What do new nuclear reactors mean for waste?

The world of nuclear energy faces a paradox that is hard to ignore. On one hand, new small and modular reactors (SMR) promise a revolution — clean energy, smaller sizes, greater deployment flexibility. On the other hand, each new reactor is also a new source of radioactive waste that will require safe storage for tens of thousands of years. The question is therefore not "whether new reactors are a good idea," but rather "whether we can finally deal with a problem that has existed for decades?".

The current situation is surprisingly chaotic. The world has no universal solution for radioactive waste — each country is figuring it out on its own. Some countries melt fuel in cooling pools, others place it in steel containers, still others have buried it in deep bunkers. Poland, wanting to enter the era of nuclear energy, will have to face this same uncomfortable reality. New reactors may be technologically advanced, but the infrastructure to handle their waste remains a fundamental problem.

How much atomic waste is really produced?

Before we move on to solutions, it's worth understanding the scale of the problem. A nuclear reactor with a power of 1000 megawatts operating for a year produces approximately 30 tons of spent nuclear fuel. It sounds like a small amount, but here's the catch — this amount of material will be dangerous to health for generations. Currently, over 250,000 tons of spent nuclear fuel have been accumulated worldwide, and this number is growing every year.

It is worth, however, distinguishing between different types of waste. Not everything that comes from a reactor is equally dangerous. There are low-level radioactive waste (such as worn-out workers' suits or filter materials), medium-level and high-level waste. The latter represents a small percentage by volume, but contains most of the radioactivity. Highly radioactive waste is primarily spent nuclear fuel — a complex mixture of uranium, plutonium, and fission products.

New SMR-type reactors could change this balance. Smaller reactors mean smaller amounts of fuel, but the distribution of the number of reactors will be different. Instead of a dozen large nuclear power plants, there could be hundreds of small installations scattered throughout the country. This raises a logistical question: how to transport and store waste from thousands of locations instead of from dozens of centers?

Where to keep what you're afraid to keep?

The history of nuclear waste storage is a history of political indecision. In the United States, for decades plans assumed building a central repository in Yucca Mountain in Nevada. The project cost billions of dollars, but never came to fruition — mainly due to local community opposition and changing political priorities. Today, the United States still has no final solution for its high-level waste.

Sweden, on the other hand, chose a different path and seems to be doing it sensibly. The country is building a repository in deep granite formations, approximately 500 meters below the surface, in a place called Forsmark. The project, known as the Deep Repository, is expected to be ready to accept waste within a few years. The Swedes argue that granite is an ideal rock — chemically stable, impermeable to water, isolated from the surface environment.

France chose a different strategy — fuel recycling. Instead of storing all spent fuel, the French send it to processing plants where they extract plutonium and uranium for reuse. The remaining waste is less voluminous and less active. This solution reduces the problem but does not eliminate it — there is still waste that must be placed somewhere.

Poland will have to choose between these models. Building a central repository is a huge technical and political challenge — you need to find a location that society will accept, invest billions of zlotys, and then maintain the facility for thousands of years. An alternative is to send waste abroad, which has its own ethical and practical problems.

Do new reactors produce less waste?

This is a question that nuclear energy advocates ask themselves when they want to argue in its favor. The answer is — as is often the case in science — complicated. Some new reactor designs can indeed operate with higher fuel efficiency, which theoretically reduces the amount of waste per unit of energy produced. However, the difference is not dramatic.

More interesting is the scenario in which new reactors can operate on fuel recovered from waste. Fast breeder reactors, such as those being developed by companies working on fourth-generation nuclear energy, can burn plutonium and actinides from previously spent fuel. This theoretically reduces the amount of long-lived waste that needs to be stored forever. Instead, waste would be reduced through successive burn cycles.

However, the technology of fast reactors, which can do this, is still experimental. France had the EBR-II reactor, but closed it. Russia has demonstration reactors, but they are reserved mainly for military and research purposes. Therefore, the promised waste reduction through recycling remains primarily a future scenario, not a current reality.

Small reactor, big transportation problem

New modular reactors are to be deployed in many locations — in small towns, at industrial complexes, on mining sites. This means that waste will come from dispersed sources. The transport of radioactive materials is an operation requiring extraordinary safety measures. Vehicles must be specially prepared, routes planned, personnel trained.

Increasing the number of reactors from a dozen to potentially hundreds also means increasing the number of transports. In Poland, a country with dense development and a well-developed communication network, this logistics will be a challenge. Each transport is a potential point of danger — accidents, leaks, incidents. Society, which is already skeptical of nuclear energy, will be even more sensitive to these risks.

Theoretically, one could build small storage facilities near each reactor, but this would be costly and inefficient. A better solution would be a regional processing and storage center, but such facilities are difficult to locate — every community wants the waste to be somewhere else.

Can technology solve what politics cannot?

In recent years, promising research has emerged on methods to reduce the radioactivity of waste. Transmutation — a process in which long-lived isotopes are converted into short-lived ones by neutron bombardment — is theoretically possible. If it succeeded on an industrial scale, it could drastically shorten the time that waste poses a threat, from millions of years to thousands or hundreds of years.

However, transmutation technology remains in the research phase. European research projects, such as MYRRHA in Belgium, are working on transmutation reactors, but these are experimental facilities, not ready-made solutions. Even if the technology succeeds, its implementation on an industrial scale will take decades.

Another promising direction is deep geological storage with monitoring. Instead of assuming that a container will remain sealed forever, new approaches assume active monitoring and the possibility of retrieving waste in the future if better technology emerges. This changes the paradigm from "bury and forget" to "bury and observe".

Poland between pragmatism and ideology

Poland is entering the field of nuclear energy at a time when globally there is a debate about the future of this energy source. On one hand, the country needs decarbonization — it has to achieve the European Union's climate goals. On the other hand, Polish society is traditionally skeptical of nuclear energy, and the waste issue is a central point of this skepticism.

The Polish Atomic Energy Agency and the government must therefore make several difficult decisions. First, will the country store waste domestically or will it export it? Second, will investment in new storage infrastructure be preceded by public education and consultation? Third, will this be temporary or final storage?

Other European countries are already struggling with these questions. Germany, abandoning nuclear energy, must still manage waste from reactors that were in use for decades. France, opting for nuclear energy, must invest in processing and storage infrastructure. Poland has the opportunity to learn from these experiences.

The real picture: waste is already here

It is important to understand that the problem of radioactive waste will not appear only when new reactors start operating. Poland already has small amounts of nuclear waste from scientific and medical research. The Institute of Atomic Energy in Otwock stores radioactive materials. Universities have radioactive sources. These quantities are small compared to what large reactors would generate, but the storage problem already exists.

This means that Poland should already be building infrastructure and experience in waste management. Building a repository or central storage facility should be a process started before the first large reactors are launched, not after. Delay in this area will mean that waste will accumulate in temporary storage facilities, which carries greater risks.

New reactors, whether they will be large atomic units or small modules, will not solve the waste problem — they will only increase it. Technology can help reduce the scale of the problem, but cannot completely eliminate it. Poland, planning its entry into the era of nuclear energy, must therefore accept that waste is not a theoretical future problem, but a present, practical reality that must be solved here and now.