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Assessment of Reclamation Adequacy <br />GENERAL <br />Formal (statistical) hypothesis testing (see below) was undertaken for the Phase III Bond Release Block <br />(post -law, Permanent program lands). <br />DETERMINATION OF SAMPLE ADEQUACY <br />Sample adequacy for the data collected was evaluated based on total first -hit vegetative cover using the <br />following expression: <br />t 2 S 2 <br />n,,, = rdxl2 lJ <br />where``: <br />nR, = minimum sample size <br />s2 = Sample variance (n -1 degrees of freedom) <br />d = Precision (0.10 for cover and production) <br />x = Sample arithmetic mean <br />t = The (a =.10) t -table value for a 1 tail t -test, n -1 degrees of freedom (infinite <br />degrees of freedom may be used if n >30) <br />n =Sample size <br />All such calculations were based on data from a minimum of fifteen samples. <br />NOTES ON THE COMPARISON OF DATA TO APPLICABLE REFERENCE AREA STANDARDS <br />Upon the formal comparison of cover and production data from reclaimed areas to applicable <br />performance standards, observed total first -hit herbaceous cover percentage and collected production, <br />must be adjusted for excessive contribution by annual / biennial species (i.e. no more than 10 percent <br />relative cover or production, CDMG 1995, Guidelines Regarding Selected Coal Mine Bond Release <br />Issues, 1(IV) A(4)). Herbaceous cover and production values used in such comparisons also must <br />exclude values for species present on the Routt County Prohibited or Restricted Noxious list or that are <br />listed as noxious by the State of Colorado (Colorado Dept. of Agriculture, Division of Plant Industry, Title <br />35, Article 5.5, 101 -119, Lists A and B of Rules as replaced 2003). For purposes of assessment of <br />reclamation adequacy, first -hit herbaceous cover data from reference area sampling is used as per <br />Seneca II Mine permit provisions. <br />5 <br />