ML080370065
ML080370065 | |
Person / Time | |
---|---|
Site: | Susquehanna ![]() |
Issue date: | 02/19/2008 |
From: | Richard Guzman NRC/NRR/ADRO/DORL/LPLI-1 |
To: | Mckinney B Susquehanna |
Guzman R | |
References | |
TAC MD4766 | |
Download: ML080370065 (6) | |
Text
February 19, 2008 Mr. Britt T. McKinney Sr. Vice President and Chief Nuclear Officer PPL Susquehanna, LLC 769 Salem Blvd., NUCSB3 Berwick, PA 18603-0467
SUBJECT:
SUSQUEHANNA STEAM ELECTRIC STATION, UNIT 2 - ISSUANCE OF AMENDMENT RE: ELECTRICAL POWER SYSTEMS TECHNICAL SPECIFICATION 3.8.1 (TAC NO. MD4766)
Dear Mr. McKinney:
The Commission has issued the enclosed Amendment No. 225 to Facility Operating License No.
NPF-22 for the Susquehanna Steam Electric Station, Unit 2 (SSES 2). This amendment consists of changes to the Technical Specifications (TSs) in response to your application dated March 2, 2007, as supplemented by letter dated December 5, 2007.
This amendment adds an ACTIONS Note 3 to the SSES 2 TS 3.8.1, AC Sources - Operating, to allow a Unit 1 4160 volt subsystem to be de-energized and removed from service to perform bus maintenance.
A copy of our safety evaluation is also enclosed. The Notice of Issuance will be included in the Commission's next regular Biweekly Federal Register Notice.
Sincerely,
/RA/
Richard V. Guzman, Senior Project Manager Plant Licensing Branch I-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-388
Enclosures:
- 1. Amendment No. 225 to License No. NPF-22
- 2. Safety Evaluation cc w/encls: See next page
February 19, 2008 Mr. Britt T. McKinney Sr. Vice President and Chief Nuclear Officer PPL Susquehanna, LLC 769 Salem Blvd., NUCSB3 Berwick, PA 18603-0467
SUBJECT:
SUSQUEHANNA STEAM ELECTRIC STATION, UNIT 2 - ISSUANCE OF AMENDMENT RE: ELECTRICAL POWER SYSTEMS TECHNICAL SPECIFICATION 3.8.1 (TAC NO. MD4766)
Dear Mr. McKinney:
The Commission has issued the enclosed Amendment No. 225 to Facility Operating License No.
NPF-22 for the Susquehanna Steam Electric Station, Unit 2 (SSES 2). This amendment consists of changes to the Technical Specifications (TSs) in response to your application dated March 2, 2007, as supplemented by letter dated December 5, 2007.
This amendment adds an ACTIONS Note 3 to the SSES 2 TS 3.8.1, AC Sources - Operating, to allow a Unit 1 4160 volt subsystem to be de-energized and removed from service to perform bus maintenance.
A copy of our safety evaluation is also enclosed. The Notice of Issuance will be included in the Commission's next regular Biweekly Federal Register Notice.
Sincerely,
/RA/
Richard V. Guzman, Senior Project Manager Plant Licensing Branch I-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-388
Enclosures:
- 1. Amendment No. 225 to License No. NPF-22
- 2. Safety Evaluation cc w/encls: See next page DISTRIBUTION PUBLIC LPLI-1 R/F RidsNrrDorlLpl1-1 RidsNrrPMRGuzman RidsNrrLASLittle RidsOGCRp RidsNrrDeEeeb RidsNrrDorlDpr GHill(4) RidsAcrsAcnwMailCenter SRay RidsRgn1MailCenter ADAMS Accession Numbers: Package: ML080500282 ; Amendment: ML080370065; Tech Specs: ML080500268
- SE inputs provided by memo. No substantive changes made.
OFFICE LPLI-1/PM LPLI-1/LA DE/EEEB/BC OGC LPLI-1/BC NAME RGuzman SLittle GWilson* LSubin MKowal DATE 2/13/08 2/13/08 12/20/07 SE DTD 2/14/08 2/15/08 OFFICIAL RECORD COPY
Susquehanna Steam Electric Station, Unit Nos. 1 and 2 cc:
Cornelius J. Gannon Bryan A. Snapp, Esq Vice President - Nuclear Operations Assoc. General Counsel PPL Susquehanna, LLC PPL Services Corporation 769 Salem Blvd., NUCSB3 Two North Ninth Street, GENTW3 Berwick, PA 18603-0467 Allentown, PA 18101-1179 Robert M. Paley Supervisor - Document Control Services General Manager - Plant Support PPL Susquehanna, LLC PPL Susquehanna, LLC Two North Ninth Street, GENPL4 769 Salem Blvd., NUCSB2 Allentown, PA 18101-1179 Berwick, PA 18603-0467 Richard W. Osborne Rocco R. Sgarro Allegheny Electric Cooperative, Inc.
Manager - Nuclear Regulatory Affairs 212 Locust Street PPL Susquehanna, LLC P.O. Box 1266 Two North Ninth Street, GENPL4 Harrisburg, PA 17108-1266 Allentown, PA 18101-1179 Director, Bureau of Radiation Protection Supervisor - Pennsylvania Department of Nuclear Regulatory Affairs Environmental Protection PPL Susquehanna, LLC Rachel Carson State Office Building 769 Salem Blvd., NUCSA4 P.O. Box 8469 Berwick, PA 18603-0467 Harrisburg, PA 17105-8469 Michael H. Crowthers Senior Resident Inspector Supervising Engineer U.S. Nuclear Regulatory Commission Nuclear Regulatory Affairs P.O. Box 35, NUCSA4 PPL Susquehanna, LLC Berwick, PA 18603-0035 Two North Ninth Street, GENPL4 Allentown, PA 18101-1179 Regional Administrator, Region 1 U.S. Nuclear Regulatory Commission Ronald E. Smith 475 Allendale Road General Manager - Site Preparedness King of Prussia, PA 19406 and Services PPL Susquehanna, LLC Board of Supervisors 769 Salem Blvd., NUCSA4 Salem Township Berwick, PA 18603-0467 P.O. Box 405 Berwick, PA 18603-0035 Manager - Quality Assurance PPL Susquehanna, LLC Dr. Judith Johnsrud 769 Salem Blvd., NUCSB2 National Energy Committee Berwick, PA 18603-0467 Sierra Club 443 Orlando Avenue Luis A. Ramos State College, PA 16803 Community Relations Manager, Susquehanna PPL Susquehanna, LLC 634 Salem Blvd., SSO Berwick, PA 18603-0467
PPL SUSQUEHANNA, LLC ALLEGHENY ELECTRIC COOPERATIVE, INC.
DOCKET NO. 50-388 SUSQUEHANNA STEAM ELECTRIC STATION, UNIT 2 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 225 License No. NPF-22
- 1. The Nuclear Regulatory Commission (the Commission or the NRC) having found that:
A. The application for the amendment filed by PPL Susquehanna, LLC, dated March 2, 2007, as supplemented on December 5, 2007, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's 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 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 Commission's regulations set forth in 10 CFR Chapter I; 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 Commission's 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 the Facility Operating License No. NPF-22 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. 225 and the Environmental Protection Plan contained in Appendix B, are hereby incorporated in the license. PPL Susquehanna, LLC shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3. This license amendment is effective as of its date of issuance and shall be implemented within 30 days.
FOR THE NUCLEAR REGULATORY COMMISSION
/RA/
Mark G. Kowal, Chief Plant Licensing Branch I-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the License and Technical Specifications Date of Issuance: February 19, 2008
ATTACHMENT TO LICENSE AMENDMENT NO. 225 FACILITY OPERATING LICENSE NO. NPF-22 DOCKET NO. 50-388 Replace the following page of the Facility Operating License with the attached revised page.
The revised page is identified by amendment number and contains marginal lines indicating the areas of change.
REMOVE INSERT 3 3 Replace the following page of the Appendix A Technical Specifications with the attached revised page. The revised page is identified by amendment number and contains marginal lines indicating the areas of change.
REMOVE INSERT TS/3.8.1 TS/3.8.1
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 225 TO FACILITY OPERATING LICENSE NO. NPF-22 PPL SUSQUEHANNA, LLC ALLEGHENY ELECTRIC COOPERATIVE, INC.
SUSQUEHANNA STEAM ELECTRIC STATION, UNIT 2 DOCKET NO. 50-388
1.0 INTRODUCTION
By letter dated March 2, 2007, Agencywide Documents Access and Management System Accession No. ML070720545, as supplemented by letter dated December 5, 2007 (ML073470232), PPL Susquehanna, LLC (PPL, the licensee), requested changes to the Technical Specifications (TSs) for Susquehanna Steam Electric Station, Unit 2 (SSES Unit 2).
The proposed changes would add an ACTION Note 3 to the SSES Unit 2 TS 3.8.1, AC Sources
[alternating current] - Operating, to allow a Unit 1 4160 volt (V) subsystem to be de-energized and removed from service to perform bus maintenance.
The supplemental letter dated December 5, 2007, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the Nuclear Regulatory Commission (NRC) staffs original proposed no significant hazards consideration determination as published in the Federal Register on August 14, 2007 (72 FR 45459).
2.0 REGULATORY EVALUATION
Title 10 of the Code of Federal Regulations (10 CFR) Appendix A of Part 50, General Design Criterion (GDC) 17, Electric Power Systems, requires, in part, that nuclear power plants have onsite and offsite electric power systems to permit the functioning of structures, systems, and components that are important to safety. The onsite system is required to have sufficient independence, redundancy, and testability to perform its safety function, assuming a single failure. Electric power from the transmission network to the onsite electric distribution 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 a loss of power from the unit, the offsite transmission network, or the onsite power supplies.
GDC 5, Sharing of Structures, Systems, and Components, states 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.
In 10 CFR 50.36, the Commission established its regulatory requirements related to the content of TSs. In doing so, the Commission placed emphasis on those matters related to the prevention of accidents and the mitigation of accident consequences. Pursuant to 10 CFR 50.36, TSs are required to include items in the following five specific categories related to station operation: (1) safety limits, limiting safety system settings, and limiting control settings; (2) limiting conditions for operation (LCOs); (3) surveillance requirements; (4) design features; and (5) administrative controls. However, the rule does not specify the particular requirements to be included in a plants TSs.
3.0 TECHNICAL EVALUATION
3.1 Description of SSES Electrical Distribution System SSES Units 1 and 2 each contain an onsite Class 1E alternating current (AC) electrical power distribution system that is divided into redundant and independent AC electrical power distribution subsystems. Each unit has four independent load group channels (four 4160 V engineered safeguards system (ESS) buses) and any combination of three out of four load groups meets the design basis requirements. The four Class 1E load groups are subgrouped generally to form two divisions for meeting the design-basis of one out of two engineered safety features (ESF) load requirements. In addition, four shared diesel generators (DGs) can be connected to the 4160 V buses to provide emergency power if offsite power is unavailable.
Each DG supplies power to one ESS bus in SSES Unit 1 and one ESS bus in SSES Unit 2.
Some loads, energized only from the SSES Unit 1 AC distribution system, are shared between both units. The common equipment includes Emergency Service Water (ESW), Standby Gas Treatment System (SGTS), Control Room Emergency Outside Air Supply (CREOAS), and Control Room Floor Cooling. Thus, the SSES Unit 1 AC distribution system is needed to support operation of SSES Unit 2 equipment.
3.2 Evaluation of Proposed Changes Currently, when the SSES Unit 1 4160 V subsystem is de-energized for bus maintenance, the licensee enters LCO 3.8.1 Conditions A, B, and D because an offsite power supply and a DG would be declared inoperable. Condition A is for the offsite power source being declared inoperable and Condition B is for the DG being unable to connect to its respective ESS bus and accept required loads. Entry into Condition D would be required since individual redundancy is lost in both the offsite electrical power system and the onsite AC electrical power system.
Condition D currently allows a 12-hour Completion Time, which the licensee contends is insufficient to perform the required bus-related maintenance and inspection.
The licensee proposed revising SSES Unit 2 TS 3.8.1 to add a new ACTIONS Note 3 that describes the condition when SSES Unit 2 is operating in Modes 1, 2, or 3, SSES Unit 1 is in Mode 4 or 5, and an SSES Unit 1 4160 V bus subsystem is de-energized and removed from service to perform bus maintenance. The licensee stated that the proposed change is needed to provide sufficient time to perform bus maintenance on a 4160 V bus. During the time that a 4160 V bus is de-energized, the licensee stated that both offsite power supplies would continue
to provide power to the remaining 4160 V subsystems on both units. Additionally, the associated DG is available to supply power to the associated SSES Unit 2 4160 V subsystem and the other 3 DGs remain capable of performing their safety functions, supplying the loads on the associated 4160 V subsystems. Therefore, the new ACTIONS Note 3 establishes an exception to the definition of an operable offsite circuit and an operable DG, for performance of bus maintenance only. With the new ACTIONS note, the licensee would not be required to enter into SSES Unit 2 TS 3.8.1 Conditions A, B, and D when de-energizing a Unit 1 4160 V subsystem solely for the purpose of bus maintenance. Hence, neither the primary or alternate offsite power source nor the associated DG will be declared inoperable.
The licensee further stated that SSES plant procedures govern de-energizing the 4160 V bus, associated offsite and DG feeder circuits for inspection and maintenance. In addition, the licensee noted that procedures also provide steps to complete restoration of the bus and feeder circuits. The plant schedule estimates 50 - 60 hours6.944444e-4 days <br />0.0167 hours <br />9.920635e-5 weeks <br />2.283e-5 months <br /> for these activities. For bus maintenance and inspection, LCO 3.8.7 Condition C, Distribution Systems - Operating, is required to be entered, as stated in Note 3, and has a Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The licensee would be required to enter into LCO 3.8.1 Condition D for maintenance and inspection of the DG power supply cubicle and the offsite power supply cubicles.
The common loads required for SSES Unit 2 operation, powered by SSES Unit 1 ESS buses, include ESW, SGTS, CREOAS, and Control Room Floor Cooling. Since bus maintenance activities on SSES Unit 1 only affect the availability of one bus, the three remaining SSES Unit 1 4160 V ESS buses remain capable of supplying the required loads for SSES Unit 2. Each ESS bus has an ESW pump. ESS bus 1C provides power to a Control Structure Chiller and an ESS load center that provides 480 V power to the SGTS, Control Room Cooling, and CREOAS.
Redundant equipment is available on ESS bus 1D. Therefore, a redundant bus on SSES Unit 1 would be capable of supplying the required loads for SSES Unit 2 if one bus is de-energized for maintenance.
When one SSES Unit 1 ESS bus is out of service, both the primary and alternate offsite sources, through startup transformers, would remain energized and the 4 DGs would remain capable of supplying the electrical AC power requirements for the unaffected SSES Unit 1 ESS buses and all the SSES Unit 2 ESS buses. Thus, three power supplies would be operable and available for the remaining 4160 V ESS buses.
The licensee stated that an SSES Unit 1 bus outage would not prevent any DG from connecting to its associated SSES Unit 2 AC distribution subsystem. In the case of a design basis loss-of-coolant accident and loss of offsite power event during an SSES Unit 1 bus outage, the DG would start and load as necessary to provide power to loads needed to mitigate the accident. In the event of a loss of offsite power on one or both units, the DGs would provide power to loads necessary to shutdown the reactor and maintain them in a safe shutdown condition. SSES remains in conformance with GDC 5 since the SSES Unit 1 AC Distribution system is shared between both units and is sufficient to operate the ESFs of one unit and the safe shutdown loads of the other unit. In addition, the DGs are shared systems and the loss of one DG will not impair the capability to safely shutdown both units, as three DGs remain available. Similarly, two offsite power supplies are shared and the capacity of each is sufficient to operate the ESFs of one unit and safe shutdown of the other unit.
GDC 17 is satisfied as either of the two offsite power supplies or any three of the four DGs have sufficient capability to operate ESF loads in the event of a postulated accident in one unit and a safe shutdown in the other unit. Furthermore, an additional DG is available and capable of supplying the emergency loading for any one of the other four DGs. However, this DG must be manually aligned to replace one of the four DGs.
The NRC staff requested that the licensee provide assurance that no maintenance or testing that affects the reliability of the remaining trains would be scheduled during the SSES Unit 1 bus maintenance and if any testing or maintenance activities were required to be performed, then an evaluation will be performed under 10 CFR 50.65(a)(4). Regulatory Commitment 1, listed in of the licensees December 5, 2007 letter, addresses this issue. The NRC staff finds the regulatory commitment acceptable.
The NRC staff requested assurance that the bus maintenance would be avoided during seasons when the probability of severe weather or grid stress conditions is high or forecasted to be high.
In its December 5, 2007, response, the licensee indicated that SSES Unit 1 4160 V bus maintenance is scheduled during an SSES Unit 1 outage, which is normally scheduled during the spring when the probability of severe weather or grid stress conditions is not high or not forecasted to be high. In addition, the licensee stated that the transmission operator, PJM
[Pennsylvania New Jersey Maryland Interconnection LLC (Mid-Atlantic region power pool)],
would avoid maintenance during high grid stress times. This is consistent with the licensees Generic Letter (GL) 2006-02, Grid Reliability and the Impact on Plant Risk and the Operability of Offsite Power, response. The NRC staff finds the response acceptable.
Furthermore, the NRC staff requested that during the bus maintenance, there should be communications with the system load dispatcher. For example, the system load dispatcher should be contacted once per day to ensure no significant grid perturbations are expected and additionally, the system load dispatcher should inform the plant operator if conditions change during bus maintenance. In their December 5, 2007, letter, the licensee discussed SSES procedures that are in place for communications with the transmission operator. The communication protocols have been demonstrated to be effective at managing risk, reducing risk by restoring out of service equipment, and rescheduling work due to emergent issues as they occur. Thus, existing procedures ensure that communications are in place to manage risk during the bus maintenance.
The NRC staff requested that the licensee address the issue of avoiding component testing or maintenance of safety systems and important non-safety equipment that increases the likelihood of a plant transient or loss of offsite power and also, not allowing any discretionary switchyard maintenance. In its December 5, 2007, letter, the licensee stated that grid risk sensitive maintenance activities are rescheduled as required based on information received from the transmission operator. When the maintenance activities cannot be rescheduled (nondiscretionary), contingencies are put in place. This is consistent with the licensees GL 2006-02 response. The NRC staff finds the response acceptable.
In addition, to ensure that systems powered from the remaining 4160 V buses are operable, the NRC staff requested assurance that TS requirements of verification that the required systems, subsystems, trains, components, and devices that depend on the remaining 4160 V buses are operable and that positive measures would be provided to preclude subsequent testing or maintenance activities on these systems, subsystems, trains, components, and devices. In
Attachment 2 of the December 5, 2007, letter, the licensee provided as a regulatory commitment that during the application of SSES Unit 2 TS 3.8.1 Note 3, the required systems, subsystems, trains, components, and devices that depend on the remaining 4160 V buses will be verified to be operable.
The NRC staff informed the licensee that safety-related steam driven pumps, high-pressure core injection (HPCI), and reactor core isolation cooling (RCIC) pumps, should be controlled as protected equipment, and not be taken out of service for planned maintenance while an SSES Unit 1 4160 V bus is out of service for extended maintenance. The licensee, in its December 5, 2007, letter, provided the following as a regulatory commitment:
During the application of Unit 2 TS 3.8.1 Note 3, the Unit 2 safety-related HPCI and RCIC pumps will be controlled as protected equipment and will not be taken out of service for planned maintenance while a Unit 1 4160 V bus is out of service for extended maintenance.
The NRC staff finds that the above regulatory commitment addresses the concern.
3.3 Conclusion Based on the above evaluation, redundant power supplies are available, and the licensee has demonstrated that the design will continue to meet the requirements of GDC 5, GDC 17, and 10 CFR 50.36. Therefore, the proposed change is acceptable.
4.0 STATE CONSULTATION
In accordance with the Commissions regulations, the Pennsylvania State official was notified of the proposed issuance of the amendment. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves 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 has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding issued on August 14, 2007 (72 FR 45459). Accordingly, the amendment meets 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 amendment.
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) such activities will be conducted in compliance with the Commissions 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.
Principal Contributor: S. Ray Date: February 19, 2008