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New Horizon Mine TR-57 <br />2„a Adequacy Review <br />21-Oct-2008 <br />Page 7of15 <br />• Amended Table 2.04.9-6 appears to be reasonably consistent with <br />pertinent narrative and maps. <br />Item Resolved. <br />Section 2.05.4 2 d Topsoil Redistribution <br />14. Narrative on page 2.05.4(2)(d)-6 describes overburden/interburden handling <br />operations. The third paragraph describes the typical sequence, in which upper <br />unconsolidated overburden is removed by shovel and trucks and placed into the <br />adjacent mined out pit. The narrative actually references removal of the upper <br />consolidated overburden, but we assume this is an error, since the upper overburden <br />zone at New Horizon typically is unconsolidated; if the material were consolidated <br />strata, it presumably would be initially drilled and blasted. Please clarify, and amend <br />the wording as appropriate. <br />Item Resolved <br />15. The narrative on page (d)-6 continues on to describe cast-blasting of consolidated <br />strata beneath the upper zone, and removal of the lower-most overburden down to the <br />coal seam by heavy equipment. Finally, the section includes discussion of special <br />handling of Bench 1 overburden material, which would be undertaken as a mitigative <br />measure to replace a suitable root zone, if problems are identified by the spoil <br />monitoring plan. There is contradictory language regarding whether a four foot or 2- <br />4 foot thickness would be replaced (four foot should be specified). A larger issue is <br />that the discussion in this section is inconsistent with the description of typical <br />overburden handling operations included in the Walsh Environmental letter in <br />Attachment 2.05.4(2)(d)-1. In the attachment, it is stated that the upper <br />unconsolidated "Bench 1" overburden material "is mechanically removed as a <br />separate unit and is the last overburden unit to be placed over the reclaimed mine. As <br />such there are generally several or more feet of the bench 1 material underlying <br />replaced topsoil in the reclaimed areas." It is further stated that it was this Bench 1 <br />material that was placed as the upper layer of overburden in the areas that were <br />backfilled prior to February 2008, west of 2700 Road. <br />So, the cited Attachment (d)-1 discussion indicates that stripping and replacement of <br />Bench 1 overburden material would be (and has been) a standard operating practice, <br />whereas the permit narrative on page (d)-6 indicates that Bench 1 overburden is <br />typically hauled or blasted into the adjacent pit void, and that stripping and surface <br />replacement of the Bench 1 overburden (prior to soil replacement), is done only <br />where "special handling" is necessitated based on identification of unsuitable material <br />on the surface of the replaced spoils. <br />Please address this discrepancy, and amend the permit text or Attachment (d)-1 <br />description as warranted to be consistent and to accurately describe the overburden <br />handling operation as practiced in the past and proposed for current and future <br />operations. <br />7