Laserfiche WebLink
• Although the outslope measurements of the waste bank are <br />slightly steeper than the 18.43° slope (3H:1V gradient) as <br />designed by EFMC, the slope angles are significantly gentler <br />than the regulatory maximum of 26.57° for waste bank <br />terraces in accordance with Section 4.10.4(4) of the <br />Colorado regulations. <br />• Refuse material in the waste bank was placed in one-foot <br />lifts, which is thinner than the State regulatory maximum of <br />two feet, as required by Section 4.10.4(3)(a) of the <br />Colorado regulations. <br />• Refuse material in the waste bank has been compacted to <br />95.8$, which is in excess of the State regulatory minimum <br />compaction standard of 90$ as required by Section <br />4.10.4(3)(b) of the Colorado regulations. <br />• The waste bank has attained a static safety factor of <br />2.5, which is 66.7$ greater than the minimum static safety <br />factor of 1.5, as required by Section 4.10.4(2) of the <br />Colorado regulations. <br />• With respect to the south-facing outslope of the waste <br />bank, DMG proposed to deny from EFMC's bond release request <br />one section that measured 20.25° and substantially exceeded <br />the permit requirement. <br />• DMG personnel inspected the thickness of cover material <br />placed over the coal waste and determined the average cover <br />thickness to be 4.72 feet, which exceeds the four-foot <br />permit and regulatory cover thickness requirement. <br />• The area on the north-facing slope of the pad near two <br />catch basins was not considered by the DMG to be part of the <br />approved bond release, is currently being addressed in a <br />permit revision and, as such, is not an issue at this time. <br />Based on the foregoing discussions, I agree that the conditions <br />cited in Part 1 of the TDN, regarding the Starkville Gulch <br />ephemeral stream, did not represent a violation of Section <br />4.05.4(4) of the Colorado regulations. In addition, I agree that <br />the remaining conditions cited in Part 2 of the TDN, regarding <br />the slope angles of the west-facing outslopes of the coal mine <br />waste bank, did not represent a violation of Section 4.14.1(2)(a) <br />of the Colorado regulations. As a result, I find that in <br />accordance with 30 CFR 842.11(b)(1)(ii)(B)(2)-(4), the DMG did <br />take appropriate action and has shown good cause for releasing <br />phase I bond on Raton Creek Mine. <br />4 <br />