By Kim Robson
Traditional nuclear power plants rely on highly unstable elements, uranium-235 and plutonium-239, to power a controlled fission reaction. This controlled chain reaction requires constant cooling to remain manageable. Often the coolant that is used is sea water.
Both the 1979 meltdown at Pennsylvania’s Three Mile Island nuclear plant and the 1986 disaster in Ukraine’s Chernobyl plant have done much to destroy the public’s faith in nuclear power. Then, if the 9.0 magnitude earthquake and tsunami in Japan ,March 2011, wasn’t horrific enough by itself, it also destroyed the Fukushima nuclear plant‘s cooling systems, causing three reactor cores to melt and fuel storage pools to overheat.
On August 19, the plant’s operator, Tokyo Electric Power Company (TEPCO), reported that some 300 tons of highly radioactive water had gone missing from a steel tank. TEPCO believes most of it may have seeped underground but that some might have escaped into the sea. This water had been used to cool the plant’s three melted reactor cores, and the leak has triggered concerns of more leaks from other tanks. The hastily built tanks and foundations, approximately 1,000 in number, are holding 330,000 tons of contaminated radioactive wastewater, which is increasing by 400 tons daily.
The radiation may be running out of control. Recent readings of 1,800 millisieverts per hour were reported – that’s 18 times the level found at the same location 10 days prior. That’s enough gamma radiation to kill an exposed human within four hours.
Experts say that radioactive water leaking through underground utility tunnels connected to reactors and turbine buildings has been finding its way into the oceans for some time. These revelations have heightened concerns about TEPCO’s ability to manage the contamination. The latest controversial plan is to build an ice barrier to block leakage from reaching the ocean, a barrier which will have to be maintained for 200-300 years.
Although nuclear power in the U.S. is on the decline partially from new wind and solar plants, it’s primarily because of new technologies. Hydraulic fracturing, or “fracking,” extracts natural gas and shale oil, both non-renewable fuels whose consumption pumps more greenhouse gasses into the atmosphere. Fracking has been criticized increasingly for its shocking environmental and health consequences.
Surely modern physicists must be able to create better, safer nuclear energy. When the U.S. first started exploring nuclear energy after WWII, scientists experimented with a number of elements. Thorium is perfect for safe nuclear energy because it carries zero risk of meltdown. It cannot sustain a nuclear chain reaction without priming, so fission stops by default in an accelerator-driven reactor. Thorium forms the energy policy backbone of India, where there are abundant supplies. Four times more common than uranium or plutonium Thorium is, in fact, as common as lead.
So the next logical question is why aren’t we using thorium? In the U.S., uranium and plutonium won out as the standards because the byproducts can be used to create nuclear weapons. That’s right. In order to build enough nuclear bombs to destroy the earth 1,000 times, we opted to use highly unstable elements that require constant cooling in order to manage them. If anything goes wrong with that cooling (like an earthquake or tsunami), the result is a meltdown, just as it was at Fukushima. Thorium, on the other hand, can’t be weaponized.
Oak Ridge National Laboratory director Alvin Weinberg lost his job because he dared to champion the safer thorium reactors. Weinberg himself recalls that “[Congressman] Chet Holifield was clearly exasperated with me, and he finally blurted out, ‘Alvin, if you are concerned about the safety of reactors, then I think it may be time for you to leave nuclear energy.’ I was speechless. But it was apparent to me that my style, my attitude, and my perception of the future were no longer in tune with the powers within the AEC.”
Weinberg’s refusal to sacrifice the possibility of safe nuclear power in favor of military weaponization forced him to retire. He knew that thorium could be used in an entirely new kind of reactor, one that would carry zero risk of meltdown. His team built a working reactor, and he spent the rest of his 18-year career trying to make thorium the heart of the nation’s atomic power. Unfortunately, he failed. Uranium reactors already had been established, and Hyman Rickover, of the U.S. nuclear program, wanted the plutonium from uranium-powered nuclear plants to make bombs. Increasingly shut out and pushed aside, Weinberg was finally forced out in 1973.
Weapons-grade fissionable material (233U, transmuted from thorium) is very difficult to retrieve safely or clandestinely from a thorium reactor. Thorium also produces 10 to 10,000 times less long-lived radioactive waste. Radioactive waste from traditional nuclear plants has a half-life of 24,000 years for 239Pu, and an unimaginable 703.8 million years for 235U. Thorium, however, is less radioactive than naturally occurring uranium ore after only a few hundred years.
The good news is that thorium-based reactors are being proposed or are currently in use in a number of countries: the U.S., U.K., Germany, Brazil, India, China, France, Czech Republic, Japan, Russia, Canada, Israel and the Netherlands. A new thorium reactor, unlike petroleum products, could provide energy for 1,000+ years.
Few people have even heard of thorium energy and that it’s a real possibility for long-term, clean, safe atomic energy for the future, with no possibility of catastrophic accidents like those of Hiroshima or Fukushima.