THE monitoring of a leak of radioactive water from a storage silo at Sellafield is still ongoing after almost a year.

In October of last year, Sellafield Ltd revealed that there was a variation in water levels in the Magnox Swarf Storage Silo, which is as big as 132 double-decker buses.

The company said that this was a re-occurrence of an historic water leak from the 1970s.

Sellafield had reassured the public that there was no risk to the community nor the workers.

A spokesman for the nuclear firm said: “This was a known risk and something we planned and prepared for as part of our ongoing work to empty the silo – which stores solid fuel cladding underwater - and permanently remove the hazard.

“Last week we gave an update to the West Cumbria Sites Stakeholder Group’s Risk & Hazard Reduction Working Group confirming that our modelling shows that the liquid will remain in the ground underneath the building for some time.

“There is no risk to our workforce or the wider public and we continue to monitor the situation and engage with our regulators.

“We also continue to explore new learning and technologies from elsewhere in the national and international nuclear industry, but our plan for dealing with the hazard remains the same; remove the waste, demolish the building and then deal with the contaminated ground underneath.”

The leak is believed to be originating from the six older compartments of the Magnox Swarf Storage Silo, which has 22 compartments in total.

The majority of the radioactive material stored there is fuel cladding, which Sellafield says has an intermediate level of radioactivity.

The nuclear firm said that while the water is radioactive, the vast majority of the radioactivity in the building (99.5 per cent) is held within the solid waste.

The water is used to cover the solid radioactive material to keep it cool and prevent fires.

The original six compartments of the silo were built in the 1960s. The building was extended three times up until the 1980s to accommodate more waste.

An original leak in the 1970s ended when the route was ‘plugged’ by solid material in the compartment.