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Tom Bird, GCC Energy <br />C -1981 -0351 TR -20 PAR <br />29- Nov -2013 <br />Page 9 of 12 <br />drains and ditches, but it is not clear that the proposed configuration of the West <br />Waste Bank has considered the final reclamation of the site, wherein the stream <br />channel will be reestablished from south to north. Please address the relation of the <br />proposed West Waste Bank to the post- mining topography and surface drainage for <br />the King I site. (This issue would be appropriate to address in the permit, not <br />necessarily in the Trautner Report.) <br />4. 6.0 Reconstruction of Bench and Highwall Mine Waste Bank <br />In general, the outline proposed for construction of the West Waste Bank is in conformance <br />with the Rules and permit. We do, however, have a few comments on this section: <br />a) In 6.2, Trautner recommended that they should be present during the earthmoving <br />phase to evaluate the uniformity and general consistency of the material as it is moved. <br />Was a representative of Trautner present during any part of the earthmoving process? <br />b) In 6.3, Trautner recommends compacting the material to 95% of the maximum dry <br />density (standard Proctor). This exceeds the minimum of 90% required by Rule <br />4.10.4(3)(b), and contradicts the 90% requirement provided in subsection 6.5. Please <br />be aware that if a commitment to 95% is made in the permit, then that will be the <br />standard GCC will be required to meet. <br />c) Subsection 6.4 addresses the subsurface drainage system proposed for the West Waste <br />Bank. Trautner evaluated the permeability of the CMW to determine how much water <br />was likely to percolate into and through the waste bank. Rules 4.09.1(13) and <br />4.10.3(1) are pertinent to this waste bank project. Subdrains should need to be <br />constructed only to intercept water from springs or seeps and prevent it from <br />saturating the pile. Please note that in 4.10.3(1)(c), the subdrainage system is to be <br />covered to protect against entrance of surface water or leachate. Typically this is <br />accomplished by placing an impermeable membrane on top of the subdrainage <br />installation. <br />d) In the 5"' paragraph of 6.4, Trautner indicates that water was encountered in Test <br />Boring Six (TB -6) at a depth of 11 feet. Based on the Log for TB -6, this water was at <br />the approximate level of the bottom of the CMW Backfill. The relative location of the <br />six TBs is shown on Page 7 of Trautner. Is it possible that TB -6 may have been <br />drilled in the vicinity of the original natural stream channel, and that there is <br />subsurface water present that is not captured by the pipe inlet north of the highwall? <br />Please address whether this may be the case, and what impact this may or may not <br />have on the West Waste Bank. <br />e) Appendix C of Trautner was prepared by a sub - contractor, CDS Laboratories. Their <br />results indicate that subsurface water was found only in TB -1, not in TB -6 as Trautner <br />states. Please address this apparent contradiction on the location of water found in the <br />Test Borings. <br />f) Now that the CMW Backfill has been removed, will further examination and analysis <br />of the foundation material be required before construction of the West Waste Bank can <br />commence? Please address this question. <br />