Bob Walker revealed the information in his opening remarks to the Canadian Nuclear Safety Commission (CNSC) on Wednesday, some two years after Ottawa sold off the Crown corporation's Candu reactor to SNC-Lavalin.
Walker was before the regulator to discuss a recent performance review of Chalk River Labs northwest of Ottawa, site of the Candu reactor, which makes a large proportion of the world's medical isotopes
Walker told CNSC board members that the government is about to announce changes to how Chalk River will be run.
"It intends to ensure a sound commercial relationship between AECL and its customers and stakeholders who share appropriately in the costs and benefits," he said.
The restructuring comes as AECL is being forced to explain why it got two grades of "below expectation" in that performance review, in the categories of management system and fitness for service.
The problems are largely because Chalk River was built more than 50 years ago, and the buildings are getting old.
The reactor, known as the National Research Universal reactor, has been in service for decades and was shut down for months in recent years to repairs leaks in the vessel wall. That led to a worldwide shortage of the medical isotopes, used to diagnose heart problems and some cancers.
The reactor returned to service in 2010. But the performance review shows there are once again signs of corrosion, meaning the reactor could start leaking in the future.
In the same building that houses the reactor, chunks of plaster from the ceiling fell to the floor, because of water damage.
Randy Lesco, vice-president of operations and chief nuclear officer with AECL, says management is trying to do more than just fix the problems as they come up.
"We need to make sure that we have the appropriate programs in place to make sure we are preventing equipment issues, to being always in a fire-fighting mode," he told the CNSC board members.
In the end, AECL's biggest defence came from those who wrote the review, the staff with the CNSC.
"They are doing the right things. There isn't some magical solution that's suddenly going to deal with all the infrastructure problems on a 60-year-old site," said CNSC's Peter Elder.
AECL staff say the NRU reactor has consistently supplied isotopes for medical tests since it returned to service in 2010, and it will continue to do so until its licence expires in 2016.