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II. CRITERIA AND SCHEDULE FOR BOND RELEASE <br />PHASE III <br />Rule 3.03.1(2)(c) states that the final portion of performance bond, "shall be released when the <br />permittee has successfully completed all surface coal mining reclamation operations in <br />accordance with the approved reclamation plan, and the fmal inspection procedures of 3.03.2 <br />have been satisfied. This shall not be before the expiration of the period specified for <br />revegetation responsibility in 3.02.3." Rule 3.03.1(4) states, " No bond shall be fully released <br />until all reclamation requirements of these Rules and the Act are fully met...". The same rule <br />goes on to state, " No acreage shall be released from the permit area until all surface coal mining <br />and reclamation operations on that acreage have been completed in accordance with the <br />approved reclamation plan." <br />The portion of land requested for release includes the truck turn azound azea, the shop and <br />facilities azea (buildings were left at the landowners request), and the Alluvial Valley Floor <br />(AVF). The post mining land use of the alluvial valley floor is irrigated pasture. The buildings <br />and facilities remaining include two shop buildings, two trailer houses, and a well that has been <br />transferred to the landowner. <br />Greystone collected vegetation data on the irrigated pasture in July 2001 and June 2002. <br />Sample design entailed random distribution of transect locations for cover. Three production <br />quadrats were laid out at regulaz intervals along the cover transects. The data from the three <br />production plots were designed to be averaged for each transect. Sample adequacy for <br />production was achieved on the data collected in 2001. Colorado experienced a serious drought <br />during the spring and summer of 2002. The low water level in Stollsteimer Creek precluded <br />irrigation of the reference and reclaimed pastures in 2002. 2002 production data reflect drought <br />and dryland conditions. As a result, herbaceous production data exhibited an extreme degree of <br />variability. Data ranged from a low of O.lg/O.SMZ to a high of 70.4 g/O.SMZ on the reclaimed <br />pasture. This high degree ofvaziability necessitated a high number of samples to be collected to <br />achieve sample adequacy. Greystone presented the 2002 production data as I50 individual <br />quadrats, instead of 50 composited samples. When the 2002 Reclaimed pasture data is analyzed <br />as called for in the design plan, sample adequacy is not met. The Snedecor-Cochran sample <br />adequacy formula recommended by DMG in the Guideline Regazding Selected Coal Mine Bond <br />Release Issues, dated April 18, 1995, on page 21, was used to calculate sample adequacy. <br />Greystone collected 50 random transects with 3 regulazly distributed quadrats along each <br />transect. Analyses with the sample adequacy formula calculates a minimum of 91 sample <br />points to achieve sample adequacy of the population. Greystone's analyses of this data as 150 <br />independent points indicates that sample adequacy has been achieved with 150 samples. <br />However, the basic assumption that the 150 points aze independent is slightly flawed. Every <br />three production quadrats are dependent upon a randomly located cover transect. Greystone <br />analyzed the 2002 pasture reference azea in the same manoz; determining that 60 quadrats did <br />not achieve sample adequacy. The Division composited the quadrat data to correspond to the 20 <br />5 <br />