What to do with Radioactive Waste
Nuclear power plants do have a waste management problem because radioactivity takes a long time to dissipate and turn the radioactive waste into just a non-hazardous waste. Radioactive wastes are wastes that contain radioactive material. Radioactive wastes are usually by-products of nuclear power generation and other applications of nuclear fission or nuclear technology, such as research and medicine. A new draft nuclear waste management bill released today by four U.S. senators focuses on establishing interim and permanent waste repositories but fails to address current unsafe waste management practices at nuclear power plants across the country, according to the Union of Concerned Scientists. The senators—Lamar Alexander (R-Tenn.), Dianne Feinstein (D-Calif.), Lisa Murkowski (R-Alaska), and Ron Wyden (D-Ore.)—based their draft on President Obama’s Blue Ribbon Commission on America’s Nuclear Future.
The time frame in question when dealing with radioactive waste ranges from 10,000 to 1,000,000 years, according to studies based on the effect of estimated radiation doses. Researchers suggest that forecasts of health detriment for such periods should be examined critically. Several techniques have been proposed for handling: long term above ground storage, geologic below ground storage, space disposal, and transmutation into less harmful radioactive materials.
"Despite their good intentions, the senators ignored the fact that we have a problem right now with how nuclear plant owners store this highly radioactive waste," said Dave Lochbaum, the director of the Nuclear Safety Project at the Union of Concerned Scientists (UCS). "Even under the rosiest scenario, it will take years to site and build an interim storage facility. That means large quantities of nuclear waste will remain at nuclear plants for a long, long time—and three quarters of it is currently crammed in cooling pools rather than stored in dry casks, which are safer."
More than 30 years ago, nuclear plant owners and the Department of Energy (DOE) struck a deal. The owners agreed to pay into what’s called the Nuclear Waste Fund to help finance DOE construction of a permanent geological repository for nuclear waste by 1998. Fifteen years later there is still no repository, and the DOE has had to pay plant owners millions in damages for breach of contract. Meanwhile, nearly 70,000 metric tons of radioactive nuclear waste—the used, or "spent," nuclear fuel—is building up at plant sites around the country, and nearly 75 percent of it is sitting in overcrowded cooling pools.
What’s so bad about the cooling pools? They lack diverse emergency cooling and water makeup systems and most are not protected by robust containment structures. They also rely on electricity, and are thus vulnerable to events leading to power loss, such as flooding and seismic activity, or to terrorist strikes that cause a loss of water from the pool. Loss of cooling could result in fuel damage and a potentially massive radiological release. Such a scenario was a main concern with the nuclear disaster in Fukushima, Japan, in 2011 where the cooling systems for the facility’s pools failed due to lack of power.
The high density of radioactive fuel in the pools is also a concern. More spent fuel in pools increases the heat load and reduces the response time necessary to address problems. Storing less radioactive material in the pools would mean a smaller radiological release in the event of an accident.
Fortunately there is a more sensible, safer solution: transfer the spent fuel rods to cement and steel casks. Spent fuel rods are cool enough to move out of pools after five years, and more than 80 percent of those sitting in pools today could be put in dry casks. Unlike the pools, dry casks are cooled by a passive air system that doesn’t require electricity to operate.
"Plant owners are going to have to move the spent fuel from the pools to dry casks to ship it to a storage site, anyway," said Lochbaum. "So why not move the fuel into casks now to better protect nearby communities?"
The press release issued today by the four senators alluded to the threat posed by storing spent fuel on-site at nuclear power plants. "Currently there is no central repository for spent nuclear fuel," the release said, "leaving fuel rods to be stored on-site at dozens of commercial nuclear facilities around the country, including areas that are at risk of earthquakes, floods and other natural disasters."
Most countries are considerably ahead of the United States in developing plans for high-level radioactive waste disposal. Sweden and Finland are furthest along in committing to a particular disposal technology, while many others reprocess spent fuel or contract with France or Great Britain to do it, taking back the resulting plutonium and high-level waste.
Whatever disposal site or plan is eventually used there will be opposition to it which is one reason why there has been delays in the past and will be delays in the future.
Radioactive sign image via Wikipedia.