L-23-036, Report of Facility Changes, Tests and Experiments
| ML23072A077 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 03/13/2023 |
| From: | Blair B Energy Harbor Nuclear Corp |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| L-23-036 | |
| Download: ML23072A077 (1) | |
Text
energy harbor Barry N. Blair Site Vice President, Beaver Valley Nuclear March 13, 2023 L-23-036 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-001
SUBJECT:
Beaver Valley Power Station, Unit No. 1 Docket No. 50-334, License No. DPR-66 Report of Facility Changes, Tests and Experiments Energy Harbor Nuclear Corp.
Beaver Valley Power Station P. 0. Box 4 Shippingport, PA 15077 724-682-5234 10 CFR 50.59(d)(2)
In accordance with 10 CFR 50.59(d)(2), Energy Harbor Nuclear Corp. hereby submits the attached Report of Facility Changes, Tests and Experiments for the Beaver Valley Power Station, Unit No. 1 (BVPS-1 ). This report reflects the implemented changes, tests and experiments that were evaluated pursuant to 10 CFR 50.59 during the period of March 1, 2021 through January 31, 2023.
There are no regulatory commitments contained in this submittal. If there are any questions or if additional information is required, please contact Mr. Phil H. Lashley, Manager - Fleet Licensing, at 330-696-7208.
Attachment:
Beaver Valley Power Station, Unit 1, Report of Facility Changes, Tests, and Experiments cc: NRC Region I Administrator NRC Resident Inspector NRC Project Manager Director BRP/DEP Site BRP/DEP Representative
Attachment L-23-036 Beaver Valley Power Station, Unit 1 Report of Changes, Tests, and Experiments Page 1 of 6
Title:
Extend the Frequency as Listed in License Requirement Manual Table 3.3.6-2 for the Calibration Interval for the Specified Seismic Monitoring Instrumentation Activity
Description:
This change will revise Unit 1 Licensing Requirements Manual (LRM) Table 3.3.6-2, seismic monitoring instrumentation surveillance requirements as follows:
- 1. The channel calibration for the triaxial force balance accelerometers (BV-XT-1 ER-105A/B/C/D) will be performed at a 2R (36-month) frequency instead of the current required R (18-month) frequency.
- 2. The channel calibration for the high dynamic range strong motion accelerograph (BV-XR-1ER-102) will be performed at a 2R (36-month) frequency instead of the current required R (18-month) frequency.
- 3. The channel operational test for the response spectrum analyzer (1 ER-RSA-1) will be performed at a 2R (36-month) frequency instead of the current required R (18-month) frequency.
Summary of Evaluation:
The triaxial force balance accelerometers, the high dynamic range strong motion accelerograph and the response spectrum analyzer are described in the BVPS-1 Updated Final Safety Analysis Report (UFSAR), Section 5.2.8.1, Seismic Measurement.
These seismic measurement instruments have no impact on plant control, on accident response, on the consequences of any accident described in the BVPS-1 UFSAR or on the analyses methodology used in the design of the plant. The only connection to the remainder of the plant is to the control room annunciator system. Annunciator A 11-59, Seismic Accelograph Operation, will annunciate from the control room seismic panel on input from the triaxial force balance accelerometers upon a seismic event that exceeds a setpoint or if there is a failure of the system. The operators response to this alarm is to observe indications and to obtain data on the Seismic Monitoring System Cabinet, 1ER-CCC-1, located in the control room. This response is unchanged due to extending the surveillance frequencies. Therefore, changing the calibration period will not have an adverse effect on any aspect of the plant as described in the BVPS-1 UFSAR.
Extending the calibration interval will slightly raise the probability that an instrument may not be accurate when called upon to function. However, a review of the calibration history shows that since the seismic instrumentation was upgraded in 2016, the
Attachment L-23-036 Page 2 of 6 instruments have been found to be within tolerance. The triaxial force balance accelerometers have not required adjustment in the past three surveillance calibrations, with one exception. The exception being that the as-found sensor response test (SRT) for Triaxial Force Balance Accelerometer, XT-1ER-105A, performed during the fall 2019 refueling outage functional test (FT) traces were satisfactory; however, the as-found SRT traces were erratic. The vendor repaired a cold solder joint on a capacitor which corrected the problem. Additionally, it was also noted in the work order that the accelerometer was mistakenly removed from its location to support the vendor calibration prior to performing the as-found SRT and FT tests. The accelerometer was reinstalled and the as-found tests were then performed. It is unknown if the SRT as-found traces would have been satisfactory if obtained prior to removing the accelerometer; however, the repair to correct the SRT traces is unrelated to any instrument drift and was simply an electrical circuit failure. Extending the surveillance frequencies has no impact on this type of failure. The high dynamic range strong motion accelerograph has not required adjustment in the past two surveillances.
A review of the channel operational tests for these instruments from March 2017 to December 2019 resulted in no issues found. Additionally, a review of the monthly channel checks for these instruments from March 2019 to July 2020 resulted in no issues found.
The Unit 1 seismic monitoring system was upgraded in 2016; therefore, this instrumentation has limited history. The seismic monitoring instrumentation at Unit 2, which consists of a Condor System and Etna Systems, is equivalent to the Condor and Etna seismic monitoring instrumentation systems at Unit 1. With the systems being equivalent, it is reasonable to conclude that the Unit 2 seismic monitoring instrumentation calibration and maintenance history represent what can be expected for the Unit 1 systems. The Unit 2 history supports extending the calibration frequency for the Unit 1 triaxial force accelerometers, the high dynamic range strong motion accelerograph, and the channel operational test for the Unit 1 response spectrum analyzer.
Unit 2 triaxial time history accelerographs BV-2ERS-ACS-1, BV-2ERS-ACS-2, and BV-2ERS-ACS-3, along with the response spectrum analyzer, are part of the Unit 2 Condor system. This instrumentation is equivalent to Unit 1 triaxial force balance accelerometers and its response spectrum analyzer.
Unit 2 triaxial time history accelerographs BV-2ERS-RRA-1, BV-2ERS-RRA-2, and BV-2ERS-RRA-3 are part of the Etna Systems. This instrumentation is equivalent to Unit 1 high dynamic range strong motion accelerograph.
Calibration data obtained from five refueling outages spanning the period from the fall 2012 refueling outage through the fall 2018 refueling outage for the Unit 2 Condor system was reviewed and no issues were identified, with the exception of two anomalies. These anomalies occurred in the fall 2018 refueling outage. During the loss of power check for the uninterrupted power supply (UPS), the battery failed to
Attachment L-23-036 Page 3 of 6 maintain power to the system. The battery was replaced, and the loss of power test was completed successfully. This was a failure of the battery and not a failure of any instrumentation or the response spectrum analyzer.
Additionally, the analog / digital (A/D) converters in the time history accelerograph recorders were found to be slightly out-of-tolerance. The as-left zero adjustment brought all values back within the required tolerance. The acceptance criteria for the offset or zero value for an accelerograph in service bounded the slight out-of-tolerance condition found on the A/D converters. This out-of-tolerance condition would have had no effect on the functionality of the system.
Calibration data obtained from six refueling outages spanning the period from the spring 2011 refueling outage through the fall 2018 refueling outage for the Unit 2 Etna system instrumentation was reviewed with no issues identified.
Six channel operational tests (COTs) were performed from January 2018 to April 2020 for the Condor system instrumentation. Eleven COTs were performed from June 2015 to April 2020 for the Etna system instrumentation. No issues were found in either system.
Monthly channel checks were performed from December 2019 to September 2020 for the Condor system instrumentation. No issues were found during the performance of the channel check, with the exception of the channel checks performed on February 17, 2020 and April 13, 2020. During the channel check on February 17, 2020, an unexplained error message, "Missing Alarm in Analysis Results," came in, but all the requirements of the channel check were met. During the channel check on April 13, 2020, an error code was received, and the FT traces and SRT traces could not be printed. Troubleshooting attributed the cause to a bad flash memory card in the triaxle time history accelerograph recorder, BV-2ERS-ACS-1. This card was replaced, which corrected the issue. The failure of the flash memory card was a random failure and has no effect on calibration drift for any seismic monitoring instrument. Monthly channel checks were performed from May 2019 to September 2020 for the Etna system instrumentation. No issues were identified during the performances of the Etna system instrumentation channel check.
Therefore, based on the surveillance history of the Unit 1 seismic monitoring instrumentation since they were upgraded in 2016 and the surveillance history of the equivalent seismic monitoring instrumentation at Unit 2, there is a high confidence that the instruments will be accurate, despite the longer calibration period.
Extending the calibration interval for the seismic monitoring listed instrumentation listed in LRM Table 3.3.6-2 does not meet any of the criteria in 10 CFR 50.59(c)(2); therefore, a license amendment is not required.
Attachment L-23-036 Page 4 of 6
Title:
Remove Licensing Requirement Surveillance 3.3.9.6 for BVPS-1 Activity
Description:
This proposed change eliminates the BVPS-1 Licensing Requirement Surveillance (LRS) 3.3.9.6, reheat stop valves (RSV) and intercept valves (IV) inspection interval requirement, from the Unit 1 Licensing Requirement Manual (LRM).
Summary of Evaluation:
The input parameter (low pressure (LP) turbine RSV and IV inspection intervals, as specified in LRS 3.3.9.6) was listed as an assumption in several of the BVPS-1 turbine missile analyses of record. The RSV and IV inspections intervals were only specified in the LRM and they were never detailed in the BVPS-1 Updated Final Safety Analysis Report (UFSAR). The turbine missile analyses (BVPS-1 calculations 8700-DMC-1458, Rev. 0, 1, and 2, dated November 8, 2002, February 14, 2003, and June 5, 2003, respectively), reflected the original installed Westinghouse LP BB-281 turbines.
A review of these calculations and their references, which include two Westinghouse Commercial Atomic Power (WCAP) evaluations (11525 and 14732), do not reveal an actual use of the RSV and IV inspection intervals. In addition, previous generic Westinghouse turbine missile reports submitted to the NRC in 1987 as documented and approved in safety evaluation report dated February 2,1987, and a more specific calculation for BVPS submitted in 1992 (Accession No. ML20097A359), do not reveal any use of the specified inspection intervals. In all cases, the RSV and IV testing (stroking) intervals are discussed as the input. The 18-month testing (stroking) interval for the RSV and IV will remain as an input to the turbine missile analysis. Furthermore, the failure of the valves that would lead to the turbine overspeed events described involve mechanisms, which include valve sticking, fluid line clogs and so on, that would be identified by the periodic testing as opposed to the inspections.
The incorporation of the reheat stop valve and intercept valve inspections into the BVPS-1 licensing bases was the result of adopting the analyses, information, and reviews supporting the BVPS-2 turbine overspeed Technical Specification (TS), Section 3.3.4 and its associated surveillances, which had no BVPS-1 equivalent. At the time of the removal of the BVPS-2 TS, Section 3.3.4 and incorporation into the Beaver Valley Power Station, Unit No. 2 (BVPS-2) LRM (Accession No. ML003729909), the testing and inspection intervals were incorporated into the BVPS-1 LRM as well. These provisions reflected the Westinghouse model BB-281 turbines in use at BVPS-1 and BVPS-2 at that time.
The Westinghouse BB-281 LP turbines were replaced at both units (in 2012 and 2013) by Siemens BB-281 13.9M2 turbines. As a result, the BVPS-1 turbine missile analysis
Attachment L-23-036 Page 5 of 6 was updated based on WACP-1605, dated March 2006, as well as Siemens report CT-27472, Revision 2, dated August 2011. These reports indicated that the major overspeed event, intermediate overspeed, for which the RSV and IV valves were considered a probable input was not a significant contributor to the overall turbine missile probability. The greater contributor, destructive overspeed, depends upon the LP turbine rotor disc (blade attachment to shaft) inspections. The RSV and IV failures are not an input to that dominating event.
Based on the analyses performed and reviews conducted, it is concluded that the RSV and IV inspection intervals listed in LRS 3.3.9.6 are not significant inputs to the turbine missile overspeed analysis.
All UFSAR described plant responses and analyses remain in effect. There are no changes to the turbine missile accident description in the BVPS-1 UFSAR, Section 14.1.12. No new accidents are introduced because the plant equipment and response remain the same.
The proposed BVPS-1 LRS 3.3.9.6, LP turbine RSV and IV inspection interval elimination does not meet any of the 10 CFR 50.59(c)(2) criteria; therefore, a license amendment is not required.
Attachment L-23-036 Page 6 of 6
Title:
Evaluate the PIPESTRESS Software for Use at BVPS-1 Activity
Description:
This activity will add the PIPESTRESS program as an alternative analytical tool. The PIPESTRESS software is capable of performing piping analysis to the American National Standards Institute (ANSI) B31.1 and American Society of Mechanical Engineers (ASME) Ill Codes and is endorsed by the NRC for use on the Westinghouse AP1000 and Advanced Power Reactor 1400 (APR1400) projects as noted in references NUREG-1793, Volume 1 (Accession No. ML043450344), and APR1400, Chapter 3 (Accession No. ML18215A242).
This activity also adds PC-PREPS to the list of computer programs used in seismic Category I piping design. During the mid-1990's migration to a personal computer (PC) environment the PC-PREPS software was developed to replace STRUDL-SW and provide additional analytical features.
This activity updates the BVPS-1 UFSAR, Section 5.2 and Appendix B, with regard to the Stone & Webster Engineering software.
Summary of Evaluation:
The PIPESTRESS software has been reviewed and found acceptable for use on the AP1000 and APR1400 projects, as noted in reference NUREG-1793, Volume 1 (Accession No. ML043450344), and APR1400, Chapter 3 (Accession No. ML18215A242). The software code was specifically approved as applied to its use on ASME Code Class 1, 2 and 3 piping.
Therefore, in accordance with 10 CFR 50.59, this change in software is not considered a change in evaluation methods that requires NRC approval.
PC-PREPS was developed from STRUDL-SW and added the ability to analyze welds, local tube steel stresses, anchor bolts, and surface mounted base plates in accordance with American Institute of Steel Construction (AISC), American Welding Society (AWS) and ASME criteria. PC-PREPS is a quality assurance (QA) Category I structural analysis computer code qualified in accordance with the Stone & Webster QA Program. PC-PREPS has been used for other Stone & Webster projects that have been reviewed and accepted by the NRC for pipe support and structural analysis. Therefore, in accordance with 10 CFR 50.59, this change in software is not considered a change in evaluation methods that requires NRC approval.
The application of PIPESTRESS or PC-PREPS software does not meet any of the 10 CFR 50.59(c)(2) criteria; therefore, a license amendment is not required.