As the weather changes in many parts of the country, MSHA is warning of freeze-thaw hazards as these cycles rapidly change ground and workplace conditions.
Water freezing in cracks expands and loosens material, increasing the risk of rock falls, highwall failures and unstable roadways. Ice, mud and poor traction make travel hazardous. Unrecognized freeze-thaw hazards have contributed to serious mining injuries and fatalities.
In its best practices, MSHA has encouraged mines to conduct examinations of highwalls, pit walls, banks, and slopes before work begins, after precipitation and freezing temperatures and during thaw periods.
It also stressed that mine sites should inspect for loose rock, sloughing ground, cracks and separations as well as overhangs and building or movement, and not to work or travel under unsupported or loose material. Finally, MSHA said, scale hazardous material from a safe location, barricade and post unsafe areas until corrected, maintain clean catch benches and rockfall areas, and make sure to update and follow all ground control plan procedures for the site.