NG-15-0260, 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...

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...

ML15246A409
Person / Time
Site:	Duane Arnold
Issue date:	08/14/2015
From:	Vehec T NextEra Energy Duane Arnold
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-12-049, NG-15-0260
Download: ML15246A409 (11)

Text

ENERG Y

• OUANE ARNOLD August 14, 2015 NG-1 5-,0260 10 CFR 2.202 U. S. Nuclear ATTN: Document Regulatory ControlCommission Desk Washington, DC 20555-0001 Duane Arnold Energy Center Docket No. 50-3.31 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 Modifyingq Licenses with Reqard to Requlirements for Mitigation Strategies for Beyond-Desigin-Basis External Events (Order Number EA,-12-049)

References:

1) .Order EA-12-.049, Requirements "Order Modifying for Mitigation Licenses Strategies with Regard to for Beyond-Design-Basis External Events," dated March 12, 2012 (ML.12056A045)

2) Letter, R. Anderson (NextEra Energy Duane Arnold, LLC) to U. S. NRC, "NextEr'a Energy Duane Arnold, LLC's Overall Integqrated Plan in Response to March 12. 2012 Commission Order Modifyingq Licenses with Regard to Reguirements for Mitigqation 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 Arnold). In Reference 2, NextEra En~ergy Duane A~rnold 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.

A t6/

NextEra Energy Duane 'Arno1d, ILC, 3277 DAEC Road, Palo, IA5.2324 A , _, ,_, /'J /

CW\ ~

Document Control Desk NG-1 5-0260 Page 2 of 2 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, ifany.

Ideclare under penalty of perjury that the foregoing is true and correct.

xeutidon August 14, 2015.

T. A. Vehec Vice President, Duane Arnold Energy Center NextEra Energy Duane Arnold, LLC Enclosure cc: Regional Administrator, USNRC, Region III Resident Inspector, USNRC, Duane Arnold Energy Center Project Manager, USNRC, Duane Arnold Energy Center

Attachment to NG-I15-0260 NextEra Energqy.Duane Arnold. LLC's Six Month Status Report for the Implementation .ofOrder EA-12-049. Order Modifying Licenses with Regard to Requirements for Mitigation Strateqies 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 7), and are current as of July 31, 2015.

• Submit 6 month status report

• FLEX Storage Buildings Completed

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.

Target Revised Mieson Cmpeton Activity Target DattoeCopeto Status Completion Date Date Submit Overall Integrated Implementation Plan February 2013 Completed N/A Submit 6 Month Status Report August 2013 Completed N/A Complete Revision to Emergency Operating Procedures to Extend Completed Operation of Steam Driven Pumps December 2013 January 2014 N/A Submit 6 Month Status Report February 2014 Completed N/A Complete Regional Response Center Arrangements December 2015 Started N/A Submit 6 Month Status Report August 2014 Completed N/A First Refueling Outage of RFO 24 Implementation Period (Fall 2014) Completed NIA Page 1 of 8

Target Activity Revised Target Milestone Completion Status Completion Date Date Complete S;ite Specific Analysis of NEDC-337..71.p.Rev. 1 January 2015 Coplted N/A Submit 6 Month Status Report Febuay 205 Completed N/A FLEX Storage Buildings Cornpleted March 2015 .Cornpleted N/A Dec. 2015 Primary portable equipment is on site, procurement of remaining Identified Portable Equipment Stored on equipment is Site May 2015 Started underway.

Submit 6 Month Status Report August 2015 Completed N/A Issue Modification Packages December 2015 Started N/A Submit 6 Month Status Report February 2016 Not Started N/A Complete Staffing Study for Flex Implemen~tation May 2016 Not Started N/A Validate that time sensitive actions can be completed consistent with the Flex Strategies August 2016 Not Started N/A Complete Implementing Procedure DeeomntadVliainAugust 2016 Started N/A Submit 6 Month Status Report August 2016 Not Started N/A 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 NIA

4. Changes to Compliance Method In addition to changes in compliance methods described in the previous six month update (Reference 7), the following new change to the compliance strategy was identified during this period:

In the original DAEC Overall Integrated Plan (OIP) (Reference 2) for implementation of NRC Order EA-12-049, a new suction line was planned for installation as buried piping between the circulating water pit in the pump house and the turbine building to allow staging of a portable pump inside the flood protected area of the turbine building (QIP Action 19) while still drawing water from the circulating water pit. In preparing the detailed design and construction planning for this modification, it was identified that underground interferences would make routing of this pipe difficult. An alternative source of high quality water that would be available, and as effective, during a flood is the Main Turbine Condenser System hot well. Duane Arnold Energy Center is Page 2 of 8

modifying its OIPpiping installing buried to usebetween a connection pointhouse the pump for suction from and the the hot turbine well rather than building.

'The DAEC OIP describes the strategy for Phase 2 to maintain core cooling using portable equipment. Under the modification section of this description it states: A buried 8" suction pipe will be routed from Pump House to the south wall of the mi/lup door in Turbine Building (Attachment 7)(Action 19). This section is revised to reflect that a buried suction pipe will not be installed. of the DAEC OIP provides a sketch of the injection path to the reactor pressure vessel that includes a reference to an 8 inch buried pipe. This sketch is revised to delete the reference to buried piping and reflect use of the hotwell as a water source. Attachment 12 of the DAEC QIP provides a list of implementation action items of which, Action 19 describes the modification as: The portablepump suction will allow access to the circulatingwater pit (Pump House) from a protected area (Turbine Building) during design bases flood. The modification description is revised to eliminate-reliance on this suction path and instead establish a hot well connection point. For scenarios other than external flood, the pump house circulating water pit will remain available as a source of water for reactor vessel injection. Underground piping is not needed for these scenarios since the yard remains suitable for laying of temporary fl~ibl*-h-~ose-Stwee the pump house n-dTeactor-building: _

5. Need for Relief/Relaxation and Basis for the RelieflRelaxation 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 ISeismic 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-1 2-049 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 cooling during ELAP. ________________

Page 3 of 8

N Overall Integrated Plan Pending Actions Status 4 Validate implementing procedures can be Not Started 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 Started 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 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 program.

12 Complete training of applicable personnel. Started 13 Establish '=Playbook" for Regional Response Center Started interface with the NextEra Energ Duane Arnold. ________________

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

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. Not started 18 Modify the plant to facilitate connection of portable Started. Detail design has concluded power supplies. This will include connection points the preferred connection point is at for a 480 volt generator to essential battery 1B032.

chargers and 480 volt distribution panel 1B03.

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 is connection points for portable pump. The portable revised to allow access to the Main pump suction will allow access to the circulating 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 Building). ________________

Page 4 of 8

Overall Integrated Plan Pending Actions Status 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. Detail design has concluded re-powered using a portable 4160 V Generator, a temporary connection into an This will include a modification that establishes a existing breaker to allow ready transfer panel (disconnect switch) installed in the connection of the portable generator turbine building that provides a location for to station 4160 Volt distribution connection during a design bases flood and provides a more flexible option.

procedures for mobilization.

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-1 3-109.

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

24 Update analysis of room heat-up during an ELAP. No~t started 25 Screen BWROG RCIC Durability Study for Started extending RCIC operation during an ELAP and make applicable improvements.

26 Establish methods to recharge communications Completed equipment.

27 Establish methods to re-fuel portable e uipment. 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 Iiquefaction during a seismic event. ________________

Numer Interim Staff Evaluation Open and Confirmatory Items Status 3.1.1 .4.A Off-Site Resources - Confirm the location of the local Started 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.__________

Page 5 of 8

Item Number Interim Staff Evaluation Open and Confirmatory Items Status 3.1.2.A Confirm the actual flood hazard level for which reasonable Completed.

protection and.a means to deploy the portable equipment Reference 6 is to be provided. submitted the Flood re-evaluation to the NRC. No issues impacting the implementation of Order EA-12-049

______________________________________were identified.

3.1.3.1 .A Confirm that the separation of thle two FLEX equipment Completed 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 Accession Completed No. ML13190A201), as discussed in the NRC endorsement letter dated October 3, 2013 (ADAMS Accession No. ML I13275A31 8), 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 Sections Completed 4.1, 4.2, 4.3, 4.4, and 4.5 of the June 2013, position 3.2.1.1.D Confirm that in using MAAP4, the subset of key modeling Completed 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 1 020236) 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 vendorllicensee 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 spec~ific MAAP4 analysis case that was Completed 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.__________

Page 6 of 8

Item Nubr Interim Staff Evaluation Open and Confirmatory Items Status 3.2.1.3.A The licensee plans to revise its procedures to be Started 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 sized in Started 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 _________ 049.

3.2.3.A Confirm that the DAEC implementation of BWROG EPG/ Started 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 (and Not Started any supporting actions) ensure that adequate cooling is

________ rovided to equipment needed during an ELAP event.

3.2.4.2.B Confirm that any equipment in the reactor building needed Not Started for ELAP mitigation during Phases 2 or 3 will not be compromised by the steam environment caused by SFP

_____ ____ boiling._ _ _ _ _ _ _ _ _ _

3.2.4.4.A The NRC staff has reviewed the licensee communications Completed assessment (ADAMS Accession No. ML12307A120) and has determined that the assessment and planned upgrades are reasonable (ADAMS Accession No. ML I13142A320). 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 Not Started habitability of all plant areas requiring personnel access in sufficient detail to deterrmine 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/SEP cooling are addressed.

3.2.4.9.A Confirm that a refueling strategy for FLEX equipment has started 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 12.2 Started gUidelines 2 through 10, regarding minimum capabilities for offsite resources, have been adequately addressed. __________

Page 7 of 8

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-1 2-049, "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)

3) Letter, T.A. Vehec (NextEra Energy Duane Arnold, LLC) to U. S. NRC, "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) NRC Order EA-1 3-109, "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. NRC "NextEra Energy Duane Arnold, LLC Seismic Hazard and Screening Report (CEUS Sites),

Response to NRC 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. NRC "Response to NRC 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. NRC, "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)

Page 8 of 8