Annual Report for 2010/11 and Forward Programme - Sellafield Ltd

SSEM/2011/4730 June 2011Particle chemical composition based on EDX measurements of the surface have shown:• EDX scans focus on a point of interest or a small area and can therefore varysignificantly over the surface of a single particle. This variation may be due tochanges in the surface composition or the shielding affects of other materialsstuck to a particle surface. For example, the interfering presence of salt crystalson the particle surface has reduced the information available for tranche 1 and 2particles. To solve this problem tranche 3 particles have been washed prior toEDX measurements.• Iron oxide is strongly represented in both alpha-rich and beta-rich particles, as issilica and calcite.• Aluminium is present, with the highest concentration associated with a highlyfragmented particle.• The two metallic particles that have a metallic swarf appearance havecomponents found in stainless steel.• Zirconium is present in a range of concentrations but mostly either high (i.e. >80%) or low (i.e.