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2.0 Evaluation of Reclamation Success for Phase III Bond Release • 2.2 POST-MINING LAND USE The post-mining land use for the Irrigated Pasture Reclaimed Area, as stipulated in the permit, is irrigated pasture, and rangeland/wildlife habitat on the Rangeland Reclaimed Areas. Permit No. C-81-013 stipulates that both post-mining land uses have identical reclamation success criteria for vegetative cover and herbaceous production. Species diversity and shrub cover is a success criterion only on the rangeland/wildlife habitat post-mining land-use. The dominant grass species detected on the Irrigated Pasture Reclaimed Area during the 2005 and 2006 sampling events is smooth brome. Western wheatgrass, intermediate wheatgrass, and slender wheatgrass also provide a portion of the cover sampled on the Irrigated Pasture Reclaimed Area. Skeletonleaf bursage and alfalfa are the most abundant perennial forbs sampled on the Irrigated Pasture Reclaimed Area. Annuals, biennials, and species on state or county noxious weed lists are considered less desirable species and some were present in low amounts in the reclaimed areas. In 2005, approximately 12 percent of the relative cover on the Irrigated Pasture Reclaimed Area consisted of less desirable species, primarily yellow sweet clover (biennial forb) and field bindweed. Less than one percent of relative cover was in Canada thistle: Field bindweed and Canada thistle are listed on the Colorado C and B list of noxious weeds, respectively, but are not on the Las Animas County weed list. Thus, these species are not of major concern in the project area and did not need to be removed for comparison to success standards, according to CMDG. Field bindweed was more abundant on the reference area, representing more than 18 percent of the relative cover on the AVF Reference Area compared to only 5% on the Irrigated Pasture Reclaimed Area. In 2006, approximately 14 percent of the relative cover on the Irrigated Pasture Reclaimed Area consisted of less desirable species, primarily field bindweed, compared to more than 29 percent on the AVF Reference Area. Field bindweed represented 9.5 percent and 28.9 percent of the relative cover in the Irrigated Pasture Reclaimed Area and AVF Reference Area, respectively. The dominant grass species sampled on the Rangeland Reclaimed Areas are smooth brome and western wheatgrass. The cool-season grass species diversity requirement is achieved by these two species, and by slender wheatgrass. The requirement to establish two warm-season grasses was satisfied by blue grama and sideoats grama in 2005, and by blue grama and little bluestem in 2006. The species diversity requirement for one perennial forb at greater than 5 percent relative cover is achieved by alfalfa in each year. Overall, nine species of perennial forbs and five shrubs were captured during the sampling events on the Rangeland Reclaimed Areas. On the Rangeland Reclaimed Area in 2005, 25 percent of the relative cover was in less desirable species, primarily yellow sweet clover, compared to 8 percent on the reference area, which was also primarily yellow sweet clover. The excess yellow sweet clover was removed when evaluating if the Rangeland Reclaimed Area met the success standard. In 2006, yellow sweet clover had disappeared with the drier conditions and other less desirable species, including field bindweed, comprised less than 3 percent of the Rangeland Reclaimed Area. A sustainable vegetative community is established on the Irrigated Pasture and Rangeland Reclaimed Areas of the Golden Eagle Mine. The diversity of vegetative species present on the reclaimed areas provides available forage for domestic livestock and wild ungulates. Basin believes the establishment of a vegetative community dominated by predominantly desirable, perennial species, proves that the Reclaimed Areas are capable of sustaining the approved post-mining land uses. • 2215_Go1denEag1e PH3BGND 2006 3-10-08.doc 2-4