Three workers were hurt after ground apparently shifted at an underground limestone mine in western Pennsylvania causing a rush of air through the mine’s entrance, according to a report by the Associated Press.
Read MoreTag: air blast
Vari-Stem Contains Explosive Energy Within Rock Mass
Vari-Stem Plugs work by creating a blocking effect within the drill hole by wedging the stemming material between the drill hole wall and plug. Upon detonation of the explosives, the plug is forced upward into the stemming material and “locks up.” The explosive gases and energy are prevented from traveling (venting) up through the drill hole, and instead are contained…
Read More