2009-03-16_REVISION - C1981028 (4)

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• Location Cover # of samples Herb. Prod. (# of samples) 1995 and 1997 Reclamation Areas Areal (7.4 ac.) 3 5 Area 3 (4.5 ac.) 1 2 Area 8 (8.1 ac. 3 6 Area 14 (1.4 ac. 1 1 Area 18 (8.6 ac. 3 6 Area 21 (3.3 ac. 1 2 Area 24 (10.5 ac.) 4 6 Area 26 (5.6 ac. 2 4 Area 27 (3.1 ac. 1 2 Area 28 (1.4 ac.) 1 1 Total Sam les 20 35 11 Sample sites were located in the field through compass triangulation and pacing from known landmarks. Figure 1 illustrates the location of the reclaimed areas and sample point locations within each area sampled. The 1985, 1986, and 1987 areas were previously monitored (1994-1998) and after successfully meeting revegetation success criteria, were released from Phase II liability requirements by CDRMS August 11, 1998. The 1995 and 1997 areas were previously monitored (1998-2004) and after successfully meeting revegetation success standards a Phase II bond release was approved on June 15, 2006 by CDRMS. This year, as a precursor for application for Phase III bond release, the 1985, 1986, 1987, 1995 and 1997 areas were • quantitatively sampled for vegetation cover, total herbaceous production, and species composition. 2.2 FIELD SAMPLING 2.2.1 Timing Field investigation was undertaken during the period August 28 through August 31, 2007. This time period coincided with anthesis and maximum development of the majority of plant species found in the reclaimed areas at the mine site to be evaluated. Total annual precipitation at the mine in calendar year 2007 was above normal, attributable in part to 4.47 inches of precipitation received in May thundershowers. While precipitation at the mine was 55 percent below average in September 2006, October and December 2006 precipitation was 154 and 814 percent above average, largely due to the heavy snow pack from the December blizzard. Precipitation from January to April 2007 fluctuated above and below the average, while heavy precipitation in May was 198 percent above average. June precipitation was significantly lower than average, with July 2007 amounts slightly above average. Cumulative precipitation between September 2006 and July 2007 was significantly greater than average with a 34.8 percent deviation above the average. Heavy precipitation late in 2006 provided soil moisture through the late winter while heavy precipitation in May encouraged significant growth in both the annual grass and forb components at the mine. Significant annual sunflower growth was apparent in August 2007, with the native range and reclamation areas visually dominated by the yellow flowers. Coors Energy Company KeenesWrg Mine Page 6 2007 Phase III Vegetation Study