The Zion nuclear plant site as it appeared earlier this year. (Photo: Tim Gregoire)
The Nuclear Regulatory Commission has released for “unrestricted use” most of the land on and around where the Zion nuclear power plant once operated in northeastern Illinois. This means that any residual radiation is below the NRC’s limits and there will be no further regulatory controls by the agency for that portion of the property.
Only the plant’s independent spent fuel storage installation (ISFSI), which covers about 5 acres, will remain under NRC license and oversight.
Some history: The Zion plant consisted of two pressurized water reactors that operated from 1973 until 1997. Then-operator Commonwealth Edison certified the permanent shutdown of the plant in 1998.
In 2010, Zion’s licenses were transferred from Exelon Generation (now Constellation Energy) to ZionSolutions, a subsidiary of radioactive waste disposal company EnergySolutions, to expedite the decommissioning process.
Final surveys: ZionSolutions completed the majority of Zion’s decommissioning work by 2019, and the NRC approved the transfer of Zion’s licenses back to Constellation that same year, conditional on the satisfactory completion of the site’s final status surveys.
Radioactive contamination was found at the site, however, requiring additional remediation and delaying the final status survey reviews. It was found that the particles were released from Zion’s containment buildings and fuel handling building during decommissioning work.
On November 8, the NRC informed ZionSolutions that it had completed its review of the survey reports and found that they provide “reasonable assurance” that the residual radioactivity at the site met the agency’s radiation protection standards.
Next steps: ZionSolutions is now free to transfer Zion’s ISFSI license to Constellation, which will be responsible for the security and protection of the spent fuel until an off-site storage facility or permanent disposal site becomes available.
Once the two companies close on their transaction, the NRC will issue amendments changing the name on the license to Constellation, which is then free to use the remainder of the former plant site for any application.