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Pillar Collapse Initiative

Since October 2020, four massive pillar collapses have occurred in limestone mines. Each was accompanied by a powerful air blast and the formation of a large surface sinkhole.  Fortunately they did not result in any injuries.  Another massive pillar collapse occurred in 2015, and in that instance three miners were seriously injured by the air blast.  All of these collapses occurred where floor mining, or benching, had substantially increased the height of the pillars.  Three of them occurred in “legacy” areas where mining was completed many years ago.  

MSHA has resources available to raise awareness and avoid these accidents at underground mines, particularly limestone mines, that can result in areas where benching has occurred.  Please use resources on this page to help you avoid the dangers of pillar collapses.

For questions regarding this initiative, or to register for one of the upcoming MSHA Stone Mine Pillar Collapse Seminars below, please contact  Seminars are being scheduled in coordination with MSHA Enforcement District offices.  If a seminar for your District has not been scheduled, please check back or email us.  When registering, please provide your full name, company or organization, phone number, and the date of the seminar you would like to attend. 

Upcoming Presentations/Seminars

None scheduled.

Past Events