Sch 5 para 2
In the Table at paragraph 1 “ High Level Waste ” means waste which is radioactive enough for the heat released as a result of radioactive decay to increase significantly its temperature and the temperature of its surroundings and includes— (a) the liquid residue that contains most of the radioactivity from the reprocessing of spent nuclear fuel; (b) this residue once it has solidified; or (c) any other waste with similar radiological characteristics.