Bore scopes will be installed in other panel intersections as part of the investigation to determine strata control process.

The incident was one of seven reported in the week to October 7 by the NSW Department of Industry.

In another incident, a notice was issued to an underground coal mine prohibiting mining in the longwall panel after a goaf fall resulted in uncontrolled emission of high levels of methane into the longwall.

The department is launching an investigation into the incident and has noted that action to comply with the prohibition notice has been completed.

Another incident reported by the department involved the ignition of flammable gas at the roof of a continuous miner operating the production face of a NSW coal mine.

This was caused by reduced seam height and failure to follow frictional ignition procedures, it said.