Robot to enter tunnel once gas levels drop

The robot is a battery powered vehicle that is capable of being remotely operated. Photo / NZDF

Rescuers plan to send a Defence Force robot into the Pike River coal mine where 29 miners remain trapped once gas levels have dropped.

Gas samples being taken at the West Coast mine's main ventilation shaft were this afternoon still showing high levels of carbon dioxide and methane.

Tasman District police area commander Superintendent Gary Knowles told a media conference this morning that testing of gas levels in the mine was being carried out every half hour.

Mr Knowles said the rescue team remained on standby and were looking at what sections of the mine they could enter first.

"We've also been in close contact with the defence department and will be utilising if possible a robot on site to go into the tunnel when the opportunity arises," he said.

This afternoon, the New Zealand Defence force confirmed it was providing a specialist robot with a team to help police at the mine.

"The vehicle is able to perform reconnaissance, object retrieval and weapons delivery in human hazardous sites," it said in a statement.

It said the robot normally operated with four cameras, two for movement and two on the arm for weapon placement/aiming.

Pike River CEO Peter Whittall said the Defence Force robot would not be sent into the mine while there was any chance of it causing a spark.

The company's chairman had earlier said sending a robot into the mine could make the situation more dangerous.

The dilemma we have is that you can't operate in a gaseous environment like that with equipment that might be generating a spark and robots would be like that," John Dow told Radio New Zealand.

Mr Wittall said the team drilling overnight had done a "phenomenal job" and had reached 100 metres of the 162 metres they needed to drill to.

"In the last 10 metres before we get to the scene we will change drilling method to ensure we don't get any sparking," he said.

"We have opportunities to sample gas from that point. We will have an opportunity to put laser imaging gear down the hole.

"We will also be able to put down video camera information and look at anything we are able to see in the hole."

Mr Knowles said rescuers were also looking at getting a fibre optic cable so that the site could be monitored visually from base camp and planned to use seismic equipment on top of the ground to detect movement underground.

"We remain optimistic, but at the end of the day this is a search and recovery operation. We are going to go in and do our best to bring these guys to out."

The trapped miners:
Conrad Adams, 43 (Greymouth), Malcolm Campbell, 25 (Greymouth - Scottish), Glen Cruse, 35 (Cobden), Allan Dixon, 59 (Runanga), Zen Drew, 21 (Greymouth), Christopher Duggan, 31 (Greymouth), Joseph Dunbar, 17 (Greymouth), John Hale, 45 (Ruatapu), Daniel Herk, 36 (Runanga), David Hoggart, 33 (Foxton), Richard Holling, 41 (Blackball), Andrew Hurren, 32 (Greymouth), Jacobus 'Koos' Jonker, 47 (Coben - South African), William Joynson, 49 (Dunollie - Australian), Riki Keane, 28 (Greymouth), Terry Kitchin, 41 (Runanga), Samuel Mackie, 26 (Greymouth), Francis Marden, 42 (Runanga), Michael Monk, 23 (Greymouth), Stuart Mudge, 31 (Runanga), Kane Nieper, 33 (Greymouth), Peter O'Neill, 55 (Runanga), Milton Osborne, 54 (Ngahere), Brendon Palmer, 27 (Cobden), Benjamin Rockhouse, 21 (Greymouth), Peter Rodger, 40 (Greymouth - British), Blair Sims, 28 (Greymouth), Joshua Ufer 25 (Australia), Keith Valli, 62 (Winton).

Mr Knowles said after three days without contact the situation remained "grave" but he said drilling at the site was continuing and progress was going well.

He said the Department of Conservation, which owns the land where the mine is sited, had agreed to allow a 2.7km path up to the main ventilation site to be cut, making it easier to take air samples.

The site is currently only accessible by helicopter.

Mr Whittall said the blast was "a unique event".