Last December the Pike River Recovery Agency breached the mine tunnel’s 170-metre seal by making a ‘door’ as the next step in its $36 million project to re-enter the mine where 29 workers died in November 2010.
Back in 2011 a NZ Mines Rescue team built the barrier some 170 metres inside the drift.
Last month (January), after testing proved the air was stable, the 30 metre seal was demolished. The 2.3-kilometre drift was ventilated with fresh air so the party can advance up the rest of inclining drift.
Agency chief operating officer Dinghy Pattinson made the first break-through in December, after WorkSafe approved its Gas Management and Ventilation Plan (2019) that uses a number of ventilation control devices.
This plan had to be exempted from the current Mining Operations and Quarrying Regulations, 2016, which requires mine workers to be able to escape from a mine through an intake airway.
The agency sought an exemption to use a process called ‘forced ventilation’ whereby fresh air is forced by a fan to the working space and the air flows back through the roadway to the entrance of the mine. WorkSafe undertook a detailed review of the Agency’s exemption request before agreeing to it.
The exemption applies only to recovery of the 2.3 kilometre drift, and the phenolic plug recently installed at the end of the drift must remain in place throughout the recovery work, so many kilometres of working tunnels at the end of the drift will remain sealed.
A letter left by a NZ Mines Rescue team in 2011, with a promise to return, was found attached to the internal side of the barrier.
Family Reference Group members, Rowdy Durbridge and Sonya Rockhouse, were at the mine to witness the removal of the barrier.
Rowdy spotted something that looked out of place, and it turned out to be the missing letter, slightly worse for wear.
He was also the last person to see this letter outside of the Mines Rescue team, before it was placed at the seal, so it was an emotional moment for both Rowdy and Dinghy.