2003-06-30_PERMIT FILE - C1981010A (2)

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In general, the northern half of the proposed mine permit area (even numbered core holes) shows a predominance of shale-siltstone layers directly above the lowest mineable coal seam. Exceptions are the sandstone layers intermixed in holes CR216, 220 and 222. The southern portion of the proposed mine permit area shows the increased existence of sandstone layers directly above the mineable coal limit. CR217 reveals a layer of sandstone approximately sixty feet thick that is directly above the "O" coal seam. A similar condition also exists in CR221 above the "M" wal seam that will be mined. The entire proposed permit area shows a predominance of ashale-siltstone layer directly below the lowest mineable coal seam. This layer varies from approximately five to fifteen feet in thickness with few exceptions. However, this stratum will not be disturbed and consequently will not appear at the surface after mining. Overburden sampling at Trapper Mine identified strata that were shown to exhibit indicators of potential chemical and physical problems. As stated previously in this section, high clay content overburden tends to be associated with high ESP values. Overburden up to 50 feet above the lowest mineable wal seams generally ends up at the surface and becomes part of the subsoil for supporting vegetation. Appropriate • overburden core sample analysis and core locations are available in Appendix I and provide a basis to compare suspect (high SAR and Clay) overburden holes with corresponding reclaimed areas in which these materials were spoiled. Focusing on what was considered to be the potential spoil problem area, Trapper Mine proposed (1988) to abandon its program for sampling in-place overburden since past sampling and analysis had provided adequate baseline information. In the alternative, spoil sampling was initially proposed to be conducted on all mine spoil areas. However, evaluation of past spoil and overburden data indicated that potential spoil problems only existed in Ashmore pit's advance. Consequently, Trapper Mine proposed to only sample regraded spoil in Ashmore pit and report the results to the Division by March 15 (Appendix W Annual Report). Spoil sampling procedures were as follows: composite samples were taken on 50 to 100 foot centers for each mapping unit. Mapping units were determined by visual and textural differences of surface spoils. A minimum sampling density of approximately one sample per five acres of reclaim area was accomplished. Each sample was comprised of a composite obtained from at least one foot into the spoil material. Samples were analyzed in accordance with parameters described in Table 2.7-2a. Final mapping units and sampling locations were presented on maps provided in Appendix W Annual Reports. Each map unit was identified by the year sampled, texture, and lab analysis number(s). During the review of permit revision PR-3, the Division recommended that Flintlock Pit be added to the spo(I sampling program. Criteria, procedures, and reporting were as previously discussed for the Ashmore pit area. L J 2-361a Rc;vlsitxt: r.?-B9 App~w~: to rY(ot