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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)
	ML16064A091
Person / Time
Site:	Oconee
Issue date:	02/29/2016
From:	Batson S; Duke Energy Carolinas
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	EA-12-049, ONS-2016-024
	Download: ML16064A091 (17)
	v • d • e

Vice President ENERGYDU EScotL. Laso Oconee Nuclear Station Duke Energy ONOIVP 7800 Rochester Hwy ONS-201 6-024 Seneca, SC 29672 0; 864.873.3274

f. 864.873. 4208 Scott.Batson@duke-energy.com February 29, 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:

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)

References:

1. Nuclear Regulatory Commission (NRC) Order Number EA-1 2-049, 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 Mitigation Strategies for Beyond-Design-Basis External Events (OrderEA-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-basisExternal 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 Strategiesfor 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 OrderModifying 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. ML14245A019).

6. Oconee Nuclear Station's Fourth Six-Month Status Report in Response to March 12, 2012 Commission OrderModifying 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. ML15247A069).

8. NEI 12-06, [Rev. 0], Diverse and Flexible Coping Strategies (FLEX) Implementation Guide, dated August 2012 (Accession No. ML12242A378). _.

ONS-201 6-024 February 29, 2016 Page 2 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 five six-month reports (References 3 to 7) for Oconee Nuclear Station. The purpose of this letter is to provide the sixth 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 8) during the July 29, 2015 to January 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 February 29, 2016.

Sincerely, Scott L. Batson Vice President Oconee Nuclear Station

Enclosure:

1. Oconee Nuclear Station, Sixth Six-Month Status Report for Order EA-12-049 (FLEX),

Units 1, 2, and 3.

ONS-201 6-024 February 29, 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, MIS O-8G9A Rockville, MD 20852-2746 Mr. Jeffery Whited (by electronic mail only)

U.S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop O-8B1A Rockville, MD 20852 Mr. Eddy Crowe NRC Senior Resident Inspector Oconee Nuclear Station

ENCLOSURE 1 Oconee Nuclear Station (ONS)

Sixth Six Month Status Report for Order EA-12-049 (FLEX),

Units 1, 2, and 3 Encl. Page 1 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note:~The referencesfor this Enclosure are listed in Section 8)

1) Introduction On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued Order EA-12-049 (Reference El) 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. Five six-month updates have subsequently been submitted to the NRC (References E5, E18, E28, E29 and E30).

This report constitutes the sixth 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 July 29, 2015 to January 28, 2016 (hereafter referred to as "1the update period).

2) Milestone Accomplishments (during the update period)

The following milestone(s) were completed:

1. The fifth six-month status report was submitted August 26, 2015.

2. Unit 2 Implementation and Implementation Walkdowns were completed.

3. Unit 2 Training was implemented.

4. Unit 2 is considered in compliance with NRC Order EA-12-049 as of November 11lth, 2015 (Reference E31 ).

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.

Target Completion Revised Target Milestone Date Activity Status Completion Date Licensing Actions:

Submit Overall Integrated Plan Feb 2013 Complete Date Not Revised Submit 6 Month Update 1 Aug 2013 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 Aug 2015 Complete Date Not Revised Submit 6 Month Update 6 Feb 2016 This Submittal Date Not Revised Submit 6 Month Update 7 Aug 2016 Not Started Date Not Revised Encl. Page - 2 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note." The referencesfor this Enclosure are listed in Section 8)

Target Completion Revised Target_

Milestone Date Activity Status [Completion Date Modifications:

Develop Modifications ]Aug 2016 Started [Date Not Revised Procurement: ' " "

Identify Significant Material/Equipment Sept 2013 Complete Date Not Revised Material/Equipment August SatdUnits 1 and 3 Schedule Procurement/Delivery 2016 tedDate Revised Implementation Walkdowns:

Conduct N-i Outage Walkdowns - Ul Nov 2014 Complete Date Not Revised Conduct N-i Outage Walkdowns - U2 Nov 2013 Complete Date Not Revised Conduct N-i Outage Walkdowns - U3 May 2014 Complete Date Not Revised Conduct Implementation Walkdowns - Ul Oct 2016 Not Started Date Not Revised Conduct Implementation Walkdowns - U2 Oct 2015 Complete Date Not Revised IConduct Implementation Walkdowns - U3 April 2016 Started Date Not Revised Staffing:________________

Conduct Staffing Analysis ]July 2016 [ Complete [Date Not Revised iTraining:

Develop Training program - Ul July 2016 Started Date Not Revised Develop Training program - U2 July 2015 Complete Date Not Revised Develop Training program - U3 April 2016 Started Date Revised Implement Training - U1 Oct 2016 Started Date Not Revised Implement Training - U2 Oct 2015 Complete Date Not Revised Implement Training - U3 April 2016 Started Date Not Revised Pr~ocedures: ...

Develop FLEX Guidelines (FGs) June 2016 Started Date Not Revised Develop Maintenance Procedures June 2016 Started Date Not Revised*

Regional Response Centers:

{

Develop Strategies/Playbook with RRC April 2015 Complete Date Not Revised Install Offsite Delivery Pad March 2015 Complete Aust21

____________________________ _________(Installation not required) Aust01 Implementation:-___________________________

Implement Modifications - U1 Nov 2016 Started Date Not Revised Implement Modifications - U2 Nov 2015 Complete Date Not Revised Implement Modifications - U3 May 2016 Started Date Not Revised Endl. Page - 3 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note: The referencesfor 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.

Providedon the Fifth Six-Month Status Report (Reference E30):

During the July 2015 NRC 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 NRC Auditors'perspective was that creditingADV operation should be considered an alternate approach to NEI 12-06. Oconee acknowledges this position. Justification is provided in 0SC-11383 0 (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 Integrated Plan Open Items Status Completed (References E32 and E33)

1. Revised PMP HIMR51 Analysis Analysis approved by the NRC.

Tracked by ONS NTM 01935875-01.

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 (Reference E37 - U2 Compliance Matrix)

3. Deployment Path Program Tracked by ONS NTM 01935875-03.

On track for Unit 1 and 3 implementation.

Closed during NRC July 2015 Audit.

Completed for Unit 2 (Reference E37 - U2 Compliance Matrix)

4. Procedures and FSGs Tracked by ONS NTM 0 1935875-04.

On track for Unit 1 and 3 implementation.

Closed during NRC July 2015 Audit.

Completed for Unit 2

5. FLEX Equipment Programmatic Control Takdb N T 957-5 On track for Unit 1 and 3 implementation.

Closed during NRC July 2015 Audit.

Encd. Page -4 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(No te:~The referencesfor this Enclosure are listed in Section 8)

Overall Integrated Plan Open Items Status Completed for Unit 2 (Reference E37 - U2 Compliance Matrix)

6. Personnel Training Tracked by ONS NTM 01935875-06.

On track for Unit 1 and 3 implementation.

Closed during NRC July 2015 Audit.

Completed for Unit 2 (Reference E34)

(Reference E37 - U2 Compliance Matrix)

7. FLEX Basis Document Tracked by ONS NTM 01935875-07.

On track for Unit 1 and 3 implementation.

Closed during NRC July 2015 Audit.

Completed for Unit 2 (Reference E37 - U2 Compliance Matrix)

8. Configuration Control Tracked by ONS NTM 01935 875-08.

On track for Unit 1 and 3 implementation.

Closed during NRC July 2015 Audit.

Completed (Reference E3 5)

9. RRC Tracked by ONS NTM 01935875-09.

Closed during NRC July 2015 Audit.

Initial analyses complete. Additional cases are

10. Cooldown Analysis being incorporated.

Tracked by ONS NTM 0 1935875-10.

Closed during NRC July 2015 Audit.

Completed

11. ADV Survivability and Accessibility (Reference E3 7 - U2 Compliance Matrix)

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 0 1935875-15.

________________________________Closed during NRC July 2015 Audit.

16. Water in embedded CCW lines & Hydraulic Completed (Reference Tracked by ONS NTM E26) 0 1935875-16.

Analysis for Pumping Configuration Closed during NRC July 2015 Audit.

Completed

17. PSW Modification (BC 91877) Tracked by ONS NTM 01935875-17.

Closed during NRC July 2015 Audit.

18. Alternate FLEX Connections Modification Completed (Reference E23)

(SG Makeup) Tracked by ONS NTM 01935875-18.

______________________________Closed during NRC July 2015 Audit.

Encl. Page - 5of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note. The referencesfor this Enclosure are listed in Section 8)

Overall Integrated Plan Open Items Status Completed for Unit 2 Tracked by ONS NTM 01935875-19.

19. Breaking Siphons in Embedded CCW Piping On track for Unit 1 and 3 implementation.

Closed during NRC July 2015 Audit.

Completed for Unit 2

20. nstrmenatio Repwer(Reference E37 - U2 Compliance Matrix)

(AInterumntate o RepowerStaey Tracked by ONS NTM 01935875-20.

(Altrnat tratgy)OnRepwer track for Unit 1 and 3 implementation.

Closed during NRC July 2015 Audit.

Completed (Reference E3 6)

21. FLEX Equipment Storage Tracked by ONS NTM 01935875-21.

Closed during NRC July 2015 Audit.

Completed for Unit 2

22. Portable Power Distribution (Reference E37 - U2 Compliance Matrix)

(Primary Repower Strategy) Tracked by ONS NTM 0 1935875-22.

On track for Unit 1 and 3. implementation.

________________________________Closed during NRC July 2015 Audit.

Completed

23. ong ad ermSG SP Maeup(Reference E37 - U2 Compliance Matrix)

23. ong ad SP ermSG MaeupTracked by ONS NTM 01935875-23.

Closed during NRC July 2015 Audit.

Completed

24. ydrgenBuilup nalsis(Reference E27: Sect. 3.14 and Att. E) 24.

Bildu ydroen AnaysisTracked by ONS NTM 0 1935875-24.

Closed during NRC July 2015 Audit.

Completed for Unit 2

25. BWST Tap Analysis and Modification (RCS (Reference E37 - U2 Compliance Matrix)

Makeup) Tracked by ONS NTM 01935875-25.

On track for Unit 1 and 3 implementation.

Closed during NRC July 2015 Audit.

Completed (Reference E37 - U2 Compliance Matrix)

26. Containment Analysis Tracked by ONS NTM 0 1935875-26.

Closed during NRC July 2015 Audit.

Completed

27. Hydraulic Analysis for Pump Flow (CTP-1 to (Reference E37 - U2 Compliance Matrix)

SFPs & Intake 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 0 1935875-28.

Closed during NRC July 2015 Audit.

Completed

29. ightng Ealuaion(Reference E3 7 - U2 Compliance Matrix) 29.

EaluaionTracked ightng by ONS NTM 01935875-29.

Closed during NRC July 2015 Audit.

Completed

30. ommuicaton Asessent(Reference E37 - U2 Compliance Matrix)

30. ommuicaton AsessentTracked by ONS NTM 01935875-30.

Closed during NRC July 2015 Audit.

Endl. Page - 6 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note: The referencesfor this Enclosure are listed in Section 8)

Overall Integrated Plan Open Items Status Completed

31. NEI 12-01 Staffing Study (Reference E37 - U2 Compliance Matrix)

(Reference E24) Tracked by ONS NTM 01935875-31.

Closed during NRC July 2015 Audit.

Completed (Reference E37 - U2 Compliance Matrix)

32. HVAC Analysis Tracked by ONS NTM 01935875-32.

Closed during NRC July 2015 Audit.

b) Open Items added after February 2 8 th, 2013 Open Items Status

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 strategy to enhance deployment times by utilizing Completed for Unit 2 a small 120 VAC portable diesel generator (Reference E37 - U2 Compliance Matrix)

(approximately 6000 watts) deployed on the Tracked by ONS NTM 01935875-34.

Turbine Building deck to provide 120 VAC feeds On track for Unit 1 and 3 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 OWIjAssumption #8] is still Ti tmspree yOe tm4 conservative with respect to the Defense in Depth Trackiedmb Nsupree NTM 01935875-35.

Modifications analyzed in OTP Reference 48 (which used a slightly modified model run) and Closed during NRC July 2015 Audit.

the credited CAL model run in OIP reference 14.

36. Perform raw water fouling analysis for core Completed cooling and heat removal. (Reference E37 - U2 Compliance Matrix)

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 Compliance Matrix) strategies. 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 E3 7 - U2 Compliance Matrix) for mitigating an ELAP event. Tracked by ONS NTM 01935875-38.

Closed during NRC July 2015 Audit.

39. FLEX Strategy for Shutdown Modes: Determine Completed for Unit 2 what mods, procedures, equipment, etc. is needed (Reference E37 - U2 Compliance Matrix) to support a Shutdown Modes FLEX Strategy. Tracked by ONS NTM 0 1935875-39.

On track for Units 1 and 3 implementation.

Closed during NRC July 2015 Audit.

40. Clarification of Applicable External Flooding Completed Hazard at ONS. (Reference E37 - U2 Compliance Matrix)

Tracked by ONS NTM 01935 875-40.

Closed during NRC July 2015 Audit.

Endl. Page - 7 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note: The referencesfor this Enclosure are listed in Section 8) c) Interim Staff Evaluation (ISE)

ISE Open Items Status

1. Provide a description and justification for the specific Open evaluation model(s) used in the ELAP analyses for (Reference E3 1 - U2 Compliance Letter)

Oconee (ISE Open Item # 3.2.1.l .A). 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 S SF 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 E37 - U2 Compliance Matrix)

(ISE Open Item # 3.2.1 .6.B). Closed during NRC July 2015 Audit.

4. When further analyses are completed, the licensee should provide additional information that either supports a Open conclusion that pressurizer relief or safety valves do not (Reference E3 1 - U2 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).

5. Provide additional information demonstrating successful mitigation of an ELAP event involving an uncontrolled Open cooldown resulting from consequential damage to the (Reference E3 1 - U2 Compliance Letter) main steam system due to the severe natural hazard that Tracked by ONS NTM 0193 8086-04.

initiates the ELAP event (ISE Open Item # 3.2.1.6.D).

6. Demonstrate that Oconee's approach for modeling boric acid mixing is consistent with a generically acceptable Coped methodology or develop a plant-specific technical basis toCoped suportthemoelig asuptins orborc aidmixing in (Reference E37 - U2 Compliance Matrix) spotthe modeanlyinassumpticonseoeorcai Closed during NRC July 2015 Audit.

(ISE Open Item # 3.2.1.8.B).

ISE Confirmatory Items Status

1. Confirm that ONS's final FLEX equipment deployment routes include adequate consideration of potential soil Completed liquefaction or other conditions that could impede (Reference E37 - U2 Compliance Matrix) 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 guidance for operators to obtain instrument readings Completed under ELAP conditions adequately addresses the (Reference E37 - U2 Compliance Matrix) considerations in NEI 12-06, Section 5.3.3, consideration Closed during NRC July 2015 Audit.

(1) (Confirmatory Item # 3.1.1.3.A).

3. Confrmn that the details for delivery and staging of off-site resources in the licensee's RRC playbook developed Completed by the SAFER team and the utility are acceptable for all (Reference E37 - U2 Compliance Matrix)

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, Coped consideration 2, confirm that persistent, prohibitive (Rmpeferecd3 2Cmlac arx flooding levels will not occur at the ONS site Cloedfdringe NRCU Jul2015oAudianeMt.ix (Confirmatory Item #_3.1 .2.2.A). ClosedduringNRCJuly_2015_Audit.

Encl. Page - 8 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note: The referencesfor this Enclosure are listed in Section 8)

S ISE Confirmatory Items , Status

5. Confirm that the final ELAP computer code analyses for core cooling, reactor coolant system inventory, shutdown Open margin, and containment integrity have acceptable (Reference E3 1 - U2 Compliance Letter) methodology and assumptions and support the sequence Tracked by ONS NTM 01938086-05.

of events timeline (Confirmatory Item # 3.2.l.1 .B).

6. Reliance on the RELAP5iMOD2- Babcock & Wilcox (B&W) and RETRAN-30 codes in the ELAP analysis forCoped B&W plants should be limited at the present time to the (Rmpeferecd3 2Cmlac arx flow conditions prior to boiler-condenser cooling (eeec 3 2Cmlac arx initiation. Confirm that the code is not used outside this Closed during NRC July 2015 Audit.

range (Confrm-atory Item # 3.2.1.1 .C).

7. Confirm the means of isolatingRCP seal return and RCS Completed letdown in accordance with the Jocassee dam break (eeec 3 2Cmlac arx procedure and the associated timeframe Cloeddringe N3 U C Jul2015oAudianeMt.ix (Confirmatory Item #i 3.2.1.2.A). Coe uigNCJl 05Adt

8. Confirm that RCP seal temperature would be maintained at an acceptably low value by establishing injection flow Open to the RCP seals via the SSF RCMU pump within 20 (Reference E3 1 - U2 Compliance Letter) minutes of event initiation (Confirmatory Item # Tracked by ONS NTM 01938086-06.

3.2.l.2.B).

9. Confirm there is justification for the assumed seal Open leakage rates for the Bingham RCPs with Sulzer seal (Reference E3 1 - U2 Compliance Letter) assemblies (Confirmatory Item # 3.2.1.2.C). Tracked by ONS NTM 0 1938086-07.

10. Confirm there is justification for the assumed seal leakage rates for the Westinghouse 93-A RCPs with Open Flowerv N-000seas wth he beyncefeaure (Reference E3 1 - U2 Compliance Letter)

(Confirmatory Item # 3.2.l.2.D).TrcebyOSNM0986-.

11. Confirm that steam generator pressure indication will be available to support the cooldown directed by the ELAP mitigating strategy, or provide adequate basis that such Completed indication is unnecessary even at average reactor coolant Cloedfdringe NRCU2015oAudianeMt.ix Jul temperatures below 525 degrees Fahrenheit Coe uigNCJl 05Adt (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 Compliance Matrix) credited instrumentation (Confirmatory Item # 3.2.1 .5.B). Closed during NRC July 2015 Audit.

13. When evaluations are completed, confirm that the Oe survivability and performance of the atmospheric dump (RfeenceE 2Cmlac etr valves is adequate to support ONS's mitigation strategy TRfrancked by ON1 NTM 01938086-09.ter (Confirmatory Item # 3.2.1.6.E).TrcebyOSNM0986-.

14. Confirm that the analysis to determine Oconee's boration Completed requirements in Phase 2 of the mitigating strategy (Reference E37 - U2 Compliance Matrix) provides acceptable results (Confirmatory Item # Coe uigNCJl 05Adt 3.2.1.8.A). Coe uigNCJl 05Adt

15. Confirm that the BWST design provides tornado missile Completed protection to ensure a source of borated water (Reference E37 - U2 Compliance Matrix)

(Confirmatory Item # 3.2.1 .8.C). 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 Compliance Matrix) strategies (Confirmatory Item # 3.2.1 .9.A). Closed during NRC July 2015 Audit.

Endl. Page - 9 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note: The referencesfor this Enclosure are listed in Section 8)

ISE Confirmatory Items Status

17. Confirm acceptability of the SFP cooling strategy when it Completed is completed (Confirmatory Item ft 3.2.2.A). (Reference E37 - U2 Compliance Matrix)

______________________________________Closed during NRC July 2015 Audit.

18. Confirm that the results of the licensee's containment Completed analysis beyond 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months are acceptable (ONS open item (Reference E37 - U2 Compliance Matrix)

26) (Confirmatory Item ft 3.2.3.A). 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 Compliance Matrix) ventilation strategies (Confirmatory Item #t 3.2.4.2.A). Closed during NRC July 2015 Audit.

20. Confimt that the results of ONS's evaluation of building and area temperatures (licensee-identified open item 32), Completed are acceptable to support the licensee's proposed ELAP (Reference E37 - U2 Compliance Matrix) 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 Compliance Matrix)

(Confirmatory Item ft 3.2.4.3.A). Closed during NRC July 2015 Audit.

22. Confirm that the licensee's analysis of lighting (open item Completed

29) is acceptable (Confirmatory Item ft 3.2.4.4.A). (Reference E37 - U2 Compliance Matrix)

Closed during NRC July 2015 Audit.

23. Confirm that upgrades to the site's communications Completed systems have been completed (Confirmatory Item ft (Reference E37 - U2 Compliance Matrix) 3.2.4.4.B). 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 Compliance Matrix)

(Confirmatory Item ft 3.2.4.5.A). Closed during NRC July 2015 Audit.

25. Confirm that the use of non-safety related installed Completed equipment (licensee's open item 38) is acceptable (Reference E37 - U2 Compliance Matrix)

(Confirmatory Item ft 3.2.4.7.A). Closed during NRC July 2015 Audit.

26. Confirm that the licensee's strategy for providing chemical treatment pond make up water at a rate of Completed 700,000 gallons per day following a flooding event is (Reference E37 - U2 Compliance Matrix) acceptable. This is ONS Open Item 23 in the Integrated Closed during NRC July 2015 Audit.

Plan (Confirmatory Item ft 3.2.4.7.B). ________________

27. Confirm that ONS's processes and procedures to prevent inappropriate interactions of portable electrical power sources with permanent plant equipment (ONS's open Completed item 4) conforms to the guidance in NEI 12-06, Section (Reference E37 - U2 Compliance Matrix) 3.2.2, Guideline (13), or provides an acceptable Closed during NRC July 2015 Audit.

alternative to that guidance (Confirmatory Item ft 3.2.4.8.A). _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

28. Confirm that the licensee's FLEX generator sizingCoped calculations/analysis and single line diagrams showing Competedec 3 2Cmlac arx prpsdconnections of FLEX electrical equipment are (eeec 3 2Cmlac arx acceptable (Confirmatory Item #t 3.2.4.8.B). Coe uigNCJl 05Adt

29. Confirm that the licensee's fuel oil consumption analysis Completed (Reference E25, Att. 4)

(licensee's open item 14) is acceptable Coe uigNCJl 05Adt (Confirmatory Item ft_3.2.4.9.A). Closed during NRC July 2015 Audit. _

Endl. Page - 10 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note: The references for this Enclosure are listed in Section 8)

30. Confirm the licensee has considered the coordination of SSF and portable equipment during a "T=0 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 0.02 hours 1.190476e-4 weeks 2.7396e-5 months (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 Cmltd(eeec 2 t.3 sizing calculations for both seismic and flooding Clospeedduin(RCfeJuly 205 Audt.3 scenarios of ELAIP are acceptable Coe uigNCJl 05Adt (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 E37 - U2 Compliance Matrix) acceptable (Confirmatory Item # 3.3.1 .A). 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 E37 - U2 Compliance Matrix)

(Confirmatory Item # 3.4.A). 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 E8 & Reference E17).

The Oconee mitigating strategy is evaluated using RELAP5 and RETRAN for the NSSS response, and FATHOMS and GOTHIC for the containment response.

ii. Electric Power Research Institute (EPRI) Report 3002000623, Nuclear Maintenance Applications Center: Preventive Maintenance Basis for FLEX Equipment and NRC endorsement (Reference E9 & Reference EI0),

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-1 2-049 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 Eli &

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 El14).

It is Oconee's intent to abide by the NEI position paper for shutdown and refueling modes.

Endl. Page- 11 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note. The references for this Enclosure are listed in Section 8)

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 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . 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 without performing additional load shedding. This approach eliminates resources required to perform additional load shedding activities on all 3 units in the T+2, to T+3 hour timeframe in which many critical activities are underway and eliminates potential unanticipated interactions created by load shed activities.

Based on the above, the station vital batteries will be available for approximately 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months after loss of power.

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 will address this generic issue in the ISE Open Item

3.2.1 .8.B.

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:

El. 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-201 2-01, Compliance with Order EA-2-049, Order Modifying Licenses with Regard to Requirements for Mitigation strategiesfor Beyond-Design-BasisExternal 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 IntegratedPlan in Response to March 12, 2012 Commission OrderModifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 2 8 th, 2013 (Accession No. ML13063A065).

E5. Duke Energy Letter, FirstSix-Month Status Report in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Encl. Page-l12 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note: The referencesfor this Enclosure are listed in Section 8)

Strategies for Beyond-Design-Basis External Events (OrderNumber 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).

E8. EPRI Report 3002001785, Use of Modular Accident Analysis Program (MAAP) in Support of Post-FukushimaApplications, dated June 2013 (Accession No. ML13190A201 ).

E9. EPRI Report 3002000623, Nuclear MaintenanceApplcations Center: Preventive Maintenance Basis for FLEX Equipment, dated September 2013 (Accession No. ML13276A573).

EI0. 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).

Eli1. Westinghouse Report, Westinghouse Response to NRC Generic Request for Additional Information (RAI) on CENTS Code in Support of the PressurizedWater 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).

E14. NRC 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. NRC 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. 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 3, 2013 (Accession No. ML13275A318).

El18. Duke Energy Letter, Second Six-Month Status Report in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategiesfor Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 28, 2014 (Accession No. ML14064A197).

E19. NRC 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 NRC Generic Request for Additional In formation (RAI) on Boron Mixing in support of the Pressurizer Water Reactor Owners Group (PWROG), dated August 16, 2013 (Accession No. ML13235A135).

E21. NRC 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.

Encl. Page -13 of 14

ENCLOSURE: ONS SIXTH SIX-MONTH STATUS REPORT (ORDER EA-12-049) (FLEX)

(Note: The referencesfor this Enclosure are listed in Section 8)

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 OrderModifying 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. ML14245A019).

E29. Duke Energy Letter, Fourth Six-Month Status Report in Response to March 12, 2012, Commission OrderModifying 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 OrderModifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (OrderNumber EA-12-049), dated August 26, 2015 (Accession No. ML15247A069).

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-1 619.1000 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 NRC Orders EA-12-049 and EA- 12-051 ( Place Holder).

Encl. Page-l14 of 14