Grey District Mayor Tony Kokshoorn is calling for Pike River to be made into an opencast coal mine, amid efforts to keep the 114 skilled miners made redundant today on the West Coast.

Many suppliers may never be paid back for giving to the recovery operation at Pike River Coal mine, the Grey District Mayor says.

Receivers for Pike River Coal are making 114 of its employees redundant immediately.

The families of the 29 workers who died in the Pike River mine are calling on the Govt to fund the recovery operation.

An Australian mine safety expert and a former senior NZ public servant have been named as Royal Commissioners in the Pike River mine tragedy inquiry.

State-owned coal miner Solid Energy's plans to turn low-grade Southland lignite coal deposits into massive new industries make no sense and the coal should remain in the ground, says the Parliamentary Commissioner for the Environment.

Pike River Coal will have to reduce its workforce when it is ready to re-establish operations, but CEO Peter Whittall says reports of possible receivership were "extremely premature".

There are fresh hopes firefighters will soon be able to cap a key ventilation shaft at the Pike River mine, after the disappearance of flames from the vent.

Rio Tinto Group, the world's third-largest mining company, has made a A$3.5 billion ($4.53 billion) takeover proposal for Riversdale Mining, which is developing coal mines in Africa.

Pike River has rejected claims management was not approachable for staff with safety concerns before the November 19 blast.

Firefighters were last night battling to cool the extremely hot concrete pad around the Pike River mine vent shaft.