Exelon seeks post-decommission emergency plan revisions for Oyster Creek
If you're under age 50 in Ocean County, you've never known life without a 10-mile emergency planning zone around the Oyster Creek Nuclear Power Plant in Lacey Township, or semi-annual siren tests, or potassium iodide pills. But you might, if a request by the generating station's parent company is approved by federal regulators.
Exelon seeks permission to scale back emergency protocols after 2019, when decommissioning begins en route to shutdown of operations.
Exelon seeks a decision by February 22, 2019. If approved, the exemptions would take effect in 2021. The NRC will conduct a public-comment period prior to issuing final determinations. No date has been set.
The decision of whether a 10-mile emergency radius is necessary, operation of the 43 sirens within it, and distribution of KI tablets by the Ocean County Health Department, would likely fall to New Jersey and Ocean County emergency management officials.
Ocean County officials contacted by WOBM News said that cursory discussions had taken place, but that the NRC's decisions would determine the course of future moves on the County's part.
Presumably, NRC approval would signal reduced expenditures by Exelon in the course of post-decommission operations at Oyster Creek.
Neil Sheehan, spokesman for the Nuclear Regulatory Commission, said that the request is consistent with those submitted in previous decommissioning procedures elsewhere in the country. The reactor, essentially, ceases to be a critical matter when it no longer functions.
"When you have an operating reactor, the biggest risks are along the lines of a radioactive steam leak, a pump failure, or some other issue pertaining to the reactor's operation," he explained. "Once a plant shuts down, the biggest risk is the fuel in the spent fuel pool."
Through spokesperson Suzanne D'Ambrosio, Exelon issued its statement regarding the request:
"Protecting the public health and safety will remain the primary focus at Oyster Creek throughout the entire decommissioning process. Exelon is requesting a change in the station’s license from the NRC to ensure the Emergency Plan is aligned with the actual state of the facility after it ceases power operation.
When Oyster Creek ceases operation, stops producing steam and pressure, and fuel is removed from the reactor, much of the formal emergency response plan is no longer needed."
The company compiled data to project the point at which the newest fuel rods will have cooled sufficiently to allow ample reaction time for a problem such as a water leakage and the risk of exposure of spent rods.
"Their analysis shows that 12 months after the plant permanently shuts down, they would have up to 10 hours to respond to that," Sheehan said, adding that regulators would need several months to review the specifications.
"It's fuel in a 40-foot deep pool. If, for some reason, the pool began to drain down, the operators would have time to replenish the water in a number of ways, with on-site pumps and generators," Sheehan explained. "It's a much slower-unfolding event than a reactor event."
However, post-decommissioning evolution varies in each instance, hence the need for lengthy analysis of the Exelon analysis.
"It depends on how long the plant's been in operation, the type of fuel they've used, the amount of fuel that's accumulated in each spent pool. Oyster Creek is tied for the title of oldest nuclear power plant in the country. They have more spent fuel than newer plants," Sheehan pointed out.
At most decommissioned generating stations, Sheehan said, moving spend rods from fuel pools into dry casks becomes a priority, eliminating the risk of a drain-down event.
"We have not received a plan from Exelon regarding what they intend to do with Oyster Creek's spent fuel. They have, obviously, over the years, moved a number of assemblies into dry cask storage. Once they do that, storage takes on a different complexion. Casks have no moving parts, there are no pumps or valves. It is purely convective air flow that keeps the fuel cool."
Such steps presume that the dry casks would be impervious to seismic shifts, or any compromise of the earth that surrounds them. Ocean County was the site of a tremor that caused buildings to shudder within the past decade.
"When cask designs are developed, the designers must be sure that the casks are capable of withstanding earthquake activity, flooding, tornadoes, all host of natural phenomena," Sheehan pointed out. But can stress tests be relied upon, and is there cause for concern if the structures don't live up to the expectations?
Sheehan used a Virginia earthquake of 2011 a case in point. "The epicenter was not far from a nuclear power plant. Some dry casks moved several inches. There was no damage. They were completely able to withstand it. And that was consistent with the analysis."
He went on to say that the storage units are designed to be water-resistant. "Even if water entered the vents used for convective air flow, they would still be able to transfer heat from the fuel to the exterior."
So, what is the need for regulations in this regard, if an operator get approval to circumvent them?
"In fact, the NRC is in the process of changing and revising decommissioning regulations," Sheehan said, but will arrive beyond a point in which it would preclude the need for Exelon to seek exemptions. "That's not supposed to be completed until sometime in 2019. Oyster Creek is moving toward permanent shutdown in 2019."