Cleanup "depends on how much of the tailings they have to remove," says Scott Dunbar, associate professor of engineering at the University of British Columbia.

Just moving the tailings back into the pond would be about $20 million, he says, adding, "There's also rehabilitation measures, such as reshaping river channels and reseeding or replanting. In addition, they will have to monitor the river, land and lakes for quite some time."

In a statement, Imperial said it is "too early to estimate the total costs of remediation and reclamation. We believe the costs can be managed over time."

Aleksandra Bukacheva, analyst at BMO Capital Markets, Toronto, put an estimate at $200 million, without counting legal costs, calling it an "extremely negative" event.

The mine shutdown will cut Imperial profits because the mine makes up about 80% of earnings, she said in a note to clients. Shares have dropped to less than $9 from $16.80 before the spill.

The province's Professional Employees Association (PEA) is calling for hiring more inspectors in its campaign to call attention to the number of scientists no longer on the public payroll.

Its study, released in March, shows a 24% cutback in staff professionals since 2001. "We believe the government [is] putting public safety at risk and failing to appropriately steward public resources," says Scott McCannell, PEA executive director. The number of mining inspections dropped by about half between 2001 and 2012, he says.

Public trust is especially tenuous among the First Nations people who fear their sacred lakes and rivers are being sullied for money, says Richard Holmes, fisheries biologist and head of Likely-based Cariboo Envirotech Ltd.

He calls the spill a "real and polarizing issue," both in the province and nationwide. "The world is watching, and I hope they get the cleanup done correctly," he says. "The tailings storage dam has failed, but let's not fail in the cleanup."