2009-10-13_PERMIT FILE - C1991078A (3)

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2.05.4(2)(b) • In round numbers the amount of material, measured in cubic yards, that will be handled to reclaim the mine at the worst case condition is as foll ows: Topsoil Spoil Spoil Spoil From From From From Highwall Stockpile Stockpile Ridges Reduction Area 1 25,000 81,000 56,000 -0- Area 2 75,000 20,000 58,000 89,000 Pond B 14,000 • The 25,000 cubic yards of topsoil in Area 1 repre- sents 18.6 acres of untopsoiled area using the 10 inch topsoil replacement depth. In Mining Area 2 the topsoil replacement depth is 20 inches. The 75,000 cubic yards of topsoil in Area 2 therefore represents 27.9 acres of untopsoiled area. The topsoil in the Pond B area is just that topsoil salvaged during the Pond B construction which represents a disturbed area of about 3 acres. The total area to be topsoiled and reclaimed in this analysis is (18.6 + 27.9 + 3) 49.5 acres. The haul distances for the spoil and topsoil from the stockpiles and the average grade for both are as follows: Topsoil Spoil Topsoil Spoil Topsoi Haul Distance 2400' 900' 3600' 3000' 300' 1 Grade 2.28 2.98 2.78 2.58 -6.78 The following discussion forms the basis for the above reclamation estimate: Spoil and Topsoil It will be assumed that an equipment spread of two 651E scrapers and one D-9 push cat will be used to haul the spoil and topsoil. Cycle times and productions are as follows. The CY/Hour production figure assumes two scrapers, a 50 minute work hour, a payload of 34.6 cubic yards of topsoil and 34.6 cubic yards of spoil. The cost per cubic yard is calculated using an hourly rate of $150 for the D-9 and $175 for the 651E scrapers. Load/Dump Haul Return Total CY/Hour Cost/CY Topsoil Area 1 1.3 1.6 1.0 3.9 444 1.13 Spoil Area 1 1.3 0.6 0.5 2.4 721 0.69 Topsoil Area 2 1.3 2.2 1.4 4.9 353 1.42 Spoil Area 2 1.3 1.8 1.2 4.3 402 1.24 • 2.05-17i May 1992