2010-02-25_REPORT - C1981028 (6)

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4.4 SPECIES COMPOSITION • The Colorado Division of Reclamation, Mining and Safety considers species composition of the revegetated and reclaimed areas to be an indicator of successful vegetation establishment and a diverse vegetation community. The species composition standard requires that there be at least four perennial species, of which three are warm season grasses and one a cool season grass. No one component of the above four species should comprise greater than 40% relative importance nor less than 3% relative importance. Relative importance will be measured by calculating relative cover of the revegetation species. Vegetation species which may be used in the calculation of species composition may be any plant species not defined as a noxious or prohibited plant species, and may be native or introduced. A comparison of the 2007 species composition data with the revegetation success standard reveals that in the 2002 reclamation areas three warm season grass species and one cool season grass were lacking adequate relative cover to be counted for the species composition criterion. This year, two warm season grasses and one cool season grass species were lacking in sufficient relative cover to satisfy the criterion. The 2006 reclamation area exceeded the number of qualifying cool season grass species (2), but lacked two qualifying warm season grasses. Several warm season grass species were present in the sampling, providing promise for this relatively young, developing area. 4.5 COMPARISON OF VEGETATION COMMUNITY TRENDS • Direct comparison of the 2009 monitoring data for the areas sampled with that of previous years to evaluate long-term trends in vegetation communities cannot be undertaken for the 2002 and 2006 reclamation areas as they have only been monitored from one to three years. The short duration of sampling precludes any significant observations regarding long-term trends at this time. 5.0 SUMMARY Quantitative monitoring of the 2002 and 2006 reclamation areas revealed that the all reclamation areas met the requirements for final revegetation success for total vegetation cover and total herbaceous production. Of the revegetated areas sampled in 2009, neither the 2002 or 2006 reclamation areas met the species composition revegetation success criterion. Table 1 reveals that the total number of species encountered during sampling is significant and diverse in numbers of species, lifeforms, and seasonal variety. The 2002 reclamation areas revealed a significant annual forb component this growing season. While desirable perennial grasses were present in the quantitative cover sampling, their relative cover was below that expected from prior revegetation efforts and adjacent reclamation areas at the Keenesburg Mine. • The 2006 reclamation area has shown significant development of a diverse, effective, permanent vegetation cover, and is expected to continue in their successful development. Coors Energy Company Keenesburg Mine Page 15 2009 Revegetation Monitoring Report