Copeland and Allerdale have been earmarked as potential sites to store high-level radioactive waste.

BBC: Cumbria councils defer nuclear waste storage search

Britain needs to find a site for the long-term underground disposal of high-level radioactive waste.

BBC: Schematic of repository

Britain needs to find a site for the long-term underground disposal of high-level radioactive waste as some if it stays dangerous for 100, 000 years.

BBC: Cumbria ruled out of current nuclear waste dump plans

President George W. Bush approved Yucca Mountain as the site to store the U.S.'s spent fuel and high-level radioactive waste, but President Barack Obama cancelled work on the project in 2009.

CNN: Nuclear disasters: Is the fear realistic?

They contain another, much less radioactive waste called transuranic waste (TRU waste) that is thousands of times less radioactive than high-level waste.

FORBES: The First Amendment Bombs Nuclear Energy By Accident

The Sellafield plant is the UK's largest and most hazardous nuclear site, storing enough high and intermediate level radioactive waste to fill 27 Olympic-sized swimming pools.

BBC: Sellafield inspection after 'intolerable risk' report