2008-05-15_REVISION - C1981008 (2)

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subsoil. Will the Bench 1 material be salvaged and replaced separately from the "Lift B" soil horizons, or will some thickness of unconsolidated overburden (as necessary to obtain a total 40" "subsoil" recovery thickness) be included in Lift B recovery operations. Please provide appropriate narrative clarification regarding delineation, recovery, and handling of rootzone material beneath Lift A, for the undisturbed portion of the Morgan property prime farmland. c) Narrative on page 2.04.9-23 indicates an average Lift A thickness of approximately 7.2 inches for the non-prime farmland soils north of BB Road, which seems reasonable based on the survey data for the dominant soil types. However, this does not correspond with Table 2.04.9-6 entries for the 16.67 acre "Lloyd Undisturbed" property and the 87.76 acre "WFC Undisturbed" property, both of which indicate an 18" Lift A thickness. This apparent inconsistency may be a semantic artifact, with "Lift A" being used to mean two different things (in one case referring to the A and upper B horizons, and in the other case referring to the top lift that would be removed, including A, B, and C horizons mixed). It would appear to be intended that an average 18" mixed soil layer would be recovered in a single lift from these areas, with a separate lower lift consisting of Bench 1 overburden material, but the wording is confusing. Please clarify the issues regarding salvage lifts and thicknesses (for soil horizons as well as underlying Bench 1 overburden) for the non-prime farmland areas, and ensure that tables, text, and maps are consistent. Please describe how the bottom of each lift will be identified for salvage in the field. Section 2.05.4(2)(d) Topsoil Redistribution 14. Narrative on page 2.05.4(2)(d)-6 describes overburden/interburden handling operations. The third paragraph describes the typical sequence, in which upper unconsolidated overburden is removed by shovel and trucks and placed into the adjacent mined out pit. The narrative actually references removal of the upper consolidated overburden, but we assume this is an error, since the upper overburden zone at New Horizon typically is unconsolidated; if the material were consolidated strata, it presumably would be initially drilled and blasted. Please clarify, and amend the wording as appropriate. 15. The narrative on page (d)-6 continues on to describe cast-blasting of consolidated strata beneath the upper zone, and removal of the lower-most overburden down to the coal seam by heavy equipment. Finally, the section includes discussion of special handling of Bench 1 overburden material, which would be undertaken as a mitigative measure to replace a suitable root zone, if problems are identified by the spoil monitoring plan. There is contradictory language regarding whether a four foot or 2-4 foot thickness would be replaced (four foot should be specified). A larger issue is that the discussion in this section is inconsistent with the description of typical overburden handling operations included in the Walsh Environmental letter in Attachment 2.05.4(2)(d)-1. In the attachment, it is stated that the upper unconsolidated "Bench 1" overburden material "is mechanically removed as a separate unit and is the last overburden unit to be placed over the reclaimed mine. As such there are generally several or more feet of the bench 1 material underlying replaced topsoil in the reclaimed areas." It is further stated that it was this Bench 1 material that was placed as the upper layer of overburden in the areas that were backfilled prior to February 2008, west of 2700 Road.