Redevelopment and environmental monitoring of former uranium mines in France
Site redevelopment record/Areas of development
Rehabilitating mine sites after operations
At the end of the operating period, AREVA redevelops and replants mine sites. They are then monitored radiologically and environmentally to watch and control their development. The group also monitors ground movements and erosion resistance. There are two primary purposes for this monitoring:
- To protect public health and safety near the sites, and
- To minimize environmental hazards and impacts.
Since the beginning of the group's mining activities, AREVA has invested more than 300 million Euros to dismantle mining facilities and redevelop mine sites in France, Gabon, the United States and Canada at the end of their operations.
In France, mining for uranium ore ceased in 2001 when the economically recoverable deposits were depleted.
Uranium was mined at 210 sites in France scattered all over the country. Although fewer than half of these sites were operated by AREVA and its subsidiaries, the group is providing a public service by redeveloping and monitoring all of the sites, in accordance with its agreement with the French government.
Reclamation of depleted mining sites
Once all the ore has been removed, mining sites are cleaned, reclaimed and planted in compliance with environmental regulations. To date AREVA has spent over 400 million euros to carry out these redevelopment operations for 13 sites in France, Gabon, the United States and Canada.
Mine redevelopment is an industrial operation in its own right and is conducted on solid scientific and technical grounds. Through consensus building and adherence to regulations, site rehabilitation seeks to:
- Ensure public health and safety.
- Minimize the impacts of residual legacy operations.
- Limit the use of space by legacy sites.
- Ensure that they harmonize with the landscape.
These operations are conducted in complete transparency. They are supervised by the departments of the ministries of research, industry and the environment (DRIRE) as well as by the nuclear safety authority (ASN) and the department of health and social affairs (DASS). Organizations for consensus building and analysis (CLIS local information and monitoring commissions, pluralistic study groups) were also created to respond to the expectations and questions of the different stakeholders.
The redevelopment of mine sites requires real know-how, which is why a single operator is usually chosen. The French government chose AREVA for this mission, including the redevelopment of sites that the company did not operate, due to its recognized expertise in natural uranium and its commitment to social responsibility. With a rehabilitation budget of 4 to 5 million Euros per year, AREVA continuously has 100 specialists in health, radiation protection, geology and the environment working on this subject and performs close to 10,000 analyses every year.
More on Rehabilitating mine sites
The Ecarpière site
Mine site redevelopment: the Écarpière site operates a solar energy park
Having once produced uranium, the Ecarpière site near Nantes, France is about to get a second life.
Solar panels will be installed over a 12 hectare area (30 acres) to generate electricity.
The project is set to be launched in late 2009. Managed by AREVA, the project is in perfect alignment with the directives of the "Grenelle de l'environnement" Environment Round Table: by 2020, 23% of the electricity generated in France will originate from renewable energies.
The solar panels will be placed 1.5 meters from the ground, capturing solar energy to generate electricity.
This photovoltaic plant could start generating power in the last quarter of 2009. Each year around 5,000 MWh will strengthen the power grid from this site. That's enough to supply energy to a small town of 3500 inhabitants.
From uranium to solar energy, in just one step. Other similar projects are being planned in places such as the Hérault department and the Forez area (France).
The Limousin GEP: a real answer to societal expectations following the end of uranium mining operations in France
Created by the French ministries of the Environment, Health and Industry on June 28, 2006, GEP (the Pluralistic Expertise Group) is working on assessing and dealing with the radiological footprint of legacy uranium mines operated by AREVA NC (COGEMA) in the Limousin region in decades past.
With support from the institute of radiation protection and nuclear safety, or IRSN, the GEP was tasked with performing a critical review of technical documentation supplied by the mining operator and making recommendations for reducing site impacts on members of the public.
The GEP at a glance
Its creation was strongly advocated and supported by AREVA.
- 3 years of study: 2006 -2009.
- 24 sites in the Haute Vienne department studied (the largest).
- An initiative whose recommendations are awaited with interest by all communities and DRIREs affected by uranium mining operations.
- 40 members from some fifteen groups of scientific experts (CNRS Nancy, University of Limoges, INVS, IRSN) and associations (Wise, GSIEN, Sources and Rivières du Limousin).
- 5 nationalities (British, Belgian, Swiss, French and Luxembourgers).
- 4 task forces in 4 major study areas:
- Source term studies (site hydrogeology and geochemistry).
- Dosimetry, exposure scenarios, health, study of cancer records (initial findings: the number of cancers in the Limousin region is lower than the national average).
- Changes to regulations in step with growing knowledge.
- Interpretations of measurements; concept of representativeness of environmental samples.
Exposure to radioactivity
Natural radioactivity and artificial radioactivity
Radioactivity is a natural phenomenon. It is caused by the ability of the nuclei of atoms of some radioactive bodies to transform spontaneously into other atoms (radioactive or otherwise) while releasing energy-carrying radiation.
It is found in:
- The ground and in earthen materials (terrestrial radiation).
- From the sun (cosmic radiation).
- And even in the human body (potassium-40, carbon-14).
Humans have learned how to produce radioactivity artificially for the requirements of medicine and industry. Whether natural or artificial, the characteristics and effects of the radioactivity are identical. In France, 70% of the radioactivity to which a person is exposed is of natural origin, while 30% comes from "artificial" radioactivity, mainly from medical uses. The average annual dose to an individual from natural sources is 2.4 mSv; total exposure is about 3.3 mSv.
Some examples of radiation exposure for an individual
Average annual exposure:
- A cosmonaut in orbit: 420 mSv.
- Natural exposure in village of Ramsar, Iran: 300 mSv.
- Natural exposure in an unventilated house in a granite region: 20 mSv.
- Natural exposure at an altitude of 1,500m: 3.6 mSv.
- Natural exposure of an individual in France: 2.4 mSv.
- Aftermath of atmospheric nuclear testing: 0.017 mSv.
- Waste from nuclear plants: 0.002 mSv.
- Abdominal scanner: 12 mSv.
- Lung radiography: 0.1 mSv.
- Paris-New York flight: 0.06 mSv.
- Panoramic dental x-ray: 0.03 mSv.
Exposure to radioactivity
- Remote: the radiation is emitted by a compound located more or less far away from the human body. This is known as irradiation or external exposure.
- By absorption: the radioactive product is absorbed by the respiratory or digestive tracts or through the skin (via open sores, for example), and the radiation is emitted directly to the cells. This phenomenon is known as internal exposure or contamination.
- By contact: radioactive particles can be disseminated on clothing or on the body (hair, nails, skin) without penetrating the body. This is external contamination.
Biological effects of radioactivity on humans
- Deterministic effects: at high doses received instantaneously, radioactivity induces observable effects almost immediately. These effects are expressed as a dose threshold equal to or greater than 500 mSv (burns, nausea, death of exposed organs).
- Random effects: below 500 mSv, there is no observable effect over the short term. However, effects may appear later, several years after the exposure, but not systematically (mainly cancers).
The biological effects of radiation are identical at identical doses, regardless of whether the source is natural or artificial.
- Mine tailings: earth, sand or rock that does not contain ore but that must be extracted to gain access to the ore itself. Very little or no radioactivity.
- Mining residue: part of the finely milled ore that contains little, if any, uranium as a result of the separation of the uranium from the rock in the ore treatment plan (production of uranium concentrates). The tailings are in the form of very fine sand and still contain 70% of the initial radioactivity (natural radioactive elements associated with the uranium in the ore: lead, bismuth, polonium, radium, radon, etc.). They are disposed of near the processing plants. Their disposal and monitoring represents a very large share of rehabilitation and monitoring operations.
- (CLIS): Commission Locale d'Information et de Surveillance, the local information and monitoring commission in which all elements of civil society - associations, elected representatives, administrations - are present.
- GEP: Pluralistic expertise group.
- DRIRE: regional departments representing the ministries of Industry, Research and the Environment.
- ASN: The French nuclear safety authority.
- DASS: French department of health and social affairs.
- ALARA: "As Low As Reasonably Achievable."
- IRSN: Institut de Radioprotection et de Sûreté Nucléaire.
- ICPE: French institute of radiation protection and nuclear safety.