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drained at a constant rate; however, the drainage was observed to shift from the south to north <br />tunnel and back again, appazently as a result of underground blockages. <br />Reclamation of the Rock Tunnel consisted of placing a four foot diameter Vylon (double walled <br />plastic) pipe into each mine entry. The pipe was bedded in a pea gravel bed, and fixed in place <br />using a low concrete footer at each mine entry. The northerly pipe extended out of the entry, and <br />tamed south to join the southerly pipe, which extends straight out of the entry. The outlet end of the <br />pipe is anchored to the ground by a concrete wall. A steel grate with a locking access door acts as a <br />barrier at the terminus of the pipe. A drainage ditch was constructed to convey the mine flow from <br />the pipe to the 016 treatment ponds located below the Rock Tunnel Waste Disposal Area. <br />The outlet portion of the pipes and the westerly portion of the entry highwall were backfilled to a <br />2.SH:1V slope. The backfill material was obtained by excavating anover-steeped fill slope located <br />adjacent to the North Fork of Dutch Creek. Subsequently, Mid Continent Resources constructed a <br />new channel to deliver the Rock Tunnel discharge directly to the North Fork of Dutch Creek, by- <br />passing the 016 pond system. This was done after receiving approval from the Colorado Water <br />Quality Control Division, the appropriate regulatory authority pertaining to water releases. <br />The remaining portion of the highwall adjacent to the now-backfilled Rock Tunnel entries was to be <br />backfilled, using the debris generated by demolition of the Lamphouse as a base. However, Mid <br />Continent Resources threatened a lawsuit if the Lamphouse was demolished. As a result, the <br />Division did not pursue demolition of the structure, and did not complete highwall backfilling. <br />The entire area was covered with approximately eight inches of dirt obtained from narrowing Road <br />B. The entire azea was also fertilized, seeded and mulched following completion of dirt work. <br />Dutch Creek <br />The Division applied for, and received, a grant from the Office of Surface Mining to replace the <br />problem-prone Dutch Creek flume with a permanent, naturally functioning channel. The new Dutch <br />Creek channel was designed and constructed so that it mimicked the stream chazacteristics of the <br />stream above the flume. The channel was constructed in the fall of 1998 to take advantage of low <br />flow conditions, and when completed, diverted the Dutch Creek flow upstream of the flume. <br />Pond Rec/amation <br />The pond reclamation project was designed to transform the sediment ponds on private and public <br />lands throughout the mine into maintenance free water retention structures, while providing benefits <br />to wildlife and other area values. All ponds a[ the site, excepting the 016 pond system which at the <br />time, treated the mine water dischazge, were subject to this project. <br />Coal Basin Mine Reduced Inspection Frequency September 10, 2007 <br />6 <br />