Types of Radioactive Waste

High-Level Waste

• There are two types of nuclear reactors, pressurized and boiler water reactors. High-level nuclear waste is spent fuel that remains after use in nuclear reactors. This radioactive waste must be cooled for several years inside deep pools of water. These pools are located onsite or at a special off-site facility. This waste is hazardous because some of it remains radioactive. High-level nuclear waste must constantly undergo a process to cool the remaining radioactive material. This spent fuel is transported to specified storage areas and held in concrete barrels.

Low-Level Waste

• About 90 percent of all nuclear waste is considered low-level and includes everyday items that come into contact with some form of radiation. Nuclear reactors, hospitals, dental offices, university laboratories and food irradiation facilities typically generate low-level nuclear waste materials. Low-level nuclear waste isn't considered dangerous, and it can be disposed of in local landfills. But, it must be handled according to strict classification rules. Class A is 95 percent of most low-level waste, which doesn't have a high amount of radionuclides. Classes B and C have a higher concentration and must adhere to stricter disposal requirements.

Transuranic Waste

• Transuranic waste, or TRU waste, is a classification in the United States. TRU waste contains more than 3700 Bq per gram of elements heavier than uranium. Bq is the basic unit of radioactive decay that is equal to one disintegration per second. TRU waste is usually generated from nuclear waste reprocessing. Even though the U.S. has this classification for nuclear waste, it doesn't use it since the commercial nuclear and technology industry isn't regulated for this waste material.

Other Classifications

• There are non-commercial activities contributing to nuclear waste, and they include uranium mining, mill tailings, mixed low-level waste, by-product materials and Formerly Used Sites Remedial Action Program (FUSRAP) Waste. The Environmental Protection Agency (EPA) regulates the clean-up standards for many of these types of nuclear wastes. FUSRAP sites have existed for decades and are still hazardous because of the effects of ionizing radiation.