Nuclear Waste Dumped in the Ocean 50 Years Ago: Is It Still Safe? Deep-Sea Corrosion and Leakage Confirmed

The expert committee for high-level radioactive waste management held its first meeting, taking the first step towards the ultimate goal of securing a disposal site for spent nuclear fuel. Formed under the High-Level Radioactive Waste Act, this committee is establishing safe management plans for spent nuclear fuel and discussing specific plans for securing long-term disposal facilities. This first meeting is expected to be a significant turning point for resolving the domestic high-level nuclear waste problem.

Committee member Lee Jung-hyun stated, "There is a high-level radioactive waste management committee established under the High-Level Radioactive Waste Act. We held our first meeting today as an expert committee under it," formalizing the committee's launch and initial activities.

This signifies the full-fledged start of building a system for the permanent management of high-level radioactive waste generated domestically.

It was pointed out that the plan to reprocess spent nuclear fuel for reuse and to establish a permanent recycling system through fast reactors essentially failed. This suggests that technical challenges still exist in the disposal of high-level nuclear waste.

Committee member Lee Jung-hyun stated, "The idea was to reprocess spent nuclear fuel for reuse and to create a system that could permanently recycle it through fast reactors. But that essence has failed. Until now.", acknowledging the limitations of reprocessing technology.

It was revealed that over 200,000 drums of nuclear waste were illegally dumped in the deep sea of the Northeast Atlantic at a depth of 4,700m from 1946 to the 1990s. Investigations conducted using the Nautilus submarine, led by the French National Centre for Scientific Research (CNRS), confirmed that the metal containers discarded in the seabed basin were corroded and damaged.

Committee member Lee Jung-hyun explained, "Over 200,000 drums of nuclear waste were dumped in the Northeast Atlantic at a depth of 4,700m. That was from 1946 to the 1990s.", emphasizing the long-term scale of the dumping.

This investigation provided an in-depth analysis of the condition of the nuclear waste, left for a long time, and its impact on the surrounding environment.

In 1972, signatory states of the London Convention added a provision to completely prohibit the dumping of radioactive waste at sea starting in 1993. However, with Japan currently discharging contaminated water from Fukushima into the ocean, controversy over international equity is rising, comparing it to past cases of nuclear waste dumping.

Committee member Lee Jung-hyun pointed out, "The entire world joined that treaty in 1972, and from 1993, a provision was added prohibiting all signatory states from dumping radioactive waste at sea. Japan is doing it now.", criticizing Japan's actions.

This raises fundamental questions about compliance with international environmental regulations and responsibility for nuclear waste management.

A primary survey to pinpoint and map the exact locations of nuclear waste that had been in the sea for over 50 years was conducted in 2025. Subsequently, in 2026, 20 deep-sea dives using the 'Nautilus' submarine located the waste dumped at a depth of 4,700m, collected samples, and completed radionuclide analysis.

A survey official explained, "In the primary survey, we located and mapped the position of this waste, which had been there for over 50 years. Then, this year, using a submarine called Nautilus, we conducted 20 dives to revisit the waste dumped at about 4,700m, took photos, collected samples, and performed radionuclide analysis to identify what kind of radionuclides were present in the nuclear waste.", detailing the survey process.

A survey official explained, "In the primary survey, we located and mapped the position of this waste, which had been there for over 50 years. Then, this year, using a submarine called Nautilus, we conducted 20 dives to revisit the waste dumped at about 4,700m, took photos, collected samples, and performed radionuclide analysis to identify what kind of radionuclides were present in the nuclear waste.", detailing the survey process.

Iron containers dumped in the deep sea of the Northeast Atlantic were found to be severely corroded and deteriorated over 50 years. Corrosion was particularly accelerated in the seawater environment, and in some containers, content exposure was observed, indicating the leakage of radioactive materials into the surrounding seawater.

An official explained, "The iron containers were severely deteriorated and corroded. Because it's seawater, the corrosion is particularly severe. And some contents were exposed, and substances coming out into the surrounding seawater were confirmed. However, it is important to note that not all 200,000 units have leaked. We are still investigating, so it's hard to say that all have leaked. However, the possibility is high."

Although it is difficult to definitively conclude the leakage status of all 200,000 waste containers, it is highly probable that problems have occurred in a significant number of them.

Criticism has been raised that the current nuclear waste problem imposes an enormous burden on future generations, leading to the 'intergenerational responsibility' argument. It is argued that passing on the problem of nuclear waste disposal, which costs tens of trillions of won, to the next generation like a Silla Dynasty artifact from a thousand years ago is morally unacceptable.

One panelist strongly criticized, "If we switch positions, what if we had to spend our money now to retrieve leaked nuclear waste dumped by the Silla Dynasty a thousand years ago, move it elsewhere, and safely dispose of it? And spend tens of trillions to do that. How could we agree to that? We can't even pass on good things, so why leave behind such nuclear waste?"

One panelist strongly criticized, "If we switch positions, what if we had to spend our money now to retrieve leaked nuclear waste dumped by the Silla Dynasty a thousand years ago, move it elsewhere, and safely dispose of it? And spend tens of trillions to do that. How could we agree to that? We can't even pass on good things, so why leave behind such nuclear waste?"

It was mentioned that the half-life of radionuclides varies greatly: Cobalt-60 is about 30 years, Cesium-137 is also about 30 years, but Plutonium-239 is 24,000 years, and Iodine-129 is 15.7 million years. Considering roughly 10 times the half-life as the approximate decay period, this is a geological time scale beyond human management capabilities.

The panelist explained, "Strontium-90 is 30 years, Cobalt-60 has a half-life of 5.2 years, Cesium-137 is about 30 years, Plutonium-239 is 24,000 years. Iodine-129 is 15.7 million years. In the case of plutonium, since its half-life is 24,000 years, multiplying by 10 makes it about 240,000 years. Even for cesium, which is 30 years, it's not something to be happy about, as it lasts 300 years.", emphasizing the severity of the nuclear waste problem.

Such long-term risks demand a fundamental approach that goes beyond simple technological solutions.

It has been confirmed that both the former Soviet Union (now Russia) and South Korea previously dumped nuclear waste in Korea's East Sea (Sea of Japan). This, along with the Northeast Atlantic case, amplifies concerns about the potential risks to domestic marine ecosystems and humanity.

The panelist stated, "A lot of nuclear waste was dumped in Korea's East Sea (Sea of Japan). The Soviet Union and Russia dumped it, and South Korea also dumped it.", mentioning the dumping of nuclear waste in the East Sea.

The possibility of nuclear waste dumped in the deep sea accumulating in humans through deep-sea water or marine food chains has also been raised.

In-depth investigation and countermeasure development for this issue are urgently needed.

After Russia disclosed its nuclear waste dumping in 1993, a joint investigation was conducted by South Korea, Japan, and Russia in 1994 and 1995. Now, a proposal has been made for a trilateral joint investigation by North Korea, South Korea, and Russia into the nuclear waste dumping in the East Sea (Sea of Japan) to improve inter-Korean relations and resolve environmental issues.

The panelist emphasized, "If Russia, North Korea, and South Korea conduct a trilateral joint investigation, it could be another good project to foster reconciliation in inter-Korean relations.", highlighting the potential positive impact of this project on diplomatic relations.

Approximately 30 years have passed since the 1994 joint investigation and 55 years since the nuclear waste dumping, raising calls for an urgent re-investigation into the possibility of corrosion and leakage of waste in the East Sea (Sea of Japan). Even if no abnormal radioactivity was confirmed in past investigations, the possibility of contamination due to the aging of waste containers has increased over time.

The panelist emphasized, "Even if no abnormal radioactivity was confirmed at the time, it is time for an investigation now. 55 years have passed.", stressing the need for a precise investigation of the entire East Sea ecosystem, including seawater, sediments, and marine life.

The panelist emphasized, "Even if no abnormal radioactivity was confirmed at the time, it is time for an investigation now. 55 years have passed.", stressing the need for a precise investigation of the entire East Sea ecosystem, including seawater, sediments, and marine life.

Criticism has been raised that so-called developed countries are polluting the entire world while forming a cartel among themselves regarding nuclear waste. Civil society, along with the media, must monitor such cartels and demand that the government allocate budget to solving the nuclear waste problem instead of wasting money on unnecessary projects.

One panelist raised their voice, stating, "These so-called developed countries are polluting the entire world and are practically forming a cartel among themselves. Civil society must demand that they stop wasting money on useless things and spend it on issues like this."

In conjunction with this, there was also a call to re-evaluate the economic viability and safety of the SMR (Small Modular Reactor) project to seek fundamental solutions to the nuclear waste problem.

Plans have been announced to re-explore the status of nuclear waste dumped off the coast of Ulleungdo. This investigation will aim to precisely re-identify the waste's location and directly visually confirm its corrosion and leakage status using a deep-sea submarine.

An official explained, "We need to re-explore the waste's location, especially in the inventory, confirm its state of corrosion, investigate sediments, assess radiation impact on benthic organisms, and even confirm whether it can directly affect the ecosystem."

Additionally, the plan includes analyzing radionuclides to evaluate the radiation impact on surrounding sediments and benthic organisms, and investigating the direct impact on the overall marine ecosystem.

With the official formation of an expert committee dedicated to high-level nuclear waste issues, responses are expected to gain further momentum. In addition to the existing nine members, experts with enhanced capabilities will be added, strengthening the expertise and capacity for solving the nuclear waste problem.

The panelist emphasized the importance of the committee's activities, stating, "With the expert committee formed, it will gain more momentum and be able to work effectively."

This is regarded as an important measure to minimize nuclear waste generation and demonstrate a responsible attitude towards future generations.