Untopping

nounStandard termMining

The process of removing overburden from an existing underground mine to convert it.

This mining method involves stripping away the surface rock and soil above an old underground operation. It transforms a former shaft or drift mine into an open-pit layout, allowing operators to safely extract remaining pillars, low-grade ore, or previously uneconomic seams using bulk surface equipment.

Heard on the job

We're untopping the old silver workings to get at the crown pillars left behind in the upper levels.