Euradwaste '08 - EU Bookshop - Europa
Euradwaste '08 - EU Bookshop - Europa Euradwaste '08 - EU Bookshop - Europa
Close dialogue between a regulator and a developer is beneficial to the development of a safety case and a licence application, but the dialogue must be controlled and documented and not compromise a regulator’s freedom to make decisions. 5. Conclusions There is a high level of awareness of the importance of treating uncertainties in PA and the safety case, and treatments of varying degrees of sophistication have been implemented in all national programmes. The PAMINA project is making a significant contribution and the final guidance report from RTDC-2 on the treatment of uncertainty, to be available in late 2009, will summarise this work and will form a key international reference for both performance assessors and regulators. 6. Acknowledgements The authors acknowledge the support of the EC under contract FP6-036404, and co-funding received from ONDRAF/NIRAS (Belgium), NDA (UK), Nagra (Switzerland), and SSM (Sweden). References [1] Galson, D.A. and Khursheed, A. (2007). The treatment of uncertainty in performance assessment and safety case development. In: Proceedings of 11 th Int. Conf. on Env. Remed. and Radioactive Waste Management ICEM2007 (2-6 September 2007, Bruges). ASME. [2] Hooker, P.J. and Greulich-Smith, T. (2008). Report on the PAMINA Stakeholder Workshop: Communicating Safety Issues for a Geological Repository. PAMINA Deliverable D2.1.B.1. Galson Sciences Limited, UK [http://www.ip-pamina.eu/publications/reports/index.html]. [3] Norris, S. (2008). Uncertainties associated with Modelling the Consequences of Gas. PA- MINA Deliverable D2.2.B.2. Nuclear Decommissioning Authority, UK [ibid]. [4] Luukkonen, A. and Hordman, H. (2008). A hydro-geochemical change in an engineered barrier system – two model responses to uranium transport. PAMINA Deliverable D2.2.B.3. Technical Research Centre of Finland [ibid]. [5] Hooker, P, and Wilmot, R. (2008). Report on the PAMINA Workshop on the Regulatory Role in Managing Uncertainties in the Safety Case for Geological Disposal of Radioactive Wastes. PAMINA Deliverable D2.1.A.1. Galson Sciences Limited, UK [ibid]. [6] Environment Agency and Northern Ireland Environment Agency (2009). Geological Disposal Facilities on Land for Solid Radioactive Wastes: Guidance on Requirements for Authorisation. 386
Sensitivity Analysis Techniques for the Performance Assessment of a RadioactiveWaste Repository Ricardo Bolado Lavín 1 , Klaus-Jürgen Röhlig 2 , Dirk-Alexander Becker 3 1 Institute for Energy, European Commission DG-JRC, Petten, The Netherlands 2 Technical University of Clausthal, Germany 3 GRS-Braunschweig, Germany Summary� Sensitivity Analysis (SA) is a key element in the Performance Assessment (PA) of a Radioactive High Level Waste (HLW) Repository. It helps gaining information about the system, understanding the relation between input parameters and output variables and steering new experimental and theoretical research to increase the degree of knowledge about the system. The Integrated Project (IP) PAMINA is devoting a large effort to the research in this area and the dissemination of results among its partners. Among the activities under development are a review of SA methods, a benchmark of SA techniques and the application of different SA techniques to a PA results coming from several national programs. After the end of this activity, PAMINA partners will get a better understanding of the rationale behind every available technique and about their capabilities and shortcomings. 1. Introduction SA methods may be divided into three broad types: Local methods, screening methods and global methods. Local methods focus on the study of the system model behaviour under very specific system conditions (the vicinity of an input space point), while screening methods focus on the functional relation between inputs and outputs disregarding input parameter distributions, and global methods focus on how the whole input space (taking into account input distributions) maps into the output space. Though all of them are important and provide relevant information about the system model, screening methods and global methods fit better within the structure of a PA, and that is the reason to focus all efforts on them. Three main activities are being developed in this area: the review of SA methods available in the scientific literature, the development of a benchmark on SA techniques and the practical application of SA techniques to results of PA studies produced by different partners. The objective of the review of SA techniques is to provide a snapshot of most useful SA techniques and to provide guidance about merits and shortcomings of each one. Screening techniques are useful to identify irrelevant input parameters that can be set to their nominal value not losing information. Global methods may be classified as Monte Carlo based methods, variance based methods, and graphical methods. The SA benchmark has been designed as a two-step process. The first step is dedicated to analyse a set of mathematical functions most of whose sensitivity indices are well known. The targets in this step are to debug SA computational tools used, to get skills in their use and to get progressively in contact with specific features of mathematical models such as (lack of) linearity, (lack of) monot- 387
- Page 352 and 353: form. Clay colloids were detected i
- Page 354 and 355: References [1] Retrock (2005). Trea
- Page 356 and 357: vance on radionuclide migration. Ma
- Page 358 and 359: 342
- Page 360 and 361: The Ruprechtov site, located in the
- Page 362 and 363: Colloid Concentration / μg/l 10000
- Page 364 and 365: exists as a stable mineral phase in
- Page 366 and 367: pared to other sites with SOC-beari
- Page 368 and 369: [3] Hauser, W. Geckeis, H., Götz,
- Page 370 and 371: The science and technology group, r
- Page 372 and 373: FEPCAT RTDC 1 RTDC 2 RTDC 3 Clay-ri
- Page 374 and 375: A1: Transport mechanisms Diffusivit
- Page 376 and 377: 360
- Page 378 and 379: maintaining and develop competence
- Page 380 and 381: A project would be justified to det
- Page 382 and 383: 366
- Page 384 and 385: 368
- Page 386 and 387: The main goal of RTDC-1 is to provi
- Page 388 and 389: 3. RTDC3 In RTD component 3 methodo
- Page 390 and 391: lower depths are less saline. For t
- Page 392 and 393: [3] Marivoet, J., Beuth, T., Alonso
- Page 394 and 395: certainty, conducted in RTDC-1 as W
- Page 396 and 397: A simplistic summary might place PA
- Page 398 and 399: There are at least three non-numeri
- Page 400 and 401: 10-11 June 2008. The workshop was a
- Page 404 and 405: ony, interactions, etc., and to che
- Page 406 and 407: specific sampling strategy, with th
- Page 408 and 409: 2.2.3 Graphical methods Let us call
- Page 410 and 411: 3. The sensitivity analysis benchma
- Page 412 and 413: 4. Discussion and conclusions Three
- Page 414 and 415: 398
- Page 416 and 417: 2. Methodology The project particip
- Page 418 and 419: Closely related to this proposal on
- Page 420 and 421: 4.3 Structure The TP structure must
- Page 422 and 423: 4.5 Implementation It is proposed t
- Page 424 and 425: 5.1 The CARD Project has shown that
- Page 426 and 427: � What steps should be taken to m
- Page 428 and 429: 412
- Page 430 and 431: 414
- Page 432 and 433: materials. For attaining the stated
- Page 434 and 435: the bottom of the heated press-mold
- Page 436 and 437: 420
- Page 438 and 439: 422
- Page 440 and 441: focuses on the study of the combine
- Page 442 and 443: emitting radioactive waste to study
- Page 444 and 445: 428
- Page 446 and 447: 2.1 Laboratory experiment The dispo
- Page 448 and 449: 3. Results 3.1 Laboratory experimen
- Page 450 and 451: Barrier. Clays in Natural & Enginee
Close dialogue between a regulator and a developer is beneficial to the development of a safety<br />
case and a licence application, but the dialogue must be controlled and documented and not compromise<br />
a regulator’s freedom to make decisions.<br />
5. Conclusions<br />
There is a high level of awareness of the importance of treating uncertainties in PA and the safety<br />
case, and treatments of varying degrees of sophistication have been implemented in all national programmes.<br />
The PAMINA project is making a significant contribution and the final guidance report<br />
from RTDC-2 on the treatment of uncertainty, to be available in late 2009, will summarise this<br />
work and will form a key international reference for both performance assessors and regulators.<br />
6. Acknowledgements<br />
The authors acknowledge the support of the EC under contract FP6-036404, and co-funding received<br />
from ONDRAF/NIRAS (Belgium), NDA (UK), Nagra (Switzerland), and SSM (Sweden).<br />
References<br />
[1] Galson, D.A. and Khursheed, A. (2007). The treatment of uncertainty in performance assessment<br />
and safety case development. In: Proceedings of 11 th Int. Conf. on Env. Remed. and<br />
Radioactive Waste Management ICEM2007 (2-6 September 2007, Bruges). ASME.<br />
[2] Hooker, P.J. and Greulich-Smith, T. (2008). Report on the PAMINA Stakeholder Workshop:<br />
Communicating Safety Issues for a Geological Repository. PAMINA Deliverable D2.1.B.1.<br />
Galson Sciences Limited, UK [http://www.ip-pamina.eu/publications/reports/index.html].<br />
[3] Norris, S. (2008). Uncertainties associated with Modelling the Consequences of Gas. PA-<br />
MINA Deliverable D2.2.B.2. Nuclear Decommissioning Authority, UK [ibid].<br />
[4] Luukkonen, A. and Hordman, H. (2008). A hydro-geochemical change in an engineered barrier<br />
system – two model responses to uranium transport. PAMINA Deliverable D2.2.B.3.<br />
Technical Research Centre of Finland [ibid].<br />
[5] Hooker, P, and Wilmot, R. (2008). Report on the PAMINA Workshop on the Regulatory<br />
Role in Managing Uncertainties in the Safety Case for Geological Disposal of Radioactive<br />
Wastes. PAMINA Deliverable D2.1.A.1. Galson Sciences Limited, UK [ibid].<br />
[6] Environment Agency and Northern Ireland Environment Agency (2009). Geological Disposal<br />
Facilities on Land for Solid Radioactive Wastes: Guidance on Requirements for Authorisation.<br />
386
Change language