2008-07-02_PERMIT FILE - C1996083 (3)

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Until such time as standards for the variables of cover and production can be developed under Colorado's regulations, Bowie will continue to utilize "a weighted average comparison method of determining success for the areas seeded with the upland seed mix". Such weighting will be based on pre-disturbance acreages of the Juniper Woodland and Mountain Shrub communities as applied to reference area variables collected for bond release. However, as indicated on Table E5-1 and discussed on several occasions earlier in this document, the Juniper Woodland and Mountain Shrub reference areas exhibit certain complications. These complications are as follows. First, the Mountain Shrub reference area is located high in the permit area and on an east-facing slope. As a result it receives significantly more precipitation and is therefore, exemplary of mesic Mountain Shrub as opposed to xeric Mountain Shrub more typical of disturbance areas. Mesic Mountain Shrub exhibits substantially greater ground cover and production than does the more xeric Mountain Shrub. Cedar Creek first noted this discrepancy during the sampling effort in 2003 for the previous new Gob pile permit revision. Second, the current Juniper Woodland reference area will be lost to the new Gob pile facility. The new Juniper Woodland reference area has been located in the only reasonably-sized remaining stand of Juniper Woodland left within Bowie controlled lands. However, contrary to the old reference area, this new location is on a steep southeast-facing slope that presents more xeric conditions (see Map ES-1). As such, ground cover and production are notably reduced in comparison to the old Juniper Woodland reference area that, similar to the baseline area, is on a flat to gently sloping bench. As a result, statistical testing between potential disturbance areas and reference areas (including a comparison between the old and new Juniper Woodland reference areas) results in several validation failures as indicated on Table E5-1. In fact, of all the comparisons, the only one that passes is between the new reference area and the Juniper Woodland baseline area for production. Therefore, anon-standard technique for documenting successful revegetation using these reference areas must be utilized. In this regard, it is Cedar Creek's recommendation that for revegetation performance criteria for the variables of ground cover and production, each reference area (new Juniper Woodland and old Mountain Shrub) will still be used in an acreage-weighted manner for testing purposes. However, "baseline-adjusted" ground cover and herbaceous vegetation production variables shall be utilized for comparison. Once the future ground cover and herbaceous production has been determined with a statistically adequate sample (where necessary), the "adjusted" reference area mean for each variable will be determined by multiplying each future reference area mean value by the ratio of the pre-mining baseline versus reference area (measured in 2006) as follows: • cC~~n~ ~~~~ Ass®cn~~s, INC. 19 Exhibit 5 -Vegetation Resources