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Sea level rise – a threat to nuclear power stations that is being ignored

For nuclear plants operating on thin margins, growing climate risks prompt tough choices   Climate change creates a number of problems for nuclear power plants that some academics say the industry needs to address soon. UtilityDive, Matthew Bandyk@MatthewBandy- – 11 Sept 20′‘………..Sea Levels

Researchers are projecting that nuclear plants need to be concerned not just with water temperature, but also water levels, especially when severe weather events linked to climate change like hurricanes can cause the water level a plant was designed to handle to rise rapidly.

About 37 GW of nuclear power capacity face “higher exposure to flood risk,” according to the Moody’s report. These include plants along the Atlantic and Gulf coasts, as well as inland plants located on rivers, like the Nebraska Public Power District’s Cooper plant on the Missouri River near the Omaha Public Power District’s now-retired Fort Calhoun plant, which was inundated with flood waters in 2011, forcing the plant to shut down for almost three years.

Over the long term, severe weather and rising sea levels could make the need to solve the puzzle of where to store spent fuel from reactors more urgent.

Due to the failure to develop a central waste repository like the long-stalled Yucca Mountain facility, much of the spent fuel is stored on-site in pools within the reactor that shield the potentially dangerous radiation from the discarded fuel assemblies, or, in the case of older spent fuel, stored in dry casks. Spent fuel pools must be actively cooled to avoid a scenario like the Fukushima disaster in 2011.

A 2020 academic journal article by Jordaan and other Johns Hopkins researchers looked at what would happen to spent fuel pool sites at U.S. nuclear plants if sea levels rose by six feet — as the National Oceanic and Atmospheric Administration has projected could happen over the next 80 years.

Seven plants would be at essentially the same level as coastal water, “meaning that the water will be encroaching on the plant with regularity,” the article said. One active plant — Turkey Point — and two decommissioned plant sites — Humboldt Bay in California and Crystal River in Florida — would “be partially or completely submerged by water” in this scenario. To avoid a Fukushima-like incident or the corrosion of dry casks, the article calls for “a long-term and comprehensive storage plan that is less vulnerable to climate change.”

As part of the regulatory response to Fukushima, U.S. nuclear plants updated their evaluations of the potential hazards they face based on their geographic locations, including floods. In some cases, those flood reevaluations have led to changes at some plants, such as new watertight barriers, according to Uhle.

There has been controversy both within and outside the NRC regarding whether the agency has done enough to ensure plants’ flooding protections are in line with the current estimated threats, which are in some cases far more severe than was thought when plants were initially licensed.

In early 2019, a divided NRC approved a rule incorporating “lessons learned” from Fukushima into regulatory requirements, but it did not contain provisions that would have required more extensive protections against the reevaluated hazards.

“Instead of requiring nuclear power plants to be prepared for the actual flooding and earthquake hazards that could occur at their sites, NRC will allow them to be prepared only for the old, outdated hazards typically calculated decades ago when the science of seismology and hydrology was far less advanced than it is today,” NRC Commissioner Jeff Baran said when explaining his objection to the majority’s decision.

The regulations the NRC stopped short of imposing would have forced plant operators to, in some cases, take flood mitigation steps beyond what the plant was originally designed to withstand, according to Ed Lyman, director of nuclear power safety for the Union of Concerned Scientists, who was a strong critic of the commission’s move. For example, if a building containing critical safety equipment for a plant was built to stay above water in a flood, and new studies showed the potential water level was higher than previously thought, the NRC regulations would not require that building to be moved to a higher location, Lyman said.

“Even without additional concerns from climate change, the plants aren’t protected today,” he said……… https://www.utilitydive.com/news/for-nuclear-plants-operating-on-thin-margins-growing-climate-risks-prompt/584883/

September 12, 2020 - Posted by Christina Macpherson | 2 WORLD, climate change