From 1946 through 1993, thirteen countries used ocean disposal or ocean dumping as a method to dispose of nuclear/radioactive waste with an approximation of 200,000 tons sourcing mainly from the medical, research and nuclear industry. [1]
The waste materials included both liquids and solids housed in various containers, as well as reactor vessels, with and without spent or damaged nuclear fuel. [2] Since 1993, ocean disposal has been banned by international treaties. (London Convention (1972), Basel Convention, MARPOL 73/78). There has only been the disposal of low level radioactive waste (LLW) thus far in terms of ocean dumping as high level waste has been strictly prohibited.
Ocean floor disposal (or sub-seabed disposal)—a more deliberate method of delivering radioactive waste to the ocean floor and depositing it into the seabed—was studied by the United Kingdom and Sweden, but never implemented. [3]
Data are from IAEA-TECDOC-1105, [2] pages 3–4.
Data are from IAEA-TECDOC-1105. [2] Summary of pages 27–120:
Disposal projects attempted to locate ideal dumping sites based on depth, stability and currents, and to treat, solidify and contain the waste. However, some dumping only involved diluting the waste with surface water, or used containers that imploded at depth. Even containers that survived the pressure could physically decay over time.
The countries involved – listed in order of total contributions measured in TBq (TBq=1012 becquerel) – were the Soviet Union, the United Kingdom, Switzerland, the United States, Belgium, France, the Netherlands, Japan, Sweden, Russia, New Zealand, Germany, Italy and South Korea. Together, they dumped a total of 85,100 TBq (85.1x1015 Bq) of radioactive waste at over 100 ocean sites, as measured in initial radioactivity at the time of dump.
For comparison:
Country | dumped (unit TBq=1012 Bq) | period | num of sites, volume, etc.* | |||
---|---|---|---|---|---|---|
Arctic | Atlantic | Pacific | Total | |||
Soviet Union | 38,369 | 0 | 874 | 39,243 | 1959–1992 [11] | Arctic 20 sites, 222,000 m3 and reactor w or w/o spent fuel; Pacific Ocean (mainly sea of Japan) 12 sites, 145,000 m3 |
UK | 0 | 35,088 | 0 | 35,088 | 1948–82 | NE Atlantic 15 sites, unknown number of containers, 74,052 tons and 18 sites off coast of British isles more than 9.4 TBq |
Switzerland | 0 | 4,419 | 0 | 4,419 | 1969–1982 | NE Atlantic 3 sites, 7,420 containers, 5,321 tons |
USA | 0 | 2,942 | 554 | 3,496 | 1946–70 | Mid/NW Atlantic (9), Gulf of Mexico (2) total 11 sites, 34,282 containers, unknown quantity; Mid/NE Pacific Ocean, total of 18 sites, 56,261 containers, ? tones |
Belgium | 0 | 2,120 | 0 | 2,120 | 1960–1982 | NE Atlantic 6 sites, 55,324 containers, 23,100 tons |
France | 0 | 354 | 0 | 354 | 1967–1969 | NE Atlantic 2 sites, 46,396 containers, 14,300 tons |
Netherlands | 0 | 336 | 0 | 336 | 1967–1982 | NE Atlantic 4 sites, 28,428 containers, 19,200 tons |
Japan | 0 | 0 | 15.08 | 15.08 | 1955–1969 | South of Honshu, 6 sites 15 times, 3,031 containers, 606,000 m3 |
Sweden | 0 | 3.2 | 0 | 3.2 | 1959,61,69 | Baltic sea 1 site, 230 containers, 64 tons; NE Atlantic 1 site, 289.5 containers, 1,080 tons, |
Russia | 0.7 | 0 | 2.1 | 2.8 | 1992–93 | Arctic 3,066 m3; Pacific Ocean 6,327 m3 |
New Zealand | 0 | 0 | 1.04 | 1.04 | 1954–1976 | East coast of New Zealand, 4 sites, 9 containers, 0.62 m3 |
Germany | 0 | 0.2 | 0 | 0.2 | 1967 | NE Atlantic 1 site once, 480 containers, 185 tons |
Italy | 0 | 0.2 | 0 | 0.2 | 1969 | NE Atlantic 1 site, 100 containers, 45 tons |
South Korea | 0 | 0 | no data | 1968–1972 | Sea of Japan, 1 site 5 times?, 115 container, 45 tons | |
Total | 38,369 | 45,262 | 1,446 | 85,077 | Subtotal of all volume reported is 982,394 m3. | |
*Some countries report the mass and volume of disposed waste and some just tonnage. The US did not report tonnage or volume of 90,543 containers. |
Data are from IAEA-TECDOC-1105. [2] : 6–7, 14
Waste type | Atlantic | Pacific Ocean | Arctic | total | note |
---|---|---|---|---|---|
Reactors with spent fuel | Nil | Nil | 36,876 | 36,876 | |
Reactors w/o fuel | 1,221 | 166 | 143 | 1,530 | |
Low level solid | 44,043 | 821 | 585 | 45,449 | |
Low level liquid | <0.001 | 459 | 765 | 1,223 | |
Total | 45,264 | 1445 | 38,369 | 85,078 |
Data are from IAEA-TECDOC-1105. [2] : 27–120 There are three dump sites in the Pacific Ocean.
Mainly at the east coast of Novaya Zemlya at Kara Sea and relatively small proportion at Barents Sea by the Soviet Union. Dumped at 20 sites from 1959 to 1992, [11] total of 222,000 m3 including reactors and spent fuel.
Dumping occurred from 1948 to 1982. The UK accounts for 78% of dumping in the Atlantic (35,088 TBq), followed by Switzerland (4,419 TBq), the United States (2,924 TBq) and Belgium (2,120 TBq). Sunken Soviet nuclear submarines are not included; see List of sunken nuclear submarines
There were 137,000 tonnes dumped by eight European countries. The United States reported neither tonnage nor volume for 34,282 containers.
The Soviet Union 874 TBq, US 554 TBq, Japan 606.2 Tonnes, New Zealand 1+ TBq. 751,000 m3 was dumped by Japan and the Soviet Union. The United States reported neither tonnage nor volume of 56,261 containers.
Dumping of contaminated water at the 2011 Fukushima nuclear accident (estimate 4,700–27,000 TBq) is not included.
The Soviet Union dumped 749 TBq. Japan dumped 15.1 TBq south of main island. South Korea dumped 45 tonnes (unknown radioactivity value).
Data are from IAEA-TECDOC-1105. [2] : 7
Joint Russian-Norwegian expeditions (1992–94) collected samples from four dump sites. At immediate vicinity of waste containers, elevated levels of radionuclide were found, but had not contaminated the surrounding area.
Dumping was undertaken by UK, Switzerland, Belgium, France, the Netherlands, Sweden, Germany and Italy. IAEA had been studying since 1977. The report of 1996, by CRESP suggests measurable leakages of radioactive material, and, concluded that environmental impact is negligible.
These sites are monitored by the United States Environmental Protection Agency and US National Oceanic and Atmospheric Administration. So far, no excess level of radionuclides was found in samples (sea water, sediments) collected in the area, except the sample taken at a location close to disposed packages that contained elevated levels of isotopes of caesium and plutonium.
The joint Japanese-Korean-Russian expedition (1994–95) concluded that contamination resulted mainly from global fallout. The USSR dumped waste in the Sea of Japan. Japan dumped waste south of the main island.
The first conversations surrounding dumping radioactive waste into the ocean began in 1958 at the United Nations Law of the Sea Conference (UNCLOS). [12] The conference resulted in an agreement that all states should actively try to prevent radioactive waste pollution in the sea and follow any international guidelines regarding the issue. [12] The UNCLOS also instigated research into the issues radioactive waste dumping caused. [12]
However, by the late 1960s to early 1970s, millions of tons of waste were still being dumped into the ocean annually. [13] By this time, governments began to realize the severe impacts of marine pollution, which led to one of the first international policies regarding ocean dumping in 1972 – the London Convention. [13] The London Convention's main goals were to effectively control sources of marine pollution and take the proper steps to prevent it from happening, mainly accomplishing this by banning specific substances from being dumped in the ocean. [13] [14] The most recent version of the London Convention now bans all materials from marine dumping, except a thoroughly researched list of certain wastes. [13] [14] It also prohibits waste from being exported to other countries for disposal, as well as incinerating waste in the ocean. [13] While smaller organizations like the Nuclear Energy Agency of the European Organization for Economic Cooperation and Development have produced similar regulations, the London Convention remains the central international figure of radioactive waste policies. [12]
Although there are many existing regulations that ban ocean dumping, it is still a prevalent issue. Different countries enforce the ban on radioactive waste dumping on different levels, resulting in an inconsistent implementation of the agreed upon policies. [13] Because of these discrepancies, it is hard to judge the effectiveness of international regulations like the London Convention. [13]
Ocean floor disposal is a method of sequestering radioactive waste in ocean floor sediment where it is unlikely to be disturbed either geologically or by human activity.
Several methods of depositing material in the ocean floor have been proposed, including encasing it in concrete and as the United Kingdom has previously done, dropping it in torpedoes designed to increase the depth of penetration into the ocean floor, or depositing containers in shafts drilled with techniques similar to those used in oil exploration.[ citation needed ]
Ocean floor sediment is saturated with water, but since there is no water table per se and the water does not flow through it the migration of dissolved waste is limited to the rate at which it can diffuse through dense clay. This is slow enough that it could potentially take millions of years for waste to diffuse through several tens of meters of sediment so that by the time it reaches open ocean it would be highly dilute and decayed. Large regions of the ocean floor are thought to be completely geologically inactive and it is not expected that there will be extensive human activity there in the future. Water absorbs essentially all radiation within a few meters provided the waste remains contained.
One of the problems associated with this option includes the difficulty of recovering the waste, if necessary, once it is emplaced deep in the ocean. Also, establishing an effective international structure to develop, regulate, and monitor a sub-seabed repository would be extremely difficult.
Beyond technical and political considerations, the London Convention places prohibitions on disposing of radioactive materials at sea and does not make a distinction between waste dumped directly into the water and waste that is buried underneath the ocean's floor. It remained in force until 2018, after which the sub-seabed disposal option can be revisited at 25-year intervals.
Depositing waste, in suitable containers, in subduction zones has also been suggested. Here, waste would be transported by plate tectonic movement into the Earth's mantle and rendered harmless through dilution and natural decay. Several objections have been raised to this method, including vulnerabilities during transport and disposal, as well as uncertainties in the actual tectonic processes. [15]
Radioactive waste is a type of hazardous waste that contains radioactive material. Radioactive waste is a result of many activities, including nuclear medicine, nuclear research, nuclear power generation, nuclear decommissioning, rare-earth mining, and nuclear weapons reprocessing. The storage and disposal of radioactive waste is regulated by government agencies in order to protect human health and the environment.
The nuclear fuel cycle, also called nuclear fuel chain, is the progression of nuclear fuel through a series of differing stages. It consists of steps in the front end, which are the preparation of the fuel, steps in the service period in which the fuel is used during reactor operation, and steps in the back end, which are necessary to safely manage, contain, and either reprocess or dispose of spent nuclear fuel. If spent fuel is not reprocessed, the fuel cycle is referred to as an open fuel cycle ; if the spent fuel is reprocessed, it is referred to as a closed fuel cycle.
Radioactive contamination, also called radiological pollution, is the deposition of, or presence of radioactive substances on surfaces or within solids, liquids, or gases, where their presence is unintended or undesirable.
The Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter 1972, commonly called the "London Convention" or "LC '72" and also abbreviated as Marine Dumping, is an agreement to control pollution of the sea by dumping and to encourage regional agreements supplementary to the convention. It covers the deliberate disposal at sea of wastes or other matter from vessels, aircraft, and platforms. It does not cover discharges from land-based sources such as pipes and outfalls, wastes generated incidental to normal operation of vessels, or placement of materials for purposes other than mere disposal, providing such disposal is not contrary to aims of the convention. It entered into force in 1975. As of September 2016, there were 89 Parties to the convention.
Dounreay is a small settlement and the site of two large nuclear establishments on the north coast of Caithness in the Highland area of Scotland. It is on the A836 road nine miles west of Thurso.
Marine debris, also known as marine litter, is human-created solid material that has deliberately or accidentally been released in seas or the ocean. Floating oceanic debris tends to accumulate at the center of gyres and on coastlines, frequently washing aground, when it is known as beach litter or tidewrack. Deliberate disposal of wastes at sea is called ocean dumping. Naturally occurring debris, such as driftwood and drift seeds, are also present. With the increasing use of plastic, human influence has become an issue as many types of (petrochemical) plastics do not biodegrade quickly, as would natural or organic materials. The largest single type of plastic pollution (~10%) and majority of large plastic in the oceans is discarded and lost nets from the fishing industry. Waterborne plastic poses a serious threat to fish, seabirds, marine reptiles, and marine mammals, as well as to boats and coasts.
Caesium-137, cesium-137 (US), or radiocaesium, is a radioactive isotope of caesium that is formed as one of the more common fission products by the nuclear fission of uranium-235 and other fissionable isotopes in nuclear reactors and nuclear weapons. Trace quantities also originate from spontaneous fission of uranium-238. It is among the most problematic of the short-to-medium-lifetime fission products. Caesium-137 has a relatively low boiling point of 671 °C (1,240 °F) and easily becomes volatile when released suddenly at high temperature, as in the case of the Chernobyl nuclear accident and with atomic explosions, and can travel very long distances in the air. After being deposited onto the soil as radioactive fallout, it moves and spreads easily in the environment because of the high water solubility of caesium's most common chemical compounds, which are salts. Caesium-137 was discovered by Glenn T. Seaborg and Margaret Melhase.
A deep geological repository is a way of storing hazardous or radioactive waste within a stable geologic environment, typically 200–1,000 m below the surface of the earth. It entails a combination of waste form, waste package, engineered seals and geology that is suited to provide a high level of long-term isolation and containment without future maintenance. This is intended to prevent radioactive dangers. A number of mercury, cyanide and arsenic waste repositories are operating worldwide including Canada and Germany. Radioactive waste storage sites are under construction with the Onkalo in Finland being the most advanced.
The Power Reactor and Nuclear Fuel Development Corporation (PNC) or 動燃 for short, was a Japanese nuclear energy research organization established 2 October 1967 with the Atomic Fuel Corporation as its parent organization and disbanded in 1998 to be restructured as the Japan Nuclear Cycle Development Institute. The organization specialized in special Breeder reactors and the Advanced Thermal Reactor. It also owned a nuclear reprocessing facility and its activities included uranium exploration in Australia and disposal of high-level waste.
Nuclear power has various environmental impacts, both positive and negative, including the construction and operation of the plant, the nuclear fuel cycle, and the effects of nuclear accidents. Nuclear power plants do not burn fossil fuels and so do not directly emit carbon dioxide. The carbon dioxide emitted during mining, enrichment, fabrication and transport of fuel is small when compared with the carbon dioxide emitted by fossil fuels of similar energy yield, however, these plants still produce other environmentally damaging wastes. Nuclear energy and renewable energy have reduced environmental costs by decreasing CO2 emissions resulting from energy consumption.
The Fukushima nuclear accident was a major nuclear accident at the Fukushima Daiichi nuclear power plant in Ōkuma, Fukushima, Japan which began on 11 March 2011. The proximate cause of the accident was the 2011 Tōhoku earthquake and tsunami, which resulted in electrical grid failure and damaged nearly all of the power plant's backup energy sources. The subsequent inability to sufficiently cool reactors after shutdown compromised containment and resulted in the release of radioactive contaminants into the surrounding environment. The accident was rated seven on the INES by NISA, following a report by the JNES. It is regarded as the worst nuclear incident since the Chernobyl disaster in 1986, which was also rated a seven on the INES.
The radiation effects from the Fukushima Daiichi nuclear disaster are the observed and predicted effects as a result of the release of radioactive isotopes from the Fukushima Daiichii Nuclear Power Plant following the 2011 Tōhoku 9.0 magnitude earthquake and tsunami. The release of radioactive isotopes from reactor containment vessels was a result of venting in order to reduce gaseous pressure, and the discharge of coolant water into the sea. This resulted in Japanese authorities implementing a 30-km exclusion zone around the power plant and the continued displacement of approximately 156,000 people as of early 2013. The number of evacuees has declined to 49,492 as of March 2018. Radioactive particles from the incident, including iodine-131 and caesium-134/137, have since been detected at atmospheric radionuclide sampling stations around the world, including in California and the Pacific Ocean.
Landysh is a floating facility for processing contaminated water produced when decommissioning nuclear submarines. It was built in Russia with funds from Japan as part of an agreement on nuclear arms disposal, but has not left the wharf. Japan requested that Russia send Landysh to help in the aftermath of the Fukushima Daiichi nuclear disaster.
The Fukushima disaster cleanup is an ongoing attempt to limit radioactive contamination from the three nuclear reactors involved in the Fukushima Daiichi nuclear disaster that followed the earthquake and tsunami on 11 March 2011. The affected reactors were adjacent to one another and accident management was made much more difficult because of the number of simultaneous hazards concentrated in a small area. Failure of emergency power following the tsunami resulted in loss of coolant from each reactor, hydrogen explosions damaging the reactor buildings, and water draining from open-air spent fuel pools. Plant workers were put in the position of trying to cope simultaneously with core meltdowns at three reactors and exposed fuel pools at three units.
The Fukushima Daiichi reactor, was 1 out of 4 reactors seriously affected during the Fukushima Daiichi nuclear disaster on 11 March 2011. Overall, the plant had 6 separate boiling water reactors originally designed by General Electric (GE), and maintained by the Tokyo Electric Power Company (TEPCO). At the time of the earthquake, Reactor 4 had been de-fueled while 5 and 6 were in cold shutdown for planned maintenance. Unit 1 was immediately shut down automatically after the earthquake, and emergency generators came online to control electronics and coolant systems. However, the tsunami following the earthquake quickly flooded the low-lying rooms in which the emergency generators were housed. The flooded generators failed, cutting power to the critical pumps that must continuously circulate coolant water through the reactor core. While the government tried pumping fresh water into the core, it was already too late due to overheat. In the hours and days that followed, Unit 1 experienced a full meltdown.
The Fukushima Daiichi reactor, was 1 out of 4 reactors seriously affected during the Fukushima Daiichi nuclear disaster on 11 March 2011. Overall, the plant had 6 separate boiling water reactors originally designed by General Electric (GE), and maintained by the Tokyo Electric Power Company (TEPCO). In the aftermath, Unit 3 experienced hydrogen gas explosions and suffered a partial meltdown, along with the other two reactors in operation at the time the tsunami struck. Reactor 4 had been de-fueled while 5 and 6 were in cold shutdown for planned maintenance.
The Fukushima Daiichi nuclear accident genshiryoku hatsudensho jiko) was a series of equipment failures, nuclear meltdowns, and releases of radioactive materials at the Fukushima I Nuclear Power Plant, following the Tōhoku earthquake and tsunami on 11 March 2011. It was the largest nuclear disaster since the Chernobyl disaster of 1986, and the radiation released exceeded official safety guidelines. Despite this, there were no deaths caused by acute radiation syndrome. Given the uncertain health effects of low-dose radiation, cancer deaths cannot be ruled out. However, studies by the World Health Organization and Tokyo University have shown that no discernible increase in the rate of cancer deaths is expected. Predicted future cancer deaths due to accumulated radiation exposures in the population living near Fukushima have ranged in the academic literature from none to hundreds.
Depleted uranium hexafluoride (DUHF; also referred to as depleted uranium tails, depleted uranium tailings or DUF6) is a byproduct of the processing of uranium hexafluoride into enriched uranium. It is one of the chemical forms of depleted uranium (up to 73-75%), along with depleted triuranium octoxide (up to 25%) and depleted uranium metal (up to 2%). DUHF is 1.7 times less radioactive than uranium hexafluoride and natural uranium.
Radioactive water from the Fukushima Daiichi Nuclear Power Plant in Japan began being discharged into the Pacific Ocean on 11 March 2011, following the Fukushima Daiichi nuclear disaster triggered by the Tōhoku earthquake and tsunami. Three of the plant's reactors experienced meltdowns, leaving behind melted fuel debris. Water was introduced to prevent the meltdowns from progressing further. When cooling water, groundwater, and rain came into contact with the melted fuel debris, they became contaminated with radioactive nuclides, such as iodine-131, caesium-134, Caesium-137, and strontium-90.