WorkSafe has accepted a Pike River Recovery Agency regulatory exemption request which clears the way for the agency to begin work to recover the mine drift.
The WorkSafe release is available on their website.
Some questions and answers about the exemption application
How will you control the atmosphere in the mine drift when you remove the 170m barrier? Our Final Gas Management and Ventilation Plan (2019) provides for a number of ventilation control devices. The first, a Rocsil “plug” remotely inserted using boreholes close to the roof fall was completed in early November; with two confirmed ventilation control devices (VCD), (possibly more) – one inbye Pit Bottom in Stone and the second just outbye the Rocsil plug. One will be set up just inbye pit bottom in stone – this seal will provide a stable atmosphere for an extensive investigation of the hundreds of metres of tunnel and mining infrastructure housed in the pit bottom in stone area.
I want to understand in detail how you’re planning to ventilate the mine with fresh air? The two volumes of the Agency’s Ventilation and Gas Management Plan and Ventilation Report are on our website, search “ventilation” at www.pikeriverrecovery.govt.nz(external link). A further and final plan recently submitted to WorkSafe will shortly be posted on the website in the Documents section (after the gazetting of the WorkSafe announcement).
What were the documents submitted to WorkSafe on Friday 13 September?
- Ventilation and Gas Management Plan
- Entry and Exit Execution Plan
- Pike River Mine Drift Re-entry Geotechnical Assessment
- Application for exemption from reg 170 (4) (a) of the Health and Safety at Work Mining Operations and Quarrying Operations Regulations 2016
- Force vs Exhaust Ventilation Risk Assessment
- Mine Entry and Exit Risk Assessment
- Emergency Management Principal Control Plan
- Single Entry Principal Hazard Management Plan
These will be available on our website after gazetting, expected shortly.
Why did you need an exemption notice?
Regulation 170 (4) (a) of the Mining Operations and Quarrying Regulations 2016 requires that there must always be an ability for workers to escape from a mine in an intake airway. The Agency sought an exemption to use a process called ‘forced ventilation’ in which fresh air is forced by a fan to the working space through a duct and then the air flows back (called return air) through the roadway to the entrance of the mine.
WorkSafe undertook a detailed review of the Agency’s exemption request and determined that worker health and safety outcomes were at least equivalent to the outcome of adhering to the regulation itself. WorkSafe was satisfied that the PRRA request met all legislative requirements for the granting of an exemption.