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Corrective action required to restore adequate sediment storage capacity may include the <br />following: <br />1. Raise the spillway and redesign the pond in order to restore adequate storage capacity and <br />to comply with the applicable regulations. <br />2. Excavate the pond area and enlarge the sediment storage capacity. <br />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 New Horizon's approved reclamation plan. Site specific conditions will determine the <br />construction methods and equipment utilized at the time of excavation. Sediment removal and <br />water discharges will be conducted consistent with the approved mining permit and Rule <br />4.05.6(3)(b). All sedimentation ponds will be inspected quarterly under the supervision of a <br />registered professional engineer and reported to the DRMS. <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. A new discharge point has been applied for to utilize the Pond 011 site. Actual water <br />flow velocity going into Pond 007 and Pond 011 will be controlled with adequate erosion control <br />(i.e., rock riprap, geotextiles, etc.) or discharged onto non -erodible bedrock material. This will <br />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 2.05.3(3)- <br />2. Pit dewatering will be sporadic versus continuous. The flow rate of one to two cubic feet per <br />second or less compared to the designed 10 -year, 24-hour peak inflow rate of 123.7 cubic feet <br />per second is very insignificant. In addition, pit water high in suspended solids will be allowed to <br />set for a period of time so the solids are allowed to settle out of the water and will remain in the <br />active pit area. Only after the pit water is clear, will it be pumped from the pit into Pond 007. <br />Furthermore, all discharge from Pond 007 will be in accordance with applicable discharge <br />permits. <br />Section 2.05.3(3) Page 5 February 2017 (TR -78) <br />