There are a number of ways to treat nuclear waste, and one of the more promising is vitrification. That is, mixing filtered waste with glass-forming materials, then heating it in a furnace to create borosilicate glass, which remains stable for thousands of years. Developing this method has usually concentrated on high-level nuclear waste like spent fuel rods, but there’s a hundred times more low-level waste. That is, waste materials that have been contaminated by radioactive elements or have been exposed to neutron radiation. These can include decayed medical isotopes, contaminated clothing, laboratory animal carcasses, and a lot of low-activity reactor residue in liquid form.