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Colowyo SL4 2 October 29, 2010 <br />Mountain Shrub reference 63% =live vegetative cover (Ivc) <br />Sagebrush reference 57.85% Ivc. <br />Acreage weighted results Reference areas=60.68% Ivc. <br />2008 SL4 phase II bond release block=71.48% Ivc. <br />Noxious species were minor component accounting for 5.79% relative cover. The only noxious species identified in the <br />2008 sampling event was Cheatgrass (Bromus tectorum). Annuals and biennials were minimal too, accounting for 8.46% <br />relative cover. Even with removal of the Cheatgrass component to the 2008 cover value, the 2008 cover measured on <br />the bond release block was acceptable and the bond release block cover still met the cover standard. The 2008 <br />reference areas exhibited a high concentration of Cheatgrass as well; 9.84% relative cover in the mountain shrub <br />reference area, and 38.12% in the sagebrush reference area. <br />The Division's Guideline for the Management of Noxious Weeds on Coal Mine Permit Areas (dated 1990) suggests <br />that relative cover of more that 3% attributable to one noxious species or a combination of noxious weed species may <br />indicate a problem. The data from 2006 measured Cheatgrass concentration as 21.42% relative cover and 2007 showed <br />a marked decrease with Cheatgrass exhibiting 5.24% relative cover. The 2008 data measured Cheatgrass concentrations <br />in the reference area well in excess of that measured on the reclaimed area, the Division does not consider the 2008 <br />Cheatgrass concentration on the bond release block as problematic. <br />Results: 2008 Bond Release Block cover > 2008 Acreage weighted reference area cover <br />Annual grass species measured in the reference areas was unusually high in 2008, accounting for 24% relative cover. <br />Annual species were less in the phase II bond release block, with only 11.8% relative cover. Even correcting for the <br />higher concentration of annuals in 2008, the bond release block was considered successful for vegetation establishment. <br />Diversity: Eleven species exhibited greater than 3% relative cover, but less than 50% relative cover. Eight species were <br />perennial grasses, and two were perennial forbs. None of these species were considered noxious or toxic. The diversity <br />standard for this bond release block (parcels reclaimed prior to 2008) require at least two cool season grasses with <br />between 3% and 50% relative cover, and all forbs combined with between 1% and 50% relative cover. Although <br />diversity is not a requirement of phase II bond release, the Division evaluates this parameter to determine if the <br />reclaimed areas is progressing towards final success criteria. The SL4 Phase II Bond Release Block achieved the required <br />diversity standard with the 2008 vegetation sampling. <br />2009 results: <br />2. Adequacy concern-comparison with Exhibit 2 Phase II bond release map and 2009 vegetation report map 1) <br />page 3 of Cedar Creek report, shows transect 37 falling to the east of parcel WP004. Cedar Creek Associates <br />(CCA) included WP001 in their sampling list. The parcel that transect 37 was located in does not appear to be <br />included in Colowyo's requested area for Phase II bond release. This parcel should either be included in the <br />bond release request or the data from this parcel removed from the 2009 vegetation data. Even with transect <br />37 data removed from the data set, the 2009 data shows cover was successful compared to the weighted mean <br />of the two reference areas.