ML15036A273
| ML15036A273 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 02/25/2015 |
| From: | Bill Dean Office of Nuclear Reactor Regulation |
| To: | Bryan Hanson Exelon Nuclear |
| Govan T, NRR/JLD, 415-6197 | |
| References | |
| TAC MF5648, TAC MF5649 | |
| Download: ML15036A273 (3) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Mr. Bryan C. Hanson President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555 February 25, 2015
SUBJECT:
PEACH BOTTOM ATOMIC POWER STATION, UNITS 2 AND 3 - RELAXATION OF RESPONSE DUE DATES REGARDING FLOODING HAZARD REEVALUATIONS FOR RECOMMENDATION 2.1 OF THE NEAR-TERM TASK FORCE REVIEW OF THE INSIGHTS FROM THE FUKUSHIMA DAl-ICHI ACCIDENT (TAC NOS. MF5648 AND MF5649)
Dear Mr. Hanson:
The purpose of this letter is to respond to your recent extension request to submit your Peach Bottom Atomic Power Station (PBAPS), Units 2 and 3 flooding hazard reevaluation report (FHRR). For background and content the Nuclear Regulatory Commission (NRC) considered the following information.
By letter dated March 12, 2012, 1 the NRC issued a request for information under Title 10 of the Code of Federal Regulations, Section 50.54(f) (hereafter referred to as the 50.54(f) letter). The agency issued the request as a part of implementing lessons-learned from the accident at the Fukushima Dai-ichi nuclear power plant. Enclosure 2 to the 50.54(f) letter requested licensees perform a reevaluation of external flooding hazards using present-day guidance and methodologies.
By letter dated May 11, 2012,2 the NRC issued a prioritization of due dates for all sites. For PBAPS, Units 2 and 3 the FHRR submission date was March 12, 2014.
By letter dated March 12, 2014,3 Exelon Generation Company, LLC (Exelon) requested a 1-year extension to the submittal schedule for the FHRR for PBAPS, Units 2 and 3 with a new due date of March 12, 2015. By letter dated July 17, 2014,4 the NRC issued a letter granting Exelon's request for a 1-year extension to the previously scheduled submittal date for the PBAPS Flooding Hazard Reevaultion Report.
By letter dated January 5, 2015,5 Exelon requested an additional extention of 5-months to the submittal schedule for the FHRR for PBAPS, Units 2 and 3 with a new due date of August 12, 2015. As justification for the request, Exelon stated that it would require additional 1 The 50.54(f) letter is available in the Agencywide Documents Access and Management System (ADAMS) under Accession No. ML12053A340.
2 The prioritization letter is available under ADAMS Accession No. ML12097A509.
3 The extension request from Exelon is available under ADAMS Accession No. ML14071A278.
4 The extension request granted from NRC is available under ADAMS Accession No. ML14174A879.
5 The extension request from Exelon is available under ADAMS Accession No. ML15006A239.
time to develop a detailed hydrologic model of the Susquehanna River watershed. In its letter, Exelon described a number of additional factors to justify the new schedule.
The NRC staff reviewed Exelon's justification and considered the following factors when reviewing the proposed new schedule:
PBAPS has completed calculations for the site drainage response to a Local Intense Precipitation event and the Rock Run Creek probable maximum flood (PMF), and determined these flood causing mechanisms do not pose a challenge to plant safety.
There are no required interim actions resulting from the completed calculations; The record flood of 1972 resulted in a flood level of 113.5 feet absent wave runup. The current licensing basis (CLB) for PBAPS is a postulated flood level of 132 feet and structures required for safe shutdown are protected to 135 feet; Exelon is developing a detailed hydrometerological study that will produce new extreme rainfall and snowmelt parameters specific to the Susquehanna River watershed for their Conowingo Hydroelectric Dam, located downstream of PBAPS. This study is being done for the Federal Energy Regulatory Commission and will be integrated into the PBAPS FHRR. Additional time is required to maintain alignment between the PBAPS and Conowingo PMF studies; and The limited duration of the proposed extension (5-months) and the facts that: 1) PBAPS has margin between the worst recorded flood level and its CLB flood level and the protection level for any safety related equipment, and 2) the analysis completed to date has not identified the need for any interim action supports the proposed extension.
Given these considerations, the NRC considers Exelon's proposed revised schedule to be acceptable. Accordingly, and based upon the authority granted to the Director of the NRC's Office of Nuclear Reactor Regulation, the required response date for submitting the FHRR for PBAPS is now August 12, 2015.
If you have any questions regarding this matter, or if it is necessary to revise the submittal schedule, please contact Robert Kuntz, at (301) 415-3733 or by e-mail at Robert.Kuntz@nrc.gov.
Sincerely, William M. Dean, Director Office of Nuclear Reactor Regulation Docket Nos. 50-277 and 50-278 cc: Listserv
- via email OFFICE NRR/JLD/JHMB/PM NRR/JLD/JHMB/PM*
NRR/JLD/LA NRR/DORl/LPL 1-2/PM NAME TGovan RKuntz Slent REnnis DATE 02/12/15 02/11/15 02/10/15 02/12/15 OFFICE NRR/JLD/JHMB/BC OGC NRR/JLD/D NRR/D NAME SWhaley BHarris JDavis (MFranovich for) WDean DATE 02/12/15 02/20/15 02/12/15 02/25/15