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bond release application, SL-07, have been approved for Phase I and II bond release during SL-01, SL- <br />02, SL-03, SL-O5, or SL-06. Final reclamation success was evaluated For vegetation success for <br />vegetative cover, herbaceous productivity, species diversity and woody plant density on lands <br />designated as range sites A and B. On lands designated as range site C, final reclamation success was <br />evaluated for vegetative cover, herbaceous productivity and diversity. Lands with post-mining land use <br />of cropland, herbaceous productivity is the only parameter used to determine final reclamation success. <br />The condition of the permanent impoundments within the SL-07 bond release azea was evaluated at the <br />time of the bond release. The reclaimed landscape was evaluated for evidence of erosional features, <br />TMI does not propose to eliminate the SL-07 bond release azea from the permit boundary area at this <br />time. Evaluation of the post-mining land use was considered during the Division's review as well. <br />Impacts to surface and ground water was analyzed during the Division's review of the SL-07 bond <br />release application. <br />IIL OBSERVATIONS <br />In accordance with Section 3.03.2(2), the Division has evaluated whether pollution of surface or <br />subsurface water is occurring, and the probability of future occurrence of such pollution. The <br />evaluation considered information in the following documents: the Probable Hydrologic <br />Consequences section of the permit application, Annual Hydrology Reports submitted by the <br />operator, the Division's Annual Hydrology Report review memoranda, and documents in the SL-07 <br />bond release application and file. The results of the evaluation are summarized below. <br />The operator has monitored the quality and levels of ground water in wells inside and downgradient <br />from the bond release area. These wells were completed in the HI coal sequence (well GF-4), QR <br />coal sequence (wells GD-2 and GF-6), the overlying 2nd and 3`d White Sandstones (wells GB-2 and <br />GF-5), and spoil/ash backfill (wells GD-3 and GF-7). Historical data from the backfill wells indicate <br />leachate forms in the spoil/ash backfill. This leachate is high in dissolved solids (TDS), mainly <br />sulfate, and is alkaline. TDS concentrations appear to peak around 4,000 mg/I. This concentration <br />may continue for several hundred years, as predicted for the Seneca II Mine in Routt County, <br />Colorado (USGS Water-Resources Investigations Report 92-4187). The alkalinity (pH near 7) <br />appears to have prevented significant mobilization of metals in the spoil/ash backfill. The elevations <br />of water levels in the bedrock wells aze higher than the highest elevations to which leachate levels can <br />be expected to rise in spoil/ash backfill; therefore, significant invasion of the bedrock units by <br />leachate is unlikely. Spoil/ash leachate has not been detected in the downgradient bedrock monitoring <br />wells, although ground water flow velocities in the bedrock units may be too slow for leachate to <br />have reached the farthest downgradient wells. <br />The absence of leachate plume development in the bedrock units indicates that for bedrock units in <br />and adjacent to the bond release area, the mine operator is in compliance with the Colorado Water <br />Trapper Mine, SL-07 Findings 6 May 16, 2006 <br />