Summary of ITAC

1. Date of the meeting

1st 3- 5 December, 2001 1st ITAC/DTAC Joint Meeting 19 July, 2002

2nd 10-12 April, 2002

3rd 16-18 July, 2002

2. Members

Chairman Dr. Charles McCombie Independent Consultant and Director of ARIUS, Switzerland
  Dr. Johan Andersson President, JA Streamflow AB,Sweden
  Dr. Mick Apted President, Monitor Scientific LLC,USA
  Prof. Neil Chapman Professor of Environment Geology, Sheffield University, UK
  Mr. Bernard Faucher
(from 3rd meeting)
International Department, ANDRA, France
  Dr. Ian McKinley Director, International Services & Projects, Nagra, Switzerland
  Dr. Juhani Vira Research Director, Posiva, Finland
  Dr. Erik Webb Manager, Geohydrology Department, Sandia National Laboratory, USA

3. Discussion

(1) Aims

The aims of ITAC are to provide advice on, and also internal review of, NUMO's strategic planning and technical programmes and to provide a source of experience and information for NUMO project managers.

(2) Focus

The focus for meetings was on reviewing NUMO's site-selection strategy and the associated documents to support the call for volunteers.

(3) Progress

Discussions focused on the policy and structure of the documents. This utilised the experience accumulated over the last few decades in foreign programmes, the wide range of technical knowledge available in advanced disposal programmes and also familiarity with the development of the waste management programmes in Japan.
In reviewing drafts of NUMO's documents, ITAC provided input to ensure their technical and scientific accuracy, openness, transparency and traceability.

(4) 1st Joint Meeting

An ITAC/DTAC(Domestic Technical Advisory Committee) Joint Meeting was held to help integrate advice from these two bodies. It was evident that there were many more areas of consensus between DTAC and ITAC than there were areas of disagreement.


Major comments from ITAC are listed in the appendix.
Appendix Major comments from ITAC 1~3 and joint Meeting

1. Overall

(1) ITAC agreed with the basic content of the documentation proposed by NUMO to support the site-solicitation process. It was felt that an additional summary document might be useful. This would then give 3 documentation levels:

Level 1 comprising a single integrating document which can be widely distributed during the solicitation stage.

  • Level 2 as already proposed with SF(Siting Factors), RC(Repository Concepts), etc as separate documents is good, but it was emphasised that they need careful co-ordination. In detail, it was also noted that:
    • close link between SF and RC is vital: this could be emphasised at Level 1;
    • the “benefits” document should be wider than just financial (other positive social and economic aspects).
  • Level 3 documents to understand the scientific and technical basis for the assertions made by the Level 2 documents: these can, in principle, be left until later (they may be difficult to produce on the timescales stated and may not even be required at such times, but will be vital later).

(2) QA is an extremely important topic which should be considered with high priority.

(3) An external, “non-expert” review of level 1 and 2 documents would also be valuable (less expert than students).

(4) ITAC suggest that focused workshops, working groups or review teams could help bring together Japanese and foreign experts.

(5) The NUMO siting process is unique and corresponds to modern ethical principles.
It would be good for NUMO to highlight this in level 1 and 2 documents, and explain why this approach was chosen and take credit due.

2. Siting Factors (SF)

(1) Classification into three groups is good and reflects the Japanese law. However,it may be useful to re-name categories (names instead of numbers):

  • Category1: Evaluation Factors for Qualification (EFQ)
    • Category1a: Nationwide Evaluation Factors (NEF)
    • Category1b: Site-specific Evaluation Factors (SSEF)
  • Category2: Favourable Factors (FF).

(2) Exclusion Factors must be quantified and justified before documents are produced

(3) The current imprecise nature of Favourable Factors should be extended, defined and described comprehensively before PIAs (Preliminary Investigation Areas) are chosen. Current list is dominated by "geology": also needs to include feasibility, cost, transport, environmental & social impacts, etc.

(4) Need to consider how and when to use reactor and other nuclear plant seismic risk criteria to check suitability for repository surface facilities.

(5) Clear formulation of resource issue: e.g. emphasising that presently worked resources just for screening - abandoned mines and distribution of mineral resources will be considered at later stage.

(6) Definitions of volunteer areas, PIAs, DIAs (Detailed Investigation Areas) and supplementary investigation area are needed.

(7) Maybe add a box describing impact of all non-nuclear (i.e. planning) legal requirements on acceptability of a volunteer. The figure showing selection procedure appears too complex and should better show how NUMO will offer help to municipalities, not just offer to provide “details”.

(8) ITAC agrees with idea of a glossary, but note also that general terminology needs tidying up.

3. Repository Concepts (RC)

(1) The English name “Repository Concepts” would be more appropriate than the “Repository Concepts Catalogue”.

(2) Illustrations are very important in RC document:

  • Think about what the message of each is & how to express it clearly.
  • Separate illustrations could realistically show what the surface facilities and activities (including site investigations), underground facilities and the associated geological environment could look like.
  • Illustrate examples of potential & feasible EBS (Engineered Barrier System) designs.
  • Illustrate chosen examples (not matrix) of realistic geological environments of Japan where it would be feasible to build a repository and explain what the safety-relevant features are for each.
  • Explain how RCs & EBSs might be associated with each example.
  • Try to emphasise security (fences, etc) in illustrations (concern about terrorism).
  • Add more people in illustrations wherever relevant to provide scale and atmosphere of safety.

(3) Explain that the Favourable Factors in SFs can be quantified fully only after selection of a site and repository concept but do not overemphasise significance of any SF in RC (e.g small groundwater movement).

(4) Probably best not to present performance assessment for RC, but instead explain the safety functions of each concept qualitatively - how the concept “works” and what its implications will be for SFs (Note: it is important to carry outperformance assessment in-house to explore each concept, but this is extremely difficult to present to a non-specialist audience and may often be difficult to present to many specialists).

(5) It is better not to use term “reference design”; add scale bars; show a wider range of realistic designs considered by NUMO (if necessary, refer to international pictures and examples).