NG-16-0169, Duane Arnold, 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

Duane Arnold, 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

ML16246A009
Person / Time
Site:	Duane Arnold
Issue date:	08/31/2016
From:	Vehec T NextEra Energy Duane Arnold
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-12-049, NG-16-0169
Download: ML16246A009 (11)

Text

August 31, 2016 NG-16-0169 10 CFR 2.202 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Duane Arnold Energy Center Docket No. 50-331 -

Renewed Op. License No. DPR-49 NextEra Energy Duane Arnold Energy Center. LLC's 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) Order EA-12-049. "Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events." dated March 12. 2012(ML12056A045)

2) Letter. R. Anderson (NextEra Energy Duane Arnold, LLC) to U. S. NRC. "NextEra Energy Duane Arnold. LLC's 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)," NG-13-0084, dated February 28.

2013(ML13063A148)

On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued Reference 1, an immediately effective Order to all licensees including NextEra Energy Duane Arnold, LLC (hereafter NextEra Energy Duane Arnoldr In Reference 2, NextEra Energy Duane Arnold submitted an Overall Integrated Plan for the implementation of this Order. The Order required Licensee's to provide periodic status reports for the Overall Integrated Plan.

NextEra Energy Duane Arnold, LLC, 3277 DAEC Road, Palo, IA 52324

Document Control Desk NG-16-0169 Page 2of2 The purpose of this letter is to provide the next six-month status report pursuant to Section IV, Condition C.2, of Reference 1, that delineates progress made in implementing the requirements of Reference 1. The enclosure to this letter provides an update of milestone accomplishments since the last status report,

• including any changes to the compliance method, schedule, or need for relief and the basis, if any.

If you have any questions or require additional information, contact Mike Matchinis at 319.,851-7756.

• I declare under penalty of perjury that the foregoing is true and correct.

Execute on August 31., 2016.

T. A. V~h_ec Vice President, Duane Arnold Energy Center NextEra Energy Duane Arnold, LLC Enclosure cc: Regional Administrator, USNRC, Region Ill Resident Inspector, USNRC, Duane Arnold Energy Center Project Manager, USNRC, Duane Arnold Energy Center

Attachment to NG-16-0169 NextEra Energy Duane Arnold, LLC's Six Month Status Report for the Implementation of Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events 8 pages follow

NextEra Energy Duane Arnold, LLC's Six Month Status Report for the Implementation of Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events

1. Introduction NextEra Energy Duane Arnold, LLC (hereafter, NextEra Energy Duane Arnold)

• developed an Overall Integrated Plan (Reference 2), documenting the diverse and flexible strategies (FLEX), in response to Reference 1. This attachment provides an update of milestone accomplishments since submittal of the Overall Integrated Plan, including any changes to the compliance method, schedule, or need for relief/relaxation and the basis, if any.

2. Milestone Accomplishments

.The following milestone(s) have been completed since the submittal of the last six

• month update (Reference 9), and are current as of August 19, 2016.

• Complete Staffing Study for Flex Implementation

• Validate that time sensitive actions can be completed consistent with the Flex Strategies

• Submit 6 month status report

3. Milestone Schedule Status The following provides an update to Attachment 4 of the Overall Integrated Plan (Reference 2) as modified by Reference 3. It provides the activity status of each item, and whether the expected completion date has changed. The dates are planning dates . * * --

subject to change as design and implementation details are developed.

The revised milestone target completion dates do not impact the order implementation date.

Revised Target Activity Target Milestone Completion Status Completion Date Date Submit Overall Integrated Implementation Plan February 2013 Completed N/A Submit 6 Month Status Report Auaust 2013 Comoleted N/A Complete Revision to Emergency Operating Procedures to Extend Completed Operation of Steam Driven Pumps December 2013 Januarv 2014 N/A Submit 6 Month Status Report February 2014 Completed N/A Complete Regional Response Center Arrangements December 2015 Comoleted* N/A Submit 6 Month Status Report August2014 Completed N/A First Refueling Outage of RF024 Implementation Period (Fall 2014) Completed N/A Page 1 of 8

Revised Target Activity Target Milestone Completion Status Completion Date Date Complete Site Specific Analysis of NEDC-33771 P Rev. 1 January 2015 Completed N/A Submit 6 Month Status Report Februarv 2015 Completed N/A FLEX Storage Buildings Completed March 2015 Completed N/A September 2016 Procurement o1 primary portable Identified Portable Equipment Stored on equipment is Site May 2016 Started complete.

Submit 6 Month Status Report August 2015 Completed N/A Issue Modification Packaqes December 2015 Completed N/A Submit 6 Month Status Report February 2016 Completed N/A Complete Staffing Study for Flex Implementation May 2016 Completed N/A Validate that time sensitive actions can be completed consistent with the Flex Strategies August 2016 Completed N/A Complete Implementing Procedure Started September Development and Validation Auqust 2016 2016 Completed N/A with this Submit 6 Month Status Report August 2016 submittal Complete Required Training September 2016 Started N/A Final Implementation Outage for RFO 25 Modifications (Fall 2016) Not Started N/A Submit Completion Report December 2016 Not Started N/A

4. Changes to Compliance Method Changes in compliance methods have been described in previous six month status updates (References 7 and 8). A revision to one of the changes discussed in Reference 7 was identified during this period:

Reference 7 indicated that rather than installing a transfer panel for connection of a 4160 volt generator in Phase 3, a portable device would be used that could be inserted into an existing breaker to allow ready connection of the portable generator to station 4160 Volt distribution. As identified in Section 6 below, rather than using a portable device, procedures will direct the connection of the 4160 VAC generator to the Standby Transformer secondary or the essential bus feeder lines. This will supply power to one or both essential 4160 VAC buses. This does not change the function of providing a connection for portable 4160 volt generation in Phase 3.

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5. Need for Relief/Relaxation and Basis for the Relief/Relaxation NextEra Energy Duane Arnold expects to comply with the order implementation date and no relief/relaxation is required at this time.

6. Open Items from Overall Integrated Plan and Interim Staff Evaluation The following tables provide a summary of the open items documented in the Overall Integrated Plan or the Interim Staff Evaluation (SE) and the status of each item.

Overall Integrated Plan Pending Actions Status 1 Seismic re-evaluations pursuant to the 10 CFR Completed. Reference 5 submitted 50.54(f) letter of March 12, 2012 are not completed the seismic re-evaluation to the NRC.

and therefore not assumed in this submittal. As the No issues impacting the re-evaluations are completed, appropriate issues implementation of Order EA-12-049 will be entered into the corrective action process were identified.

and addressed.

2 Flood re-evaluations pursuant to the 10 CFR Completed. Reference 6 submitted 50.54(f) letter of March 12, 2012 are not completed the Flood re-evaluation to the NRC.

and therefore not assumed in this submittal. As the No issues impacting the re-evaluations are completed, appropriate issues implementation of Order EA-12-049 will be entered into the corrective action process were identified.

and addressed.

3 Implement revisions to emergency operating Completed procedures (EOPs) identified by the BWROG to extend operation of steam driven pumps for core coolinQ durinQ ELAP.

4 Validate implementing procedures can be Completed performed in a timely manner.

5 Final plant specific analysis for an ELAP will be Completed performed with equivalent acceptance criteria with the exception of Condensate Storage Tank (CST) inventory and suppression pool level which will be altered in recognition of the external hazards, and revised duration of the mitigating strategies.

6 Phase 3 activities will ensure adequate inventory of Completed water can be provided directly from the Cedar River or other sources independent of the normal River Water Supply pumps.

7 Implement new and revised plant procedures for Started FLEX Strategies.

8 Implement administrative controls for the FLEX Started Program.

9 Procure FLEX portable equipment. Started 10 Establish preventive maintenance and testing of Started FLEX portable equipment.

11 Revise UFSAR and TRM as needed to reflect FLEX Not started proqram.

12 Complete training of applicable personnel. Started Page 3 of 8

Overall Integrated Plan Pending Actions Status 13 Establish "Playbook" for Regional Response Center Started interface with the NextEra Energy Duane Arnold.

14 Review generic BWROG analysis of FLEX Completed implementation and perform a detailed review of suppression pool temperature to support FLEX strateQies.

15 Perform analysis of final load shedding strategy for Completed essential station batteries and implement in plant procedures.

16 Modify the plant to establish a flood staging area for Started portable equipment.

17 Evaluate deployment routes for portable equipment. Completed 18 Modify the plant to facilitate connection of portable Started. Detail design has power supplies. This will include connection points concluded the preferred connection for a 480 volt generator to essential battery point is at 18032.

chargers and 48Q volt distribution panel 1803.

Quick connection points will be established for 120 volt AC power to instrument power supplies.

19 Modify the plant to add suction and injection Started. The proposed modification connection points for portable pump. The portable is revised to allow access to the Main pump suction will allow access to;the-eirculating Turbine Condenser System hot well water pit (Pump House) from a protected area rather than the circulating water pit (Turbine Building) during a design bases flood. The during a design bases flood.

injection point will provide a redundant connection point for RPV makeup located in a protected area (Reactor BuildinQ).

20 Construct two FLEX portable equipment storage Completed buildings. The buildings will be separated to minimize the potential for a single tornado path to interact with both buildings.

21 Phase 3 activities will ensure essential bus can be Started.

re-powered using a portable 4160 V Generator. Procedures will direct the connection This will include a modification that establishes a of the 4160 VAC generator to the transfer panel (disconnect switch) installed in the Standby Transformer secondary or turbine building that provides a location for the essential bus feeder lines. This connection during a design bases flood and will supply power to one or both procedures for mobilization. essential 4160 VAC buses.

22 Procedures will provide for opening containment Procedures currently exist but will be vent valves using portable pneumatic supply. reviewed in association with modification development under Order EA-13-109.

23 Modify the plant to establish a manual vent Completed capability for the reactor building near the spent fuel pool.

24 Update analysis of room heat-up during an ELAP. Started 25 Screen BWROG RCIC Durability Study for Started extending RCIC operation during an ELAP and make applicable improvements.

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Overall Integrated Plan Pending Actions Status 26 Establish methods to recharge communications Completed equipment.

27 Establish methods to re-fuel portable equipment. Started 28 Review generic BWROG analysis of FLEX Completed implementation and perform a detailed review of limitations on SRV operation to support FLEX strategies.

29 If FLEX transport paths are over previously un- Completed excavated ground, review path for potential soil liquefaction during a seismic event.

Item Interim Staff Evaluation Open and Confirmatory Status Number Items 3.1, 1.4.A Off-Site Resources - Confirm the location of the local Completed staging area for the RRC equipment, and that access routes to the site, the method of transportation, and the drop off area have been properly evaluated for all applicable hazards.

3.1.2.A Confirm the actual flood hazard level for which Completed. Reference 6 reasonable protection and a means to deploy the submitted the Flood re-portable equipment is to be provided. evaluation to the NRG. No issues impacting the implementation of Order EA-12-049 were identified.

3.1.3.1.A Confirm that the separation of the two FLEX Completed equipment storage buildings is sufficient to reasonably ensure that one set of equipment will be available, accounting for local tornado data (speed and direction), the actual separation distance of the buildings, and the axis between them.

3.2.1.1.A From the June 2013, position paper (ADAMS Completed Accession No. ML13190A201 ), as discussed in the NRG endorsement letter dated October 3, 2013 (ADAMS Accession No. ML13275A318), confirm that benchmarks are identified and discussed which demonstrate that the Modular Accident Analysis Program (MAAP) 4 is an appropriate code for the simulation of an ELAP event at Duane Arnold.

3.2.1.1.B Confirm that the collapsed vessel level in the MAAP4 Completed analysis remains above Top of Active Fuel (TAF) and the cool down rate is within technical specification limits.

3.2.1.1.C Confirm that MAAP4 is used in accordance with Completed Sections 4.1, 4.2, 4.3, 4.4, and 4.5 of the June 2013, position paper.

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Item Interim Staff Evaluation Open and Confirmatory Status Number Items 3.2.1.1.D Confirm that in using MAAP4, the subset of key Completed modeling parameters cited from Tables 4-1 through 4-6 of the "MAAP4 Application Guidance, Desktop Reference for Using MAAP4 Software, Revision 2" (Electric Power Research Institute Report 1020236) is justified. This should include response at a plant-specific level regarding specific modeling options and parameter choices for key models that would be expected to substantially affect the ELAP analysis performed for that licensee's plant. Parameters considered important in the simulation of the ELAP event by the vendor/licensee include nodalization, general two-phase flow modeling, modeling of heat transfer and losses, choked flow, vent line pressure losses, and decay heat.

3.2.1.1.E Confirm that the specific MAAP4 analysis case that Completed was used to validate the timing of the mitigating strategies in the Integrated Plan is identified.

Alternately, a comparable level of information may be included in the supplemental response.

3.2.1.3.A The licensee plans to revise its procedures to be Completed consistent with the BWROG recommendations- for extending the availability of steam-driven core cooling systems. Confirm that the technical justification for the recommendations is applicable to DAEC.

3.2.1.8.A Confirm that the two portable diesel-driven pumps Completed sized in accordance with 10 CFR 50.54(hh)(2) requirements will have sufficient capability to be used as credited in the FLEX strategies implemented pursuant to Order EA-12-049.

3.2.3.A Confirm that the DAEC implementation of BWROG Completed EPG/ SAG, Revision 3, including any associated plant-specific evaluations, is completed in accordance with the provisions of the NRC endorsement letter dated January 9, 2014.

3.2.4.2.A Confirm that the updated analyses of room heat-up Completed (and any supporting actions) ensure that adequate cooling is provided to equipment needed during an ELAP event.

3.2.4.2.B

• Confirm that any equipment in the reactor building Completed needed for ELAP mitigation during Phases 2 or 3 will not be compromised by the steam environment caused by SFP boiling.

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Item Interim Staff Evaluation Open and Confirmatory Status Number Items 3.2.4.4.A The NRC staff has reviewed the licensee Completed communications assessment (ADAMS Accession No. ML12307A120) and has determined that the assessment and planned upgrades are reasonable (ADAMS Accession No. ML13142A320). Confirm that the upgrades to the site's communications systems have been completed.

3.2.4.6.A Confirm that DAEC's plan addresses accessibility and Completed habitability of all plant areas requiring personnel access in sufficient detail to determine if the environmental conditions support the needed operator actions.

3.2.4.7.A Confirm that the potential effects of using river water, Completed which may contain suspended solids, for reactor/SFP cooling are addressed.

3.2.4.9.A Confirm that a refueling strategy for FLEX equipment Completed has been developed based on a plant-specific analysis. The confirmation should include delivery capabilities, including for an indefinite coping period, and how fuel quality will be assured, if stored for extended periods (including fuel contained in the fuel tanks of Phase 2 equipment).

3:2.4.10.A Confirm that the final load shedding analysis has been Completed completed and that the time constraints assumed in the mitigating strategies have been validated, based on the results of that analysis (DAEC Open Action Item 15).

3.4.A Offsite resources - Confirm that NEI 12-06, Section Completed 12.2 guidelines 2 through 10, regarding minimum capabilities for offsite resources, have been adequately addressed.

7. Potential Interim Staff Evaluation Impacts There are no potential impacts to the Interim Staff Evaluation identified at this time.

8. References

1) Order EA-12-049, "Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events," dated March 12, 2012 (ML12056A045)

2) Letter, R. Anderson (NextEra Energy Duane Arriold, LLC) to U.S. NRC, "NextEra Energy Duane Arnold, LLC's 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)," NG-13-0084, dated February 28, 2013 (ML13063A148)

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3) Letter, T.A. Vehec (NextEra Energy Duane Arnold, LLC) to U.S. NRG, "NextEra Energy Duane Arnold Energy Center, LLC's 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)" NG-14-0200, dated August 25, 2014 (ML14239A493)

4) NRG Order EA-13-109, "Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions," dated June 6, 2013. (ML13143A321)

5) Letter, R. Anderson (NextEra Energy Duane Arnold, LLC) to U.S. NRG "NextEra Energy Duane Arnold, LLC Seismic Hazard and Screening Report (CEUS Sites),

• Response to NRG Request for Information Pursuant to 10 CFR 50.54(f)

Regarding Recommendation 2.1 of Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident" (NG-14-0092),dated March 28, 2014 (ML14092A331)

6) Letter, R. Anderson (NextEra Energy Duane Arnold, LLC) to U.S. NRG "Response to NRG Request for Information Pursuant to 10CFR 50.54(f)

Regarding Recommendation 2.1, Flooding. Of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident; Flood Hazard Reevaluation Report" (NG-14-'-0076), dated March 10, 2014(ML14072A019)

7) Letter, T. A. Vehec (NextEra Energy Duane Arnold, LLC) to U.S. NRG, "NextEra Energy Duane Arnold Energy Center, LLC's 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)" (NG"'" 15-0032, dated February 19, 2015 (ML15054A006)

8) Letter, T. A. Vehec (NextEra Energy Duane Arnold, LLC) to U.S. NRG, "NextEra Energy Duane Arnold Energy Center, LLC's 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)" (NG-15-0260, dated August 14, 2015 (ML15246A409)

9) Letter, T. A. Vehec (NextEra Energy Duane Arnold, LLC) to U. S. NRG, "NextEra Energy Duane Arnold Energy Center, LLC's 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)" (NG-16-0049, dated February 29, 2016 (ML16064A023)

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