Ocean disposal of radioactive waste


From 1946 through 1993, thirteen countries used ocean disposal or ocean dumping as a method to dispose of nuclear/radioactive waste. 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. Since 1993, ocean disposal has been banned by international treaties.
However, according to the United Nations, some companies have been dumping radioactive waste and other hazardous materials into the coastal waters of Somalia, taking advantage of the fact that the country had no functioning government from the early 1990s onwards. According to one official at the UN, this caused health problems for locals in the coastal region and posed a significant danger to Somalia's fishing industry and local marine life.
"Ocean floor 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.

History

Data are from IAEA-TECDOC-1105, pages 3–4.
Data are from IAEA-TECDOC-1105. 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 – 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 of radioactive waste at over 100 ocean sites, as measured in initial radioactivity at the time of dump.
For comparison:
Data are from IAEA-TECDOC-1105.

Liquid waste

Waste typeAtlanticPacific OceanArctictotalnote
Reactors with spent fuelNilNil36,87636,876
Reactors w/o fuel1,2211661431,530
Low level solid44,04382158545,449
Low level liquid<0.0014597651,223
Total45,264144538,36985,078

Dump sites

Data are from IAEA-TECDOC-1105.

Arctic

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, total of 222,000 m3 including reactors and spent fuel.

North Atlantic

Dumping occurred from 1948 to 1982. The UK accounts for 78% of dumping in the Atlantic, followed by Switzerland, the United States and Belgium. 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.

Pacific Ocean

The Soviet Union 874 TBq, US 554 TBq, Japan 15.1 TBq, New Zealand 1+ TBq and unknown amount by South Korea. 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 is not included.

Sea of Japan

The Soviet Union dumped 749 TBq. Japan dumped 15.1 TBq south of main island. South Korea dumped 45 tonnes.

Environmental impact

Data are from IAEA-TECDOC-1105.

Arctic Ocean

Joint Russian-Norwegian expeditions 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.

North-East Atlantic Ocean

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.

North-East Pacific Ocean, North-West Atlantic Ocean dump sites of USA

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 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.

North-West Pacific Ocean dump sites of the Soviet Union, Japan, Russia, and Korea

The joint Japanese-Korean-Russian expedition concluded that contamination resulted mainly from global fallout.