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Herbaceous Production. Herbaceous production will be determined by harvesting <br />current growing season above ground herbaceous vegetative biomass from randomly <br />located quadrats. Quadrats will be located in conjunction with cover transects. Quadrat <br />size will be determined based on predominant vegetation characteristics, and will be <br />consistent with requirements of the Colorado Division of Minerals and Geology. At this <br />time, previous experience suggests that 0.25-0.50 m2 quadrats will adequately represent <br />the vegetation present in the reclaimed areas. Harvested material may be separated by <br />life form (perennial grasses, annual grasses, perennial forbs, and annual £orbs) and dried <br />to a consistent weight in accordance with accepted scientific practice. For bond release <br />sampling, sufficient numbers of samples will be collected to reach sample adequacy. <br />Woody Plant density. Since there is no revegetation success standard for woody plant <br />density at the Keenesburg Mine, no woody plant density sampling is proposed. <br />Species composition. Species composition data will be derived from relative vegetation <br />cover data. All species sampled during cover sampling will have relative cover data <br />tabulated for comparison to the species composition standard. <br />Sample adeauacv. For bond release purposes, a minimum of fifteen cover transects <br />and/or fifteen production quadrats will be sampled in any reclaimed area parcel. For <br />vegetation monitoring purposes, the minimum number of samples in reclaimed areas may <br />be less, with the agreement of the CDMG. <br />Sample adequacy calculations will be made for both vegetative cover and herbaceous <br />production sampling in any reclaimed area. The following formula will be used for these <br />calculations: <br />ninin = <br />(t)2 (s)2 <br />(d Xbw)2 <br />where: nmin = minimum sample size <br />n = number of samples <br />t = the Student's t distribution value at the 901/o confidence level <br />for n-1 degrees of freedom <br />s = sample standard deviation (s)2= sample variance <br />d = percent acceptable deviation from the mean (10%) <br />Xbar = sample mean <br />Sample adequacy will be calculated for vegetation cover and herbaceous production <br />sampling. Parameters will be tested at the 90% confidence level. Confidence levels <br />achieved for each parameter will be calculated and reported. <br />iiG�- <br />