2009-03-16_REVISION - C1981028 (4)

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nearly flat with a gentle slope (<2°) to the north and east. Reclamation and coincident revegetation within this area took place in 1985. Replaced soils were sandy in texture. The • revegetation seed mix differed slightly in composition and representation of cool season grasses from the seed mix applied to the 1986 and 1987 reclaimed areas, yielding a slightly different species composition. The 1986 reclamation areas encompass approximately 51 acres of reclaimed pit in the central area of the Keenesburg Mine permit area. The 1986 reclamation area is composed of three parcels (Areas 4, 12, and 20) separated by north-south haul road corridors (Areas 3 and 19). The area is nearly flat with a gentle slope (<1 °) to the north and east. Reclamation and coincident revegetation within this area took place in 1986. Replaced soils were sandy in texture. The 1987 reclamation areas encompass approximately 39 acres of reclaimed pit and adjacent areas in the south central area of the Keenesburg Mine permit area. The 1987 reclamation area is composed of two parcels (Areas 11 and 17) separated by a north-south haul road corridor and three narrow reclamation parcels (Areas 9, 10, and 16). The entire 1987 reclamation area is nearly flat with a gentle slope (<1 °) to the south and east. Reclamation and subsequent revegetation within this area took place in 1987. Replaced soils were generally sandy in texture. Specific sampling information for the 1985, 1986, and 1987 reclamation areas is contained in Tables 1, 2, and 4. • 3.1.1.1 Vegetation Cover Total vegetation cover of the 1985, 1986, and 1987 reclamation areas was 63.20 percent. Graminoids provided 55.07 percent mean cover (87.19% relative cover) and forbs accounted for 5.87 percent mean cover (8.42% relative cover). Succulents accounted for 1.33 percent total cover (2.63% relative cover), while shrubs provided 0.93 percent vegetation cover (1.75% relative cover). The lowest total vegetation cover of the parcels sampled was found in Areas 12 and 17 (56%) and the highest cover (76%) was found in Area 11. No single species was encountered in all the cover transects, though Calamovilfa longifolia (prairie sandreed) and Bromus marginatus (mountain brome) were each encountered in 87 percent of the transects, Bouteloua gracilis (blue grama) in 80 percent of the transects, Sporobolus cryptandrus (sand dropseed) in 73 percent of transects, and Andropogon hallii (sand bluestem) in 53 percent of all transects. Bromus marginatus, a cool season native prairie grass, accounted for the highest overall vegetation cover with 21.20 percent mean cover and 32.11 percent relative cover in the 1985, 1986, and 1987 reclamation areas. Seven additional species contributed significantly to vegetation cover (greater than 3% relative cover); the warm season native perennial grass Bouteloua gracilis with 10.67 percent mean cover and 20.35 percent relative cover, the native warm season perennial grass Calamovilfa longifolia contributed 8.13 percent mean cover (11.40% relative cover), the warm season native Andropogon hallii provided 4.40 percent • total vegetation cover and 7.19 percent relative cover, warm season native graminoid Sporobolus cryptandrus accounted for 4.00 percent mean cover (5.61% relative cover), Coors Energy Company Keenesburg Mine Page 9 2008 Phase III Vegetation Study