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The Division believes it would be appropriate (prior to reclamation of the current refuse area disturbances scheduled for 2009) to give careful consideration to the wisdom of using a seedmix containing numerous aggressive introduced grasses, as well as a diverse assemblage of native species, (particularly as represented by the Large Permanent Sites mix). It may be unrealistic to expect that use of seed mixes containing the introduced grasses will ultimately result in revegetated stands that contain a significant native component, including big sagebrush and associated species. Even the relatively modest standards in the current permit for native species, fortis, and woody plants may not be compatible with use of the aggressive introduced grasses in the current seedmix (including crested, desert, Siberian, and pubescent wheatgrass, smooth brome, Russian wildrye, and sheep fescue). Incompatibility of even relatively minor components of these species with establishment of diverse native communities has been borne out by monitoring results and observations at other mines in northwestern Colorado, and reports from the current technical literature for the western U.S. (see, for example, Monsen, 2005. Restoration Manual for Colorado Sagebrush and Associated Shrubland Communities). Qualitative vegetation survey reports included within recent Deserado Annual Reclamation reports indicate dominance by one or more of these species on permanent reclamation sites seeded in the 1980's at Deserado (with fourwing saltbush and rabbitbrush present in some areas, but no significant establishment or invasion of big sagebrush or associated native fortis). More recently, Refuse Area No. 1 at Deserado was seeded in 1997 with a diverse mix similar to the currently approved Large Sites mix. Reports indicate that portions of the pile not dominated by cheatgrass aze dominated by the introduced grasses, along with one or two native perennial grasses. Seeded fortis are apparently very minimally represented, with shrubs somewhat better represented, but apparently at densities still well below the approved 500 stem per acre standard. The pervasive presence and high density of cheatgrass within sagebrush and greasewood communities in the mine vicinity represents a very significant obstacle to successful establishment and a threat to long term stability of revegetation stands at Deserado. The documented ability of the various introduced grass species to compete with cheatgrass (particularly the species in the crested wheatgrass complex) is the primary reason for their inclusion in the Deserado seedmixes. Various native species that are more compatible with establishment of native sagebrush community components have also been recommended in the literature for their ability to compete with cheatgrass (e.g. bottlebrush squirreltail, Sandberg bluegrass, mutton bluegrass, prairie junegrass, `Anatone' bluebunch wheatgrass, streambank wheatgrass, Pacific aster, blue leaf aster, and rubber rabbitbrush), but performance of the native species in this regazd is not as well documented as the introduced grasses. The introduced sub-shrub forage kochia has been recommended by various authorities as a useful species due to its ability to compete with cheatgrass (among other attributes), and for its apparent compatibility with other species in diverse mixtures. 2