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the in.~l.og~ to the mine since the fault had first been <br />~`r'e~, The roof conditions were mapped first on <br />3/9/82. The object was to categorize the roof conditions <br />into dry (no latent moisture apparent), moist (roof was damp <br />and might drip, but there were not steady streams of water), <br />and wet (steady streams issued from cracks in the top coal <br />or holes drilled to determing quantity of top coal). The <br />roof conditions were then remapped on 3/15/82 and again on <br />3/20/82. The change in the position of the "w er frpnt" ~l <br />was remarkable over a short time span. Also, `e frofit ~; 7 <br />a~proximate`ly parallels the dip of the coal.' Exhibits C, D, <br />and E illustrate the results of the mapping program. <br />Extrapolation of Data from the Min <br />Although all holes that have been drilled from the surface <br />in the 2 West area have been logged, hole 81-07 was particularly <br />useful in that it includes not only the standard suite of <br />coal logs, but also neutron-neutron, sonic, differential/absolute <br />temperature, and resistivity logs. Once it became apparent 9 <br />(.' that Empire had ehanged seams when crossing the fault, and ~ ~ <br />`, that these occused. sand~.tip~-~D4~rL~' ~ris• sear, an. attenpt wad <br />~ ' made to determine the r~"soTSt~'~~S$~~ff~'ia'T''~''~C'h'is vni~ <br />Drilling records indicate that the sandstones in this area <br />make very little water, if any at all. The neutron log of <br />hole 81-07 indicates an average sandstone porosity of 15¢. <br />Upon physical inspection, the sandstone unit is comprised of <br />a series of fining upward units o:hich would effectively <br />limit vertical transmissivity. Horizontal transmissivity is <br />projected to be fairly good through the cleaner, cross <br />bedded portions of the unit. 'The core from UG-9, as well as~i~; <br />~(-the sonic log from 81-07 indicates abrindant fracturing " <br />within the sandstone. Secondary (fracture) permeability is <br />' proba ly the main means of migration and drainage in this `~ <br />~ unit. <br />~~The temperature log in hole 81-07 did not indicate a significant <br />inflow of water to the hole.3 A slightly exaggerated gradient <br />~•occurs, but no large change occurs in the curve opposite the <br />sandstone. <br />The geophysical logs of 81-07, as well as drilling records <br />from other holes in the area indicate that the sandstone <br />above the G seam seldom produces significant quantities of <br />water to drill holes. The presence of fracture permeability <br />is probably the only way to produce significant quantities <br />of water from this unit. The fault gouge appears to pct as <br />I~ a significant aquiclude to lateral migration of water; The~.~';, <br />sandstone above the G seam is essentially a perched aq,uifer,~{ ~ <br />~ in the area wherein the No. 5 Min® is operating. The areal` <br />extent of this sandstone, as defined by the limits of ,the:';.. ~ <br />two faults and the planned northern extent of works in the ~y <br />s <br />-3- <br />