2009-03-16_REVISION - C1981028 (4)

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Cover sampling identified three lifeforms and 22 species within the 1995 and 1997 40 reclamation areas. The lifeforms included thirteen species of perennial graminoids, one annual grass, two perennial forbs, one biennial forb, four annual forbs, and one succulent. Of the species encountered on the 1995 and 1997 reclamation areas, sixteen were native and six were introduced. Perennial species outnumbered annual species by sixteen to five, with one biennial species. Warm season graminoid and forb species were more prevalent than cool season species (11 warm season to 10 cool season) in the 1995 and 1997 reclamation areas. Warm season graminoid species accounted for nine species and cool season grass species included five species. Five forb species were identified as cool season and two were warm season. The succulent was evergreen. The 1995 and 1997 reclamation areas had seven species contributing greater than three percent relative cover this year. These species included Calamovilfa longifolia (19.14% percent relative cover), Bromus marginatus and Sporobolus cryptandrus (18.60 percent relative cover each), Bouteloua gracilis (11.45%), Bouteloua curtipendula (7.16%), Agropyron smithii (6.44%), and Ambrosia psilostachya (3.94%). 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-47.01 S) and total herbaceous production (v=0.3749x2.24ss), or the established standard for species composition. Total Vegetation Cover (2008) Predictive Equation Value for 2008: 23.13% total vegetation cover (based on 7.95" precipitation value) Xbar S 1985/1986/1987 Rec. Areas 1995/1997 Rec. Areas 63.20% 59.20% 6.36 5.65 N 15 15 Nmin I 2 2 Based on the results of the 2008 quantitative sampling, the 1985, 1986, and 1987 reclamation areas and 1995 and 1997 reclamation areas significantly exceeded the predicted total cover vegetation value of 23.13 percent, meeting the final revegetation success criterion for vegetation cover. • Total Herbaceous Production (2008) Coors Energy Company Keenesburg Mine Page 12 2008 Phase III Vegetation Study