 Types of radioactive waste |
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 Types of radioactive waste
The management of radioactive waste in such a way as to pose no threat to health is much more than simply a technical issue, and has become an ethical and political issue for society as a whole. Technical solutions already exist for all types of waste, and must be clearly explained.
AREVA has adopted a policy of openness, receptiveness and dialog with all its stakeholders
Where does radioactive waste come from?
The majority of radioactive waste (two-thirds in terms of volume) comes from the nuclear power generating industry as a result of the combustion of fuel assemblies in nuclear power plants.
This proportion of radioactive waste is processed in fuel cycle installations. It consists of:
 waste resulting directly from used fuel, which consists essentially of the uranium fission products formed during the time the fuel was used inside the nuclear power reactor
"technological" waste related to cycle installation operation (including reactor operation), maintenance work and operational tasks (spare parts, tools, coveralls, overshoes, gloves, wipes, etc.)
waste from the dismantling of decommissioned nuclear installations.
Radioactive waste also originate from (in decreasing order of volume):
research
national defense activities
hospitals, with the majority coming from radiotherapy and medical imaging
industrial processes, such as X-ray inspection of pipeline welds.
Half-life
Every radioactive element has a “half-life”, which is the period of time over which its level of radioactivity halves: for example, half the atoms contained in a sample of Cobalt 60 will disintegrate naturally in 5 years. The half-life of Cesium 137 is 30 years, which means that after 60 years, its level of radioactivity will have fallen to one quarter of its initial value, then to one eighth after 90 years, and so on.
It is therefore possible to calculate that after ten half-lives (300 years), the level of radioactivity contained in Cesium 137 will be one thousandth of its initial intensity.
Radioactive half-lives vary considerably from atom to atom, and cover a very broad range. Here are a few examples: 24 seconds for Silver 109, 10 minutes for Nitrogen 13, 6 hours for Cobalt 57, 8 days for Iodine 131, 53 days for Beryllium 7, 1,600 years for Radium 221, 5,730 years for Carbon 14 (which is used to date archaeological finds) and 24,110 years for Plutonium 239.
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Responsible management of radioactive waste |
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Responsible management of radioactive waste
The difference between storage and final disposal
In the nuclear industry, there is a very significant difference between the storage of waste and its final disposal. Storage refers to a temporary situation during which the waste concerned is awaiting conditioning or is already conditioned and awaiting shipping to a final disposal center. Final disposal is a future definitive situation, although it may incorporate a certain degree of reversibility.
What is storage?
This term is used where:
 the used fuel is stored temporarily in a specific location prior to recycling (when the fuel is withdrawn from the reactor and is immersed in a cooling pond)
waste, and specifically vitrified waste, are stored temporarily in a specific location whilst awaiting shipment to a disposal facility.
And disposal?
This term is used where the waste and used fuel concerned are intended for final disposal. |
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There is in France, a surface storage facility for low-level and short-life waste in operation in the Aube region. Other countries have opted for shallow subterranean solutions. The questions are more complex for highly radioactive and long-life waste (final waste) due to their higher toxicity over significant periods extending to tens of thousands of years. Their radioactivity also gives off significant levels of heat, requiring the implementation of special measures. Conditioned as part of the used nuclear fuel treatment process, this final waste is compacted and vitrified before being stored under strict supervision whilst awaiting the establishment of a final disposal facility.
Possible solutions
Ever since the future of nuclear waste became an increasingly-pressing issue, a broad spectrum of solutions have been considered, from disposal beneath the polar icecap to burial on small desert islands… although deep sea immersion was initially considered as the most realistic option.
Eight European countries (UK, Germany, Italy, Sweden, Belgium, Switzerland, The Netherlands and France) used the immersion route for low-level and medium-level radioactive waste over a 30-year period commencing in the late 1940s. France, for one, has totally ceased this type of activity since 1969.
On November 12, 1993, the signatories to the London International Convention imposed a total and permanent ban on the immersion of radioactive waste in the world’s oceans
As far as high-level radioactive waste is concerned, the solution currently recommended by the experts of the AEIA and the OECD is deep geological disposal. Under this arrangement, packaged waste would be stored several hundred meters below the surface in geological structures which, to the best of current knowledge, will be subject to no geological movement for millions of years. Other important criteria include the absence of free water and very low levels of permeability (there must be no water circulating through the rock, which could carry radioactive elements).
Uranium and plutonium are not waste
The French law of June 2006 seeks to avoid any confusion between radioactive waste and nuclear material.
Nuclear material
A nuclear material is a radioactive substance for which a subsequent use is planned or envisaged. This definition applies, for example, to the plutonium and uranium recovered from used fuel treatment by the AREVA facility at La Hague.
Nuclear waste
Where no future use is planned or envisaged, the substance concerned is treated as waste. Where it originates from another country, it must be returned to its country of origin. This is the case with the final waste conditioned and stored on the site of La Hague. |
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What is the current legislation regarding radioactive waste disposal in France? |
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What is the current legislation regarding radioactive waste disposal in France?
The legislation governing the management of nuclear materials and radioactive waste was adopted by the French Parliament on June 28, 2006, and sets out a series of solutions and a timetable for the management of radioactive waste. Its aim is to protect the environment and future generations’ health.
What does the law say? A few excerpts
The law prohibits the final disposal of foreign radioactive waste on French soil.
The law requires the preparation of a national plan for the management of radioactive waste and recyclable materials. This plan is to be updated every three years. This task is the responsibility of the ASN (French Nuclear Safety Authority), whose plan assesses existing management methods, establishes the foreseeable requirement for storage and final disposal facilities and sets the targets to be achieved.
The law also defines guidelines for research into the management of high-level, long-life radioactive waste (separation/conversion, reversible deep geological disposal and storage).
The geological disposal of high-level, long-life radioactive waste requires detailed study and research. Many types of rock are favorable for this purpose, including clay, granite, salt, volcanic tuff and basalt. All countries with nuclear power industries are using underground laboratories to research this option.
The French underground laboratory to research the geological disposal of radioactive waste is located in the Bure district of the département of Meuse. The geological structure being studied here is a 130-meter thick layer of clay over 150 million years old, which lies at a depth of approximately 500 meters below the surface. The permission granted to ANDRA to build and operate this underground laboratory has been extended to December 31, 2011.
Disposal installations are governed by the necessity to minimize their impact on the environment and public health. According to international recommendations, the impact of disposal facilities must not exceed 0.4 mSv per year. French law imposes a limit of 0.25 mSv per year for all types of disposal facility, whether geological or surface. |
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Yellow cake
7 training campaigns and 99 Japanese trainees since 2001
Yves Martin
