What is Radioactive Waste?
Radioactive waste is the waste from nuclear fuel that is produced when it has been spent inside a nuclear reactor. In other words, it is a solid, liquid, or gas form of waste that contains radioactive substances. Radioactive waste requires proper storage and disposal, and it is regulated by the Nuclear Regulatory Commission. Failure to regulate radioactive substances could pose a huge threat to society.
Types of Radioactive Waste
There are 5 main types of radioactive waste, and each type requires its own process for clean-up and disposal.
- High level
- Intermediate level
- Mining and Milling
High Level Waste
High-level nuclear waste refers to spent fuel that continues to be present after its use in nuclear reactors. This type of radioactive waste needs years to cool down inside pools that are hundreds of feet deep. This can be very dangerous for the surrounding environment because the substance remains radioactive. It must consistently be kept cool in these pools.
Intermediate-level waste is not as concentrated in radioactive substances as high-level waste is, but it is still dangerous. This kind of waste requires shielding when storing and handling the materials. Intermediate waste can include waste from refurbishment, ion-exchange resins, and metal fuel cladding. Intermediate waste only makes up 4% of all radioactive materials present.
Luckily, over 90% of radioactive material is considered low-level waste. Nuclear reactors, hospitals, dentist offices, and other medical offices can use low-level radioactive waste daily in order to conduct business. Low-level radioactive waste is not threatening and it can be disposed in a landfill. Therefore, no shielding is required when disposing of the waste, but there is still a set protocol, because these substances can become dangerous if not handled properly. Low level waste only has 1% of radioactive material in it.
Mining and Milling Waste
Mining activities can produce clean and mineralized waste rock, which needs to be dug out to access the uranium ore body, although it hardly has any concentration of uranium. Clean waste rock can be used during construction, but mineralized waste rock can leave behind acid that can harm surrounding environments. Mining and milling also produce tailings and waste rock. The tailings material has the consistency of sand when it dries from the water, and consists of 75% of the original radioactive material.
Transuranic waste refers to waste that contains more than 3700 becquerels per gram of elements. This waste is created through reprocessing nuclear waste procedures. Transuranic waste is the least concerning, but still is considered a type of radioactive waste nonetheless.
Storage and Disposal
The NRC regulates the storage and disposal of radioactive waste produced by nuclear power plants. United States nuclear power plants keep their spent nuclear fuel in pools surrounded by thick concrete walls with steel lining. When the pools hit maximum capacity, the older spent fuel can be transferred to dry storage. This is a stainless steel canister engulfed in concrete. After 5 years, spent fuel can be moved to the dry canisters, but the typical wait period is 10 years. The fuel pools and dry storage areas provide proper protection to the environment. This storage method is safe, but should be considered temporary, with disposal being the permanent solution. Currently, there are no facilities available for permanent disposal of high-level waste.