You Put It Where?
Petroleum fuels for power plants are expensive and polluting. These resources are also becoming scarcer each year. There is a great deal of conversation about the advantages of nuclear power plants. However, there is one major problem: where do we put the waste nuclear materials after they have decreased in radioactivity to the point they can no longer be used as fuel for the power plant?
Why It Matters
- Nuclear power plants operate by heating water to make steam that drives a turbine, generating electricity. The heat comes from decay of the radioactive material and by nuclear fission, where a neutron causes a radioactive isotope to split into two smaller isotopes, releasing energy in the process.
- Nuclear waste arises from both the fission fragments (smaller atoms from the splitting of a radionuclide) and atoms of the original material that has decreased in radioactivity. Both of these materials are still very radioactive. Unless they are going to be reprocessed, these products need to be disposed of somewhere that will not be an environmental problem or expose people to radioactivity.
- Many building products contain very low amounts of natural radioactivity. These materials do not represent a hazard to anyone and are therefore exempt from regulation. Hospitals and other medical facilities usually employ radioisotopes with very short half-lives, so they do not need to take special precautions for disposal.
- Watch a video that looks at some of the issues and solutions for disposal of nuclear waste: https://www.youtube.com/watch?v=mXH2rBRVAuc
Show What You Know
Use the links below to learn more about half-lives and nuclear disposal. Then answer the following questions.
- Why is the half-life of a radioactive isotope important?
- What is high-level waste?
- What is the yearly exposure from wearing a watch with a luminous dial?
- Can used fuel be reprocessed?