ML20167A148
| ML20167A148 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 08/19/2020 |
| From: | Michael Wentzel Plant Licensing Branch II |
| To: | Jim Barstow Tennessee Valley Authority |
| Wentzel M | |
| References | |
| EPID L-2019-LLA-0286 | |
| Download: ML20167A148 (17) | |
Text
August 19, 2020 Mr. James Barstow Vice President, Nuclear Regulatory Affairs and Support Services Tennessee Valley Authority 1101 Market Street, LP 4A-C Chattanooga, TN 37402-2801
SUBJECT:
WATTS BAR NUCLEAR PLANT, UNITS 1 AND 2 - ISSUANCE OF AMENDMENT NOS. 136 AND 41 REGARDING THE AUTOMATIC TRANSFER FROM A UNIT SERVICE STATION TRANSFORMER TO A COMMON STATION SERVICE TRANSFORMER (EPID L-2019-LLA-0286)
Dear Mr. Barstow:
The U.S. Nuclear Regulatory Commission (Commission) has issued the enclosed Amendment No. 136 to Facility Operating License No. NPF-90 and Amendment No. 41 to Facility Operating License No. NPF-96 for the Watts Bar Nuclear Plant, Units 1 and 2, respectively. These amendments are in response to your application dated December 17, 2019.
The amendments revise Technical Specification 3.8.1, AC [Alternating Current]
Sources-Operating, to delete Surveillance Requirement 3.8.1.22 requirement to verify the operability of the automatic transfer from a Unit Service Station Transformer to a Common Station Service Transformer A or B at the associated unit board.
A copy of our related safety evaluation is also enclosed. Notice of issuance will be included in the Commissions biweekly Federal Register notice.
Sincerely,
/RA/
Michael J. Wentzel, Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-390 and 50-391
Enclosures:
- 1. Amendment No. 136 to NPF-90
- 2. Amendment No. 41 to NPF-96
- 3. Safety Evaluation cc: Listserv
TENNESSEE VALLEY AUTHORITY DOCKET NO. 50-390 WATTS BAR NUCLEAR PLANT, UNIT 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 136 License No. NPF-90
- 1.
The U.S. Nuclear Regulatory Commission (the Commission) has found that:
A.
The application for amendment by Tennessee Valley Authority (TVA, the licensee) dated December 17, 2019, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions rules and regulations set forth in 10 CFR Chapter I; B.
The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.
There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D.
The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.
The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations and all applicable requirements have been satisfied.
- 2.
Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. NPF-90 is hereby amended to read as follows:
(2)
Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A as revised through Amendment No. 136 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this license. TVA shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3.
This license amendment is effective as of the date of its issuance and shall be implemented within 30 days.
FOR THE NUCLEAR REGULATORY COMMISSION Undine Shoop, Chief Plant Licensing Branch II-2 Division of operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Operating License and Technical Specifications Date of Issuance: August 19, 2020 Undine S.
Shoop Digitally signed by Undine S. Shoop Date: 2020.08.19 09:56:40 -04'00'
ATTACHMENT TO AMENDMENT NO. 136 WATTS BAR NUCLEAR PLANT, UNIT 1 FACILITY OPERATING LICENSE NO. NPF-90 DOCKET NO. 50-390 Replace page 3 of Facility Operating License No. NPF-90 with the attached revised page 3.
Replace the following page of the Appendix A Technical Specifications with the attached page.
The revised page is identified by amendment number and contain vertical lines indicating the area of change.
Remove Page Insert Page 3.8-16 3.8-16 Unit 1 Facility License No. NPF-90 Amendment No. 136 (4)
TVA, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use in amounts as required, any byproduct, source or special nuclear material without restriction to chemical or physical form, for sample analysis, instrument calibration, or other activity associated with radioactive apparatus or components; and (5)
TVA, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.
C.
This license shall be deemed to contain and is subject to the conditions specified in the Commissions regulations set forth in 10 CFR Chapter I and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect, and is subject to the additional conditions specified or incorporated below.
(1)
Maximum Power Level TVA is authorized to operate the facility at reactor core power levels not in excess of 3459 megawatts thermal.
(2)
Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A as revised through Amendment No. 136 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this license. TVA shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
(3)
Safety Parameter Display System (SPDS) (Section 18.2 of SER Supplements 5 and 15)
Prior to startup following the first refueling outage, TVA shall accomplish the necessary activities, provide acceptable responses, and implement all proposed corrective actions related to having the Watts Bar Unit 1 SPDS operational.
(4)
Vehicle Bomb Control Program (Section 13.6.9 of SSER 20)
During the period of the exemption granted in paragraph 2.D.(3) of this license, in implementing the power ascension phase of the approved initial test program, TVA shall not exceed 50% power until the requirements of 10 CFR 73.55(c)(7) and (8) are fully implemented. TVA shall submit a letter under oath or affirmation when the requirements of 73.55(c)(7) and (8) have been fully implemented.
AC Sources-Operating 3.8.1 Watts Bar-Unit 1 3.8-16 Amendment 102, 103, 132, 136 SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE FREQUENCY SR 3.8.1.21 Verify when started simultaneously from standby condition, each DG achieves, in 10 seconds, voltage 6800 V and frequency 58.8 Hz. Verify after DG fast start from standby conditions that the DG achieves steady state voltage 6800 V and 7260 V, and frequency 59.8 Hz and 60.1 Hz.
In accordance with the Surveillance Frequency Control Program
TENNESSEE VALLEY AUTHORITY DOCKET NO. 50-391 WATTS BAR NUCLEAR PLANT, UNIT 2 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 41 License No. NPF-96
- 1.
The U.S. Nuclear Regulatory Commission (the Commission) has found that:
A.
The application for amendment by Tennessee Valley Authority (TVA, the licensee) dated December 17, 2019, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions rules and regulations set forth in 10 CFR Chapter I; B.
The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.
There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D.
The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.
The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations and all applicable requirements have been satisfied.
- 2.
Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. NPF-96 is hereby amended to read as follows:
(2)
Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A as revised through Amendment No. 41 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this license. TVA shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3.
This license amendment is effective as of the date of its issuance and shall be implemented within 30 days.
FOR THE NUCLEAR REGULATORY COMMISSION Undine Shoop, Chief Plant Licensing Branch II-2 Division of operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Operating License and Technical Specifications Date of Issuance: August 19, 2020 Undine S.
Shoop Digitally signed by Undine S. Shoop Date: 2020.08.19 09:57:10 -04'00'
ATTACHMENT TO AMENDMENT NO. 41 WATTS BAR NUCLEAR PLANT, UNIT 2 FACILITY OPERATING LICENSE NO. NPF-96 DOCKET NO. 50-391 Replace page 3 of Facility Operating License No. NPF-96 with the attached revised page 3.
Replace the following page of the Appendix A Technical Specifications with the attached page.
The revised page is identified by amendment number and contain vertical lines indicating the area of change.
Remove Page Insert Page 3.8-13 3.8-13 Unit 2 Facility Operating License No. NPF-96 Amendment No. 41 C.
The license shall be deemed to contain and is subject to the conditions specified in the Commissions regulations set forth in 10 CFR Chapter I and is subject to all applicable provisions of the Act, and to the rules, regulations, and orders of the Commission now or hereafter in effect, and is subject to the additional conditions specified or incorporated below.
(1)
Maximum Power Level TVA is authorized to operate the facility at reactor core power levels not in excess of 3411 megawatts thermal.
(2)
Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A as revised through Amendment No. 41 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this license. TVA shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
(3)
TVA shall implement permanent modifications to prevent overtopping of the embankments of the Fort Loudon Dam due to the Probable Maximum Flood by June 30, 2018.
(4)
PAD4TCD may be used to establish core operating limits until the WBN Unit 2 steam generators are replaced with steam generators equivalent to the existing steam generators at WBN Unit 1.
(5)
By December 31, 2019, the licensee shall report to the NRC that the actions to resolve the issues identified in Bulletin 2012-01, Design Vulnerability in Electrical Power System, have been implemented.
(6)
The licensee shall maintain in effect the provisions of the physical security plan, security personnel training and qualification plan, and safeguards contingency plan, and all amendments made pursuant to the authority of 10 CFR 50.90 and 50.54(p).
(7)
TVA shall fully implement and maintain in effect all provisions of the Commission approved cyber security plan (CSP), including changes made pursuant to the authority of 10 CFR 50.90 and 10 CFR 50.54(p). The TVA approved CSP was discussed in NUREG-0847, Supplement 28, as amended by changes approved in License Amendment No. 7.
(8)
TVA shall implement and maintain in effect all provisions of the approved fire protection program as described in the Fire Protection Report for the facility, as described in NUREG-0847, Supplement 29, subject to the following provision:
AC Sources - Operating 3.8.1 Watts Bar - Unit 2 3.8-13 Amendment 36, 41 SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE FREQUENCY SR 3.8.1.20 Verify during idle operation that any automatic or emergency start signal disables the idle start circuitry and commands the engine to full speed.
In accordance with the Surveillance Frequency Control Program SR 3.8.1.21 Verify when started simultaneously from standby condition, each DG achieves, in 10 seconds, voltage 6800 V and frequency 58.8 Hz. Verify after DG fast start from standby conditions that the DG achieves steady state voltage 6800 V and 7260 V, and frequency 59.8 Hz and 60.1 Hz.
In accordance with the Surveillance Frequency Control Program
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NOS. 136 AND 41 TO FACILITY OPERATING LICENSE NOS. NPF-90 AND NPF-96 TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT, UNITS 1 AND 2 DOCKET NOS. 50-390 AND 50-391
1.0 INTRODUCTION
By letter dated December 17, 2019 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML19353C089), the Tennessee Valley Authority (TVA, the licensee),
submitted a request for changes to the Watts Bar Nuclear Plant, Units 1 and 2 (Watts Bar 1 and 2), Technical Specifications (TSs). The requested changes would modify the Watts Bar 1 and 2, TS 3.8.1, AC [Alternating Current] Sources - Operating, to delete Surveillance Requirement (SR) 3.8.1.22. The proposed change would remove the requirement to verify the operability of the automatic transfer from a Unit Service Station Transformer (USST) to Common Station Service Transformer (CSST) A or B at the associated unit board. The offsite circuit alignment that credits CSST A or B as a qualified power source when the associated 6.9 kilovolt (kV) shutdown boards (SDBDs) are powered from a USST with automatic transfer to the associated CSST (A or B) at the respective unit boards will no longer be included in the Watts Bar 1 and 2 design bases.
2.0 REGULATORY EVALUATION
2.1
System Description
As described in the Watts Bar 1 and 2, Updated Final Safety Analysis Report (UFSAR),
Section 8, Electric Power (ADAMS Accession No. ML19336A068), the AC electrical power distribution system is shared between Watts Bar 1 and 2 and consists of the offsite power sources and the onsite standby power sources. Offsite power is supplied to the 161-kV transformer yard by two electrically and physically separated circuits through CSSTs A, B, C, and D. The Class 1E power system is normally supplied from CSSTs C and D. A maintenance feed is available to provide offsite power from CSSTs A and B to the Class 1E power systems, which can be used when CSST C or D is out of service during any operating mode.
The licensees December 17, 2019, letter states that:
The low voltage side of CSSTs A and B powers non-safety-related 6.9 kV station service buses, which include the 6.9 kV common, unit, and reactor coolant pump boards. CSST A is normally aligned to provide offsite power to 6.9 kV common board A and alternate power to 6.9 kV unit boards 1A, 1C, 2A, and 2C. CSST B provides offsite power to 6.9 kV common board B and alternate power to 6.9 kV unit boards 1B, 1D, 2B, and 2D. When CSST C is not available, CSST B can be aligned manually to provide power to the Train A 6.9 kV SDBDs 1A-A and 2A-A.
CSST C provides normal offsite power from the secondary Y winding to 6.9 kV SDBD 1A-A and from the secondary X winding to 6.9 kV SDBD 2A-A. In addition, this transformer provides alternate (offsite) power from the secondary X winding to 6.9 kV SDBD 1B-B and from the secondary Y winding to 6.9 kV SDBD 2B-B. CSST D provides normal offsite power from the secondary X winding to 6.9 kV SDBD 1B-B and from the secondary Y winding to 6.9 kV SDBD 2B-B. In addition, this transformer provides alternate (offsite) power from the secondary Y winding to 6.9 kV SDBD 1A-A from the secondary X winding to 6.9 kV SDBD 2AA.
The four 6.9 kV SDBDs that are arranged electrically into four power trains (two per unit) with two boards associated with each load group in each unit.
Therefore, each 161kV line associated with CSST C and D is the normal feed for one train of SDBDs and the alternate feed for the other train of SDBDs. The other transformers (CSST A and B, one at a time) on each line supply power to the 6.9 kV non-safety-related unit and common boards and can provide alternate power the 6.9 kV SDBDs, if they are tied to the unit boards through the maintenance feeder.
2.2 Description of Proposed Change The licensee proposed to revise Watts Bar 1 and 2, TS 3.8.1, by deleting SR 3.8.1.22, as follows (deleted text shown in strikethrough):
SURVEILLANCE FREQUENCY SR 3.8.1.22
NOTES --------------------
- 1. For the 1B and 1C Unit Boards, this Surveillance shall not normally be performed in MODE 1 or 2. However, this Surveillance may be performed to reestablish OPERABILITY provided an assessment determines the safety of the plant is maintained or enhanced. Credit may be taken for unplanned events that satisfy this SR.
- 2. Transfer capability is only required to be met for 6.9kV Unit Boards that require normal and alternate power supplies.
Verify automatic transfer of each 6.9kV Unit Board 1B, 1C, 2B and 2C power supply from the normal power supply to the alternate power supply.
18 months The wording to be deleted, shown above reflects that in the Watts Bar 1 TSs. The wording to be deleted in the Watts Bar 2 TSs is similar, except that Note 1 reflects the 2B and 2C Unit Boards.
2.3 Applicable Regulatory Requirements and Guidance The U.S. Nuclear Regulatory Commission (NRC) staff reviewed the licensees application to determine whether (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) activities proposed will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or the health and safety of the public. The NRC staff considered the following regulatory requirements, guidance, and licensing and design-basis information during its review of the proposed changes.
Section 50.36(c) of Title 10 of the Code of Federal Regulations (10 CFR) requires, in part, that the TSs include items in the following categories related to station operation: (1) safety limits, limiting safety system settings, and limiting control settings; (2) Limiting Conditions for Operation (LCOs); (3) SRs; (4) design features; and (5) administrative controls.
Section 50.36(c)(3) of 10 CFR states, in part, that SRs are requirements relating to test, calibration, or inspection to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the LCOs will be met.
Appendix A, General Design Criteria (GDC) For Nuclear Power Plants, to 10 CFR Part 50, Domestic Licensing of Production and Utilization Facilities, establishes the minimum requirements for the principal design criteria for water-cooled nuclear power plants. The following GDC are applicable for this review:
GDC 5, "Sharing of structures, systems, and components," requires that structures, systems, and components important to safety shall not be shared among nuclear power units unless it can be shown that such sharing will not significantly impair their ability to perform their safety functions, including, in the event of an accident in one unit, an orderly shutdown and cooldown of the remaining units. At Watts Bar 1 and 2, the two units share offsite power sources.
GDC 17, "Electric power systems," requires, in part, that nuclear power plants have an onsite and an offsite electric power system to permit the functioning of structures, systems, and components that are important to safety. The offsite power system is required to be supplied by two physically independent circuits that are designed and located so as to minimize, to the extent practical, the likelihood of their simultaneous failure under operating and postulated accident and environmental conditions. In addition, this criterion requires provisions to minimize the probability of losing electric power from the remaining electric power supplies as a result of loss of power from the unit, the offsite transmission network, or the onsite power supplies.
3.0 TECHNICAL EVALUATION
The NRC staff evaluated the licensees application to determine if the proposed changes are consistent with the guidance, regulations, and plant-specific design and licensing basis information discussed in Sections 2.1 and 2.3 of this safety evaluation.
3.1 Deletion of SR 3.8.1.22 Watts Bar 1 and 2 have two shared offsite power sources through CSSTs C and D that satisfy GDC 17 and GDC 5 requirements. By letters dated September 29 and October 22, 2015 (ADAMS Accession Nos. ML15225A094 and ML15251A587, respectively), the NRC staff approved the alignment of offsite circuits through CSST A or B as a GDC 17 offsite power source for Watts Bar 1 and 2, respectively, when the unit board and associated SDBDs are powered from a USST and CSST A or B is automatically transferred onto the board on a unit trip.
In its December 17, 2019, license amendment request, the licensee stated that the alignment of the offsite power source through CSST A or B by automatic transfer from the USST at the associated unit board did not meet GDC 17 requirements because a voltage transient could disconnect the offsite power source during the automatic transfer from the USST following an event. The licensee verified that this offsite power alignment had not been used at Watts Bar 1 and 2 and took corrective actions to preclude use of this system alignment. The licensee then removed this alignment from the Watts Bar 1 and 2 design bases.
The NRC staff notes that removing the alignment of the offsite power source through CSST A or B when an automatic transfer from the USST to the CSST A or B occurs at the associated unit board does not impact the GDC 17 offsite power sources through CSSTs C and D. As such, the Watts Bar 1 and 2 offsite power system will continue to meet the requirements of GDC 17 and GDC 5 with the offsite power sources through the CSSTs C and D.
The licensee proposed to remove SR 3.8.1.22, which verifies the operability of the automatic transfer from a unit board to CSST A or B, when the associated unit board requires normal and alternate power sources. The Watts Bar 1 and 2 TSs currently allow the alignment of the offsite circuits through CSST A or B to the unit board and SDBDs by automatic transfer from USST to CCST A or B as an alternate power source to meet TS LCO 3.8.1 while CSST C or D is out of service. Because the alignment of CSST A or B to the SDBDs by automatic transfer from the USST to the CSST A or B at the associated unit board has been removed from the Watts Bar 1 and 2 design bases, there is no longer a need to verify the operability of the automatic transfer from the USST to CSST A or B at the unit boards. Therefore, the NRC staff finds that the deletion of SR 3.8.1.22 is acceptable because, with the removal of the above-mentioned alignment of offsite power source through CSST A or B, SR 3.8.1.22 is no longer needed to meet the requirements of 10 CFR 50.36(c)(3).
4.0 STATE CONSULTATION
In accordance with the Commissions regulations, the Tennessee State official was notified of the proposed issuance of the amendment on June 10, 2020. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendments change a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. Standards for Protection Against Radiation and changes a SR. The NRC staff has determined that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission previously issued a proposed finding that the amendment involves no significant hazards consideration, published in the Federal Register on February 25, 2020 (85 FR 10734), and there has been no public comment on such finding. Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
6.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) there is reasonable assurance that such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
7.0 REFERENCES
Principal Contributor: Hari Kodali Date: August 19, 2020
- Via e-mail OFFICE NRR/DORL/LPL2-2/PM* NRR/DORL/LPL2-2/LA*
NRR/DEX/EEOB/BC*
NAME MWentzel BAbeywickrama BTitus DATE 06/18/2020 06/15/2020 06/04/2020 OFFICE NRR/DSS/STSB/BC*
OGC (NLO w/comments) NRR/DORL/LPL2-2/BC*
NAME VCusumano STurk UShoop DATE 06/18/2020 06/30/2020 08/19/2020 OFFICE NRR/DORL/LPL2-2/PM*
NAME MWentzel DATE 08/19/2020