SAFE Barriers - a Systems Approach For Engineered Barriers

Scientific objectives are:
1. To deploy and refine advanced monitoring technologies for simultaneous imaging of THMC variables (pH, temperature, pore-water pressure, swelling etc) within the laboratory. We will embed state-of-the-art micro-to-nano scale wireless devices into bentonite, and combine these with micro-scale geophysical and magnetic monitoring surveys, to illuminate 2D and 3D heterogeneities in THMC behaviour.
2. To integrate these monitoring technologies with experiments to gain a predictive understanding of the THMC evolution of clay-based engineered barriers, and their interfaces, up to the upper-bound of realistic environmental conditions. Interfaces will comprise joints within the clay as well as interfaces to the surrounding rock, cement and waste container. Experiments and modelling will focus on the effects of strong gradients in temperature (<150 degrees C), low pH cements and high salinity (10-40 g/l) across the EBS interfaces, and on the fingering of flow along joints and interfaces that may give rise to a heterogeneous THMC system response.

Beneficiaries of this research fall into all four impact categories:
(i) Knowledge: a major contribution to the expanding global dialogue within the industry about engineered barrier systems (EBS), through development and maintenance of reciprocal relations with major industry-led, international programmes, as well as with other UK projects.
(ii) Society: working closely with the NDA public relations function, we propose to use dynamic, interactive theatre to explore the key issues in EBS implementation with communities in areas of the UK with active nuclear power stations and/or existing surface radwaste management facilities.
(iii) People: work closely with other NDA-sponsored projects (and international initiatives) to develop and implement an inter-institutional programme of 'additional professional formation' for project PhD students and postdocs, involving regular exposure to industrial practice (with NDA and others), and annual events in which young researchers will work in groups on realistic design formulated with our industrial counterparts.
(iv) Economy: We are confident that our 'whole system' approach will offer significant opportunities for cost savings, which we will identify and promote through regular dialogue with NDA planning and design staff.