Underground teams are encouraged by the first forensic search of the operation to re-enter the Pike River Mine drift.
The area up to 170 metres has been traversed many times, but nothing of interest has been found.
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But Recovery Agency chief operating officer Dinghy Pattinson told Newshub they have a good system going.
"This is an area that was traversed on a daily basis from when the New Zealand Mines Rescue built the 170m seal in 2011, until 2016 when the seal was shifted from 170m to 30m."
Pattinson said there were no expectations that items of interest would be found in this area.
Police confirmed this was the case, he said on Tuesday.
A small team took part in a symbolic re-entry of Pike River Mine in late May, a few weeks after it was originally planned due to concerning oxygen readings from inside the mine.
"We have a good system running, involving briefings and debriefings," Pattinson said on Tuesday.
"Police will remain on site in support of the agency throughout the recovery project, and will continue to adopt an agile approach in the event of a critical find, such as the discovery of human remains.
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"This means that, in certain circumstances, police will consider deploying staff into the drift before it is fully recovered by the agency."
Twenty-nine men were killed in a series of explosions inside the mine in November 2010. The previous National Government had said the mine was too dangerous to enter.
But the current Labour Government disagreed and pledged during the 2017 election campaign to go back into the mine.