2011-02-28_REPORT - C1981028 (5)

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3.2 QUALITATIVE EVALUATION: RECLAMATION AREAS 25, 29, AND 31 Qualitative assessments of total vegetation cover, total herbaceous production, and dominant individual species present were made within Reclamation Areas 25, 29, and 31 in 2010. Reclamation Area 25, first reclaimed in 1995 and reseeded in 2002, comprises 12.64 acres immediately east of the long term spoil area; total vegetation cover was estimated at 45-50 percent this season. Total herbaceous production was estimated to be 130 grams/m2. The dominant species within the parcel was Bromus tectorum. The subdominant species was Calamovilfa longifolia. Additional species observed with moderate frequency were Panicum virgatum (switchgrass), Lactuca serriola (prickly lettuce), and Andropogon halhi (sand bluestem). The west, south, and east boundaries of this parcel exhibited better perennial grass growth this season than did the center of the parcel. Coors Energy Company is managing this parcel through mowing and pre-emergent herbicide treatment to minimize annual grass dominance. Reclamation Area 29 vegetation cover was estimated at 50 percent cover this season. This area contains 8.1 acres, was revegetated in 2003, and is located at the south boundary of the reclaimed B Pit. Total herbaceous production was estimated at 150 grams/m2 this season. There was uniform perennial vegetation cover on this parcel this season, with a mix of warm season perennial graminoids, forbs, and shrubs, including; Calamovilfa longifolia, Andropogon halls, Bouteloua gracilis, Ratibida column fera (prairie coneflower), Lactuca serriola, Nuttallia nuda (shooting star), Bouteloua curtipendula (sideoats grama), Panicum virgatum, and Artemisia filifolia (sand sage). Reclamation Area 31 comprises 11.92 acres that were revegetated in 2009. This parcel is largely located in the area of the reclaimed B Pit. Vegetation cover was estimated at 25 percent this season, and total herbaceous production was estimated at 75 grams/m2 this season. The dominant species in this second season growth are Conyaa canadensis (horseweed), Mehlotus of cinalis, and Calamovilfa longifolia. 3.3 COMPARISON OF RECLAMATION AREA 30 WITH FINAL REVEGETATION SUCCESS CRITERIA Monitoring of revegetated areas at reclaimed coal mines allows for the identification of vegetation community development trends during the extended liability period. This evaluation also assists in decisions regarding yearly grazing, husbandry practices, interseeding, fertilizing, and weed management. 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 implemented to enhance revegetation community development. The table below allows the comparison of the parameter values with the standard to be achieved, either from the predictive equations in the case of vegetation cover (v=0.0173x3-0.8592x2 +14.562x- 47.015) and herbaceous production (v=0.3749x2.2485), or the established standard for species composition. C7 Coors Energy Company Keenesburg Mine Page 10 2010 Kevegetation Monitoring Keport