Chalk River's NRU reactor scheduled to restart production in March
Six other repairs needed
Posted By SCHASE@THEDAILYOBSERVER.CA
Updated 2 months ago
The dormant NRU reactor at Atomic Energy of Canada Limited's Chalk River Laboratories is scheduled for restart and the resumption of medical isotope production by March 2010.
Technicians will also repair six other areas within the reactor's vessel that require attention, however, AECL officials reassured Renfrew County council Wednesday that work would not further delay bringing the NRU online.
"We'll return the reactor to safe, reliable operation in the first quarter of 2010," Dr. William Kupferschmidt, vice-president and general manager of AECL research and development, told county councillors. "That is our target. We are on target and we have every expectation we'll meet that target."
The National Research Universal reactor has been out of service since a small leak of heavy water was detected during routine maintenance last May.
An initial investigation found that the leak had occurred at the base of the reactor vessel.
In effecting repairs, technician crews have faced numerous challenges, Dr. Kupferschmidt added, including attempts to gain access to the leak, a high radiation field and other technical issues.
When the reactor was drained of its coolant, they identified six other locations where repairs would be required in the future to ensure the NRU's eration.
The decision was made to make those repairs at the same time.
Dr. Kupferschmidt said it is a complex operation which has required radiation protection technicians to design and built 25 specialized tools to make the repairs.
"This is not trivial science and technology," he said later. "This is a challenge."
To make those repairs, remote-operated cameras and tools will have to be lowered 30 feet into the interior of the vessel through a four and a half inch hole.
Specialized welding equipment has been assembled at the site with repairs expected to begin within weeks, said Dr. Kupferschmidt, who described the procedure as like a surgeon performing arthroscopic surgery.
Before the shutdown, the NRU reactor, through MDS Nordion, provided 80 per cent of isotopes used for medical diagnostic systems for the Canadian market and 40 per cent of the world's supply.
The isotope produced at Chalk River, technetium 99, is the radionuclide most commonly used to image the body in nuclear medicine scans.
It is preferred because of its short half life and because the emitted photon has an appropriate energy for imaging techniques.
While he expects market demand to return, Dr. Kupferschmidt said the shutdown has shown the medical community there are other suppliers available for isotopes.
"When the reactor is back in production, every isotope we produce will be very much wanted by the international community," he said. "Having a diversity of supply in various locations around the world is something we welcome."
Dr. Kupferschmidt pointed out to councillors that current plans to restructure AECL into two distinct units will not affect its position as Renfrew County's second largest employer.
The corporation has a direct economic impact of $210 million annually, including $14 million in local contracts. Since October 2007, 170 more employees have been added to Chalk River Laboratories.
"The economic benefits of this industry to the county is very substantial," he said.
AECL continues to develop CANDU reactors for export, he noted. The corporation recently submitted a bid to construct two new nuclear plants at the Ontario Power Generation site at Darlington, Ontario.
In addition, the Canadian Nuclear Safety Commission has completed phase two of a pre-project design review of Atomic Energy of Canada Limited's Advanced CANDU Reactor (ACR-1000) and concluded that there are no fundamental barriers to licensing the ACR-1000 in Canada.
Dr. Kupferschmidt said this will send an important message to potential interna - tional buyers adding it is currently building a CANDU 6 unit in Romania, while Jordan and China have expressed interest in purchasing Canadian nuclear reactors.
Sean Chase is a Daily Observer reporter
