Highwall Hazards On August 30, 2003 a mobile equipment operator was injured while working at a surface coal mine. The miner was operating a Hitachi hydraulic shovel when a 35-foot wide by 35-foot high section of the highwall toppled onto the operatorís cab, pinning him inside. The victim was removed from the shovel and transported to a hospital where he was treated and released.
Highwall Stability Safety Alert Winter months can bring drastic changes to the stability of highwalls due to freezing and thawing. Water accumulates in crevices of rocks and then freezes. The ice acts as a wedge to expand the crevice opening. The ice thaws and the cycle begins again which in turn compromises the stability of the highwall that can result in highwall failure.