User:Masaqui/sandbox/Ocean disposal of radioactive waste

Ocean disposal of radioactive waste or Ocean dumping is a method practiced from 1946 to 1993 by many countries to dispose nuclear/radioactive waste. There is a similar but different method studied by UK and Sweden which is Ocean floor disposal (or Sub seabed disposal). Concept of Ocean floor disposal is actively deliver waste to ocean floor and deposit waste within seabed. This method was studied but not practiced.

Overview
Ocean dumping is the first method practiced by early nuclear adapting countries to dispose radioactive waste in second half of 20th century. Then other industrial waste also dumped at sea or river without much concern about environment impacts.

Since first disposal of 1946 by US at the Northeast Pacific Ocean Ocean (80km off coast of California), 13 countries had disposed nuclear waste including liquid and solid waste, reactor vessels with and without spent or damaged nuclear fuel into the oceans until 1993.

Ocean dumping of radioactive waste is not permitted by a number of international agreements. (London Convention (1972), Basel Convention, MARPOL 73/78)

History
Data are from IAEA_tec1105.
 * 1946 First dumping operations (USA) at Northeast Pacific Ocean Ocean (about 80km off the coast of California
 * 1957 First IAEA Advisory Group Meeting on Radioactive Waste Disposal into the Sea
 * 1958 First United Nations Conference on the Law of the Sea (UNCLOS I)
 * 1972 Adoption of the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter (London Convention 1972)
 * 1975 The London Convention 1972 entered into force (Prohibition of dumping of high level radioactive waste.)
 * 1983 Decision on moratorium on low level waste dumping
 * 1988 Assessing the Impact of Deep Sea Disposal of Low-level Radioactive Waste on Living Marine Resources. IAEA Technical Reports Series No. 288
 * 1990 Estimation of Radiation Risks at Low Dose. IAEA-TECDOC-557
 * 1993 Russia reported the dumping of high level nuclear waste including spend nuclear fuel by former USSR.
 * 1994 Feb-20 Total prohibition on radioactive waste disposal at sea came into force

Disposal of 1946-93
Data are from IAEA_tec1105. Disposals were taken place under consideration of; However some of dumping were just done to dilute radioactive waste with surface water, or containers implode at depth. Even containers survive with pressure but its physical structure will decay in time at ocean floor and start leaking radioactive material.
 * locate ideal dumping site for depth, stability and ocean current
 * treatment of radioactive waste, solidification, containment

USSR, UK, Switzerland, US, Belgium, France, Netherlands, Japan, Sweden, Russia, New Zealand, Germany, Italy and Korea had dumped waste at over 100 dumping site.

Total of 85.1x1015 Becquerel(Bq)(initial radioactivity at the time of dump) of radio active waste were disposed at sea.

< other values for comparison >
 * 1986 Chernobyl disaster total release of 5200x1015Bq
 * 2011 Fukushima Daiichi nuclear disaster dumped contaminated water to the sea, TEPCO estimate 4.7x1015Bq、Japanese Nuclear Safety Commission estimate 15x1015Bq 、French Nuclear safety committee estimate 27x1015Bq.
 * One container (net 400kg) of vitrified high level radioactive waste has average of 4x1015Bq (Max 45x1015Bq)

Types of waste and packaging
Data are from IAEA_tec1105.

Liquid waste
 * unpackaged and diluted in surface waters
 * contained in package but not solidified

Solid waste
 * low level waste like resins, filters, material used for decontamination processes, etc., solidified with cement or bitumen and packaged in metal containers
 * unpackaged solid waste, mainly large parts of nuclear installations (steam generators, pumps, lids of reactor pressure vessels, etc.

Reactor vessels
 * without nuclear fuel,
 * containing damaged spent nuclear fuel solidified with polymer agent
 * special container with damaged spent nuclear fuel (icebreaker Lenin by the former Soviet Union)

Locations of dumping
Data are from IAEA_tec1105.

Marksize

0-10TBq;4, 10-100TBq;6, 100-1000TBq;8, 1000-10000TBq;11, over;15

Arctic Ocean dump sites

North Atlantic dump sites

Pacific Ocean

Sea of Japan

Environmental impact
Data are from IAEA_tec1105.

Arctic Ocean dumped by USSR and Russia

The joint Russian-Norwegian expeditions (1992-94) collected sample from four waste dumping sites. at immediate vicinity of waste containers, elevated levels of radionuclide are found, but not contaminated surrounding area.

North-East Atlantic Ocean dumping site

Dumped by UK, Switzerland, Belgium, France, Netherland, Sweden, German and Italy. IAEA had been studied since 1977. in the report of 1996 by CRESP suggests measurable leakages of radioactive material but concluded that environmental impact is negligible.

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

these sites are monitored by US EPA and US National Oceanic and Atmospheric Administration. So far no excess level of radionuclides were found in sample (sea water, sediments) collected in the area, except the sample taken at close location of disposed packages which contained elevated level of isotopes of caesium and plutonium.

North-West Pacific Ocean Ocean dumped by USSR, Japan, Russia and Korea

The joint Japanese-Korean-Russian expedition (1994-95) concluded that contamination are mainly by global fallout.