Why Nuclear Waste Is Not Actually Waste

A drawing of a nuclear power plant.

For many people, the first image that pops into mind when they hear “nuclear energy” isn’t a glowing city powered by reliable, clean energy. Instead, it’s the Chernobyl Disaster. The dead trees, ghost towns, and mutated animals that resulted from nuclear waste scare people enough to never even consider nuclear energy as a possible solution to global warming.

However, here’s the thing: the science of nuclear power isn’t all doom, as how we use it has evolved a lot. Behind the newspaper headlines lies one of the most powerful and efficient, yet misunderstood, energy technologies. Though a lot of long-lasting nuclear waste is created when we produce nuclear energy, we’ve developed processes to recycle it, where it’s broken down to extract useful materials. This has long been a solution for the nuclear waste issue.

The science behind nuclear waste and recycling it is fascinating. When a uranium fuel rod is used in a nuclear reactor, only a small fraction of the uranium actually undergoes fission to produce nuclear reactions and, eventually, energy. The rest of the rod either remains as unspent uranium or absorbs neutrons and turns into new, heavier elements called transuranics, which include plutonium (Pu), neptunium (Np), and americium (Am). These elements are highly radioactive and can remain pernicious for thousands of years, thus creating a huge waste issue. 

Nuclear waste recycling was created to target this exact issue. It seeks to recover any valuable materials from the waste instead of simply burying all of it. The key is to separate the reusable components—mainly uranium and plutonium—from the truly unusable parts. This chemical separation is accomplished through a chemical reprocessing method known as Plutonium Uranium Redox Extraction (PUREX). 

The PUREX process is the most widely used reprocessing method today, and the first step is dissolution. This is when spent uranium fuel rods are chopped into small pieces and dissolved in boiling nitric acid, which creates a highly radioactive liquid solution. Second, it’s time for extraction. Using an organic solvent, uranium and plutonium (the useful parts) are chemically separated from the remaining fission products through a series of redox (reduction-oxidation) reactions. Then, the separated uranium and plutonium are converted into new fuel materials for scientists to use. Uranium can be reenriched for new fuel, while plutonium can be blended with uranium oxide to make MOX fuel, which stands for “mixed oxide” fuel. Lastly, the remaining useless fission products are incorporated into stable glass logs to be kept for long-term storage.

A diagram showing how the PUREX method works.

The PUREX process is relatively simple and efficient, yet it is still controversial for its isolation of pure plutonium, which could be used in nuclear weapons. Therefore, many modern reprocessing centers aim to avoid producing pure plutonium by keeping it mixed with other actinides and fission products. 

Of course, scientists are exploring next-generation recycling methods that are safer and more efficient. For example, pyroprocessing, which is a promising alternative method, uses electrochemical separation in molten salts rather than liquid solvents. Pyroprocessing operates at high temperatures and in an inert atmosphere, which minimizes any liquid waste. In addition, it can recycle fuel from more advanced reactors. 

The advantages of recycling nuclear waste are numerous. First, natural uranium is finite, and only about 0.7% of it is the fissile isotope uranium-235 (used for nuclear energy). Thus, the remaining 99.3% isn’t as useful when it comes to producing energy. Recycling allows the recovery of plutonium to act as fuel, which can extend the use of uranium by up to 70%. 

Furthermore, fast reactors can go even further by converting non-fissile Uranium isotopes (primarily Uranium 238) into fissile ones like Uranium 235. Through a process known as breeding, this would make nuclear energy sustainable and reliable for centuries. 

Second, recycling nuclear fuel reduces the need for fresh uranium mining, which is dangerous, exploitative, and environmentally damaging. Because a lot of the nuclear waste is being recycled to be reused, it lessens the need for new geological disposal sites, which are both hard to establish and difficult to maintain. In addition, the reprocessed fuel (MOX) can help countries sustain low-carbon energy production while reducing reliance on fossil fuels, which is beneficial for the fight against climate change. 

Lastly, recycling nuclear waste allows for the reduction of waste volume. Only 3-5% of the spent fuel is truly unrecoverable waste. By recycling the rest, the volume of high-level radioactive waste that actually needs long-term, reliable storage is drastically reduced by almost 80-90%. Furthermore, the remaining waste has fewer long-lived isotopes. This means that the length it takes for the radioactive waste to decay to safe levels takes hundreds of years, rather than tens of thousands of years. 

However, despite the benefits that nuclear waste recycling promises, it still faces scientific, technical, and moral challenges. One of the main challenges of nuclear waste recycling and reprocessing is its cost. Reprocessing facilities are extremely expensive to build and operate. For example, because they require advanced radiation shielding, robotics, and chemical handling systems, France’s La Hague facility, one of the world’s largest reprocessing centers, annually requires billions of dollars to maintain. 

Another problem of nuclear waste reprocessing is the nuclear warfare risks it creates. The PUREX process separates weapon-usable plutonium, which could be used to facilitate the creation of nuclear weapons. Even small quantities could be enough to blow up entire cities. This concern isn’t theoretical, given that several nations have already used reprocessed plutonium to develop nuclear weapon programs. Although newer methods like pyroprocessing mitigate this risk, it cannot be eliminated. Thus, if put into the wrong hands, nuclear waste recycling can threaten global security. 

Despite its risks, however, the effort to recycle nuclear waste reflects the ingenuity of modern science. Nuclear reprocessing and recycling is turning one of humanity’s most daunting problems into something sustainable and reliable by creating a system that can power the world using its own waste. 

But those benefits come with heavy challenges. As mentioned before, the infrastructure required is expensive to construct and maintain, and the risks, especially those involving safety and possible nuclear destruction, are quite concerning. 

In the end, if handled carefully and ethically, nuclear waste recycling could redefine what nuclear energy means, becoming the cornerstone of a cleaner and more sustainable future for the world.