I think even the most ardent advocates of Thorium would have to grant that Thorium is neither clean or safe. It is only comparatively so when talking of other nuclear fuels. I bet that these groupies of the nuclear industry would not let their kids near Thorium waste for 500 years.

I understand that its reputation as 'clean' derives partly from the fact that a Thorium reactor can use waste from conventional reactors and its advocates say that it can thus be used to convert waste which will be lethal for thousands of years into stuff that is only deadly for 500 years. It is seen as a 'cleaner' technology rather than a 'clean' one. And it is seen as a clean-up technology rather than a 'clean' one. It probably will be a serious consideration for the nuclear club when that party sees an end to cheap Uranium and the increasing cost of Uranium wastes. Could we call that Peak Uranium? At that time look for full development of this partly developed Thorium technology.