The United States currently stores an immense volume of nuclear waste – around 90,000 tons – across more than 100 temporary sites in 39 states. This presents a complex, decades-long challenge with no permanent solution yet in sight, even as interest in nuclear energy grows. Understanding where this waste is kept and how it’s managed is crucial to grasping this ongoing national issue.
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Key Takeaways:
- The US has two main types of highly radioactive waste: from weapons production and from power generation.
- Each type is stored differently, from underground tanks to above-ground concrete casks.
- Temporary storage locations face challenges, including the threat of corrosion, especially near coastlines.
- A permanent disposal site for nuclear waste remains elusive due to geological and political hurdles.
A Legacy of Atomic Energy
For decades, the US has grappled with finding a long-term home for its accumulating radioactive waste. A federal law in 1987 designated Yucca Mountain in Nevada as the intended permanent site, but political and legal battles stalled construction, and funding was eventually cut in 2011.
Meanwhile, the nation’s 94 operating nuclear reactors continue to produce more waste. Renewed interest in nuclear power, driven by concerns over climate change and the potential for small reactors to power industries like data centers and manufacturing, adds urgency to the search for safe storage solutions. While the Supreme Court recently considered issues related to temporary storage, the quest for a permanent solution is expected to continue for many years.
As a scholar specializing in corrosion and its impact on nuclear waste containment, I’ve studied how this material is stored both temporarily and for eventual disposal. The waste comes primarily in two forms: leftover material from Cold War weapons production and spent fuel from commercial nuclear power plants. There are also smaller quantities from other sources, like medical treatments.
Two Types of Atomic Aftermath
Waste from Weapons Production
The remnants from chemically processing radioactive materials for nuclear weapons, often called “defense waste,” are planned to be mixed with glass in a process called vitrification, then poured into large stainless steel containers. These canisters stand about 10 feet tall, are 2 feet in diameter, and weigh around 5,000 pounds when filled.
Currently, most of this waste is held in underground steel tanks, largely at key former weapons sites like Hanford, Washington, and Savannah River, South Carolina. Although some waste at Savannah River has undergone the glass-making process, much remains in liquid form.
Unfortunately, some radioactive waste has already leaked into the soil beneath tanks at both sites, though officials maintain there’s no immediate public health risk. Ongoing efforts focus on protecting the tanks from corrosion and cracking to prevent further leaks.
What If You Fell Into a Spent Nuclear Fuel Pool? – YouTube thumbnail showing a pool of water with glowing objects
You can learn more about spent fuel pools in this video.
Waste from Generating Electricity
The vast majority of US nuclear waste comes from commercial power plants. This waste starts as bundles of uranium oxide pellets sealed in zirconium tubes, like high-tech fuel logs, about 12 to 16 feet long. Inside a reactor, these “fuel rods” undergo fission – atoms splitting apart – which generates heat, much like a miniature, incredibly powerful heat source. This heat turns water into steam to generate electricity.
After about three to five years, the fission reactions slow down significantly, though the bundles remain intensely radioactive and hot. They are removed from the reactor and placed in a deep pool of water on the power plant grounds. Imagine a massive, heavily shielded swimming pool designed to cool these hot, radioactive bundles safely for about five years.
Once cooled, the bundles are dried and sealed inside welded stainless steel canisters. These canisters are still hot and radioactive, so they are moved to outdoor concrete vaults, essentially sturdy bunkers sitting on concrete pads, also at the power plant site. These vaults have vents to allow air to flow through and continue cooling the canisters.
As of late 2024, the US housed over 315,000 bundles of spent fuel rods and over 3,800 dry storage casks in these concrete vaults across current and former power plants. Even plants that have been dismantled still require the waste on their property to be secured and maintained by the former owner.
Dry spent nuclear fuel storage casks sit near the coastline at San Onofre, California, with surfers visible in the background
Temporary dry storage facilities, like this one near the ocean in California, must contend with environmental factors.
The Hidden Threat: Water and Salt
One persistent challenge for these storage methods is corrosion. Because nuclear power plants need large amounts of water for cooling and generating steam, they are always located near water sources. In the US, nine are situated within two miles of the ocean.
This proximity to saltwater poses a unique threat to waste containers. Breaking waves send saltwater particles into the air. When these particles land on metal surfaces, they can cause corrosion, just like you see on cars or structures near the beach.
At coastal nuclear waste sites, this salt spray can settle on the stainless steel canisters. While stainless steel is generally resistant to rust – think of your shiny kitchen pots and pans – certain conditions can cause localized pitting and cracking. Research, including studies funded by the U.S. Department of Energy, has explored the potential dangers of this type of corrosion on storage canisters near the coast. The findings suggest that steel canisters could pit or crack in salty environments. However, a release of radioactivity would require breaching multiple layers of protection – the container, the zirconium rods, and the fuel itself – making it unlikely that this specific type of corrosion alone would cause a leak.
The Long Road Ahead
Finding a permanent solution for nuclear waste is likely years, if not decades, away. A long-term site must not only be geologically stable enough to contain waste for thousands of years but also gain political acceptance from the public. Additionally, significant challenges exist in safely transporting the waste containers from scattered sites across the country by road or rail to wherever a permanent location is eventually established.
While a temporary consolidated storage site might be established depending on legal outcomes, the vast majority of the nation’s nuclear waste will continue to reside where it is now – in temporary storage facilities across the country – for the foreseeable future.
This article is based on research originally published via The Conversation.
