Part 2 of 3 Parts (Please read Part 1 first)
      Rebecca Weston is the chief operating officer of the Sellafield nuclear facility the U.K. She addressed the 2020 International Atomic Energy Agency Scientific Forum recently. She said, “One of the advantages of wet storage within the pond is that there is easier access to the fuel as opposed to within dry storage casks or within new facilities. It allows for easy access for detection of issues. And it’s certainly an area where the UK has significant experience and knowledge in storage of that wet fuel to date”.
      She pointed out that the flexibility of wet storage is very important. “It’s also important that the wet approach, and utilizing existing facilities, allows us to be flexible for future strategies, whether that’s a changing stance around the fuel cycle or being open to future innovations around either drying or long-term storage of nuclear fuel.” She mentioned that her team at Sellafield had changed the pH of the water in the cooing pools to make it more alkaline which aids in preventing corrosion.
       In her speech, Weston said that the irradiation conditions vary between the different types of reactors deployed in the U.K. For example, light water reactor fuels produce different conditions than advanced gas cooled reactors fuels. This has important implications for storage, but it also needs to be considered for monitoring and sampling procedures that are used for different types of fuel.
      In spite of existing technical challenges, the benefits of dry storage have become more attractive over the past few years. The U.S. Nuclear Regulatory Commission has concluded that spent nuclear fuel storage in both cooling pools and in dry storage casks is safe and reliable. Much of the over seventy thousand tons of spent nuclear fuel is stored onsite at nuclear power plants both in cooling pools and dry casks. Dry cask storage was first used over four decades ago and it is currently rising in popularity.
      It is critical for the U.S. to rapidly expand the use of dry casks storage both on site at nuclear power plants and at temporary storage facilities. It has been estimated that if the U.S. does not move a great deal of spent nuclear fuel from reactor cooling ponds to dry casks in the next few years, within five years, some U.S. nuclear power plants will have to be closed because there will be no room in the cooling pools for spent fuel that needs to be removed in order to refuel the reactors.
      Spent nuclear fuel is moved to dry casks after it has been in a cooling pool for at least one years and it often stays in cooling pools for as much as ten years. This complementary use of both wet and dry spent nuclear fuel has been utilized in the safe decommissioning of several U.S. nuclear power plants from 2000 on.
      Some of the countries that have made use of some form of dry cask storage of spent nuclear fuel include US, Canada, Germany, Switzerland, Spain, Belgium, Sweden, Japan, Armenia, Argentina, Bulgaria, Czech Republic, Hungary, South Korea, and Lithuania.
Please read Part 3 next