The stability of drilling chamber is an important facet to ensure the safe operation of VCR mining method.

In 2008 workers doing exploratory drilling for a geothermal plant reported that they had accidentally broken through to a shallow magma chamber near the Big Island's Kilauea volcano.

Rescue teams are drilling three additional boreholes more than 330 meters deep to ventilate toxic gases and reach a six-meter-wide chamber where officials believe the miners are.