2009-10-13_REVISION - C1982056 (2)

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Response: The 20 million cubic yards of waste material is in addition to the existing 3 million yards, for a total of 23 million yards. 16. Rule 2.05.4(2)(d) requires a reclamation plan that includes a description of the operator's plan for removal, storage and redistribution of topsoil, subsoil and other materials to meet the requirements of Rule 4.06. Although TCC commits to replacement of salvaged topsoil, the text leaves the thickness of topsoil required for replacement ill-defined. The text directs the reader to the Reclamation Cost Estimate, or Map 29, or vaguely states that topsoil will be replaced. The Division recognizes that revised page 2.05-97.5 states that a total of 4.0 feet of cover and topsoil will be replaced over the graded waste material, but the division requests that the topsoil replacement thickness be clearly stated in the text and not referred to in an exhibit. Response: The average soil material thickness to be replaced on regraded portions of the proposed CRDA expansion is 1.5 feet. 17. Please provide language in the permit which confirms that the inspection and testing program recommended in the NWCC Geotech report will, in fact, be utilized during construction of the expanded CRDA, and that all pertinent requirements of Sections 4.10.2 and 4.09.1(11) will be met. Response: The text has been revised to include a commitment to complete the Inspection and Testing program, as recommended in the NWCC Geotech report, during construction of the CRDA expansion, as well as a statement on compliance with applicable provisions of the referenced regulatory requirements. 18. It is the Division's determination that the CRDA underdrain proposed by this revision accomplishes the intent of Rule 4.10.3(5). The presence of the underdrain, as designed, will ensure that the applicable safety factor of 1.5 will continue to be achieved; will serve to increase the stability of the fill by preventing any significant build-up of hydrostatic pressure within the pile; and will protect the surface and groundwater in accordance with the requirements of the Rules Contour lines (existing), as shown on the Phase 1 Grading Plan (Sheet No. C-102), reveal the presence of a topographic flow path beginning approximately 500 feet ESE from the coal stockpile tube and running perhaps 800 feet SSE to intercept the Phase I Underdrain. No underdrain has been proposed to occupy this flow path. Please incorporate an additional underdrain at this location, or provide sufficient justification which explains why such underdrain should not be required. Response: When viewed at a larger scale, or on the ground, the referenced contours reflect the alignment of the existing Coal Refuse Haulroad, used to transport refuse to the existing Refuse Pile. As construction of the CRDA expansion proceeds, refuse fills will encroach on and eliminate this portion of the existing road, effectively blending with the existing terrain. Because no natural drainage currently exists in this location, construction of a finger drain is not warranted. It should be noted, however, that a small topographic basin will be formed by the CRDA Expansion and the adjacent roads, where flows from the west (RDA-1 and RDA-3), and from the core drain will intersect, prior to discharge to Pond D through the existing culverts under the road. 19. The CRDA design proposed has been shown to be stable (with a Factor of Safety>1.5) with respect to any large, circular failure. However, the data provided by NWCC indicate that shallow failures on the face of the fill slope may be somewhat more likely to occur (although not with dire