The operators of the Sellafield nuclear facility have admitted sending bags of radioactive waste to landfill.
The company was prosecuted by the Environment Agency (EA) and the Office for Nuclear Regulation after four bags of mixed general waste were sent to Lillyhall landfill site, in Workington.
The EA said the bags should have been sent to the low level waste repository, at Drigg, Cumbria, which treats and stores low level radioactive waste consignments.
Sellafield said the error was caused by a new monitoring system which had passed the bags as ‘general’ waste making them exempt from strict disposal controls.
All of the original four bags were retrieved from the landfill site and returned to Sellafield for correct disposal. Checks showed there was no contamination at the site or on the landfill equipment.
Sentencing will take place at Carlisle Crown Court on 8 March.