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The 1997 reclamation areas sampled encompass approximately 18 acres of reclamation in <br />four distinct areas within the Keenesburg Mine permit area. The areas are found throughout <br />• the disturbance area of the mine and include Area 3 that is a road corridor between the <br />1985/1986 central reclamation areas and the 1986 east area, Area 14 (an area to the west of A <br />pit), and Areas 18 and 21, two areas adjacent to B pit. The 1997 reclamation areas are nearly <br />flat overall with a gentle slope (1-3°) to the north. Reclamation and coincident revegetation <br />with the permanent seed mix took place during the autumn of 1997 within these areas. <br />Replaced soils were sandy in texture. <br />Specific sampling information for the 1995 and 1997 reclamation areas is contained in Tables <br />1, 3, and 5. <br />3.1.2.1 Vegetation Cover <br />Total vegetation cover of the 1995 and 1997 reclamation areas was 61.40 percent (Table 3). <br />Graminoids provided 46.30 percent mean cover (77.62% relative cover), forbs accounted for <br />13.90 percent mean cover (19.60% relative cover), succulents provided 0.20 percent mean <br />cover and 0.40 percent relative cover, while one shrub contributed 1.00 percent mean and <br />2.38 percent relative cover. The lowest total vegetation cover of the 1995 and 1997 <br />reclamation areas sampled was found in Area 1 (44%) and the highest was in Area 3 (74%). <br />No single species was encountered in all the cover transects, though Sporobolus cryptandrus <br />was encountered in 95 percent of the transects. Calamovilfa longifolia was present in 85 <br />percent of all transects and Bouteloua gracilis was found in 80 percent of all transects. <br />• Bromus marginatus accounted for the highest overall vegetation cover in the 1995 and 1997 <br />reclamation areas with 12.30 percent mean cover and 17.35 percent relative cover. Nine <br />additional species contributed significantly to vegetation cover (greater than 3% relative <br />cover); Sporobolus cryptandrus with 7.80 percent mean cover and 12.98 percent relative <br />cover, Bouteloua gracilis contributed 5.40 percent mean cover (11.66% relative cover), <br />Calamovilfa longifolia provided 6.00 percent total vegetation cover and 9.27 percent relative <br />cover, Helianthus annuus accounted for 6.30 percent mean cover (8.87% relative cover), <br />Agropyron smithii contributed 4.40 percent total cover (7.68% relative cover), Bouteloua <br />curtipendula (sideoats grama) provided 2.50 percent mean total cover (5.43 percent relative <br />cover), Ambrosia psilostachya (ragweed) contributed 2.60 percent mean and 3.84 percent <br />relative cover, Bromus tectorum (cheatgrass), a cool season introduced graminoid, accounted <br />for 2.70 percent mean cover (3.58% relative cover), and Andropogon hallii contributed 1.60 <br />percent mean total cover and 3.18 percent relative cover. <br />Vegetative litter (prior years growth, dead wood, and other biologic organic material) <br />comprised 21.30 percent ground cover overall within the 1995 and 1997 reclamation areas. <br />Bare soil comprised 17.30 percent of the ground cover. No rock or cryptogams were <br />encountered during the cover sampling in the 1995 and 1997 reclamation areas. <br />3.1.2.2 Herbaceous Production <br />Overall mean total herbaceous production within the 1995 and 1997 reclamation areas was <br />• 229.27 g/m2 (2043 lb/ac). <br />Coors Energy Company Keenesburg Mine Page 11 <br />2007 Phase III Vegetation Study