State-of-the-art and challenges of non-destructive techniques for in-situ radiological characterization of nuclear facilities to be dismantled

[EN]This paper reports on the state-of-the-art of the main non-destructive assay (NDA) techniques usually used for in-situ radiological characterization of nuclear facilities subject to a decommissioning programme. For the sake of clarity and coherence, they have been classified as environmental radiation monitoring, surface contamination measurements, gamma spectrometry, passive neutron counting and radiation cameras. Particular mention is also made here to the various challenges that each of these techniques must currently overcome, together with the formulation of some proposals for a potential evolution in the future.This study has been funded by the European INSIDER project, through the Euratom Research and Training Programme 2014-2018, under grant agreement No 755554

Uncertainty and detection limits of Pu-241 determination by liquid scintillation counting (LSC)

[EN]Determination of Pu-241 is an essential issue for radiation protection, as it is the precursor of some nuclides with high radiotoxicity. Pu-241 is a low energy beta emitter, which makes its measurement more challenging than that of Pu alpha emitters. The most widely used method for the measurement of Pu-241 is liquid scintillation counting (LSC). In this method, the assessment of Pu radiochemical yield is done by measuring the sample by alpha spectrometry before being lixiviated and measured by LSC. This double measurement affects uncertainty analysis, as well as decision threshold and detection limit, considering that both components of the total yield (radiochemical and lixiviation) should be contemplated. In this paper, and for quality assurance (QA) purposes, in-depth uncertainty and detection limit formulae for the proposed method, controlling correlations and considering all the parameters involved including chemical and lixiviation yields, have been developed. A sensitivity analysis of the uncertainty budget together with an assessment of Pu-242 tracer quantity to be used, ensuring a total yield of at least 50% and a relative uncertainty of the leaching yield of at most 5%, have been carried out. In addition, an analysis of the impact of the real lixiviation yield value and its uncertainty on the results has been done. As a general conclusion, and considering the values of the parameters chosen for this work (samples of 1 g measured for 24 h by LSC), the Pu-241 uncertainties range from 5% to 30% depending on the activity concentration values and the detection limits range from 14 to 30 Bq kg(-1), depending on yield values. The main components of the uncertainty budget are the net Pu-241 and background counts obtained in the LSC measurement for low contaminated samples while this is the case for the alpha gross count rate in LSC measurement of the alpha calibration source for highly contaminated samples. In addition, an analysis of possible interference by Pu alpha emitters in the Pu-241 signal and a comparison of quench standard curves of H-3 and Pu-241 are also performed.Open Access funding provided by University of the Basque Country UPV/EHU

Recommendations for the selection of in situ measurement techniques for radiological characterization in nuclear/radiological installations under decommissioning and dismantling processes

[EN] In this paper, in-situ radiological characterisation by means of non-destructive techniques is studied and analysed in the context of the different constrained environments (identified as radioactivity, materials, accessibility and other hazards) that may be encountered in the nuclear facilities undergoing decommissioning and dismantling. As a complement to a previous paper (Aspe et al., 2020), the present one gives a global guidance to assist with the decision making process regarding the selection of in-situ measurement techniques that could be applied in such constrained environments. In addition, from the definition of the investigation objectives, and for each one of the most common in-situ measurement techniques, a brief description is given about the impact of the above constraints and how to integrate them onto the system definition, including the experimental design, the mechanical integration and the data management, to properly define the best radiological characterization methodology. Moreover, complementing this general view, all the phases – from initial to final – of a D&D programme were taken into account to provide basic recommendations, together with some particular dispositions, for the appropriate implementation of the chosen instruments. Strengths and weaknesses of the common detectors used for the different in-situ measurement techniques, as well as their recommended applications in nuclear facilities are also outlined.The research leading to these results has been carried out in the framework of the European INSIDER project and has received funding from the Euratom Research and Training Programme 2014–2018 under grant agreement no. 755554

Analysis of the comparison of in situ measurements made on biological shielding of the BR3 nuclear reactor

INSIDER (Improved Nuclear SIte characterization for waste minimization in D&D operations under constrained EnviRonment) was a European project funded under the H2020-EURATOM programme and launched in June 2017. The project was coordinated by the French Commissariat a l'energie atomique et aux energies alternatives (CEA), it had a total duration of 4 years and covered a budget of 4 Meuro. INSIDER's work was performed by 5 technical working groups (WG) which brought together 18 institutions from 10 countries, leading to a total of 68 participating researchers. The objective of the project was to optimise the radiological characterisation of nuclear installations in constrained environments in order to obtain an accurate estimate of the content of contaminated materials as well as to optimise the quantity of contaminated materials to be treated as waste. The focus of this paper is on the statistical analysis of an interteam comparison of measurement results (dose rate, total gamma measurement, and gamma spectrometry) made in situ at the BR3 reactor, Belgium.The authors would like to thank the participants in the comparison: Fernando Legarda and Raquel Idoeta from Basque Country University (UPV/EHU Spain), Jesús Ruiz from TECNATOM (Spain), SCK-CEN (Belgium), Peter Volgyesi from MTA-EK (Hun- garia), Polina Otiougova from PSI (Switzerland), Lousai Leong from MIRION (France), Axel Klix from KIT (Germany)

Multiple nodal locoregional recurrence of pheochromocytoma

AbstractIntroductionMalignancy is present in 10% of pheochromocytomas (PCC) and is defined as local/vascular infiltration of surrounding tissues or the presence of chromaffin cells deposits in distant organs. The presence of isolated nodal recurrence is very rare and only 7 cases have been reported in the medical literature.Presentation of the caseThe case of a 32-y male with a symptomatic recurrence of a previously operated (2-years ago) PCC is presented. Radiological and functional imaging studies confirmed the presence of multiple nodules in the surgical site. A radical left nephrectomy with extensive lymphatic clearance in order to get an R0 resection was performed. The pathologist confirmed the diagnosis of massive locoregional nodal invasion.DiscussionA detailed histological report and a thorough genetic study must be considered in every operated PCC in order to identify mutations and profiles of risk for malignancy. When recurrence or metastastic disease is suspected, imaging and functional exams are done in order to obtain a proper staging. Radical surgery for the metastatic disease is the only treatment that may provide prolonged survival. If an R0 resection is not possible, then a debulking surgery is a good option when the benefit/risk ratio is acceptable.ConclusionIsolated lymph nodal recurrence is very rare in malignant PCC, with only 7 cases previously published. The role of surgery is essential to get long-term survival because provides clinical and functional control of the disease

Possibilities of the use of CeBr3 scintillation detectors for the measurement of the content of radionuclides in samples for environmental monitoring

The investigation of radioactivity in samples is an application of gamma-ray spectrometry dealing with low and very low level gamma-ray activities of different isotopes. Gamma-ray spectrometry performed in the framework of radiological environmental monitoring may be done after selective sampling processes or after a chemical purification of a sample. Both cases imply that only some specific radionuclides should contribute to the obtained spectrum. Gamma-ray spectrometry performed with medium energy resolution detectors may allow the possible distinction of their photopeaks. Therefore, a cerium bromide (CeBr3) detector can be particularly attractive for routine tasks in radiological environmental monitoring as it has a high efficiency, medium energy resolution and it can work at room temperature. This study describes the conditions under which a CeBr3 detector can serve for some routine analysis in radiological analysis of samples collected in the environment or collected by airsamplers in environmental radiological monitoring programmes

Selectivity analysis of 99Tc determination by LSC in the field of nuclear decommissioning

In this work, two Tc radiochemical isolation methods—a conventional method by Triskem TEVA ® resin and a rapid method by Empore™ Tc Rad Disk—are compared in the field of nuclear decommissioning and 99Tc assessment. The conventional method results more selective than the rapid one, being able to remove almost 100% of the main radiological interferers with the exception of the 90Y; however, the rapid method obtains higher chemical yields (97% vs. 80%) and slightly lower detection limits (0.025 Bq vs. 0.030 Bq) than the conventional. Both methods are similar with regards to equipment and reagent costs.We would like to acknowledge the Open Access funding provided by the University of the Basque Country UPV/EHU

Balanced ScoreCard Y las Normas de Integración PAS 99:2006

Para el desarrollo de este trabajo se utilizaron las recomendaciones de Norton & Kaplan para la implementación del Balanced Scorecard (BSC), además herramientas novedosas de diagnóstico como SISTRAT, el software para mapas estratégicos DC Map.xls y LINUX UBUNTU para el desarrollo del Cuadro de Mando. Una vez implementado el BSC se hizo un estudio longitudinal de datos en el Cuadro de Mando, se analizó en qué medida la aplicación del BSC en la Empresa de Diseño e Ingeniería (EDIN) tenía coincidencia con los siete principios de las normas de integración PAS 99:2006. Para esta comparación se utilizó como herramienta de medición las Distancias Relativas de Hamming en su perfil ideal. En la medida que las distancias relativas fueron disminuyendo se realizaron los análisis respectivos que demostraron que el BSC implementado en EDIN era compatible con PAS 99:2006.Palabras clave: Sistemas Integrados de Gestión, Cuadro de Mando Integral, Distancias Relativas de Hammin

Radiological environmental monitoring of groundwater around NPP: A proposal for its assessment

Whether a nuclear installation has radiological impact and, in that case, its extension, are the questions behind any environmental analysis of the installation along its operational life. This analysis is based on the detailed establishment of the radiological background of the area. Accordingly, the dismantling and decommissioning process (D&D) of a nuclear power plant starts with a radiological monitoring plan, which includes the radiological characterization of the area and of its surroundings. At the completion of the D&D, unrestricted use for the site will be permitted strictly in accordance with results of the radiological survey within the limits established by the local authorities. Groundwater quality is typically included in any radiological analysis since, among other reasons, a significant part of it is highly likely to end up being extracted for domestic use and hence, human consumption. While there is no regulation containing maximum activity concentration or radionuclide guidance values for water that may be destined for uses other than public consumption, if groundwater is considered a “part” of the land, dose criteria for site release can be applied. Therefore, together with the guidance levels to be established for the different radionuclides expected in the groundwater, the detection limits to be employed when performing routine radio analytical characterization procedures in the laboratory should also be provided. In this paper, we first propose a relation of the potential radionuclides to be analyzed in groundwater, together with their detection limits to be achieved when the determinations are performed in a laboratory, and subsequently, we discuss the most suitable analytical methodologies and resources that would be necessary to undertake radiological characterization plans from a practical point of view

The 2019-2023 Strategic Plan of the Spanish Society of Radiological Protection (SEPR)

The Spanish Society for Radiological Protection (SEPR) is a scientific and technical organization that aims to bring together all radioprotection professionals from all the sectors of activity where ionizing and non-ionizing radiation is produced. The development of the SEPR's Strategic Plan every 5 years is the cornerstone of all the different activities that the Society carries out. This document establishes the SEPR goals and objectives for that period, as well as the activities planned to achieve them. It is a living and open document that draws on past experiences while looking to the future. The Strategic Plan 2019–2023, approved on June 2019, is the Third Strategic Plan of the SEPR. In its preparation, account has been taken of the experience obtained in the application of the two previous Strategic Plans, as well as of the new demands of the general public and of professionals in the area of radiological protection that have become apparent during the previous period. This paper describes the development of the current Strategic Plan, as well as the Plan itself, and briefly analyzes its implementation in the Conclusion.Peer ReviewedPostprint (published version