PERMFILE106535 - Laserfiche WebLink

Home Browse Search

Construction of the Portal Area sediment pond began immediately after the Scullion Gulch diversion pipe installation was completed above the pond location. The installation of the diversion and sediment pond was completed within 6 months after construction work began. When construction began, it was determined that suitable clay materials for construction of the Portal Area sediment pond could not be found in the Portal Area, suitable clay material was imported from areas to be disturbed in the Refuse Disposal Area. All material borrowed from the Refuse Area was replaced with material from the "D" Portal Area that is suitable for use as nontoxic fill material. To control sediment from the disturbed "D" Portal Area which might have been carried down Scullion Gulch during the first summer of construction, a series of three loose rock check dams were constructed in the Scullion Gulch stream bed below the sediment pond location. The dams are approximately 100 feet apart and the spillway bottoms are approximately two feet high above the stream bed. These rock check dams are shown on Map 32. The layout of the ponds andlor ditches are presented on Maps 24, 25, 26 and 27, ("D" Portal), Maps 103 and 114 (Railroad Loading Area), Map 89 (East Portal), Map 77 and Map 77A (Refuse Disposal Area). Pond details are presented on Maps 34, 35, 78, 79, 80 and 80A. IV.J.3 Operation and Maintenance During the mine life, all sedimentation and drainage facilities will . be inspected regularly, cleaned and maintained as required. The ponds will be cleaned and the sediment disposed of in the Refuse Area along with coal processing waste. The sediment level will be checked quarterly during normal inspections. An NPDES discharge permit was obtained for each of the sedimentation ponds, with monitoring of the pond discharge proceeding in accordance with the appropriate permit. Copies of the NPDES perrnit for the sedimentation ponds are contained in Illustration 13. If not already required by the NPDES permit, suspended solids, total iron, total manganese, total dissolved solids, pH, and flow rate have been added to the list of parameters to be sampled to meet the requirements of OSM and DMG. The pH of the water is greater than 6.0. However, if the pH falls below 6.0, a neutralizing process will be installed, operated and maintained. Because of infrequent flows, the method used, if required, wilt be manually operated unless otherwise directed. Sedimentation and drainage control facilities for an area will be maintained and operated until the area has been restored and revegetated and reclamation has been determined successful by the appropriate agency, An exemption was requested from the requirement to maintain and operate Sediment Pond DP-1 until final reclamation and revegetation has been determined successful. It is not possible to leave this pond . Mine Permit Renewal #3 (Rev. 11/99) IV-40