HAL Workstream

Highly Active Liquors (HAL) is classed as high level waste and is a by-product of reprocessing spent nuclear fuel. It is treated at Sellafield in the vitrification plant where it is converted into a solid stable form for transport and long term storage.

HAL Workstream
HAL Workstream


At Sellafield, processes have been developed for the processing of high level wastes, including highly active liquors (HAL), a result of reprocessing irradiated nuclear fuel.

HAL is stored in Highly Active Storage Tanks which provide controlled storage conditions including cooling, agitation and monitoring.

At the Sellafield site, HAL has been safely stored for more than 40 years. A vitrification technology has been implemented where the liquid waste is converted to a stable, solid state suitable for transport and long term storage.

This process takes place at Sellafield in the Vitrification Plant which has been in operation since 1991. Here the liquid high level waste is turned into dense solid glass blocks and reduces the liquid waste volume to about a third of the original liquid waste size. 

Vitrification involves drying the liquid waste to a powder, mixing it with glass and heating it to a temperature of around 1,200 degrees Celsius. 

The molten mixture is poured into stainless steel containers and allowed to solidify. The vitrified waste is then placed into a specially engineered Vitrified Product Store pending final disposal in the UK or return to its country of origin.

Returning this waste to overseas customers fulfils contractual obligations and also UK government policy, which states that the waste from reprocessing contracts signed since 1976 should be returned to the country that benefited from the reprocessed fuel.