2011-02-28_REPORT - C1981028 (5)

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2.0 METHODS 0 2.1 SAMPLING DESIGN Prior to initiation of fieldwork, the permit document and applicable maps were reviewed to evaluate topography, reclamation timing, seed mixes, revegetation methods, management, and applicable revegetation standards. Numerical designations were assigned to the reclamation areas to eliminate confusion and facilitate future discussions in 2002. The numbers assigned to reclamation areas are depicted on the VegetationlRevegetation Map. Only those areas currently revegetated were assigned numbers, starting in the northeast corner of the permit area and proceeding clockwise through the site. As additional areas are reclaimed and revegetated they will be assigned numbers. A map of the mine site at 1:2400 scale (1 "=200') was used to delineate the revegetated areas (Coors Site Plan; Vegetation Sampling Locations). On a gridded overlay of the revegetation map, a Cartesian coordinate grid (50x50 feet) was established. Computer generated random numbers were used to establish a pool of x,y coordinates. Reclamation Area 30 contains 9.68 acres revegetated in 2006. In accordance with past monitoring, 10 vegetation cover transects and 15 total herbaceous production plots were quantitatively sampled in, 2010. Species composition data was derived from the total vegetation cover data taken by plant species. Sample sites were located in the field through compass triangulation and pacing from known landmarks. The Coors Energy Company VegetationlRevegetation Map (Appendix) illustrates a the location of the reclaimed areas and sample point locations. Reclamation Areas 2, 7, 10, 15, and 16 (1998 Reclamation Areas); Areas 5 and 9 (1999 Reclamation Areas); and Areas 6 and 19 (2000 Reclamation Areas) were quantitatively sampled this year in the second sampling of a two year sampling regimen in anticipation of a final bond release application for those areas in 2011. The results of those vegetation investigations are contained in a separate report. Reclamation Areas 25, 29, and 31 were qualitatively evaluated this season for total vegetation cover, total herbaceous production, and species composition. Coors Energy Company has been actively managing Area 25 in an effort to minimize cheatgrass growth and promote perennial graminoid growth this season. As this management has included mowing and herbicide treatments, it was concluded that quantitative sampling values might be skewed by such management efforts this season, and any quantitative sampling would be deferred until 2011. Reclamation Area 29 was included in the Phase H bond release request submitted early in 2010, and as this area would not be eligible for additional bond release until 2013, it is anticipated that any additional quantitative sampling will be deferred until 2012. Reclamation Area 31 was revegetated in 2009, with this year representing the second growing season. It is anticipated that quantitative monitoring will commence with the third growing season in 2011. The Keenesburg Mine 1985, 1986, and 1987 reclamation areas were monitored between 1994 and 1998, and subsequently released from Phase R liability in 1998 and Phase III liability in 2009 by CDRMS. The 1995 and 1997 reclamation areas at the mine were monitored between Coors Energy Company Keenesburg Mine Page 6 2010 Revegetation Monitoring Report