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Course Outline

Abandoned and active mine sites represent a serious and extremely dangerous hazard to explorers, hikers, and OHV operators. Their numerous dangers are not always apparent. Active and abandoned mine sites have proven to be an irresistible—and sometimes deadly—draw for children and adults. Arizona residents operating OHVs have been known to fall into unmarked mine shafts, resulting in severe property damage, serious injuries and death.

  • Vertical shafts can be hundreds of feet deep. At the surface, they may be completely unprotected, hidden by vegetation or covered by rotting boards.
  • Horizontal openings, if seen and observable, may seem sturdy; but rotting timbers and unstable rock formations or soil built up around the edges make cave-ins a real danger. Darkness and debris add to the hazards.
  • Lethal concentrations of deadly gases (methane, carbon monoxide, carbon dioxide, and hydrogen sulfide) can accumulate in underground passages.
  • Unused or misfired explosives can become unstable and deadly. Vibrations from a touch or footfall can trigger an explosion.
  • Excavated vertical cliffs in open-pit mines and quarries can be unstable and prone to collapse.
  • Built-up hills of loose material in stockpiles or refuse heaps can easily collapse upon an unsuspecting OHV operator or hiker.
  • Water-filled quarries and pits often hide rock ledges, old machinery, and other hazards. The water can be deceptively deep or shallow and dangerously cold. Steep, slippery walls make exiting these swimming holes extremely difficult.

Any community with active or abandoned mines, quarries, or pits could become the scene of the next tragedy. For more information on the U.S. Labor Department’s “Stay Out—Stay Alive” program or to find out how to become a partner in this campaign, contact the Mine Safety and Health Administration (MSHA) at 202-693-9400 or visit the MSHA website.

For more information on safety around mine shafts, visit the MSHA website.

An abandoned mine shaft in Arizona
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