A fire at Huckleberry Mine on June 6, 2012, sent four people to Lakes District Hospital by ambulance for treatment of smoke inhalation.
The copper and molybdenum mine is located 123 kilometres Southwest of Houston.
The mine's human resources specialist Wendy Curtis said the fire began about 4 p.m. when employees were restarting one of the regrind mills in the mill processing building.
According to Curtis, the clutch did not release, which then created friction, heat and smoke, resulting in a small fire.
She said the fire was extinguished within in a few minutes by Huckleberry Mine personnel. A total of 15 employees were evacuated from the mill.
The mill was cleared of smoke and back in production in an hour.
Of the four employees taken to Lakes District Hospital for treatment, one was released soon after and returned to work the same day and three were held for further observation. Those three have since been release from hospital.
Curtis said the incident has not impacted mine production.
The fire is under investigation by on site mine personnel and it has been reported to the Ministry of Mines.
With files from Houston Today