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III. COMMENTS -COMPLIANCE <br />Below are comments on the inspection. The comments include discussion of observations made during the <br />inspection. Comments also describe any enforcement actions taken during the inspection and the facts or <br />evidence supporting the enforcement action. <br />This was a complete quarterly inspection of the reclaimed permit revocation site. Weather <br />conditions were clear and mild, and site conditions were dry. It was apparent, however, <br />that the site had experienced a major storm runoff event since the most recent inspection <br />conducted on July 29, 2003. Most likely, the runoff event occurred during early to mid <br />September, when there were a number of intense storm events in the general area. <br />Hydrologic Balance <br />The sediment pond was dry at the time of inspection, but several inches of new sediment <br />had been deposited in the pond since the previous inspection. There was apparent piping <br />erosion in the immediate vicinity of the base of the spillway riser pipe. Water may have <br />entered the discharge pipe through poor seals between the riser and outflow pipe, or around <br />the gated dewatering orifice, although this could not be determined with certainty. The <br />problem might be satisfactorily addressed by sealing the immediate area with bentonite. <br />This option will be pursued. <br />It appeared that maximum water level in the pond had been approximately 75 to 20 inches <br />high on the riser, above the original sediment level. <br />Along the reclaimed access road, there was minor rill erosion up to 6 inches deep in a <br />couple locations, and sediment up to an inch thick had been deposited in many of the track <br />hoe gouges along lower segments of the road. It was evident from water marks that the <br />gouges had puddled water 4 to 8 inches deep. There was evidence of significant flow <br />down the reclaimed channel that crosses the upper road segment in the former culvert <br />location. The flow was contained within the channel and the large sandstone riprap held up <br />well. The riprap had been extended across the load and down the outslope to a sandstone <br />outcrop below the road. There appeared to be some new erosion in the immediate vicinity <br />of the "plunge pool" below the outcrop, but significant headword erosion was prevented by <br />the outcrop. <br />There also was obviously heavy flow down the main reconstructed stream channel that <br />extends from the backfilled No. 1 portal slope across the relatively flat reclaimed top of the <br />No. 1 mine bench and down the extremely steep No. 1 mine bench outslope. Along the <br />upper, non riprapped segment of the channel on top of the mine bench, established shrubs <br />and grasses had been scoured from the channel, with channel incision 12 to 18 inches deep <br />in some locations. Large rock checks that had been imbedded in the channel held, and <br />appeared to function as designed. The steep riprap segment of the channel performed very <br />well, with no evident erosion or displacement of riprap. There was additional channel <br />incision in the 100 foot segment of the original stream channel down gradient from the toe <br />of the mine bench outslope. The channel in this segment was eroded to a depth of 4 to 5 <br />feet in some locations, averaging approximately 2 feet wide. Between the lower end of the <br />eroded segment and the sediment pond, there were intermittent areas of less severe incision <br />and deposition. In one of the depositional areas, water marks indicated a flow path <br />approximately 35 feet wide and a foot deep. <br /> <br />