"To the Pike River families – and New Zealand – we are returning."

That was Pike River Re-entry Minister Andrew Little's message this morning as he announced that re-entry to the Pike Rivere Mine drift would go ahead.

Speaking at an event at Parliament today, attended by some of the families who lost loved ones in the West Coast disaster 8 years ago, Little said he had carefully considered the advice of the Pike River Recovery Agency and had decided to proceed with one of three options presented for re-entry to the drift.

"On the basis of all the material I have been presented with, I am satisfied that there is now a safe plan for re-entry and recovery.

"Therefore, today I am announcing that I have approved the single entry plan. Re-entry of the Pike River mine drift will proceed," Little said.

Next Monday is the eighth anniversary of the tragedy at the mine. Two men survived but 29 died.

"Re-entry to the Pike River drift is an extraordinarily complex undertaking. This is a site which, even eight years after being the scene of multiple explosions and taking the lives of 29 men, poses major hazards. This has required incredibly robust planning," Little said.

The agency had recommended re-entering the drift via the existing entry. Cabinet this week approved an additional $14 million in funding, taking the total budget for the plan to $36m.

Little also considered the advice of independent adviser Rob Fyfe before making his decision on the options.

The Family Reference Group, which had its own experts, was also consulted throughout the process.

The first major task, breaching the 30m seal inside the drift, was likely to begin in February.

Little said much of the preparatory work had been done, such as making new emergency portal doors, restoring power and setting up a nitrogen plant to push out dangerous gases from the mine before oxygen is pumped in.

Little said there was always uncertainty in such projects but health and safety was paramount.

He quoted from the agency's report: "There is a lot we do not know and will not know until we are confronted with the situation as we find it underground. This will require agile thinking, the courage of all to say no if we are uncomfortable, the preparedness to reassess, reset and re-plan when necessary, and knowing when to call it 'quits'."

Little said that since the middle of this year, police had been actively involved in any re-entry plan so they could prepare for any forensic examination and victim identification.

He said the Government, and the three partners that made it up, committed to fulfilling the original promise made to the families, to do everything practicably possible to re-enter the drift and recover any remains and better understand the cause or causes or the original explosion on November 19, 2010.

Discussing the decision to go with the single entry option, Little said safety was paramount. Ventilation was a major consideration.

The other two options, either drilling a bore hole or another tunnel, would also have required a huge number of helicopter movements to remove spoil from the digging.

Sonya Rockhouse, Anna Osbourne and Bernie Monk, who all lost loved ones in the explosion and who have been fighting, alongside other families for re-entry, stood alongside Little holding photos of those they lost.

Monk and Rockhouse both lost a son each, and Osbourne lost her husband.

They were visibly emotional as Little announced his decision.

Osbourne said the families fought "really hard" for this day.

"This is a victory for the little people of New Zealand."

She said 29 men went to work that day and no one expected they would never see them again.

"It is a truly amazing day for the families today."

She said there needed to be changes in workplace health and safety, with more than 400 workplace deaths since the mine tragedy.

She thanked the late unionist Helen Kelly "from the bottom of our hearts".

Pike River Recovery Agency head Dave Gawn said there was still a lot not known and there was still a lot of work ahead.

"Safety comes first, then operations, but we are confident we can recover the drift and get this operation completed."

Little said he was confident in the advice he had received.

"This hasn't been a difficult decision because of that."

He was confident of the operation's success.

He said there was a possibility there would be bodies inside the drift and the effort should be made to find out.

Sonya Rockhouse said yesterday that she was feeling: "Very nervous, but I think it's going to be fine. It's a bit of a nervous time but it's fantastic."

Little received a report from the Pike River Recovery Agency late last month following nine months of work which identified three "safe and feasible" options to go into the drift.

The families of the 29 men killed in the disaster have been fighting for re-entry in the hope the remains of their loved ones can be recovered from the mine.

Little told the Herald last month he would make a final decision on whether it was even feasible to re-enter the drift after reading the report and receiving advice from Fyfe.

Little told a parliamentary committee in June it was possible re-entry could be started by the end of this year if a decision to go in was made, but he pulled back from that in October.

"I understand that is looking less likely now and it would be the early part of next year," he said.

"The Pike River Families and their representatives have been also included at every stage. The families have shown extraordinary patience and tenacity, and their contribution has been crucial," Little said.

Little had been expected to go to Cabinet to ask for $10-15 million on top of the up to $23m already budgeted for the recovery.

The agency identified three safe and feasible re-entry options to recover the drift:

• Drive a small tunnel to create a ventilation circuit
• Single entry, using the existing main drift access tunnel as the sole means to ventilate the main drift
• Single entry with a large-diameter borehole