Paul MacKay
The Ottawa Citizen
June 7, 1998

A huge spinoff industry depends on reactor sales, officials say. But suppliers diversified long ago, writes Richard Foot.

The Candu was originally developed during the Second World War as a means of producing plutonium — a key fissile element in atomic bombs — for the U.S. Manhattan Project. The Candu uses natural uranium fuel and a neutron moderator, (which helps stabilize the chain reaction), called heavy water.

After 1945, the U.S. built several military plutonium production reactors, with Canadian technical assistance. They were essentially copies of the NRX reactor built at AECL’s Chalk River site in 1947. The former Soviet Union developed a similar military reactor to supply its nuclear arsenal. Later, Britain, France, China, and Israel built similar reactors for military purposes. All use natural uranium and heavy water, which produce a high amount of plutonium.

The Candu is a scaled-up version of the NRX, with steam generators added to produce electric power. Due to its military origins, it:

– produces highest amount of plutonium per unit of power output of any commercial reactor;

– produces the highest amount of tritium (a toxic gaseous by-product), which is an essential ingredient in hydrogen bombs;

– has a unique “on-line” fuelling system that allows the reactor to be re-fuelled without a shutdown, and uranium fuel to be shunted through the reactor to produce the maximum amount of bomb-grade plutonium.

For these reasons, the Candu represents the highest risk of military misuse, and nuclear weapons proliferation, of all reactors sold commercially on the world market. Plutonium and tritium can be produced quickly and secretly, making the Candu a potential cover for military activities.

For example, Norm Rubin, a nuclear specialist with Energy Probe, said that, when Ontario Hydro had 20 operating Candu reactors, they produced about 2.5 kilograms of tritium annually, which was distilled (for safety and production reasons) at a plant beside the Darlington nuclear station.

“The average U.S. nuclear warhead uses about four grams of tritium,” says Mr. Rubin. “The Candus, which AECL is selling to China, Turkey and South Korea, could produce enough tritium for dozens of bombs per year.”

In May, 1974, India exploded its first atomic bomb, using plutonium produced in a Candu prototype reactor supplied by Atomic Energy of Canada Ltd. After Canada officially cut off nuclear assistance in protest, India built several carbon-copy reactors and used some of them to produce plutonium for its bomb program. Recently, it has been reported that India obtained the tritium for its H-bombs from the Candu copies.

AECL also sold a Candu to Pakistan. Canada officially cut off nuclear assistance to Pakistan when its nuclear weapons program was exposed.

Last month, Pakistan detonated six inaugural nuclear bombs at an underground test site. Neither country has signed the United Nations-sponsored Nuclear Non-Proliferation Treaty, and the Comprehensive Test Ban Treaty.

Since 1974, AECL has sold full-scale Candu reactors to Argentina, Romania, South Korea, and China (a nuclear weapons state). An NRX reactor was sold to Taiwan. At the time of sale, each of the governments were military dictatorships.

A sale of two Candu reactors to Turkey is pending. Canada is also the world’s largest exporter of uranium, which is mined in northern Saskatchewan. The federal and Saskatchewan governments recently approved development of the world’s largest, richest uranium ore bodies near Cigar Lake. Most of Saskatchewan’s uranium is slated for export to other countries.