Ocean disposal of radioactive waste

From 1946 through 1993, thirteen countries (fourteen, if the USSR and Russia are considered separately) 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. (London Convention (1972), Basel Convention, MARPOL 73/78)

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 United Nations, 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" (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 UK and Sweden, but never implemented.

Data are from IAEA-TECDOC-1105. page 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 (TBq=10¹²Becquerel) — were the USSR, the UK, Switzerland, the US, Belgium, France, the Netherlands, Japan, Sweden, Russia, New Zealand, Germany, Italy and South Korea. Together, they dumped a total of 85,100 TBq (85.1x10¹⁵Bq) 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.

Mainly at the east coast of Novaya Zemlya at Kara Sea and relatively small proportion at Barentz Sea by USSR. Dumped at 20 sites from 1959–92, total of 222x10³m³ including reactors and spent fuel.

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