2012-03-27_GENERAL DOCUMENTS - C1981010

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Revegetation Success Standards Trapper Mining, Inc. sampled vegetation in the summer of 2011 and the summer of 2010. The Operator hired IME consulting firm from Yampa, Colorado to assess the revegetation success. Rangeland bond release blocks were sampled for vegetative cover, productivity, species diversity, and woody plant density. Reclaimed areas with rangeland as the approved post - mining land use were compared to an approved standard. Trapper achieved vegetative success for rangeland cover, productivity, diversity and woody plant density /shrub clump survival. Due to non - parametric data distribution of rangeland productivity and woody plant density, Trapper Mining, Inc. demonstrated reclamation success of these two parameters by using the reverse null hypothesis. Two revegetation monitoring reports were submitted with the SL13 application for areas sampled in 2011 and 2010. These reports outline the methods used to measure vegetative cover, productivity, species diversity, and woody plant density /shrub clump survival. The sampling methods used meet the criteria outlined in Rule 4.15.11 and the permit application. Revegetation monitoring transects were randomly located throughout the bond release block. Each portion of the bond release block had an equal chance of being sampled. Plant cover was measured along twenty 50 meter transects. Ten locations along each transect were sampled using a metal 10 -point frame resulting in 100 data point collected per transect. Plant cover data was used to measure and evaluate species diversity. To measure production, thirty transects were sampled. Three randomly located one quarter meter clip plots were sampled along each transect. The plots were clipped by life forms of perennial grasses and perennial forbs. Annuals, biennials, noxious weeds and shrub production were not clipped. Following clipping, the harvested plant material was oven dried and weighed to determine average production for the bond release block. Modified belt transects were conducted along the same thirty transects used to measure production to determine woody plant density. Also, three shrub clumps were located within the original bond release block; however one clump was removed when parcel F -AB -01 was withdrawn from the release application. Each shrub clump contains 200 shrub pads. Half of each of the shrub pads was counted to quantify that at least 50% of the pads contained 10 living woody plant stems per pad. For range site A, the required herbaceous cover standard is 33% and 19% litter cover for a total 52% effective cover ( "Allowable Cover "). For range site B, the required herbaceous cover standard is 29% and 23% litter cover for a total effective cover of 52 %. For range site C, the required herbaceous cover standard is 23.6% and 20.0% litter cover for a total effective cover of 43.6 %. These standards for each of the range sites are listed on Table 4.4- 1 of the permit. For this release, since the release block consists of all range site types, the revegetation standard for range site A was used to evaluate revegetation success since it has the most conservative standard. According to the revegetation monitoring reports, in 2011, the rangeland reclamation block had a total allowable cover average of 84.4% and a perennial plant cover average of 65.00 %. For the 2011 data, perennial grasses Great Basin Wildrye (Elymus cinereus), Western Wheatgrass (Agropyron smithii), Kentucky Bluegrass (Poa pratensis) and Sheep Fescue (Festuca ovina) dominated the seeded vegetation on the reclaimed site. Alfalfa (Medicago Trapper Mine Phase III Bond Release (SL -13) Page 7 March 27, 2012