Laserfiche WebLink
Seneca 11 Mine June 2014 <br />SL -6 Phase III Bond Release Request <br />Revegetation Success <br />Vegetation sampling in the Phase III bond release block (referred to as BRB -5 in the revegetation <br />success evaluation report contained in Attachment D and below) and the Seneca II Mine <br />reference areas was conducted in July 2011 and July 2012 by ESCO Associates. The 2011/2012 <br />revegetation success evaluation report for the Seneca II Mine Phase III bond release evaluation is <br />included as Attachment D — Revegetation Success Supporting Documentation. The Phase <br />III bond release block, reference areas and random sample point locations are included on Maps <br />1 - 4 contained in the 2011/2012 revegetation success evaluation report. <br />Successful revegetation for the parameters of cover, herbaceous production, woody plant <br />density (background and concentration areas) and species diversity was demonstrated in <br />both 2011 and 2012 vegetation sampling. The results of those demonstrations are <br />summarized in the following sections. <br />Cover. The Seneca II Mine cover standard and evaluation for success is as follows. The cover <br />success standard is based on a weight averaged value (based on the two primary premine <br />vegetation type contributions to total acreage) for first hit adjusted herbaceous cover derived <br />from sampling in the approved Seneca II Mine sagebrush and mountain brush reference areas. <br />The weighting contribution is mountain brush 83% and sagebrush 17 %. First hit adjusted <br />herbaceous cover is determined from cover sampling in the above two native reference areas <br />with adjustments made for woody plants, noxious weeds and no more than 10% relative cover of <br />annual /biennial weeds. The allowable first hit herbaceous cover standard is determined by weight <br />averaging the values based on the percent contribution of the mountain brush and sagebrush <br />types. This basis value is multiplied by two (2) to arrive at the cover success standard. The Phase III bond <br />release area sample value will be no less than 90% of the cover success standard at 90% statistical confidence. In <br />both the reference area derived standard and the Phase III reclaimed area, the adjusted <br />herbaceous cover is herein referred to as the allowable herbaceous cover. The derivation of the <br />first hit allowable herbaceous cover for the Phase III bond release block and reference areas is <br />included in the discussion and tables in the 2011 and 2012 revegetation success evaluation report <br />included in Attachment D — Revegetation Success Supporting Documentation. <br />5 <br />