For three years the families of the 29 men killed in the Pike River Coal Mine explosion haven't been able to bury their loved ones.



Now, with the Government announcing a $7.2 million plan to re-enter the mine that has become their tomb, the relatives are holding out hope that proper funerals might someday be held.



"I may never get my son back, but other families might get their men," said Bernie Monk, a spokesman for most of the miners' families. His 23-year-old son, Michael, was last seen at the coalface helping someone just before it exploded.



"I'm just hoping like hell there's some bodies there. Until we go down there, then it will put all these theories to bed."



West Coast-Tasman MP Damien O'Connor said it was not for him to say whether a recovery team could get into the rest of the mine.



"It's a huge technical challenge, but one step at a time, that's all the families have asked for, and recovery of the drift can take place, as was originally explained over 18 months ago on a staged process."



"It's been an agonising wait," he added.

Prime Minister John Key said he thought there would be some relief at the decision but that there would "also be a lot of pain for those families because this is still a very delicate and tender issue for them and I understand that".



In announcing the $7.2m re-entry plan, Energy and Resources Minister Simon Bridges said the chance of finding bodily remains in the entrance tunnel was "slim".



However, rescuers would be ready to deal with human remains if found. If bodies were found, they could provide evidence for the police, Bridges said.



There was no guarantee that rescuers would ever be able to enter the rest of the mine.



"We do know there's been fires, there's been floods, there's been explosions so it has been and probably still is a very unstable environment," he said.



"That makes me personally sceptical about going further than the rockfall."



But some families believed a few bodies of those who died while fleeing the blast on November 19, 2010, might be retrieved from an unexplored 700-metre section of the tunnel.



A robot sent in soon afterwards reached only about 1.5 kilometres along the tunnel before breaking down. Its camera footage showed no bodies.



"We don't know if there is a frontrunner full of men [at the end of the tunnel]," Monk said.

Key said that exploring the tunnel could give the families some closure.

"We'll have an opportunity to see whether there are any men who were on the side of the rock fall nearest the entrance of the mine, there's been a view held by the families that may be the case, and that will at least give them closure one way or the other on that particular issue."



Re-entering the tunnel was also crucial to shed light on the blast's cause, Monk said.



Families hoped it would pave the way towards re-entering the mine's main workings, where most, if not all, of the men's bodies remained entombed.

But Key said that was unlikely.

Everything they had seen suggested getting into the mine or moving the rockfall would be a "Herculean step and I just don't think that's likely to happen", he said.

The Government believed if there was a way to get into the mine it would be under commercial entry because they would come at it from a different way, and with a different structure - though that would have to be feasible, credible and safe.

"And I'm just not convinced that that safety element could ever be agreed when it came to the main workings of the mine."

Solid Energy was not in the financial shape to undertake such a move nor was it likely to be in the near future, he said.

Mines Rescue workers were last in the mine on July 3, 2011, when they finished building a seal 170m along the tunnel and erected double steel doors at the mine's entrance.