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SAFETY PRECAUTIONS FOR PILLAR EXTKACTION <br />1. Pillar splits, lifts and slabs will not exceed twenty feet <br /> in width. <br />2. Two-rows of breaker timber or equivalent will be set on <br /> not more than five-foot centers across openings leading <br />• into pillared areas (gob) and such supports will be in- <br /> stalled before second mining is started. <br />3. Lift or radius timber will be set on not more than five- <br /> foot centers and be installed leading into pillar splits, <br /> slabs, or lifts. Radius timber leading into the pillar <br /> split will be installed prior to the second cut of the <br /> pillar split. The breaker timber may be part of the lift <br /> or radius timber. <br />4. The width of the roadway ]eading into a final pushout <br /> stump will not exceed a width of 16 feet and two rows of <br /> posts or equivalent will be set along each side of the <br /> roadway on not more than five-foot centers, if the final <br /> pushout stump is to be mined. Only one roadway leading <br /> into the final pushout stump will be permitted. <br />5. The installation of all timber support for pillar extrac- <br /> tion is typified by the accompanying drawing (page 14). <br />6. Pillaring methods shall eliminate pillar points that pro- <br /> ject inby the breakline. <br />7. Pillars will be mined in sequence unless roof, rib, or <br /> other conditions otherwise warrant. <br />8. Barriers will be mined in the same manner as that used for <br /> mining a pillar fender, see Page 19, Barrier Pillar Ex- <br /> traction. <br />9. Operators situated in cab shall not proceed inby permanent <br /> support, except when mining final push-out stumps; then <br /> the forward edge of the operator's canopy will not proceed <br /> inby permanent support. <br />10. During partial pillar recovery, if the initial pillars are <br /> mined in such a manner to eliminate long standing inter- <br /> sections and are intended to be split with a fully bolted <br /> roadway to result in two new pillars, the minimum result- <br /> ing pillar dimension will be 60 ft. centers or greater. <br /> Timbering during this splitting process would not be <br /> required as long as the splits broke into an existing <br /> totally supported roadway. If the split broke into prior <br /> gob, breaker timbers would be set to separate the split <br /> from the gob. Partial pillaring of the remaining blocks <br /> would be in accordance with drawings 14G through 14J, The <br /> splitting of the blocks is typically shown in Drawing 14K. <br />• Page Thirteen <br />Revised 05/11/79 <br />Revised 03/24/80 <br />Revised 06/04/80 <br />Revised 05/26/82 <br />Revised 02/04/83 <br />Revised 09/09/83 <br />