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• 2.05.3(6) Overburden (continued) <br />be leveled to drill the blast hole pattern. A preliminary <br />designed drill pattern for both coal and overburden blasting is <br />shown on pages 1 and 2 of Exhibit L. The drill hole pattern for <br />coal blasting can be used in either phase of the sining <br />operation. Coal blast holes are shown to be only six (6) feet <br />deep because the coal bed has a shale parting about three (3) <br />feet below the top. In the initial sining area, where the <br />overburden to coal ratio is about equal the upper part of the <br />coal bed is probably oxidized and may require separate removal. <br />The coal in the two cores taken in this area showed a 25Ac loss <br />of recovery in each hole, and this loss is attributed to the <br />soft coal at the top of the bed. If this coal has no sarket <br />• value it will be returned to the pit for burial. If the coal <br />bed maintains sufficient Btu values to sarket the entire bed <br />without double shooting the drill holes for blasting will extend <br />to the bottom of the bed, and a small additional charge will be <br />added for lifting. <br />The overburden above the coal east of Engleville Gulch is <br />thicker and more abrupt than in the first phase of mining. <br />Consequently, a more resistant sandstone is expected to occur <br />and will require stronger blasting procedures as shown on page <br />three (3) of Exhibit L. All three blast hole designs show hole <br />size, depth, pounds of explosive material, ANFO, stemming, <br />millisecond delays, and drill hole configuration. Blasting <br />• designs are at this tine considered preliminary and will <br />4 <br />