0CAN041410, Revised Response to NRC 10 CFR 50.54(f) Request for Information Regarding Near-Term Task Force (NTTF) Recommendation 2.3, Flooding

Revised Response to NRC 10 CFR 50.54(f) Request for Information Regarding Near-Term Task Force (NTTF) Recommendation 2.3, Flooding

ML14120A494
Person / Time
Site:	Arkansas Nuclear
Issue date:	04/30/2014
From:	Browning J G Entergy Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
0CAN041410
Download: ML14120A494 (7)

Text

0CAN041410April 30, 2014U.S. Nuclear Regulatory CommissionATTN: Document Control Desk11555 Rockville PikeRockville, MD 20852

SUBJECT:

Revised Response to NRC 10 CFR 50.54(f) Request for Information RegardingNear-Term Task Force (NTTF) Recommendation 2.3, FloodingArkansas Nuclear One - Units 1 and 2 Docket Nos. 50-313 and 50-368License Nos. DPR-51 and NPF-6

REFERENCES:

1. NRC Letter to Entergy,Request for Information Pursuant to10 CFR 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3 of theNTTF Review of Insights from the Fukushima Dai-ichi Accident

,March 12, 2012 (ML12053A340) (0CNA031208)2. Entergy Letters to NRC,Flooding Walkdown Report - Entergy'sResponse to NRC Request for Information Pursuant to 10 CFR 50.54(f)Regarding the Flooding Aspects of Recommendation 2.3 of the NTTFReview of Insights from the Fukushima Dai-ichi Accident , datedNovember 27, 2012, (ML12334A008 and ML12334A006) (1CAN111202 and 2CAN111202)3. NRC Letter to Entergy,Request for Additional Information (RAI)Associated with NTTF Recommendation 2.3, Flooding Walkdowns , datedDecember 23, 2013 (ML13325A891) (0CNA121304)4. Entergy Letter to NRC,Update to Response to NRC 10 CFR 50.54(f)Request for Information Regarding NTTF Recommendation 2.3, Flooding- Review of Available Physical Margin (APM) Assessments, datedJanuary 31, 2014 (ML14031A183) (0CAN011404)

Dear Sir or Madam:

On March 12, 2012, the NRC staff issued Reference 1 requesting information pursuant toTitle 10 of the Code of Federal Regulations 50.54(f) which contains specific RequestedInformation associated with NTTF Recommendation 2.3 for Flooding. By Reference 2, EntergyOperations, Inc. (Entergy) initially submitted the Flooding Walkdown Reports for ArkansasNuclear One (ANO).Entergy Operations, Inc.

1448 S.R. 333Russellville, AR 72802Tel 479-858-3110Jeremy G. BrowningSite Vice PresidentArkansas Nuclear One 0CAN041410 Page 2 of 2The NRC issued RAIs concerning APM by Reference 3. By Reference 4 Entergy committed torespond to the APM RAIs and provide revised Flooding Walkdown Reports by April 30, 2014.The flooding walkdowns have been completed; however, additional time is needed to compilethe results and finalize the reports; therefore, Entergy will provide the revised FloodingWalkdown Reports by May 15, 2014. In accordance with Entergy's commitment managementprocedure, the NRR Project Manager was notified of the delay on April 29, 2014. Attachment 1provides responses to the APM RAIs.This letter contains a new regulatory commitment which is identified in Attachment 2. Shouldyou have any questions regarding this submittal, please contact Stephenie Pyle at 479.858.4704.I declare under penalty of perjury that the foregoing is true and correct. Executed onApril 30, 2014.

Sincerely,Original signed by Jeremy G. Browning JGB/nbmAttachments: 1. Responses to APM RAIs for ANO2. List of Regulatory Commitmentscc: Mr. Marc L. DapasRegional AdministratorU. S. Nuclear Regulatory Commission, Region IV1600 East Lamar BoulevardArlington, TX 76011-4511NRC Senior Resident Inspector Arkansas Nuclear OneP.O. Box 310London, AR 72847U. S. Nuclear Regulatory CommissionAttn: Mr. Peter Bamford MS O-8B3One White Flint North11555 Rockville PikeRockville, MD 20852 to0CAN041410Responses to Available Physical Margin (APM) Requests for AdditionalInformation (RAIs) for Arkansas Nuclear One (ANO) to 0CAN041410 Page 1 of 2Responses to APM RAIs for ANORAI 1: Provide confirmation that the process for evaluating APM was reviewed.Entergy Operations, Inc. has completed a review of the process used at ANO-1 and ANO-2 toevaluate APMs.RAI 2: Provide confirmation that the APM process is now or was always consistent withthe guidance in Nuclear Energy Institute (NEI) 12-07 and discussed in this RAI.The original walkdown effort intended to follow the guidance provided in NEI 12-07. For thesubsequent walkdown effort, additional actions have been taken to make the processconsistent with the information provided in this RAI including the definition of small margin.RAI 3: If changes are necessary, a general description of any process changes toestablish this consistency.As stated above, the original walkdown effort intended to follow the guidance provided inNEI 12-07; however, discrepancies were identified in the original walkdown reports. As a resulta subsequent walkdown effort has been performed, and APM is being documented. For thesubsequent walkdown effort, the definition for a small margin was updated to be consistent withthe information provided in this RAI.RAI 4: As a result of the audits and subsequent interactions with industry during publicmeetings, NRC staff recognized that evaluation of APM for seals (e.g., flood doors,penetrations, flood gates, etc.) was challenging for some licensees. Generally, licenseeswere expected to use either Approach A or Approach B (described below) to determinethe APM for seals:a) If seal pressure ratings were known, the seal ratings were used to determine APM(similar to example 2 in Section 3.13 of NEI 12-07). A numerical value for APMwas documented. No further action was performed if the APM value was greaterthan the pre-established small-margin threshold value. If the APM value wassmall, an assessment of "significant consequences" was performed and theguidance in NEI 12-07 Section 5.8 was followed.b) If the seal pressure rating was not known, the APM for seals in a flood barrier isassumed to be greater than the pre-established small-margin threshold value ifthe following conditions were met: (1) the APM for the barrier in which the seal islocated is greater than the small-margin threshold value, and there is evidencethat the seals were designed/procured, installed, and controlled as flooding sealsin accordance with the flooding licensing basis. Note that in order to determinethat the seal has been controlled as a flooding seal it was only necessary todetermine that the seal configuration has been governed by the plant's design to 0CAN041410 Page 2 of 2control process since installation. In this case, the APM for the seal could havebeen documented as "not small."As part of the RAI response, state if either Approach A or Approach B was used as partof the initial walkdowns or as part of actions taken in response to this RAI. No additionalactions are necessary if either Approach A or B was used.If neither Approach A or B was used to determine the APM values for seals (either aspart of the walkdowns or as part of actions taken in response to this RAI), then performthe following two actions:Enter the condition into the Corrective Action Program (CAP) (note: it isacceptable to utilize a single CAP entry to capture this issue for multiple seals).CAP disposition of "undetermined" APM values for seals should consider theguidance provided in NEI 12-07, Section 5.8. The CAP disposition should confirmall seals can perform their intended safety function against floods up to thecurrent licensing basis flood height. Disposition may occur as part of theIntegrated Assessment. If an Integrated Assessment is not performed, determinewhether there are significant consequences associated with exceeding thecapacity of the seals and take interim action(s), if necessary, via the CAPprocesses. These actions do not need to be complete prior to the RAI response.Report the APM as "undetermined" and provide the CAP reference in the RAI response.Approach A is being used to determine APM if seal pressure ratings are known; Approach B isbeing used to determine APM for seals if seal pressure ratings are not known. When the sealpressure rating is not known, the APM for these seals is assumed to be greater than thepre-established small-margin threshold value. The conditions described above are being metbecause the APM for the barrier in which the seal is located is greater than the small-marginthreshold value, and the seals were designed, procured, and installed in accordance with theANO licensing basis. The seals are being inspected as part of the walkdowns for signs ofdegradation, and corrective actions are being taken, when required. to0CAN041410List of Regulatory Commitments to 0CAN041410 Page 1 of 1List of Regulatory CommitmentsThe following table identifies those actions committed to by Entergy Operations, Inc. (Entergy)in this document. Any other statements in this submittal are provided for information purposesand are not considered to be regulatory commitments.COMMITMENT TYPE(Check One)

SCHEDULEDCOMPLETIONDATE(If Required)

ONE-TIMEACTIONCONTINUINGCOMPLIANCEProvide revised Flooding Walkdown Reports XMay 15, 2014