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The excavated material suitable for topsoil will be salvaged and used for reclamation. The <br />excavated material that is not suitable for a topsoil -like medium will be graded into the <br />surrounding topography within the disturbance area, topsoiled, and revegetated in accordance <br />with WFC's approved reclamation plan. Site specific conditions will determine the construction <br />methods and equipment utilized at the time of excavation. Sediment removal and water <br />discharges will be conducted consistent with the approved mining permit, the NPDES permit, <br />and CDRMS Regulations Section 4.05.6(3)(b). All sedimentation ponds will be inspected <br />quarterly under the supervision of a registered professional engineer and reported to the <br />CDRMS. <br />The revised NPDES Permit is enclosed in Attachment 2.05.3(3)-18. <br />Pit dewatering into Pond 007 was primarily a constant occurrence while mining was taking place <br />east of 2700 Road. The dewatering process was operation -controlled, depending on various <br />factors which may include the location of the pit inflows, the location of standing water in the <br />pit, or the location within the pit of the overburden and coal removal operations. When pit <br />dewatering was required, the anticipated dewatering rate was in the range of one to two cubic <br />feet per second or less. Once mining continued west of 2700 Road, Pond 011 will be used to <br />detain the pit pumping prior to discharge. At that time, Pond 007 will be somewhat over <br />designed. These procedures have been approved in WFC's NPDES Permit CO -0000213. A new <br />discharge point has been applied for to utilize the Pond 011 site. See Attachment 2.05.3(3)-18. <br />Actual water flow velocity going into Pond 007 and Pond 011 will be controlled with adequate <br />energy dissipaters (i.e., rock riprap, geotextiles, metal or concrete energy dissipater boxes, etc.) <br />or discharged onto non -erodible bedrock material. This will minimize erosion of the pond banks. <br />Updates and modifications to the mine pit dewatering plan are described in Section 2.05.3(3), <br />subsection 6. <br />Pit dewatering will have an insignificant impact on Pond 007, as shown in Attachment <br />2.05.3.(3)-2. Pit dewatering will be sporadic versus continuous. The flow rate of one to two <br />cubic feet per second or less compared to the designed 10 -year, 24-hour peak inflow rate of <br />123.7 cubic feet per second is very insignificant. In addition, pit water high in suspended solids <br />will be allowed to set for a period of time so the solids are allowed to settle out of the water and <br />will remain in the active pit area. Only after the pit water is clear, will it be pumped from the pit <br />into Pond 007. Furthermore, all discharge from Pond 007 will be in accordance with applicable <br />discharge permits. <br />Pond 007 will be maintained after reclamation as requested by the landowner. The demonstration <br />that this pond retention is in compliance with Rule 4.05.9(13) is included in Attachment <br />2.05.3(3)-16 Demonstration for Retention of Pond 007. <br />Page 2.05.3(3)-6 October 2015 (TR -69) <br />