1995-08-18_GENERAL DOCUMENTS - C1981041

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seeded bench, and, unless delayed by seepage there would be no more than two completed benches between the active disposal and the most recently covered bench. 3 ) Soil will be salvaged from the CRDA No. 3 area, CBA No. 1 , CBA No. 2 , and one or more of several other tentatively identified borrow areas. Sampling will be done prior to excavation, with a minimum of 1 sample/acre at 2 foot depth intervals. Topsoil piles will also be sampled prior to redistribution. 6" topdressing layer is to have an SAR<12, and EC<8mhos, cover below 6" depth will not exceed SAR of 25, and EC of 15mhos. The cover letter to the revision approval states that " . . .Powderhorn needs to receive Division approval for utilization of these locations and material through the usual revision process. " 4 ) The revision also set forth a quantitative vegetation monitoring plan to be implemented on final reclaimed areas during the second, fourth, and sixth growing seasons, with annual qualitative visual inspection of final vegetated stands to be conducted throughout the period of responsibility. TR 17 proposed approval decision was issued April 19, 1994. The revision established two borrow areas for refuse cover material (CBA #1 and CBA #2) , and allowed for the initial phase construction of Sediment Pond #11 . Prior to activation of CRDA No. 3 , pond enlargement will be required. Important aspects of the revision include the following: 1 ) Projection that 30,000 yards of cover material could be obtained from CBA #1 , and 65,000 yards of cover from CBA #2. Some sample data was submitted, with commitment to provide additional sample analyses prior to distribution of material on the refuse piles. Preliminary sampling indicated potential soil quality limitations due to high SAR values. Reclamation plan for borrow areas was defined. 2) Sediment control designs for the two borrow areas, including Sediment Pond 11 , SAE sumps, silt fencing, riprapped channels, and vegetative stabilization were provided. Construction of Upper Coal Canyon permanent channel diversion associated with CRDA #3 is not to be implemented in association with TR 17. TR 18 proposed approval decision was issued October 13 , 1994 . The revision allows for reactivation of CRDA No. 1 , based on the results of a stability analysis completed on the pile, and includes a commitment to monitor water levels within 30 piezometers installed on the pile on a quarterly basis, and implement corrective measures if defined critical water levels are exceeded. The revision also sets forth additional ground water monitoring requirements for the Unit Train Loadout and provides for a new minewater discharge point (015) at the 2 West Portals.