Further plans to complete the Pike River recovery have been released after a successful re-entry was made yesterday.
Since November 2016, the 2.3km drift tunnel had been sealed 30m from the portal entrance, with double airlock doors behind a wall of about 800mm of concrete.
Yesterday, Pike River Recovery Agency chief operating officer Dinghy Pattinson led officers through the doors to have a brief look inside.
"The walkway is still in good order. I would actually say there's no silt, it’s all pretty clear," says Pattinson.
“We could actually shine our lights ahead and see 170m wall and see the walls.”
The next steps
Officials say the next re-entry and recovery will be carried out by three agency teams.
The first team of miners will enter the drift, assessing its state in relation to ventilation, geotech and any other hazards that may need to be fixed.
"One of the first tasks is to re-establish the 170m barrier then establish access for vehicles including loaders, mobile roof bolting rigs that can re-support the roof and sides of the drift," officials said in a statement.
Any work to fix the drift to make it safe will then take place before a second forensically-focused mining team will enter to examine and remove any evidential material.
"Between the 30 metre seal and the previous seal at 170 metres, there are a few different structures designed to manage the constant flow of water, including two weirs, gabion baskets, a 'grizzly' which screens large rocks, and concrete blocks."
All exhibits will be handed to the police for processing.
"A third team will then enter, advancing the mining services, including gas monitoring, communications lines and ventilation bags which provide fresh air."
Diagram of the Pike River Mine. Source: File
Once complete, water management infrastructure will be re-established and a seal will be made at the portal.
The site will be refurbished to handover to the Department of Conservation (DOC).
DOC will seal the drift and boreholes not required for ongoing monitoring and the mine will revert to its inert methane atmosphere.
The plan is expected to be complete by June 2020.