ML20145A000
| ML20145A000 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 06/03/2020 |
| From: | James Danna NRC/NRR/DORL/LPL1 |
| To: | Penfield R Energy Harbor Nuclear Corp |
| Tobin J | |
| References | |
| EPID L-2020-LLR-0049, EPID L-2020-LLR-0051 | |
| Download: ML20145A000 (15) | |
Text
June 3, 2020 Mr. Rod Penfield Site Vice President Energy Harbor Nuclear Corp.
Beaver Valley Power Station Mail Stop A-BV-SEB1 P.O. Box 4, Route 168 Shippingport, PA 15077
SUBJECT:
BEAVER VALLEY POWER STATION, UNIT 2 - RELIEF FROM THE REQUIREMENTS OF THE ASME CODE FOR REQUESTS VRR6 AND VRR5 (EPID L-2020-LLR-0049 AND EPID L-2020-LLR-0051 [COVID-19])
Dear Mr. Penfield:
By letters dated April 1, 2020 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML20092K723 and ML20092L517), Energy Harbor Nuclear Corp.
(the licensee) proposed an alternative to certain inservice testing program requirements of the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code), 2004 Edition through 2006 Addenda, for Beaver Valley Power Station, Unit 2 (Beaver Valley 2), pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Section 55a.
Specifically, pursuant to 10 CFR 50.55a(z)(2), the licensee submitted request number VRR6 to extend the performance of IST program diagnostic testing for 15 specific motor-operated valves at Beaver Valley 2 listed in the request from refueling outage 2R21, scheduled to begin on April 12, 2020, to refueling outage 2R22, planned for the fall of 2021. In its submittal, the licensee requested use of the proposed alternative for the 15 specified motor-operated valves at Beaver Valley 2 on the basis that compliance with the MOV diagnostic testing provisions during the spring 2020 refueling outage would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety pursuant to 10 CFR 50.55a(z)(2).
Additionally, the licensee submitted request number VRR5 for authorization to extend the performance of the inservice testing program testing for seven specific relief valves at Beaver Valley 2 listed in the request from refueling outage 2R21, scheduled to begin on April 12, 2020, to refueling outage 2R22, planned for the fall of 2021. In its submittal, the licensee requested use of a proposed alternative for the seven specified relief valves at Beaver Valley 2 on the basis that compliance with the ASME OM Code relief valve testing requirements during the spring 2020 refueling outage would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety pursuant to 10 CFR 50.55a(z)(2).
On April 4, 2020, the U.S. Nuclear Regulatory Commission (NRC) provided a verbal authorization (ADAMS Accession No. ML20095J219) of request number VRR6 for the one-time extension of the diagnostic testing interval for the motor-operated valves at Beaver Valley 2 specified in the licensees submittal dated April 1, 2020. The verbal authorization documentation provides a summary of the NRC staffs evaluation for this request. The enclosed
R. Penfield safety evaluation provides the details of the NRC staffs review of request number VRR6 for relief from the required examination coverage and to use alternative requirements (if necessary) for inservice inspection of the vessel and pipe welds on the basis that complying with the specified requirements described in the licensees request referenced above would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
Similarly, on April 7, 2020, the NRC provided a verbal authorization (ADAMS Accession No. ML20098F301) of request number VRR5 for the one-time extension of the testing interval for the relief valves at Beaver Valley 2 specified in the licensees submittal dated April 1, 2020.
The verbal authorization documentation provides a summary of the NRC staffs evaluation for this proposed alternative. The enclosed safety evaluation provides the details of the NRC staffs review of request number VRR5.
The NRC staff finds that complying with the specified requirements in the ASME OM Code for testing of the specified motor-operated and relief valves at Beaver Valley 2 during the refueling outage in the spring of 2020 would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(2).
All other ASME OM Code,Section XI requirements for which relief was not specifically requested and approved remain applicable.
If you have any questions, please contact the Beaver Valley Project Manager, Jennifer Tobin, at 301-415-2328 or Jennifer.Tobin@nrc.gov.
Sincerely, Digitally signed by James James G. G. Danna Date: 2020.06.03 07:52:49 Danna -04'00' James G. Danna, Chief Plant Licensing Branch 1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-412
Enclosure:
Safety Evaluation cc: Listserv
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REGARDING RELIEF REQUESTS VRR6 AND VRR5 FOR THE TESTING OF CERTAIN VALVES ENERGY HARBOR NUCLEAR CORP.
ENERGY HARBOR NUCLEAR GENERATION LLC BEAVER VALLEY POWER STATION, UNIT 2 DOCKET NO. 50-412
1.0 INTRODUCTION
By letters dated April 1, 2020 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML20092K723 and ML20092L517), Energy Harbor Nuclear Corp.
(the licensee) proposed alternatives to certain inservice testing (IST) program requirements of the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code), 2004 Edition through 2006 Addenda, for Beaver Valley Power Station, Unit 2 (Beaver Valley 2), pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Section 55a.
Specifically, the licensee submitted 10 CFR 50.55a Request Number VRR6, Revision 0, Motor-Operated Valve Test Frequency, on April 1, 2020, requesting authorization by the U.S. Nuclear Regulatory Commission (NRC) to extend the performance of IST program diagnostic testing for 15 specific motor-operated valves (MOVs) at Beaver Valley 2 listed in the request from refueling outage 2R21, scheduled to begin on April 12, 2020, to refueling outage 2R22, planned for the fall of 2021. In its submittal, the licensee requested use of a proposed alternative for the 15 specified MOVs at Beaver Valley 2 on the basis that compliance with the MOV diagnostic testing provisions during the spring 2020 refueling outage would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety pursuant to 10 CFR 50.55a(z)(2).
The licensee also submitted 10 CFR 50.55a Request Number VRR5, Revision 0, Relief Valve Test Frequency, on April 1, 2020, requesting authorization by the NRC to extend the performance of the IST program testing for seven specific relief valves at Beaver Valley 2 listed in the request from refueling outage 2R21, scheduled to begin on April 12, 2020, to refueling outage 2R22, planned for the fall of 2021. In its submittal, the licensee requested use of a proposed alternative for the seven specified relief valves at Beaver Valley 2 on the basis that compliance with the ASME OM Code relief valve testing requirements during the spring 2020 Enclosure
refueling outage would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety pursuant to 10 CFR 50.55a(z)(2).
2.0 REGULATORY EVALUATION
The NRC regulations in 10 CFR 50.55a(f)(4), Inservice testing standards requirement for operating plants, state, in part, 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 NRC regulations in 10 CFR 50.55a(z) state, in part, that alternatives to the requirements of 10 CFR 50.55a(f) may be used when authorized by the NRC if the licensee demonstrates (1) the proposed alternatives would provide an acceptable level of quality and safety, 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.
The applicable ASME OM Code of record for the IST program at Beaver Valley 2 for the fourth 10-year IST program interval, which began on September 20, 2017, and is currently scheduled to end on September 19, 2027, is the 2004 Edition through 2006 Addenda (OMb-2006) of the ASME OM Code, as incorporated by reference in 10 CFR 50.55a.
Based on the above, and subject to the following technical evaluation, the NRC staff finds that regulatory authority exists for the licensee to request and the NRC to grant the relief requested by the licensee.
3.0 TECHNICAL EVALUATION
3.1 Background - Licensees Alternative Request VRR6 The IST requirements of the ASME OM Code, as incorporated by reference in 10 CFR 50.55a, related to this alternative request are as follows:
ASME Code Case OMN-1 (ASME OMb Code-2006), Alternative Rules for Preservice and Inservice Testing of Active Electric Motor-Operated Valve Assemblies in Light-Water Reactor Power Plants, paragraph 3.3.1, Inservice Test Interval, subparagraph (c) states, in part, that The maximum inservice test interval shall not exceed 10 years.
In its submittal, the licensee requests an extension of the diagnostic test interval for the following 15 active safety-related MOVs at Beaver Valley 2:
Table 1 Valve ID Function Code OM Class Category 2CHS*MOV308A Reactor coolant pump (RCP) 21A seal water 2 A injection isolation 2CHS*MOV308B RCP 21B seal water injection isolation 2 A 2CHS*MOV308C RCP 21C seal water injection isolation 2 A
2CHS*MOV378 RCP seal water return isolation 2 A 2CHS*MOV8130A Charging pump suction isolation 2 B 2CHS*MOV8130B Charging pump suction isolation 2 B 2SIS*MOV840 High head to cold leg injection isolation 2 A 2SIS*MOV841 High head to cold leg injection isolation 2 B 2SIS*MOV8890A Low head safety injection pump 21A mini flow 2 A recirculation isolation 2QSS*MOV101B Quench spray pump 21B discharge isolation 2 A 2CCP*MOV112B RHR heat exchanger (B train) supply isolation 3 B 2CCP*MOV150-1 Primary component cooling header isolation 2 A outside containment 2CCP*MOV151-1 Primary component cooling header isolation 2 A outside containment 2SWS*MOV155-2 Containment air recirculation cooling coils supply 2 A header isolation 2SWS*MOV113D Emergency diesel generator heat exchanger 21B 3 B service water header B cooling water inlet
Reason for Request
In its submittal, the licensee indicated that Beaver Valley 2 was scheduled to begin its next refueling outage (2R21) on April 12, 2020. The licensee reported that the 15 MOVs listed in its request are tested in accordance with ASME Code Case OMN-1 and are near the end of their 10-year test interval as specified in paragraph 3.3.1(c) of the Code case. Therefore, these MOVs were scheduled to be tested during the refueling outage in the spring of 2020.
On March 13, 2020, the President of the United States declared a national emergency due to the spread and infectious nature of the Coronavirus Disease 2019 (COVID-19) and resulting pandemic. The licensee stated that the most recent guidance at that time from the Centers for Disease Control and Prevention included recommendations for social distancing by maintaining approximately 6 feet from other personnel to limit the spread of the virus. On March 28, 2020, the Governor of Pennsylvania issued a Stay at Home order for Beaver County and the surrounding counties of Allegheny and Butler. On March 28, 2020, the Department of Homeland Security identified workers in the nuclear energy sector as essential, critical infrastructure workers.
The licensee stated that the performance of diagnostic testing of the MOVs listed in the request during the spring 2020 refueling outage at Beaver Valley 2 would represent a hardship during the COVID-19 outbreak. For example, the licensee intended to reduce the amount of personnel on site to prevent the spread of COVID-19 at Beaver Valley. The licensee was also contingency planning in case some of its workforce became unavailable due to the COVID-19 outbreak.
Therefore, the licensee asserted that the performance of diagnostic testing of the specified MOVs at Beaver Valley 2 during the spring 2020 refueling outage would result in a hardship without a compensating increase in the level of quality and safety in accordance with 10 CFR 50.55a(z)(2).
Proposed Alternative The licensee proposed a one-time extension of the IST program test intervals for the MOVs listed in Table 1 of this safety evaluation (SE) to the next refueling outage (2R22) for Beaver Valley 2, currently scheduled for the fall of 2021.
The licensee indicated that the test extension interval represented an additional 1.5 months from when the MOVs would need to be tested per ASME OM Code requirements. The MOVs listed in Table 1 of this request were last tested during refueling outage 2R15 in March 2011 and have a 10-year test frequency per ASME Code Case OMN-1, Alternative Rules for Preservice and Inservice Testing of Active Electric Motor Operated Valve Assemblies in Light-Water Reactor Power Plants. Although ASME Code Case OMN-20, Inservice Test Frequency, permits a grace period of up to 6 months, the licensee reported that it is insufficient to extend the interval to refueling outage 2R22 planned during the fall of 2021.
The licensee stated that the MOVs within the scope of its request are rising stem valves that will have their valve stems cleaned and lubricated in refueling outage 2R21, except for butterfly valves 2CCP*MOV112B, 2CCP*MOV150-1, 2CCP*MOV151-1, and 2SWS*MOV155-2 (which are not rising stem valves).
The licensee asserted that the following would ensure that the proposed alternative to test the specified MOVs during refueling outage 2R22 in the fall of 2021 provides reasonable assurance that they remain operationally ready:
The short 1.5-month test extension from the requirements in ASME Code Cases OMN-1 and OMN-20.
The MOV actuator output margin to operating requirements from the most recent tests.
The MOVs are exercised at least each refueling outage or 18 months.
Except for four butterfly valves, the others are rising stem valves that will have stem lubrication maintenance during refueling outage 2R21.
NRC Staff Evaluation
With respect to MOVs, the NRC regulations in 10 CFR 50.55a(b)(3) require nuclear power plant licensees to comply with the provisions of the ASME OM Code incorporated by reference in 10 CFR 50.55a, and to establish a program to ensure that MOVs continue to be capable of performing their design-basis safety function. The ASME OM Code establishes the requirements for preservice and inservice testing and examination of certain components to assess their operational readiness in light-water reactor nuclear power plants. For example, these requirements apply to valves that are required to perform a specific function in shutting down a reactor to the safe shutdown condition, in maintaining the safe shutdown condition, or in mitigating the consequences of an accident.
In the 2004 Edition through 2006 Addenda, the ASME OM Code testing for MOVs consisted of the following:
Valve exercising to include quarterly stroke time testing Valve obturator movement verification during the exercise test Valve leakage testing (only if the valve has a leakage limit requirement)
Remote position indication verification
In the past, these required tests were the best methods available to assess operational readiness of safety-related MOVs. However, over the course of many years of testing and operating experience, it was determined that quarterly stroke-time testing could not identify degradation in the capability of MOVs to perform their safety functions. As an alternative to MOV stroke-time testing, ASME developed Code Case OMN-1, which specifies periodic exercising and diagnostic testing for assessing the operational readiness of active MOVs as an alternative to quarterly stroke-time testing of MOVs. ASME provided additional guidance in Code Case OMN-11, Risk-Informed Testing for Motor-Operated Valves, to supplement Code Case OMN-1. ASME merged these two Code cases in the 2006 Addenda of the ASME OM Code as a revised version of Code Case OMN-1. The NRC staff has accepted Code Case OMN-1 (2006 Addenda) with certain conditions as noted in NRC Regulatory Guide (RG) 1.192, Operation and Maintenance Code Case Acceptability, ASME OM Code.
The MOVs listed in Table 1 of this SE are currently being tested in accordance with the provisions of ASME Code Case OMN-1 (2006 Addenda) and were due to be diagnostically tested during the spring 2020 refueling outage. Due to current circumstances of the nation being in a pandemic situation, the licensee requested that a one-time extension of 1.5 months be allowed for the diagnostic testing of these MOVs to the refueling outage in the fall of 2021.
The licensee considered that justification for the extension of the diagnostic testing for the specific MOVs is the excellent performance history of each MOV, and the determination that all MOVs listed in Table 1 of this SE have adequate margin to perform their safety function.
In its submittal, the licensee stated that the performance of diagnostic testing of the 15 specified MOVs during the spring 2020 refueling outage at Beaver Valley 2 would represent a hardship during the COVID-19 outbreak, because the licensee intended to reduce the amount of personnel on site to prevent the spread of COVID-19 at Beaver Valley. The licensee was also contingency planning in case some of its workforce became unavailable due to the COVID-19 outbreak.
To support its request to extend the diagnostic testing of the MOVs until the next refueling outage in the fall of 2021, the licensee provided the functional margin between valve operating requirements and the available actuator output capability to satisfy the acceptance criteria for operational readiness for each specific MOV, along with the probabilistic risk assessment ranking and exercise testing frequency. The licensee provided information indicating that each of the specified MOVs has a functional margin of at least 10 percent, based on the test data obtained during refueling outage 2R15 in March 2011. The licensee also stated that all of the specified MOVs (except for the four butterfly valves) will have their valve stems cleaned and lubricated during refueling outage 2R21.
The licensee noted that the grace period allowed in ASME Code Case OMN-20, which is accepted in Regulatory Guide 1.192, as incorporated by reference in 10 CFR 50.55a, is insufficient to extend the diagnostic test interval for these MOVs until refueling outage 2R22.
The licensee considered that the MOVs will remain operationally ready based on (1) the short 1.5-month diagnostic test interval extension from the ASME Code Cases OMN-1 and OMN-20 test schedules, (2) the available MOV functional margin, (3) exercising of these MOVs at least each refueling outage or 18 months, and (4) the planned valve stem lubrication maintenance.
In response to the licensees request, the NRC staff reviewed the historical performance data of the MOVs listed in Table 1 of this SE and performed a review of MOV operating experience for the last 20 years at Beaver Valley 2 using the Industry Reporting Information System (IRIS) database established by the Institute of Nuclear Power Operations. The staff did not identify
any significant MOV malfunctions in IRIS and only minor events that were identified during normal work activities. The NRC staff considered that the MOVs listed in Table 1 of this SE have sufficient margin and excellent performance history to justify a minor extension of 1.5 months to perform the required diagnostic testing. The staff determined that requiring the MOVs listed in Table 1 of this SE to be tested within the specified 10-year interval with limited personnel resources represents a hardship or unusual difficulty without a compensating increase in the level of quality and safety.
Based on the information provided by the licensee for the 15 specific MOVs at Beaver Valley 2 identified in the licensees submittal, the NRC staff found that (1) previous diagnostic testing of those MOVs indicates their acceptable historical performance, (2) ongoing IST activities have not identified MOV performance concerns, (3) periodic maintenance activities will continue, and (4) a hardship exists for the performance of team-oriented diagnostic testing of these MOVs during the spring 2020 refueling outage that would be contrary to the health and safety of plant personnel. Therefore, the staff determined that the licensees proposed alternative for a one-time extension of the diagnostic testing interval to the next refueling outage in the fall of 2021 for the specified 15 MOVs at Beaver Valley 2 is acceptable in accordance with 10 CFR 50.55a(z)(2). The proposed alternative will provide reasonable assurance that these MOVs will be operationally ready to perform their safety functions until the next refueling outage currently scheduled for the fall of 2021.
3.2 Licensees Alternative Request VRR5 The IST requirements of the ASME OM Code, as incorporated by reference in 10 CFR 50.55a, related to this alternative request are as follows:
ASME OM Code (2004 Edition through 2006 Addenda), Mandatory Appendix I, Inservice Testing of Pressure Relief Devices in Light-Water Reactor Nuclear Power Plants, paragraph I-1350, Test Frequency, Classes 2 and 3 Pressure Relief Valves, subparagraph (a),
10-year Test Interval, states:
Class 2 and 3 pressure relief valves, with the exception of pressurized-water reactor main steam safety valves, shall be tested every 10 years, starting with initial electric power generation. No maximum limit is specified for the number of valves to be tested during any single plant operating cycle; however, a minimum of 20 percent of the valves from each valve group shall be tested within any 48-month interval. This 20 percent shall consist of valves that have not been tested during the current 10-year test interval, if they exist. The test interval for any individual valve shall not exceed 10 years. Pressurized-water reactor main steam safety valves shall be tested in accordance with I-1320.
ASME OM Code, Mandatory Appendix I, paragraph I-1390, Test Frequency, Classes 2 and 3 Pressure Relief Devices That Are Used for Thermal Relief Application, states:
Tests shall be performed on all Classes 2 and 3 relief devices used in thermal relief application every 10 years, unless performance data indicate more frequent testing is necessary. In lieu of tests the Owner may replace the relief devices at a frequency of every 10 years, unless performance data indicate more frequent replacements are necessary.
In its submittal, the licensee requests an extension of the test interval for the following seven relief valves at Beaver Valley 2:
Table 2 Valve ID Function Code OM Class Category 2RHS*RV721B Residual heat removal system (RHS) Train B 2 C Supply Relief 2CHS*RV160 Chemical and volume control system (CHS) Loop 2 C Fill Header Relief 2SIS*RV175 Safety injection system (SIS) Relief on Back 2 A/C Leakage Line Outside Rx CNMT 2RSS*RV156B Recirculation Spray Pump (RSS) 21B Discharge 2 C Valve Relief 2CCP*RV109 Component cooling water system (CCP) Seal 3 C Water Heat Exchanger Relief 2CCP*RV119B Component cooling water RHS Heat Exchanger 3 C Cooling Water Return Relief 2CCP*RV139E Component cooling water Containment 3 C Penetration Cooling Coil No.40 Relief
Reason for Request
In its submittal, the licensee indicated that Beaver Valley 2 was scheduled to begin its next refueling outage (2R21) on April 12, 2020. The licensee reported that the seven relief valves listed in its request were at the end of their test intervals, as specified by the ASME OM Code, Appendix I, paragraphs I-1350(a) and I-1390, and were scheduled to be tested during the refueling outage in the spring of 2020.
On March 13, 2020, the President of the United States declared a national emergency due to the spread and infectious nature of the Coronavirus Disease 2019 (COVID-19) and resulting pandemic. The licensee stated that the most recent guidance at that time from the Centers for Disease Control and Prevention included recommendations for social distancing by maintaining approximately 6 feet from other personnel to limit the spread of the virus. On March 28, 2020, the Governor of Pennsylvania issued a Stay at Home order for Beaver County and the surrounding counties of Allegheny and Butler. On March 28, 2020, the Department of Homeland Security identified workers in the nuclear energy sector as essential critical infrastructure workers.
The licensee stated that the performance of testing of the relief valves listed in the request during the spring 2020 refueling outage at Beaver Valley 2 would represent a hardship during the COVID-19 outbreak. For example, the licensee intended to reduce the amount of personnel on site to prevent the spread of COVID-19 at Beaver Valley. The licensee was also contingency planning in case some of its workforce became unavailable due to the COVID-19 outbreak.
Therefore, the licensee asserted that the performance of testing of the specified relief valves at Beaver Valley 2 during the spring 2020 refueling outage would result in a hardship without a compensating increase in the level of quality and safety in accordance with 10 CFR 50.55a(z)(2).
Proposed Alternative The licensee proposed a one-time extension of the IST program test intervals for the relief valves listed in Table 2 of this SE to the next refueling outage (2R22) for Beaver Valley 2, currently schedule for the fall of 2021.
The licensee provided the following information in support of its request:
RHS Train B Supply Relief Valve 2RHS*RV721B was last tested on February 17, 2011. There are two other valves in this grouping with the latest valve tested on November 13, 2018. This valve is required to be tested every 10 years, and one of three valves in the group must also be tested every 48 months to meet the 20 percent requirement. Based on the above, the date for testing this relief valve would be February 17, 2021. To extend the interval to refueling outage 2R22, approximately 8 months of additional time will be needed. This relief valve has passed its setpoint test acceptably six times over the past 31 years, while showing good performance.
The remaining relief valves are all thermal relief valves. Each of these relief valves was last tested during refueling outage 2R15 in the spring of 2011 between February 22, 2011, and April 3, 2011. Each of these valves is required to be tested every 10 years. Based on this, the date for testing each of these relief valves would be in the spring of 2021. In order to extend each of the intervals to refueling outage 2R22, an additional 61/2 to 81/2 months of time would be needed.
Thermal relief valve 2CHS*RV160 failed its setpoint test high in 2011. The relief valve was refurbished, retested, and reinstalled on April 4, 2011. Prior to that, the relief valve had passed its setpoint test acceptably five times over the past 31 years, while showing good performance.
The next testing due date is April 4, 2021, and the relief valve needs approximately 61/2 months of grace period until refueling outage 2R22.
Thermal relief valve 2SIS*RV175 passed its setpoint test acceptably five times over the past 28 years, while showing good performance. The relief valve was last tested on March 15, 2011.
The next testing due date is March 15, 2021, and the relief valve needs approximately 7 months of grace period until refueling outage 2R22.
Thermal relief valve RSS*RV156B failed its setpoint test high in 1995 and was refurbished, retested, and reinstalled. The relief valve passed its setpoint test acceptably two additional times since then, while showing good performance. The relief valve was replaced by a new valve tested on February 24, 2011. The next testing due date is February 24, 2021, and the relief valve needs approximately 8 months of additional time until refueling outage 2R22.
Thermal relief valve 2CCP*RV109 failed its setpoint test high in 2005 and was replaced with a new relief valve. The new relief valve passed its setpoint test acceptably one additional time since then, while showing good performance. The relief valve was last tested on March 21, 2011. The next testing due date is March 21, 2021, and the relief valve needs approximately 7 months of additional time until refueling outage 2R22.
Thermal relief valve 2CCP*RV119B failed its last setpoint test high in 2011 and was replaced with a new relief valve that was tested on February 14, 2011. The next testing due date is February 14, 2021, and the relief valve needs approximately 8 months of additional time until refueling outage 2R22.
Thermal relief valve 2CCP*RV139E failed its last setpoint test high in 2011 and was replaced with a new relief valve, which was tested on February 2, 2011. The next testing due date is February 2, 2021, and the relief valve needs approximately 8.5 months of additional time until refueling outage 2R22.
The NRC approved ASME Code Case OMN-20, Inservice Test Frequency, in the latest revision of RG 1.192. ASME Code Case OMN-20 allows up to 6 months of additional time for testing intervals greater than or equal to 2 years. However, the licensee for Beaver Valley 2 needs up to an additional 2.5 months of grace period beyond what Code Case OMN-20 provides to defer testing of these relief valves from refueling outage 2R21 to refueling outage 2R22.
Based on the above information, the licensee considered that the test results for each of the relief valves show limited time-related degradation or setpoint drift and demonstrate that it is acceptable to extend the test interval to the fall of 2021.
NRC Staff Evaluation
As incorporated by reference in 10 CFR 50.55a, ASME OM Code (2004 Edition through 2006 Addenda), Mandatory Appendix I, paragraph I-1350(a), requires, in part, that ASME Boiler and Pressure Vessel Code Class 2 and 3 pressure relief valves, with the exception of pressurized-water reactor main steam safety valves, shall be tested every 10 years, starting with initial electric power generation. ASME OM Code (2004 Edition through 2006 Addenda),
Mandatory Appendix I, paragraph I-1390, requires, in part, that tests shall be performed on all ASME Boiler and Pressure Vessel Code Class 2 and 3 relief devices used in thermal relief applications every 10 years, unless performance data indicate more frequent testing is necessary.
In lieu of performing the ASME OM Code testing requirements, the licensee requested that a one-time extension to the next refueling outage currently scheduled for the fall of 2021 be allowed for the testing of the specific relief valves with the licensees justification as follows:
Table 3 Valve Last Test Next Test Extension Licensee Justification Date Date + Needed Grace (months)
Period 2RHS*RV721B 2/17/2011 8/17/2021 2 Excellent performer over the last 31 years, passing six tests.
2CHS*RV160 4/4/2011 10/4/2021 <1 Valve refurbished. Prior to refurbishment, good performer with five tests over 31 years.
2SIS*RV175 3/15/2011 9/15/2021 1 Good performer passing five tests over 28 years.
2RSS*RV156B 2/24/2011 8/24/2021 11/2 Valve failed test and refurbished in 1995, then passed two tests prior to being updated with new valve.
2CCP*RV109 3/21/2011 9/21/2021 1 Failed setpoint high at last test and updated to new valve.
2CCP*RV119B 2/24/2011 8/24/2021 11/2 Failed setpoint high at last test and updated to new valve.
2CCP*RV139E 2/2/2011 8/2/2021 21/2 Failed setpoint high last test and updated to new valve.
In its submittal, the licensee stated that testing of the seven specified relief valves during the spring 2020 refueling outage at Beaver Valley 2 would represent a hardship during the COVID-19 outbreak, because the licensee intended to reduce the amount of personnel on site to prevent the spread of COVID-19 at Beaver Valley 2. The licensee was also contingency planning in case some of its workforce became unavailable due to the COVID-19 outbreak. To support its request to extend the testing of the relief valves until the next refueling outage in the fall of 2021, the licensee provided detailed test results for the seven relief valves (one pressure relief valve and six thermal relief valves). The pressure relief valve in the residual heat removal system is among a group of three relief valves with the latest valve tested in November 2018.
The licensee reported that the residual heat removal relief valve listed in its submittal has shown good performance over the past 31 years. The remaining six valves are thermal relief valves with each valve tested during refueling outage 2R15 in the spring of 2011. These thermal relief valves either passed their setpoint test at that time or, if not, were refurbished and successfully retested, or were replaced with a new relief valve that was successfully tested.
The licensee noted that the 6-month grace period allowed in ASME Code Case OMN-20, which is accepted in RG 1.192, as incorporated by reference in 10 CFR 50.55a, is insufficient to extend the test interval for these relief valves until refueling outage 2R22. Therefore, the licensee requested an additional 2.5 months of grace period beyond the Code Case OMN-20 allowed grace period. The licensee considered that the test results for these relief valves show limited time-related degradation or setpoint drift and demonstrate that it is acceptable to extend the test interval for these relief valves to align with refueling outage 2R22.
In response to the licensees request, the NRC staff reviewed the historical performance data of the relief valves listed in Table 2 of this SE and performed a review of the Beaver Valley 2 relief valve operating experience using the IRIS database established by the Institute of Nuclear Power Operations. The staff identified one malfunction (2RSS*RV156B) in IRIS that occurred in 1995. This relief valve failed its high-lift setpoint but was determined to be less than the design limit of the system. The relief valve was refurbished and passed two tests prior to the relief valve being updated with a new relief valve in 2011. The staff has determined that the valves listed in Table 2 of this SE have had excellent performance history in that the relief valves have operated within limits for approximately 30 years. The staff considers that the licensee has maintained this good trend by incorporating valve refurbishment and replacement as needed.
The staff finds that the overall valve performance over time, coupled with the valve refurbishment and replacement efforts, justifies the extension of 2.5 months to perform the required setpoint test.
The staff determined that requiring the valves listed in Table 1 of this SE to be tested within the specified 10-year interval with limited personnel resources represents a hardship or unusual difficulty without a compensating increase in the level of quality and safety. Based on the information provided by the licensee for the seven specific relief valves at Beaver Valley 2 identified in the licensees submittal, the NRC staff found that previous testing of the current, refurbished, or new relief valves demonstrates that the short-time extension of the test interval for these specific relief valves is acceptable in light of the hardship to conduct team-oriented testing of these relief valves during the spring 2020 refueling outage that would be contrary to the health and safety of plant personnel. Therefore, the NRC determined that the licensees proposed alternative for a one-time extension of the testing interval for the seven specified relief valves at Beaver Valley 2 is acceptable in accordance with 10 CFR 50.55a(z)(2). The proposed alternative will provide reasonable assurance that these relief valves will be operationally ready to perform their safety functions until the next refueling outage currently scheduled for the fall of 2021.
4.0 CONCLUSION
On April 4, 2020, the NRC provided verbal authorization of the use of proposed alternative in request number VRR6 at Beaver Valley 2 until restart from the next refueling outage in the fall of 2021. As described in this SE, the NRC staff concluded that the proposed alternative will provide reasonable assurance that the MOVs at Beaver Valley 2 specified in the licensees submittal dated April 1, 2020, are operationally ready to perform their safety functions until the next refueling outage currently scheduled for the fall of 2021. As discussed above, the NRC staff finds that complying with the provisions of the ASME OM Code and its Code cases for diagnostic testing of the specified MOVs at Beaver Valley 2 during the refueling outage in the spring of 2020 would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(2).
On April 7, 2020, the NRC provided verbal authorization of the use of proposed alternative in request number VRR5 at Beaver Valley 2 until restart from the next refueling outage in the fall of 2021. As described in this SE, the NRC staff concluded that the alternative will provide reasonable assurance that the relief valves at Beaver Valley 2 specified in the licensees submittal dated April 1, 2020, are operationally ready to perform their safety functions until the next refueling outage currently scheduled for the fall of 2021. As discussed above, the NRC staff finds that complying with the specified requirements in the ASME OM Code for testing of the specified relief valves at Beaver Valley 2 during the refueling outage in the spring of 2020 would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(2).
All other ASME OM Code requirements as incorporated by reference in 10 CFR 50.55a for which relief or an alternative was not specifically requested and approved as part of these subject requests remain applicable. If the licensee identifies a performance issue with any of these MOVs, the licensee will be expected to take action to implement the requirements of its technical specifications. This authorization will remain in effect until restart from the next refueling outage for Beaver Valley 2 in the fall of 2021. The licensees testing plans for these MOVs may be adjusted as appropriate by any subsequent NRC-authorized alternative requests.
Principal Contributors: M. Farnan J. Huang Date: June 3, 2020
ML20145A000 OFFICE NRR/DORL/LPL1/PM NRR/DORL/LPL1/LA NRR/DEX/EMIB/BC(A)
NAME JTobin LRonewicz TScarbrough DATE 05/27/2020 05/26/2020 05/04/2020, 05/05/2020 OFFICE NRR/DORL/LPL1/BC NRR/DORL/LPL1/PM NAME JDanna JTobin DATE 06/03/2020 06/03/2020