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49 <br />be found in Exhibit 37(1). <br />Compaction testing was conducted by CTL/Thompson, Inc. for the New Elk <br />Development Waste Pile (DWP) at approximately 3 -month intervals in June, <br />September, and November of 1995 and March of 1996. The results are included <br />in Exhibit 31 as documentation supporting a permit revision "Compaction Test <br />Results New Elk Mine Development Waste Pile CTL /Thompson job No. 22905 ". <br />CTL/Thompson observed pile conditions and excavated four test pits. The <br />results indicated that the waste dump was stable if compacted to at least 90% of <br />standard Proctor maximum dry density (ASTM D 698). A CTL/Thompson <br />evaluation at that same time of alternatives for the disposal of pond cleanings and <br />ditch cleaning material indicated that the materials could be disposed of on the <br />development waste pile provided they are adequately drained and compacted. <br />DWDA #2 is at full capacity in the year 2012. NECC needs a temporary <br />development waste pile (temporary DWDA) as a transition to DWDA #3, which <br />will be constructed at the West Mine area. The temporary DWDA pile will be <br />located north and east of the stockpiles shown on Map 11, Sheet 3. Development <br />waste will be stockpiled for at least 30 days, and until such time that final <br />approval is received for Technical Revision No. 65 (DWDA #3). Material will be <br />placed in two -foot lifts and compacted as stated above in reference to DWDA #2. <br />The new Development Waste Disposal Area #3 (DWDA #3) is planned for the <br />area west of the west mine fan. The storage capacity of the west pile is about <br />155,000 CY. Refer to Map 12 for the plan and profile sections of the proposed <br />DWDA #3. The overall pile height will be a maximum of 90 feet. Material will <br />be placed in up to 2 ft. lifts and compacted to achieve at least 90% of standard <br />Proctor maximum dry density (ASTM D 698). The pile will have 311: 1V side <br />slopes, and one 15' bench. The bench will slope back toward the pile at 2% and <br />to the runoff collection ditches at 2 -5 %. Design recommendations for the <br />DWDA #3 are included as Exhibit 43. The DWDA #3 will be constructed in <br />accordance with the design recommendations. <br />DWDA #3 is located over a historical mine structure referred to as a rail /rope <br />slope. Prior to placement of waste at DWDA #3, the rail slope will be <br />demolished in accordance with the recommendations included in Exhibit 43. <br />(9) Return of Coal Processing Waste to Abandoned Workings <br />The New Elk Mine Preparation Plant receives mined coal from the multiple <br />seams at the New Elk Mine. As the coal is washed, refuse is deposited in the <br />thickener, dewatered by the belt press, and sent by conveyor to the Refuse <br />Disposal Area (RDA). Handling of these fines has caused problems for the <br />operating efficiency of the Prep Plant. The operator is proposing to dispose of <br />these fines by pumping refuse /water slurry into the abandoned working areas of <br />Section 2.05 TR -68 12/10/2014 <br />