Nuclear Monitor #939

Wen Bo 

The South China Sea is a tropical marginal sea covering both subtropical and tropical regions.  The area is home to numerous iconic species, including Dugong, Leatherback turtle, Hawksbill turtle, Sperm whale, several species of Beaked whale, Pantropical spotted dolphin, Indo-Pacific humpback dolphin, large fish such as Whale shark, as well as numerous coral species.

As nations surrounding the South China Sea compete for territorial claims and resources such as fisheries and potential oil and natural gas reserves, the region is facing dire ecological and security impacts from growing nuclear activities.

The ultimate dilemma is that nuclear safety requires absolute international transparency and cooperation, yet the South China Sea is characterized by secrecy and geopolitical competition. In the event of a nuclear accident, such as a breach in a nuclear submarine reactor, radioactive leakage from a nuclear power plant or a floating nuclear reactor capsizing in a typhoon, regional states lack the unified legal framework and crisis communication channels needed to prevent an environmental and security crisis.

Expansion of nuclear power plants around the South China Sea

Prior to the year 2000, only two nuclear power plants were operating around the South China Sea: The Maanshan Nuclear Plant (Nuclear No. 3) sits at the southernmost tip of Taiwan on Hengchun Peninsula, Pingtung County; while the Daya Bay Nuclear Power Plant situated in China’s Guangdong Province. Despite the construction of the Philippines’ Bataan Nuclear Power Plant in 1984, its operation was never commenced due to allegations of corruption and concerns over a potential recurrence of the Chernobyl incident. The Bataan Nuclear Power Plant was also constructed near active fault lines and Mount Natib, a potentially active volcano.

Most countries in the Southeast Asian archipelago are located in the frequently earthquake-prone Ring of Fire, so nuclear power has traditionally been a less desirable choice for energy supply. However, to enhance energy security, transition to a low-carbon economy and offset the impact of the blockade of oil tankers in the Strait of Hormuz, countries like Malaysia has now decided to accelerate its exploration of nuclear energy. In March 2026, Malaysian Ministry of Energy Transition and Water confirmed that nuclear power would be a cornerstone of its long-term national electricity strategy.

Vietnam has also announced its intention to resume the development of its previously suspended nuclear power project. In the wake of the energy shortage triggered by the Iran War and the subsequent US easing of sanctions on Russia, the Vietnamese government saw an opportunity to re-establish its relationship with Russia on nuclear cooperation. In late March 2026, the Vietnamese Prime Minister, Pham Minh Chinh, visited Moscow, where the two countries signed an agreement to build a nuclear plant in Vietnam.

However, given Vietnam’s dense population and narrow, strip-shaped geography, the management of high-level radioactive waste from its nuclear power plant would present significant challenges.

China has the largest number of nuclear power plants bordering the South China Sea. Over 10 nuclear power stations are located along the coastline of the provinces of Hainan, Guangxi and Guangdong, discharging routinely liquid effluents containing cumulative concentrations of tritium into local currents under normal operating limits.

A list of Chinese nuclear power plants in the South China Sea region

 Besides, China has successfully tested floating nuclear power plants (FNPPs), which deploy floating nuclear reactors on ships. These plants will be able to provide support to remote islands, oil rigs and desalination plants. However, the deployment of these systems in actual commercial applications may still require resolution of safety, diplomatic and ecological considerations, and may therefore not be anticipated in the near future.

Radioactive pollution in the South China Sea

It is widely acknowledged that the presence of radioactive isotopes in the South China Sea is primarily attributed to the Pacific Proving Ground near the Marshall Islands, as well as to past nuclear tests in the Pacific Ocean. Ocean currents have transported radioactive pollutants such as plutonium-239/240 and iodine-129 to the South China Sea, where they have been detected by researchers. While plutonium levels in seawater demonstrate ongoing transport, plutonium levels in sediment are higher, indicating historical fallout from French and US nuclear tests in the Pacific.

Radioactive materials from the Fukushima Daiichi Nuclear Power Plant, and its ongoing, multi-decade release of ALPS-treated water into the Pacific Ocean would eventually reach the South China Sea via ocean currents. Research indicates that a minor, secondary branch of the current system — heavily influenced by localized, seasonal monsoons and oceanic eddies — slowly transports highly diluted, subsurface water southwestwards through the Luzon Strait pathway.

In Taiwan, Reactor Unit 2 at the Maanshan Nuclear Power Plant was taken offline in May 2025, officially making Taiwan a nuclear-free island. However, as the power shortage crisis worsened, Taipower applied to the Nuclear Safety Commission in March 2026 to restart the Maanshan Power Plant, indicating a reversal of Taiwan’s nuclear phase-out policy.

The Maanshan Power Plant’s cooling system interfaces directly with the Luzon Strait. Decades of marine monitoring in the adjacent Kenting National Park have linked localized summer coral bleaching events directly to the facility’s hot water plumes.

The South China Sea receives a large volume of regular discharges from nuclear power stations operating along China’s coastline. The concentration of isotopes in this body of water is heavily influenced by local tides, river runoff and seasonal, monsoon-driven currents.

Radioactive contamination can bioaccumulate in marine life, threatening the biologically rich ecosystem of the South China Sea and its fishery resources, and ultimately posing a risk to human health.

Radioactive pollution is also generated by the processing of rare earths. In the 1980s, the Bukit Merah radioactive pollution incident in Malaysia resulted in a class action lawsuit against Asian Rare Earth (ARE), a Japan–Malaysia joint venture. Backed by the Consumers’ Association of Penang, local residents successfully compelled ARE to cease operations in 1994.

Following the closure, the ARE’s parent company, Mitsubishi Chemical, spent over US$100 million and more than two decades on a large-scale decommissioning, decontamination and clean-up operation. The 80,000 barrels of radioactive waste were subsequently moved and permanently entombed in a secure repository within the Kledang mountain range in Perak. This has led to ongoing safety and health concerns among Bukit Merah residents.

The Lynas Rare Earth Plant in Gebeng, Pahang of Malaysia has also faced sustained opposition from environmental groups such as Greenpeace Malaysia regarding the handling, storage and potential long-term accumulation of its radioactive residues.

The emergence of nuclear submarine activities in the South China Sea

Apar from being a major marine biodiversity hotspot, the South China Sea has also become a critical and contested arena for nuclear submarine operations. China has established a strategic nuclear “bastion” anchored at its Longpo Naval Base on Hainan Island. This allows its Type 094 and next-generation nuclear submarines to patrol deep regional trenches where they are shielded from acoustic detection.

Located in Yalong Bay in Sanya, Hainan Province, the Longpo Naval Base is China’s largest nuclear submarine base. Construction of the base began at the start of the 21st century, and it has quickly become the country’s most important sea-based nuclear deterrent facility, as well as being the largest of its kind in Asia.

The US Navy also routinely deploys nuclear-powered attack (SSN) and guided-missile (SSGN) submarines to the region to maintain superiority and a naval presence. Vessels such as the USS Ohio have previously conducted missions in the area.

India views China’s nuclear submarines as a threat to its national interests, particularly following the docking of a Chinese nuclear submarine in the Gulf of Aden in February 2014. On 3 April this year, India commissioned its third nuclear submarine, the INS Arihant, to join its Arihant-class fleet.

Should an Indian nuclear submarine cross the Strait of Malacca into the South China Sea in the future, China would undoubtedly view this as a significant strategic provocation. In recent years, there has been an ongoing deepening of naval cooperation between the Philippines and India. In August 2025, the two countries conducted their first joint patrol in the disputed waters of the South China Sea. If the Philippines were to invite India, it is not entirely impossible that an Indian nuclear submarine would sail to the South China Sea.

Australia has no nuclear presence in the South China Sea by far. However, it has joined the AUKUS partnership, which involves acquiring nuclear submarines. This has raised concerns in Malaysia and Indonesia. They fear this could fuel a regional arms race and hinder the establishment of a nuclear-free zone.

Australia plans to host US and UK submarines at the HMAS Stirling base in Western Australia to support maritime operations in the South China Sea. The base near Perth is being developed to support the rotation of US nuclear-powered submarines from 2027 onwards, which will establish it as the primary hub for the maritime presence of Western allies in the region.

Notably, the 1995 Bangkok Treaty established the ASEAN Nuclear-Weapon-Free Zone. This treaty commits the eleven ASEAN member states not to develop, manufacture, acquire, test or possess nuclear weapons. Parties are also prohibited from using, threatening to use, stationing or testing nuclear weapons within the zone. The treaty also forbids the dumping of radioactive waste in the region. The zone encompasses the land territories, territorial seas, continental shelves and exclusive economic zones (EEZs) of all member nations.

Uranium deposits and mining around the South China Sea

Countries bordering the South China Sea have explored their respective uranium potentials. Vietnam’s uranium reserves are estimated to be between 130,000 and 230,000 metric tons. Despite these reserves, Vietnam has primarily relied on imported nuclear fuel for its civil research reactor in Da Lat. The planned Ninh Thuan 1 power project is set to expand Vietnam’s nuclear infrastructure. While initial exploration indicates that the country has sufficient uranium to eventually support domestic fuel processing, the current focus is on constructing power plant and importing fuel in order to avoid the expense of local mining operations.

In the Philippines, coastal explorations in northern Palawan have identified sand deposits in the coastal areas of Ombo and Erawan in San Vicente rich in rare earth elements, thorium and uranium.

Although Malaysia currently has no commercial uranium mines, it is actively advancing its nuclear energy plan and examining its domestic uranium and thorium reserves as potential strategic assets. The country has identified naturally occurring uranium and thorium reserves, primarily as by-products of tin mining and rare earth processing. These are known as ‘amang’. These minerals are found in granitic terrain in states such as Perak, Selangor, Pahang and Johor.

Geological surveys in Malaysia have identified significant ‘fertile granites’ containing up to three times the global average of uranium. The IAEA has also identified six anomalous zones in Peninsular Malaysia, particularly around the Main Range and Bujang Melaka plutons, where uranium mineralization is favorable.

Indonesia holds estimated uranium reserves of over 90,000 tons, according to its National Research and Innovation Agency, primarily located in Sumatra, Kalimantan, West Sulawesi and Bangka Belitung. The country also has approximately 140,000 tons of thorium reserves.

Although historically prohibited, commercial uranium mining and radioactive mineral processing have recently become legally permissible under the Job Creation Law. The Kalan area in Kalimantan has even undergone underground tunnelling exploration. Indonesia aspires to become a leading uranium producer in Southeast Asia and to export to the global uranium market.

Both Guangdong and Guangxi, two provinces in China that border the South China Sea, contain important historical uranium reserves.

The main uranium mining areas of Guangxi are in the northern and north-eastern regions of Guilin, including the Mia’er Mountain and Motianling areas. In fact, China’s first uranium ore was discovered in 1943 by the geologist Nan Yanzong in Zhongshan County of Guangxi. Subsequently, China’s first uranium ore was mined in Honghua Town of Zhongshan County in October 1954.

Guangdong is the cradle of China’s uranium geological exploration and natural uranium industry. The province supplied approximately 67.3% of the nuclear fuel used to develop China’s first atomic bomb. However, the major Shaoguan uranium mine in northern Guangdong has been decommissioned due to resource depletion.

Nowadays, Chinese researchers are developing technology to extract uranium from the South China Sea, utilizing a vast, low-concentration resource to support the country’s rapidly expanding nuclear power sector. Recent breakthroughs, including the creation of a specialized testing platform and the development of new, highly efficient absorbent materials, have made small-scale extraction successful.

Hainan University hosts the State Key Laboratory of Marine Resource Utilization in the South China Sea and is the academic anchor for China’s strategic ambition to mine uranium from the ocean. Led by Professor Wang Ning and Dr Yuan Yihui, Hainan University has pioneered marine uranium capture. The team has developed bifunctional polymeric peptide hydrogels. These materials feature a built-in, broad-spectrum antimicrobial mechanism that repels 99% of marine microorganisms while leaving uranium-binding sites completely unobstructed for harvesting nuclear fuel. Publicized in late 2025, the university developed a triple-channel structural framework that optimizes the flow of seawater through adsorbent materials. This structural design accelerates the transfer of ions, enabling the material to capture uranium at unprecedented speeds in open ocean currents.

Researchers from Lanzhou University and the China National Nuclear Corporation (CNNC) have developed new, highly selective adsorbents that increase the efficiency of uranium-vanadium separation by 40-fold. The CNNC’s large-scale test platform in the South China Sea is operational, enabling material validation in real-world environments. Recent electrochemical methods have been shown to use significantly less energy than conventional methods, reducing costs to around $83/kg.  China plans to have a fully operational, large-scale industrial extraction plant in place by 2050.

Wen Bo set up Greenpeace office in Beijing in year 2001 and developed China Program with Pacific Environment and Global Greengrants Fund