2011-05-05_PERMIT FILE - C1981041

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Backciround According to permit documents, success criteria and standards that were initially established for this mine were as follows: • 90% of the ground cover of the approved reference area. • 90% of the production of the approved reference area. • Woody plant density of 800 live shrubs per acre. • One perennial cool- season grass species with >3% relative cover • Total perennial warm - season grass species >_ 3% relative cover. • Total perennial forb species >_ 3% relative cover. • No reclaimed area shall have a single species that represents > 40% relative cover. At the request of Snowcap, Cedar Creek evaluated the species diversity success standard during 2001. Per Cedar Creek's recommendations from that evaluation, given consultations with the Colorado Division of Minerals and Geology (CDMG), new species diversity success standards were eventually adopted. They currently are as follows: • Total perennial cool- season grass species relative cover >_0.5 %. • Total perennial warm - season grass species relative cover >_2.0 %. • Total perennial forb and suffrutescent (sub- shrub) species relative cover _ >0.5 %. • No reclaimed area shall have a single species that represents greater than 70% relative cover, with the exception of annual grasses. The annual grass component shall not exceed 70% relative cover unless the annual grass component in the corresponding reference area also exceeds 70 %. In such instances, the relative cover of the annual grass component of the reclaimed area shall not exceed the relative cover of the annual grass component in the reference area by more than 5 %. Rationale and justification for technical revision of vegetation success criteria / standards Cover With regard to the success criterion for vegetation cover, the permit does not specify if the comparison for success should be total vegetation cover (all vegetation lifeforms) or only perennial cover. For projects in higher elevation and precipitation zones in Colorado, total vegetation cover can readily be used as a standard because both the revegetation and undisturbed comparison areas are dominated by perennial species and annual cover is usually low (<10% of the vegetative composition). However, projects in lower elevation, drier precipitation zones in Colorado are more subject to invasion and dominance by annual grasses and forbs (both in reclamation and surrounding native areas). For example, the undisturbed areas surrounding the reclaimed units at the Snowcap Mine (including reference areas) exhibited annual vegetation that contributed 70% to 85% of the total vegetation cover in 2010. Given this circumstance, the best variable to judge "sustainability" of desirable vegetation in the foreseeable future is perennial cover. Therefore, Snowcap requests a technical revision of the cover standard to read "90% of the perennial vegetation cover of the approved reference area " TR -60 A14 -11 -2 (New 01/11)