The experimental procedure consists of excavating a cavern, emplacing the engineered barrier systems (concrete silo, sand/bentonite buffer) and injecting gas in the centre of the concrete silo.

Laboratory studies, detailed site characterisation activities (hydrogeological, rock mechanical) and modelling studies complement the main experiment.

Experimental Concept Plan

How would gas injected inside the concrete silo move through the sand / bentonite?

Four different gas flow regimes can occur according to

1. gas generation rates
   
2. the confining stress
   

NB for low flow rates, diffusion in solution is also a possibility.

Classic Displacement flow: Gas Pressure < Confining Stress	Flow around silo: Gas Pressure > Vertical and Horizontal Confining Stress
Flow along top of silo: Gas Pressure > Vertical Confining Stress	Fracture of EBS: Gas Pressure >>Confining Stress