2021-12-09_REVISION - C1981010 (7)

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flows (via spoil springs), and surface water infiltration has not been largely impaired. If recharge to the spoils is larger than pre mine conditions,direct surface runoff will be reduced, and an increased amount of groundwater discharge to spoil springs would be expected. Any increased groundwater discharge augments water availability for livestock and wildlife for a greater portion of the year. Protection ofHydrologic Balance Observed hydrologic impacts are consistent with those predicted in the Division's Colorado River Cumulative Hydrologic Impact Assessment. Based on the foregoing observations,the Division finds that the Trapper Mine has minimized disturbance of the hydrologic balance within the bond release block and adjacent areas, and prevented material damage outside the permit area. The Division also finds that the Trapper Mine has not caused hydrologic changes adversely affecting the approved post mining land use in the permit area. Summary and Conclusions Based upon a review of the mine permit, discharge monitoring reports,the applicant's bond release application,the October 2021 bond release inspection and other prior site inspections,the Division finds that Trapper Mining, Inc.has replaced topsoil in accordance with the approved reclamation plan. Trapper Mining,Inc.has established vegetation which supports the approved post-mine land use and meets the approved success standards. As no TDS (Total Dissolved Solids),values for active outfalls and other than a short term,mid-summer 2021 pH excursion,no exceedances of primary effluent limitations have been reported through TMI's monthly and annual water quality reports,the Division finds that the reclaimed area subject to this bond release is not contributing suspended solids to streamflow or runoff outside the permit area in excess of pre-mining levels. The assessment of the probable cumulative impacts of all anticipated coal mining in the general area on the hydrologic balance, as described in Rule 2.05.6(3),has been made by the Division. This assessment, entitled: Yampa River Cumulative Hydrologic Impact Statement,was completed in May 2010. This report is available for inspection at the offices of the Division. In the past,the Division has found that the operations proposed under the Trapper Mine PAP have been designed to prevent material damage to the hydrologic balance outside the permit area [in compliance with Rule 2.07.6(2)(c)]. The Division is in the process of updating the 2010 version of the Yampa River Cumulative Hydrologic Impact Statement. This update will include an analysis of recent data from water quality sampling of the Yampa River and tributaries potentially impacted by the Trapper Coal Mine. See the heading: Evaluation of Hydrologic Impacts above, of this findings document for additional discussion of the hydrologic consequences of mining operations at the Trapper Mine. Permit Number. C1981010 Page 15 of 16