Gordon Edwards on weapons-grade plutonium (and Japan)

Weapons-Grade Nuclear Explosive Materials

The good news is that weapons-grade nuclear materials in many countries are being rounded up and confined to a smaller number of high-security locations in order to at least begin to reduce the risk of criminal organizations or terrorist groups getting their hands on the nuclear explosive materials needed to make a powerful atomic bomb.

The nuclear explosive materials in question are (1) Highly Enriched Uranium or HEU, and (2) Plutonium or Pu.  These are the only two types of materials that can be used to make an atomic bomb at the present time. The Hiroshima bomb used Highly Enriched Uranium as a nuclear explosive, whereas the Nagasaki bomb used plutonium. 

For the would-be bomb-maker, the main advantage of HEU is that it is much easier to make an atomic bomb with it, using a "gun-type" mechanism, compared with plutonium, which requires a more elaborate "implosion-type" mechanism.  The gun-type device is so simple and direct that testing is unnecessary -- it is guaranteed to produce a very powerful atomic explosion.  The implosion-type device is considerably trickier but not beyond the abilities of a well-equipped terrorist organization.

But bomb-makers find plutonium has many advantages too.  (1) Plutonium is a more powerful explosive, so less plutonium than HEU is needed to destroy a city. (2) Plutonium is extracted chemically from irradiated nuclear fuel all at once, unlike HEU which has to be produced by a long slow energy-intensive process of gradual enrichment. (3) Plutonium is used as an explosive "trigger" to set off even more powerful "H-bombs" -- using the nuclear fission to ignite a nuclear fusion reaction. 

When nuclear weapons are dismantled, the plutonium "triggers" are removed.  Without plutonium these warheads are useless; no nuclear explosion is possible.  But the "excess" weapons-grade plutonium has to be carefully guarded forever because we do not know at the present time how to destroy plutonium or eliminate it once it has been created.

Other Nuclear Explosive Materials

The bad news is that weapons-usable nuclear materials are NOT being rounded up and NOT being prohibited internationally.  Weapons-grade materials are not the same as weapons-usable materials. Weapons-usable nuclear materials continue to be produced, and will become increasingly accessible to criminal organizations as time goes on.

Plutonium poses the greatest danger in this regard, because ANY form of reactor-produced plutonium can be used to make a powerful, highly effective and completely reliable nuclear weapon.  One doesn't need to have "weapons-grade" plutonium for this purpose; any plutonium will do.  See http://ccnr.org/plute_sandia.html .

"Weapons-grade" plutonium refers to the highest quality of plutonium, in which the predominant isotope is  plutonium-239 (Pu-239) with relatively little of the other isotopes of plutonium, especially plutonium-240.  On the other hand "reactor-grade" plutonium has up to 40 percent plutonium-240 along with the more abundant plutonium-239.  Given the choice, any bomb-maker would prefer to use weapons-grade plutonium because it is easier to handle and more predictable in outcome (the force of the blast).  However reactor-grade plutonium can be used to make an effective, highly reliable weapon at any level of technical sophistication.  See http://ccnr.org/Findings_plute.html .

Because the nuclear industry wants to be able to use plutonium to replace -- or at least to supplement -- uranium as a fuel for nuclear reactors, their public relations machinery has created a myth that has deceived many decision-makers, even in very high places, as well as most of the people who work in the nuclear industry.  The myth maintains that reactor-grade plutonium is "unsuitable" for nuclear weapons use. Without plutonium as a fuel, any massive expansion of nuclear power is impossible.

But this particular myth -- that reactor-grade plutonium is unsuitable for bombs -- is not at all true.  It would be more correct to say that reactor-grade plutonium is somewhat less convenient than weapons-grade plutonium for nuclear weapons use, but so what?  As Sandia Labs declared in one of their major publications, "For nuclear weapons use, ALL plutonium is GOOD plutonium."  

See http://ccnr.org/plute_sandia.html .

From the point of view of non-proliferation, plutonium poses much greater difficulties in the very long term than HEU does, because HEU can be "denatured" -- made absolutely unusable for nuclear weapons -- whereas plutonium cannot.  

It is impossible to make a bomb with unenriched uranium, because there just isn't enough uranium-235 to make an explosion possible.  In the case of uranium, the most abundant naturally occurring isotope, uranium-238, is NOT a nuclear explosive material at all, so it can be used as a "denaturing" agent to dilute uranium-235 down to harmless proportions.  

There is no counterpart in the case of plutonium.

 ANY kind of plutonium -- even pure plutonium-240 -- can be used as a powerful nuclear explosive.  In fact plutonium-240 is a more powerful nuclear explosive than uranium-235 -- and the same is true for all other plutonium isotopes.  See 

''Explosive Properties of Reactor-Grade Plutonium'' by Carson Mark, excerpted with a hot-link in

http://ccnr.org/Findings_plute.html .

Brave New World

As Pierre Elliott Trudeau told the United Nations General Assembly's Special Session on Disarmament in 1978, if we want to have a world without nuclear weapons, then we have to begin by "suffocating" the nuclear arms race by "choking off the vital oxygen on which it feeds".  He was referring to the production of nuclear explosive materials --  enriched uranium and plutonium.  As long as we continue to produce these materials it will be impossible to eliminate nuclear weapons.  

On the other hand, if we stop the production of these nuclear explosive materials worldwide, then we have a chance to dismantle existing arsenals of nuclear weapons and achieve a nuclear-weapons-free world. That means that uranium enrichment plants everywhere (not just in Iran!) and plutonium reprocessing plants everywhere (not just in North Korea!) will have to be internationally outlawed.  Then weapons-usable uranium can be down-graded to levels that cannot be used for bombs, and that cannot be upgraded without building a uranium enrichment facility first.  Also, existing stockpiles of "separated plutonium" can be re-mixed with the fiercely radioactive liquid wastes contained all the fission products and other nuclear waste materials from the irradiated nuclear fuel, so that the plutonium is no longer accessible without a chemical reprocessing operation. 

Such security measures, while not perfect, requiring constant vigilance, would at least create a situation of sufficient stability to allow for the gradual elimination of all nuclear weapons in the world, if that is determined by world leaders to be the sanest objective for the continued survival of the human race.  

Reality Bites

But that's not what is happening.  Look at Japan for example.  While self-congratulatory articles are being written about the significant quantities of highly enriched uranium and plutonium that are being shipped back to the USA from Japan, there is slight mention of the fact that the Japanese Government plans to give the go-ahead this year for the start-up of their $21 billion reprocessing plant, which will begin extracting weapons-usable plutonium from irradiated nuclear fuel on a mass-production basis.

So the security measures associated with weapons-grade materials run the risk of being merely window-dressing, camouflaging and in no way putting the brakes on industry plans to mass-produce nuclear-weapons-usable materials,  thereby making a nuclear weapons free world politically impossible. 

This kind of decision cannot be regarded as a commercial or economic decision like any other -- it could very well seal the Fate of the Earth. (Jonathan Schell, the author of the profoundly thought-provoking book The Fate of the Earth, passed away in New York City on Tuesday, March 25, 2014.)

It is up to the peoples of the Earth to see the enormity of what is going on and to speak up now and act so as to keep alive the hope for a sustainable future for our great great grandchildren.  A non-nuclear-weapons-future should not be foreclosed by the expediency requirements of the commercial nuclear power industry.

Gordon Edwards.

See PDF version  http://ccnr.org/Plute_Perplex.pdf