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The Wadge Seam ranges in thickness from 8.5 feet to 11.5 feet throughout most of the area to be mined, and <br />• reaches a maximum of 13.5 feet in the southwest portion (see Map 11, Wadge Seam Isopach). High heating <br />values and volatile content place the Wadge Seam in a High Volatile, Group C, Bituminous Coal <br />classification (see Exhibit 10, Geochemical Analysis of Wadge Seam). The lower one foot of the Wadge <br />Seam is comprised of a high ash "bony coal" which is relatively uniform across the mine property This unit <br />commonly forms a gradational contact with the underlying carbonaceous mud stone. No significant amounts <br />of acid - forming, toxic - forming, or alkalinity - producing materials have been identified within the coal seam. <br />Lateral continuity and consistency of the Wadge seam is good to excellent. Sample locations are illustrated <br />on Map 12, Sample Locations, and Lithologic logs of these drill holes are included in Exhibit 12, Lithologic <br />Core Logs. <br />Lithologic characteristics, physical properties, and chemical analyses of the stratum immediately above (0- <br />10') and immediately below (0 -5') the coal seam are presented in Table 20B, Geochemical Analysis of Roof <br />Material - EMD, and Table 20c, Geochemical Analysis of Floor Material - EMD.. Samples were analyzed <br />for all soluble salts and toxic elements listed in the "Guidelines for the Collection of Baseline Water Quality <br />and Overburden Geochemistry Data" (CMLRD, 1982). <br />Past experience has shown that out of seam dilution is the main contribution to unmarketable quality. Over <br />the past three years, methods and equipment have been developed to limit the amount of out of seam dilution <br />that occurs during longwall mining. Twentymile's Foidel Creek underground mine has invested in equipment <br />to accurately measure inches of roof coal (gamma ray detector) and automatic monitor run of mine ash on the <br />portal belt. <br />The monitoring process, along with a detailed underground seam sampling and mapping program, allows <br />mining equipment operators to try and selectively cut the coal horizon on the longwall face. Selective <br />cutting leaves approximately 0.70 -foot of roof coal to control 0.25 to 0.65 -foot of soft friable shale in the <br />• immediate roof contact. Additional efforts are currently being made to control floor shale dilution by leaving <br />0.35 to 0.60 -foot of hard bony coal to keep the massive shearer from gouging or cutting floor rock. <br />Directly below the Wadge Seam in the planned mine area is a persistent and laterally continuous layer of <br />material composed of clay -sized particles called underclay. Beneath this underclay is a zone of alternating <br />thick shales, claystones, siltstones, and intermittent lenticular sandstones. the shales are generally continuos <br />and the sandstones discontinuous. Near the base of this zone of alternating beds is the Wolf Creek Seam. <br />Within the planned mine area, the Wolf Creek Seam splits into two or more separate coalbeds. The <br />combined total seam thickness ranges from zero to twelve feet and displays extremely poor lateral continuity. <br />The Wolf Creek seam is separated from the underlying massive Trout Creek Sandstone by alternating beds <br />consisting mostly of shale. Similar to the Twentymile Sandstone, the Trout Creek Sandstone is fine- grained <br />and is a key marker bed. It defines the bottom of the Williams Fork Formation and the top of the Illes <br />Formation. Immediately beneath the Trout Creek Sandstone is a massive marine shale. <br />MINE FAULTS <br />Technically, the fault encountered (July 1995) in the East Mining District's 9th Right gate road (Cross <br />Section A - A'), would best be described as a very localized series of left lateral (sinistral) strike -slip faults <br />that scissors to produce small displacements. Exhibit 9B, 9 Right Gateroad Faulting, presents a varied <br />depiction of the faulting. Regional seismic data suggest that the minor fault could be the result of very small <br />oblique -slip movements related to deeper thrust faults (ramps) that do not reach the shallower Wadge coal <br />seam horizon (RE: Seismic lines Getty 1982 and Amoco 1985). The 9th Right fault appears to be part of a <br />series of northwest- stri king minor lateral faults. The second mine fault in the series was encountered <br />• (August 1989) in the 5th Left gate development within the West Mining District (Map 5, Surface Geology) <br />APPROVED JUN 2 8 2000 <br />PR 99 -05 2.04 -15 03/28/00 <br />