2009-03-16_REVISION - C1981028 (4)

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3.1.2.3 Species Composition • Cover sampling identified four lifeforms and 30 species within the 1995 and 1997 reclamation areas. The lifeforms included fourteen species of perennial graminoids, one annual grass, four perennial forbs, one biennial forb, seven annual forbs, two succulents, and one shrub. Of the species encountered on the 1995 and 1997 reclamation areas, eighteen were native and twelve were introduced. Perennial species outnumbered annual species by twenty-one to eight, with one biennial species. Cool season graminoid and forb species were more prevalent than warm season species (17 cool season to 10 warm season) in the 1995 and 1997 reclamation areas. Warm season graminoid species accounted for eight species and cool season species included seven species. Ten forb species were identified as cool season and two were warm season. The succulents were evergreen and the shrub deciduous. The 1995 and 1997 reclamation areas had ten species contributing greater than three percent relative cover this year. These species included Bromus marginatus 17.35 percent relative cover, Sporobolus cryptandrus (12.98%), Bouteloua gracilis (11.66%), Calamovilfa longifolia (9.27%), Helianthus annuus (8.87%), Agropyron smithii (7.68%), Bouteloua curtipendula (5.43%), Ambrosia psilostachya (3.84%), Bromus tectorum (3.58%), and Andropogon hallii (3.18%). 3.3 COMPARISON OF RECLAMATION AREAS WITH FINAL REVEGETATION SUCCESS CRITERIA • Comparison of the reclaimed area values for vegetation cover, herbaceous production, and species composition with the final revegetation success criteria, indicates whether revegetation has been successful, or whether additional measures need to be initiated to enhance vegetation community development. The tables below allow the comparison of the parameter values with the standard to be achieved, either from the predictive equations in the case of total vegetation cover (y=0.0173x3-0.8592x2+14.562x-47.015) and total herbaceous production (y=0.3749x2.2485), or the established standard for species composition. Total Vegetation Cover (2007) Predictive Equation Value for 2007. 36.45% total vegetation cover (based on 15.00" precipitation value) 1985/1986/1987 Rec. Areas 1995/1997 Rec. Areas Xbar 60.80% 61.40% S 7.40 8.20 N 20 20 Nmin 4 5 Based on the results of the 2007 quantitative sampling, the 1985, 1986, and 1987 reclamation areas and 1995 and 1997 reclamation areas significantly exceeded the predicted total cover • vegetation value of 36.45 percent, meeting the final revegetation success criterion for vegetation cover. Coors Energy Company Keenesburg Mine Page 12 2007 Phase III Vegetation Study