Grey District Mayor Tony Kokshoorn has again called for an open cast mine at Pike River to extract around $6 billion of coal to boost the West Coast economy.

The mine has been closed since November 19 after a series of blasts killed 29 miners, whose bodies remain trapped in the mine. Pike River Coal is in receivership.

Mr Kokshoorn told Radio New Zealand an open cast mine would provide welcome employment and economic opportunities to the West Coast and New Zealand.

"If we want to remain a wealthier country we need to get that coal."

Open cast mining at the site - on conservation land in the Paparoa Ranges - would involve removing 150m of rock to reach the coal seam.

Mr Kokshoorn said the council could hand over land to be placed in conservation estate so that it could be dug up, which he said would provide a net gain for the conservation estate.

"It could be a win-win," he said.

Energy Minister Gerry Brownlee has not ruled out the idea, but said he would await Royal Commission findings into the disaster.