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Please calculate pond discharges using four cases: low spoils spring flow with and without a 10-year, 24-hour event, and peak spoils flow with and without a 10-year, 24-hour event, (per the Eckman Park Permit, C-81-071, Revision 5, Pond F Modification, Table TR86-25). For your information, the Division predicted a peak spoils spring discharge of 0.41 cfs from Mine 3 into Fish Creek and a low spoils spring discharge of 0.12 cfs in the Foidel Creek Life-of-Mine Permit Revision Findings, Permit C-82-056. II, Soils - Rules 2.04,9, 2,05.3(5), 2,05.4(2)(d) and 4.06 The Fish Creek Tipple is a pre-law facility from which no topsoil was salvaged, Overburden is intended as the plant growth medium and the operator intends to amend the material as needed with nitrogen and phosphorus. The Division has re-evaluated the physical analyses of the overburden presented on page 2.04-37, and is concerned that the texture of the overburden will not provide an adequate base for vegetation re-establishment, as there is less than 7% soil-sized particles b~ weight. Wyoming guidelines for topsoil texture suggest that coarse fragments not exceed 35 percent by volume. The Division requests that Twentymile Coal Company develop alternative plans to improve the textural analysis of the plant growth medium. III. Backfilling and Grading - Rules 2,05.3(6)(b), 2.05,3(9), 2.05,4(2)(a), 2.05.4(2)(c), 2.09, 4,13 and 4.14 A. Twentymile Coal Company proposes to leave steep side slopes facing the railroad track and sediment pond. The Division requests that TCC revise the backfilling and regrading plan to lower these slopes to angles which blend better with the local topography and do not inhibit the post-mining land use of pastureland. In evaluating these post-mining topography plans, the Division will be looking for some swale areas which may be used to re-establish the drainage density. 1. Please provide two post-mining topography maps on a scale of 1"=200' with five foot (5') contour intervals of the initial backfilling and grading prior to re-seeding and the final backfilling and grading following pond removal. B. The Fish Creek Tipple reclamation plan was vague on a number of issues which are required to prepare the bonding calculations. Please submit responses for the following questions. Removal of stockpile feeders, the truck dump, conveyors, water spigot and lines and all other below ground facilities and mechanisms are not completely addressed in the reclamation plan and the bond calculations. Please revise Figures 14, 15 and 17 to show dimensions of all structures, describe their removal and prepare an appropriate bond calculation.