Inhibiting Radionuclide Migration during Deconstruction and Decommissioning using Colloidal Silica Grout

Research will focus on the use of colloidal silica to treat surface soils as a risk mitigation measure for inhibiting airborne and waterborne radionuclide migration, which poses a severe hazard to workers and the environment. Under DISTINCTIVE, we demonstrated that colloidal silica can penetrate low permeability materials (including cement) for hydraulic barrier formation, improved sorption capacity, structural repair and erosion inhibition. It can be injected at surface using extremely small (potentially gravity-driven) fluid pressure, without the need for borehole drilling. Here, research will investigate:

• optimisation of sorption/desorption grout properties by addition of other materials (such as biominerals formed in-situ);
• the feasibility of redeploying the silica grout in the form of in- and ex-situ vitrification of grouted soils, thus minimising waste volumes via redeployment of the silica as an integral component of the final wasteform;
• colloidal silica as a strategy for repair of existing degraded cementitious waste packages;
• combining colloidal silica grout containment and in-situ vitrification with the electro-kinetic technique in WP2.2.

Academic Lead: Rebecca Lunn
Researcher: Gea Pagano
Location: University of Strathclyde

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