ML15343A418
| ML15343A418 | |
| Person / Time | |
|---|---|
| Site: | Farley  |
| Issue date: | 12/10/2015 |
| From: | Minarik A Japan Lessons-Learned Division |
| To: | Pierce C Southern Nuclear Operating Co |
| Minarik, Anthony NRR/JLD 415-6185 | |
| References | |
| TAC MF7039, TAC MF7040 | |
| Download: ML15343A418 (8) | |
Text
OFFICIAL USE ONLY SECURITY RELATED INFORMATION UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 December 10, 2015 Mr. C. R. Pierce, Regulatory Affairs Director Southern Nuclear Operating Co., Inc.
P.O. Box 1295, Bin 038 Birmingham, AL 35201-1295
SUBJECT:
JOSEPH M. FARLEY NUCLEAR PLANT, UNITS 1 AND 2 - INTERIM STAFF RESPONSE TO REEVALUATED FLOOD HAZARDS SUBMITTED IN RESPONSE TO 10 CFR 50.54(f) INFORMATION REQUEST-FLOOD-CAUSING MECHANISM REEVALUATION (TAC NOS. MF7039 AND MF7040)
Dear Mr. Pierce:
The purpose of this letter is to provide a summary of the U.S. Nuclear Regulatory Commission (NRC) staff's assessment of the re-evaluated flood-causing mechanisms described in the October 21, 2015 (Agencywide Documents Access and Management System (ADAMS)
Accession No. ML15294A530), flood hazard reevaluation report (FHRR) submitted by Southern Nuclear Operating Company, Inc. (SNC, the licensee) for Joseph M. Farley Nuclear Plant (Farley) Units 1 and 2, as well as supplemental information resulting from requests for additional information.
By letter dated March 12, 2012, the NRC issued a request for information pursuant to Title 10 of the Code of Federal F~egulations, Section 50.54(f) (hereafter referred to as the 50.54(f) letter)
(ADAMS Accession No. ML12053A340). The request was issued as 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 to re-evaluate flood-causing mechanisms using present-day methodologies and guidance. Concurrently, with the reevaluation of flooding hazards, licensees were required to develop and implement mitigating strategies in accordance with NRC Order EA-12-049, "Requirements for Mitigation Strategies for Beyond-Design-Basis External Events" (ADAMS Accession No. ML12054A735). On March 30, 2015, the Commission provided Staff Requirements Memoranda (SRM) (ADAMS Accession No. ML15089A236) to COMSECY-14-0037, "Integration of Mitigating Strategies for Beyond-Design-Basis External Events and the Reevaluation of Flooding Hazards," dated November 21, 2014 (ADAMS Accession No. ML14309A256), affirming that licensees need to address the reevaluated flooding hazards within their mitigating strategies for beyond-design-basis external events.
Enclosure two transmitted herewith contains Security-Related Information. When separated from the Enclosure, this document is decontrolled.
OFFICIAL USE ONLY SECURITY RELATED INFORMATION
OFFICIAL USE ONLY SECURITY RELATED INFORMATION The NRC staff has reviewed the information submitted by the licensee and has summarized the results of the review in the tables provided as Enclosure 1 to this letter. Table 1 provides the current design-basis flood hazard mechanisms. Table 2 provides reevaluated flood hazard mechanisms; however, reevaluated hazard mechanisms bounded by the current design-basis (Table 1) are not included. Because Table 2 includes security-related information, Enclosure 1 contains the redacted version of Table 2. Enclosure 2 is withheld from public disclosure and restores the security-related information to Table 2.
The NRC staff has concluded that the licensee's reevaluated flood hazards information, as summarized in the Enclosure, is suitable for the assessment of mitigating strategies developed in response to Order EA-12-049 (i.e., defines the mitigating strategies flood hazard information described in guidance documents currently being finalized by the industry and NRC staff) for Farley. Further, the NRC staff has concluded that the licensee's reevaluated flood hazard information is a suitable input for other assessments associated with Near-Term Task Force Recommendation 2.1 "Flooding." The NRC staff plans to issue a staff assessment documenting the basis for these conclusions at a later time.
In addition, Nuclear Energy Institute (NEI) guidance document NEI 12-06 "Diverse and Flexible Coping Strategies (FLEX) Implementation Guide" is currently being revised. This revision will include a methodology to perform a Mitigating Strategies Assessment (MSA) with respect to the reevaluated flood hazards. Once this methodology is endorsed by the NRC, flood event duration parameters and applicable flood associated effects should be considered as part of the Farley MSA. The NRC staff will evaluate the flood event duration parameters (including warning time and period of inundation) and flood-related associated effects developed by the licensee during the NRC staff's review of the MSA.
As stated above, Table 2 of the enclosure to this letter describes the reevaluated flood hazards that exceed the current design-basis. In order to complete its response to the information requested by Enclosure 2 to the 50.54(f) letter, the licensee is expected to submit an integrated assessment or a focused evaluation, as appropriate, to address these reevaluated flood hazards, as described in the NRC letter, "Coordination of Request for Information Regarding Flooding Hazard Reevaluation and Mitigating Strategies for Beyond-Design-Basis External Events" (ADAMS Accession No. ML15174A257). This letter describes the changes in the NRC's approach to the flood hazard reevaluations that were approved by the Commission in its SRM to COMSECY-15-0019, "Closure Plan for the Reevaluation of Flooding Hazards for Operating Nuclear Power Plants" (ADAMS Accession No. ML15209A682).
OFFICIAL USE ONLY SECURITY RELATED INFORMATION
OFFICIAL USE ONLY SECURITY RELATED INFORMATION If you have any questions, please contact me at (301) 415-6185 or e-mail at Anthony.Minarik@nrc.gov.
Docket Nos. 50-348 and 50-364 Enclosures
- 1.
Summary of Results of Flooding Sincerely,
- ~
Anthony Minarik, Proj anager Hazards Management Branch Japan Lessons-Learned Division Office of Nuclear Reactor Regulation Hazard Re-Evaluation Report (Redacted Version)
- 2.
Summary of Results of Flooding Hazard Re-Evaluation Report (Non-Public Version) cc w/encl: Distribution via Listserv OFFICIAL USE ONLY SECURITY RELATED INFORMATION
ENCLOSURE 1:
SUMMARY
TABLES OF REEVALUATED FLOOD HAZARD LEVELS
Joseph M. Farley Nuclear Plant, Units 1 & 2 Table 1. Current Design Basis Flood Hazards for Use in the MSA Mechanism Local Intense Precipitation Outside Turbine Building i
I Streams and Rivers I Chattahooche River Failure of Dams and Onsite Water Control/Storage Structures
[Redacted]
[Redacted]
[Redacted]
[Redacted]
[Redacted]
Storm Surge I Seiche I
Stillwater Elevation 6.0 inch depth 144.2 ft NGVD29
[Redacted]
[Redacted]
[Redacted]
[Redacted]
[Redacted]
No Impact on the Site Identified No Impact on the Site Identified I
I I
i i
I I
Waves/
Runup Minimal 9.1 ft (Redacted]
[Redacted]
[Redacted]
[Redacted]
[Redacted]
No Impact on the Site Identified No Impact on the Site Identified Design Basis Hazard Elevation 6.0 inch depth 153.3ft NGVD29
[Redacted]
[Redacted]
[Redacted]
[Redacted]
[Redacted]
No Impact on the Site Identified No Impact on the Site Identified Reference FHRR 3.b.1 and Table 5-1 FHRR Section 3.b.2, Section 3.b.8, and Table 5-1
[Redacted]
[Redacted]
[Redacted]
[Redacted]
[Redacted]
FHRR Section 3.b.5 and Table 5.1 FHRR Section 3.b.5 and Table 5-1
Joseph M. Farley Nuclear Plant, Units 1 & 2 Table 1. Current Design Basis Flood Hazards for Use in the MSA Mechanism Stillwater Waves/
Design Basis Reference Elevation Run up Hazard Elevation Tsunami No Impact i No Impact No Impact FHRR Section 3.b.5 and Table 5-1 on the Site on the Site on the Site Identified Identified Identified I
Ice-Induced Flooding No Impact No Impact No Impact FHRR Section 3.b.6 and Table 5-1 on the Site I
on the Site on the Site Identified i
Identified Identified I
I I
Channel Migrations/Diversions I
No Impact No Impact No Impact FHRR 3.b.7 and Table 5-1 on the Site on the Site on the Site I
Identified Identified Identified I
I i
I __
Note 1: Reported values are rounded to the nearest one-tenth of a foot.
I Joseph M. Farley Nuclear Plant, Units 1 & 2 Table 2. Reevaluated Flood Hazards for Flood-Causing Mechanisms for Use in the MSA Mechanism Local Intense Precipitation Auxiliary Unit 1 Auxiliary Unit 2 Containment Unit 1 Containment Unit 2 Diesel Generator Building Service Water Intake Structure Failure of Dams and Onsite Water Control/Storage Structures
[Redacted]
[Redacted]
I I
I i
Stillwater Elevation 155.8 ft NGVD29 155.8 ft NGVD29 155.2 ft NGVD29 156.0 ft NGVD29 155.4 ft NGVD29 195.8 ft NGVD29
[Redacted]
I
[Redacted]
I I
Waves/
Run up I
Minimal Minimal Minimal Minimal Minimal Minimal
[Redacted)
Reevaluated Hazard Elevation 155.8 ft NGVD29 155.8 ft NGVD29 155.2 ft NGVD29 156.0 ft NGVD29 155.4 ft NGVD29 195.8 ft NGVD29
[Redacted]
[Redacted)
[Redacted)
I Reference FHRR Tables 4-1 and 5-1 FHRR Tables 4-1 and 5-1 FHRR Tables 4-1 and 5-1 FHRR Tables 4-1 and 5-1 FHRR Tables 4-1 and 5-1 FHRR Tables 4-1 and 5-1 I
[Redacted]
[Redacted)
Note 1: The licensee is expected to develop flood event duration parameters and applicable flood associated effects to conduct the MSA. The staff will evaluate the flood event duration parameters (including warning time and period of inundation) and flood associated effects during its review of the MSA.
Note 2: Reevaluated hazard mechanisms bounded by the current design basis (see Table 1) are not included in this table Note 3: Reported values are rounded to the nearest one-tenth of a foot.
I I
I I
PKG ML15343A379 LTR: ML15343A418 ENCL 1: ML15338A296 ENCL2: ML15338A292
- via email OFFICE NRR/JLD/JHMB/PM NRR/JLD/LA NRO/DSEA/RHM2/TR*
NAME AMinarik Slent KSee DATE 12/7/15 12/10/2015 12/7/15 OFFICE NRO/DSEA/RHM2/BC*
NRR/JLD/JHMB/BC NRR/JLD/JHMB/PM NAME CCook MShams AMinarik DATE 12/7/15 12/10/2015 12/10/2015