Around 25 tonnes of sodium metal has been removed the Winfrith nuclear site in Dorset, UK.
Work to recover, repackage and dispose of the material (resulting from past research projects at Winfrith, Dounreay, Hunterston and Cadarache in France) was complete in February, according to Research Sites Restoration Ltd.
The sodium was retrieved from the existing storage containers and packaged into 10kg units for incineration at the Tradebe facility at Fawley, and later the Veolia facility at Ellesmere Port.
Due to the potential fire hazard, processing was carried out by specialist contractor NDSL, in a purpose-built tented processing facility, equipped with dehumidification and ventilation equipment, RSRL said.
"The steel vessels were cut open in a dry nitrogen atmosphere, the sodium removed in the tented enclosure, packed in dry nitrogen-filled bags in sealed kegs and, finally, the kegs were over-packed in steel transport drums, blanketed with dry nitrogen," explained project manager Andy Philps.
The sodium retrieval project was launched in 2011, processing work was completed in January 2013 and the last package was sent for incineration at the end of February RSRL said.