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Dan Mathews -2- Mav 21, 2007 Additionally, we note that the second paragraph of Section 3.3.1, page 3-6 of the permit narrative, includes reference to map Figure 3.1-10. Figure 3.1-10 is being replaced with new Figure 2.2-7C, within TR-22. Please submit an amended page 3-6, revised to reference the new Figure 2.2-7C. CAM: The proposed language for the stipulation is acceptable. Enclosed is amended Page 3-6. 9. ORMS•• The Division had requested clarifications regarding waste disposa/area permanent ditches. Gariflcations addressing most of the Division's questions were provided. Response noted that 'Yhe difference between the interim mnfiguration and reUaimed configuration is the removal of Ditches K, and L, and CMP 1 and 3. " In reviewing the amended figures and design documentation, we note a couple apparent discrepancies that require explanation or revision. First lfie "Gob Pile Co/%ction and Diversion 100 year SEDC4D run -Fina/Reclamation ; incorporates Structure #9 (CMP#2). Based on revised Figure 2.2-7A and new Figure Z.2-7C, CMP #Z would also be removed for final reclamation, and as such, should be de%ted from the referenced SEDCAD run. Second/y, we have a question regarding the waste disposal area upland diversion, Ditch 'F". On 'As- Constructed"and "Interim"map Figures L2-6 and 2.2-6A, the ditch depicted flows from east to west, along the slope above (south o>) the disposal cel% However, on Fina/ reclamation map Figures 2.2-7A and 2.2-7C, designs appear to show (we believe incorredtyJ a two segment upper diversion, with one segment flowing west and one segment flowing east, from a 'drainage divide" There would appear to be no reason for such modification of Ditch "F; between the "Interim"and 'Fina/"mnflguratfons of the waste disposal site. P/ease address these apparent discrepandes and provide amended map figures and design documentation as warranted. CAM: Structure #9 (CMP-2) was deleted from the 100-year SEDCAD run -Final Reclamation. Please see attached pages M(vii)-53 & 55. The waste disposal area upland diversion Ditch F was amended on Figures 2.2-7A and 2.2-7C. 12. DRMS: Based on review of postmine topography depicted on Map Figures 3.1-5, 3.1-6, and 3.1-7, and stability cross-sections 18+00, 42+00, and 47+00 depicted on Map Figure 3.1-8, the Division made several observations and requested certain clarifications regarding the regrading plan for the portal access road. In their responses, operator noted that the grading plan would eliminate the existing cut slopes from the lower end of the road, up to the final, upper segment of the road beginning in the vicinity of Sta. 42+00. Along the major portion of the road up to Sta. 42+00 vicinity, the slopes would not be uniform; rather in several areas the backfill slopes would be concave, with steep upper segments and low gradient lower segments (as depicted on map Figures 3.1-5 and 3.1-6) Operator concurred with Division observation that along the upper-most segment of the road, backfill would not completely eliminate the existing cut slopes. Narrative on page 3-8 makes reference to utilization of "terraces" along this segment, 'to prevent excessive erosion and to provide long-term stability in cut and fill slopes. To the extent practicable, the terraces shall be rounded or reduced and shaped to conform the site to adjacent terrain.' These terrace features are depicted at the crest and toe of the reclamation backfill, in cross-sections for Stations 42+00 and 47+00. Operator stated that the reclamation plan would be amended to remove a sign cant quantity of coal fines from the mine bench area down to the waste disposal area. To reflect this change, the original 'blue line' TR-11 map and stability cross-section Figures 3.1-7 and 3.1-9 for the mine bench and upper road area were submitted to replace the corresponding map figures from TR-22 and the approved permit application, respectively.