the final crest elevation is reached, the crest <br />will be reclaimed and the final coal mine waste placed will fail in the haul road on the waste <br />bank. <br />4.1.2 Undsrdroin System <br />An underdrain system is a requirement according to Rule 4.10.3(1). Although them aro no <br />recorded springs within the draw, and diversions ditches wi0 be constructed upland that will <br />preverft the fbw of runoff water within the draw, an underdrain system has been developed <br />to ensure the full drainage of the coal mine waste bank. A detail of the underdrain is shown <br />in Drawings 95255-03. Borrow material suitable for use in the underdrain must be sand and <br />gravel with eobbbs and boukfers and bas than 5 percent fines. Calculations indicate that the <br />minimum pertneabt7fty regtirerrlertts for the material must be 1 centimeter per second (cm/sec) <br />or greater. Because of the large grained material used for underdrain construction, a <br />geosynthetic fiher must be placed between and coal mine waste. A 12 to 14 once per square <br />yard non-woven geofabric fiher will be placed between the coal waste and the underdrain. <br />96266/1424.Rf+T Coal Mina Waata Bank pnign for tM aanbom Creak Mkr <br />Oeto[iar 19ae WEBTEC, Inc. ~ <br />