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Rule 2.04.5 General Description of Geology and l~drol~y • 32. Under the interburden section, reference is made to the "minable N, 0, J, and L seams". Are these seams to be mined by the contour operation? Res~nse The O, N and L seams will be mined by the contour operation. No mining of the J seam is planned at this time. This has been conlected on revised page 2.04-8 in the interburden section of the geology text and revised page 10 of Exhibit 6. The R, Q, P, O and OI seams will be mined at the surface mine. This information has been added to revised page 9 of Exhibit 6. 33. Rule 2.04.6(3)(a)(iv) information should be provided for all portal face-up azeas to be affected within the first 5 year permit term. Please refer to this Rule for the specific information required. Re~onse Drill logs aze available in Appendix G-1 of Exhibit 6 describe the presence of subsurface water, lithology and texture at 1996 drilling locations MW-lA and MW-1 near the R1/R2 portal, MW-4 neaz the P3 portal, and MW-6 neaz the P1/P2 portal. Geochemistry • information was provided for all 1996 drilling, and is also found in Exhibit 6. This included roof (Table G-7) and floor (Table G-9) information on the coals at all water monitoring sites (MW-series) and at BH-1 and BH-2 (Tables G-3 and G-4) near portal P3. 34. Exhibit 6 text states "swell factors of 25 percent were detertnined by field observation and using percentages consistent with historical practices." What specific field observations or methods were used? What is meant by historical practices? Please expand this section of text as appropriate. e ns Density and slake durability testing was performed on the samples from BH-1 and BH-2. This information was correlated with active cast blasting and dozerjobs in eastern Kentucky. Observations at mines using similaz extraction techniques note that there is little compaction associated with cast blasting and dozer push operations. Data was collected from drill hole BH-2 located within the proposed mining azea. The data included the specific gravity and the Slake Durability Index (SDI) number for the specific strata recovered. The average density of the material is 140.25 lb/cu.ft. and ranged from 99.84 to 156.00 Ib/cu.ft. The SDI varied fmm 0.54 to 99.52. These densities and SDIs were compared to data collected at active surface mines using mining methods similaz to those • being proposed. This comparison indicated that a higher SDI material will swell approximately 40% when blasted using the proposed cast blasting techniques. Lower SDI 10