The U.S. has approximately 17,000 abandoned underground mines and 56,000 abandoned surface mines.
The May 19 accident also injured two contractors and prompted the agency to issue roof and rib safety recommendations.
State mining and quarrying operations achieved zero fatalities and below-average injury rates for the 2025-2026 fiscal year.
MSHA urges miners to use gas detection equipment, adequate ventilation and appropriate respiratory protection.
A miner died from injuries sustained after falling through an unguarded opening on the fifth floor of a surface hoist structure.
Safety officials urge strict proximity controls and proper training after a fatal underground mining accident.