Sealing Pike mine increasingly likely, police say

Police say any decision to seal the mine would be made at the 'highest political level'. Photo / NZPA

Sealing the Pike River Coal mine is increasingly likely as efforts to recover the bodies of 29 miners stall, police said.

Police said the environment inside the mine remained volatile and dangerous, despite machinery working around the clock to neutralise the mine.

Superintendent Gary Knowles said a site inspection by Canterbury University professor David Bell yesterday confirmed efforts to inertise the mine could take a "very long time".

Mr Knowles acknowledged sealing the mine was possible if the current machinery in operation could not inertise the mine.

A 'GAG' unit has been pumping water vapour into the Pike River mine shaft for weeks.

An Australian imported 20-tonne nitrogen machine has also been in use, but police said it had so far been too weak to fight the noxious fumes in the mine.

"We've been looking at every possible option and sealing the mine has always been among those options," Mr Knowles said.

Tasman Police District Communications Manager Barbara Dunn said sealing the mine was starting to look like the only option.

"We've always said if all else fails we will look at sealing the mine. We're getting closer to that point."

"It was never the first option but the longer it goes on the closer you get. It's been a month and things haven't gone our way."

Any decision to seal the mine would likely be made at the "highest political level", Ms Dunn said.

"We're in a holding pattern at the moment.

"It's incredibly unsafe to go in there and no-one knows what they're going to find."

Pike River Coal is set to present its plan for the recovery operation to Government tomorrow.

Torrential rain and high winds on the West Coast are hampering work at Pike River coal mine today.

The GAG machine was shut down for maintenance at 8am.

Shotcreteing work planned around the portal during the shutdown was unable to be completed due to the rain.

Police switched the the GAG unit back on just before 10am.

Gas levels rose when the machine was shut down overnight for maintenance on December 20.

No gas samples were able to be taken during the period of the shut down, police said.