In fact, power reactors are no strangers to plutonium fuel. Plutonium is a natural byproduct of the fission process, created by neutron capture in the uranium-238 nucleus. In a CANDU reactor enough plutonium is created in this manner to provide about half of the total energy produced. Under these circumstances, the plutonium in the fuel is called "reactor-grade", and while being inefficient as a bomb material, is quite suitable as power-reactor fuel (see related FAQ). In this manner, nuclear reactors actually "create" fuel from their own waste products, during routine operation.

The suggestion comes naturally, therefore, that power reactors might be used to process surplus weapons-grade plutonium as well. This strategy formed one half of a two-track approach announced by the U.S. government in December 1996, as its plan for dealing with surplus weapons plutonium (see "Latest News" below for current status). The other strategy was to immobilize the plutonium in a glassified ("vitrified") mixture of spent fuel, and then bury it. This two-track approach was in accordance with the recommendations of the U.S. National Academy of Sciences study, which were subsequently accepted by the U.S. Department of Energy.

This is a prevalent misconception. The issue is a 1974 atomic test explosion by India, which led to an immediate severance of international cooperation in India's nuclear technological development that exists to this day, except for maintenance and operational issues related to safety. Similar sanctions were placed on Pakistan as well. The plutonium used in this explosion was manufactured in a small research reactor near Bombay, India, which Canada supplied as part of a larger "technology-transfer" program in the late 50's, early 60's.

The Indian research reactor, CIRUS, was based on Canada's NRX design, a heavy-water-moderated, light-water-cooled research reactor commissioned in 1947 at AECL Chalk River Laboratories (2 hours west of Ottawa). The main role of the NRX, which was decommissioned in the late 1980's, centred around materials testing, solid-state physics research, and isotope production, although it initially served as a prototype heavy-water plutonium production reactor, conceived during the days of the WWII Manhattan Project under a tripartite agreement between Canada, the U.S., and Britain (see related FAQ, also "Early Years of Nuclear Energy Research in Canada" by Dr. G.C. Laurence, and the author's article, "Entering the Nuclear Age", published in Legion Magazine). Heavy water for the Indian CIRUS reactor was provided by the United States; hence the "US" in the title (the original name for the reactor was simply "CIR", for "Canada-India Reactor"; in Bothwell's 1988 history of AECL, "Nucleus", the name "CIRUS" is also linked to Cyrus, shah of ancient Persia, as well as the name "Canada India Reactor Uranium System").

As an issue affecting CANDU reactors, the matter is irrelevant. The technology for producing electricity with a CANDU reactor is highly incompatible with the production of weapons-grade plutonium (see related FAQ). However, because of the highly technical differences between research reactors and power reactors, along with the regrettable fact that the Indian affair is linked to Canadian technology, the incident has caused some confusion.

India's 'peaceful' bomb
Broadcast Date: May 20, 1974

An uninvited guest has joined the nuclear club, and fingers are pointing at Canada. On May 18, 1974, India detonates a 12-kiloton nuclear explosive in the Rajasthan desert. It was built using plutonium from a research reactor donated by Canada in 1956. The explosion prompts fierce criticism of Canada's nuclear exports, and a wall of excuses from officials in both Canada and India. Canadian officials say they couldn't stop it. India denies it was even a bomb.
India's 'peaceful' bomb

• The nuclear device was built using plutonium obtained from the 40-megawatt Cirus research reactor, a gift from Canada. It was donated under the Commonwealth "Colombo Plan" aid program, which sought to promote economic and social development in South and Southeast Asia.
• The gift helped pave the way for future reactor sales: Canada sold India two Candu reactors (in 1963 and 1966), and India now has a number of Candu clones.

• The Cirus reactor (which was not a Candu) was modeled on the Chalk River NRX reactor. It was donated on the condition that it only be used for peaceful purposes — so India claimed their 1974 explosion was "peaceful" and would help them in industries such as mining.
• India referred to the device as the "Peaceful Nuclear Explosive" or PNE. It was also called "Smiling Buddha."

• The 1974 explosion was criticized around the world, and most nations (including Canada) stopped lending India technical assistance. India soon built a plutonium separation plant to help refine plutonium from its nuclear waste, and developed its own nuclear reactors based on the Cirus design. That gave India a legal source of plutonium with which to make bombs.

• Canada sold a 125-megawatt reactor to Pakistan in 1959 and a Candu in 1964. After India's nuclear test in 1974, Canada wanted Pakistan to promise never to build a bomb using plutonium from Canadian reactors, but Pakistan, which went to war with India in 1965, refused. Pakistani Prime Minister Zulfiqar Ali Bhutto declared that Pakistan would build the bomb "even if we have to eat grass or leaves or to remain hungry."

• The Treaty on the Non-Proliferation of Nuclear Weapons (NPT) was introduced in 1968 and became international law in 1970. It was signed by 187 nations promising to stop the spread of nuclear weapons to nations that did not have them, and to promote disarmament among those that did. At the time only the United States, United Kingdom, USSR, France and China had the bomb. Since then, India, Israel and Pakistan have developed nuclear weapons, and together with Cuba are the only ones to refuse to sign the treaty.


• On May 11 and 13, 1998, India detonated underground nuclear bombs, admitting to the world that it now had the bomb. By the end of the month, Pakistan responded with test blasts of their own.

India's 'peaceful' bomb

Medium: Radio

Program: As It Happens

Broadcast Date: May 20, 1974

Guest(s): Donald G. Hurst, Samar Sen


Host: Harry Brown
Interviewer: Barbara Frum

Duration: 07:49

Last updated:
Oct. 28, 2008

perhaps a deficit was necessary for the CBC, but now I expect them to be just as accountable as CTV.

I remember watching the grey cup about 10 years ago. CTV had commercials like Ford and General Foods. Yet, CBC was doing public announcements.

Why are we subsidizing a network that won't even try to make money from the programs that they are broadcasting?

This is a question that cannot be answered simply. First, however, two related misconceptions must be put to rest:

1. Nuclear fuel (spent or otherwise) inside or outside of a CANDU reactor (or any power reactor) cannot explode like an atomic bomb; and,

2. An atomic bomb has never been manufactured using spent fuel from a CANDU reactor (see the two previous FAQs for more on the misconception that India may have done exactly this).

The next point to be made is that it is not technically impossible, given sufficient ingenuity, expertise, expense, personal health risk, and luck, to make an explosive device from the plutonium present in spent CANDU reactor fuel (or any spent power-reactor fuel). However, since terrorist organizations may indeed meet the preceding criteria, the relevant question, and the subject of this FAQ, is "how easily" could this be accomplished?

The issue of nuclear weapons proliferation, involving any form and purity of fissile material, is an important concern. It is important that we understand it, and neither underestimate nor overestimate the risks. To commit the former invites obvious consequences; to commit the latter can be equally catastrophic: anti-proliferation resources can be diverted to less worthy (i.e. lower risk) targets, and related infrastructures (e.g. civilian nuclear power) can be degraded or disassembled for illegitimate reasons.

Well I consider it a Canadian Icon... I grew up listening to the CBC. I am close to retirement age and remember my dad listening to it on our way back from our Cottage. Through programs like cross country check up and others I learned about our sameness and our diversity. I think it keeps us connected.

This has been an interesting read, but are there any physicists or chemists here who could explain this a little for us? Do we have any science types that explain the differences in various "grades" of plutonium and what's needed to create them?

There are two kinds (isotopes) of uranium: the rare U-235, used in bombs, and the more common, heavier, but useless U-238. Natural uranium contains less than 1 percent U-235 and in order to be usable in bombs it has to be "enriched" to 90 percent U-235 and only 10 percent U-238. Plutonium-239 can also be used in bombs as a substitute for U-235. Ten pounds of U-235 (or slightly less plutonium) is all that is necessary for a bomb. Less than ten pounds won't give you a critical mass. So purifying or enriching naturally occurring uranium is likely to be your first big hurdle. It is infinitely easy to steal ready-to-use enriched uranium or plutonium than to enrich some yourself. And stealing uranium is not as hard as it sounds.