Laserfiche WebLink
NOTES ON THE COMPARISON OF DATA TO APPLICABLE REFERENCE AREA STANDARDS <br />• Upon the formal comparison of cover data from reclaimed areas to applicable performance <br />standards, observed total first-hit herbaceous cover percentage must be adjusted for excessive <br />contribution by annual / biennial species (CDMG 1995, Guidelines Regarding Selected Coal Mine <br />Bond Release Issues, 1 (IV)A(4)). Herbaceous cover values used in such comparisons also must <br />exclude values for species present on the Routt County Prohibited or Restricted Noxious list or <br />that are listed as noxious by the State of Colorado (Colorado Dept. of Agriculture, Division of <br />Plant Industry, Title 35, Article 5.5, 101-119, Lists A and B of Rules as replaced 2003). <br />For purposes of assessment of reclamation adequacy at the Seneca IIW Mine, all-hit herbaceous <br />cover data from reference area sampling used as per Seneca IIW Mine permit provisions. <br />It is also to be noted that the data from the five reference areas are weighted in accordance with <br />the original relative abundance of the types in the pre-mining landscape. It was necessary to <br />sample each to adequacy (see below) but in the process of weighting, a reliable estimate of <br />variance is lost. Thus the reference area standard is thereafter in the process treated as a <br />technical standard (i.e. without confidence limits) and one-sample t-testing is used. <br />HYPOTHESIS TESTING APPROACHES <br />• Percent absolute (foliar) first hit herbaceous vegetation cover of the Phase II Bond Release Area <br />>_ 90% of the weighted absolute foliar all- hit herbaceous vegetation cover from the reference <br />areas (weighted based on the following extents of types in the pre-mining area to be disturbed as <br />shown in the table below). <br />I Vegetation Type % of Pre-mine <br />Sagebrush/Snowberry 31.3 <br />Mountain Brush 34.5 <br />Aspen Woodland 11.0 <br />Steep Mountain Brush 12.8 <br />Alkali Sage./West. Whtgrs. 10.4 <br />Vegetation Type % of Pre-mine <br />These reference areas were sampled to adequacy to establish the standards for comparison <br />against reclaimed area values. If after 15 cover samples have been completed in Phase II Bond <br />Release Area, sample adequacy had been achieved and the reclamation area mean total <br />• allowable herbaceous foliar cover were above 90% of the reference area-derived standard, an <br />affirmative indication of reclamation cover success was to be asserted. <br />5