Demystifying Nuclear Waste
Storage, Recycling, and the Future of Clean Energy
Introduction
When people talk about nuclear energy, the conversation often turns to nuclear waste. What is it? Is it dangerous? What do we do with it? These are important questions. Understanding how we manage used nuclear fuel is key to appreciating the safety and sustainability of modern nuclear power.
Let's break down the facts about nuclear waste and explain how small modular reactor (SMR) power plants are designed for responsible and secure management from day one.
What is Nuclear Waste?
Nuclear waste is a broad term, but it generally refers to any material that has become radioactive from being used at a nuclear power plant. It is categorized based on its level of radioactivity.
Low-Level and Intermediate-Level Waste
Most of the waste produced by a nuclear plant, by volume, is low-level waste (LLW). This includes items like protective clothing, tools, and filters that have come into contact with small amounts of radioactive particles. Intermediate-level waste (ILW) is more radioactive and includes things like used reactor components and resins from water purification systems. These materials are handled with established, safe procedures and stored securely.
High-Level Waste: Used Nuclear Fuel
The type of waste that gets the most attention is high-level waste (HLW), which is primarily used nuclear fuel. This is the fuel that has been in a reactor for several years to produce electricity. While it can no longer sustain an efficient chain reaction, it remains thermally hot and highly radioactive.
However, a key fact is often missed: used nuclear fuel is over 95% recyclable. It still contains a vast amount of energy that could be harnessed by existing and advanced nuclear reactors. Today, we treat it as waste, but it could be a valuable energy resource for future generations.
How is Used Nuclear Fuel Managed Today?
The nuclear industry is unique among large-scale power producers in that it contains and manages of all its fuel byproducts. The volume of waste is small. All used fuel produced by the U.S. industry over 60 years would fit on a single football field at a depth of less than 10 yards. Unlike fossil fuel industries, which traditionally vent carbon dioxide and other gases into the atmosphere, the nuclear industry is required by law to monitor, store, and ultimately dispose of all its waste.
For decades, the nuclear industry has used a proven, multi-step process for safely managing used fuel. This approach is globally recognized for its safety and security.
Step 1: Cooling Pools
Immediately after being removed from a reactor, used fuel assemblies are moved to a spent fuel pool. This is a large, deep pool of water located within a reinforced, secure building at the plant site. The water serves two critical functions: it cools the fuel assemblies, which continue to generate heat, and it acts as an effective shield against radiation. Fuel typically remains in these pools for several years.
Step 2: Dry Cask Storage
After its initial cooling period, the fuel is ready for the next stage: dry cask storage. The assemblies are transferred into massive, rugged containers made of steel and concrete. These casks are designed to withstand extreme events, including earthquakes, floods, and impacts.
Once sealed, the casks are passively air-cooled and stored on a concrete pad within the protected area of the power plant. This method is safe, secure, and requires no active cooling systems or electricity. It is a proven, long-term interim storage solution used at nuclear plants around the world.
The Future of Used Fuel: Permanent Disposal and Recycling
The global scientific consensus is that the permanent solution for used fuel is a deep geological repository. This involves placing the used fuel in an engineered facility deep underground in a stable rock formation. Countries like Finland and Sweden are already building these repositories. In the United States, a permanent site has not yet been established, making secure on-site storage at power plants the current strategy. The U.S. Department of Energy (DOE) has responsibility for the final disposal of used fuel under the Nuclear Waste Policy Act.
Another path forward is recycling. Countries like France and Japan already reprocess their used fuel to extract valuable uranium and plutonium, which can be fabricated into new fuel. This process dramatically reduces the volume and long-term radioactivity of the final waste that requires disposal. While the U.S. does not currently recycle used fuel, NuScale’s SMR technology is compatible with advanced fuels, keeping this sustainable option open for the future.
Waste Management at a NuScale SMR-Powered Plant
NuScale’s standard plant design includes comprehensive waste management built directly into the plant’s lifecycle. We use the same proven methods that have been safely employed by the nuclear industry for over 60 years, but with the enhanced safety and efficiency inherent in our SMR design.
Safe and Secure by Design
At a NuScale SMR-powered plant, all used fuel is handled within the Reactor Building, an incredibly robust structure designed to withstand earthquakes and aircraft impacts. The used fuel is stored in a below-grade, stainless steel-lined pool. This provides an additional layer of protection against all external hazards.
After the initial cooling period, the fuel is transferred to industry-standard dry casks for secure on-site storage. We’ve done the math: for a typical 12-module plant, all the used fuel generated over its 60-year life can be safely stored in just 89 dry casks. This entire inventory would fit on a concrete pad of less than one acre.
A Compact and Manageable Footprint
The amount of waste generated by an SMR plant is comparable to that of traditional large-scale reactors per unit of energy produced. Importantly, our technology does not create any new or unique waste streams. We rely on the same conventional uranium fuel and proven management techniques that support the existing nuclear fleet.
By designing our plants to safely store all their used fuel on-site for their entire operational life, we provide a complete solution that is not dependent on the immediate availability of a permanent repository. This gives communities and policymakers certainty and peace of mind.
A Responsible Path Forward for Clean Energy
Responsible waste management is a cornerstone of sustainable nuclear energy. The methods used are not new or experimental. They are proven, regulated, and safe. At NuScale, we have integrated these strategies into our advanced SMR design, ensuring that the clean energy we produce comes with a clear and secure plan for its byproducts.
By embracing this technology, we can provide reliable, carbon-free power to the world while managing its waste responsibly and paving the way for a cleaner and more secure energy future.
