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revegetation monitoring data, the Division found the woody plant density to be 1,433.4 stems <br />per acre in 2011 and 1,411.8 stems per acre in 2010 without the transects located in parcel F- <br />AB -01. The shrub clumps and woody plant densities were considered successful for the bond <br />release block. <br />Based on the data presented in the two reports prepared by IME, the revegetation at the <br />Trapper Mine is deemed successful. The reports correlate with what was observed by the <br />Division during the on -site bond release inspection conducted August 31, 2011. Based upon <br />the Phase III Bond Release Application and the field inspection, the Division finds that the <br />Phase III vegetation requirements for Trapper Mine meet the revegetation success criteria <br />approved in the permit. <br />Post Mining Land Use <br />TMI's objective is to restore the affected areas to the land uses prior to mining as indicated in <br />section 4.2 of the permit. There are three significant land uses within the permit boundary; <br />farming, grazing of domestic livestock and use by wildlife. The bond release block does not <br />contain farmland and thus will be used as rangeland for livestock and wildlife. The <br />reclaimed lands have vegetative cover composed of a variety of grasses, forbs, and woody <br />shrubs as described in the above sections. The species, seasonality and forage characteristics <br />of the reclaimed vegetation are suitable for the approved post - mining land uses. The <br />Division has observed livestock grazing and substantial wildlife use of previously reclaimed <br />areas. TMI reports on page 6 of the SL -13 application that mule deer numbers have <br />remained stable since mining began in the mid 1970's. They also indicated elk numbers have <br />increased by an order of magnitude and pronghorn have begun to use the area. Although <br />noxious weeds were found at the site, they contribute a small percentage of the relative cover <br />of the bond release block (2.13% in 2011 and 5.54% in 2010). The revegetation success <br />standards were based on what would be necessary for the land to properly function to <br />accommodate the post mine land uses. Based on the achievement of these requirements, the <br />Division finds that the revegetation on the Trapper Mine reclaimed areas is capable of <br />supporting post - mining land use. <br />Evaluation of Hydrologic Impacts Required by Section 3.03.2(2) <br />Rule 3.03.2(2) requires the Division to evaluate hydrologic impacts prior to releasing <br />reclamation liability. This evaluation must consider whether pollution of surface or <br />subsurface water is occurring and the probability of future occurrence of such pollution. The <br />Division's evaluation is summarized below. <br />Ground Water Impacts <br />TMI has monitored the quality and levels of ground water in mine backfill aquifers using <br />wells GD -3, GF -5, GF -7 and GF -11. These four wells were all included within the SL -4 <br />Phase III bond release area. However, because they are used as ash monitoring wells they <br />are still sampled and are representative of backfilled aquifer conditions occurring in <br />Trapper Mine <br />Phase III Bond Release (SL -13) <br />Page 10 March 27, 2012 <br />