[en] The aim of this work is based on the use of interelemental correction coefficients which are calculated through fundamental parameters. To this purpose, it is necessary to know about the physical constants for each element including the absorption coefficient values and fluorescence yield, the incidence radiation energy, geometric and instrumental parameters. Besides, a special application of the program for the determination of a Nd-La mixed crystal formula is included. (Author)

[en] This work is focussed on characterization, organization and analysis for the most relevant regional parameters used in dose assessment models when a food pathway contamination occurs. It was carried in the framework of a contract with a several European Institutions (CEA-IPSN, NRPB) for the development of a general methodology for the evaluation of the radiological consequences caused by accidentally radioactive releases into the environment. Spain, a member of the mediterranean country group, has a remarkably diverse climate which determines crop production agricultural practices, and consequently the animal and human diets. This project intention in to study in depth these particular characteristics and their consequences so that the estimated dose received by an individual reflects a variety of factors, therefore, the production and consumption of the five autonomous Mediterranean regions have been compared individually and globally with the national production and consumption averages. These data have been used in committed dose evaluation exercise applied to the ingestion of contaminated food throughout the first year after an accidental release of Caesium-137. This exercise was realized within the TARRAS (Transfer of Accidentally Released of Radionuclides in Agricultural Systems) project, financed by CE, ENRESA and CSN. (Author) 6 ref

[en] Short communication

[en] The metabolic behaviour of inhaled uranium is studied. Using a particular analytical method applied to the models and dose assessment methods recommended by ICRP, the organ committed equivalent dose and effective equivalent dose are calculated. The exact ALI and DAC are derived from there. In the paper, the influence that various parameters have on those results are considered for the specific case of a particular nuclear element fabrication factory. Different AMAD and solubility type of inhaled material are specially analyzed. The results show the paramount importance of some of these parameters on the secondary and derived dose limits. Relationships between the real intake, as a fraction of ALI, and the lung retention or urine excretion are shown for different cases and intake forms hypothesis. Minimum detectable intakes with the available experimental techniques are then established. The results shown in the papel are a useful tool to help on the decision on the type and frequency of the individual monitoring techniques to be established in different circumstances. (Author)

[en] This work constitutes an approach to defining methodologies to deal with environmental recovery after an accident. This is a complex issue which has neither been conceptually nor functionally solved. This report summarizes the developments of the operating research projects of the Radiological Protection Programme for Intervention at CIEMAT

[en] Following an accident with environmental consequences, intervention may be necessary. The type of remedial actions and the strategy required will be dependent upon, inter alia, the phase and conditions within the contaminated scenario. Leaving aside the basic countermeasures (such as confinement, evacuation), which are based on internationally agreed Generic Intervention Levels (GIL's), the paper deals with intervention strategies leading to a return of the contaminated site to as close to normality as possible with the lowest social cost. The reduction of the damage from the existing contamination must be justified and optimised; the best strategy for applying recovery actions must be selected from a set of potential alternatives. A methodology for intervention strategies analysis, developed in the framework of CEC-CHECIR ECP-4 'Decontamination Strategies', is presented together with some examples of application. (author)

[en] This paper is framed in the field of radiological protection dealing with so called de facto situations. Therefore, it aims at situations where the radiological risk can only be reduced by some type of intervention. Specifically, the paper focusses on the aspects involved in environmental restoration of contaminated areas as a consequence of nuclear accidents. After describing the methodology and criteria used in analysing the intervention strategy, the computer model which implements the methodology and its main components are also described. Finally, a case study from the Chernobyl scenario is shown as an example where the proposed methodology can be applied. (Author) 8 refs

[en] The applicability study of the best countermeasures for the restoration of environments contaminated by the accidental liberation of radionuclides, requires the assessment of the space and the temporal flow of radionuclides. The objective of the multinational project TEMAS (Techniques and Management Strategies for environmental restoration and their ecological consequences), that is carried out under EU-CIEMAT contract n. TI4-CT95-0021, is the development of management tool that provides the necessary support in the selection of the best strategies of environmental restoration after a nuclear accident, considering all the possible affected environments (urban, agricultural, semi natural and forest). In the forest environment,CIEMAT is working with the University of Lund (Sweden) and the Physical Science Faculty of the University of Seville in the prognosis of the distribution of Cesium and Strontium in forest ecosystems and through the associated production systems. This paper summarizes the study of the response of two different models, FORM and FORESTPATH to predict the radionuclides flow in the event of an accidental contamination of a forest. The comparison of results has been carried out over a period of 100 years after deposition on a coniferous forest. Although the approaches are different, the results obtained (using generic parameters) indicate that either model could to be selected for the analysis of the intervention in TEMAS. (Author) 14 refs

[en] TEMAS (Techniques and Management Strategies for Environmental Restoration) is a user friendly decision aiding computerised system to help in th e selection of the best local strategy of restoration when a post-accidental environmental contamination with long lived radionuclides (''137 Cs, ''134 Cs and ''90 Sr) must be faced. TEMAS provides answer for complex scenarios (urban, agricultural and forest) with different specific levels of contamination, uses and dimensions. The computerized system is structured in three main modules: Databases containing those parameters required to identify and to provide results for typical potential cases of intervention (elemental cases); the evaluation module that uses a limited number of inputs to compose a virtual representation of the real contaminated scenario, in terms of elemental cases, and then calculates the required decision factors (residual individual doses, averted collective doses, costs and other secondary effects after each applicable intervention options); and the decision module which manages these factors according to a certain criteria to select and rank interventions as the recommended strategy. This document describes the contain of the databases, the main calculations of the different procedures and its correlation with databases, schematic draws of the fluxes of calculations, and one simulation of intervention to exemplify inputs and outputs of the system. (Author)

[en] Full text: A conceptual decision system implemented as help decision tool that can contribute to the management and rehabilitation of contaminated areas is presented. The first version of the tool was developed in the TEMAS PROJECT. The TEMAS project (Techniques and Management Strategies for Environmental Restoration and Their Ecological Consequences), was assembled into an Association Contract (FI4PCT95-0021 with the European Atomic Energy Community in the frame of 4^oFP of the UE, and whose objectives were concentrated on the development of techniques and management strategies for environmental remediation after contamination of landscapes or sites with radioactive substances. The main result of the project was the development of a user-friendly decision-aiding computerized system (TEMAS DSS) able to select the best local strategy of restoration when a post-accidental environmental contamination with long lived radionuclides (caesium and strontium) must be faced. TEMAS provides answer for complex scenarios including urban, agricultural and forest ecosystems in the frame of the European Community with different levels of contamination, uses and dimensions. The TEMAS system is organized in two modules, the first to evaluate the radiological impact from the scenario on the affected population, the second to decide the best strategy to control the risk sources. The evaluation methodology breaks down the contaminated scenario into a set of elemental units for restoration taken into account the applicability of the intervention options in terms of practicability, radiological efficiency, cost and secondary effects. Each unit is considered as an individual source of risk and is associated to different applicable countermeasures. Radiecological models describing fluxes of radioactivity from each elemental unit through its associated pathways (e.g. soil, plant, animals to consumption products) and dose models evaluating radiological impact to the population from external exposure and ingestion are used. For each potential intervention in the elemental unit, a set of decision factors including costs, contribution to the individual dose to six age groups and averted collective dose are calculated. The decision model was based on the basic principles of radiological protection in force when the project was being developed: to guarantee that unacceptable levels of individual dose are never reached; to reduce the collective risk in an optimized way with regard to the social cost associated to the intervention. According such principle, three bands of action are identified in TEMAS to decide if the intervention should be mandatory, considered as option or discarded on the basis or the radiological risk involved. In the two first cases, TEMAS offers a set of applicable countermeasures ranked in terms of cost effectiveness (cost of the unit of collective dose averted). At present the ICRP is putting more emphasis in the control of the radiological risk using the levels of individual doses to be compared to action levels and supporting the optimization an doses to affected groups and other consequences evidenced by stakeholders. TEMAS is being adapted to this new perspective. Once concluded the prognosis of the required initial actions in the early phase of a emergency, a common output of all emergency management systems is the residual scenario of deposition. TEMAS can use this information to predict the relative contribution to the individual dose coming from each contaminated unit without and alter applying different options of intervention. The present contribution deals with the updating of TEMAS to the new ideas for the control of radiation sources in case of prolonged exposure. The predicted annual individual doses in the evaluation module for each elemental unit for restoration is compared to reference or protective action levels to decide if reduction of doses must or not be considered. The principle of the optimization when intervention is required can be applied for each elemental unit because TEMAS provides unfolded contributions. TEMAS links the levels expressed as incremental individual dose to measurable quantities such as concentrations of activity in soils or products. In this way TEMAS can help obtain derived reference levels in terms of concentration of activities for a given scenario. A case study for the restoration of a complex scenario comparing the results from use of both approaches for the decision is presented. (author)