Currently, stockpiles of potassium iodide (KI) pills are kept in pharmacies and community centres for people who live within 10 kilometres of the Pickering, Darlington, and Bruce nuclear stations.
But the Canadian Nuclear Safety Commission updated regulations last Friday to require that the pills be distributed to all homes, businesses and institutions within the "designated plume exposure planning zone" by December 2015.
Officials are trying to determine exactly how to get everyone in the 10-km zones a supply of KI pills, which are used to protect the thyroid gland from radioactive iodine in the "highly unlikely" event of an accident that causes a leak of radioactive material, said Neal Kelly of Ontario Power Generation.
"All of the parties, the utilities, the municipalities, the province and the regulator are working to figure out how to meet that deadline," Kelly said in an interview.
OPG, the government-owned utility that operates Pickering and Darlington, along with privately run Bruce Power, which operates the Bruce nuclear station, are responsible for buying enough KI pills for everyone living near the plants, but it'll be up to the municipalities to distribute them, added Kelly.
"There will be significant distribution costs because you'll have to have a lot of communications, a significant education campaign plus a way to deliver these pills to each person," he said.
OPG purchased 800,000 of the pills in 2012 to replenish the stockpiles meant for people living near the Darlington and Pickering stations, an area stretching from Clarington to Scarborough in east Toronto.
Ontario is lagging behind New Brunswick and Quebec, which have already done mass distribution of the KI pills, said Green Party Leader Mike Schreiner.
"It's something that environmental organizations have been asking for but the government's been dragging its feet, and now the CNSC has stepped into provincial jurisdiction to some extent and said: 'you have to do this,'" said Schreiner.
"For me, what it really highlights is the government has been very reckless in shirking its responsibility to update its nuclear emergency plan since Fukushima."
A tsunami triggered by an earthquake slammed into the Fukushima power plant in Japan in 2011, releasing radioactive particles into the atmosphere and ocean in what is called the worst nuclear accident since the 1986 Chernobyl disaster in Ukraine.
Greenpeace Canada criticized Emergency Management Ontario for blocking an attempt by the Nuclear Safety Commission for "selective pre-distribution" of the KI pills to people outside the 10-kilometre primary zone.
"Given the population density around the Pickering and Darlington reactors, Greenpeace submits there is a need to examine how long it would take to distribute KI beyond the 10-km zone," said spokesman Shawn-Patrick Stensil.
"Indeed, people were evacuated well beyond a 20-km zone around Fukushima."
The Green Party and Greenpeace want Ontario to expand the 10-km zone around the nuclear plants — the province determines the radius of the primary zone — noting that Switzerland is distributing KI pills to everyone within 50 km of a nuclear plant, about four million people in all.
"An evidence-based public review of nuclear emergency plans is desperately needed, and is especially important when determining the radius of the primary zone and the distribution of KI pills," said Schreiner.
"People keep talking about the price we pay for wind energy, but the price we're paying for nuclear doesn't reflect the true cost of the liabilities associated with it."
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