2009-03-16_REVISION - C1981028 (4)

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L] Location Cover # of samples) Herb. Prod. # of samples) 1995 and 1997 Reclamation Areas Area] (7.4 ac.) 2 4 Area 3 (4.5 ac 1 2 Area 8 (8.1 ac.) 2 4 Area 14 (1.4 ac.) 0 1 Area 18 (8.6 ac.) 2 4 Area 21 (3.3 ac.) 1 2 Area 24 (10.5 ac.) 3 4 Area 26 5.6 ac. 2 2 Area 27 (3.1 ac.) 1 1 Area 28 (1.4 ac.) 1 1 Total Sam les 15 25 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 on 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. 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 as the second year of the required two years of quantitative sampling prior to seeking final bond release. 2.2 FIELD SAMPLING 2.2.1 Timing Field investigation was undertaken during the period September 25 through October 1, 2008. 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 2008 was far below normal, totaling only 5.47 inches of precipitation (January to July 2008). All months in 2008 showed significantly less precipitation than normal. Of the months used to assess growing season precipitation, only September and December 2007 had precipitation levels above average (150% and 129% respectively), due to early autumn rains and heavy December snow pack. Precipitation from January to July 2008 ranged from two percent (June 2008) to 100 percent (January 2008) below average. Cumulative precipitation between September 2007 and July 2008 was significantly less than average with a 27.2 percent deviation below the September-July average, and 56.4 percent below the annual precipitation average. Heavy precipitation late in September and December • 2007 did not provide adequate soil moisture through the late winter and into the 2008 growing season resulting in significantly lower growth from May through early August 2008. Coors Energy Company KeeneSburg Mine Page 6 2008 Phase III Vegetation Study