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Development of reliable nuclide migration database
-For safe geological disposal-
May. 18 , 2009
Geological Isolation Research and Development Directorate of Japan Atomic Energy Agency (JAEA) has been developing a number of databases that will be applied as an important basis for performance assessment (PA) of high-level radioactive waste disposal in Japan.
Nuclide migration database has been opened to the public on Web page of JAEA (URL:http://migrationdb.jaea.go.jp) from April, 2008.
Sorption and diffusion of radionuclides in buffer materials (bentonite) and rocks (see supplement 1) are the key processes in the safe geological disposal of radioactive waste. We have developed the practical and reliable sorption and diffusion database (JAEA-SDB/DDB) by improving the existing SDB/DDB in view of potential future data needs, focusing on assuring the desired quality level and possible applications to parameter-setting for the deep geological environment.
The updated SDB/DDB includes 24,000 Kd data (distribution coefficient) and 3,000 De/Da data (diffusion coefficient) and related experimental information from many different literatures. (see supplement 2)
The following functions are key improved points;
-consistency and linkage between SDB and DDB
-quality assuring(QA) data based on QA guideline
-estimating of parameters and graphing of relation between parameters
-counting and summarizing function for effective access to respective data for parameter setting
The SDB includes a great variety of Kd data which are related with various conditions and methods, and different reliability levels. Accordingly, the QA and classifying criteria/guideline for sorption data has been developed in order to evaluate the reliability of each Kd data (see supplement 3). The QA guideline consists of three main criteria; I) completeness of documentation, II) quality of data, III) consistency of data. The reliability of Kd data in the SDB was evaluated based on the guideline, QA results were added in the SDB. As shown in figure, this QA scheme makes it possible to extract reliable and respective data for Kd-setting in the performance assessment in effective, traceable and transparent manner (see supplement 4).
The new web-based sorption JAEA-SDB/DDB have Japanese/English version and provides free access on the web (see above URL).
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Location of environment monitoring posts measuring amount of
radiation. (details)
International link directory of related websites.
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