The man leading a three person team into the Pike River mine says for him the operation is personal.
Dinghy Pattinson is the chief operating officer of the Pike River Recovery Agency and will head into the mine on Friday.
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It's not his first time inside it, he was part of a team that went 170m into the mine in 2011, leaving a note on the seal promising to get the men lost inside the mine out.
Pattinson told The AM Show he knew some of the men killed in the disaster.
"A lot of those people I've worked with over the years and they've worked for me so yeah there's a bit of personal stuff in there as well.
"That's why I took this job on in the first place, one of the reasons was it's coal mining, coal mining is in my blood and I'm a West Coaster."
The team won't make it to 170m on Friday and will instead focus on making sure further re-entries are safe.
"Everything you do has got risk with it, and it's how you manage that risk and over 16 months we've done a lot of planning, we've done a lot of risk assessments and we've got a lot of control on the situation," Pattinson said.
"It's really about monitoring the atmosphere, this whole project is really a ventilation project and it's about monitoring that atmosphere ahead of us and understanding what it's doing."
Twenty-nine men were killed after several explosions in the mine in November 2010. Pike River Coal Limited, Valley Longwall International and former mine CEO Peter Whittall all faced health and safety charges over the disaster.
Pike River Coal Limited and Valley Longwall International were both given fines, although Pike River Coal did not pay the full amount as it said it did not have the money.
Charges against Whittall were dropped in 2013 after he and Pike River Coal offered voluntary payments to the families. Prosecutors also said there was not enough evidence against Whittall.
Pattinson hopeful clues into what caused the explosions may still lie inside the mine, which remains a crime scene.
"We don't know what we'll find when we get up the end of that tunnel, but there's a lot of areas that have been unexamined... we may not in the end find the exact cause, but we may be able to eliminate some.
"The end of the drift is the most important part for us, to get up to that end and try and find out what went wrong."