ML15071A141

Relief Request No. VRR-RBS-2014-1 Regarding the Third 10-Year Inservice Testing Interval

ML15071A141
Person / Time
Site:	River Bend
Issue date:	03/23/2015
From:	Meena Khanna, Wang A Plant Licensing Branch IV
To:	Entergy Operations
Wang A, NRR/DORL/LPL4-2, 415-1445
References
TAC MF4125
Download: ML15071A141 (8)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 March 23, 2015 Vice President, Operations Entergy Operations, Inc.

River Bend Station 5485 US Highway 61 N St. Francisville, LA 70775

SUBJECT:

RIVER BEND STATION, UNIT 1 - RELIEF REQUEST NO. VRR-RBS-2014-1 REGARDING THE THIRD 10-YEAR INSERVICE TESTING INTERVAL (TAC NO. MF4125)

Dear Sir or Madam:

By letter dated May 14, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML14164A435), Entergy Operations, Inc. (Entergy, the licensee),

submitted relief requests VRR-RBS-2014-1 and VRR-RBS-2014-2 to the U.S. Nuclear Regulatory Commission (NRC). In a subsequent letter dated October 8, 2014 (ADAMS Accession No. ML14296A377), the licensee withdrew relief request VRR-RBS-2014-2. In relief request VRR-RBS-2014-1, the licensee proposed alternatives to certain inservice test (IST) requirements of the 2001 Edition through 2003 Addenda of the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code),

for the IST program at River Bend Station, Unit 1 (RBS), for the remainder of the third 10-year IST program interval.

Specifically, pursuant to Title 10 of the Code of Federal Regulations (10 CFR)

Section 50.55a(a)(3)(i), the licensee requested to use the proposed alternative in VRR-RBS-2014-1 on the basis that the alternative provides an acceptable level of quality and safety.

The paragraph headings in 10 CFR 50.55a were changed by Federal Register notice dated November 5, 2014 (79 FR 65776), which became effective on December 5, 2014 (e.g. 10 CFR 50.55a(a)(3)(i) is now 50.55a(z)(1 ), and 50.55a(a)(3)(ii) is now 50.55a(z)(2)).

See the cross-reference tables, which are cited in the notice at ADAMS Accession No. ML14015A191 and ADAMS Package Accession No. ML14211A050.

The NRC staff has reviewed the licensee's relief request and has determined that the requested alternative will provide an acceptable level of quality and safety, as documented in the enclosed safety evaluation. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(z)(1). Therefore, the NRC staff authorizes the use of Relief Request VRR-RBS-2014-1 for the remainder of the third 10-year IST program interval at RBS.

All other ASME OM Code requirements for which relief was not specifically requested and approved remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector.

The NRC staff's safety evaluation is enclosed. If you have any questions, please contact Alan Wang at 301-415-1445 or via e-mail at Alan.Wang@nrc.gov.

Sincerely,

'l'Y\~

Meena K. Khanna, Chief Plant Licensing Branch IV-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-458

Enclosure:

Safety Evaluation cc w/encl: Distribution via Listserv

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST VRR-RBS-2014-1 ASSOCIATED WITH THE THIRD 10-YEAR INSERVICE TESTING INTERVAL ENTERGY OPERATIONS, INC.

RIVER BEND STATION, UNIT 1 DOCKET NO. 50-458

1.0 INTRODUCTION

By letter dated May 14, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML14164A435), Entergy Operations, Inc. (Entergy, the licensee),

submitted relief requests VRR-RBS-2014-1 and VRR-RBS-2014-2 to the U.S. Nuclear Regulatory Commission (NRC) for review and approval. In a subsequent letter dated October 8, 2014 (ADAMS Accession No. ML14296A377), the licensee withdrew alternative request VRR-RBS-2014-2. In relief request VRR-RBS-2014-1, the licensee proposed alternatives to certain inservice test (IST) requirements of the 2001 Edition through 2003 Addenda of the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code), for the IST program at River Bend Station, Unit 1 (RBS), for the remainder of the third 10-year IST program interval.

Specifically, pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(a)(3)(i),

the licensee requested to use the proposed alternatives in VRR-RBS-2014-1 on the basis that the alternatives provide an acceptable level of quality and safety.

The paragraph headings in 10 CFR 50.55a were changed by Federal Register notice dated November 5, 2014 (79 FR 65776), which became effective on December 5, 2014 (e.g., 10 CFR 50.55a(a)(3)(i) is now 50.55a(z)(1 ), and 50.55a(a)(3)(ii) is now 50.55a(z)(2)). See the cross-reference tables, which are cited in the notice at ADAMS Accession No. ML14015A191 and ADAMS Package Accession No. ML14211A050. The remainder of this evaluation will therefore, reference the new regulations.

2.0 REGULATORY EVALUATION

The third 10-year IST interval at RBS began on December 2, 2007, and is scheduled to end on December 1, 2017. The applicable ASME OM Code edition and addenda for the third 10-year IST Interval at RBS is the 2001 Edition through the 2003 Addenda.

Enclosure

The regulations in 10 CFR 50.SSa(f), "lnservice Testing Requirements," require, in part, that IST of certain ASME Code Class 1, 2, and 3 components must meet the requirements of the applicable ASME OM Code and addenda, except where alternatives have been authorized, pursuant to 10 CFR 50.55a(z)(1) or 10 CFR 50.55a(z)(2).

In proposing alternatives, a licensee must demonstrate that the proposed alternatives provide an acceptable level of quality and safety as outlined in 10 CFR 50.55a(z)(1 ), or compliance would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety as outlined in 10 CFR 50.55a(z)(2).

Based on the above, the NRG staff finds regulatory authority exists for the licensee to request, and the NRG to authorize, the proposed alternatives to the ASME OM Code, subject to the evaluation given below.

3.0 TECHNICAL EVALUATION

The requested alternatives discussed below are requested for the remainder of the third 10-year IST interval at RBS which began on December 2, 2007, and are scheduled to end on December 1, 2017. The applicable ASME OM Code Edition and Addenda for RBS during the third 10-year IST interval is the 2001 Edition through the 2003 Addenda.

3.1 Applicable Code Requirements ASME OM Code, Mandatory Appendix I, paragraph l-1320(a), 5-Year Test Interval, specifies that Class 1 pressure relief valves shall be tested at least once every 5 years, starting with initial electric power generation. No maximum limit is specified for the number of valves to be tested within each interval; a minimum of 20 percent of the valves from each valve group shall be tested within any 24-month interval. This 20 percent shall consist of valves that have not been tested during the current 5-year interval, if they exist. The test interval for any individual valve shall not exceed 5 years.

3.2 ASME Code Components Affected

The licensee requested using alternative testing for the following Class 1, Crosby Model HB-65-DF Main Steam Safety/Relief Valves (SRVs):

B21-RVF041 A B21-RVF041 B B21-RVF041C B21-RVF041D B21-RVF041 F B21-RVF041 G B21-RVF041 L B21-RVF04 7A 821-RVF0478 B21-RVF047C B21-RVF047D B21-RVF047F B21-RVF051 B 821-RVF051C 821-RVF051D B21-RVF051G

3.3 Licensee's Reason for Request By letter dated May 14, 2014, the licensee stated, in part:

Component/System Function The Main Steam Safety/Relief (MSSR) System provides Reactor Pressure Vessel (RPV) overpressure protection and automatic depressurization of the Nuclear System by opening the SRVs.

Reason for Request

The Crosby Model HB-65-DF SRVs have shown exemplary test history at RBS, as [discussed] ... below. However, given the current 24-month operating cycle for RBS, Entergy Operation Incorporated (EOI) is required to remove and test fifty percent of the SRVs every refueling outage (i.e. eight of 16), so that all valves are removed and tested every two refueling outages. This ensures compliance with the ASME OM Code requirements for testing Class 1 pressure relief valves within a five-year interval. Approval of extending the test interval to 6 years with a grace period of 6 months would reduce the minimum number of SRVs tested at RBS over three refueling outages by eight.

The ASME Code committees have developed Code Case OMN-17, "Alternative Rules for Testing ASME Class 1 Pressure Relief/Safety Valves," which was published via ASME OM Code-2009 Edition. This Code Case has not been approved for use in US NRC Regulatory Guide 1.192, "Operation and Maintenance Code Case Acceptability, ASME OM Code, dated June 2003. The Code Case allows the Owner to extend the test frequencies for Class 1 pressure relief valves to a 72-month (6-year) test interval providing all the requirements of the Code Case are satisfied. The Code applicability specified in the Code Case is, in part, ASME OM Code 2001 Edition through the 2006 Addenda of Appendix I, Section 1-1320. This is consistent with the Interval Code of record for RBS.

RBS currently meets or exceeds all the requirements specified in Code Case OMN-17.

All SRVs are located in the upper elevations of the RBS Drywell. The major contributors to radiation exposure are the Main Steam Lines, including the SRVs, and the High Pressure/Low Pressure Core Spray lines passing through the area.

Removal of an installed SRV and installation of a replacement SRV requires installation of scaffolding, removal of insulation and various appurtenances on the SRV, and unbolting the SRV. Once unbolted, the SRV is maneuvered from its location and lowered to the grade elevation and transported through the drywell and containment equipment hatches. Each SRV weighs approximately 3000 pounds, and due to its size, a crew of five to seven personnel is necessary to safely move each valve.

Entergy has evaluated the historical cumulative radiation exposure at RBS for removal and replacement of SRVs from the last five RBS refueling outages. The work evolutions necessary to remove and replace these valves each refueling

years/72 months) would continue to provide an acceptable level of quality and safety while restoring the operational and maintenance flexibility that was lost when the 24-month fuel cycle created the unintended consequences of more frequent testing. This proposed alternative will continue to provide assurance of the valves' operational readiness and provides an acceptable level of quality and safety pursuant to [10 CFR 50.55a(z)(1 )].

This proposed relief request ... will establish a test interval that would enable EOI to maintain a Crosby Model HB-65-DF SRV in service for three operating cycles, while also allowing adequate time to transport, test, and refurbish SRVs at an external facility prior to reinstallation.

• 3.4 NRC Staff Evaluation The RBS SRVs are ASME Code Class 1 pressure relief valves that provide overpressure protection for the reactor coolant pressure boundary to prevent unacceptable radioactive release and exposure to plant personnel. ASME OM Code, Mandatory Appendix I requires that Class 1 pressure relief valves be tested at least once every 5 years. However, Mandatory Appendix I does not require that pressure relief valves be disassembled and inspected prior to the start of the 5-year test interval. In lieu of the 5-year test interval, the licensee proposed to implement ASME OM Code Case OMN-17, which allows a test interval of 6 years plus a 6-month grace period. The ASME Committee on OM developed Code Case OMN-17 and published it in the 2009 Edition of the ASME OM Code. ASME OM Code Case OMN-17 imposes a special maintenance requirement to disassemble and inspect each pressure relief/safety valve to verify that parts are free from defects, resulting from time-related degradation or service-induced wear, prior to the start of the extended test interval and at each required test during the interval. The purpose of this maintenance requirement is to reduce the potential for pressure relief valve set-point drift.

ASME OM Code Case OMN-17 has not yet been added to RG 1.192, "Operation and Maintenance Code Case Acceptability, ASME OM Code," or included in 10 CFR 50.55a by reference. However, the NRC has allowed licensees to use ASME OM Code Case OMN-17, provided all requirements in the Code Case are met. Consistent with the special maintenance requirement in ASME OM Code Case OMN-17, each SRV at RBS will be disassembled and inspected to verify that internal surfaces and parts are free from defects or service induced wear, prior to the start of the next test interval. This maintenance will also help to reduce the potential for setpoint drift, and increase the reliability of these SRVs to perform their design requirement functions. Consistent with the special maintenance requirement in ASME OM Code Case OMN-17, critical components will be inspected for wear and defects. This process is consistent with ASME OM Code Case OMN-17 paragraphs (d) and (e).

Furthermore, ASME OM Code Case OMN-17 is performance-based, in that it requires that the SRVs be tested more frequently if test failures occur. For example, ASME OM Code Case OMN-17 requires that two additional valves be tested when a valve in the initial test group exceeds the set pressure acceptance criteria. All remaining valves in the group are required to be tested if one of the additional valves tested exceeds its set pressure acceptance criteria.

Additionally, a review of recent setpoint testing results shows that RBS has had only one as-tound test failure since 2008 that exceeded the as-found acceptance criteria (+3%, -5%) and this failure was in the negative (or conservative) direction.

Based on the historical performance of the setpoint testing of the SRVs at RBS and the proposed disassembly and inspection of the SRVs prior to use, the NRC staff finds that implementation of ASME OM Code Case OMN-17 for the testing of the RBS SRVs, in lieu of the requirements of the 2001 Edition through the 2003 Addenda, Mandatory Appendix I, Section 1320 of the ASME OM Code, provides an acceptable level of quality and safety.

4.0 CONCLUSION

Based on the above, the NRG staff determined that the alternative testing, proposed by relief request VRR-RBS-2014-1, provides an acceptable level of quality and safety for the RBS SRVs.

Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(z)( 1) and is in compliance with the ASME OM Code requirements. Therefore, the NRG staff authorizes the use of alternative request VRR-RBS-2014-1 at RBS for the remainder of the third 10-year IST program interval.

All other ASME OM Code requirements for which relief was not specifically requested and approved remain applicable.

Principal Contributor: J. Billerbeck, NRR Date: March 23, 2015

All other ASME OM Code requirements for which relief was not specifically requested and approved remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector.

The NRC staff's safety evaluation is enclosed. If you have any questions, please contact Alan Wang at 301-415-1445 or via e-mail at Alan.Wang@nrc.gov.

Sincerely, IRA/

Meena K. Khanna, Chief Plant Licensing Branch IV-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-458

Enclosure:

Safety Evaluation cc w/encl: Distribution via Listserv DISTRIBUTION:

PUBLIC LPL4-2 R/F RidsAcrsAcnw_MailCTR Resource RidsNrrDeEpnb Resource RidsNrrDorllpl4-2 Resource RidsNrrLAPBlechman Resource RidsNrrPMRiverBend Resource RidsRgn4MailCenter Resource MWaters, EDO RIV JBillerbeck, NRR RidsNrrDorlDpr ADAMS Accession Nos.: ML15071A141 NRR-028 *via email OFFICE NRR/DORL/LPL4/PM NRR/DORL/LPL4-2/LA NRR/DE/EPNB/BC NRR/DORL/LPL4-2/PM NRR/DORL/LPL/4-2/BC NAME Tlamb PBlechman DAiiey* AWang MKhanna DATE 3/17/15 3/13/15 3/6/2015 3/19/15 3/23/15 OFFICIAL AGENCY RECORD