2010-03-18_REVISION - C1981035 (2)

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flow around the disturbed area of the mine surface facilities and return the flow to the native surface drainage channel below the mine bench. The ditches encircle the mine disturbance. One ditch conveys surface flow along the west side of the mine facilities to the native channel, while the corresponding ditch drains east and south above the mine portal and down the east side of the mine bench and surface facilities to the native channel. These open earthen channels will be sized to contain the precipitation events as required by regulation. The channels will be stabilized with a combination of vegetation and riprap (where necessary). SEDIMENT POND One sediment pond is planned for the King II Mine. The sediment pond is located at the southeast corner of the mine bench and sized to contain the precipitation events as required by regulation. Surface runoff will reach the sediment pond through a combination of sheet flow, berms, culverts and "V" ditches. Detailed plans, certifications and maps can be found in Appendix 11 and Maps King II-007, King II-007D, King II-007F and King II-007G. The pond contains a primary spillway at elevation 7233' and an emergency spillway at elevation 7234'. The spillways are both vertical 24" CMP risers with oil skimmers constructed as shown on Map King II-007F, Detail 1. The spillways are always open. The minimum magnitudes of storm events that will cause the spillways to discharge, subtracting a 60% sediment clean-out level of 1.5 acre feet, are as follows: Primary Spillway: 4.36 acre feet - 1.5 acre feet = 2.86 acre feet Emergency Spillway: 5.22 acre feet - 1.5 acre feet = 3.72 acre feet TOPSOIL Sufficient suitable topsoil resources exist in the Umbarg soil map unit to provide topsoil replacement depths of six inches. This replacement depth will require stockpiling and ultimate replacement of 16,133 cubic yards of topsoil from the A and B horizons of the Umbarg series. Topsoil will be salvaged and stockpiled using truck/shovel or scraper methods. Topsoil will be salvaged and stockpiled during the operation in piles constructed adjacent to the sediment pond and north of Coal Stack Tube #2. The topsoil pile will be stabilized using the seed mix proposed for final reclamation. To further minimize the potential for accidental contamination, a berm will be constructed around the perimeter of the toe of the topsoil piles. The berms will be of sufficient size (18" to 24" high, 4' to 6' wide) to prevent machinery from intruding on the topsoil stockpile. GCC Energy, LLC King II Mine Section 2.05.3 Page 6 March, 2010