Spain has several nuclear power plants which can only burn about 5% of the potential energy in the radioactive fuel. The original intention was to reprocess fuel until it was no longer dangerous. Reprocessing has stopped because it produces plutonium, a fuel that can be used for bombs.

That leaves Spain with a huge problem - several thousands of tons of fuel rods that are both hot and radioactive (and could be used for 'dirty bombs'. The government decided to build a central store like the one already in use in the Netherlands. This has a design life of only one century, during which time we hope to find a better solution. This is probably the safest option for radiation and terrorism at the moment, and much better than trying to manage and guard the existing scattered 'dry stores' at individual power plants.

Objectors have aroused great fear in the public, claiming that this temporary store is really a permanent 'nuclear graveyard' and there will be terrible consequences such as birth defects and poisoned food. No local authority will allow it to be on their soil. Spain is a democracy, so the central government can not simply over-rule local decisions (as would almost certainly happen in the UK)

Objectors say the radioactive waste should never have been produced in the first place, and ought to stop right now. Right or wrong spent fuel and other radioactive waste does exist, and nuclear fuel will probably continue to produce waste for the next decade or two whatever political party is in power. It exists. There are thousands of tons of spent nuclear fuel assemblies scattered around
Spain. Spent nuclear fuel (SNF) needs managing. Experiments and calculations are trying to find a way to harness the residual heat or else 'transmute' the stuff to something less toxic. The Netherlands plant shows that the technology is good for the 100-year storage project (hopefully in that time a better solution will emerge).

The real problem is keeping the spent fuel cool and in safe storage until we find out how to get the residual energy out, or else glue the atoms back together!

The nuclear industry (and the government) have tried all sorts of reasoning, trips to the Netherlands plant and outright bribery - to no effect.

So finally, this is an emotional and social problem that has put the project on hold for years, and is about to cost Spanish taxpayers much more to build and guard several small stores, let alone paying foreign governments a fat premium for long-term storage outside of Spain.