During normal operations, do commercial nuclear power plants release radioactive material?
Yes. Nuclear power plants routinely produce radioactive gases and liquid wastes during normal operations. A plant has tanks designed to store gas and liquid radioactive materials that are generated during normal operation. The radioactive material is held for a period of time to allow for the radioactivity level to decrease before being treated and/or released in a planned, monitored way. This keeps the amount of radioactive material in releases low and within regulatory limits (which are set to ensure releases are well within a safe level of exposure).
Prior to being released, radioactive gases and liquid wastes are sampled and analyzed, and calculations are performed to ensure radioactivity levels are within limits. Once the calculations verify the radioactivity is below regulatory limits, the radioactive material is released in a controlled, monitored process. Advance notifications to the public are not required and are not routinely done when releases are made in accordance with the plant’s procedures and regulations. The plants maintain records of all releases. Routine sampling of water from nearby lakes, ponds, etc., performed by the plant operators and independently by states also provides surveillance and detection of any radioactive liquid releases.
Releases that are unexpected, are not made in accordance with procedures, or are above regulatory limits are reported to the Nuclear Regulatory Commission and to the state.
How is radiation and radioactive material that can expose a member of the public measured around nuclear plants? What do the results tell us?
During normal operations, penetrating radiation (like gamma rays and x rays) emitted from the radioactive materials in the reactor and in the systems and buildings of the plant are not able to expose someone outside the boundary of the plant. Nevertheless, radiation monitors are placed on the fence line surrounding the site to directly measure any radiation exposure that might occur.
Radioactive materials that could cause radiation exposure near nuclear power plants are generally monitored by sampling air, food, and water supplies for radioactivity content. Radioactive emissions may be released to both air and water. The radioactive material in the air could be breathed in directly or could settle or deposit on local vegetation. Therefore, samples are taken of the air emissions and food products such as garden vegetables. Some radioactive material could also land on pasture grasses that cows eat, so milk and vegetation are sampled. Nuclear power plants near bodies of water are required to check for radioactive material in all nearby lakes, ponds, and streams, so water samples are taken from the liquid waste stream from the plant. Other water samples are taken from the nearest public water supplies. Samples of fish are caught and analyzed as well. The amount of radioactive material allowed to be released from power plants is strictly controlled by the utility and regulated by the Nuclear Regulatory Commission.
What went on at Three Mile Island and Chernobyl? Were they different?
Yes, the accidents at Three Mile Island and Chernobyl were very different. In the 65 years since the first nuclear reactor became operational, there have been accidents that have affected people. Two events that affected people outside the immediate plant were Three Mile Island in the United States in 1979 and Chernobyl in the Ukraine in 1986.