4th blast hits NZ coal mine

Large quantities of smoke and flames were seen shooting from the Pike River Coal mine’s vertical ventilation shaft after the blast.

Coal fire

“This smoke has changed, it’s no longer a gas fire, it’s obviously now a coal fire,” Pike River chief executive Peter Whittall told reporters. “Where that coal fire is or how big it is, we don’t know.”

The mine might have to be temporarily sealed to starve the fire of oxygen, Whittall said, without indicating how long it would take to kill the fire.

The move could seriously delay the recovery of the bodies, and Whittall said it was not the preferred option.

The explosions have dislodged a lot of coal, “so there’s a lot of fuel in the mine to burn,” he said. The worst-case scenario was that the actual coal seam would start to burn, he said.

A gas fire is relatively easy to put out, but a coal fire in a seam would be a “very different beast,” Whittall said. There were no injuries from the latest blast. People working near the mine entrance were moved away from the area for safety.

The 29 miners were trapped by the first blast on November 19 and declared dead after a massive second blast five days later.

A third explosion on Friday was fuelled by methane gas seeping into the mine. Police superintendent Dave Cliff said the latest explosion demonstrates the volatility of the mine environment, which has prevented any rescue workers from entering the mine since the first blast.