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Within the permit area 8,998,850 tons of coal will be recovered by the proposed oper- ation. Approximately 711,650 tons will be unrecoverable by this mining operation in areas identified in Chapter 11, Part D. XV. EXPLOSIVES (2.05.3(6)) The applicant has submitted a blasting plan, Volume 6, Section 3.2, detailing the types and approximate amounts of explosives to he used, control of maximum peak parti- cle velocity, the blasting wa ming and site access control procedure, and the unavoid- able hazardous conditions for which de viationS for the blasting schedule will be needed. The applicant has submitted a plan for recording the required information for each blast, and for submitting any pre-blast surveys to the Division. A copy of the blasting schedule has been published in the local ne::spaper. This section is in compliance with Rules 2.05.3(6) (~) and 9.08. XVZ. BACK FILLING AND GRADING (2.05.3(b), 2.05.3(9), 2.OS.9(2)(a) 2.05.4(2)(c), 9.09, 9.13, 4.19) Back filling and grading can be divided into two primary situations: The pits and other disturbed areas. [dhen overburden is removed from a pit by dragline or backhoe, back filling is accomplished by casting material into the adjacent, previously mined pit. Handling of the box-cut material and final cut represent special-handling situa- tions. In the Moffat Area, the hox-cut material will be spoiled down-hill, towards Trout Creek, where there is sufficient area and up-hill, away from Trout Creek, where the mining operation is close to Trout Creek. Valley. This will create an increase in the ground elevation in the area of the box-cut of up to 45 feet, and the slope towards the creek will be both increased and lengthened, but will not exceed Iv:3h (Exhibits 3.3-3 and 3.J-4). Rule 4.19.1(2)(4) of the Colorado Permanent Regulatory Program prohibits the permanent disposal of box-cut spoil outside of the mined area unless the material is not required to achieve approximate original contours. Zn addition, box-cut material :,•hich is not placed within the mined area is considered excess spoil and specific design and construction criteria are required by Rule 4.09.1 of the Colorado permanent regulatory program. These were not addressed by the applicant, but are applicable in those areas :;here the spoil is cast towards Trout Creek. Mining in the box-cut area of [~iest airlye has already been completed. 9. PRIOR TO DIu'TURB AiJCE I:V TlIF. FiOFFAT AREA, TFIE APPLICANT SFIALL SUB!dIT AND RECEIVE hFPROI%AL OF A PROPOSED PLAA! COPlCERNIIJG THE DGPtiSIT *~hV OF EXCESS SFOIL OUTSIDE OF TFFE MINED AREA. ADEn[J.ITE ANALYSES [JILh DE SnBMITTED TO DETERPIINE COMPLIANCE WITH PART 4.09 OF TFIE COLORADO PERMANENT REGULATORY PROGRA7-0, INCLUL ING, BUT NOT LIhfZTED TO, STADILIT1' APFA LYSES, CONSTRIJCTION DE'CAZCS' A7JD IIYDROLOGIC ASSESSMENT. within the final cut aceas of the Moffat Area the final pi.t will occur where the coal seam outcrops or in an area where up to 20 feet of overburden exists. 'C he final pit will be filled by grading tho spoil towards the final cut, and in the case where a highwall exists, the highwall will also be grdder] towards the final cut. The applicant analyzed the worst-case for each of these situations. Where the final pit daylights at the outcrop, the ground elevation will be decreased up to JO feet at the ridge top. However, due to the slope of the hi 11 side, positive drainage will still occur. (Exhibits 3.4-3 and 3.4-4). In the other situation, the yround elevation will be reduced approxi- mately 15 feet and large flat area approximately 100 feet along the slope in some areas will be created. Because this is Located at the ridge top, drainage will not: be a pro- blem. In the West Ridge Area, the applicant suhmit.ted a volumetric analysis For the final cut to determine if sufficient material was available to fill the c•ut. The Division concurs with the company's estimation that the material available is sufficient.