A berm is a flat, engineered ledge left on the slope of a surface excavation or open-pit mine. These terraces catch falling rocks and debris, preventing them from tumbling down to the lower working levels. Berms also provide access routes for maintenance and help stabilize the overall highwall against catastrophic failure.
Heard on the job
Keep the haul truck away from the edge of the berm until the grader clears the loose rock.
Insider tip
A properly designed berm is usually wide enough to catch the expected volume of rockfall from the bench above, and operators are strictly forbidden from driving near its outer edge.
Also heard as
- catch bench
- terrace