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k y .. MAY 15, 2002, MID-TERM FOLLOW-UP ITEMS 2.05.6(6) Subsidence Survev. Subsidence Monitoring, and Subsidence Control Plan 16. Please update the narrative within Section IILA.7.j of the permit application as appropriate, on page III-21. Specifically, amend the statement in pazagraph 2, that "The effect of subsidence on the groundwater under Red Wash and Scullion Gulch is unpredictable and purely speculative", to address the effects documented by monitoring of the Red Wash alluvial wells. In addition, please amend the narrative of paragraph 4 to describe visual monitoring conducted and observed effects of longwall retreat mining on Panel LW-1B, beneath Scullion Gulch and Raven Park Reservoir. 17. Please amend the 2001 Annual Subsidence Report to include a discussion of the above referenced monitoring and observed effects, and include pertinent photographs, as specified in the permit text. Permit Organizational Items 18. Our copy of Permit Volume I, Section II.B., Geology, contains certain information not listed in the Section Table of Contents. This information begins following Table II.B-2 on page II.B-14, and includes Figure II.B-2 "Typical Cross Sections of the Coal Seams", Appendices 8 and 9 (pages II.B-23 through II.B-52), and descriptive and analytical information for a number of drill holes, on un-numbered pages following page I[.B-52. We notethat Appendices 8 and 9 aze referenced in the permit text on page II.B-6. Please address the appazent discrepancies between the Section Table of Contents and the actual contents described, and amend as appropriate. Also, please address the nature of the appazently missing Appendices 1 through 7 (pages II.B-15 through 22), and submit those pages if warranted. 19. Our Permit Volume 5 contains two distinctly different versions of Map 32 "Typical Drainage Structures Sections and Details" (Drawing No. D-346-C-109). One copy, labeled REV.2, has a copied certification by Don M. Williams, dated 2-20-81. The other copy, labeled REV. B, has a copied certification by Don M. Williams, dated 10/30/80. We assume the 1981 REV. 2 is the correct version, and that REV. B was replaced and can be discarded. Please advise as to whether this is in agreement with your permit copy. Also, our copy of REV.2 contains only ahand-written "Map 32" designation, and as noted the certification is not original. Please provide a properly labeled and certified Map 32. 20. Maps 43 through 46 are sheets 1 through 4 of "D Portal Area Site Restoration Plan". For Maps 43, 44, and 46, our permit copy contains two versions of each map, REV. C, with a revision date of 4/23/81, and REV. D, with a revision date of 10/13/81. The primary difference between the two versions appears to be that REV. C maps depict rock checks as the primary sediment control measures for the reclaimed D Portal Area, whereas REV. D maps depict incised sediment traps of specified volume. REV. C maps depict 12 rock checks on reclaimed Scullion channel and tributaries, whereas REV. D maps depict only three incised sediment traps, all on the main channel. Permit text on page V-16 references "loose rock check dams...shown on Maps 43, 44, and 46", and specifically references 3 such check dams. Three rock checks were indeed constructed during initial mine construction, downstream from the DP-1 pond embankment. It is possible that there was a lat@r revision of this map series that restored the loose rock check dam design referenced in the pennif text. Please review your permit Maps 43, 44 and 46, with respect to revision designations, revision dates, and sediment control specifications. If you have more recent revisions of the subject maps, or if you can otherwise clarify the apparent discrepancies, please advise. If the Revision D maps dated 10/13/81 represent the approved plan, then either the map design or the permit text, or both, will need to be amended to correspond.