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J. J. Dudash -3- December 26, 2006 <br />Section 2.05.3(8). Coal Mine Waste And Non-Coal Processing Waste <br />11. DRMS: Please identify shear strengths and material unit weights used to demonstrate <br />stability of the proposed additions to the approved gob piles [Rule 2.05.3(8)(a)(ii)(D)]. Please <br />reference the sources of information in revised text of revision pages. <br />BRL: Drilling has been performed and a report will be submitted to the Division in February <br />12. DRMS: Please provide a stability analysis [Rule 4.09.1(7)] using the material characteristics <br />requested in item number 9 above in the vicinity of cross section D - D'. The design stability <br />safety factor needs to be 1.5 [Rule 4.10.4(2)]. The configuration should be the proposed cut <br />slopes (original ground) approved by TR-43, and the proposed finished surface of the fill, as <br />illustrated for cross section D - D' on Figure 1 of the application. <br />BRL: Drilling has been performed and a report will be submitted to the Division in February. <br />13. DRMS: Please reconfigure the proposed additional gob piles to leave a space of <br />undisturbed bedrock or soils to accommodate the trace of Ditch D-F 11. This ditch cannot be <br />located on fill materials [Rule 4.09.2(7)]. <br />BRL: There is a separation of the gob piles so ditch F-11 will not be constructed on gob <br />material. See Map 15-3 and Figure 1. <br />14. DRMS: The Division has previously approved terraces at a vertical spacing of 50 feet. <br />However, at slopes of 5 horizontal to 1 vertical, this criteria allows slope distances of 255 feet. <br />This distance may be above the upper limit for sheet flow at slopes this steep. Please consider <br />closer spacing to inhibit rill erosion of the embankment post-mining topography. <br />BRL: The reclamation plan includes extensive roughening and the relative flat (20%) slope <br />offsets the DRMS' concern about the longer slope distance. <br />Section 2.05.4. Reclamation Plan <br />15. BRL: The DRMS' reclamation estimate in the amount of $265,457 is accepted by BRL. <br />2.05.6. Mitigation of the Impacts of Mining Operations <br />16. DRMS: Please revise the Probable Hydrologic Consequences section of the permit <br />application to account for the effect of the increased volume and aerial extent of the proposed <br />gob pile no. 2 on coal leachate and the water quality of the North Fork of the Gunnison River. <br />BRL: See updated permit pages, 2.05-74, 75, 75i, 75ii <br />Section 2.10. Maps and Plans <br />17. DRMS: Please change the disturbed area boundary on Map 03, "Vegetation", Map 04, <br />"Soils", Map 26, "Previously Disturbed Areas" and Map 32, "Topsoil Distribution Plan". <br /> <br />