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1951 - Beginning of the Nuclear Power age. To date, how to safely dispose of the highly radioactive nuclear waste has never been solved !!!

nuclear_waste_canisters July 2015 - 30 countries are operating 438 nuclear power stations and 67 new nuclear plants are under construction in 15 countries. The navy and military also use nuclear reactors for propulsion and nuclear weapons. Consequently, large amount of nuclear radioactive waste by-product is produced every year - and piling up. Not all countries are adequately equipped to store or dispose of their own radioactive waste. Some countries are limited in resources, area, or have unfavourable geology. To date, most countries are struggling in developping a permanent strategy for long-term disposal of nuclear waste. Spent nuclear fuel and by-product plutonium wastes require well-designed storage for periods ranging from tens of thousands to a million year (that long before it starts to decay). There is general agreement that placing spent nuclear fuel in repositories hundreds of meters below the surface would be safer than CURRENT interim surface or sub-surface storage. However, land-based geological storage sites will not have the capacity to store all the waste that will be generated in future decades.


High and Low-level waste (HLW) is produced by nuclear reactors. Spent fuel is highly radioactive and hot. HLW accounts for over 95% of the total radioactivity produced in the process of nuclear electricity generation. The amount of HLW worldwide is currently increasing by about 12,000 metric tons every year, which is the equivalent to about 100 double-decker buses or a two-story structure with a footprint the size of a basketball court . A 1000-MW nuclear power plant produces about 27 tonnes of spent nuclear fuel (unreprocessed) every year. In 2010, there was a very roughly estimated 250,000 tons of nuclear HLW to be stored (excluding escaped amounts into the environment from accidents or tests). Japan is estimated to hold 17,000 tons of HLW in storage in 2015. Specially designed interim surface or sub-surface storage of radioactive waste facilities are currently used in many countries pending the availability of a long-term disposal option. Big problem is that what was initially meant to be an "interim" storage is now ....permanent due to desperately slow progress on finding permanent deep land-based sites. There are concerns that over ground existing fuel waste containers are beginning to degrade. "Recognising that long-term management options may require significant time to be achieved, interim storage arrangements may need to be extended beyond the time periods originally envisaged". (World Nuclear Association, January 2016) Safeguards are also required to ensure that neither plutonium nor highly enriched uranium can be pillaged for terrorist activities. The International Atomic Energy Agency (IAE) says there is "a persistent problem with the illicit trafficking in nuclear and other radioactive materials, thefts, losses and other unauthorized activities". The IAEA Illicit Nuclear Trafficking Database notes 1,266 incidents reported by 99 countries over the last 12 years, including 18 incidents involving enriched plutonium trafficking.

Now may be the time to reconsider the deep sea...

Knowledge about marine eco-systems and sea-bed formation have vastly evolved since the 70's era when the 1972 London Dumping Convention was setup prohibiting dumping of nuclear waste at sea - Convention in force until 2018, after which the sub-seabed disposal option can be revisited at 25-year intervals. However, dumping still occurs illegally everywhere! The oceans have a vastly greater dilution capacity for limiting radioactive emissions than any single land site in the event of accidental leaks and, is unlikely to be disturbed either geologically or by human activity. In view of the controversies and political posturing on land-based disposal of nuclear waste, now may be the time to reconsider the sea (specifically seabed formation) as a possible solution to the ever mounting nuclear waste temporarily stored over ground; a time bomb! Investigating in sea-based solutions makes sense because they are particularly suited to international cooperation.

Sub-Seabed Stable Clay Formations

Sub-Seabed clay formations within stable (predictable) deep-sea regions away from earthquakes and volcanism tectonic plates and productive surface waters (nutrient-rich) have properties that might serve to permanently isolate radioactive waste. The most important characteristics of such clays are their uniformity, low permeability, very high retention capacity and potential for self-healing when disturbed. The most attractive abyssal clay formation covers nearly 30% of the sea floor and hence 20% of the earth's surface.

International group of scientists conducted experiments from 1974 to 1986 that suggested that any leakage from waste containers placed ten meters below the seabed could conceivably remain sealed in clays and muds for millions of years. For example, the large undersea plain, some 600 miles north of Hawaii, stable for some 65 million years, received special attention. American Researchers found that the clay muds in such sub-seabed formations had a high capacity for binding radionuclides, so that any leakage would be likely to remain within the clay for millions of years, by which time radioactive emissions would decline to natural background levels. Therefore, restarting investigation into sub-seabed disposal in stable clay formations make sense and is a way to develop a fallback alternative to geological disposal on land. The biodiversity at such depth limited to species of bacteria, protozoans, and invertebrates (worms, crustaceans and molluscs) that do not migrate to the upper marine food chain. The possibility of creating an international consortium that would ensure that all high-level nuclear waste from every country in the world would be buried in a single sub-seabed storage area seems promising.

Scientists have also considered disposing of nuclear waste by using modern drilling technologies to drill bore holes deep into the seabed, place canisters of SNF (Spent Nclear Fuel) inside, and pack the holes with sediment. Preliminary research has suggested that the risk of radioactive contamination of the marine environment would be low, considering the significant depths that drilling could achieve as well as the thick clays on the ocean floor. For example, waste handlers could dispose of SNF in holes drilled to 800 meters underneath the ocean floor, with SNF stacked in the holes up to about 300 meters beneath the seabed. Corrosion-resistant containers could help seal the SNF. Deep burial of SNF through drilling could be advantageous because the clays on the ocean floor have - low permeability to water, a high adsorption capacity for [radioactive waste] and a natural plasticity that enables the ooze to seal up any cracks or rifts that might develop around a waste container. SNF disposal in bore holes could be appropriate for certain radioactive material that has a long period of radioactive decay. Experiments have suggested that if SNF canisters in bore holes were to rupture, the radioactive material would not migrate more than a few meters from a breached canister after even 100,000 years because the thick clays on the ocean floor would prevent the waste from moving.

nuclear_subduction_fault Burial in Subduction Faults A second sub-seabed option has received little attention but deserves careful consideration: burying canisters of nuclear waste in Subduction Faults that would carry the waste downward toward the Earth’s mantle. This approach possesses the virtue of being very permanent, As the subduction fault would carry the canisters down at a rate of, say, 10 cm per year, the chances of any release of radionuclides into the biosphere would become increasingly remote.

A California firm, Permanent RadWaste Solutions, has pursued the technology for this option. In addition to the bottom-crawling submarine for digging the holes and delivering the waste, this company has developed a canister technology that becomes more tightly sealed and resistant as the outside pressure increases during the descent of the canister toward the mantle. Some observers object that earthquake or volcanic activity could cause the canister to leak, and the radioactive waste would spew into the sky or onto the surface. However, it is possible to place the canisters in the parts of a subduction zone where there is no volcanic activity, so that they will take millions of years to migrate to less stable parts, at a time when their level of radioactivity will no longer surpass that of the natural background. As with the stable clay approach, it would be possible to bore deep holes into the subduction faults in order to get the waste as deep as possible, even though the danger of leakage upward to the seafloor appears to be minimal. Radionuclides are heavier than water, so there is also no reason why they should migrate upward to the ocean's surface, especially since there is no evidence that bottom-dwelling marine species are concentrated upward into a food pyramid that leads to the surface.

Since governments appear to lack the political will to pursue such approaches, international organizations, companies, foundations, NGOs and ENVIRONMNTALISTS need to begin to support research on Sub-Seabed Disposal. Relying, as we now do, on dozens of nuclear countries each to develop and maintain secure geological disposal sites for nuclear waste is a thoughtless, wasteful and dangerously irresponsible. The ultimate goal should be to devise a nuclear waste solution (not necessarily a sea-based one) that will gain international adherence and become the shared global long-term one for all High-Level Waste, and perhaps for Low-Level Waste as well.

The United States has not seriously considered sub-seabed disposal of spent nuclear fuel (SNF) since 1986, when it ceased funding an international team of scientists known as the Seabed Working Group. 190 This group consisted of about 200 researchers from ten different nations and received significant funding during its active years. 191 The group concluded its work with a call for further research after preliminary testing from 1976 to 1986 at about six sites in the Atlantic and Pacific oceans showed promise for sub-seabed burial of SNF in ocean floor sediment. The United States, which provided most of the group’s funding, withdrew its support in favor of land-based SNF disposal methods around the time that Congress selected Yucca Mountain as a national SNF repository.

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....page updated January 2017


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Less than 1% of the total power generated becomes usable electricity

What’s noteworthy about nuclear power is that not a lot of the total energy in a fuel rod is actually utilized and turned into electric power. In fact, less than 1% of the total power generated becomes usable electricity. Therefore, the other 99% has to be treated or allowed to decay in a safe way. The best way to do this, economically, is to store it underground in stable areas for thousands of years.

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Sub-Seabed Solution

Experiments conducted by this international team of scientists from 1974 to 1986 support Hollister's opinion that the sticky mud and clays that blanket the mid-ocean basins may provide the best burial grounds yet proposed for nuclear waste. These tests suggest that if waste canisters were deposited just ten meters below the ocean floor, any toxic substances that leaked out would be bound up by the clays for millions of years. Deeper interment, at 100 meters or more, could easily be managed, providing an even greater margin of safety. "The stuff sticks to the mud and sits there like heavy lead," Hollister maintains.
"Nothing's going to bring it into the biosphere, unless we figure out how to reverse gravity."

Interresting reading; go to website for full text.
www.theatlantic.com