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Quality Control Commission's Basic Standards for Ground Water (Rule 41). <br />Any ground water in alluvial deposits in the bond release area meets the classification of Limited Use <br />and Quality because the alluvial water is of such small volume in these thin, laterally discontinuous <br />deposits that it is not currently used and is unlikely to be used in the future. The Basic Standards for <br />Ground Water have no water quality standazds for the Limited Use and Quality classification. <br />The area disturbed by mining in the bond release area comprises less than I% of the length of the <br />outcrop belt on the north slope of the Williams Fork Mountains where ground water is recharged. <br />This disturbed area is too small to have reduced the regional ground water rechazge below the <br />approximate pre-mining rechazge rate. On a local scale, the disturbed area does not significantly <br />divert ground water flows to surface water flows (via spoil springs), and surface water infiltration has <br />not been impaired; therefore, the approximate pre-mining ground water rechazge rate has been <br />preserved locally. <br />West Buzzard Pond No. 3 has been permitted to remain as a permanent impoundment. West Buzzazd <br />Pond No. 3 and drainage were in good condition at the time of the bond release inspection. Two <br />permanent stock ponds, EPE No. 1 and EPM No. 4, were included in the SL-07 bond release blocks. <br />Many of these stock ponds hold water during the summer months, which supports the post-mining <br />land use by reducing the distance wildlife and livestock have to travel for water. Both stock ponds <br />have been approved to remain as permanent impoundments. The stock ponds and drainages were in <br />good condition. <br />TMI sampled vegetation in the summer of 2004 and the summer of 2005. Rangeland bond release <br />blocks were sampled for vegetative cover, productivity, species diversity, and woody plant density. <br />Cropland bond release blocks were sampled for productivity only as per Rule 4.15.9. TMI uses a <br />reference area for vegetative success comparison for the cropland post-mining land use area only. The <br />cropland reference azea experienced a late frost in 2004. This resulted in the reference area exhibiting a <br />patchy distribution of vegetation with vegetation sampling results exhibiting very high standazd <br />deviation values. Adequacy using the standard adequacy formula was not achieved on the cropland <br />reference area data. Instead, the operator used atwo-sample, one-sided, reverse null calculation to show <br />that an adequate number of production transects had been sampled for both the 2004 and 2005 sample <br />data. The Division agreed with the analyses of the data.. <br />Reclaimed areas with rangeland as the approved post-mining land use were compared to an approved <br />standard. Trapper achieved vegetative success for rangeland cover, productivity, diversity and woody <br />plant density. Cropland productivity on the bond release blocks exceeded productivity on the cropland <br />reference areas as well. Due to non-parametric data distribution of rangeland productivity and woody <br />plant density, TMI demonstrated reclamation success of these two parameters by using the reverse null <br />hypothesis. <br />Trapper Mine, SL-07 Findings ~ May 16, 2006 <br />