Page 10 - ImmoCem-PCT-CE Geochem.pdf

PROBLEMS WITH GRANULAR LEACHING TESTS FOR

STABILIZED MATERIALS

• Particle size reduction required for testing in accordance with BS EN 12457 methods provides false results

for stabilised waste forms

• End-over-end leaching systems lead to particle attrition (breakdown) further increasing surface area

• Stabilised waste forms have low internal porosity leading to increased tortuosity and retarded rates of mass
flux which are not captured in granular leaching tests

• Where waste forms retain monolithic structure, this encourages FLOW AROUND (diffusion) rather than
FLOW THROUGH (advection) –application to real world is lost (N.B. ImmoCem >100yrs durability)

• 2003/33/EC was developed based on monolithic tank testing for waste forms with particle size above 40
mm in all direction (implemented in UK) – no need to reduce particle size