2012-12-06_REVISION - C1981008 (4)

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Response: No noxious weeds were encountered during the sampling of the vegetation relative to this bond release application as defined in NH2 Mine Permit. Therefore, none of the cover or production values have any contribution from these plants An aggressive noxious weed control program is practiced at the NH2 Mine. 3. Continued: The revegetation section of the release application should include a description of the sampling methods used, success standard comparisons, and statistical procedures (including sample adequacy calculations and statistical tests). Summarized transect data (total vegetation cover and absolute cover by species, rock, soil, or litter, for each transect) and woody plant density data should be included in additional to data summary tables. The revegetation will be considered successful if the criteria of Rule 4.15.8, and the standards set forth in the approved permit, have been achieved. For success comparison and statistical evaluation purposes, the cover and production contribution of any noxious weed species or "excess" annuals and biennials should be discounted (i.e. subtracted from each sample observation) prior to success comparison for cover and production. Response: A through discussion of the sampling methods used in all of the vegetation sampling efforts are found in the attached reports. The revegetation success standards as contained in the Permit have been cited previously. The sample adequacy calculations are found in the reports or for the revisions made to the BIO -Logic data, are found in the accompanying text. Data for total plant cover, absolute and relative cover along with mean values for litter, rock and bare ground are presented in the modified tables. No listed noxious weeds were encountered in the sampling efforts on either the Irrigated Pasture reclaimed or reference areas. Since no "excess "annuals and biennials were observed, cover of these species did not need to be subtracted for purposes of success comparisons. Statistical Tests. The IME reports from 2010, 2011 and 2012 all contain the specific statistical tests as required by Rule 4.15.11, therefore, reference to the appropriate text sections of these reports is made in the following summary. The BIO -Logic reports for their 2008 monitoring efforts contains no statistical mean comparisons, while their report for 2009 contains these calculations. Since some of their data had to be modified to reflect the current definitions of "noxious weeds" as found in the NH2 Mine Permit and standardize their usage of plant life forms, their data have been subjected to the accepted statistical testing requirements where necessary. In the following summary, a year by year, tract by tract statistical analysis is presented which specifically addresses the revegetation success criteria requirements found in Rule 4.15.11. In the following narrative, and in the previous production tables, IME did not apply the "soil correction factor" to all of the production data tables, obtained from the various reclaimed tracts evaluated in this bond release effort. However, these values are calculated in the statistical calculations of the mean production values in the following narrative. Since the mixture of species planted on the Irrigated Pasture reclaimed tracts is SL -14 03DEC12.wpd 50