A small surface excavation or entranceway leading into underground workings. Miners traditionally sank these shallow pits to prospect for veins or to provide ventilation and access to deeper tunnels. In older mining districts, these openings often follow the strike of a lode and can remain as hazardous, unmapped holes long after operations cease.
Heard on the job
Watch your step near the tree line, there's an old hatch hidden in the brush from the early lead workings.
Related terms
Adit
A horizontal or near-horizontal tunnel driven from the surface into a mountain or hillside to access an ore body.
Costean
A shallow trench dug through soil and loose dirt to expose the underlying bedrock and mineral veins.
Pothole
A shallow, vertical excavation dug to test for near-surface mineral deposits.