ML14157A098
| ML14157A098 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 07/24/2014 |
| From: | Macfarlane A NRC/Chairman |
| To: | Boxer B, Markey E, Sanders B US Congress, US SEN (Senate), US SEN, Comm on Environment & Public Works |
| Rihm, Roger 415-1717 | |
| Shared Package | |
| ML14135A483 | List: |
| References | |
| CORR-14-0061, LTR-14-0282 | |
| Download: ML14157A098 (4) | |
Text
July 24, 2014 The Honorable Barbara Boxer Chairman, Committee on Environment and Public Works United States Senate Washington, DC 20510
Dear Madam Chairman:
On behalf of the U.S. Nuclear Regulatory Commission (NRC), I am responding to your letter of May 15, 2014, about the decommissioning of nuclear power plants. You raise concerns regarding the use of exemptions from emergency preparedness (EP) regulatory requirements, the movement of spent fuel to dry cask storage, and consideration of State and local government views in decommissioning planning.
I recently responded to a May 1, 2014, letter from you and your colleagues that also expressed concern regarding the use of exemptions for decommissioning facilities. In that letter, I provided some general information on the use of exemptions as part of NRCs regulatory process. The practice of considering exemptions is a well-established and important part of the NRCs regulatory process that allows licensees to address site-specific situations or implement alternative approaches for circumstances not necessarily contemplated in the regulations. As noted previously, the NRC will only grant an exemption request that is accompanied by a technical justification that the agency finds demonstrates adequate protection will be maintained if the exemption is granted.
With specific regard to EP, the NRCs regulations do not address that once a reactor permanently ceases operation, the consequences of emergency and security scenarios are reduced. The current practice for EP exemptions, when granted, is not to relieve the licensee of all EP requirements. Rather, the exemptions modify the licensees EP plans commensurate with the site-specific risks that are present for a permanently shutdown reactor during decommissioning. For EP exemptions, these generally relate to a reduction in radiological risk as spent fuel ages and the preclusion of accidents applicable to an operating reactor.
Decommissioning facilities continue to receive NRC oversight to verify compliance with all applicable regulatory requirements, and to verify that adequate safety and security will continue to be maintained.
Your letter also urges the NRC to require expedited transfer of spent fuel to dry cask storage. The Commission recently approved the staffs recommendation that no further generic assessments be pursued related to possible regulatory actions to require expedited transfer of spent fuel to dry cask storage. The Commissions decision was based on consideration of the staffs analysis that concluded that the expedited transfer of spent fuel to dry cask storage would provide only a minor or limited safety benefit, and that its expected implementation costs would not be warranted. However, the Commission did direct the staff to modify the regulatory analysis to address an alternate loading configuration and inform licensees of any added safety benefit in adopting this configuration. The NRC staff will also develop an information paper regarding the treatment of limited term operational vulnerabilities associated with the discharge of spent fuel from cores into pools. Finally, the Commission also directed the NRC staff to consider the pending National Academy of Sciences (NAS) findings and how they comport with further work on spent fuel pool management.
With regard to incorporating the views of State and local governments into decommissioning activities, under the Atomic Energy Act of 1954, as amended, the NRC has sole responsibility for regulating radiological health, safety, and security at commercial nuclear power plants. Our regulations provide opportunities for interested parties, including State and local governments, to communicate their views to the NRC and the licensee regarding radiological decommissioning. NRC regulations provide an opportunity to comment when a licensee submits the Post-Shutdown Decommissioning Activities Report (PSDAR) and a License Termination Plan (LTP), which is reviewed as a license amendment request. In addition, the NRC conducts public meetings in the vicinity of the facility following licensee submission of its PSDAR and LTP, and there is an opportunity for a hearing regarding the LTP.
We also strongly encourage licensees to continue the industry practice of communicating with States, local communities, and other interested parties by sponsoring community advisory groups.
States often play a significant role in nuclear facility decommissioning beyond the NRCs responsibility for radiological safety and security, particularly on matters relating to socio-economic impacts, including the funding of additional activities and State-specific remediation standards. For example, regarding a licensees decommissioning trust funds, the NRC has jurisdiction over a portion of these funds that are designated for radiological decommissioning of the nuclear facility. Recognizing that the decommissioning of power reactor sites may also be subject to regulation of non-radiological hazards by other Federal or State government agencies, it is incumbent upon the licensee to properly allocate funding for the entire decommissioning process, including both Federal and State requirements. Furthermore, it is imperative for the licensee to have an adequate and accurate reporting process in place to ensure that all regulatory bodies, Federal and State alike, are well informed of the status of a licensees financial ability to comply with regulatory requirements and to complete the various stages of decommissioning in a timely manner.
An additional matter discussed in your letter is the conditions that might lead to a spent fuel pool fire. Spent fuel pools are designed to prevent the rapid loss of water used to cool the spent fuel. A spent fuel pool loss of cooling event, such as an extended loss of power at the site, would evolve slowly due to the spent fuel pool design and the large volume of water in the pool. The water temperature would increase but continue to provide cooling to the spent fuel rods. In the unlikely event that no action is taken to provide supplemental cooling, damage to the spent fuel is possible if the water boils off sufficiently to uncover the spent fuel. According to recent calculations by the licensee that considered the age of its spent fuel and the volume of its spent fuel pools (enclosed), more than 15 days would be available to take mitigative actions to restore or maintain water levels after a loss of cooling event at San Onofre Nuclear Generating Station (SONGS). This gives licensee personnel sufficient time to implement plant procedures to restore cooling for the spent fuel. Licensees have measures in place to address this condition and to sustain the spent fuel cooling function. These measures include using equipment available onsite or obtaining offsite equipment, as needed. Equipment available onsite can vary based on the licensees site-specific plans and procedures, but generally includes large portable generators, pumps, and hoses.
Prior NRC studies acknowledge that fuel cladding could reach its ignition temperature given certain highly unlikely conditions that result in the draindown of the spent fuel pool. These studies are often based on conservative assumptions, such as no effective mitigative measures are taken. The studies also recognize that the scenarios that could result in such conditions have a very low probability of occurrence.
I appreciate hearing your views on these important topics. Please be assured that we give them serious consideration. If you need any additional information, please contact me or Amy Powell, Acting Director of the Office of Congressional Affairs, at (301) 415-1776.
Sincerely,
/RA/
Allison M. Macfarlane
Enclosure:
As stated cc: Senator David Vitter
Identical letter sent to:
The Honorable Barbara Boxer Chairman, Committee on Environment and Public Works United States Senate Washington, DC 20510 cc: Senator David Vitter The Honorable Bernard Sanders United States Senate Washington, DC 20510 The Honorable Edward J. Markey United States Senate Washington, DC 20510