Army bomb squad specialists have been called to Sellafield nuclear reprocessing plant to deal with hazardous chemicals found in a lab.
The chemicals, which had been stored in the lab since 1992 and were contained within a number of canisters, were discovered during a routine audit at a laboratory at the site in Cumbria.
They are industrial solvents, such as Tetrahydrofuran, which are potentially flammable in liquid states and can crystallise and become unstable when exposed to air.
None of the chemicals are nuclear or radiological materials, a spokesperson for Sellafield said.
After the discovery of the chemicals, which had been stored in the lab since 1992, protocols for handling hazardous chemicals meant the Army Explosive Ordnance Disposal Team were called at around 8pm on Friday night to assess the situation.
The Bomb Squad returned on Saturday to help dispose of the chemicals safely.
A Sellafield spokesperson said the Army team will dig a trench, bury the canisters using sandbags, and detonate them in a controlled manner.
This will create a noise that will be audible off-site, but the Army said there is no cause for alarm.
An area of the site remains cordoned off as a precaution - but the rest of the site is operational and the majority of weekend staff are working normally.