Sill pillar collapse temporarily closes MAX Mine
By Timothy Schafer, The Nelson Daily
Two weeks after a stop work order by the Ministry of Energy, Mines and Petroleum Resources temporarily shut down the MAX Molybdenum Mine in Trout Lake was lifted, the mine has been closed again.
The molybdenum mine, located 120 kilometres north of Nelson on the tip of Trout Lake, was shut down Aug. 25 after wall sloughing was observed in the lower level of the mine.
On Tuesday, Sept. 21, production ceased and operations suspended when a sill pillar collapsed. No workers or mobile equipment were in the area at the time of the collapse.
The stability of the pillar had been the focus of ongoing observation, said Scott Broughton, president and CEO of the company.
“Geotechnical monitoring conducted by mine personnel successfully observed increased activity in this area on Sept. 20 and all mine personnel and mobile equipment were moved as a precaution,” he said in a release.
No other instability has been observed at this time.
Broughton said ventilation, pumping and other mine systems continue to function, allowing for inspection of the workings. Initial reports by mine personnel suggest the extent of the impact is limited to some timbered ventilation bulkheads and manways that are repairable.
In late August, sloughing occurred in the stope wall — a mining excavation in the form of a terrace of steps — and not in a manned access area of the mine, nor was there impact to the ramp or other parts of the mine.
An independent geotechnical report on the conditions of the underground mine was required before the order was lifted.
On Sept. 3 the geotechnical review found there were no issues with re-entering the mine and it could be re-opened and milling operations resumed Sept. 4.