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Stone Mine Massive Pillar Collapses - Safety Alert

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Four pillar mine collapsesin a short period of time.
width to height ratio example showing the pillar density, it shows 30'/50' which equals .06


Best Practices

Address Potential for Future Massive Pillar Collapses:

•    Properly design pillars for benching (width-to-height ratio >0.8 and assess pillar stability)
•    Maintain planned dimensions
•    Account for pillar raveling or blasting overbreak
•    Assess geologic features in the pillar

Identify At-Risk Areas:

•    Recognize signs, such as spalling and hourglassing, that may indicate a pillar is overstressed
•    Assess benched areas and verify pillar dimensions
•    Evaluate potential air blast pathways
•    Reduce exposure of miners to airpaths
•    Protect mine infrastructure