Canada still unsure on isotope reactor repair plan
By Allan Dowd
VANCOUVER, British Columbia (Reuters) - Repair crews are still trying to determine how to fix an aging Canadian nuclear reactor that produces a third of the world's medical isotope supply, officials said on Wednesday.
The Chalk River reactor in eastern Ontario has been out of operation since May 17 because of a heavy water leak, and officials say they cannot predict exactly when it can be restarted until a repair plan is completed.
They tentatively estimated in mid-May that the facility would be down for at least three months.
Atomic Energy of Canada Ltd said operators had removed the reactor's fuel, control and isotope rods, and reduced the rate of the leak -- which officials say does not pose a threat to the general public.
One test of the area of the reactor where the leak was discovered found significant weakening of the aluminum vessel's wall, but another test found no evidence of wall thinning, AECL said in a statement.
Additional testing was expected to take several weeks to complete, the government-owned company said. AECL said it was constructing a full-size mock-up of the vessel to help it develop a repair plan.
The unexpected shutdown of the 52-year-old reactor has sent hospitals in Canada and the United States scrambling to find replacement sources of medical isotopes, which have a short shelf life.
A medical isotope is a very small quantity of radioactive material used to perform nuclear medicine imaging tests. Isotopes are mixed with different solutions and injected into patients where they give off energy read by a special camera. Continued...