VICTORIA -- The British Columbia government has issued a conditional permit allowing the Mount Polley mine to reopen, but with restrictions.

Mines Minister Bill Bennett says the permit is the first of three steps the mine must meet before being authorized to operate fully.

He says Mount Polley Mine Corp. must submit a long-term water treatment and discharge plan to the government by next June.

The tailings dam at the central B.C. mine breached last August, and 24 million cubic metres of mine waste and water gushed into area lakes and waterways.

An independent report concluded the spill was caused by poor dam design, which didn't account for drainage and erosion failures associated with glacial till beneath the pond.

The company estimates it will take about 30 days before it can start production, with up 220 workers on site.