High-level waste

High-level waste (HLW) is a type of nuclear waste created by the reprocessing of spent nuclear fuel. It exists in two main forms:

Liquid high-level waste is typically held temporarily in underground tanks pending vitrification. Most of the high-level waste created by the Manhattan project and the weapons programs of the cold war exists in this form because funding for further processing was typically not part of the original weapons programs. Both spent nuclear fuel and vitrified waste are considered as suitable forms for long term disposal, after a period of temporary storage in the case of spent nuclear fuel.