Although thorium is not today mined in the USA commercially, the US House of Representatives had placed before it on March 16 of this year, last week, a bill sponsored by Mr Joe Sestak (D-Pa) directing the US Navy to study all aspects of utilizing thorium in reactor fuel for shipboard propulsion. Rear Admiral Sestak (Ret) is the highest-ranking former military officer currently serving in the House of Representatives. Last month Senators Hatch and Reid introduced into the Senate, a bipartisan bill to amend the Atomic Energy Act of 1954 to authorize the Nuclear Regulatory Commission (NRC) to study thorium fuel configurations, and to fund such studies. There is certainly a lot of activity in this session of Congress with regard to a metal, which although the US has in abundance, is not mined here at all.
At the very beginning of the nuclear age it was well known that there were two naturally occurring elements which could be utilized to construct nuclear (controlled fission) reactors, uranium and thorium.
The first use for such reactors however was to breed plutonium, which it had been determined was the more practical of the two best studied known fission weapon explosives, uranium 235, and plutonium-239.
The United States alone had by 1960 constructed nearly 20,000 plutonium based nuclear weapons, and it wanted to conserve its supplies of uranium, as did the Soviet Union. Both countries however believed that global dependence on oil imported from politically unstable or immature states could not be relied upon as a safe source of electricity for civilian consumption. Both nations therefore were interested in looking at thorium as a fuel base for civilian reactors to be used solely to produce electricity.
Between 1960 and 1980. the USA constructed or revamped several reactors to test thorium-based fuel configurations. The Soviet Union is believed to have done the same thing. Both nations had the idea that thorium reactors could be, among other things, given to less developed nations so that those nations could not use such reactors to construct nuclear weapons, yet could be made politically and economically dependent on their benefactors both for reactor technology and maintenance and for the fuel and its disposal.
However, by the mid-1970s, it was obvious that politically, the expansion of nuclear power for civilian use was doomed due to the strong opposition of environmental as well as antinuclear activists, none of whom were interested in the facts about reliance on foreign oil or the reduction of the emissions from fossil fuel plants.
It was well known in the world nuclear industry by 1975, that thorium-based fuel could be utilized to dramatically reduce the waste volume from nuclear plants and that such reactors could be seeded with plutonium-239 from dismantled weapons, which in the operation of the reactor, would be rendered difficult or impossible to be utilized for further weapons construction. Nonetheless the development of such reactors under government funding and sponsorship ended in the early 1980s. In the USA, no nuclear reactor fuel can be used without being certified first by the NRC and no further funding was available to do so, so commercial development of such fuels was effectively terminated.
It seems that now, a generation later, with the world literally awash in plutonium from decommissioned weapons – there may be as much as 1000 metric tons of bomb grade plutonium just from decommissioned weapons – and with a growing belief that the supply of oil cannot keep up with the demand and that carbon dioxide emissions from burning fossil fuels are reaching critical levels affecting the world’s climate, it might be a good time to revisit thorium as a non-proliferative (plutonium burning), low waste production, seemingly-abundant nuclear reactor fuel.
The U.S. Congress certainly is almost on top of this one. Funding the NRC to test fuel designs, and authorizing the Navy to compare and contrast thorium reactors with the uranium/plutonium reactors currently in use, is an excellent way to get the job done. I commend the Congress for these actions.
One caveat, however; there is not today, nor has there probably ever been, a primary thorium mine. Thorium has been and is being recovered, in small amounts, as a byproduct from rare earth mining and from uranium mining.
It looks like there is a very large deposit of thorium in the Lemhi Pass region of Idaho and Montana. This deposit must be developed now, because if we are second time lucky with thorium reactors in the USA, and we have developed the deposits in Idaho and Montana, then the US will be self-sufficient in the production of electricity that does not require burning fossil fuel, and does not produce greenhouse gas emissions at all.
If the Lemhi Pass deposits are, in fact, as large as they seem, America can develop a new industry that sells thorium for reactor fuel to nations that have already shown an interest in such developments including India, Norway, China, Russia and even Canada. It looks to me as if it may be cheaper to produce thorium here in the USA, than it will be to do the same in India or China, which have large but diffuse deposits of thorium, contained in rare earth and heavy mineral “sands.”
And, last but not least, the US Navy will be able to build, use, and fuel reactors from resources entirely within the confines of and under the control of the United States of America. What a great idea!