A crucial step towards the safe re-entry of the Pike River Mine has been taken with the activation of a nitrogen-producing plant at the site.
The second drilling platform at the Pike River Mine near Greymouth. Photo: IAIN MCGREGOR / POOL / AFP
The Pike River Recovery Agency started the plant briefly yesterday.
The plant pushes nitrogen through the mine's workings to purge methane from the atmosphere, and is essential to the safe re-entry to the mine.
Agency chief operating officer Dinghy Pattinson said the plant had to be shut down after a brief period of operation yesterday.
"We started pumping nitrogen through pipes at the mine portal for a brief time before the weather closed in and we had to take our monitoring guys off the hill above the portal and shut the plant down.
"What we're looking at with the start-up is how long it takes to push nitrogen through the mine," Mr Pattinson said.
"We'll be running the plant every week day through to our Christmas closedown. All our operations are based on the success of this very important piece of hired equipment, so today was pretty important to the project."
The agency plans to fill the mine's tunnel with fresh air to allow re-entry.
The Pike River Mine workings and drift tunnel are currently full of methane, a gas that is dangerous when mixed with fresh air.
The methane first has to be purged from the mine workings and tunnel by flushing the site with nitrogen.
Mechanical superintendent Matt Coll pushed the button to start the plant yesterday.
"Matt's the one who will be managing the nitrogen plant throughout the re-entry and recovery operation, it's his baby from today," the agency's chief executive Dave Gawn said.
There was no fanfare surrounding the starting of the plant.
"Considering how important this is to our efforts, it's surprising how quiet it is. But it's definitely good to take this next step before Christmas," Mr Pattinson said.