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seam's structural contours. The seam dip's at a 3~ grade to the Southwest. The strike of the seam is S 55° E. For practical purposes, the upper Menefee seam may be considered flat or tabular. Most of the underground openings or entries are driven along some given angle to the true dip to take advantage of the property boundaries. This angle cannot be correlated to the cleat of the coal. The tight cleat allows the mine workings to be oriented without rib spalling problems arising. In addition, the lack of ground water seepage allows the workings to be layed without regard to drainage slopes. The main structural consideration of the mine layout is the width of the panels (number multiple entries) and the width of the entries. A panel width of 250 to 300 feet with five entries have proved satisfactory for devel- opment and pillar extraction. This width allows for room development upon retreat from the panel during pillar extraction. Stresses due to overburden thickness are minimal compared to deeper operating coal mines. Maximum over- • burden cover does not exceed 300 feet at any point, and the stress field seems to act in a vertical direction. No ground forces other than vertical have been observed by~inspection during mining operations. The shallow overburden cover would accommodate an increase in panel width or the number of multiple entries without undue stress problems. No major faults or slip plans cris-crossed the mine workings allowing for an even greater degree of optional orientation of the workings. The width of the openings have been limited to eighteen feet for control of the immediate roof (the thickness of the roof to the top of the resin bolting horizon). Thinly laminated shale and sandstone bedding comprise the immediate roof which must be supported with bolts or timber posts. Failure of the rock occurs as thin slabs dropping away when the roof is undercut. This failure can best be controlled by limiting the advance of depth of cut and by maintaining entry widths to eighteen feet or less to a minimum of fourteen feet. When roof conditions dictate fourteen feet of width, the pillar shape must be changed to a parallelogram shape to allow restricted machinery cutting CIO55-CL1tS.