In a major shakeup of Atomic Energy of Canada Ltd., the federal government will sell an equity stake in the commercial division that builds Candu nuclear reactors, CTV News has learned.

Ontario is currently looking to buy two new reactors to fill growing demand for power in the province, in a deal worth $28 billion. The federal government hopes that the private sector can make Candu reactors competitive with bids from France and the United States.

"It means an awful lot of jobs, particularly for laid-off autoworkers who will never get back on the assembly line," said CTV Ottawa Bureau Chief Robert Fife on Wednesday night.

It's also believed Ontario will eventually replace the aging NRU reactor at Chalk River, Ont., which provides at least a third of the world's medical isotopes.

"A senior official said the reactor is 52-years-old and not considered fixable, so they will have to build a new reactor," said Fife.

The problem-plagued Chalk River reactor was shut down May 15 for the third time in less than two years.

"Until all investigations are completed, it is premature at this point to set a definitive timeline for the return to service of the NRU reactor," AECL's Senior Vice-President and Chief Nuclear Officer, Bill Pilkington, said in a news release.

The recent shutdown of the reactor is "much worse" than its closure in November 2007, said the former president of the Canadian Nuclear Safety Commission.

There are no reactors overseas or in Canada that can act as a replacement for the National Research Universal reactor to maintain world isotope supplies, Linda Keen told CTV's Canada AM Wednesday.

"That ... makes it a much more serious problem not just short term but long term for Canadians and in fact for the world," she said.

At the time of the Nov. 18, 2007 closing, Keen said there were two replacement reactors.

There was a shutdown again in December, 2008, and another heavy-water leak in February, 2009.

Medical isotopes

The Chalk River facility makes a third of the world's supply of medical isotopes, such as molybdenum-99, or Mo-99. Isotopes are small quantities of radioactive material that are mixed with different solutions and injected into patients. They give off energy that is read by special cameras used in diagnostic tests.

Because the isotopes that the reactor produces have a half-life of just 66 hours, which refers to the time it takes half of the atoms in a sample to decay, the shutdown has quickly resulted in a shortage and that's affecting patients waiting for diagnostic tests.

Keen said medical personnel who she has spoken to say that they are spending less time with patients and more time worried about supply.

"They just really don't know what they can trust to come, so I think that's much worse than what they had 18 months," she said. "It's very unclear what the cause is and how long it's going to take."

Keen was fired from her job at CNSC after a political controversy erupted over the reactor' closure in late 2007, which caused a worldwide isotopes shortage.

The shutdown lasted nearly a month until Parliament voted to bypass the regulator's order.

AECL's then-chairman, Michael Burns, resigned after the fiasco, and the Conservative government later fired commission head Keen for her refusal to authorize the restart.

Keen said the current shutdown is also problematic because of the politicization of the commission that resulted from her being fired.

"When it starts up again that's really going to be the issue because the safety watchdog is no longer an independent watchdog."