Newshub can reveal the first member of the team who will enter the Pike River Mine will be one of the world's most experienced miners.
Tony Forster has been chosen by the families as their independent advisor and their eye underground.
"It is a massive privilege," he says.
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The Scotsman has done 46 years underground, including five major rescue and recovery operations.
"Unfortunately, circumstances have arisen where I have probably done it more than anyone else."
He was New Zealand's chief mining inspector after Pike River, and has always believed re-entry was safe. Now he'll return from a job in Australia to be part of it.
"It is both doable, and yes, it can be done safely."
Mr Forster will work alongside a small team of miners from the Pike River Recovery Agency, which is yet to be publicly named.
They will re-enter the 2300m access tunnel, and of most interest will be the unexplored area past 1600m which includes an electrical substation.
"It's like your fuse box at home," Mr Forster explains.
He says this will hold vital clues about what caused the explosion that can be assessed by police.
"It potentially holds lots of answers."
Mr Forster says answers are also needed about whether the second explosion - which ended all hope for the 29 men inside - was caused by the conveyor belt being turned on. This theory has been put forward by some of the families.
"It is a very rich field for the police to investigate," he says.
The re-entry mission will begin in February.