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Pitch Reclamation Project Colorado Mined Land Reclamation Board — 2014 Annual Reclamation Re <br />3.3 Drainage and Erosion Control in the North and South pits and Indian and Tie Camp <br />Rock Dumps <br />North Pit <br />Snowmelt, summer precipitation and springs in the east wall of the North Pit have been recurring issues <br />since the pit was developed more than 35 years ago. Problems were exacerbated between 2007, 2010 <br />and 2013 with heavier snow pack in the mine area. On the east wall of the North Pit, minor erosion in the <br />form of rill development had occurred between the 10,800 and 10,600 benches due to snow melt runoff. <br />This area, at the crest of the east wall of the North Pit, is a topographically low area that concentrates <br />surface drainage from a relatively large area above the crest of the east wall. In 2010 through 2012 the <br />area was re- graded as weather and ground conditions allowed to direct water to the "Spring" channel that <br />t <br />flows on the 10,600 bench. The repair work was monitored closely in 2013 and 2014 and reseeded using <br />fertilizer. The repairs appear to have corrected the drainage and erosion issues. <br />Erosion and drainage repairs on the east wall of the'North Pit over the past three years have been <br />effective. Maintenance was performed in 2010 due to displacement in the 10,600 bench coupled with <br />snow pack and precipitation causing ponding. The single pond developed in 2010 was graded and filled <br />to reestablish appropriate drainage on along the bench. As shown on photograph 8 & 9, in 2012 a <br />diversion ditch was constructed to channel water from the 10,800 bench to the 10,600 bench and on to <br />the "Spring" channel. Visual monitoring of this ditch confirmed that it continued to function effectively in <br />2014. 1 <br />The inlet to the North Pit Lake, shown on Photograph 10, shows gradual erosion channeling that has <br />occurred the past 12 years. No repair is deemed necessary at this time, but will be monitored closely in <br />2015 following the snow melt and summer precipitation.! <br />In 2013, UREA 46 -0 -0 fertilizer was applied on approximately 8 acres on the 10600 and 10800 benches <br />of the North Pit and Indian Rock Dump. Photographs 10, 11 and 12 show the increase in grass and forbs <br />