1. Summary of the Executive Session TF#22

2. Status of Task 6 Papers and Reports All MG have delivered drafts. Waiting for the overall paper from the reviewer, which is pending on the modelling papers. All MG reports delivered except the updated JAEA/Golder report. Again, waiting for the overall paper from the reviewer, pending on the modelling reports. SKB has to approve the IPR reports. Also, the organisations have to approve to submit the papers. When reports and papers approved, they are public

3. Benefits of Task 6 Posiva: Task 6 gave a good background and some support to the safety case. JAEA: Task 6 gave some experiences for short and long term processes. Next step study internal structure of fractures. Will assess the size of the flow-wetted surface. CRIEPI: Gained experience in data handling, and to connect SC and PA. ANDRA: Task 6 was giving useful input to the Dossier. The same team was doing Task 6 and Dossier. It gave a lot of ideas. SKB: No clear difference between SC and PA, strategy adopted with simplification, Task 6C gave insight to creation of the microstructural model, parameterise building blocks, put the building block, i.e. strategy, intact rock properties of main interest, altered layers are important for the chemistry and the bentonite, can effect the erosion, close far-field is important for the transport, complexity not useful concept. Tracer tests not so useful, but the authorities want to see a summary report of all tracer tests, on-going. Training ground for modellers.

4. Possible Meta Task: Management Compile what we have in the review reports, all tasks Circulate in the Secretariat Review by SKB If approved, bring to TF Use an experienced person to analyse and write the report –Management background

5. Next Task Force meeting NWMO (Nuclear Waste Management Organisation) of Canada is going to host the next Task Force meeting. The main option is October 29 – 31. Back-up is September 4-6, but less time, e.g. for Task 7 work.

6. Side Activities? Examples on possible topics: –Geochemical modelling –Microbial modelling –Need to couple it to some experiment at e.g. Äspö. –We could ask e.g. Karsten Pedersen. –TF EBS is planning some experiments in the near far field including chemistry. –Homework to next Task Force meeting.

7. Task 7 Does the open bh give an bias on the results or not? It gives bias, but give extra information, and how much and what is the consequences. How should we use data and to understand the system? In such a way, that we can describe the natural flow. Need base cases with and without bh for steady state. Task 7b: Not possible to start modelling at TF#23, but preparations should be done to get fast start. Workhop in June to keep up the momentum Discuss a1 and a3 Results on a3 to a5

8. Task 7, continuation Report a1 and a2, together, and a3 – a5 together Draft of a1 and a2 in June! Report a3-a5 by TF#23. The evaluation is done by the reviewer. Need to be approved by the organisations. Final review by SKB. Then public. Report format and template? –No formal Table on content but expectations. –There is a SKB template for IPR. Fill in the spreadsheets. Time plan –7a, done by TF#23 in terms of drafts –7b two more TF meetings after that –7c pending on the outcome