The U.S. Nuclear Regulatory Commission has issued an environmental assessment and finding of no significant impact for a request from power company Entergy for exemptions related to storage of spent fuel at the shuttered Vermont Yankee nuclear power plant.
Following the Jan. 11 finding, the last step in the process is completion of a NRC staff safety review of the request, agency spokesman Neil Sheehan said by email Wednesday. “We anticipate that the safety review will be issued by the end of this month. The issuance of the safety review would represent the end of our review of the exemption request.”
In May 2017, Entergy requested a multipart exemption from a certificate of compliance for Holtec International’s HI-STORM 100 dry-cask system for spent nuclear reactor fuel, which is being used for on-site storage of Vermont Yankee’s used fuel assemblies following the plant’s December 2014 closure.
If the exemption is approved, Entergy would be authorized to employ an “optional regionalized loading pattern” for the multipurpose canisters used in the HI-STORM 100 system; load fuel cooled for no less than two years into the canister, rather than waiting for the otherwise mandatory three-year cooling period; and ready a per-cell maximum average burnup limit of 65,000 megawatt days per metric ton of uranium.
NRC staff found that the exemption would produce environmental effects “no greater” than those already cited in the regulator’s environmental assessment for the HI-STORM 100 system itself. They said a full environmental impact statement is not needed for the Entergy request.
“This change would allow the loading of fuel assemblies from the plant’s final operating cycle and thereby allow the completion of the transfer of all fuel from the spent fuel pool to dry cask storage by late 2018,” Sheehan said. “The exemption calls for the placement of older fuel on the periphery of the dry cask storage basket to act as shielding for the newer, hotter spent fuel.”
