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DETERMINATION OF SAMPLE ADEQUACY <br />Sample adequacy for the data collected was evaluated based on total allowable live foliar herbaceous <br />cover using the following expression: <br />mmn = 1 — S 2 <br />(dx )2 <br />Where: <br />ti = minimum sample size <br />s = Sample variance (n -1 degrees of freedom) <br />d = Precision (0.10 for cover and production) <br />= 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 DEVELOPMENT OF REFERENCE AREA — BASED PERFORMANCE STANDARDS <br />Corrections for Noxious Weeds and Excess Annuals <br />Upon the formal comparison of cover and production data from reclaimed areas to applicable <br />performance standards, observed total all -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, all -hit herbaceous cover data from reference area sampling is used as per SCC <br />Mine permit provisions. <br />Upward Adjustment of the Mountain Brush Cover Standard <br />Sample adequacy for total vegetation cover was achieved for the reference areas and BRB -1. For total <br />allowable herbaceous cover, adequacy based on all -hit values was achieved for BRB -1, the Aspen <br />5 <br />