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[en] Comparing the costs of different power generation technologies has become one of the main arguments used by proponents of specific sources and those seeking to find the best approach to plan the expansion of electrical systems. However, this approach, taken alone for public energy policy making, is far from simple and can lead to unwanted and unexpected results. How much does it cost? It seems like a simple question. However, when it comes to competing power generation technologies, it is an extremely challenging question. Generation costs include many variables: capital, fuel, location, waste disposal, environmental impact, interconnection, reliability, intermittency, and other external and systemic costs. No two technologies are alike. System costs are often divided into the following four broadly defined categories of profile costs (also referred to as utilization costs or backup costs), balancing costs, grid costs and connection costs: – Profile costs refer to the increase in the generation cost of the overall electricity system in response to the variability of VRE output. – Balancing costs refer to the increasing requirements for ensuring the system stability due to the uncertainty in the power generation (unforeseen plant outages or forecasting errors of generation). – Grid costs reflect the increase in the costs for transmission and distribution due to the distributed nature and locational constraint of VRE generation plants. – Connection costs consist of the costs of connecting a power plant to the nearest connecting point of the transmission grid.
[en] For more than 30 years, the IRSN Barometer has been following annually the perception of risks and security by the French people. This continuous study provides precious insight to better understand risk perception, which in turn helps IRSN better handle risk assessment. The Barometer focuses on four major topics: 1) the current concerns of the French, 2) their views on science and expertise, 3) their perception of various risk situations, 4) their opinion on nuclear matters. This year, for the fourth consecutive year, it also displays four viewpoints from external experts
[en] Coarse particulate matter (PM10) concentrations and chemical composition were monitored from 2014 to 2017 at three sampling sites in the Metropolitan Region of Rio de Janeiro, namely Botafogo, Gávea, and Gericinó. All sites are located close to the 2016 Olympic Game arenas. The average annual PM10 concentrations were above the limits recommended by the World Health Organization (WHO) at all sampling sites. Of all the analyzed water-soluble ions, the highest concentrations were obtained for NO3-, SO42-, Cl- and Na+. Sulfate displayed a higher anthropic contribution (ca. 70%). Iron and copper were present in all samples, originated from soil resuspension and traffic (fuels and brakes, among others). Overall, civil works to restructure the city and the construction of the Olympic Game arenas increased PM10 and some of its constituent levels prior to 2016. After the Olympic Games, PM10 concentrations have decreased, due to governmental policies regarding traffic planning and civil work finalization. (author)
[en] This study proposes a method to convert non-structural calcium-rich construction and demolition waste fines into adsorbents of heavy metal ions by mixing waste fines with diammonium hydrogen phosphate solution to produce hydroxyapatite, which has high surface areas and excellent ion-exchange capacity with heavy metal ions. As a result, environmental polluting waste is converted into environmentally cleaning material. Waste putty powders was chosen as the representative waste to investigate the detailed formation process of hydroxyapatite and the key reaction parameters of the reaction. Results showed that hydroxyapatite can be produced on waste putty particles. Higher ageing temperatures or longer ageing duration are beneficial to the yield and crystallinity of the produced hydroxyapatite. Adsorption testing confirmed that Ni2+ can replace Ca2+ in the hydroxyapatite lattice, leading to the formation of a new crystal, arupite (Ni3(PO4)2•8H2O), and contributing to a modest adsorption capacity for Ni2+ (15 mg/g) for the hydroxyapatite-containing waste putty.
[es]Este estudio propone un método para convertir residuos de construcción y demolición no estructurales, ricos en calcio y pulverulentos, en adsorbentes de iones de metales pesados mezclándolos con una solución de hidrógenofosfato de diamonio para generar hidroxiapatita, la cual presenta una elevada área superficial y una excelente capacidad de intercambio iónico de iones de metales pesados. De este modo, un residuo contaminante se convierte en un material que limpia el medio ambiente. Se seleccionó residuo en forma de masilla en polvo como residuo representativo para investigar en detalle los procesos de formación de hidroxiapatita y los parámetros clave implicados en la reacción. Los resultados mostraron que la hidroxiapatita se puede producir en las partículas de los residuos empleados. La producción y la cristalinidad de la hidroxiapatita se ve favorecida por temperaturas de envejecimiento elevadas y prolongadas. Los ensayos de adsorción confirmaron que el Ni2+ puede sustituir al Ca2+ en la estructura de la hidroxiapatita, formándose un nuevo mineral, arupita (Ni3(PO4)2•8H2O), y contribuyendo a una adsorción modesta de Ni2+ (15 mg/g) por parte de la masilla de residuos con hidroxiapatita
[en] The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies for geological disposal of High-level Radioactive Waste through investigations of the deep geological environment within the host sedimentary rock at Horonobe Town in Hokkaido, north Japan. The investigations will be conducted in three phases, namely 'Phase 1: Surface based investigations', 'Phase 2: Construction phase' (investigations during construction of the underground facilities) and 'Phase 3: Operation phase' (research in the underground facilities). According to the research plan described in the 3rd Mid- and Long-term Plan of JAEA, 'Near-field performance study', 'Demonstration of repository design option', and 'Verification of crustal-movement buffering capacity of sedimentary rocks' are important issues of the Horonobe URL Project, and schedule of future research and backfill plans of the project will be decided by the end of 2019 Fiscal Year. The present report summarizes the research and development activities of these 3 important issues carried out during 3rd Medium to Long-term Research Phase. (author)
[en] NORs (Naturally Occurring Radionuclides) are present at varying concentrations in the Earth crust and consequently also will be present in natural concentrations in gas and oil reservoirs. The NOR concentrations in well fluids may become enhanced due to extraction processes and subsequently form NOR enriched deposits within production facilities, thereby forming NORM (Naturally Occurring Radioactive Material). Examples include produced water, scales, sludge and pigging debris. Uncontrolled work activities involving NORM can lead to unwanted exposure and dispersal posing a risk to human health and the environment. These risks or doses, stemming from the exposure to ionizing radiation emerging from NORM, can be reduced by the adoption of appropriate controls to identify if and where NORM is present. The general principles of protection against the hazards of ionizing radiation are primarily implemented by utilizing best working practices at NORM work areas. In this respect exposure control and adequate dosimetry are the most critical components of a health and safety programme in the protection of workers. The protection of the environment, and subsequently the public at large, is achieved by controlled disposal of NORM-waste and the adoption of emission control. (author)
[en] At the dismantling of FBFC International's fuel fabrication plant in Dcssci/Bclgium, more than 34.000 tons of soil have already been successfully characterized and sorted by NUKEM's system FREMES until end of July 2020. The measurement and sorting process is executed fully automated and can process up to 13 tons per hour, having involved recording and evaluation of up to 16.500 gamma spectra per day. To ensure the constant quality of the results, a clear-cut algorithm as well as regular consistency checks and supervision are essential. This article describes the principal data evaluation of the system from recording to sorting, and gives an overview about the taken measures of data analysis and quality assurance. Practical representations and typical examples from operational experience illustrate, how the system reliably performs highly numerous and frequent gamma measurements, without necessary expertise of the site operators.
[en] Fukushima Prefecture was contaminated with large amounts of radioactive materials by the accident at Fukushima Daiichi Nuclear Power Station caused by the Tohoku-Pacific Ocean Earthquake of March 11, 2011. Although decontamination based on the Act on Special Measures Concerning the Handling of Radioactive Pollution has been implemented, it was completed in the municipal decontamination area by the end of March 2018 which is seven years after the accident. This study discusses issues of decontamination one year and a half after completion of decontamination in the municipal decontamination area of Fukushima Prefecture based on questionnaire surveys to municipalities. This study clarifies that many issues concerning decontamination are left. This study identifies (1) early convey of contaminated soils and wastes to interim storage facilities, restoration of temporary storage sites corresponding to conditions and consideration of long-term storage and management of removed soils and wastes, (2) implementation of 'decontamination' of forests, rivers and water channels to restore environments based on a new act, and (3) implementation of follow-up decontamination in accordance with the characteristics of places as one of a mean of radiation protection measures as main issues concerning decontamination at one year and a half after completion of decontamination. (author)
[en] Monitoring contaminants in the marine environment is a prerequisite for the development of accurate environmental assessments and for evaluating the effectiveness of pollution control. Such assessments and evaluations can only be valid if the monitoring results, obtained in different places and at different times, are comparable. Comparability of the environmental data is only achievable when results are traceable to a common system of reference. Because of the need to base scientific conclusions on valid and internationally comparable measurement results, and to provide policy makers with correct information on the state of the environment, it is indispensable to ensure the quality of measurement results produced by laboratories involved in marine monitoring studies. Since the 1960s, the IAEA has been providing help to its Member States in the field of data quality and quality assurance. To support Member States in their monitoring activities, the IAEA Environment Laboratories produce certified reference materials (CRMs) characterized for trace elements and methylmercury using samples of marine origin — biota and sediments. This publication describes the production of a new CRM for trace element mass fractions in a sediment matrix in accordance with the requirements of international guidelines for the production and characterization of CRMs. Eight laboratories with demonstrated measurement capabilities participated in the characterization of the sediment sample. The IAEA-475 sediment sample was produced in the frame of a Peaceful Uses Initiative project for the production of a CRM for trace elements and organic contaminants in marine sediment from the Pacific. The sediment matrix used for the IAEA-475 sample is from the Australian marine coastal zone and is an appropriate matrix CRM for monitoring studies along the Australian coast.
[en] The Horonobe Underground Research Laboratory Project is planned to extend over a period 20 years. The investigations will be conducted in three phases, namely “Phase 1: Surface-based investigations”, “Phase 2: Construction Phase” (investigations during construction of the underground facilities) and “Phase 3: Operation phase” (research in the underground facilities). This report summarizes the results of the investigations for the 2018 fiscal year (2018/2019). The investigations, which are composed of “Geoscientific research” and “R&D on geological disposal technology”, were carried out according to “Horonobe Underground Research Laboratory Project Investigation Program for the 2018 fiscal year”. The results of these investigations, along with the results which were obtained in other departments of Japan Atomic Energy Agency (JAEA), are properly offered to the implementations and the safety regulations. For the sake of this, JAEA has proceeded with the project in collaboration with experts from domestic and overseas research organizations. (author)