2021-05-20_PERMIT FILE - C1981035 (12)

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power centers in the mine to 950/480VAC for the electrical equipment. Water used for dust suppression and motor cooling in the mine is supplied via a 4-6 inch diameter HDPE or aluminum pipe. Water is piped to the site via the Huntington Pond and Huntington Pipeline as per Division of Water Resources Decree 07CW100 (see Appendix 2(6). Ground water is generally absent and therefore spore water pressure does not contribute to instability of the roof, floor or pillars. In general, working conditions in the mine are good. STRUCTURAL CONSIDERATIONS OF THE MINE LAYOUT King II workings are confined to the upper Menefee (A) coal seam of the Menefee formation (Mesa Verde Group). The seam varies from about six to ten feet in thickness. The equipment used in the mine and the mining method itself is tailored to this seam's structural contours. The seam dips at a 3-6% grade to the Southwest. The strike of the seam is about S70°E. For specific details of the local geology see Section 2.04.6. For practical purposes the upper Menefee seam may be considered flat or tabular with no rolling of seam. Consequently, the layout of the mine workings is not dependent upon the steepness of the seam as it is upon the boundary lines of the coal leases. The panels or mining sections are laid out as shown on Map King II -005 to maximize the recovery of the leased coal. 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 laid out without regard to drainage slopes. The main structural consideration of the mine layout is the width of the panels (number of multiple entries) and the width of the entries. A panel width of 250 to 400 feet with five to seven entries has proved satisfactory for development 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 350 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 the panel width or the number of multiple entries without undue stress problems. No major faults or slip planes cross the mine workings allowing for an even greater degree of optional orientation of the workings. The widths of the openings are limited to twenty feet by MSHA for control of the immediate roof (the thickness of the roof to the top of the resin bolting horizon). GCC Energy, LLC King II Mine Section 2.05.3 Page 2 July 11, 2017 (RN -07)