Nuclear 'waste' has different forms and different levels of radioactivity. There are low level, intermediate level and high level waste, where the level refers to amount of radioactivity. Each is treated differently.
Here is a general overview of Radioactive Waste Management.
http://www.world-nuclear.org/info/inf04.html
Note the appendices to the side:
Radioactive Waste Management Appendix 1: Treatment and Conditioning of Nuclear Wastes
Radioactive Waste Management Appendix 2: Storage and Disposal Options
Radioactive Waste Management Appendix 3: National Policies
Radioactive Waste Management Appendix 4: National Funding
Radioactive Waste Management Appendix 5: Environmental and Ethical Aspects of Radioactive Waste Management