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~~ '. ~`~~} 2.04.6 and 2.04.7 ~ Geology and Hydro logy~Descriptiori ' 1. From geological cross-sections on Map d13, it appears that a small portion ' of the Lennox Coal Seam overlies part of the area to be surface mined. The applicant should describe the extent of this seam overlying the proposed surface mining area and indicate whether this seam is mineable. C ~C1s If the applicant is not planning to recover the Lennox, justification mus ed ' be provided and a chemical analysis submitted for this seam. Response: Justification for not mining Lennox - As shown on Map 2a, Energy Mine No. 3 Geology, and Map 3, Geologic Cross-Sections A,B, 6 C, there is a very small portion of coal in the Lennox seam that lies within the boundary of the mine plan. Significant problems with quantity and quality prevent this seam ' from being mined. The Lennox seam is split into two beds separated by approxi- mately 6.8 feet of rock. The upper bed is approximately 1.4 feet thick and the lower bed is approximately 1.2 feet thick. In-place reserves of the Lennox are approximately 14,600 tons. This figure is computed on the basis of 2.4 acres of the upper seam and 4.1 acres of the lower seam. A conversion factor of 1770 ' tons per acre foot was used. To calculate Lennox reserves in the mineable category, coal under less than 25 feet of cover was excluded from the in-place ' reserves due to weathering. Given this, no mineable coal exists in the upper seam and, using 1.8 acres, approximately 3800 mineable tons exist in the lower seam. Because the lower seam is so thin, 1.2 feet, mining would be most diffi- cult. However, assuming a 50% recovery factor for such a thin seam, recover- able reserves would be approximately 1900 tons. There are two problems with respect to quality. First, the Lennox in this area is of low heating value. Although no laboratory analyses are available, density information from geophysical logs indicates t e heating value to be approximately 9700 BTU. Because the seam is so thin, the as-mined heating value would probably drop to about 7100 BTU with an extremely high ash content. The second problem with Lennox quality is its traditional high sulfur content. An analysis from the Eckman Park area, shown in Exhibit 21a, Lennox Analysis, indi- cates a sulfur content of 2.80 Y, _, ~ -3- 1 ~ ).