CNL-20-093, Supplement to Application to Modify the Watts Bar Nuclear Plant Unit 1 and Unit 2 Technical Specifications 5.7.2.19 Containment Leakage Rate Testing Program (WBN-TS-19-01)
| ML20350B799 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 12/15/2020 |
| From: | Polickoski J Tennessee Valley Authority |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| CNL-20-093, EPID L-2020-LLA-0223, WBN-TS-19-01 | |
| Download: ML20350B799 (12) | |
Text
Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-20-093 December 15, 2020 10 CFR 50.90 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Units 1 and 2 Facility Operating Licenses Nos. NPF-90 and NPF-96 NRC Docket Nos. 50-390 and 50-391
Subject:
Supplement to Application to Modify the Watts Bar Nuclear Plant Unit 1 and Unit 2 Technical Specifications 5.7.2.19 Containment Leakage Rate Testing Program (WBN-TS-19-01) (EPID L-2020-LLA-0223)
Reference:
TVA letter to NRC, CNL-20-006, Application to Modify the Watts Bar Nuclear Plant Unit 1 and Unit 2 Technical Specifications 5.7.2.19 Containment Leakage Rate Testing Program (WBN-TS-19-01), dated October 2, 2020 (ML20276A092 and ML20276A093)
In the referenced letter, Tennessee Valley Authority (TVA) submitted a request for an amendment to Facility Operating License Nos. NPF-90 and NPF-96 for the Watts Bar Nuclear Plant (WBN), Units 1 and 2, respectively. The proposed change revises the WBN Units 1 and 2, Technical Specifications (TS) 5.7.2.19, "Containment Leakage Rate Testing Program," by adopting Nuclear Energy Institute (NEI) 94-01, Revision 3-A, "Industry Guideline for Implementing Performance-Based Option of 10 CFR Part 50, Appendix J," as the implementation document for the performance-based Option B of 10 CFR Part 50, Appendix J. The proposed change also extends the Type A containment integrated leak rate testing (CILRT) interval from 10 years to 15 years and the Type C local leakage rate testing intervals from 60 months to 75 months.
Section 3.8.4 of the referenced letter states TVA plans to perform a confirmatory test, as recommended in the Kalsi Engineering report, during the WBN Unit 2 Cycle 3 Refueling Outage (U2R3) which is scheduled to commence in October 2020. To assist the Nuclear Regulatory Commission (NRC) in their review of the referenced license amendment request, the results of the confirmatory test are provided in Enclosure 1 to this submittal.
U.S. Nuclear Regulatory Commission CNL-20-093 Page 2 December 15, 2020 Additionally, the title of NEI 94-01 was not properly quoted in Section 2.0 of Enclosure 1 to the referenced letter and in the proposed changes to WBN Units 1 and 2 TS 5.7.2.19 in Attachments 1, 2, 3, and 4 to Enclosure 1 to Reference 1. Therefore, Enclosure 2 to this submittal provides the corrected Section 2.0 of Enclosure 1 to the referenced letter. to this submittal provides the corrected markups to WBN Units 1 and 2 TS 5.7.2.19 and Enclosure 4 to this submittal provides the corrected final typed WBN Units 1 and 2 TS 5.7.2.19. Enclosures 2, 3, and 4 to this submittal supersede the corresponding information in the referenced letter.
This letter does not change the no significant hazard considerations nor the environmental considerations contained in Reference 1. Additionally, in accordance with 10 CFR 50.91(b)(1), TVA is sending a copy of this letter and the enclosure to the Tennessee Department of Environment and Conservation.
There are no new regulatory commitments associated with this submittal. Please address any questions regarding this request to Kimberly D. Hulvey at (423) 751-3275.
I declare under penalty of perjury that the foregoing is true and correct. Executed on this 15th day of December 2020.
Respectfully, James T. Polickoski Director, Nuclear Regulatory Affairs Enclosures
- 1. Watts Bar Nuclear Plant (WBN) Unit 2 Low Pressure Confirmatory Local Leak Rate Test (LLRT) Results
- 2. Corrected Section 2.0 of Enclosure 1 to CNL-20-006
NRC Regional Administrator - Region II NRC Senior Resident Inspector - Watts Bar Nuclear Plant NRC Project Manager - Watts Bar Nuclear Plant Director, Division of Radiological Health - Tennessee State Department of Environment and Conservation
CNL-20-093 E1-1 of 1 Watts Bar Nuclear Plant (WBN) Unit 2 Low Pressure Confirmatory Local Leak Rate Test Results Section 3.8.4 of the referenced letter states TVA plans to perform a confirmatory test, as recommended in the Kalsi Engineering report, during the WBN Unit 2 Cycle 3 Refueling Outage (U2R3) which is scheduled to commence in October 2020. The Kalsi Engineering report (Document No. 3960C, Revision 0) was included as Enclosure 3 to the referenced letter. The Kalsi Engineering report recommended confirmatory Local Leak Rate Tests (LLRT) to be performed at low pressure (less than 15 pounds per square inch gauge (psig))
on certain hard-seated check valves in order to validate their conclusion that an increase in test pressure would not decrease leakage rate through these check valves.
The existing LLRT procedures were modified to measure leakage as test pressure is increased from zero to a range of 9.36 psig to 9.5 psig and measure leakage again as test pressure is raised to the normal LLRT pressure of 15.5 psig to 16.0 psig. Results for these tests are provided below.
Valve / Valve Combination Low Test Pressure
[pounds per square inch gauge (psig)]
Low Pressure Leakage Rate
[standard cubic feet per hour (scfh)]
Normal Test Pressure (psig)
Normal Leakage Rate (scfh) 2-CVK-26-1296 9.40 0.000 15.81 0.000 2-CKV-62-639 and 2-FCV-62-61 9.37 0.017 15.75 0.031 2-CKV-81-502 9.36 0.015 15.75 0.038 The confirmatory test results demonstrate that leakage rates actually increase as pressure increases. It appears that the increase in test pressure of approximately 6.5 psig is not enough to deform the hard seats in manner that changes the profile of the leakage pathway and the result is higher pressure equals higher leakage rate.
Therefore, testing the hard-seated check valves at the higher pressure of 15.5 psig to 16.0 psig versus the calculated Pa of 9.36 psig will not decrease the component leakage rate and will not adversely affect the total containment leakage rate comparison to Technical Specification leakage rate acceptance criteria (La).
Reference TVA letter to NRC, CNL-20-006, Application to Modify the Watts Bar Nuclear Plant Unit 1 and Unit 2 Technical Specifications 5.7.2.19 Containment Leakage Rate Testing Program (WBN-TS-19-01), dated October 2, 2020 (ML20276A092 and ML20276A093)
CNL-20-093 Corrected Section 2.0 of Enclosure 1 to CNL-20-006 CNL-20-006 E1-3 of 41 1.0
SUMMARY
DESCRIPTION In accordance with the provisions of Title 10 of the Code of Federal Regulations (10 CFR) 50.90, "Application for amendment of license, construction permit, or early site permit," Tennessee Valley Authority (TVA) is requesting a license amendment to Facility Operating License Nos. NPF-90 and NPF-96 for the Watts Bar Nuclear Plant (WBN), Units 1 and 2.
This evaluation supports a request to revise WBN Units 1 and 2, Technical Specifications (TS) 5.7.2.19, "Containment Leakage Rate Testing Program," by adopting Nuclear Energy Institute (NEI) 94-01, Revision 3-A, "Industry Guideline for Implementing Performance-Based Option of 10 CFR Part 50, Appendix J,"
(Reference 1) as the implementation document for the performance-based Option B of 10 CFR Part 50, Appendix J. The proposed changes permanently extend the Type A containment integrated leak rate testing (CILRT) interval from 10 years to 15 years and the Type C local leakage rate testing (LLRT) intervals from 60 months to 75 months. In addition, a clarification of the value of Pa to be used for containment leakage rate testing purposes is incorporated.
2.0 DETAILED DESCRIPTION The following is a detailed description of the proposed TS changes for WBN Unit 1 and Unit 2.
x WBN Unit 1 TS 5.7.2.19 is revised as follows:
5.7.2.19 Containment Leakage Rate Testing Program A program shall be established to implement the leakage rate testing of the containment as required by 10 CFR 50.54(o) and 10 CFR 50 Appendix J, Option B, as modified by approved exemptions. This program shall be in accordance with the guidelines contained in Regulatory Guide (RG) 1.163, Performance-Based Containment Leak-Test Program, dated September 1995 NEI 94-01, "Industry Guideline for Implementing Performance-Based Option of 10 CFR 50, Appendix J," Revision 3-A, July 2012, and Section 4.1, "Limitations and Conditions for NEI TR 94-01, Revision 2," of the NRC Safety Evaluation Report in NEI 94-01, Revision 2-A, dated October 2008, as modified below:
The peak calculated containment internal pressure for the design basis loss of coolant accident, Pa, is 15.0 psig.
For containment leakage rate testing purposes, a value of 15.0 psig, which is equivalent to the maximum allowable internal containment pressure, is utilized for Pa to bound a range of peak calculated containment internal pressures from 9.0 to 15.0 psig for the design basis loss of coolant accident.
CNL-20-006 E1-4 of 41 x
WBN Unit 2 TS 5.7.2.19 is revised as follows:
5.7.2.19 Containment Leakage Rate Testing Program A program shall be established to implement the leakage rate testing of the containment as required by 10 CFR 50.54(o) and 10 CFR 50 Appendix J, Option B, as modified by approved exemptions. This program shall be in accordance with the guidelines contained in Regulatory Guide (RG) 1.163, Performance-Based Containment Leak-Test Program, dated September 1995.
NEI 94-01, "Industry Guideline for Implementing Performance-Based Option of 10 CFR 50, Appendix J," Revision 3-A, July 2012, and Section 4.1, "Limitations and Conditions for NEI TR 94-01, Revision 2," of the NRC Safety Evaluation Report in NEI 94-01, Revision 2-A, dated October 2008, as modified below:
For containment leakage rate testing purposes, a value of 15.0 psig, which is equivalent to the maximum allowable internal containment pressure, is utilized for Pa to bound thea range of peak calculated containment internal pressures from 9.0 to 15.0 psig for the design basis loss of coolant accident.
Note that the existing version of TS 5.7.2.19 for WBN Unit 2 already included the language regarding the use of 15.0 pounds per square inch gauge (psig) as Pa for containment leakage rate testing program purposes.
Attachments 1 and 2 to this enclosure provide the existing TS pages marked-up to show the proposed changes for WBN Unit 1 and Unit 2, respectively. Attachments 3 and 4 to this enclosure provide the WBN Unit 1 and Unit 2 TS pages retyped to show the proposed changes. Attachment 5 to this enclosure provides the existing WBN Unit 1 TS Bases pages marked-up to show the proposed changes. Only the Unit 1 TS Bases pages have been provided, as the Unit 2 changes will be nearly identical except for some editorial differences. Changes to the existing TS Bases are provided for information only and will be implemented under the TS Bases Control Program.
3.0 TECHNICAL EVALUATION
3.1 Background
The testing requirements of 10 CFR 50, Appendix J (Reference 2), provide assurance that leakage from the containment, including systems and components that penetrate the containment, does not exceed the allowable leakage values specified in TS 5.7.2.19. The periodic surveillance of containment penetrations and isolation valves ensure that proper maintenance and repairs can be performed on the systems and components penetrating containment during the service life of the containment. The limitation on containment leakage provides assurance that the containment would perform its design function following an accident up to and including the plant design basis accident. Appendix J identifies three types of required tests: (1) Type A tests, intended to measure the containment overall integrated leakage rate; (2) Type B tests, intended to detect local leaks and to measure leakage across pressure-containing or leakage limiting boundaries (other than valves) for containment penetrations; and (3) Type C tests, intended to measure containment isolation valve leakage. Type B and C tests identify the vast majority of potential containment leakage paths. Type A tests identify the overall
Corrected Markups to WBN Units 1 and 2 TS 5.7.2.19
Procedures, Programs, and Manuals 5.7 (continued)
Watts Bar-Unit 1 5.0-24 Amendment 5, 63, 135, XX 5.7 Procedures, Programs, and Manuals 5.7.2.18 Safety Function Determination Program (SFDP) (continued)
A loss of safety function exists when, assuming no concurrent single failure, a safety function assumed in the accident analysis cannot be performed. For the purpose of this program, a loss of safety function may exist when a support system is inoperable, and:
a.
A required system redundant to the system(s) supported by the inoperable support system is also inoperable; or b.
A required system redundant to the system(s) in turn supported by the inoperable supported system is also inoperable; or c.
A required system redundant to the support system(s) for the supported systems (a) and (b) above is also inoperable.
5.7.2.19 The SFDP identifies where a loss of safety function exists. If a loss of safety function is determined to exist by this program, the appropriate Conditions and Required Actions of the LCO in which the loss of safety function exists are required to be entered.
Containment Leakage Rate Testing Program A program shall be established to implement the leakage rate testing of the containment as required by 10 CFR 50.54(o) and 10 CFR 50 Appendix J, Option B, as modified by approved exemptions. This program shall be in accordance with the guidelines contained in Regulatory Guide (RG) 1.163, Performance-Based Containment Leak-Test Program, dated September 1995. NEI 94-01, "Industry Guideline for,PSOHPHQWLQJ
Performance-Based Option of 10 CFR 50, Appendix J," Revision 3-A, July 2012, and Section 4.1, "Limitations and Conditions for NEI TR 94-01, Revision 2," of the NRC Safety Evaluation Report in NEI 94-01, Revision 2-A, dated October 2008, as modified below:
The peak calculated containment internal pressure for the design basis loss of coolant accident, Pa, is 15.0 psig.
For containment leakage rate testing purposes, a value of 15.0 psig, which is equivalent to the maximum allowable internal containment pressure, is utilized for Pa to bound a range of peak calculated containment internal pressures from 9.0 to 15.0 psig for the design basis loss of coolant accident.
The maximum allowable containment leakage rate, La, at Pa, is 0.25% of the primary containment air weight per day.
Procedures, Programs, and Manuals 5.7 5.7 Procedures, Programs, and Manuals (continued)
Watts Bar - Unit 2 5.0-25 Amendment 11, 39XX 5.7.2.18 Safety Function Determination Program (SFDP) (continued)
A loss of safety function exists when, assuming no concurrent single failure, a safety function assumed in the accident analysis cannot be performed. For the purpose of this program, a loss of safety function may exist when a support system is inoperable, and:
a.
A required system redundant to the system(s) supported by the inoperable support system is also inoperable; or b.
A required system redundant to the system(s) in turn supported by the inoperable supported system is also inoperable; or c.
A required system redundant to the support system(s) for the supported systems (a) and (b) above is also inoperable.
The SFDP identifies where a loss of safety function exists. If a loss of safety function is determined to exist by this program, the appropriate Conditions and Required Actions of the LCO in which the loss of safety function exists are required to be entered.
5.7.2.19 Containment Leakage Rate Testing Program A program shall be established to implement the leakage rate testing of the containment as required by 10 CFR 50.54(o) and 10 CFR 50 Appendix J, Option B, as modified by approved exemptions. This program shall be in accordance with the guidelines contained in Regulatory Guide (RG) 1.163, Performance-Based Containment Leak-Test Program, dated September 1995. NEI 94-01, "Industry Guideline for Implementing Performance-Based Option of 10 CFR 50, Appendix J," Revision 3-A, July 2012, and Section 4.1, "Limitations and Conditions for NEI TR 94-01, Revision 2," of the NRC Safety Evaluation Report in NEI 94-01, Revision 2-A, dated October 2008, as modified below:
For containment leakage rate testing purposes, a value of 15.0 psig, which is equivalent to the maximum allowable internal containment pressure, is utilized for Pa to bound the a range of peak calculated containment internal pressures from 9.0 to 15.0 psig for the design basis loss of coolant accident.
The maximum allowable containment leakage rate, La, at Pa, is 0.25%
of the primary containment air weight per day.
Corrected Final Typed WBN Units 1 and 2 TS 5.7.2.19
Procedures, Programs, and Manuals 5.7 (continued)
Watts Bar-Unit 1 5.0-24 Amendment 5, 63, 135, XX 5.7 Procedures, Programs, and Manuals 5.7.2.18 Safety Function Determination Program (SFDP) (continued)
A loss of safety function exists when, assuming no concurrent single failure, a safety function assumed in the accident analysis cannot be performed. For the purpose of this program, a loss of safety function may exist when a support system is inoperable, and:
a.
A required system redundant to the system(s) supported by the inoperable support system is also inoperable; or b.
A required system redundant to the system(s) in turn supported by the inoperable supported system is also inoperable; or c.
A required system redundant to the support system(s) for the supported systems (a) and (b) above is also inoperable.
5.7.2.19 The SFDP identifies where a loss of safety function exists. If a loss of safety function is determined to exist by this program, the appropriate Conditions and Required Actions of the LCO in which the loss of safety function exists are required to be entered.
Containment Leakage Rate Testing Program A program shall be established to implement the leakage rate testing of the containment as required by 10 CFR 50.54(o) and 10 CFR 50 Appendix J, Option B, as modified by approved exemptions. This program shall be in accordance with the guidelines contained in NEI 94-01, "Industry Guideline for,PSOHPHQWLQJPerformance-Based Option of 10 CFR 50, Appendix J," Revision 3-A, July 2012, and Section 4.1, "Limitations and Conditions for NEI TR 94-01, Revision 2," of the NRC Safety Evaluation Report in NEI 94-01, Revision 2-A, dated October 2008, as modified below:
For containment leakage rate testing purposes, a value of 15.0 psig, which is equivalent to the maximum allowable internal containment pressure, is utilized for Pa to bound a range of peak calculated containment internal pressures from 9.0 to 15.0 psig for the design basis loss of coolant accident.
The maximum allowable containment leakage rate, La, at Pa, is 0.25% of the primary containment air weight per day.
Procedures, Programs, and Manuals 5.7 5.7 Procedures, Programs, and Manuals (continued)
Watts Bar - Unit 2 5.0-25 Amendment 11, 39XX 5.7.2.18 Safety Function Determination Program (SFDP) (continued)
A loss of safety function exists when, assuming no concurrent single failure, a safety function assumed in the accident analysis cannot be performed. For the purpose of this program, a loss of safety function may exist when a support system is inoperable, and:
a.
A required system redundant to the system(s) supported by the inoperable support system is also inoperable; or b.
A required system redundant to the system(s) in turn supported by the inoperable supported system is also inoperable; or c.
A required system redundant to the support system(s) for the supported systems (a) and (b) above is also inoperable.
The SFDP identifies where a loss of safety function exists. If a loss of safety function is determined to exist by this program, the appropriate Conditions and Required Actions of the LCO in which the loss of safety function exists are required to be entered.
5.7.2.19 Containment Leakage Rate Testing Program A program shall be established to implement the leakage rate testing of the containment as required by 10 CFR 50.54(o) and 10 CFR 50 Appendix J, Option B, as modified by approved exemptions. This program shall be in accordance with the guidelines contained in NEI 94-01, "Industry Guideline for,PSOHPHQWLQJPerformance-Based Option of 10 CFR50, Appendix J," Revision 3-A, July 2012, and Section 4.1,"Limitations and Conditions for NEI TR 94-01, Revision 2," of the NRCSafety Evaluation Report in NEI 94-01, Revision 2-A, dated October2008, as modified below:
For containment leakage rate testing purposes, a value of 15.0 psig, which is equivalent to the maximum allowable internal containment pressure, is utilized for Pa to bound a range of peak calculated containment internal pressures from 9.0 to 15.0 psig for the design basis loss of coolant accident.
The maximum allowable containment leakage rate, La, at Pa, is 0.25%
of the primary containment air weight per day.