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to safely convey the peak discharge from the 100-year, 24-hour storm event in accordance with Rule 4.05.4. Since this is a permanent diversion draining a watershed greater than one square mile an as-built certification was provided for this channel The remaining twenty-two permanent channels are designed to safely convey the peak discharge from the 10-year, 24-hour storm event in accordance with 4.05.3 and do not require as-built certifications. Seneca Coal Company has permitted one ephemeral stream channel reconstruction on the reclaimed mine site; the Wolf Creek Fill Downdrain. The Wolf Creek Fill diversion ispermitted as arip-rapped trapezoidal channel with bottom width often feet and 3h:1 v side slopes. The downdrain was constructed in 1998 after the haul road ramp was reclaimed and no longer needed. This diversion diverts surface runoff away from the lower Wolf Creek Fill azea and is designed to convey the 100-yeaz, 24-hour storm event. Seneca Coal Company has twelve permitted stock ponds at the Seneca II Mine primarily for livestock grazing and secondarily as wildlife habitat. In February 2002 SCC submitted Technical Revision No. 35 to request approval for 12 stock ponds to be retained as permanent structures and also to request a waiver from the quarterly examination requirements for these ponds [Rule 4.05.9(18)]. In June 2003 all stock ponds were inspected to verify the adequacy of the safety demonstration required by 4.05.9(18) and to verify embankment heights and storage capacities (see inspection report dated 06/17/03). SCC has submitted letters from all appropriate landowners requesting that the stock ponds located within their property boundaries be left in place as permanent features. TR-35 was approved in August 2003 and the following stock ponds will remain as permanent features: T-4, T-8, T-16, T-17, T-20, T-26, T-28, T- 29, T-30, T-31, T-32, and T-33. The locations of the stock ponds are shown on Exhibit 7- 19and 13-2A of the PAP. C. Sedimentation Ponds Seneca Coal Company will primarily use sediment ponds to prevent additional contributions of sediment to streamflow or runoff outside the permit area due to mining disturbances. Existing sediment ponds include Wadge Impoundment (NPDES 002), Northwest Impoundment (NPDES 003), Pond 004 and Pond 008, PeCoCo Impoundment, Spill Control Pond #2, and Truck Wash Ponds. Information regarding the designs of the ponds and diversions is provided in Tab 7 of the permit application. Wadge Impoundment (002) A major portion of the Seneca II Mine is located within the Grassy Creek basin. Surface runoff originating in the western part of the permit area flows into Little Grassy Creek, a tributary of Grassy Creek. A large sediment pond, the Wadge Impoundment, is located neaz the mouth of Little Grassy Creek and controls runoff and sediment from a 2100 acre area. This pond was permitted as a permanent impoundment, and has been designed with a large permanent pool of 267 acre-feet. Runoff from the 10-year, 24-hour design storm is 12 acre-feet. Information in the ]4