2003-12-22_GENERAL DOCUMENTS - C1982057

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The cover standardjor mine area reclamation and south exension area reclamation will be based on adjusted weighted average reference area herbaceous cover. The reference area herbaceous cover value will be doubled to set the success standard For all mine area vegetation this adjustment is deemed appropriate, because unadjusted reference area herbaceous cover in [he mine area vegetation types would be insu~cten[ to control erosion; whereas use ofto[al cover would result in a standard unlikely to be achieved for decades, given the dense canopy associated with late successional shrub communities in the mine area. In contrast, the sro~cer success standad section on pages 39a through 40b of Tab 22 of the permit application seems to indicate that there are two different approaches to evaluation of revegetation cover success for the mine area; one approach applicable to the original portion of the II-W permit area, and a different approach for the South Extension portion of the permit area. The natTative is somewhat confusing, and clarification is necessary. The narrative on page 39a begins For all reclaimed //-W areas, successful revegetation for the parameter of cover will be evaluated as follows. The narrative then describes the procedure as described in the Findings of Compliance, with the "doubled weighted reference area herbaceous cover". The narrative does not specify whether the cover value is based on "1" hit" or "all hit" cover. Historically, "I~` hit" cover has been recommended, but this should be clarified if the approach is to be used. A distinctly different approach to evaluation of cover success is described for the II-W South Extension Area, beginning with the first narrative paragraph on page 40, and continuing through the next to last paragraph of page 40a. Under this approach, the extent of herbaceous cover is assessed based on use of "all hit" weighted reference area cover data. The total weighted herbaceous cover value obtained using this approach is not doubled. However, the weighted "all hit" herbaceous cover from the reference areas would be adjusted by a ratio derived from the "weighted average of total hits per sample for a given set of reference area data" compared to "the average total hits per sample for the reclaimed area being tested". It is not clear to us from the narrative description exactly how this ratio is calculated or why it would be an appropriate method to "adjust for the differing shvcture of reclaimed and reference communities". Clarification of the narrative and inclusion of example data to demonstrate the approach and to support the assertions would be helpful and is requested. We note that an approach similar to that described was presented in the 2002 revegetation monitoring report, but the ratio employed th that presentation was "relative first hit cover of herbaceous species divided by relative all-hit cover of herbaceous species", for each reference area and the reclaimed parcel evaluated. This ratio is not consistent with the ratio described m the permit text. The approach in the annual report lowers the mean cover value by a relatively large amount in woody communities where the layered structure results in relative "first-hit" herbaceous cover that is appreciably lower than relative "all-hit" herbaceous cover. The effect is most pronounced in aspen and mountain shmb, with less of an effect in sagebrush/snowberry, still less in alkali sagebmsh/westem whea[gmss, and no effect th the reclamation stand evaluated, where relative herbaceous cover was 100% for both "1"hit" and "all-hit". Further confusion regarding method of cover success evaluation is caused by narrative in the last paragraph of page 40a, continuing on page 40b. This paragraph includes narrative justification for doubling of the "weighted herbaceous cover value". This parngraph would appear to be out of place, since apparently the "doubling" adjustment is meant to be applied only to the original permit area standard, as described on page 39a. To summarize, the entire discussion of cover success evaluation beginning on page 39a and concluding on page 406 is muddled and confusing. There apparently are two different approaches, but the narrative 18