Rescuers cling to hope as drilling begins

Drilling equipment on its way to Pike River mine. Photo / Mark Mitchell

More than 48 hours after the methane explosion ripped through the Pike River coal mine, officials still don't know if the tunnel is safe.

Gas levels in the Pike Coal mine where 29 miners are trapped are "coming down", but are still fluctuating.

Police say a rescue team will not be allowed to enter until it is proven there is no risk of a second explosion.

Workers to drill hole to miners' location

Rescue staff have commenced drilling a 150m long hole this evening, 15cm in diameter so that more gas samples can be taken.

Today's developments
* A rig will drill a 150m hole to test air quality in the mine
* A full inquiry will be held after the emergency is resolved
* Two busloads of family members travel to the mine to speak with rescuers
* Gas levels in mine continue to trend down

Pike River chief executive Peter Whittall said drilling could take anywhere from 16 to 24 hours to complete.

"It's a difficult environment the drill is working in, it's high up on a mountain and it's drilling through hard rock," he said.

Once the work is finished on the hole, officials hope to drop a camera down it to discover the state of the mine following Friday's explosion.

Escaped miner speaks out

One of the miners who escaped the blast spoke about his experience today.

Coal cutter Russell Smith, who was working at the coal face, was one of the two employees to escape Friday's blast.

This evening he told 3 News he was very lucky. "I could have been blown to bits," he said.

Because he wasn't as far into the mine as the others, he said the explosion was not as strong when it hit.

He recalled seeing a flash before being knocked unconscious.

"My hat was ... torn off me," he told 3 News. "I remember struggling for breath."

He was found about 15m away from his vehicle and together with Daniel Rockhouse eventually found his way out of the mine.

Smith said he could still smell the smoke in his hair.

But his concern was for his colleagues stuck below ground. "There was a lot of young guys down there," he said.

They are our brothers - rescue chief

This afternoon Mines Rescue NZ general manager Trevor Watts revealed a Mines Rescue member was one of the men trapped underground, and said if there was the "slightest opportunity" to move in, the team would take it.

But he said conditions in the mine were still too dangerous to send men in.

Watts said that "the whole of [the trapped miners] are our brothers".

"The whole lot of them are our brothers and we know all of these guys there and if there was the slightest opportunity to go underground then we will be going."

The logistics of staging a rescue were "vast", involving a 2.5km walk to the first intersection on uphill, uneven terrain carrying 5-10kg of breathing equipment.

"So, this is not an easy, 'we can just throw the face masks on people and head into the mine in a hurry' because it's just not that simple.

"We have got to be certain that we are not going to compromise the safety of the miners we are trying to rescue and the rescue teams we will deploy underground."

There are six five-men rescue teams available, plus a seven-man team from New South Wales waiting in Christchurch if needed, and two Australian mines rescue officials are helping with planning.

He would not send rescuers to the area where miner Mr Rockhouse and Mr Russell Smith escaped from.

"It's still in the gun barrel. They are still in part of the mine. They are still in direct travel of an explosion path"

Mr Whittall clarified comments about what the temperature would be for the trapped miners.

He said an earlier statement that they would be in 25 degree heat was based on an assumption they were sitting in a fresh air source.

That would be different if they were near the site of a heat source or suspected fire still burning in the mine.

Support for families

Buses this morning took representatives from the families of the missing miners to the site for a short visit. The group returned at 12pm.

In a press conference this afternoon Mr Whittall said he'd spent much of the day with families, taking them up to the mine to speak with rescuers and emergency staff.

Mr Whittall said the trip was "successful", and that families were "very appreciative".