By Tim Mitchell, Features Editor
“That’s a little un-easing,” says a wide-eyed Kayti Bates upon learning of the existence of a nuclear reactor right below her feet. Bates is a fourth-year kinesiology student. In all her time studying at Dalhousie, like most staff and students, she hadn’t heard anything about it.
“I think it is quite a significant undermining thing that we don’t know,” she says. “I think more people would be interested to know exactly why it was put there, the history of it, and what it’s doing now.”
Dal has used the “SLOWPOKE” (Safe LOW POwer Critical Experiment) nuclear reactor for research since 1978. It can’t be used as a power supply, and it doesn’t contain enough uranium to make a bomb, but it is radioactive.
There are four similar nuclear reactors at other universities across Canada: Polytechnique in Montreal, the Royal Military College in Kingston, the University of Saskatchewan and the University of Alberta.
The Slowpoke nuclear reactor at Dal has been used by the chemistry department for Neutron Activation Analysis (NAA). It’s a process that can very accurately determine the concentration of elements that make up a varying number of solid or liquid objects. The benefit of this technology is that it doesn’t destroy any sample object that’s tested. What it involves is bombarding the nuclei of the atoms of materials with neutrons, making them radioactive, and then studying which atoms have become radioactive, and by how much.
The process is useful in determining the purity of metals, levels of arsenic in water, or even anthropologically investigating historical native trade routes by matching the substances of artefacts in different locations.
At the moment, it’s just sitting there, not being used for any kind of research. The university has decided to decommission the reactor – a process that will happen over, at least, the next two years.
“It’s in maintenance mode now. It’s basically warmed up once a week,” says Ray Ilson, director of environmental health and safety at Dal. He’s the man overseeing the decommissioning process.
“It’s really just used to test to make sure everything’s functioning properly, because when the decommissioning begins, we’ll need to run all the controls again. We just want to make sure everything’s ready to go.”
The decommissioning process will involve the collaboration of Dal’s board of governors, the Dalhousie University Community Committee, the city, the province, the Canadian Nuclear Safety Commission, as well as the Halifax Regional Police, fire departments, the hospitals and emergency medical teams, and HAZMAT (Hazardous Materials) – just in case anything goes wrong.
“That’s all part of the plan in case there was to be an incident and you had a person who was potentially contaminated,” says Ilson. “We’d have to take them to the hospital and treat them.”
The same model of nuclear reactor was used for research at the University of Toronto until it was decommissioned from 2000 to 2001. It was 25 years old. At the time, Ilson was manager of radiation protection services at U of T, and oversaw the decommissioning process.
“The defueling was completely uneventful,” he says. “The dismantling was uneventful. There were no doses (of radiation) received. There was some contamination that was discovered on decommissioning, which is what we’re doing now.”
Ilson says the good news was that it was discovered, and it was cleaned. He also says that during the decommissioning of the reactor at U of T, nobody went above the allowable limit of radiation exposure.
“The highest dose received was 3.2 per cent of the allowable limit.”
Ilson was the one exposed to that radiation.
“I was exposed to 1.6 millisieverts of radiation. I’m losing my hair, but nothing else,” Ilson says with a laugh.
A millisievert is a measurement of radiation exposure. The allowable limit of radiation exposure for members of the public is one millisievert per year according to Ilson.
“That’s for the man in the street, the barber, the taxi driver, anybody. For nuclear energy workers – people who work in radiation areas – the limit is 50 millisieverts in any given year.”
The Slowpoke reactor is located below the Life Sciences Centre. The facility itself is several rooms, and the reactor is in one of them. The fuel for the reactor, Uranium-235, is six metres below the floor, underwater in a concrete pool, and has concrete blocks on the surface. The facility is equipped with motion detectors, alarm systems and cameras. Security checks are routine.
Now Dal has decided to get rid of its nuclear reactor for a few reasons; Advancements in technology have made the reactor somewhat obsolete; the director of the facility, Dr. Amares Chatt, is retiring; and the cost of decommissioning the reactor in the future would only become more expensive.
“Labour costs go up,” says Ilson. “Transportation becomes more difficult if you think, the University of Toronto one was done in 2000 to 2001 – the actual decommissioning. That was prior to 9-11. Security has changed since then. It has become much more expensive – security of materials, storage, but also transportation. As well, getting rid of hazardous waste is now much more expensive, and the fuel and the parts and that are considered potentially hazardous waste. So the costs have gone up a lot.”
The decommissioning of the Slowpoke nuclear reactor will cost the university about $6 million dollars.
“The actual removal process is very, very safe,” says Ilson. “Essentially, when it’s decommissioned, (the facility) can be released for public use, in what’s called unrestricted use, so the university can move any other research they want there and you don’t have to worry about any radioactivity. There’s nothing left.”
The fuel from the reactor will be shipped back to the U.S. government. The reactor parts, because they’re radioactive, will be taken to at a long-term waste storage facility in Chalk River, Ontario.
“The whole process will be over in two years,” says Ilson.
He says he can’t get into specific dates of when everything will happen for security reasons.
“Right now the fuel is beneath six metres of water and surrounded by concrete all around it and on top and below it in alarmed rooms. The security requirements for that are less than when it’s sitting on the floor in the room. It’s much more accessible if a terrorist wanted it. So we don’t talk about when that will happen. Shipping would be a security concern so we don’t talk about shipping dates, or routes.”
For the decommissioning process, Ilson assures students, such as Bates, that they have nothing to worry about.
“Explode?” says Ilson. “No. Not that I know of. If it were to become uncovered, with no water, there would be radiation dose. But don’t forget it’s surrounded by concrete as well. The alarms would go off because they would start picking up the radiation. It’s automatically reloaded with water too. We would be called to investigate. There are backup electrical systems in the event of a power failure so to make sure those pumps work. They are tested routinely.”
“I would hope,” says Bates, “that if the school knows about a nuclear reactor being under our feet, that they would have taken all precautions.”
Recent Comments