Department of Labor
Mine Safety and Health Administration
Bulldozer Slides Into Void at Stockpile
On January 29, 2003, at a surface mine in District 8, a Caterpillar D9R bulldozer slid back into a void located in the mine's raw-coal stockpile. The No. 3 and No. 4 feeders were feeding coal to the preparation plant at the time of the incident. Noticing very little coal coming from the No. 4 feeder, the plant operator increased the feed rate from the No. 3 feeder. As the bulldozer operator was pushing coal away from the stacker to allow for more storage space, the bulldozer fell backwards into the void located above the stockpile's No. 4 feeder. The bulldozer came to rest with its blade pointing upward, coal in its cab, and its back glass broken out. After opening the door and climbing out of the cab, the bulldozer operator contacted the plant operator, and, subsequently, the feeders were shutdown. Another bulldozer dug around the trapped machine for over an hour before the trapped bulldozer could be driven out. No injuries resulted from this incident, but the bulldozer received damage to the cab, a broken light, and a broken rear windshield.
- Provide training to every person that works on or near surge piles to alert them of the associated dangers and to the stipulations in the safety program.
- Indicate the location of feeder points with an overhead marker and provide an indicator to show if the feeder is in use.
- Use equipment with a fully enclosed cab equipped with high strength windows. Provide the window glass with structural support to prevent it from being pushed into the cab by outside pressure.
- Establish a system of communication so that the equipment operators working on the surge pile are aware of plans to open or close feeders. Every feeder should be installed with the ability to fully close and open the feeder gates.
- Foot traffic should not be allowed on surge piles. Never push material to an active feeder until a cone begins to form on the surface of the surge pile and always push perpendicular to the cone.
- Ensure that mine management is notified immediately if a cone does not form above an activated feeder. This is an indication that a void has formed above the feeder and corrective actions must be taken to eliminate the void.
- Self Contained Self Rescuers should be stored in bulldozer cabs.
This information was provided by concerned
miners in an effort to eliminate accidents. Accident or "close
call" information within District 8 may be shared by contacting
the MSHA office at (812) 882-7617.