2009-03-16_REVISION - C1981028 (4)

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Agropyron cristatum (crested wheatgrass), the introduced perennial range grass, contributed 1.73 percent total cover (3.68% relative cover), the cool season introduced annual grass • Bromus tectorum (cheatgrass) provided 2.53 percent mean total cover (3.33 percent relative cover), and the perennial native forb Ambrosia psilostachya (ragweed) accounted for 2.13 percent mean cover (3.16% relative cover). Vegetative litter (prior years growth, dead wood, and other biologic organic material) comprised 29.73 percent ground cover overall within the 1985, 1986, and 1987 reclamation areas. Bare soil comprised 7.07 percent of the ground cover. No rock or cryptogams were encountered during the cover sampling in the reclamation areas. 3.1.1.2 Herbaceous Production Total herbaceous production within the 1985, 1986, and 1987 reclamation areas (Table 4) in 2008 was 144.68 g/m2 (1290 lb/ac). 3.1.1.3 Species Composition Cover sampling identified four lifeforms and twenty-one species within the 1985, 1986, and 1987 reclamation areas. The lifeforms included eleven species of perennial grass, one annual grass, one perennial forb, one biennial forb, five annual forbs, one succulent, and one shrub. Of the species encountered on the 1985, 1986, and 1987 reclamation areas, fifteen were native and six were introduced. Perennial species outnumbered annual species by fourteen to six. Both warm and cool season species contributed to the seasonality of the 1985, 1986, and • 1987 reclamation areas. Warm season graminoids outnumbered cool season graminoids by seven to five. Cool season forbs prevailed by six to one. The succulent was evergreen and the shrub was deciduous. The 1985, 1986, and 1987 reclamation areas had eight species contributing greater than three percent relative cover this year. The species contributing greater than three percent relative cover included six perennial grasses, one annual grass, and one perennial forb. These species included Bromus marginatus (32.11%), Bouteloua gracilis (20.35%), Calamovilfa longifolia (11.40%), Andropogon hallii (7.19%), Sporobolus cryptandrus (5.61%), Agropyron cristatum (3.68%), Bromus tectorum (3.33%), and Ambrosia psilostachya (3.16%). 3.1.2 1995 AND 1997 RECLAMATION AREAS The 1995 reclamation areas encompass a total of approximately 36 acres of reclamation in six distinct areas within the Keenesburg Mine permit area. The areas are found throughout the disturbance area of the mine and include; Area 1 (the former tipple area north of the shop building), Area 8 comprising the east third of A pit, Area 24 (a road corridor from the northwest corner of the long term spoil storage area to the northwest boundary of the permit area), Area 26 (located south of the sediment pond), Area 27 (an area between the sediment pond and the 1985 reclamation area which was used for spoil storage), and Area 28, an area west of the sediment pond. The 1995 reclamation areas are nearly flat with a gentle slope • (<1 °) to the north and east. Coors Energy Company Keenesburg Mine Page 10 2006 Phase III Vegetation Study