ML22227A068
| ML22227A068 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 09/02/2022 |
| From: | David Wrona Plant Licensing Branch II |
| To: | Haaf T Duke Energy Progress |
| Mahoney M | |
| References | |
| EPID L-2022-LLR-0041 | |
| Download: ML22227A068 (13) | |
Text
September 2, 2022 Mr. Thomas Haaf Site Vice President Shearon Harris Nuclear Power Plant 5413 Shearon Harris Road Mail Code NHP01 New Hill, NC 27562-9300
SUBJECT:
SHEARON HARRIS NUCLEAR POWER PLANT, UNIT 1 - ALTERNATIVE TO CERTAIN INSERVICE TESTING REQUIREMENTS IN THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS CODE FOR OPERATION AND MAINTENANCE FOR CERTAIN TARGET ROCK SOLENOID VALVES (EPID L-2022-LLR-0041)
Dear Mr. Haaf:
The U.S. Nuclear Regulatory Commission (NRC) has approved your use of an alternative to certain inservice testing (IST) requirements in the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code) for the Shearon Harris Nuclear Power Plant, Unit 1 (Harris or HNP). This action is in response to your request HNP-IST-004-RR1, dated April 7, 2022, as supplemented by letter dated June 10, 2022 (Agencywide Documents Access and Management System (ADAMS) Accession Nos.
ML22097A150 and ML22161A056, respectively).
Specifically, pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(z)(1), the licensee requested to use an alternative on the basis that the proposed alternative provides an acceptable level of quality and safety.
The NRC staff has concluded that the proposed alternative HNP-IST-004-RR1 provides an acceptable level of quality and safety when implemented to establish performance-based leak testing intervals for the valves at Harris listed in the attached safety evaluation where those valves have demonstrated successful leak-test performance during the two most recent periodic leak tests. Accordingly, the NRC staff concludes that the licensee has adequately addressed all the regulatory requirements set forth in 10 CFR 50.55a(z)(1).
Therefore, the NRC staff authorizes the use of alternative HNP-IST-004-RR1 at Harris for the remainder of the Fourth 10-Year IST Program interval, which began on May 2, 2017, and is scheduled to end on April 30, 2027.
All other ASME Boiler and Pressure Vessel (BPV) Code or OM Code requirements for which an alternative was not specifically requested and approved remain applicable.
If you have any questions, please contact the Harris, Project Manager, Michael Mahoney at 301-415-3867 or via email at Michael.Mahoney@nrc.gov.
Sincerely, David J. Wrona, Chief Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-400
Enclosure:
Safety Evaluation cc: Listserv David J.
Wrona Digitally signed by David J. Wrona Date: 2022.09.02 08:57:53 -04'00'
Enclosure SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REQUEST HNP-IST-004-RR1 - ALTERNATIVE TO CERTAIN INSERVICE TESTING REQUIREMENTS IN THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS CODE FOR OPERATION AND MAINTENANCE FOR CERTAIN TARGET ROCK SOLENOID VALVES DUKE ENERGY PROGRESS, LLC SHEARON HARRIS NUCLEAR POWER PLANT, UNIT 1 DOCKET NO. 50-400
1.0 INTRODUCTION
By letter RA-22-0117 dated April 7, 2022 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML22097A150), as supplemented by a letter RA-22-0172 dated June 10, 2022 (ML22161A056), Duke Energy Company (the licensee) submitted proposed alternative request HNP-IST-004-RR1 to the U.S. Nuclear Regulatory Commission (NRC) for the use of an alternative to certain inservice testing (IST) requirements in the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code) at Shearon Harris Nuclear Power Plant, Unit 1 (Harris).
Specifically, pursuant to paragraph (z)(1) in Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities, Section 50.55a, Codes and standards, the licensee requested to use proposed alternative request HNP-IST-004-RR1 during the Fourth 10-Year IST Program interval to extend the testing interval for certain Target Rock solenoid-operated valves at Harris, on the basis that the proposed alternative will provide an acceptable level of quality and safety. Although the licensee referred to this submittal as a relief request, this submittal represents an alternative request in accordance with 10 CFR 50.55a(z)(1).
The NRC staff review of alternative request HNP-IST-004-RR1 for Harris is described in this safety evaluation (SE).
2.0 REGULATORY EVALUATION
The NRC regulations in 10 CFR 50.55a(f)(4), Inservice testing standards requirement for operating plants, state that throughout the service life of a boiling or pressurized water-cooled nuclear power facility, pumps and valves that are within the scope of the ASME OM Code must meet the IST requirements (except design and access provisions) set forth in the ASME OM Code and addenda that become effective subsequent to editions and addenda specified in 10 CFR 50.55a(f)(2) and (3) and that are incorporated by reference in 10 CFR 50.55a(a)(1)(iv),
to the extent practical within the limitations of design, geometry, and materials of construction of the components. The IST requirements for pumps and valves that are within the scope of the ASME OM Code but are not classified as ASME Boiler and Pressure Vessel Code (BPV Code)
Class 1, Class 2, or Class 3 may be satisfied as an augmented IST program in accordance with 10 CFR 50.55a(f)(6)(ii) without requesting relief under 10 CFR 50.55a(f)(5) or alternatives under 10 CFR 50.55a(z). This use of an augmented IST program may be acceptable provided the basis for deviations from the ASME OM Code, as incorporated by reference in 10 CFR 50.55a, demonstrates an acceptable level of quality and safety, or that implementing the Code provisions would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety, where documented and available for NRC review.
In proposing an alternative to IST requirements in the applicable edition or addenda of the ASME OM Code as incorporated by reference in 10 CFR 50.55a, a licensee must demonstrate that (1) the proposed alternative provides an acceptable level of quality and safety in accordance with 10 CFR 50.55a(z)(1), or (2) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety in accordance with 10 CFR 50.55a(z)(2).
The NRC regulations in 10 CFR Part 50, Appendix J, Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors, Option A, Prescriptive Requirements, in Section II, Explanation of terms, state in part the following:
H. Type C Tests means tests intended to measure containment isolation valve [CIV]
leakage rates. The containment isolation valves included are those that:
- 1. Provide a direct connection between the inside and outside atmospheres of the primary reactor containment under normal operation, such as purge and ventilation, vacuum relief, and instrument valves.
- 2. Are required to close automatically upon receipt of a containment isolation signal in response to controls intended to effect containment isolation.
- 3. Are required to operate intermittently under post accident conditions; and
- 4. Are in main steam and feedwater piping and other systems which penetrate containment of direct-cycle boiling water power reactors.
Option B, Performance-Based Requirements, in 10 CFR Part 50, Appendix J, states in Section I, Introduction, the following:
One of the conditions required of all operating licenses and combined licenses for light-water-cooled power reactors as specified in §50.54(o) is that primary reactor containments meet the leakage-rate test requirements in either Option A or B of this appendix. These test requirements ensure that (a) leakage through these containments or systems and components penetrating these containments does not exceed allowable leakage rates specified in the technical specifications; and (b) integrity of the containment structure is maintained during its service life. Option B of this appendix identifies the performance-based requirements and criteria for preoperational and subsequent periodic leakage-rate testing.
Specific guidance concerning a performance-based leakage-test program, acceptable leakage-rate test methods, procedures, and analyses that may be used to implement these requirements and criteria are provided in Regulatory Guide 1.163, Performance-Based Containment Leak-Test Program.
Option B in 10 CFR Part 50, Appendix J, Section III, Performance-Based Leakage-Test Requirements, states in part the following:
B. Type B and C Tests Type B pneumatic tests to detect and measure local leakage rates across pressure retaining, leakage-limiting boundaries, and Type C pneumatic tests to measure containment isolation valve leakage rates, must be conducted (1) prior to initial criticality, and (2) periodically thereafter at intervals based on the safety significance and historical performance of each boundary and isolation valve to ensure the integrity of the overall containment system as a barrier to fission product release to reduce the risk from reactor accidents. The performance-based testing program must contain a performance criterion for Type B and C tests, consideration of leakage-rate limits and factors that are indicative of or affect performance, when establishing test intervals, evaluations of performance of containment system components, and comparison to previous test results to examine the performance history of the overall containment system to limit leakage. The tests must demonstrate that the sum of the leakage rates at accident pressure of Type B tests, and pathway leakage rates from Type C tests, is less than the performance criterion (La) with margin, as specified in the Technical Specification.
3.0 TECHNICAL EVALUATION
In alternative request HNP-IST-004-RR1, the licensee requested to implement an alternative to certain IST requirements of the 2004 Edition through 2006 Addenda of the ASME OM Code to extend the leak testing interval for specific Target Rock solenoid-operated valves for the remainder of the Fourth 10-Year IST Program interval at HNP.
The NRC staff has reviewed the information provided by the licensee in support of alternative request HNP-IST-004-RR1, and the results of the NRC staff review are described below.
3.1 ASME Code Components Affected by the Proposed Alternative The licensee stated the proposed alternative are for testing for the following active safety-related Target Rock solenoid valves at Harris:
Valve ID Function Safety Position 1SP-12 Hydrogen Analyzer Cabinet "1A" Supply Iso Vlv (CIV)
CLOSED 1SP-16 REM-3502A Inlet from Containment Atmosphere Iso Vlv (CIV)
CLOSED 1SP-40 Pressurizer Liquid Space Sample Iso Vlv (CIV)
CLOSED 1SP-41 Pressurizer Liquid Space Sample Iso Vlv (CIV)
CLOSED Valve ID Function Safety Position 1SP-42 Hydrogen Analyzer Cabinet "1B" Supply Iso Vlv (CIV)
CLOSED 1SP-59 Pressurizer Steam Space Sample Iso Vlv (CIV)
CLOSED 1SP-60 Pressurizer Steam Space Sample Iso Vlv (CIV)
CLOSED 1SP-62 Hydrogen Analyzer Cabinet "1B" Return Iso Vlv (CIV)
CLOSED 1SP-78 SIS Accumulator "A" Sample Iso Vlv (CIV)
CLOSED 1SP-81 SIS Accumulator "B" Sample Iso Vlv (CIV)
CLOSED 1SP-84 SIS Accumulator "C" Sample Iso Vlv (CIV)
CLOSED 1SP-85 SIS Accumulator Sample Iso Vlv (CIV)
CLOSED 1SP-200 PASS Liquid Return Header Iso Vlv (CIV)
CLOSED 1SP-201 PASS Liquid Return Header Iso Vlv (CIV)
CLOSED 1SP-208 PASS Gas Return Header Iso Vlv (CIV)
CLOSED 1SP-209 PASS Gas Return Header Iso Vlv (CIV)
CLOSED 1SP-915 Hydrogen Analyzer Cabinet "1A" Return Iso Vlv (CIV)
CLOSED 1SP-916 REM-3502A Inlet from Containment Atmosphere Iso Vlv (CIV)
CLOSED 1SP-917 Hydrogen Analyzer Cabinet "1A" Return Iso Vlv (CIV)
CLOSED 1SP-918 REM-3502A Sample Return to Containment Atmosphere Iso Vlv (CIV)
CLOSED 1SP-919 Hydrogen Analyzer Cabinet "1B" Return Iso Vlv (CIV)
CLOSED 1SP-939 REM-3502A Sample Return to Containment Atmosphere Iso Vlv (CIV)
CLOSED 1SP-941 Hydrogen Analyzer Cabinet "1A" Return Iso Vlv (CIV)
CLOSED 1SP-943 Hydrogen Analyzer Cabinet "1B" Return Iso Vlv (CIV)
CLOSED 1SP-948 RCS Sample Line Iso Vlv (CIV)
CLOSED 1SP-049 RCS Sample Line Iso Vlv (CIV)
CLOSED Legend: Iso Vlv (CIV) - Isolation Valve (Containment Isolation Valve)
REM - Radioactive Effluent Monitor SIS - Safety Injection System PASS - Post Accident Sampling System 3.2 Applicable Code Edition, Addenda, and Requirements The Fourth 10-Year IST Program interval began on May 2, 2017, and is scheduled to end on April 30, 2027. The applicable OM Code of Record for the Fourth 10-Year IST Program interval at Harris is the 2004 Edition through 2006 Addenda of the ASME OM Code as incorporated by reference in 10 CFR 50.55a.
The IST requirements in the 2004 Edition through the 2006 Addenda of the ASME OM Code, Subsection ISTC, Inservice Testing of Valves in Light-Water Reactor Nuclear Power Plants, paragraph ISTC-3700, Position Verification Testing, as incorporated by reference in 10 CFR 50.55a, related to this alternative request are as follows:
Valves with remote position indicators shall be observed locally at least once every 2 years to verify that valve operation is accurately indicated. Where practicable, this local observation should be supplemented by other indications such as use of flow meters or other suitable instrumentation to verify obturator position. These observations need not be concurrent. Where local observation is not possible, other indications shall be used for verification of valve operation.
3.3
Reason for Request
The licensee indicated that Harris has utilized Local Leak Rate Test (LLRT) procedures, which are performed on an Option A schedule (every refueling outage) under 10 CFR Part 50, Appendix J, for verifying that the remote position indication for the tabulated valves is accurate, as local observation of solenoid movement is prohibited by valve design. According to the licensee, HNP recently implemented Amendment No. 181 (ML20259A512) to renewed Facility Operating License No. NPF-63 to adopt Option B of 10 CFR Part 50, Appendix J, consistent with Nuclear Energy Institute (NEI) 94-01, Revision 3-A, Industry Guideline for Implementing Performance-Based Option of 10 CFR Part 50, Appendix J. Under Option B, and its performance-based Type C test intervals, a Type C valve may have its LLRT interval extended up to 75 months upon completion of two consecutive periodic as-found Type C tests where the result of each test is within a licensee's allowable administrative limits. The licensee stated that ASME OM Code, Subsection ISTC, paragraph ISTC-3700, requires the verification of valve operation every 2 years, which conflicts with the allowable Option B performance-based interval for valves eligible for an extended Type C test interval.
The licensee proposes an alternative to the provisions of paragraph ISTC-3700 to allow utilization of the 10 CFR Part 50, Appendix J, Option B LLRT schedule for conducting the ISTC-3700 position verification tests for the specified solenoid-operated valves that qualify for testing on a frequency eligible under Option B.
3.4 Licensees Proposed Alternative and Basis for Use The licensee described its proposed alternative and the basis for its use as follows:
In accordance with ISTC-3700, where local observation is not possible, other indications shall be used to verify valve position. Shearon Harris performs and utilizes procedure EST-212, Type C Local Leak Rate Tests, to confirm closed indication when pressurizing these solenoid valves to a differential pressure of greater than or equal to the calculated peak containment internal pressure related to the design basis loss-of-coolant accident (Pa, 41.8 psig [pounds per square inch gage]) during local leak rate testing. Open indication is confirmed for these solenoid valves by verification of an increase in makeup flow when the valve is taken to the open position. This method satisfies the requirement for position indication verification and ensures that the indicating lights correspond to valve position.
The subject valves are designed such that the position of the valve is not locally observable.
The Shearon Harris Inservice Testing Program ISTC-3700 requirements for these valves are performed in conjunction with local leak rate testing as described above due to solenoid valve design. Shearon Harris has recently implemented Amendment No. 181 to adopt Option B of 10 CFR [Part] 50, Appendix J consistent with NEI 94-01, Revision 3-A.
Under Option B, and its performance-based Type C test intervals, a Type C valve may have its LLRT interval extended up to 75 months upon completion of two consecutive periodic as-found Type C tests where the results of each test are within a licensee's allowable administrative limits.
For the subject solenoid valves, as an alternative to the ISTC-3700 2-year frequency requirement, Shearon Harris requests relief from the ISTC-3700 frequency requirements and proposes to perform the alternate method where local leak rate equipment is used to confirm indication is accurate for these solenoid valves where local observation is not possible on the Option B schedule of NEI 94-01, Revision 3-A. The qualification of a valve for an extended Type C test interval under 10 CFR [Part] 50, Appendix J Option B, based on successful LLRT, is one general indicator of the structure, system, or components (SSCs) operational readiness.
The operational readiness of these SSCs [structures, systems, and components] is also monitored during quarterly inservice testing. Shearon Harris procedure OST-1038, Sampling, Chemical Addition, and Main Steam Drain Systems ISI [Inservice Inspection]
Valve Test Quarterly Mode 1 - 4 or OST-1062 Sampling, Chemical Addition, and Main Steam Drain Systems ISI Valve Test and Remote Position Indication Test 2 Year Interval Modes 1, 2, 3 and 4 performs a quarterly fail safe (closed) test of the valves in conjunction with stroke time testing to the closed (safety) position of the valve. The quarterly measurement of stroke time and its comparison to the applicable criteria of ISTC-5152, Stroke Test Acceptance Criteria, provides another general indicator of the SSCs operational readiness in addition to the testing performed under 10 CFR [Part] 50, Appendix J.
In conclusion, the ability to detect degradation of these SSCs and ensure their operational readiness is performed quarterly during fail safe and stroke time (closed) testing during OST-1038 or OST-1062. A further assessment of the components operational readiness is assessed during Type C testing on an Option B (NEI 94-01, Revision 3-A) schedule, with valves exhibiting acceptable local leakage-rate testing performance eligible for testing on an extended test interval of up to 75 months. Performance of the ISTC-3700 indicator check on an Option B schedule provides an acceptable level of quality and safety, for those qualifying for local leakage-rate testing on said schedule, in conjunction with quarterly fail safe and stroke time testing.
3.5 Duration of Proposed Alternative The licensee requested NRC authorization of the alterative HNP-IST-004-RR1 for the remainder of the Fourth 10-Year IST Program interval, which began on May 2, 2017, and is scheduled to end on April 30, 2027.
3.6
NRC Staff Evaluation
In Alternative Request HNP-IST-004-RR1, the HNP licensee proposes an alternative in accordance with 10 CFR 50.55a(z)(1) to certain IST requirements in the 2004 Edition through the 2006 Addenda of the ASME OM Code, Subsection ISTC, paragraph ISTC-3700, to allow use of the 10 CFR Part 50, Appendix J, Option B LLRT schedule for conducting the required ISTC-3700 position verification tests for the valves listed in Table 1 of this SE. Under Option B of 10 CFR Part 50, Appendix J, and its performance-based Type C test intervals, a Type C valve may have its LLRT interval extended up to 75 months upon completion of two consecutive periodic as-found Type C tests where the results of each test are within a licensee's allowable administrative limits. As discussed below, the NRC staff reviewed the information provided by the licensee in support of its proposed position verification testing for the valves at HNP within the scope of Alternative Request HNP-IST-004-RR1 for compliance with the requirements of 10 CFR 50.55a(z)(1).
On December 8, 2020 (ML20259A512), the NRC issued an amendment to the operating license for HNP to revise Technical Specification 6.8.4.k, Containment Leakage Rate Testing Program, by replacing the reference to Regulatory Guide 1.163, Performance-Based Containment Leak-Test Program, with a reference to NEI 94-01, Revision 3-A, and the conditions and limitations specified in NEI 94-01, Revision 2-A, dated October 2008. Provided the specified conditions and limitations are satisfied, the HNP license amendment will allow a permanent extension of the Type A test interval from 10 years to 15 years, a more conservative allowable test interval extension of 9 months for Type A, Type B, and Type C leakage-rate tests, and an extension of the Type C test interval up to 75 months.
Guidance for implementation of acceptable leakage-rate test methods, procedures, and analyses is provided in RG 1.163, which endorses NEI Topical Report 94-01, Revision 0, dated July 26, 1995, with the limitation that the Type C components test intervals cannot extend greater than 60 months. Revision 3-A to NEI 94-01 allows the Type C containment isolation valve test intervals to be extended to 75 months with a permissible extension for non-routine emergent conditions of 9 months (84 months total). In an SE dated June 8, 2012, the NRC staff determined that the guidance in NEI 94-01, Revision 3-A, is acceptable (ML121030286 and ML12226A546) with the following conditions:
- 1. NEI TR 94-01, Revision 3, is requesting that the allowable extended interval for Type C LLRTs be increased to 75 months, with a permissible extension (for non-routine emergent conditions) of 9 months (84 months total). The staff is allowing the extended interval for Type C LLRTs be increased to 75 months with the requirement that a licensees post-outage report include the margin between the Type B and Type C leakage-rate summation and its regulatory limit. In addition, a corrective action plan shall be developed to restore the margin to an acceptable level. The staff is also allowing the non-routine emergent extension out to 84 months as applied to Type C valves at a site, with some exceptions that must be detailed in NEI 94-01, Revision 3. At no time shall an extension be allowed for Type C valves that are restricted categorically (e.g., boiling water reactor main steam isolation valves), and those valves with a history of leakage, or any valves held to either a less than maximum interval or to the base refueling cycle interval. Only nonroutine emergent conditions allow an extension to 84 months.
- 2. The basis for acceptability of extending the integrated leak rate testing (ILRT) interval out to once per 15 years was the enhanced and robust primary containment inspection program and the local leakage-rate testing of penetrations. Most of the primary containment leakage experienced has been attributed to penetration leakage and penetrations are thought to be the most likely location of most containment leakage at any time. The containment leakage condition monitoring regime involves a portion of the penetrations being tested each refueling outage, nearly all LLRTs being performed during plant outages. For the purposes of assessing and monitoring or trending overall containment leakage potential, the as-found minimum pathway leakage rates for the just tested penetrations are summed with the as-left minimum pathway leakage rates for penetrations tested during the previous 1 or 2 or even 3 refueling outages. Type C tests involve valves which, in the aggregate, will show increasing leakage potential due to normal wear and tear, some predictable and some not so predictable. Routine and appropriate maintenance may extend this increasing leakage potential. Allowing for longer intervals between LLRTs means that more leakage-rate test results from farther back in time are summed with fewer just tested penetrations and that total used to assess the current containment leakage potential. This leads to the possibility that the LLRT totals calculated understate the actual leakage potential of the penetrations.
Given the required margin included with the performance criterion and the considerable extra margin most plants consistently show with their testing, any understatement of the LLRT total using a 5-year test frequency is thought to be conservatively accounted for.
Extending the LLRT intervals beyond 5 years to a 75-month interval should be similarly conservative provided an estimate is made of the potential understatement and its acceptability determined as part of the trending specified in NEI 94-01, Revision 3, Section 12.1. When routinely scheduling any LLRT valve interval beyond 60-months and up to 75-months, the primary containment leakage-rate testing program trending or monitoring must include an estimate of the amount of understatement in the Type B & C total, and must be included in a licensees post-outage report. The report must include the reasoning and determination of the acceptability of the extension, demonstrating that the LLRT totals calculated represent the actual leakage potential of the penetrations.
On June 10, 2022, the licensee submitted a supplement to Alternative Request HNP-IST-004-RR1 to provide clarification related to the position verification testing for the valves at HNP within the scope of the alternative request. The licensee stated that LLRT procedure EST-212, Type C Local Leak Rate Tests, in addition to confirming the closed indication of the valves, also confirms open indication by verifying an increase in the makeup flow on the Leak Rate Monitor (LRM), as local observation of solenoid movement is prohibited by valve design. The licensee asserted that this method satisfies the requirement for position indication verification, and ensures that the indicating lights correspond to valve position. The licensee stated that HNP uses the LRM per the LLRT procedure to verify remote position indication requirements. With the LLRT eligible to be performed on an Option B schedule, the licensee intends that the performance of the position verification for both open and closed indication will be performed on the same Option B performance-based interval for the valves listed in the request. The NRC staff considers that the licensee has provided an acceptable description of its plans to verify both the open and close operation of the valves at HNP within the scope of Alternative Request HNP-IST-004-RR1.
The NRC regulations in 10 CFR Part 50, Appendix J, Option B, require that the individual CIVs be good performers before they can be placed on the extended seat leakage testing frequency.
In its April 7, 2022, submittal, the licensee provided the recent historical leakage performance of the valves at HNP within the scope of Alternative Request HNP-IST-004-RR1 in Attachment 1, Valve Local Leak Rate Test (LLRT) History Sample (Last Three Tests), and Attachment 2, Position Indication Test History Sample (Last Three Tests). The NRC staff reviewed the performance history provided in these attachments for the valves within the scope of Alternative Request HNP-IST-004-RR1. As indicated in the attachments to the licensees April 7, 2022, submittal, most of the valves within the scope of Alternative Request HNP-IST-004-RR1 have revealed successful leakage performance such that they currently satisfy the performance requirement of two successful most recent periodic leak tests to support extending their leak-test interval. However, a few valves (such as 1SP-16, 1SP-40, 1SP-41, 1SP-84, 1SP-85¸and 1SP-201) have not revealed successful leakage performance during the two most recent periodic leak tests. The provisions of Alternative Request HNP-IST-004-RR1 would not allow the valves identified in the request that have not demonstrated successful leakage performance during the two most recent successful periodic leak tests to have their leak-test intervals extended at this time. In the future, the leak-test interval could be extended when a valve has demonstrated successful leakage performance during its two most recent periodic leak tests. Any valve leakage-test failure would require the valve to be returned to the initial ASME OM Code leak-test interval until good performance can again be established.
Based on the information described above for the valves at HNP within the scope of the licensees Alternative Request HNP-IST-004-RR1, the NRC staff finds that the alternative request describes a performance-based approach for leak testing of these valves such that the valves that have demonstrated good performance for two consecutive cycles may have their test interval extended up to 75 months, with a permissible extension (for non-routine emergent conditions) of 9 months (84 months total). Alternative Request HNP-IST-004-RR1 does not allow the leak-test interval to be extended for those valves that have not demonstrated successful performance during the two most recent periodic leak tests. The NRC staff finds that Alternative Request HNP-IST-004-RR1 will provide an acceptable level of quality and safety that satisfies 10 CFR 50.55a(z)(1) when implemented to establish performance-based leak testing intervals for the valves within the scope of this request at HNP that have demonstrated successful leak-test performance during the two most recent periodic leak tests.
3.6.1 NRC Staff Evaluation Summary As indicated above, the NRC staff finds that the proposed alternative request HNP-IST-004-RR1 as described in the licensees submittals dated April 7, 2022, and June 10, 2022, will provide an acceptable level of quality and safety when implemented to establish performance-based leak testing intervals for the valves at Harris listed in this section 3.1 of this SE where those valves have demonstrated successful leak-test performance during the two most recent periodic leak tests.
5.0 CONCLUSION
As set forth above, NRC staff concludes that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(1). Therefore, the NRC staff authorizes the use of alternative HNP-IST-004-RR1 at Harris for the remainder of the Fourth 10-Year IST Program interval, which began on May 2, 2017, and is scheduled to end on April 30, 2027.
All other ASME BPV Code or OM Code requirements for which an alternative was not specifically requested and approved remain applicable.
Principal Contributors: K. Hsu, NRR T. Scarbrough, NRR Date: September 2, 2022
- via email OFFICE NRR/DORL/LPL2-2/PM NRR/DORL/LPL2-2/LA NRR/DEX/EMIB/BC*
NAME MMahoney RButler SBailey DATE 08/18/2022 08/16/2022 08/08/2022 OFFICE DORL/LPL2-2/BC NAME DWrona DATE 09/02/2022