By John Stang
A California watchdog organization has petitioned the U.S. Nuclear Regulatory Commission to significantly increase the required longevity of the dry casks used for storage of spent nuclear reactor fuel at power plants around the country.
On Jan. 2, Citizens’ Oversight submitted the petition for rulemaking that argued the 40-year design life required for NRC licensing of spent fuel canisters is much too short. The San Diego-area group believes the canisters nationwide should have a 1,000-year lifespan with maintenance and a 300-year lifespan without maintenance.
“It appears as this juncture … the NRC is relying on some magical solution to be developed to deal with the wastes once the current dry storage facilities (ISFSIs) start to reach their useful life since the time horizon of the NRC license is only 40 years,” Citizens’ Oversight said in its petition.
An NRC spokesman said staff at the nuclear industry regulator anticipates in March issuing a Federal Register describing what steps it expects to take on the petition. The staff’s response to the petition is expected by the end of this year. If the petition results in a full rulemaking, that process can require more than a year to complete.
“Speaking generally, the term of an NRC-issued license is not tied to aspects of the longevity of the underlying technology. The issues of dry cask certification and dry cask facility licensing have been raised in previous petitions,” the spokesman said by email.
While Citizens’ Oversight is pushing its own concept for a double-walled canister, the organization is open to NRC considering other potential designs, founder Ray Lutz said. The group’s own proposal is called Hardened, Extended-Life, Local, Monitored, Surface Storage, or HELMS, a double-walled canister with pressured helium gas between the two shells. A drop in the helium pressure would make it easier for nuclear operators to detect a crack in the shell, Lutz said.
“I don’t think (HELMS) will be something that will be immediately embraced. It’ll probably take some time to be (mentally) processed,” Lutz said.
Lutz speculated that the NRC’s review of the petition and any resulting changes in regulations will take longer than it takes the shuttered San Onofre Nuclear Generating Station (SONGS) in San Diego County to complete its transfer of spent nuclear fuel from wet pools to dry storage.
SONGS permanently shut down in 2013, and majority owner Southern California Edison recently began moving the remainder of its spent fuel to a dry storage pad close to the Pacific coast. The process is expected to be complete in mid-2019.
In a 2017 settlement to a lawsuit filed by Citizens’ Oversight, the utility has committed to seeking avenues to move the radioactive waste off-site.
The U.S. Department of Energy is legally required to place spent fuel from all U.S. nuclear power plants into permanent disposal. However, it is more than two decades past the Jan. 31, 1998, deadline to begin accepting the fuel.
Lutz contended a HELMS system or another system should be in place when San Onofre’s spent fuel is sent to another location.
Southern California Edison has declared that its overall dry cask storage system at SONGS, Holtec’s HI-STORM UMAX, is designed to withstand floods, projectiles from a tornado, earthquakes, extreme temperatures and lightning. It has said its earthquake resistance standards are the strictest in the nation among nuclear facilities.
