In France, the mining and milling of uranium ore and the disposal of uranium mill tailings involved nearly 200 sites of very different nature. Being in charge of both the review of some remediation reports and the routine monitoring of the environment provides IRSN with selective data on most sites. The data collected by IRSN as well as those available from other data sources often remain incomplete therefore preventing IRSN from presenting a global view or answering some specific questions. In order to overcome this difficulty, it was decided, under the aegis of the Ministry of Ecology and Sustainable Development, that IRSN should develop a program of investigations organized in two parts: Part 1, called “State of knowledge" is aimed at assessing the amount of information available and at consolidating it into a user-friendly computerized database. The main goal is to identify the occurrence of significant enhanced radiological levels in the environment and to detect any lack of information concerning the various sites. This paper gives an overview of the information already collected. Part 2, called “specific studies" is aimed at fixing the gaps in the database by implementing new investigations on specific sites. It could lead to improvements in networks for the monitoring of radioactivity in the environment.

The present study is the second part of a program of characterization of the site surrounding the SoGIN Garigliano Nuclear Power Plant (Southern Italy), which is currently involved in decommissioning activities. In the first phase of the project the reference groups of the population were established on the basis of a socio-economical study of the site; the radiological doses due to the assumed radioactive releases during the decommissioning phase were calculated by using climatological, hydrological, geomorphological parameters of the studied area; transport and diffusion specific models of some radionuclides in the environment were implemented to calculate the dose using specific evaluation software. The second part of the study focuses on the project of an environmental network designed in order to ensure the continuous monitoring of the radioactive release concentrations. All the criteria for the choice of grid points, by considering specific paths of transfer in the environment, were established for all the environmental compartments. A field campaign was carried out aiming to assess the “zero level" due to the natural radioactivity and past anthropogenic activities.

Le détecteur solide de traces nucléaires CR39 a été utilisé pour déterminer le seuil de détection du bore. La réponse du détecteur CR39 a été établie grâce à des concentrations connues de boreobtenues par implantation ionique du 10B dans l'aluminium, et en variant les durées d'irradiations dans le canal thermique du réacteur nucléaire universitaire de Strasbourg. Il a été observé que ladensité des traces dans le CR39 est une fonction linéaire de la quantité de bore implanté et de la durée d'irradiation. Des considérations pratiques sur le comptage optique des traces conduisent àestimer un seuil de 1011 atomes cm-2 de 10B. Cette limite est d'un facteur mille inférieure à la quantité minimale requise par la boroneutrothérapie.

The research activities under the work package CAT2 – improvement of decision supportsystems, focused on the one hand to improve the operability of the RODOS system but on theother hand to enhance RODOS and ARGOS with simulation models still missing in theportfolio of these two decision support systems. For RODOS, the work focused on theimprovement of the atmospheric dispersion modelling in complex terrain and the improvementof the data assimilation functionalities. For both systems, the later phase models dealingwith countermeasures in inhabited areas and food production systems have been considerablyenhanced.

An accurate model of atmospheric dispersion of radionuclides over the complex terrain of La Hague reprocessing plant (North Cotentin, France) has been developed by COGEMA, in partnership with Paris VI University, and has been yet adapted for an other industrial site (Marcoule). This model, called CEDRAT, takes into account areas typically outside the validity range of Gaussian models: topography and building influence, short-distance (beyond 500 m from the release point) and various atmospheric stability conditions. CEDRAT allows to reach an effective compromise between rapidity (30 min on a 6000 nodes grid, on a standard PC), robustness and accuracy, coupled with a user-friendly interface. The validation process consisted first of a comparison with the 3D reference model MERCURE, developed by EDF, and then, results of both models were compared on release scenarios thanks to tracer data (Krypton-85, an inert gas released from a height of 100 m) collected at five monitoring stations around the site. Then a second level of comparison, presented here, was made in collaboration with the IRSN Cherbourg Radioecological Laboratory, on ground and altitude (collected with a tethered balloon) field data.

COGEMA La Hague nuclear reprocessing plant is located in the North West of Cotentin peninsula near Cherbourg (France). This nuclear plant releases radioelements in atmosphere and in the English Channel. About 8.5 TBq.year-1 of radiocarbon are released as the liquid wastes through a pipe a few kilometres off sea shore, West of the reprocessing plant. Recent studies in the peninsula show anomalous higher radiocarbon contents in vegetation near the coast that have suggested a supplementary marine contribution through the degassing of the 14C excess supplied by liquid releases of the nuclear plant. Carbon dioxide partial pressure, 14C activities were measured in air and sea water in the Bay of Seine and around the COGEMA-La Hague nuclear reprocessing plant during three cruises in 2000 and 2002. Results show clearly that sea is a source of CO2 and 14C to the atmosphere. Higher 14C concentrations in air and water related to the La Hague liquid wastes are clearly recorded. The aim of this paper is to show results of these oceanographic campaigns. Flux between seawater and atmosphere are calculated in the North-West Cotentin and in Bay of Seine.

The dry deposition to several leafy vegetables (endive, head lettuce, red oak leaf lettuce, spinach) was studied. Particles with attached 134Cs were used for testing the particulate deposition, gaseous elemental 131I was the tracer for gas deposition. The particle deposition was the highest for rough and structured leafs as red oak leaf lettuce has, but as well for spinach with many open stomata. The stomatal uptake seamed to be the most important process for gas deposition, the deposition to spinach was for Radioiodine the highest as compared to all other species. The lowest deposition was always found to the closed heads of head lettuce. The difference in deposition to the various species was up to a factor 9.

The quantification of radionuclides by direct gamma-X spectrometry with energy below 100 keV requires knowledge the elementary composition of the sample or the development of a device for determining the mass attenuation coefficients. This is especially true for 129I which is characterised by a 29.8 keV X-ray and 39.6 keV gamma ray. Experimental equipment has been developed in order to obtain this mass attenuation coefficient as a function of energy. 129I concentrations were measured in samples of seaweed (Fucus serratus and Laminaria digitata) collected monthly over a period of one year nearby La Hague reprocessing plant in France. This paper describes the measurement methodology used to determine 129I concentrations and variations in the two seaweeds over a one-year period. Mean mass attenuation coefficients for 129I energies were established in order to determine the self-attenuation corrective factor for both seaweed species, regardless of the sampling date.

The general objective of the OSPAR radioactive substances strategy is to preventpollution of the maritime area from ionising radiation through progressive and substantialreductions of discharges, emissions and losses of radioactive substances, so thatconcentrations in the environment are close to background for naturally occurringradioactive substances and close to zero for artificial radioactive substances. The thirdperiodic evaluation of progress towards the objective of the OSPAR radioactive substancesstrategy concludes that, due to issues concerning the availability of reported data, it isnot possible to come to firm conclusions as to whether the aims of the OSPAR radioactivesubstances strategy are currently being delivered. However, in general there is anindication of a reduction in average marine concentrations of selected radionuclidesassociated with the nuclear industry, while doses arising from these selectedradionuclides in the OSPAR maritime area to humans are well within internationallyrecommended limits and are below the lowest levels at which any effects are likely tooccur for marine biota.

Le radon est un gaz radioactif dégagé par les sols et les matériaux contenant du radium. Une fois inhalé, il se dépose dans l'appareil respiratoire, où ses produits de filiation irradient les tissus,provoquant un risque de cancer. L'estimation de ce risque s'effectue à travers une approche épidémiologique ou dosimétrique. La première utilise les données sur la mortalité des mineurs ayantété exposés au radon. On extrapole ensuite les résultats à la population générale. Plus récemment, on a essayé d'estimer le risque directement à partir de la population générale. L'autre approcheessaie de calculer le taux de conversion entre la concentration de radon dans l'atmosphère ambiante et la dose absorbée par l'appareil respiratoire. On estime le risque de cancer à travers uncoefficient qui a été déduit des études sur les survivants de Hiroshima et Nagasaki. La gestion du risque comporte la définition de principes généraux et d'un ensemble de recommandations. Dansle passé, l'ICRP pensait qu'il ne fallait pas intervenir sur les risques provoqués par les irradiations naturelles. Depuis 1984, il a changé d'avis et a établi des limites d'acceptabilité en ce quiconcerne les concentrations de radon dans les habitations. Il faut relever que les estimations du risque de cancer sont entachées de marges d'incertitude relativement élevées. Les “ jugementsd'expert ” jouent un rôle important. Les “ jugements de valeur ” en revanche jouent un rôle fondamental en matière de gestion du risque. A l'évidence, il s'agit d'un problème ayant un caractèretransdisciplinaire et qui soulève la question du lien entre science et société.


Ce rapport fait la synthèse des calculs de radioprotection effectués pour l'ensemble du bâtiment abritant le cyclotron biomédical de Nice et les salles de traitement en proton et neutron, n n'a pas, bien entendu, la prétention d'évoquer tous les aspects de la sécurité et de la radioprotection autour des cyclotrons. Nous justifierons les épaisseurs des protections autour de la machine et des salles de traitement en indiquant les formules utilisées parmi les différentes méthodes décrites dans la littérature. Nous donnerons les caractéristiques des labyrinthes d'accès aux salles de traitement qui remplacent les lourdes portes trop traumatisantes pour les malades et délicates d'utilisation en fonctionnement médical. Nous discuterons de l'activation de l'air due essentiellement aux réactions des neutrons avec les différents éléments qui le constituent et de la nécessité d'une ventilation dans les salles de traitement, la voie de faisceau et le hall du cyclotron.

Pour le projet EPR (European Pressurized Reactor) de Flamanville, EDF a décidé de prendre en compte la radioprotection dès la phase de conception, au même titre que la sûreté. L’approche pour traiter les activités à forts enjeux radioprotection a été d’intégrer tous les acteurs, concepteurs, exploitant, entreprises intervenantes lors de 3 étapes successives, d’abord une enquête auprès des intervenants et concepteurs, puis l’étude des propositions, enfin la phase décisionnelle au sein d’un comité ALARA. L’objectif radioprotection qu’EDF s’est fixé pour ce nouveau réacteur est de se situer dans une démarche de progrès continu et d’optimisation en comparaison aux meilleures tranches du parc avec un objectif fixé actuellement en dose collective à 0,35 H Sv/an et par tranche. Le travail porte entre autre sur une démarche d’optimisation des travaux les plus exposants avec un nouvel enjeu des interventions dans le bâtiment réacteur, tranche en fonctionnement, et ceci pour améliorer la disponibilité de la tranche. Il est envisagé d’intervenir 7 jours avant l’arrêt du réacteur et 3 jours après, ceci pour préparer la logistique des interventions à venir. L’estimation de la perte sans optimisation est actuellement de 4,5 % sur la dose annuelle. Pour cela, deux zones dans le bâtiment réacteur de l’EPR ont été créées, une zone inaccessible chargée de collecter les fuites du circuit primaire et une zone accessible tranche en fonctionnement, séparée de la zone accessible par des moyens de ventilation et installation adaptés. Pour se protéger des flux de rayonnements (neutrons et γ de haute énergie), les études de radioprotection ont conduit à la mise en place d’un plancher béton, de protections neutroniques à la sortie des tuyauteries primaires et au renforcement des casemates GV et des pompes. L’ensemble de ces dispositions conduira à ce que la zone accessible soit classée zone verte (débit de dose inférieur à 25 µSv/h) avec un débit de dose neutrons inférieur à 2,5 µSv/h. Pour améliorer la dosimétrie au sein de l’EPR, le travail a porté sur deux paramètres intervenant dans le calcul de dose : le débit de dose et le volume de travail exposé. Les principales évolutions de conception dans le domaine de la radioprotection ont été réalisées par rapport au dernier palier existant, le palier N4. Pour garantir la propreté radiologique, il est nécessaire de confiner la contamination au plus près de la source sur les tranches en exploitation. Les objectifs de ce type de zonage sont essentiellement de permettre à l’exploitant de produire des déchets conventionnels issus de zone contrôlée pour diminuer la quantité de déchets nucléaires produits, de permettre lors du démantèlement de diminuer les volumes de déchets nucléaires et de réduire les zones où il existe un risque de contamination et limiter ainsi tout transfert de contamination à l'extérieur des installations. Au total, cette démarche d’optimisation a permis d’estimer un gain de 21 % entre la dose de référence et la dose optimisée EPR. La radioprotection, enjeu stratégique de l’entreprise EDF, sort peu à peu du cercle restreint des experts et devient un domaine transverse où le travail en équipe pluridisciplinaire prime dès la phase de conception.

In the present work, external annual radiation doses in human body due to presence of 226Ra, 232Th, 238U and 40K in conventional building materials and by-products from coal power plants which are being used or have the potential for use in buildings and soil in India were calculated in the human body by using GENII radiation dose calculation computer programme (Napier et al., 1988). In the calculations, human beings receive the most radiation dose from building materials from 1.0 × 10-6 Sv from 40K and the least from 2.3 × 10-11 Sv from 232Th. It has been calculated that human beings receive total 6.3 × 10$^{-7} \pm$ 2 × 10-7 Sv radiation dose exposure from soil. Data obtained are acceptable in comparison with radiation doses attributable to building materials in OECD countries.

Quaternary sediments and soils at the Forsmark site (Sweden) would constitute the last barrier for radionuclide migration interposed between a deep repository of high level nuclear wastes (HLNW) and surface ecological systems. The retention capacity of these sediments is evaluated by means of reactive transport simulations. Two different scenarios have been modelled: (1) Inflow of deep fluids carrying radionuclides into shallow aquifers hosted in the carbonate glacial till, and (2) Inflow of deep fluids carrying radionuclides into organic matter-bearing clays. The model results predict that caesium is very efficiently retained in both scenarios for periods longer than 3000 years due to the strong affinity of this ion with the frayed edge sites of the illite layers. Strontium is also retained via cation exchange in illite and, in a lesser extent, via co-precipitation in calcite. The retention efficiency for strontium, however, quickly decreases to 0 after 1000 years. Uranium is retained in both scenarios with retention efficiencies higher than 40% at long term (>3000 years) due to precipitation of amorphous uraninite and adsorption on Fe(III) oxyhydroxides. Radium is only retained in the till aquifer since co-precipitation with barium sulphate does not occur in the clay porewater.

The EXTREME project was launched by the IRSN in 2005 to study the consequences of extreme meteo climatic events on reuptake of stocks and associated fluxes within the various compartments of the geosphere. Large masses of matter transferred during such events are liable to be displaced between locations, leading to higher pollution levels than those arising from average transfer processes, and producing pollutant fluxes that can be equivalent to the fluxes accumulated over several months or even years. This particularly concerns particle-reactive contaminants such as trace metals and long lived artificial radionuclides. The final aim of the project is to estimate the vulnerability of a coastal system (the Gulf of Lions, north western Mediterranean sea) to global change over the next 30 years. Indeed several programs dedicated to climate change predict a potential increase in the frequency of extreme events such as floods, floodings, saharian dust episodes, forest fire events and storms, particularly within the studied area.

With the ICRP recommendations Publications 103, 109 and 111 (ICRP, 2007; ICRP 2009a,2009b), new concepts and quantities have been introduced into emergency management andrehabilitation. Two of them will possibly influence national procedures, but for sure theywill influence countermeasure simulation approaches: 1. The concept of a “reference level”for emergency and existing controllable exposure situations that represents the level ofdose or risk, above which it is judged to be inappropriate to plan to allow exposures tooccur, and for which therefore protective actions should be planned in advance. 2. Whendeciding on the optimum course of protective actions, all exposure pathways and allrelevant actions have to be taken into account. The major changes for the simulationmodels result from the second recommendation that all exposure pathways must be consideredwhen deciding on protective actions. So far all countermeasure simulations in the earlyphase of an emergency are carried out by considering individual countermeasures such assheltering or evacuation, if some dose limit for the respective action is exceeded. Thisapproach has to be changed and strategies of several countermeasures analysed andsimulated with the ultimate goal not to exceed the reference level over a given timeperiod, typically one year.

The unusually strong earthquake in Japan on 11 March 2011 and the following extremetsunami caused enormous damage in the buildings of Fukushima Dai-ichi Nuclear Power Plant(NPP) situated on the Pacific coastline of Japan. The accident led to the release of alarge amount of radioactive material into the environment. According to the measurementsof the Radiological Monitoring and Data Acquisitions Network (RAMDAN) the radioactiveplume reached Hungary on 24 March 2011. The main volatile fission products –131I, 134Cs, and 137Cs radioisotopes – were measurable in aerosoland fallout samples in Hungary. Their activity concentration in air reached the maximumvalue in the last days of March and returned to the background level in the first half ofMay. As a consequence of respiration of contaminated air, a maximum of 1 Bq per capita of131I could be accumulated in the thyroid gland of the Hungarian population during thegiven period. The calculated upper limits of the committed effective dose from inhalationof 131I were 4 nSv and 10 nSv to the Hungarian adults and infants,respectively. These values are a hundred thousand times less than the annual radiationdose from natural sources to the Hungarian population. The radiation dose from radioactivecaesium isotopes originating from Fukushima was even less, around 1 nSv on average, toHungarian residents. No health deterioration can be expected from this radiationburden.