Project information

• Objective of WP 1, Analysis of system evolution during early post closure period: Impact on long-term safety functions
• Objective of WP 2, Experimentation on key EBS processes and parameters
• Objective of WP 3, Modeling of short-term effects and extrapolation to long-term evolution
• Objective of WP 4, Analysis of impact on long-term safety and guidance for repository design and construction
• Objective of WP China Mock-up, China-Mock-up Test on Compacted Bentonite-Buffer
• Objective of WP 5, Dissemination
• Objective of WP 6, Project Management

Objective of WP 1, Analysis of system evolution during early post closure period: Impact on long-term safety functions

The early period of repository evolution is characterized by an elevated temperature together with strong thermal and hydraulic gradients (possibly mechanical and chemical as well). The duration of this period is very short in the view of the entire operational timeframe of the repository. However, the processes occurring during this period may have an impact on the performance of the barriers in a longer timescale.

• Task 1.1: Identify important processes during the early evolution of the EBS
• Task 1.2: Describe the current treatment of the early evolution of the EBS in long-term safety assessments for spent nuclear fuel
• Task 1.3: Discuss how the short-term transients will/may affect the long-term performance and the safety functions of the repository.
• Task 1.4: Identify the merits and shortcomings of the current treatment
• Task 1.5: Discuss the needs for additional studies of these issues and how they can support future assessments – give directions to other WPs
• Task 1.6: Define “scenarios” related to events in the early evolution of the EBS.

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Objective of WP 2, Experimentation on key EBS processes and parameters

The overall objectives of this Work Package are:

1. to evaluate the key HM, THM, and THMC processes and parameters taking place during the early evolution of the EBS
2. to provide with a reliable good quality experimental HM, THM and THMC data bases, including different time and spatial scales, as input to the modeling and extrapolation work to be conducted within WP3

All the PEBS experimental work is included in WP2. The Work Package is structured into three different tasks

	Task 2.1, Experimentation on key HM processes and parameters a) Evaluate the key HM processes and parameters taking place during the early evolution of the EBS b) Provide with a reliable good quality experimental HM data base, including different time and spatial scales, as input to the modeling and extrapolation work to be conducted within WP3
	Task 2.2, Experimentation on key THM processes and parameters a) Evaluate the key THM processes and parameters taking place during the early evolution of the EBS b) Provide with a reliable good quality experimental THM data base, including different time and spatial scales, as input to the modeling and extrapolation work to be conducted within WP3.
	Task 2.3, Experimentation on key THM-C processes and parameters a) Evaluate the key THM-C processes and parameters taking place during the early evolution of the EBS b) Provide with a reliable good quality experimental THM-C data base as input to the modeling and extrapolation work to be conducted within WP3

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Objective of WP 3, Modeling of short-term effects and extrapolation to long-term evolution

The overall objectives of this Work Package are:

1. to perform coupled HM, THM, and THMC analyses to provide a sound basis for the interpretation of the various tests planned in the frame of the PEBS WP2,
2. to develop new or improved models as demanded by the calibration of computation results with the actual measured data, and
3. to use the data and improved models for extrapolation to long-term evolution of the repository taking into account the scenarios defined in PEBS WP1 and to investigate model uncertainty and its impact on long-term prediction, thus providing input to PEBS WP4.

	Task 3.1, HM modeling of the Mont Terri Engineered Barrier (EB) Experiment The HM modeling will aim at providing a satisfactory scientific representation and a sound basis for interpretation of the EB hydration phase and of the dismantling data. New or improved constitutive laws adjusted with the experimental data will be developed.
	Task 3.2, THM modeling for the planned heater test HE-E The THM modeling will focus on the design modeling as well as prediction and interpretation of the new HE-E heater test to be performed in the VE microtunnel. Constitutive models developed in earlier projects, such as NF-PRO, will be validated.
	Task 3.3, THM modeling of bentonite buffer The THM modeling will provide a continuing interpretation of the long term FEBEX mock-up test as well as analysis for the long term THM tests performed in cells in the CIEMAT laboratory. Moreover, an extrapolation to the real scale will be undertaken.
	Task 3.4, Modeling of THM-C experiments Most of the THC modeling work performed in the NFPRO IP was carried out within the context of performance assessment (RTDC 5). On the other hand, most of the lab experiments performed within NFPRO on canister corrosion, corrosion-bentonite Interactions and concrete-bentonite Interactions have not been interpreted numerically. There is a clear need to test the models used in performance assessment analyses with data of recent laboratory experiments. The main objective here is to develop advanced multiple-continua THC(m) models for clay barriers and test them with lab and in situ tests.
	Task 3.5, Extrapolation to repository long term evolution The objectives of this task are to use the data and improved models from WP3.1-WP3.4 for extrapolation to long-term evolution of the repository taking into account the scenarios defined in PEBS WP1, and to investigate model uncertainty and its impact on long-term prediction, thus providing input to PEBS WP4.

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Objective of WP 4, Analysis of impact on long-term safety and guidance for repository design and construction

The overall objectives of this Work Package are:

Obtain an overview of the findings of WP2 and WP3 and relate the results and uncertainties to the long-term safety functions of the repository components and to the overall long-term performance of the repository, as outlined in WP1. It is expected that this will provide a more complete description of the thermo-hydro-mechanical-chemical evolution of the near field, a more quantitative basis for relating the evolutionary behaviour of the EBS to the safety functions of the system and a further clarification of the significance of residual uncertainties for long-term performance assessment. Finally, the outcomes will be used to give some guidance regarding repository design, by clarifying the link between long-term safety criteria and design criteria of the EBS.

	Task 4.1, Process related description of early evolution phase of the repository
	Task 4.2, Quantitative discussion of significance of lab results and models in relation to long term safety functions.

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Objective of WP China Mock-up, China-Mock-up Test on Compacted Bentonite-Buffer

The overall objectives of this Work Package are:

China-Mock-up has been proposed according to a preliminary concept of HLW repository in China since 2009. China-Mock-up to evaluate the key THM-C processes will be performed at the laboratory. The test is intended to evaluate THM-C processes taking place in the compacted bentonite-buffer during the early phase of HLW disposal and to provide a reliable database as input to numerical modeling and further investigations.

The overall approach is based on performing experiments according to the needs for additional studies on key processes during the early EBS evolution. The study will make use to the extent possible of on going experiments being conducted in the laboratory of Beijing Research Institute of Uranium Geology (BRIUG).

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Objective of WP 5, Dissemination

The overall objectives of this Work Package are:

Exploitation and dissemination of the results on national, European and international level with different instruments.

	Task 5.1: Dissemination of Results
	Task 5.2: Objectives Task 5.2, Training

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Objective of WP 6, Project Management

The overall objectives of this Work Package are:

Management of the Collaborative Project to match all goals (quality of result, resources, time)

	Task 6.1 Administration
	Task 6.2 Day to day management
	Task 6.3 Scientific management