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• WFC will monitor the sediment storage capacity of Pond 007 with one or a combination of the <br />following methods, as applicable: <br />1. Cross Sectioning or Grid Method -Since the sediment pond normally contains water <br />year round, a survey cross section or grid method will be used to determine <br />sediment volume using accepted engineering practices. The survey will be <br />performed on an annual basis to determine sediment storage capacity and to <br />determine when corrective action is required to restore adequate pond capacity. <br />2. Aerial Mapping - An alternative method is photogrammetric mapping that would <br />create an accurate 1"= 50' topographic map with 2 ft. contour intervals to determine <br />the remaining storage volume beneath the principal spillway. This method could be <br />used in conjunction with the surveyed cross section method. Once the topographic <br />map has been generated, accepted engineering methods will be utilized to perform <br />the volumetric calculations. <br />Corrective action required to restore adequate sediment storage capacity may include the following: <br />1. Raise the spillway and redesign the pond in order to restore adequate storage <br />. capacity and 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 in a stockpile used for reclamation. The <br />excavated material that is not suitable for atopsoil-like medium will be graded into the surrounding <br />topography within the disturbance area, topsoiled, and revegetated in accordance with WFC's <br />approved reclamation plan. Site specific conditions will determine the construction methods and <br />equipment utilized at the time of excavation. Sediment removal and water discharges will be <br />conducted consistent with the approved mining permit, the NPDES permit, and Section <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 CDMG. <br />Pit dewatering will be primarily a seasonal occurrence. The dewatering process will be a sporadic <br />operation-controlled, occurrence depending on various factors which may include the location of <br />the pit inflows, the location of standing water in the pit, or the location within the pit of the <br />overburden and coal removal operations. When pit dewatering is required, the anticipated <br />dewatering rate will be in the range of one to two cubic feet per second or less. Most dewatering <br />discharges will be directed to 007 East and West Ditches, which drains into Pond 007. However, <br />(REVISED 12100) 2.05.3(3) - 5 <br />