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A discrepancy between the lithologic descriptions and laboratory textural analyses of strata !n close proximity to the Engleville • Seam has been resolved. The samples from hole 29-9, 86-100 feet and 29-4, 50-58 and 68-72 feet contained silt and sand sized coal particles which obscured the true lithology of the strata, 1. e. shale and shale with siltstone interbeds. The Interval 29-4, 68-72 feet is a clear example of the problem. The Snterval is comprised of two feet of shale and two feet of coal w(th little, If any, sand. The shale/siltstone description is further indicated by the geophysical log of 29-4. Although a geophyscial log is not available for hole 29-9, the close proximity of hole 29-4 permits a reasonable Interpretation of the llthologies of 29-9 In addition to those of 29-4. Consequentlty, the lithologic decrlptions shown on Exhibit 0 are appropriate and take priority over the laboratory textural analyses. The 'Discussion of Laboratory Results', below, reflects these conclusions. Hydrologic Aspects Both holes 29-9 and 29-4 were drilled with air. Water was encountered at a depth of 84 feet from ground level in 29-4, sixteen feet below the base of the Engleville seam. Hole 29-4 is down dip from the mine areas thereby suggesting that mining will • occur above the water table. Up dip, water is discharged from the base of the Engleville seam at groundwater station EMD, Exhibit AA. (Note that the water is piped from the coal outcrop to the EMD sampling station.) Water was not encountered in hole 29-9 which is generally on strike with the EMD discharge. According to the Previous Mine Map, Exhibit HH, hole 29-9 was drilled in an unmined area. If water is flowing along paths of least resistance through mine voids, this may in part, explain why the hole was dry. Again the data are Inconclusive. The water level in 29-4 was higher, compared to April, as a result of a wa~or precipitation event in Hay, 1988. Meanwhile the EMD discharge decreased from April to May despite three days of continual and often heavy precipitation Immediately preceding and during the measurement. The base water level, 29-4, and the EMD flow appear to be generally Independent and Ls further suggested by quality differences (see groundwater section). Discussion of Laboratory Results Non Coal Strata The overburden laboratory data, Appendix 3, was compared to the Hontana Department of State Lands Guideline for Suspect Levels in . Overburden Material currently used by Colorado MLRD to assess overburden. The Montana guideline ind[cated 'suspect levels' -7-