Pike River Recovery team breaks through 170m barrier

A new tag board was installed at the Pike River Mine, as a recovery team passed the 170m barrier for the first time since its 2011 establishment following the deadly explosion. Photo / Lee Harris

Today, a Pike River recovery team stepped further into the mine than ever before after its disastrous explosion in 2010.

A small team stepped through the 170m barrier into the Pike River Mine drift, the furthest yet since the barrier was erected by the New Zealand Mines Rescue Service in 2011.

Twenty-nine men were killed in an explosion at the mine and work is being carried out to re-enter the mine, with today's progress being a significant step for the team.

The 170m barrier from inside the Pike Rover mine drift. Today a team passed this barrier for the first time since it was established in 2011. Photo / Lee Harris

Chief Operating Officer Dinghy Pattinson said the crossing of the barrier was a "long time coming."

"We've been going in and out of the drift up to the 170m barrier since 21 May," he said.

"But last time I was on the other side of that 170, I was part of the Mines Rescue team looking for where to put a wall. And that was back in 2011.

"So today was pretty significant for me."

One of the recovery team members opens the first door in the 170m barrier, which was erected in 2011. Photo / Lee Harris

The group checked the tunnel for hazards, collected forensic evidence and inspected the walls and roof past the barrier.

Among those in today's team were Acting Underviewer Kirk Neilson, Mine Deputy Bryan Heslip, Geotechnical Engineer Chris (Rick) Lee and Pattinson.

Pattinson said the group's initial scan of the area did not reveal anything unexpected and that the drift looked "pretty good".

Over the next few months the recovery team will inch further along the 2.3km drift, carrying out forensic examinations.

"We know we'll have to do some work on the roof and ribs as soon as we get the barrier out of the way in January," Pattinson said.

Pipes at the 170m barrier, through which the Pike River Recovery Agency today passed, the first to do so since its 2011 establishment. Photo / Lee Harris

WorkSafe agreed that the Pike River Recovery Agency's plans to re-enter and recover the drift were safe two weeks ago.

"We've got a big job to undertake over coming months, and we wanted to get through if it was safe to do so before our Christmas close-down," Dinghy said.

The door into the mine will be shut and secured over the next few weeks, allowing the team to monitor the underground environment.

Work to remove the barrier will begin in the new year, Pattinson said.

When the 170m barrier is removed, the atmosphere in the mine drift will be controlled using a number of ventilation control devices (VCDs), as set out in the Recovery Agency's
Final Gas Management and Ventilation Plan.

In early November, the first VCD, a Roscil "plug," was remotely inserted using boreholes close to the roof fall.

Two other confirmed VCDs have also been inserted, although more may have been placed, Pattinson said.

One of these was just outbye the Rocsil plug.

Equipment at the Pike River Mine 170m barrier, built in 2011 after a deadly explosion the year before. Photo / Lee Harris

Another was an inbye pit bottom in stone, which will provide a stable atmosphere for an "extensive investigation" of the hundreds of metres of tunnel and mining infrastructure housed in the pit bottom in stone area, Pattinson said.

The project will take an unspecified amount of time, as it is event-driven and will be done safely in the face of "significant unknowns," he said.