Category: Nuclear Control

Source: International Atomic Energy Agency – IAEA

Source: International Atomic Energy Agency – IAEA

Japan’s approach for recycling and disposing of soil and radioactive waste from decontamination activities after the 2011 Fukushima Daiichi Nuclear Power Station (FDNPS) accident as currently planned is consistent with IAEA Safety Standards, an International Atomic Energy Agency (IAEA) report released today says.

The findings, presented by the IAEA to Japan’s Minister of the Environment Shintaro Ito today, were the result of a sixteen-month safety review. The IAEA assessed the approach of the Ministry of Environment Japan (MOEJ) to date for the managed recycling and the final disposal of removed soil and radioactive waste against the IAEA Safety Standards. These safety standards serve as a global reference for protecting people and the environment and contribute to a harmonized high level of safety worldwide.

“We appreciate the enormity of the challenge facing Japan in dealing with the aftermath of the 2011 FDNPS accident and we commend the country for requesting our impartial and technical review of its plans,” said IAEA Director General Rafael Mariano Grossi.  “The recycling and disposal of the soil further contributes to the reconstruction of areas affected by the accident.”

About 13 million cubic meters of soil and about 300,000 cubic meters of ash from incineration of organic material was removed as part of decontamination activities in Fukushima Prefecture and stored at an Interim Storage Facility (ISF) covering an area of 16 square kilometres, spanning across the Okuma Town and Futaba Town.

The management of removed soil—enough to fill 11 Tokyo Domes—is governed by a Japanese law which permits the government to repurpose the soil both within and outside of Fukushima Prefecture and for final disposal of the remaining soil to take place outside of the Fukushima Prefecture by 2045.

Japan plans to recycle roughly 75% of the removed soil – the soil which has low levels of radioactivity – by using it, if demonstrated safe, for civil engineering structures including embankments for roads, railways, seawalls, waste treatment sites, coastal protection, agricultural land, and land reclamation. The remaining soil which cannot be recycled will be disposed of permanently and Japan intends to confirm the site selection and disposal process in 2025.

“The IAEA is confident that as the Ministry of the Environment (MOEJ) continues to explore solutions in line with our recommendations, its evolving strategy for recycling and final disposal of removed soil and waste will remain consistent with IAEA Safety Standards,” said Director General Grossi.

In response to Japan’s request in October 2022 for a safety review, an IAEA team – comprised of five IAEA staff and six international experts from Belgium, Germany, Japan, the UK, and the US – conducted three international expert missions in May 2023, October 2023 and February 2024. The IAEA’s review included providing advice and support to Japan from both technical, including safety aspects, and social viewpoints. 

The team of experts recognised the many technical and social challenges facing the MOEJ if it is to implement the managed recycling of removed soil and secure final disposal outside Fukushima Prefecture by 2045.

“The IAEA found the MOEJ’s proactive approach to managing removed soil and waste arising from decontamination activities reflects a commitment to ensuring safety, protecting public health and promoting environmental sustainability in Fukushima Prefecture and beyond,” said Director General Grossi. “The IAEA is committed to engaging with Japan on the managed recycling and the final disposal of removed soil and waste through future follow-up assessments of the MOEJ’s approach.”

Source: International Atomic Energy Agency – IAEA

An International Atomic Energy Agency (IAEA) team of experts today completed a review of long term operational safety of the Koeberg Nuclear Power Plant (NPP) in South Africa.

The Safety Aspects of Long Term Operation (SALTO) follow-up review mission was requested by the plant’s operator, Eskom. Koeberg Units one and two started commercial operation in 1984 and 1985, respectively. Koeberg’s Unit 1 received a license to continue operating until 2044 in July this year, and Eskom is planning to extend operation of Unit 2 until 2045.

Koeberg Nuclear Power Plant is located approximately 30 kilometers north of Cape Town, South Africa, and provides around 5 per cent of the country’s electricity, playing a vital role in reducing reliance on coal. It is the only commercially operating nuclear power station on the African continent. Koeberg is equipped with two pressurized water reactors with a combined capacity of 1934 MW(e), making it a key component of South Africa’s energy infrastructure.

During the 3 to 6 September mission, the SALTO team’s review focused on aspects essential to the safe Long Term Operation (LTO) of both units. The mission reviewed Koeberg NPP’s response to recommendations and suggestions made during an IAEA SALTO mission in 2022, which built upon an initial IAEA pre-SALTO mission held at the plant in 2019.

“The team observed that the plant is addressing the SALTO team’s suggestions and recommendations from the 2022 review,” said team leader and IAEA Nuclear Safety Officer Bryce Lehman. “Based on its efforts, the plant has made significant improvements in ageing management and resolved most of the issues identified in 2022. The plant is on track to complete the remaining items in a reasonable timeframe.”

The team – comprising two experts from the Czech Republic and Slovenia, and two IAEA staff members – said the plant had:

• Updated the LTO programme ensuring that all long-term operation activities are systematically planned, executed on schedule, and aligned with safety and operational standards.
• Completed the revalidation of environmental qualification for qualified cables ensuring that nuclear facility cables remain capable of safely performing under specific environmental conditions over time, despite aging or wear.
• Completed the revalidation of the Time Limited Ageing Analysis (TLAAs) for concrete structures, including the containment TLAA.

The team noted that the plant needs to continue its work to ensure that:

• The plant programmes supporting LTO are fully implemented for the LTO period.
• The containment monitoring system is fully refurbished and remains fully functional during the LTO period.

Plant management expressed a determination to maintain the level of preparedness for safe LTO and to further cooperate with the IAEA in this area.

“For us, this is an integral part of the IAEA’s supporting service to ensure safe operation of the Koeberg reactors during the LTO period for the next 20 years. The IAEA SALTO missions, and technical cooperation, helped to improve our continued focus on safe operation,” said Keith Featherstone, Chief Nuclear Officer, Nuclear Operating Unit, Eskom. “Eskom has worked diligently to demonstrate and ensure the safe operation of the Koeberg plant today and into the future and together with the IAEA carried out four review missions and several technical support discussions. We appreciate the IAEA’s support and the independent review against international safety standards. We will continue to collaborate in the future as part of our drive to continuously improve,” he added.

The team provided a draft report to the plant management and to the South African National Nuclear Regulator (NNR) at the end of the mission. They will have an opportunity to make factual comments on the draft. A final report will be submitted to the plant management, the NNR and the South African Government within three months.

Background

General information about SALTO missions can be found on the IAEA Website. A SALTO peer review is a comprehensive safety review addressing strategy and key elements for the safe long term operation of nuclear power plants. They complement OSART missions, which are designed as a review of programmes and activities essential to operational safety. Neither SALTO nor OSART reviews are regulatory inspections, nor are they design reviews or substitutes for an exhaustive assessment of a plant’s overall safety status.

LTO of nuclear power plants is defined as operation beyond an established time frame determined by the license term, the original plant design, relevant standards, or national regulations. As stated in IAEA safety standards, to maintain a plant’s fitness for service, consideration should be given to life limiting processes and features of systems, structures, and components (SSC), as well as to reasonably practicable safety upgrades to enhance the safety of the plant to a level approaching that of modern plants.

Source: International Atomic Energy Agency – IAEA

IAEA Director General Rafael Mariano Grossi examined a cooling tower at Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) this week to assess the damage it suffered in a major fire last month, the latest incident underlining persistent nuclear safety and security dangers at the site during the military conflict.

The visit to one of the ZNPP’s two cooling towers took place during the Director General’s fifth mission to the sprawling industrial site in southern Ukraine, and two years after he first crossed the frontline to establish a continued presence of IAEA staff at the plant and help prevent a nuclear accident there.

Inside the cooling tower, he saw significant damage on the interior walls, debris and blackened surfaces after ascending about 15 metres up into the massive concrete structure located more than one kilometre away from the six reactors, which are all in cold shutdown and do not currently need the cooling towers to remove residual heat.

While the fire that erupted in the evening of 11 August – belching thick black smoke – did not endanger nuclear safety, it underlined the constant risks the ZNPP is continuing to face in the third year of the armed conflict, with shelling, artillery strikes, drone attacks and other military activities regularly heard in the vicinity of the site.

“It is clear that the cooling tower was damaged by the fire, and it may need to be demolished,” Director General Grossi said. “We will continue to closely look into this matter to try to establish what happened and what the consequences will be. Today was an important step in this work as we were able to see for ourselves the full extent of the damage.”

“Coming a few months after the site was struck by a series of drone attacks, it is yet another incident showing the paramount importance of the IAEA presence at the site for as long as this devastating war goes on. The IAEA will continue to play its indispensable role in helping to avert the threat of a nuclear accident,” he said.

During Wednesday’s mission, he also saw first-hand how the plant is continuing to manage the aftermath of the destruction of the Kakhovka dam in June last year.  In visiting a pumping station of one of the six reactor units, he was able to assess the availability of cooling water in the ZNPP cooling pond, which has now dropped by just over 2 metres since mid-2023. While the water that provides cooling to the six shutdown reactors and other essential nuclear safety services is provided by the 11 groundwater wells, the cooling pond would be a primary water resource in case the wells became unavailable.

In addition, Director General Grossi toured a storage facility located in one of the ZNPP’s special buildings, containing fresh nuclear fuel.

As a key part of his visit, Director General Grossi accompanied a new team of IAEA staff to the site to replace colleagues who had been monitoring the situation at the plant for the past several weeks. It is the 23rd IAEA team at the ZNPP since September 2022.

Before the Director General arrived at the ZNPP, Europe’s largest NPP, he met with President Volodymyr Zelensky in Kyiv, agreeing to expand the IAEA’s assistance to Ukraine by assessing vital energy infrastructure that has increasingly been targeted in missile attacks, with potentially severe implications for nuclear safety and security.

Further underlining the high risks at the ZNPP, the IAEA team stationed at the plant reported that its only remaining 330 kilovolt (kV) backup power line was disconnected on Monday evening, leaving it reliant on a single 750 kV line. Before, the war it had four 750 kV and six 330 kV power lines available. The line was reconnected today, after nearly three days.

Shortly after the disconnection occurred, the IAEA team observed dark smoke in an area close to where the power line was reportedly disconnected, about 3 kilometres away, but it was not immediately clear if these events were linked. The ZNPP said it believed the power line cut was caused by military activities.

The team has continued to conduct walkdowns across the site over the past week, for example visiting the 750 kV open switchyard where they observed ongoing maintenance work, as well as the water sprinkler ponds which receive water from 11 groundwater wells dug after the Kakhovka dam was destroyed. The team confirmed that there is sufficient water available to cool the ZNPP’s shutdown reactors.

Elsewhere in Ukraine, the IAEA teams stationed at the Rivne and South Ukraine NPPs and the Chornobyl site reported that these sites have not yet restored connection to all of their off-site power lines following the widespread military activities on 26 August, targeting electrical substations that are important for nuclear safety. The teams also reported air raid alarms on most days over the past week.

At the Khmelnytskyy NPP, the IAEA team heard drones and gunfire in the early hours of Wednesday morning and were told to shelter. The KNPP and the State Nuclear Regulatory Inspectorate of Ukraine (SNRIU) reported to the IAEA that drones had flown a few kilometres away from the plant. The team at this site rotated on Wednesday.

The IAEA signed an agreement this week with France and Ukraine’s Energoatom regarding support to Ukraine’s NPPs. Ukraine will receive the necessary spare parts for emergency diesel generators at the South Ukraine NPP.  In case of a loss of off-site power, the NPPs rely on such equipment to provide power for continued safe and secure operation. Their maintenance and functionality, including the availability of spare parts, is essential to ensure proper functioning and prevent a nuclear accident due to loss of off-site power. Such assistance was also delivered to Ukraine in 2023.