The head of Canada's nuclear agency, Atomic Energy of Canada Limited, hinted Thursday the aging nuclear reactor at Chalk River, Ont., could be shut down for longer than first estimated.
AECL president Hugh MacDiarmid told a Commons committee it's "optimistic" that the NRU reactor will return to service in three months as originally predicted.
MacDiarmid said the company will know more when it finishes its inspections in a few weeks.
The reactor produces more than a third of the world supply of medical isotopes used in diagnostic scans.
The company shut down the 52-year-old reactor on May 15 after a heavy-water leak.
New images released by AECL show technicians assessing the reactor, using cameras to inspect the external wall.
AECL says it has begun removing fuel rods from the NRU reactor as part of the process to repair the reactor. Rod removal will take weeks to complete, at which a clearer assessment can be made as to when the reactor can return to service.
Natural Resources Minister Lisa Raitt said the resulting shortage of medical isotopes will be eased at least partly by increased production elsewhere.
But opposition critics rejected that as "false assurances."
In the Commons, Raitt said progress has been made in global discussions to pick up the slack left by the Chalk River shutdown.
Raitt said a reactor in the Netherlands has agreed to increase its supply of medical isotopes by at least 50 per cent. And, she said, an Australian reactor is now expected to come on line "much quicker than they had expected."
But opposition critics said the so-called progress won't make any difference to Canadian cancer patients forced to wait for crucial diagnostic tests.
Liberal environment critic David McGuinty said the Dutch reactor is already leaking and is scheduled to be shut down for at least six months starting in January.
"How is it possible that we're going to get 50 per cent of our isotope supply from a reactor which is on the verge of closing down for at least six months? I tell you, they're making it up as they go along," McGuinty said.
"This is a crisis. They're trying to cover it up."
With files from The Canadian Press
