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Uranium Mining: Interview with Dr. Gordon Edwards. Part 3

Anne: Danish authorities say that they will prevent the uranium from Kvanefjeld to be used in nuclear weapons. Is this possible according to you?


Gordon Edwards:


There are at least four different ways in which Greenland’s uranium can end up in nuclear weapons, as discussed below. Can the Danish Government successfully block all these avenues?


In my opinion, it is certainly possible that uranium from Greenland will not be used in nuclear weapons, but Danish authorities do not have the power to guarantee it.

Without uranium there would be no nuclear weapons at all, because a nuclear weapon requires a primary nuclear explosive. And there are only two choices: highly enriched uranium or plutonium. Plutonium is a uranium derivative not found in nature; it is a new element created from uranium inside a nuclear reactor.

The Hiroshima Bomb was made from highly enriched uranium. The Nagasaki Bomb was made from plutonium, which in turn was made from uranium. In every
 case, it starts with uranium.

Here is an outline of four pathways from uranium to the Bomb.


1). Plutonium for Bombs


When uranium from Greenland is used to fuel a nuclear reactor somewhere in the world, about one percent of the uranium fuel is transformed into plutonium. Each nuclear power plant creates enough plutonium, over its lifetime, to make hundreds of nuclear bombs. Once created, plutonium cannot be uncreated, nor can it be rendered unusable as a nuclear explosive. It is virtually indestructible. It lasts for hundreds of thousands of years – far longer than human civilization has existed.


How can the Danish government act to prevent that plutonium from being used in nuclear weapons by some future regime? Thousands of years after a reactor is shut down, dismantled, and forgotten, the plutonium it created will still be there in the irradiated nuclear fuel. Plutonium, made from Greenland’s uranium, will remain ready to be extracted and used for nuclear weapons at any time in the future by any determined government agency or terrorist organization.

2). Highly Enriched Uranium for Bombs


Whoever buys Greenland’s uranium will need to have the uranium enriched before it can be used as reactor fuel. Uranium enrichment is a very sensitive technology because it can be used to make explosive material for nuclear Bombs. 
This requires some explanation.

Uranium found in nature is always a blend of two types, called uranium-235 and uranium-238. As the numbers suggest, U-238 atoms are a bit heavier than U-235 atoms. It was discovered long ago (1939) that U-238 cannot be used as a nuclear explosive whereas U-235 can. The lighter variety of uranium is the explosive one.


But the amount of U-235 in “natural uranium” (found in nature) is much too small to allow for a nuclear explosion. To be precise, 0.7 percent of the mass is U-235 and the rest is U-238; so U-235 is less than three-quarters of one percent of the total.


For a nuclear explosion, you need more than 20 percent U-235. Such material is called “highly enriched uranium” (HEU). Uranium that is over 90 percent U-235 is called “weapons-grade uranium”, but any form of HEU (over 20 percent) is usable as a nuclear explosive and has to be subject to the strictest kind of military security.


Uranium enrichment is a procedure designed to increase the concentration of U-235 by slowly and painstakingly removing and discarding a great deal of U-238. The end product is “enriched uranium”; it has a higher concentration of U-235 than natural uranium does. Meanwhile, the large volume of discarded uranium is called “depleted uranium”. It is mainly U-238, and is considered radioactive waste.


As events in Iran have shown, the very existence of a uranium enrichment facility poses a potential military threat because no outsider can be sure what is going on inside. How can the Danish government be certain that weapons-grade uranium is not being produced without its knowledge? Accounting may eventually reveal criminal misuse after the fact, but it is unable to prevent such misuse in advance. Extraordinary control is needed to ensure that no HEU is produced at any time.


If HEU is produced, even for civilian purposes, that material can easily be diverted for use in nuclear weapons by any rogue government or subnational group that manages to access the stuff. Making an A-Bomb from HEU is foolproof; like the Hiroshima Bomb, such a nuclear explosive device needs no testing before use.


Does the Danish government have procedures to police all of this activity? Or will that task be out-sourced to another agency in hopes that it will do the job?

3). Depleted Uranium for Plutonium Production


Nuclear power reactors generally require 3 to 4 percent U-235 in order to function. That material is called “low enriched uranium” (LEU). You cannot make a nuclear explosive from low enriched uranium directly. Such uranium is not weapons-usable. However, it is energetic enough to fuel a nuclear reactor and generate electricity.


Plutonium is different. Any type of reactor-produced plutonium can be used as a nuclear explosive. And when uranium is used as fuel in a nuclear reactor, some of it is turned into plutonium, so in this way, even LEU is transformed into a nuclear weapons-usable material – as outlined in point 1) above.


But there’s another, more devious way that LEU leads to plutonium for Bombs. It involves depleted uranium.


To obtain one kilogram of reactor fuel, you need to start with a bit more than 8 kilograms of natural uranium. During the enrichment process, more than 7 kilograms are discarded as “depleted uranium”. Thus 85 to 90 percent of all uranium mined in Greenland will end up as cast-off depleted uranium.

Depleted uranium is regarded as a waste, so it is not very carefully controlled or inspected or safeguarded. It is freely used by the military for a variety of purposes. One of those purposes is to mass-produce plutonium for nuclear weapons. This is done by inserting “target rods” made of depleted uranium into a specialized military reactor. When the U-238 targets are irradiated, some of the uranium atoms are transformed into plutonium atoms. Voilà. Plutonium for warheads.


The only way to prevent such military usage
 of depleted uranium would be to require that all of the depleted uranium be returned to Denmark or to Greenland. Is the Danish government prepared to do that?

4). Depleted uranium used in Nuclear Warheads


Virtually all nuclear weapons currently deployed by the five main nuclear weapons states – USA, Russia, China, France and Britain – are three-stage thermonuclear weapons, often described as “fission-fusion-fission” weapons. These devices are typically tens to hundreds of times more powerful than the earliest A-Bombs.


Nuclear warheads use plutonium as the primary nuclear explosive material. Often called a “trigger”, the primary explosion (the first stage) can be thought of as a smaller version of the Nagaski bomb. When the trigger is detonated it instantly raises the temperature to 50 million degrees and ignites the secondary explosion (the second stage), which is an uncontrolled nuclear fusion reaction, giving off an enormous burst of extremely energetic neutrons.


The third stage of the explosion is caused when those powerful fusion neutrons bombard the surrounding components of the thermonuclear weapon, made from depleted uranium metal. The neutrons force the U-238 atoms to fission, thereby more than doubling the destructive blast of the explosion and causing most of the radioactive fallout material that is swept up by the fireball into the mushroom cloud.


Is the Danish government aware that over half of the total destructive power in the world’s nuclear arsenals is due to the depleted uranium in the warheads? How does the government plan to prevent the depleted uranium from Greenland from being used in this way? According to Greenland Mining and Energy, GME, there are about 269 thousand tonnes of natural uranium in the Kvanefjeld deposit, so there would be about 235 thousand tonnes of depleted uranium left over from the enrichment of LEU fuel. Will Denmark repatriate this radioactive waste material to keep it out of circulation?


Conclusion


I do not believe that the Danish government, or any other government, or any international agency, can guarantee that the plutonium produced in nuclear reactors will never be used in nuclear weapons, or that the depleted uranium left over from uranium enrichment will never be used to produce plutonium triggers or to construct metallic components for nuclear warheads.

As Albert Einstein once said, "The splitting of the atom has changed everything, save man’s mode of thinking. Thus we drift toward unparalleled catastrophe.” A world without nuclear weapons has a chance of surviving. A world bristling with nuclear arsenals has no chance.


To help bring about a world free of nuclear weapons, the International Physicians for the Prevention of Nuclear War (IPPNW) have concluded that uranium mining should be banned. By itself, that is not enough -- but it is a necessary first step.


...........................................

2 other interviews with Dr. Gordon Edwards



Part 1: Uranium Mining: Interview with Dr. Gordon Edwards June 28th 2016

Anne:  Canada is and always has been one of the biggest producers and exporters of uranium in the world. Nevertheless, three of Canada’s ten provinces have outlawed uranium mining, and health professionals have played an important role in each case. Could you please explain why these medical professionals are opposed to uranium mining?
 
Gordon Edwards: This is a great question. The answer hinges on the remarkable properties of uranium, and the unprecedented nature of the health dangers that it poses. In order to answer the question properly, a good deal of explanation is required. For Edwards' complete response see the following link: https://atomposten.blogspot.dk/2016/06/uranium-mining-interview-with-dr-gordon.html


Part 2 Uranium Mining: Interview with Dr. Gordon Edwards July 4th 2016

Anne:  Danish experts Gert Asmund and Violeta Hansen from the Danish Center for Environment and Energy University of Aarhus have mentioned to me that Cluff Lake is a good example of uranium mining remediation. Do you agree?

Gordon Edwards: It is much too early to determine the long-term success or failure of remediation efforts at Cluff Lake. There has already been one spectacular failure at that site, and there may be more to come. For Edwards' complete response see the following link: https://atomposten.blogspot.dk/2016/07/uranium-mining-interview-with-dr-gordon.html

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