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COLORADO Division of Reclamation, j&7 Mining and Safety Department of Natural Resources 1313 Sherman Street, Room 215 Denver, CO 80203 April 9, 2018 To: Tabetha Lynch From: Brock Bowles RE: Peabody Sage Creek Mine, C-2009-087 Bond Release No. 4 (SL -4) I have finished my review of the Peabody Sage Creek bond release application no. 4. A summary of each reclamation standard is included below for inclusion into the findings document. Cover Cover data was collected during the 2012 and 2014 growing seasons for the bond release and reference areas. Sample adequacy was achieved for cover in both the bond release and reference areas for 2012 and 2014. The cover reclamation standard uses a weighted average of the two reference areas. The mountain brush area contributes 83% and the sagebrush area contributes 17% to the standard. A complete description of determining revegetation success is detailed in Section 2.05.4 of the permit starting on page 47 and in the SL -4 application. The allowable plant cover in 2012 was 32.4% which exceeded the reclamation standard of 21.7% in a direct comparison test. The allowable plant cover in 2014 was 47.09% which was less than the reclamation standard of 48.1 %. When the reclamation standard is not achieved in a direct comparison test but sample adequacy is achieved, the standard null hypothesis test described in Rule 4.15.11(2)(b) is used to demonstrate revegetation success. The statistical demonstration supported the hypothesis of `no difference' and the revegetation was deemed successful. The cover standard was demonstrated to be successful for both 2012 and 2014. Production Production data was collected during the 2012 and 2014 growing seasons for the bond release and reference areas. Sample adequacy was not achieved in the reclamation areas in 2102 and 2014. Rule 4.15.11(2)(c) is applied when the reclamation standard is achieved but sample adequacy is not met. The production reclamation standard uses a weighted average of the two reference areas. The mountain brush area contributes 83% and the sagebrush area contributes 17% to the standard. The allowable herbaceous production in 2012 was 847.6 lbs/ac which exceeded the reclamation standard of 230.1 lbs/ac. Sample adequacy was not achieved in the reclamation areas in 2012 so fly.. C H 1313 Sherman Street, Room 215, Denver, CO 80203 P 303.866.3567 F 303.832.8106 http://mining.state.co.us I John W. Hickenlooper, Governor I Mike King, Executive Director I Virginia Brannon, Director * r 1876