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66. It appeazs from Figure 1 of Exhibit 13 that only 2 fills (I and 4) would come close to the <br />• lowermost extent of the surface mine. Map 2.05.4-1, however, show fills being constructed <br />to much higher elevations. Please address this discrepancy in fill construction elevations. <br />Response <br />CTL/Thompson is in the process of revising the stability analysis provided in Exhibit 13. <br />Figure 1 of Exhibit 13 will be revised and submitted with their revision. <br />67. It appeazs from Surface Mine Post-mining Topography Map 2.05.4-1 that the azeas between <br />fills 1 and 4, 4 and 6, 3 and 5, 5 and 8, and 9, 7 and 8 will be affected by mining (as shown <br />by the blue "annual disturbance azea" lines), and then reconstructed to the post-mining <br />topography shown on the map. While Exhibit 13 discusses the geotechnical design criteria <br />for the fills, the only information provided in the application pertaining to the reclamation <br />of the non-fill azeas of the surface mine is found in three sentences on page 2.05-10 (the first <br />of these being "After the contour cut..."), and on page 2.05-40. <br />Section 2.05.3(6) of the Regulations requires the application to explain the removal, handling <br />and storage of all overburden. Section 2.05.4(2)(c) requires the application to contain a plan <br />for backfilling and grading in accordance with 4.14. Section 4.14.2(1)(b) requires backfilling <br />and grading to the most moderate slope possible, not exceeding the angle of repose or such <br />lesser slope as necessary to achieve a factor of safety of 1.3. Certain slopes shown on Map <br />• 2.05.4-1 aze quite steep, and may present stability concerns, as well as reclamation concerns. <br />For example, the azea immediately adjacent to and just west of Fill 5 has a slope angle of 33° <br />(1.Sh:1 v), and a slope length of 200 feet. The azea within the "1999" blue lines that will lie <br />between Fill I and Fi114 has a slope angle of 22° (2.48h:1v), but a slope length of 400 feet <br />and a southeast aspect. <br />The Division recommends the applicant redesign the slopes of the non-fill azeas at the <br />surface mine so that south, southeast, southwest and west-facing reclaimed slopes aze no <br />steeper than 3h:ly, that all other non-fill reclaimed slopes be no steeper than 2.Sh:ly, and <br />that the consttu t oc n (material transportation, segregation, backfilling, compaction) of these <br />slopes will meet the 1.3 factor of safety required by Section 4.14.2(1)(b) of the Regulations. <br />Please provide this information. <br />Response <br />LCC is currently working with its engineering consultants on the geotechnical design of the <br />fill azeas and will submit a response to this comment within the next 30 days. <br />68. [n this same pazagraph, it is stated that "a maximum of 1500 lineaz feet of pit will be open <br />at any one time. A variance is requested for the first cut through the ridge as it will be left <br />open for the second phase of the surface mine...". <br />• <br />19 <br />