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Pitch Reclamation Project Colorado Mined Land Reclamation Board — 2012 Annual Reclamation Report were observed among trees planted during previous seasons on the slope opposite the constructed wetlands area. The dead trees were replaced with approximately 400 lodgepole seedlings. The 2006 work included placement of several large rocks and rock material across the lower end of the constructed wetlands area to further enhance sediment control and prevent previously placed tree slash from washing out during thunderstorm events. In 2007, transplanting of cattails was undertaken on an experimental basis. The heavy snowpack in 2007 -2010 provided needed protection for the cattails and many survived the past five years. In 2011 and 2012, additional cattails were planted in the wetlands area from a source at a similar elevation. The success of the experiment will continue to be monitored and enhanced in 2013. 3.2 Tie Camp Creek Disposal Cell In 2001 and 2002, dismantled building material from the former RTP, concrete and contaminated soils removed from the immediate drainage, were removed and placed in a Disposal Cell near the toe of Tie Camp Creek Low -Grade Stockpile. This cell was created in mid -1990 as a clay -lined repository for materials dredged from the Sediment Control Pond. The cell, as shown on Figures 2 and 3, was left open with sufficient capacity for the RTP demolition material. The demolition material and contaminated soil placed in the cell were crushed and compacted. In 2003, the cell was shaped and prepared for the placement of a clay cap. Placement and compaction of a clay cap was completed in 2004. A final layer of topsoil (minimum 24 inches) was added and compacted on top of the clay cap during 2005. In 2007 and 2008, finish grading was conducted on the topsoil cover to eliminate any low spots where water could pond, and to enhance drainage on and around the disposal cell. Harrowing, scarifying and reseeding of the surface of the disposal cell area were completed in 2007, 2008, 2009 and 2010 to improve the cover stability and to minimize erosion. In 2011, the surface water drainage channel on the cell was repaired to correct erosion issues noted during an inspection by the CDPHE in August 30, 2011. All repair and reclamation work was conducted in accordance with an approved plan and conditions in the RML and the Pitch Reclamation Project Procedures Manual. A copy of the completion report, dated September 19, 2011, was sent to and approved by CDPHE and was included in the 2011 Reclamation report on a CD at the back of the report. The repair work was monitoring closely in 2012 and appears to have corrected the drainage and erosion issues. 3.3 Drainage and Erosion Control in the North and South pits and Waste Rock dumps North Pit Snowmelt, summer precipitation and springs in the east wall of the North Pit have been recurring issues since the pit was developed. This problem had been exacerbated between 2007 and 2010 with heavier snow pack in the mine area. On the east wall of the North Pit, minor erosion in the form of rill development had occurred between the 10,800 and 10,600 benches due to snow melt runoff. This area at the crest of the east wall of the North Pit is a topographically low area that concentrates surface drainage from a relatively large area above the crest of the east wall. In 2010, 2011 and 2012 the area was regraded as weather and ground conditions allowed to direct water to the "Spring Creek" channel that flows on the 10,600 bench. As shown on photographs 2 & 3, straw bales were staked in place in late 2010 at the area above the pit crest late to slow surface water velocities and reduce surface erosion. Visual inspection of the east wall of the North Pit in 2012 indicated that continued maintenance will be required, as expected, in the two locations where an expression of the Chester Fault system, commonly referred to as the "smile crack" crosses the 10,600 bench. The displacement has created "cracks" or "steps" in the 10,600 bench that require re- grading periodically. Also, depending on the level of snow pack and summer precipitation, every few years one or two small ponds form along the 10,600 bench. During 2010, the single pond that had developed on the 10,600 bench was graded and the bench surface was filled and smoothed to re- Pitch 2012 Reclamation Report 04-16-13 Doc 4