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-~- XVII. Backfillinq and Grading - Rules 2.05.3(6), 2.05.3(9 Rule 2.05.3(6) - Overburden 1. The amended application briefly states that it has been the operator's experience during the mining of pits 1 through 3, under the interim program permit, that overburden swell has regularly equalled the amount of material removed as coal. The operator projects a swell factor of approximately 15Y,. balanced by coal extraction, resulting in an overall bulkiny factor of 1.0. The applicant should verify this conclusion regarding projected bulking. This demonstration could take the fonn of a comparison of pre-mining and post-mining surveyed topography of the completed pits at the Grassy Creek mine. The applicant should include a material movement and balance discussion, in order to confirm that this comparison considers the final disposition of all materials originally extracted from the pits. 2. The application mentions that temporary overburden stockpiles are developed to store overburden from the pits during extraction. In accordance with Rule 2.05.3(6), the applicant must describe, at a minimum, the location, geometry and method of placement of these overburden stockpiles. Considering the steep slopes encountered throughout the Grassy Creek mine site, the operator should describe the selection of sites and the preparation of the foundation of the various piles in order to demonstrate that they will be stable during their temporary life span. Appropriate discussion of the reclamation of the stockpile sites should also be included within the appropriate reclamation plan sections of the amended application. Rule 2.05.4(2)(c) - Backfilling and Grading The applicant comments, on page IV-5 of the amended application document, that auger mining pits No. 6, IJo. 7, and No. 8 will be backfilled in a configuration which varies from the pre-mining topography. Schematic cross-sections of a typical auger area are presented in Figure 1 of Section 2.06.9, page V-16 of the amended application. Tne applicant should include this cross-reference within the text of Rule 2.05.4. In addition, the applicant should expand the rather vayue and ambiguous statement concerniny final topography of the angered pit areas. The applicant should specifically discuss why the confiyuration proposed in Fiyure 1 of Section 2.06.9 constitutes the reconstruction of approximate original contour.