There have been several articles recently about cleaning up nuclear waste, including Plan developed to clean up highly radioactive Hanford spill. First lets distinguish waste from nuclear power plants from waste from wartime production of atomic weapons. Most of what is at Hanford is not the same as what is generated in a nuclear power plant. Hanford is a mess, and will take much more complex steps to clean up, than any nuclear power plant except Fukushima.

(And Fukushima problems were caused by stupid management having the backup power supply for the cooling systems in the flood zone; by not having a sea wall; by having ground water not diverted around the plant, like you’d do for any apartment building, but instead adding pumps to remove water from the basement; by not having an easy way to manually open the vents when the loss of coolant accident led to buildup of hydrogen, so hydrogen exploded — all easily prevented, so no other LWR is likely to ever have those problems.)

We know how to have 800kg waste instead of 250,000kg nuclear waste, to produce the same gigawatt of electricity for a year (1 gigawatt-year electricity), and that 800kg would be short-term radioactive materials. Perhaps it’s time, as we have more and more nuclear waste to store, and as our reactors are getting so old they have to be rebuilt, for us to switch to a much cleaner and safer and less expensive type of nuclear power reactor.

For the conventional (solid fueled) nuclear reactors we’ve been using, a Light Water Reactor, we start with 250,000 kg natural uranium, enrich a rare isotope to make 35,000kg enriched uranium, put it into fuel pellets, and then the reactor only fissions about 1% of that uranium before the fuel rod has to be replaced. 250,000kg to make one gigawatt-year of electricity.

Radioactive cesium and strontium (mentioned in the Hanford article) are two of the fission byproducts from the reactor. The article doesn’t mention the uranium waste, by far the largest part of LWR waste, which a different design of reactor could fission, instead of leaving as “waste”.

A Molten Salt Reactor (such as Liquid Fluoride Thorium Reactor) would use 800 kg of fuel (any isotope of uranium or plutonium from nuclear weapons, fast-spectrum MSR can fission LWR waste, or LFTR can convert thorium to uranium inside the reactor), circulates the molten fuel for 99%+ fissioning, generating a giga-watt-year electricity, and produce very low amounts of waste: 83% of 800kg completely safe in 10 years; remaining 135 kg (300 lbs) completely safe radiation levels in 350 years and nothing to store longer than that.

Compare storing 135kg for 350 years to our current PWR or LWR: storing 250,000kg for thousands to millions of years. And that 135kg could be from 800kg of nuclear waste from LWR.

I’m not talking about store nuclear waste for a while and move it to another nuclear waste storage facility (which is what all the news is about). I’m talking about fission all the fuel, that we took from nuclear waste from weapons or LWR, make electricity from it, and the uranium is gone, the plutonium is gone (fissioned completely) and in 10 to 350 years (depending on the fission byproduct) all that is left are non-radioactive chemicals that are useful for industry.

In addition to delivering carbon-free electricity, LFTRs high-temperature output can generate CO₂-neutral vehicle fuels, using only water and carbon dioxide (from the atmosphere or large CO₂ sources such as coal plants).

The total cost of developing LFTR technology, all certifying of materials and systems, and building assembly line production (like assembly line production of aircraft, with strict safety standards) will be much less than the US$10-$12 Billion for a single new solid-fueled water-cooled reactor or single nuclear waste disposal plant. With sufficient R&D funding (probably less than US$2 billion), five years to commercialization is entirely realistic, and another five years for a national roll-out is very feasible.

This site covers design, safety, nuclear waste, economics, development and testing to be done, proliferation, how LFTRs would fare in accidents or attacks.

We have improved designs of Molten Salt Reactors, but even if we just use the original design that was operational in the 1960s, we would have a much smaller nuclear waste problem. The improved designs would be easier to manufacture, easier to install, with modern quality control, modern sensors, better instrumentation, modern communications and monitoring, and modern security, plus better chemical separation and storage of the fission products.

With the inherent safety of MSR, there is no need for the expensive equipment and expensive manual construction of LWR; Molten Salt Reactors will be much less expensive than LWR with far lower risk. That includes lower risk of “stupid management” errors, and much lower consequence of those errors; MSR won’t have a “Fukushima” — because of physics not because of management.