ONS-2016-068, Seventh Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond Design-Basis External Events (Order Number EA-12-049)
ML16250A019 | |
Person / Time | |
---|---|
Site: | Oconee ![]() |
Issue date: | 08/26/2016 |
From: | Batson S Duke Energy Carolinas |
To: | Document Control Desk, Office of Nuclear Reactor Regulation |
References | |
EA-12-049, ONS-2016-068 | |
Download: ML16250A019 (19) | |
Text
Scott L. Batson
(-,DUKE
~ ENERGY Vice President Oconee Nuclear Station Duke Energy ON01VP I 7800 Rochester Hwy Seneca, SC 29672 ONS-2016-068 o: 864.873.3274
- t. 864.873.4208 Scott.Batson@duke-energy.com August 26, 2016 10 CFR 50.4 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington; DC 20555 Duke Energy Carolina, LLC (Duke Energy)
Oconee Nuclear Station, Units 1, 2 and 3 Docket Numbers 50-269, 50-270, 50-287 Renewed License Numbers DPR-38, DPR-47, and DPR-55
Subject:
Seventh Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049)
- _
References:
- 1. Nuclear Regulatory Commission (NRC) Order Number EA-12-049, Order Modifying Licensees With Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, dated March 12, 2012 (Accession No. ML12054A735).
- 2. Oconee Nuclear Station's Overall Integrated Plan in Response to March 12, 2012, Commission Order to Modify Licenses With Regard To Requirements for Mitigatiori Strategies for Beyond-Design-Basis External Events (Order EA-12-049), dated February 28, 2013 (Accession No. ML13063A065).
- 3. Oconee Nuclear Station's First Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses With Regard to Requirements for Mitigation Strategies for Beyond-Design-basis External Events (Order Number EA-12-049), dated August 29, 2013 (Accession No. ML13246A009).
- 4. Oconee Nuclear Station's Second Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses With Regard to Requirements for Mitigation Strategies for Beyond-Design-basis External Events (Order Number EA-12-049), dated February 28, 2014 (Accession No. ML14064A197).
- 5. Oconee Nuclear Station's Third Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses With Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number'EA-12-049), dated August 27, 2014 (Accession No. ML14245A018).
- 6. Oconee Nuclear Station's Fourth Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) dated February 27, 2015 (Accession No. ML15063A027).
- 7. Oconee Nuclear Station's Fifth Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) dated August 26, 2015 (Accession No. ML15247A068).
ONS-2016-068 August 26, 2016 Page 2
- 8. Oconee Nuclear Station's Sixth Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) dated February 29, 2016 (Accession No. ML16064A091 ).
- 9. NEI 12-06, [Rev. O], Diverse and Flexible Coping Strategies (FLEX) Implementation Guide, dated August 2012 (Accession No. ML12242A378).
Ladies and Gentlemen, On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued Order EA-12-049 (Reference 1) to Duke Energy which was immediately effective and directed Duke Energy to develop guidance and strategies to maintain or restore core cooling, containment, and spent fuel pool cooling capabilities in the event of a beyond-design-basis external event. The Order required that, following NRC's issuance of its final Interim Staff Guidance (ISG), Duke Energy would submit an Overall Integrated Plan (OIP), followed by status reports at six-month intervals.
Duke Energy has thus far submitted the OIP (Reference 2), and six six-month reports (References 3 to 8) for Oconee Nuclear Station. The purpose of this letter is to provide the seventh six-month status report. The enclosure provides updates related to compliance with NRC Order EA-12-049 and Nuclear Energy Institute (NEI) 12-06 (Reference 9) during the January 29, 2016 to July 28, 2016 update period.
This letter contains no new or revised Regulatory Commitments.
Should you have any questions regarding this submittal, please contact David Haile with Oconee Regulatory Affairs, at (864) 873-4742.
I declare under penalty of perjury that the foregoing is true and correct. Executed on August 26, 2016.
Sincerely, dl1~
Scott L. Batson Vice President Oconee Nuclear Station
Enclosure:
Units 1, 2, and 3
ONS-2016-068 August 26, 2016 Page 3 cc:
Ms. Catherine Haney, Regional Administrator U.S. Nuclear Regulatory Commission - Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, Georgia 30303-1257 Mr. William Dean, Director, Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 Mr. James R. Hall, Project Manager (ONS)
(by electronic mail only)
U.S. Nuclear Regulatory Commission 11555 Rockville Pike, M/S 0-8G9A Rockville, MD 20852-27 46 Mr. Eddy Crowe NRC Senior Resident Inspector Oconee NuclearStation
- ONS-2016-068 August 26, 2016 Page 4 bxc:
T.P. Gillespie (ECO?H)
T.D. Ray (ON01VP)
J. E Burchfield (ON01VP)
C.T. Dunton (ON01VP)
D. M. Hubbard (ON01VP)
D. C. Jones (ON01 El)
C.J. Wasik (ON03RC)
D.C. Haile (ON03RC)
L. F. Todd (ON03RC)
M.C. Nolan (EC05P)
C.J. Thomas (EC01T)
G.D. Robison (EC09E)
B. M. Thomas (ON01 El)
P. F. Guill (EC01T)
ONS Master File (ON02DM, File OS 801.01)
ELL (EC2ZF)
ENCLOSURE 1 Oconee Nuclear Station (ONS)
Seventh Six Month Status Report for Order EA-12-049 (FLEX),
Units 1, 2, and 3 Encl. Page 1 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
- 1) Introduction On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued Order EA-12-049 (Reference E1) to Duke Energy which required the development of guidance and strategies related to mitigation of a beyond-design-basis external event. The Order required each plant to issue an Overall Integrated Plan (OIP) pursuant to the NRC's Interim Staff Guidance (ISG)
(Reference E2) which endorsed, with clarifications and exceptions, the industry guidance document, NEI 12-06 (Reference E3). The Order also required that update reports on progress or change to the OIP be submitted every six months.
An Overall Integrated Plan (Reference E4) was developed based on the diverse and flexible strategies (FLEX) from NEI 12-06 in response to NRC Order EA-12-049 and was submitted to the NRC on February 28, 2013. Six six-month updates have subsequently been submitted to the NRC (Refer~nces E5, E18, E28, E29, E30, and E38).
This report constitutes the seventh six-month update, and reports milestone accomplishments, changes to the compliance method or schedule, or any need for relief/relaxation, and the basis, which occurred during the period from January 29, 2016 to July 28, 2016 (hereafter referred to as "the update period").
- 2) Milestone Accomplishments (during the update period)
The following milestone(s) were completed:
- 1. The sixth six-month status report was submitted February 29, 2016.
- 2. Unit 3 Implementation and )mplementation Walkdowns were completed.
- 3. Unit 3 is considered in compliance with NRC Order EA-12-049 as of May 15th, 2016 (Reference E39).
- 3) Milestone Schedule Status The following represents the milestone status at the end of the update period. The table reflects updates to the milestone table in Attachment 2 of the Overall Integrated Plan. It provides the status of each activity, and whether the target completion date has changed.
Note: The dates are planning dates, and are subject to change as design and implementation details are-developed. Revised target completion dates are not expected to impact the implementation date(s) of the Order.
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Submit Overall Integrated Plan Feb 2013 Complete Date Not Revised Submit 6 Month Update 1 Aug2013 Complete Date Not Revised Submit 6 Month Update 2 Feb 2014 Complete Date Not Revised Submit 6 Month Update 3 Aug 2014 Complete Date Not Revised Submit 6 Month Update 4 Feb 2015 Complete Date Not Revised Submit 6 Month Update 5 Aug2015 Complete Date Not Revised Submit 6 Month Update 6 Feb 2016 Complete Date Not Revised Submit 6 Month Update 7 Aug2016 This Submittal Date Not Revised Encl. Page - 2 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
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Develop Modifications Aug2016 Complete Date Not Revised
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Identify Significant Material/Equipment Sept 2013 Complete Date Not Revised Material/Equipment August Complete Date Not Revised Procurement/Delivery 2016
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Conduct N-1 Outage Walkdowns- Ul Nov2014 Complete Date Not Revised Conduct N-1 Outage Walkdowns - U2 Nov 2013 Complete Date Not Revised Conduct N-1 Outage Walkdowns- U3 May2014 Complete Date Not Revised Conduct Implementation Walkdowns- Ul Oct 2016 Started Date Not Revised Conduct Implementation W alkdowns - U2 Oct 2015 Complete Date Not Revised Conduct Implementation Walkdowns- U3 April 2016 Complete Date Not Revised
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Develop Training program - Ul July 2016 Complete Date Not Revised Develop Training program - U2 July 2015 Complete Date Not Revised Develop Training program - U3 April 2016 Complete Date Not Revised Implement Training - Ul Oct 2016 Started Date Not Revised Implement Training - U2 Oct 2015 Complete Date Not Revised Implement Training - U3 April 2016 Complete Date Not Revised
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Develop FLEX Guidelines (FGs) June 2016 Complete Date Not Revised Develop Maintenance Procedures June 2016 Complete Date Not Revised Develop Strategies/Playbook with RRC April 2015 Complete Date Not Revised Install Offsite Delivery Pad March 2015 Complete August 2015 (Installation not required)
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Implement Modifications - Ul Nov2016 Started Date Not Revised Implement Modifications - U2 Nov2015 Complete Date Not Revised Implement Modifications - U3 May 2016 Complete Date Not Revised Encl. Page - 3 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
- 4) Changes to Compliance Method No changes to compliance method that are alternatives to NEI 12-06 Rev. 0 were made during the update period.
Provided on the Fifth Six-Month Status Report (Reference E30):
During the July 2015 NRG Onsite Audit, it was discussed that the Atmospheric Dump Valves (ADVs) are rugged but not located in a structure protected from all beyond design-basis external events. Therefore, the NRG Auditors' perspective was that crediting ADV operation should be considered an alternate approach to NE/ 12-06. Oconee acknowledges this position. Justification is provided in OSG-11383 Attachment 10 (Reference E25) with respect to why the use of the ADVs is acceptable.
- 5) Need for Relief and Basis for the Relief Duke Energy Carolinas, LLC (Duke Energy), Oconee Nuclear Station, Units 1, 2, and 3 anticipates meeting the Order implementation date and no relief is required at this time.
- 6) Open Items from Overall Integrated Plan and Draft Safety Evaluation
'
The following tables provide a summary status of the Open Items. The table Section 6.a.
provides the open items identified in the original OIP submitted on February 28, 2013. The table Section 6.b. provides a list of open items that were added after February 28, 2013 through the end of the update period. The table Section 6.c. provides a list of open and confirmatory items related to the Interim Staff Evaluation (ISE) (Reference E19). The table Section 6.d.
addresses any generic concerns (No new generic issues were identified during this update period).
a) Open Items Documented in the Overall Integrated Plan
.. Overall Jntegr~te_d ~tan Op:en Items
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Completed (References E32 and E33)
Analysis approved by the NRC.
Closed during NRC July 2015 Audit.
Completed (Reference E32)
Modifications do not impact flooding levels in
- 2. Max flood level on site 'after modifications' approved analysis.
Tracked by ONS NTM 01935875-02.
Closed during NRC July 2015 Audit.
Completed for Unit 2 and Unit 3 (Reference E37 - U2 & U3 Compliance Matrices)
- 3. Deployment Path Program Tracked by ONS NTM 01935875-03.
On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Completed for Unit 2 and Unit 3 (Reference E37 - U2 & U3 Compliance Matrices)
On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Completed for Unit 2 and Unit 3 Tracked by ONS NTM 01935875-05.
- 5. FLEX Equipment Programmatic Control On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Encl. Page - 4 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
- i:;::;'{.<?~ir~!l)V'.i~gt:~1~~d:J!i~~i~2~~~ ,'.f,!~m.~ *~.::};~ ,..:r'i[is;\{.:t:*/'.'.r~:, * * **'*;.;.}* ,, *i; 7:*:*,;,~:~*r:N{:*
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Completed for Unit 2 and Unit 3 (Reference E37 - U2 & U3 Compliance Matrices)
- 6. Personnel Training Tracked by ONS NTM 01935875-06.
On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Completed for Unit 2 and Unit 3 (Reference E34)
(Reference E3 7 - U2 & U3 Compliance Matrices)
On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Completed for Unit 2 and Unit 3 (Reference E3 7 - U2 & U3 Compliance Matrices)
- 8. Configuration Control Tracked by ONS NTM 01935875-08.
On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Completed (Reference E35)
Closed during NRC July 2015 Audit.
Initial analyses complete. Additional cases are being incorporated.
- 10. Cooldown Analysis Tracked by ONS NTM 01935875-10.
Closed during NRC July 2015 Audit.
Completed (Reference E37 - U2 & U3 Compliance Matrices)
- 11. ADV Survivability and Accessibility Tracked by ONS NTM 01935875-11.
Closed during NRC July 2015 Audit.
Completed (Reference E25, Att. 3)
- 12. Load Shed Analysis Tracked by ONS NTM 01935875-12.
Closed during NRC July 2015 Audit.
Completed (Reference E22)
- 13. Hydraulic Analysis for Pump Flow (Intake Analysis results are acceptable. Tracked by ONS Canal to SGs) NTM 01935875-13.
Closed during NRC July 2015 Audit.
Completed (Reference E25, Att. 4)
- 14. Fuel Oil Consumption Tracked by ONS NTM 01935875-14.
Closed during NRC July 2015 Audit.
Completed (Reference E22)
- 15. Hydraulic Analysis for Pump Flow (CTP-1 to Analysis results are acceptable.
SGs) Tracked by ONS NTM 01935875-15.
Closed during NRC July 2015 Audit.
Completed (Reference E26)
Analysis for Pumping Configuration Closed during NRC July 2015 Audit.
Completed
Closed during NRC July 2015 Audit.
Completed (Reference E23)
(SG Makeup)
Closed during NRC July 2015 Audit.
Encl. Page - 5 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
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- Q~efall Integ~~~ed Plan .Op~h*items : " , Status:. * :
- Completed for all units
Closed during NRC July 2015 Audit.
Completed for Unit 2 and Unit 3 (Reference E37 - U2 & U3 Compliance Matrices)
- 20. fustrumentation Repower Tracked by ONS NTM 01935875-20.
(Alternate Repower Strategy)
On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Completed (Reference E36)
Closed during NRC July 2015 Audit.
Completed for Unit 2 and Unit 3 (Reference E3 7 - U2 & U3 Compliance Matrices)
- 22. Portable Power Distribution Tracked by ONS NTM 01935875-22.
(Primary Repower Strategy)
On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Completed (Reference E3 7 - U2 & U3 Compliance Matrices)
Closed during NRC July 2015 Audit.
Completed (Reference E27: Sect. 3.14 and Att. E)
Closed during NRC July 2015 Audit.
Completed for Unit 2 and Unit 3 (Reference E37 - U2 & U3 Compliance Matrices)
Makeup)
On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Completed (Reference E37 - U2 & U3 Compliance Matrices)
- 26. Containment Analysis Tracked by ONS NTM 01935875.:.26.
Closed during NRC July 2015 Audit.
Completed
- 27. Hydraulic Analysis for Pump Flow (CTP-1 to (Reference E37 - U2 & U3 Compliance Matrices)
SFPs & futake Canal to SFPs) Tracked by ONS NTM 01935875-27.
" Closed during NRC July 2015 Audit.
Completed (References E6 & E7)
Validated SFP Refill Lines are installed as QA-1
- 28. Robustness of SFP Refill Lines and are seismically robust.
Tracked by ONS NTM 01935875-28.
Closed during NRC July 2015 Audit.
Completed (Reference E37 - U2 & U3 Compliance Matrices)
- 29. Lighting Evaluation Tracked by ONS NTM 01935875-29.
Closed during NRC July 2015 Audit.
Completed (Reference E3 7 - U2 & U3 Compliance Matrices)
- 30. Communication Assessment Tracked by ONS NTM 01935875-30.
Closed during NRC July 2015 Audit.
Encl. Page - 6 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
Completed
- 31. NEI 12-01 Staffing Study (Reference E37 - U2 & U3 Compliance Matrices)
(Reference E24) Tracked by ONS NTM 01935875-31.
Closed during NRC July 2015 Audit.
Completed (Reference E3 7 - U2 & U3 Compliance Matrices)
Closed during NRC July 2015 Audit.
b) Open Items added after February 28th, 2013
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- 33. Evaluate changes to the RCSMU FLEX Strategy recommended by independent audit to eliminate Completed (Reference E25 Att. 2) the SSF RCMUP repower strategy and implement Tracked by ONS NTM 01935875-33.
train specific diesel powered pump strategies Closed during NRC July 2015 Audit.
(primary and alternate).
- 34. Evaluate changing the alternate repower FLEX Completed for Unit 2 and Unit 3 strategy to enhance deployment times by utilizing (Reference E3 7 - U2 & U3 Compliance a small 120 VAC portable diesel generator Matrices)
(approximately 6000 watts) deployed on the Tracked by ONS NTM 01935875-34.
Turbine Building deck to provide 120 V AC feeds On track for Unit 1 implementation.
to connections in the control room and cable room Closed during NRC July 2015 Audit.
to repower the key instrumentation parameters.
- 35. Validate the 10' assumed inundation level discussed in the OIP [Assumption #8] is still This item superseded by Open Item 40 conservative with respect to the Defense in Depth Tracked by ONS NTM 01935875-35.
Modifications analyzed in OIP Reference 48 Closed during NRC July 2015 Audit.
(which used a slightly modified model run) and the credited CAL model run in OIP reference 14.
- 36. Perform raw water fouling analysis for core Completed cooling and heat removal. (Reference E3 7 - U2 & U3 Compliance Matrices)
Tracked by ONS NTM 01935875-36.
Closed during NRC July 2015 Audit.
- 37. Evaluate freeze protection requirements in areas Completed of the plant that contain equipment used in FLEX (Reference E37 - U2 & U3 Compliance strategies. Matrices)
Tracked by ONS NTM 01935875-37.
Closed during NRC July 2015 Audit.
- 38. Evaluate and establish a technical basis for use of Completed non-safety related, installed equipment credited (Reference E37 - U2 & U3 Compliance for mitigating an ELAP event. . Matrices)
Tracked by ONS NTM 01935875-38.
Closed during NRC July 2015 Audit.
- 39. FLEX Strategy for Shutdown Modes: Determine Completed for Unit 2 and Unit 3 what mods, procedures, equipment, etc. is needed (Reference E3 7 - U2 & U3 Compliance to support a Shutdown Modes FLEX Strategy. Matrices)
Tracked by ONS NTM 01935875-39.
On track for Unit 1 implementation.
Closed during NRC July 2015 Audit.
Encl. Page - 7 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
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- 40. Clarification of Applicable External Flooding Completed Hazard at ONS. (Reference E3 7 - U2 & U3 Compliance Matrices)
Tracked by ONS NTM 01935875-40.
Closed during NRC July 2015 Audit.
c) Interim Staff Evaluation (ISE)
"' I.
.. ISE Open Itel1ls Status I. Provide a description and justification for the specific Open evaluation model(s) used in the ELAP analyses for (Reference E31 - U2 Compliance Letter)
Oconee (ISE Open Item# 3.2.1.1.A). (Reference E39 - U3 Compliance Letter)
Tracked by ONS NTM 01938086-02.
- 2. The licensee should either (1) develop a successful mitigating strategy that does not rely on repowering the SSF RCMU pumps following recession of floodwaters or Completed (Reference E25 Att. 2)
(2) provide adequate justification that the SSF RCMU Closed during NRC July 2015 Audit.
pumps can reliably be repowered following recession of floodwaters (ISE Open Item# 3 .2.1.6.A).
- 3. Provide adequate basis that nitrogen from the core flood Completed tanks will not be injected into the reactor coolant system (Reference E3 7 - U2 & U3 Compliance (ISE Open Item# 3.2.1.6.B). Matrices)
Closed during NRC July 2015 Audit.
- 4. When further analyses are completed, the licensee should Open provide additional information that either supports a (Reference E31 - U2 Compliance Letter) conclusion that pressurizer relief or safety valves do not (Reference E39 - U3 Compliance Letter) lift during the ELAP event or that lifting of the valve(s), if Tracked by ONS NTM 01938086-03.
it occurs, is acceptable (ISE Open Item# 3.2.1.6.C). Tracked by ONS NTM 02027807-02.
- 5. Provide additional information demonstrating successful Open mitigation of an ELAP event involving an uncontrolled (Reference E31 - U2 Compliance Letter) cooldown resulting from consequential damage to the (Reference E39 - U3 Compliance Letter) main steam system due to the severe natural hazard that Tracked by ONS NTM 01938086-04.
initiates the ELAP event (ISE Open Item# 3.2.1.6.D). Tracked by ONS NTM 02027807-03.
- 6. Demonstrate that Oconee's approach for modeling boric acid mixing is consistent with a generically acceptable Completed methodology or develop a plant-specific technical basis to (Reference E3 7 - U2 & U3 Compliance support the modeling assumptions for boric acid mixing in Matrices) the ELAP analysis for Oconee Closed during NRC July 2015 Audit.
(ISE Open Item# 3.2.1.8.B).
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'1s:E Con:tlrmatory items_
- stattis * '.
I. Confirm that ONS's final FLEX equipment deployment Completed routes include adequate consideration of potential soil (Reference E3 7 - U2 & U3 Compliance liquefaction or other conditions that could impede Matrices) movement following a severe seismic or other BOB Closed during NRC July 2015 Audit.
event (Confirmatory Item# 3.1.1.2.A).
- 2. Confirm that the licensee's reference source providing Completed guidance for operators to obtain instrument readings (Reference E3 7 - U2 & U3 Compliance under ELAP conditions adequately addresses the Matrices) considerations in NEI 12-06, Section 5.3.3, consideration Closed during NRC July 2015 Audit.
(1) (Confirmatory Item# 3.1.1.3.A).
Encl. Page - 8 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
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iSE Confirmatory Items .Status
- 3. Confirm that the details for delivery and staging of off- Completed site resources in the licensee's RRC playbook developed (Reference E37 - U2 & U3 Compliance by the SAFER team and the utility are acceptable for all Matrices)
BDBEEs (Confirmatory Item# 3.1.1.4.A). Closed during NRC July 2015 Audit.
- 4. To show conformity with NEI 12-06, Section 6.2.3.2, Completed consideration 2, confirm that persistent, prohibitive (Reference E3 7 - U2 & U3 Compliance flooding levels will not occur at the ONS site Matrices)
(Confirmatory Item# 3.1.2.2.A). Closed during NRC July 2015 Audit.
- 5. Confirm that the final ELAP computer code analyses for Open core cooling, reactor coolant system inventory, shutdown (Reference E3 l - U2 Compliance Letter) margin, and containment integrity have acceptable (Reference E39 - U3 Compliance Letter) methodology and assumptions and support the sequence Tracked by ONS NTM 01938086-05.
of events timeline (Confirmatory Item# 3.2.1.1.B).
- 6. Reliance on the RELAP5/MOD2- Babcock & Wilcox (B&W) and RETRAN-30 codes in the ELAP analysis for Completed B&W plants should be limited at the present time to the (Reference E3 7 - U2 & U3 Compliance flow conditions prior to boiler-condenser cooling Matrices) initiation. Confirm that the code is not used outside this Closed during NRC July 2015 Audit.
range (Confirmatory Item # 3 .2.1.1. C).
- 7. Confirm the means of isolating RCP seal return and RCS Completed letdown in accordance with the Jocassee dam break (Reference E37 - U2 & U3 Compliance procedure and the associated timeframe Matrices)
(Confirmatory Item# 3.2.1.2.A). Closed during NRC July 2015 Audit.
- 8. Confirm that RCP seal temperature would be maintained Open at an acceptably low value by establishing injection flow (Reference E3 l - U2 Compliance Letter) to the RCP seals via the SSF RCMU pump within 20 (Reference E39 - U3 Compliance Letter) minutes of event initiation (Confirmatory Item# Tracked by ONS NTM 01938086-06.
3 .2.1.2.B). Tracked by ONS NTM 02027807-04.
- 9. Confirm there is justification for the assumed seal Open leakage rates for the Bingham RCPs with Sulzer seal (Reference E31 - U2 Compliance Letter) assemblies (Confirmatory Item# 3.2.1.2.C). (Reference E39 - U3 Compliance Letter)
Tracked by ONS NTM 01938086-07.
Tracked by ONS NTM 02027807-04.
- 10. Confirm there is justification for the assumed seal Open leakage rates for the Westinghouse 93-A RCPs with (Reference E31 - U2 Compliance Letter)
Flowserve N-9000 seals with the Abeyance feature (Reference E39 - U3 Compliance Letter)
(Confirmatory Item# 3.2.1.2.D). Tracked by ONS NTM 01938086-08.
- 11. Confirm that steam generator pressure indication will be available to support the cooldown directed by the ELAP Completed mitigating strategy, or provide adequate basis that such (Reference E3 7 - U2 & U3 Compliance indication is unnecessary even at average reactor coolant Matrices) temperatures below 525 degrees Fahrenheit Closed during NRC July 2015 Audit.
(Confirmatory Item# 3.2.1.5.A).
- 12. Confirm that the final containment analysis (open item Completed
- 26) demonstrates that there will be no impact on the (Reference E37 - U2 & U3 Compliance credited instrumentation (Confirmatory Item# 3.2.1.5.B). Matrices)
Closed during NRC July 2015 Audit.
- 13. When evaluations are completed, confirm that the Open survivability and performance of the atmospheric dump (Reference E3 l - U2 Compliance Letter) valves is adequate to support ONS's mitigation strategy (Reference E39 - U3 Compliance Letter)
(Confirmatory Item# 3.2.1.6.E). Tracked by ONS NTM 01938086-09.
Encl. Page - 9 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8) r.....
. " ' *ISE Confirmatory; Items :* ' ..' . St~tus *
- 14. Confirm that the analysis to determine Oconee's boration Completed requirements in Phase 2 of the mitigating strategy (Reference E37 - U2 & U3 Compliance provides acceptable results (Confirmatory Item# Matrices) 3.2.1.8.A). Closed during NRC July 2015 Audit.
- 15. Confirm that the BWST design provides tornado missile Completed protection to ensure a source of borated water (Reference E37 - U2 & U3 Compliance (Confirmatory Item# 3.2.1.8.C). Matrices)
Closed during NRC July 2015 Audit.
- 16. Confirm the portable pump capability requirements and Completed fuel requirements to implement Phase 2 and Phase 3 (Reference E37 - U2 & U3 Compliance strategies (Confirmatory Item# 3.2.1.9.A). Matrices)
Closed during NRC July 2015 Audit.
- 17. Confirm acceptability of the SFP cooling strategy when it Completed is completed (Confirmatory Item# 3.2.2.A). (Reference E37 - U2 & U3 Compliance Matrices)
Closed during NRC July 2015 Audit.
- 18. Confirm that the results of the licensee's containment Completed analysis beyond 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> are acceptable (ONS open item (Reference E37 - U2 & U3 Compliance
- 26) (Confirmatory Item# 3.2.3.A). Matrices)
Closed during NRC July 2015 Audit.
- 19. Confirm using the analysis of hydrogen buildup (open Completed item 24), that there will be no impact on the Phase 2 (Reference E37 - U2 & U3 Compliance ventilation strategies (Confirmatory Item# 3.2.4.2.A). Matrices)
Closed during NRC July 2015 Audit.
- 20. Confirm that the results of ONS's evaluation of building Completed and area temperatures (licensee-identified open item 32), (Reference E3 7 - U2 & U3 Compliance are acceptable to support the licensee's proposed ELAP Matrices) mitigation strategies (Confirmatory Item# 3.2.4.2.B). Closed during NRC July 2015 Audit.
- 21. Confirm that the licensee's evaluation of freeze protection Completed (ONS open item 37) is acceptable (Reference E37 - U2 & U3 Compliance (Confirmatory Item# 3.2.4.3.A). Matrices)
Closed during NRC July 2015 Audit.
- 22. Confirm that the licensee's analysis of lighting (open item Completed
- 29) is acceptable (Confirmatory Item# 3.2.4.4.A). (Reference E3 7 - U2 & U3 Compliance Matrices)
Closed during NRC July 2015 Audit.
- 23. Confirm that upgrades to the site's communications Completed systems have been completed (Confirmatory Item# (Reference E3 7 - U2 & U3 Compliance 3.2.4.4.B). Matrices)
Closed during NRC July 2015 Audit.
- 24. Confirm that ONS's FLEX strategies with regard to Completed protected and internal locked area access are acceptable (Reference E37 - U2 & U3 Compliance (Confirmatory Item# 3.2.4.5.A). Matrices)
Closed during NRC July 2015 Audit.
- 25. Confirm that the use of non-safety related installed Completed equipment (licensee's open item 3 8) is acceptable (Reference E3 7 - U2 & U3 Compliance (Confirmatory Item# 3.2.4.7.A). Matrices)
Closed during NRC July 2015 Audit.
Encl. Page -10 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
- ,.
ISE Confirmatory Items -Status
- 26. Confirm that the licensee's strategy for providing Completed chemical treatment pond make up water at a rate of (Reference E3 7 - U2 & U3 Compliance 700,000 gallons per day following a flooding event is Matrices) acceptable. This is ONS Open Item 23 in the Integrated Closed during NRC July 2015 Audit.
Plan (Confirmatory Item# 3.2.4.7.B).
- 27. Confirm that ONS's processes and procedures to prevent inappropriate interactions of portable electrical power Completed sources with permanent plant equipment (ONS's open (Reference E37 - U2 & U3 Compliance item 4) conforms to the guidance in NEI 12-06, Section Matrices) 3.2.2, Guideline (13), or provides an acceptable Closed during NRC July 2015 Audit.
alternative to that guidance (Confirmatory Item#
3.2.4.8.A).
- 28. Confirm that the licensee's FLEX generator sizing Completed calculations/analysis and single line diagrams showing (Reference E37 - U2 & U3 Compliance proposed connections of FLEX electrical equipment are Matrices) acceptable (Confirmatory Item# 3.2.4.8.B). Closed during NRC July 2015 Audit.
- 29. Confirm that the licensee's fuel oil consumption analysis Completed (Reference E25, Att. 4)
(licensee's open item 14) is acceptable Closed during NRC July 2015 Audit.
(Confirmatory Item# 3.2.4.9.A).
- 30. Confirm the licensee has considered the coordination of SSF and portable equipment during a "T=O" event, explaining what criteria will be used to determine when Completed (Reference E25, Att. 1) to switch from use of the SSF to use of portable Closed during NRC July 2015 Audit.
equipment and to explain whether the SSF can be used beyond 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> (Confirmatory Item# 3.2.4.9.B).
- 31. Confirm that the licensee's analyses on load shedding (licensee's open item 12), and summaries of battery Completed (Reference E25 Att. 3) sizing calculations for both seismic and flooding Closed during NRC July 2015 Audit.
scenarios of ELAP are acceptable (Confirmatory Item# 3.2.4.10.A).
- 32. Confirm that the licensee's implementation of Completed maintenance and testing guidance for FLEX equipment is (Reference E3 7 - U2 & U3 Compliance acceptable (Confirmatory Item# 3.3.1.A). Matrices)
Closed during NRC July 2015 Audit.
- 33. Offsite Resources - Confirm NEI 12-06 Section 12.2, Completed Guidelines 2 through 10, are addressed with SAFER (Reference E3 7 - U2 & U3 Compliance (Confirmatory Item# 3.4.A). Matrices)
Closed during NRC July 2015 Audit.
d) Generic Concerns The following summarizes ONS's review of six generic issues:
- i. Electric Power Research Institute (EPRI) Report 3002001785, Use of Modular Accident Analysis Program (MAAP) in Support of Post-Fukushima Applications and NRC endorsement (Reference ES & Reference E17).
- The Oconee mitigating strategy is evaluated using RELAP5 and RETRAN for the NSSS response, and FATHOMS and GOTHIC for the containment response.
Encl. Page - 11 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8) ii. Electric Power Research Institute (EPRI) Report 3002000623, Nuclear Maintenance Applications Center: Preventive Maintenance Basis for FLEX Equipment and NRC endorsement (Reference E9 & Reference E10).
- ONS intends to follow EPRI Report 30002000623 in the development of maintenance and testing programs for equipment acquired in response to Mitigation Strategies Order EA-12-049 unless otherwise justified.
iii. Westinghouse report, Westinghouse Response to NRC Generic Request for Additional Information (RAI) on CENTS Code in Support of the Pressurized Water Reactor Owners Group (PWROG) and NRC endorsement (Reference E11 &
Reference E12).
- The Oconee mitigating strategy is evaluated using RELAP5 and RETRAN for the NSSS response, and FATHOMS and GOTHIC for the containment response.
iv. Nuclear Energy Institute (NEI) position paper, Position Paper:
Shutdown/Refueling Modes and NRC endorsement (Reference E13 & Reference E14).
- It is Oconee's intent to abide by the NEI position paper for shutdown and refueling modes.
- v. Nuclear Energy Institute (NEI) white paper, Battery Life Issue and NRC endorsement (Reference E15 & Reference E16).
- The SSF has a design basis mission time of 72 nours. ONS plans to utilize the SSF
- as long as it remains operational. After an ELAP is determined, ONS will utilize the SSF in a dual loop feed to cooldown to 240-250 degrees. ONS will simultaneously .
deploy Phase 2 equipment during this timeframe utilizing the priority established from our thermal-hydraulic analysis. All instrument readings required to support the ELAP cool down are available in the SSF during this Phase 1 time period. This will allow time to deploy the primary repower strategy to repower the vital battery chargers and associated busses. Per standard SBO response, a time critical load shed is performed within 30 minutes of loss of power per the blackout tab of the EOP. In order to prevent complete discharge of the control batteries, all loads off the DC buses will be stripped after declaration of an ELAP (approx. T +2 hours) and before T +4 hours (which is the
- current Station Blackout coping limit). The battery charger's ac input and output breakers will remain closed. The vital inverters will be shut down by opening the inverter input and output breakers. These actions will eliminate all the loads on the batteries while leaving the battery chargers connected which will allow the chargers to automatically restart as designed after power is restored via the Phase 2 FLEX primary repower strategy. The alternate repower strategy does not rely on operation of the station batteries. See Reference E25 Attachment 3 for more information.
vi. Westinghouse position paper, Westinghouse Response to NRC Generic Request for Additional information (RAI) on Boron Mixing in support of the Pressurizer Water Reactor Owners Group (PWROG) and NRC endorsement (References E20 & E21).
- Oconee Nuclear Station addresses this generic issue in the ISE Open Item
- 3.2.1.8.B.
Encl. Page -12 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
- 7) Potential Interim Staff Evaluation Impacts Changes to the NRC Phone Audit Questions, OIP Open Items, and ISE Open/Confirmatory Items were dispositioned during the July 2015 NRC Onsite Audit. No other changes have the potential to impact the ISE.
- 8) References The following references support the updates to the Overall Integrated Plan described in this enclosure:
E1. NRC Order Number EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, dated March 12, 2012 (Accession No. ML12054A735).
E2. NRC Interim Staff Guidance JLD-ISG-2012-01, Compliance with Order EA-2-049, Order Modifying Licenses with Regard to Requirements for Mitigation strategies for Beyond-Design-Basis External Events, dated August 29, 2012 (Accession No. ML12229A174).
E3. NEI 12-06, Revision 0, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide, dated August 2012 (Accession No. ML12242A378).
E4. Duke Energy Letter, Oconee Nuclear Station, Units 1 ,2 and 3 Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 28th, 2013 (Accession No. ML13063A065).
ES. Duke Energy Letter, First Six-Month Status Report in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 29, 2013 (Accession No, ML13246A009).
E6. Flow Diagram - Unit 1 & 2 Spent Fuel Cooling System (104A-1.1, Revision 53).
E7. Flow Diagram - Unit 3 Spent Fuel Cooling System (104A-3.1, Revision 48).
ES. EPRI Report 3002001785, Use of Modular Accident Analysts Program (MAAP) in Support of Post-Fukushima Applications, dated June 2013 (Accession No. ML13190A201 ).
E9. EPRI Report 3002000623, Nuclear Maintenance Applications Center: Preventive Maintenance Basis for FLEX Equipment, dated September 2013 (Accession No. ML13276A573).
E10. NRC letter from Jack R. Davis, Director Mitigating Strategies Directorate (NRR), to Nuclear Energy Institute, Mr. Joseph E. Pollock Vice President Nuclear Operations, dated October 7, 2013 (Accession No. ML13276A224).
E11. Westinghouse Report, Westinghouse Response to NRG Generic Request for Additional Information (RA/) on CENTS Code in Support of the Pressurized Water reactor Owners Group (PWROG); dated September 25, 2013{Withheld from public disclosure).
E12. NRC letter from Jack R. Davis, Director Mitigating Strategies Directorate (NRR), to Jack Stringfellow, PWR Owners Group, Program Management - Westinghouse, dated October 7, 2013 (Accession No. ML13276A555).
E13. NEI Position Paper, Shutdown/Refueling Modes, dated September 18, 2013 (Accession No. ML13273A514).
Encl. Page -13 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
E14. NRG letter from Jack R. Davis, Director Mitigating Strategies Directorate (NRR), to Nuclear Energy Institute, Mr. Joseph E. Pollock, Vice President Nuclear Operations, dated September 30, 2013 (Accession No. ML13267A382).
E15. NEI White Paper, Battery Life Issues, dated August 21, 2013 (Accession No. ML13241A186).
E16. NRG letter from Jack R. Davis, Director Mitigating Strategies Directorate (NRR), to Nuclear Energy Institute, Mr. Joseph E. Pollock, Vice President Nuclear Operations, dated September 16, 2013 (Accession No. ML13241A188).
E17. NRG letter from Jack R. Davis, Director Mitigating Strategies Directorate (NRR), to Nuclear Energy Institute, Mr. Joseph E. Pollock, Vice President Nuclear Operations, dated October 3, 2013 (Accession No. ML13275A318).
E18. Duke Energy Letter, Second Six-Month Status Report in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 28, 2014 .(Accession No. ML14064A197).
E19. NRG letter from Jeremy S. Bowen, Mitigating Strategies Directorate (NRR), Mr. Scott Batson, Site Vice President Oconee Nuclear Station, dated February 10, 2014 (Accession No. ML13365A258).
E20. Westinghouse Position Paper, Westinghouse Response to NRG Generic Request for Additional Information (RA/) on Boron Mixing in support of the Pressurizer Water Reactor Owners Group (PWROG), dated August 16, 2013 (Accession No. ML13235A135).
E21 .. NRG letter from Jack R. Davis, Director Mitigating Strategies Directorate (NRR), to Jack Stringfellow, PWR Owners Group, Program Management - Westinghouse, dated January 8, 2014 (Accession No. ML13276A183).
E22. ONS Hydraulic Analysis Calculation - 11232.
E23. ONS Engineering Change Document - 113065.
E24. NEI 12-01, Guideline for Assessing Beyond Design Basis Accident Response Staffing and Communications Capabilities, Revision 0, May 2012 (Accession No. ML12125A412).
E25. ONS Select Fukushima Related Technical Evaluations, Analyses, and Position Papers Calculation ,..11383.
E26. ONS FLEX Strategy Intermediate Cooling Hydraulic Calculation -11329.
E27. ONS Auxiliary Building GOTHIC Heat-Up Analysis - ELAP Event Cases - 11253.
E28. Duke Energy Letter, Third Six-Month Status Report in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 27, 2014 (Accession No. ML14245A018).
E29. Duke Energy Letter, Fourth Six-Month Status Report in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 27, 2015 (Accession No. ML15063A027).
E30. Duke Energy Letter, Fifth Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 26, 2015 (Accession No. ML15247A068).
Encl. Page -14 of 15
ENCLOSURE: ONS SEVENTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)
(Note: The references for this Enclosure are listed in Section 8)
E31. Duke Energy Letter, Notification of Compliance with Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond Design Basis External Events for Oconee Nuclear Station, Unit 2 (Accession No. ML16028A194).
E32. ONS Station Calculation - 10865 Revision 1.
E33. NRC letter from Juan F. Uribe, Hazards Management Branch Japan Lessons-Learned Division Project Manager, to Mr. Scott Batson, Site Vice President Oconee Nuclear Station, dated September 24, 2015 (Accession No. ML15239B261 ).
E34. CSD-EG-ONS-1619.1000 Diverse and Flexible Coping Strategies (FLEX) Program Document - Oconee Nuclear Station, Revision 0.
- E35. CSD-EG-ONS-1619.1001 SAFER Response Plan for Oconee Nuclear Station, Revision 1.
E36. ONS Engineering Change Document - 112453.
E37. CSD-EG-ONS-1619.1003 Compliance Matrices for NRG Orders EA-12-049 and EA-12-051 (Place Holder).
E38. Oconee Nuclear Station's Sixth Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) dated February 29, 2016 (Accession No. ML16064A091)..
E39. Duke Energy Letter, Notification of Compliance with Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond Design Basis External Events for Oconee Nuclear Station, Unit 3 (Accession No. M.L 16200A315).
Encl. Page - 15 of 15