Laserfiche WebLink
Pitch Reclamation Project Colorado Mined Land Reclamation Board — 2013 Annual Reclamation Report <br />Since 2002, slope stabilization measures have included planting of 1,100 lodgepole pines, and 200 <br />spruce seedlings on the contoured area and planting of 500 lodgepole pines and 200 Douglas fir <br />seedlings on the slopes opposite the constructed wetlands area. In 2006 and 2007, a significant number <br />of mortalities were observed among trees planted during previous seasons on the slope opposite the <br />constructed wetlands area. The dead trees were replaced with approximately 400 lodgepole seedlings. <br />The 2006 work included placement of several large rocks and rock material across the lower end of the <br />constructed wetlands area to further enhance sediment control and prevent previously placed tree slash <br />from washing out during thunderstorm events. In 2007, transplanting of cattails was undertaken on an <br />experimental basis. The relatively heavy snowpack in 2007 -2010 provided needed protection for the <br />cattails and many survived the past five years. From 2011 through 2013, additional cattails were planted <br />in the wetlands area from a source at a similar elevation. The wetland experiments will continue to be <br />monitored and enhanced where possible in 2014. <br />3.2 Tie Camp Creek Disposal Cell <br />In 2001 and 2002, dismantled building material from the former RTP, concrete and contaminated soils <br />removed from the immediate drainage, were removed and placed in a Disposal Cell near the toe of Tie <br />Camp Creek Low -Grade Stockpile. This cell was created in mid -1990 as a clay -lined repository for <br />materials dredged from the Sediment Control Pond. The cell, as shown on Figures 2 and 3, was left open <br />with sufficient capacity for the RTP demolition material. The demolition material and contaminated soil <br />placed in the cell were crushed and compacted. In 2003, the cell was shaped and prepared for the <br />placement of a clay cap. Placement and compaction of a clay cap was completed in 2004. A final layer <br />of topsoil (minimum 24 inches) was added and compacted on top of the clay cap during 2005. In 2007 <br />and 2008, finish grading was conducted on the topsoil cover to eliminate any low spots where water could <br />pond, and to enhance drainage on and around the disposal cell. Harrowing, scarifying and reseeding of <br />the surface of the disposal cell area were completed in 2007, 2008, 2009 and 2010 to improve the cover <br />stability and to minimize erosion. In 2011, the surface water drainage channel on the cell was repaired to <br />correct erosion issues noted during an inspection by the CDPHE. All repair and reclamation work was <br />conducted in accordance with an approved plan and conditions in the RML and the Pitch Reclamation <br />Project Procedures Manual. The completion report, dated September 19, 2011, was sent to and approved <br />by CDPHE and was included in the 2011 Reclamation report on a CD at the back of the report. The <br />repair work was monitoring closely in 2013 and appears to have corrected drainage and erosion issues. <br />3.3 Drainage and Erosion Control in the North and South pits and Waste 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 that 35 years ago. Problems had been exacerbated between 2007 and <br />2010 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 regraded as weather and ground conditions allowed to direct water to the "Spring Creek" <br />channel that flows on the 10,600 bench. The repair work was monitored closely in 2013 and broadcast <br />seeded. The repairs appear to have corrected the drainage and erosion issues. <br />As shown on photographs 4 & 5, straw bales were staked in place in late 2010 at the area above the pit <br />crest late to slow surface water velocities and reduce surface erosion. Visual inspection of the east wall <br />of the North Pit the past two years indicated that continued maintenance will be required, as expected, in <br />Pitch 2013 Reclamation Report 14April2014.Docx 5 <br />