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Revegetation Criteria <br />The Bowie No.l Mine permit has two different technical cover standards for the East and West <br />Mine areas. The cover standard and results for each area affected in this bond release are <br />described below. <br />The East Mine area is also known as the original Orchard Valley Mine which includes the Run <br />of Mine (Timber Storage Area) bond release area. The vegetation for the East Mine area is <br />considered to be successful if the total ground cover exceeds 40% (Volume 9A, Vegetation -Part <br />2, page 6). The approved permit states that the ground cover is required to `exceed 40%'; as <br />such, the statistical 90% of standard that typically applies to the success standard (Rule <br />4.15.11(2)(a)) is not applicable in this case. BRL reported in the December 2013 Revegetation <br />Evaluation Report that the overall vegetation cover was 54.4%, of which perennial species <br />contributed 9 1. 1 % relative cover and annuals/biennials contributed 8.8% relative cover <br />(annuals/biennials are not allowed to exceed 10% relative cover). Noxious weeds contributed <br />0.1 % overall cover, but do not count toward vegetation success. The resulting vegetation cover <br />that qualifies for bond release is 54.3% (minus noxious weeds), which exceeds the required 40% <br />success standard. The East Mine area associated with this SL -05 Phase 11 bond release was <br />sampled to statistical adequacy. <br />The vegetation cover standard for the West Mine is considered to be successful if the total <br />ground cover exceeds 60% (Vol. 1- 2.05 Operation and Reclamation Plans Part 2, page 75). As <br />outlined in Rule 4.15.11(2)(a), 90% of the cover standard is considered a success, which results <br />in a 54% success standard. BRL reported that the overall vegetation cover was 62.5%, of which, <br />perennial species contributed 53.93% average cover and 86.3% relative cover and <br />annuals/biennials contributed average cover of 6.9% and 11.1% relative cover (annuals/biennials <br />not allowed to exceed 10% relative cover). Noxious weeds contributed 1.7% overall cover and <br />2.7% relative cover, but do not count toward vegetation success. The resulting vegetation cover <br />that qualifies for bond release is 60.02% (53.93% plus 6.09%), which exceeds the required 54% <br />success standard. The West Mine area associated with this SL -05 Phase II bond release was <br />sampled to statistical adequacy. <br />Suspended Solids Demonstration <br />BRL's bond release application utilizes a vegetation evaluation performed during June 2013 and <br />subsequent soil loss comparison submitted as part of Technical Revision No. 58 as justification <br />to remove and reclaim the Run of Mine Pond and West Mine No. 1 and West Mine No. 2 Ponds. <br />The soil loss comparison information compares pre- and post -mining sediment yields by <br />calculating the expected sediment yields for both conditions. BRL utilized the Universal Soil <br />Loss Equation (USLE) calculation method which calculates the expected average annual soil loss <br />per acre of land. <br />In the USLE comparison, only the "LS" and "C" factors are varied between the pre -mining and <br />the post -mining calculations; all other variables are constant for pre- and post -mining. The <br />baseline calculation uses baseline vegetation cover values obtained from the Vegetation <br />