PLA-8187, Application to Revise Technical Specifications to Adopt TSTF-599, Revision 1, Eliminate Periodic Surveillance Test of Simultaneous Start of Redundant Diesel Generators
| ML25337A031 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 12/03/2025 |
| From: | Casulli E Talen Energy |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| PLA-8187 | |
| Download: ML25337A031 (0) | |
Text
Edward Casulli Susquehanna Nuclear, LLC Site Vice President 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.3795 Fax 570.542.1504 Edward.Casulli@TalenEnergy.com December 03, 2025 Attn: Document Control Desk 10 CFR 50.90 U. S. Nuclear Regulatory Commission Washington, DC 20555-0001 SUSQUEHANNA STEAM ELECTRIC STATION PROPOSED AMENDMENT TO LICENSES NPF-14 AND NPF-22: APPLICATION TO REVISE TECHNICAL SPECIFICATIONS TO ADOPT TSTF-599, REVISION 1, ELIMINATE PERIODIC SURVEILLANCE TEST OF SIMULTANEOUS START OF REDUNDANT DIESEL GENERATORS PLA-8187 Docket No. 50-387 and 50-388 Pursuant to 10 CFR 50.90, Susquehanna Nuclear, LLC (Susquehanna), is submitting a request for an amendment to the Technical Specifications (TS) for the Susquehanna Steam Electric Station (SSES), Units 1 and 2, Facility Operating License numbers NPF-14 and NPF-22.
Susquehanna requests adoption of TSTF-599, Revision 1, "Eliminate Periodic Surveillance Test of Simultaneous Start of Redundant Diesel Generators," which is an approved change to the Standard Technical Specifications (STS), into the SSES, Units 1 and 2 TS. The proposed change eliminates the periodic Surveillance Requirement (SR) to verify that all required diesel generators (DGs) achieve rated frequency and voltage within the specified time period when started simultaneously.
The enclosure provides a description and assessment of the proposed changes. Attachment 1 provides the existing TS pages marked to show the proposed changes. Attachment 2 provides revised (clean) TS pages. Attachment 3 provides the existing TS Bases pages marked to show revised text associated with the proposed TS changes and is provided for information only.
Susquehanna requests that the amendment be reviewed under the Consolidated Line Item Improvement Process (CLIIP). Approval of the proposed amendment is requested within 6 months of completion of the NRCs acceptance review. Once approved, the amendment shall be implemented within 90 days.
In accordance with 10 CFR 50.91, Susquehanna is providing a copy of this application, with attachments, to the designated Commonwealth of Pennsylvania state official.
TALEN~
ENERGY Document Control Desk PLA-8187 Both the Plant Operations Review Committee and the Nuclear Safety Review Board have reviewed the proposed changes.
There are no new or revised regulatory commitments contained in this submittal.
Should you have any questions regarding this submittal, please contact Ms. Melisa Krick, Manager - Nuclear Regulatory Affairs, at (570) 542-1818.
I declare under penalty of perjury that the foregoing is true and correct.
Executed on December 03, 2025.
E. Casulli
Enclosure:
Description and Assessment Attachments:
- 1. Proposed Technical Specification Changes (Mark-Up)
- 2. Revised Technical Specification Pages
- 3. Proposed Technical Specification Bases Changes (Mark-Up) - For Information Only Copy: NRC Region I Mr. R. Wehrmann, NRC Senior Resident Inspector Mr. R. Guzman, NRC Project Manager Mr. M. Shields, PA DEP/BRP
Enclosure to PLA-8187 Description and Assessment
- 1.
DESCRIPTION
- 2.
ASSESSMENT 2.1 Applicability of Safety Evaluation 2.2 Variations
- 3.
REGULATORY ANALYSIS 3.1 No Significant Hazards Consideration Analysis 3.2 Conclusion
- 4.
ENVIRONMENTAL CONSIDERATION
Enclosure to PLA-8187 Page 1 of 4 SUSQUEHANNA ASSESSMENT
- 1.
Description Susquehanna Nuclear, LLC (Susquehanna), requests adoption of TSTF-599, Revision 1, "Eliminate Periodic Surveillance Test of Simultaneous Start of Redundant Diesel Generators,"
which is an approved change to the Standard Technical Specifications (STS), into the Susquehanna Steam Electric Station (SSES) Units 1 and 2 Technical Specifications (TS). The proposed change eliminates the periodic Surveillance Requirement (SR) to verify that all required diesel generators (DGs) achieve rated frequency and voltage within the specified time period when started simultaneously.
- 2.
Assessment 2.1 Applicability of Safety Evaluation Susquehanna has reviewed the safety evaluation for TSTF-599 provided to the Technical Specifications Task Force in a letter dated May 05, 2025. This review included the NRC staffs evaluation, as well as the information provided in TSTF-599. Susquehanna has concluded that the justifications presented in TSTF-599 and the safety evaluation prepared by the NRC staff are applicable to SSES Units 1 and 2 and justify this amendment for the incorporation of the changes to the SSES Units 1 and 2 TS.
2.2 Variations Susquehanna is proposing the following variations from the TS change described in TSTF-599:
The SSES Units 1 and 2 TS SR 3.8.1.20 contain a plant specific note pertaining to the E DG.
The note identifies the SR does not have to be performed with the E DG substituted for any DG. Removal of this note is administrative and does not affect the applicability of TSTF-599 to the SSES Units 1 and 2 TS.
The SSES Units 1 and 2 TS do not reference SR 3.8.1.20 in SR 3.8.2.1. Therefore, no change to SR 3.8.2.1 is necessary. This does not affect the justification of the change.
Enclosure to PLA-8187 Page 2 of 4
- 3.
Regulatory Analysis 3.1 No Significant Hazards Consideration Analysis Susquehanna Nuclear, LLC (Susquehanna), requests adoption of TSTF-599, Revision 1, "Eliminate Periodic Surveillance Test of Simultaneous Start of Redundant Diesel Generators,"
which is an approved change to the Standard Technical Specifications (STS), into the Susquehanna Steam Electric Station (SSES) Units 1 and 2 Technical Specifications (TS). The proposed change eliminates the periodic Surveillance Requirement (SR) to verify that all required diesel generators (DGs) achieve rated frequency and voltage within the specified time period when started simultaneously.
Susquehanna has evaluated if a significant hazards consideration is involved with the proposed amendment(s) by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:
- 1.
Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?
Response: No The proposed change eliminates a periodic Surveillance test which verifies that all required diesel generators (DGs) achieve rated frequency and voltage within the specified time period when started simultaneously. Simultaneous start of the redundant DGs is not an initiator of any accident previously evaluated. The fast start of the DGs is verified by other Surveillance tests and historical performance of the simultaneous test has always been successful (1). As a result, the DG reliability and the attendant effect on the consequences of any accident previously evaluated are not affected.
Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.
(1) Note: During performance of SR 3.8.1.20 on May 20, 2016, acceptance criteria was not met due to the B DG failing to start within 10 seconds. This condition was not attributed to starting independence and would have been present in any start demand.
SR 3.8.1.20 was successfully reperformed on May 23, 2016. All other previous performances of SR 3.8.1.20 were completed successfully with acceptance criteria met.
- 2.
Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?
Response: No
Enclosure to PLA-8187 Page 3 of 4 The proposed change eliminates a periodic Surveillance test which verifies that all required diesel generators (DGs) achieve rated frequency and voltage within the specified time period when started simultaneously. No new or different accidents result from the proposed change. The changes do not involve a physical alteration of the plant (i.e., no new or different type of equipment will be installed) or a change in the methods governing normal plant operation. In addition, the changes do not impose any new or different requirements. The changes do not alter assumptions made in the safety analysis.
The proposed changes are consistent with the safety analysis assumptions and current plant operating practice.
Therefore, the proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.
- 3.
Does the proposed amendment involve a significant reduction in a margin of safety?
Response: No The proposed change eliminates a periodic Surveillance test which verifies that all required diesel generators (DGs) achieve rated frequency and voltage within the specified time period when started simultaneously. The proposed change does not adversely affect existing plant safety margins, or the reliability of the equipment assumed to operate in the safety analysis. As such, there are no changes being made to safety analysis assumptions, safety limits or limiting safety system settings that would adversely affect plant safety as a result of the proposed change.
Therefore, the proposed change does not involve a significant reduction in a margin of safety.
Based on the above, Susquehanna concludes that the proposed change presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.
Enclosure to PLA-8187 Page 4 of 4 3.2 Conclusion In conclusion, based on the considerations discussed above, (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.
- 4.
Environmental Consideration Susquehanna has determined that the proposed amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. However, the proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or a significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure.
Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.
of PLA-8187 Proposed Technical Specification Changes (Mark-Up)
Revised Technical Specifications Pages Unit 1 TS Pages 3.8-16 Unit 2 TS Pages 3.8-18
AC Sources - Operating 3.8.1 SUSQUEHANNA - UNIT 1 3.8-16 Amendment 178, 266, 269, xxx 3.8 Electrical Power Systems SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE FREQUENCY SR 3.8.1.20 Not Used------------------------------NOTES-------------------------
- 1. All DG starts may be preceded by an engine prelube period.
Verify, when started simultaneously from standby condition, each DG achieves, in 10 seconds, voltage 3793 V and frequency 58.8 and after steady state conditions are reached, maintains voltage 4000 V and 4400 V and frequency 59.3 Hz and 60.5 Hz.
In accordance with the Surveillance Frequency Control Program
AC Sources-Operating 3.8.1 SUSQUEHANNA - UNIT 2 3.8-18 Amendment 151, 247, 251, xxx SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE FREQUENCY SR 3.8.1.20 Not Used-------------------------------NOTES-----------------
- 1. All DG starts may be preceded by an engine prelube period.
Verify, when started simultaneously from standby condition, each DG achieves, in 10 seconds, voltage 3793 V and frequency 58.8 and after steady state conditions are reached, maintains voltage 4000 V and 4400 V and frequency 59.3 Hz and 60.5 Hz.
In accordance with the Surveillance Frequency Control Program SR 3.8.1.21 --------------------------NOTE------------------------------
When Unit 1 is in MODE 4 or 5, or moving irradiated fuel assemblies in the secondary containment, the Note to Unit 1 SR 3.8.2.1 is applicable.
For required Unit 1 AC sources, the following SRs of Unit 1 Specification 3.8.1 are applicable:
In accordance with applicable SRs SR 3.8.1.1; SR 3.8.1.10; SR 3.8.1.3; SR 3.8.1.11; SR 3.8.1.4; SR 3.8.1.14; SR 3.8.1.5; SR 3.8.1.15; SR 3.8.1.6; SR 3.8.1.16; SR 3.8.1.7; SR 3.8.1.18; SR 3.8.1.9; SR 3.8.1.19; and SR 3.8.1.8 (when more than one Unit 1 offsite circuit is required)
of PLA-8187 Revised Technical Specification Pages Revised Technical Specifications Pages Unit 1 TS Pages 3.8 -16 Unit 2 TS Pages 3.8-18
AC Sources - Operating 3.8.1 SUSQUEHANNA - UNIT 1 3.8-16 Amendment 178, 266, 269, xxx 3.8 Electrical Power Systems SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE FREQUENCY SR 3.8.1.20 Not Used
AC Sources-Operating 3.8.1 SUSQUEHANNA - UNIT 2 3.8-18 Amendment 151, 247, 251, xxx SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE FREQUENCY SR 3.8.1.20 Not Used SR 3.8.1.21 --------------------------NOTE------------------------------
When Unit 1 is in MODE 4 or 5, or moving irradiated fuel assemblies in the secondary containment, the Note to Unit 1 SR 3.8.2.1 is applicable.
For required Unit 1 AC sources, the following SRs of Unit 1 Specification 3.8.1 are applicable:
In accordance with applicable SRs SR 3.8.1.1; SR 3.8.1.10; SR 3.8.1.3; SR 3.8.1.11; SR 3.8.1.4; SR 3.8.1.14; SR 3.8.1.5; SR 3.8.1.15; SR 3.8.1.6; SR 3.8.1.16; SR 3.8.1.7; SR 3.8.1.18; SR 3.8.1.9; SR 3.8.1.19; and SR 3.8.1.8 (when more than one Unit 1 offsite circuit is required)
of PLA-8187 Proposed Technical Specification Bases Changes (Mark-Up) - For Information Only Revised Technical Specification Bases Pages Unit 1 TS Bases Pages 3.8-31, 42 Unit 2 TS Bases Pages 3.8-16, 32, 33, 43, 44
AC Sources - Operating B 3.8.1 SUSQUEHANNA - UNIT 1 3.8-31 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.8.1.19 (continued)
The reason for Note 3 is that performing the Surveillance would remove a required offsite circuit from service, perturb the electrical distribution system, and challenge safety systems. This Surveillance tests the applicable logic associated with Unit 1. The comparable test specified in the Unit 2 Technical Specifications tests the applicable logic associated with Unit 2. Consequently, a test must be performed within the specified Frequency for each unit. As the Surveillance represents separate tests, the Note specifying the restriction for not performing the test while the unit is in MODE 1, 2 or 3 does not have applicability to Unit 2. The Note only applies to Unit 1, thus the Unit 1 Surveillances shall not be performed with Unit 1 in MODE 1, 2 or 3.
SR 3.8.1.20 Not UsedThis Surveillance demonstrates that the DG starting independence has not been compromised. Also, this Surveillance demonstrates that each engine can achieve proper speed within the specified time when the DGs are started simultaneously. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.
This SR is modified by two Notes. The reason for Note 1 is to minimize wear on the DG during testing. The Note allows all DG starts to be preceded by an engine prelube period (which for DGs A through D includes operation of the lube oil system to ensure the DG's turbo charger is sufficiently prelubricated). For the purpose of this testing, the DGs must be started from standby conditions, that is, with the engine oil continuously circulated and engine coolant being circulated as necessary to maintain temperature consistent with manufacturer recommendations.
Note 2 is necessary to identify that this test does not have to be performed with DG E substituted for any DG. The allowance is acceptable based on the design of the DG E transfer switches. The transfer of control, protection, indication, and alarms is by switches at two separate locations.
These switches provide a double break between DG E and the redundant system within the transfer switch panel. The transfer of power is through circuit breakers at two separate locations for each redundant system.
There are four normally empty switch gear positions at DG E facility, associated with each of the four existing DGs. Only one circuit breaker is available at this location to be inserted into one of the four positions. At each of the existing DGs, there are two switchgear positions with only one circuit breaker available. This design provides two open circuits between redundant power sources. Therefore, based on the described design, it can be concluded that DG redundancy and independence is maintained regardless of whether DG E is substituted for any other DG.
AC Sources-Shutdown B 3.8.2 SUSQUEHANNA - UNIT 1 3.8-42 BASES ACTIONS (continued)
A.2.1, and A.2.2, and A.2.3 (continued)
Condition A to provide requirements for the loss of the offsite circuit whether or not a 4.16 kV ESS bus is de-energized. LCO 3.8.8 provides the appropriate restrictions for the situation involving a de-energized 4.16 kV ESS bus.
SURVEILLANCE REQUIREMENTS SR 3.8.2.1 SR 3.8.2.1 requires the SRs from LCO 3.8.1 that are necessary for ensuring the OPERABILITY of the AC sources in other than MODES 1, 2, and 3. SR 3.8.1.8 is not required to be met since only one offsite circuit is required to be OPERABLE. SR 3.8.1.7, SR 3.8.1.11, SR 3.8.1.12, SR 3.8.1.13, SR 3.8.1.15, SR 3.8.1.18, and SR 3.8.1.19 are not required to be met because DG start and load within a specified time and response on an offsite power or ECCS initiation signal is not required.
SR 3.8.1.17 is not required to be met because the required OPERABLE DG(s) is not required to undergo periods of being synchronized to the offsite circuit. SR 3.8.1.20 is excepted because starting independence is not required with the DGs that are not required to be OPERABLE. Refer to the corresponding Bases for LCO 3.8.1 for a discussion of each SR.
This SR is modified by a Note that specified SRs must be met but are not required to be performed. The reason for the Note is to preclude requiring the OPERABLE DG(s) from being paralleled with the offsite power network or otherwise rendered inoperable during the performance of SRs, and to preclude de-energizing a required 4.16 kV ESS bus or disconnecting a required offsite circuit during performance of SRs. With limited AC sources available, a single event could compromise both the required circuit and the DG.
It is the intent that these SRs must still be capable of being met, but actual performance is not required during periods when the DG and offsite circuit is required to be OPERABLE.
REFERENCES
- 1.
Final Policy Statement on Technical Specifications Improvements, July 22, 1993 (58 FR 39132).
AC Sources - Operating B 3.8.1 SUSQUEHANNA - UNIT 2 3.8-16 BASES SURVEILLANCE REQUIREMENTS (continued)
Unit 2 by LCO 3.8.7, Distribution Systems-Operating. As Noted at the beginning of the SRs, SR 3.8.1.1 through SR 3.8.1.2019 are applicable to the Unit 2 AC sources and SR 3.8.1.21 is applicable to the Unit 1 AC sources.
Where the SRs discussed herein specify voltage and frequency tolerances, the following summary is applicable. The minimum steady state output voltage of 4000 V represents the value that will allow the degraded voltage relays to reset after actuation. This value is based on the upper value of the degraded voltage relay reset voltage of 3938 V, representing 94.68% of 4160 V, plus the worst-case voltage drop from the DG to an associated 4.16 kV switchgear bus. The specified maximum steady state output voltage of 4400 V is equal to the maximum operating voltage specified for 4000 V. It ensures that for a lightly loaded distribution system, the voltage at the terminals of 4000 V motors is no more than the maximum rated operating voltages.
The minimum frequency value is derived from the recommendations found in Regulatory Guide 1.9 (Ref. 3). The allowable steady state frequency for all DGs is 60 Hz +/-2%. DG E is also required to maintain a frequency of not less than 57 Hz during transient conditions.
To provide additional margin for DG E to meet the 57 Hz criteria, the 2% margin allowed for steady state frequency is further reduced to 1%, or 0.6 Hz. This value, added to the tolerance allowed for the DGs electronic governor (0.1Hz) provides the 59.3 Hz minimum frequency value applicable for all DGs.
The maximum frequency is derived from analysis based on an iterative approach using voltage and frequency variations of the DG to determine the maximum continuous loading on the DG such that the DG loading does not exceed its continuous rating and still performs its design function.
Through a qualitative estimation and a dynamic transient simulation, the maximum frequency meeting the iterative approach is 60.5 Hz.
The Surveillance Table has been modified by a Note, to clarify the testing requirements associated with DG E. The Note is necessary to define the intent of the Surveillance Requirements associated with the integration of DG E. Specifically, the Note defines that a DG is only considered OPERABLE and required when it is aligned to the Class 1E distribution system. For example, if DG A does not meet the requirements of a specific SR, but DG E is substituted for DG A and aligned to the Class 1E distribution system, DG E is required to be OPERABLE to satisfy the LCO requirement of 4 DGs and DG A is not required to be OPERABLE because it is not aligned to the Class 1E distribution system. This is acceptable because only 4 DGs are assumed in the event analysis.
AC Sources - Operating B 3.8.1 SUSQUEHANNA - UNIT 2 3.8-32 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.8.1.20 Not UsedThis Surveillance demonstrates that the DG starting independence has not been compromised. Also, this Surveillance demonstrates that each engine can achieve proper speed within the specified time when the DGs are started simultaneously. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.
This SR is modified by two Notes. The reason for Note 1 is to minimize wear on the DG during testing. The Note allows all DG starts to be preceded by an engine prelube period (which for DGs A through D includes operation of the lube oil system to ensure the DG's turbo charger is sufficiently prelubricated.) For the purpose of this testing, the DG's must be started from standby conditions, that is, with the engine oil continuously circulated and engine coolant being circulated as necessary to maintain temperature consistent with manufacturer recommendations.
Note 2 is necessary to identify that this test does not have to be performed with DG E substituted for any DG. The allowance is acceptable based on the design of the DG E transfer switches. The transfer of control, protection, indication, and alarms is by switches at two separate locations.
These switches provide a double break between DG E and the redundant system within the transfer switch panel. The transfer of power is through circuit breakers at two separate locations for each redundant system.
There are four normally empty switchgear positions at DG E facility, associated with each of the four existing DGs. Only one circuit breaker is available at this location to be inserted into one of the four positions. At each of the existing DGs, there are two switchgear positions with only one circuit breaker available. This design provides two open circuits between redundant power sources. Therefore, based on the described design, it can be concluded that DG redundancy and independence is maintained regardless of whether DG E is substituted for any other DG.
AC Sources - Operating B 3.8.1 SUSQUEHANNA - UNIT 2 3.8-33 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.8.1.21 This Surveillance is provided to direct that the appropriate Surveillances for Unit 1 AC sources required to support Unit 2 are governed by the Unit 2 Technical Specifications. With the exception of this Surveillance, all other Surveillances of this Specification (SR 3.8.1.1 through SR 3.8.1.1920) are applicable to the Unit 2 AC sources only. Meeting the SR requirements of Unit 1 LCO 3.8.1 will satisfy all Unit 2 requirements for Unit 1 AC sources.
However, sixfive Unit 1 LCO 3.8.1 SRs, if not required to support Unit 1 OPERABILITY requirements, are not required when demonstrating Unit 1 sources are capable of supporting Unit 2. SR 3.8.1.8 is not required if only one Unit 1 offsite circuit is required by the Unit 2 Specification.
SR 3.8.1.12, SR 3.8.1.13, SR 3.8.1.17, and SR 3.8.1.19 are not required since these SRs test the Unit 2 ECCS initiation signal, which is not needed for the AC sources to be OPERABLE on Unit 2. SR 3.8.1.20 is not required since starting independence is not required with the DG(s) not required to be OPERABLE.
The Frequency required by the applicable Unit 1 SR also governs performance of that SR for Unit 2.
As Noted, if Unit 1 is in MODE 4 or 5, the Note to Unit 1 SR 3.8.2.1 is applicable. This ensures that a Unit 2 SR will not require a Unit 1 SR to be performed, when the Unit 1 Technical Specifications do not require performance of a Unit 1 SR. (However, as stated in the Unit 2 SR 3.8.2.1 Note, while performance of an SR is not required, the SR still must be met).
AC Source-Shutdown B 3.8.2 SUSQUEHANNA - UNIT 2 3.8-43 BASES ACTIONS (continued)
A.2.1, and A.2.2, and A.2.3 (continued)
Because of the allowance provided by LCO 3.0.6, the Distribution System ACTIONS would not be entered even if all AC sources to it are inoperable, resulting in de-energization. Therefore, the Required Actions of Condition A have been modified by a Note to indicate that when Condition A is entered with no AC power to any required ESS bus, ACTIONS for LCO 3.8.8 must be immediately entered. This Note allows Condition A to provide requirements for the loss of the offsite circuit whether or not a 4.16 kV ESS bus is de-energized. LCO 3.8.8 provides the appropriate restrictions for the situation involving a de-energized 4.16 kV ESS bus.
SURVEILLANCE REQUIREMENTS SR 3.8.2.1 SR 3.8.2.1 requires the SRs from LCO 3.8.1 that are necessary for ensuring the OPERABILITY of the AC sources in other than MODES 1, 2, and 3. SR 3.8.1.8 is not required to be met since only one offsite circuit is required to be OPERABLE. SR 3.8.1.7, SR 3.8.1.11, SR 3.8.1.12, SR 3.8.1.13, SR 3.8.1.15, SR 3.8.1.18, and SR 3.8.1.19 are not required to be met because DG start and load within a specified time and response on an offsite power or ECCS initiation signal is not required.
SR 3.8.1.17 is not required to be met because the required OPERABLE DG(s) is not required to undergo periods of being synchronized to the offsite circuit. SR 3.8.1.20 is excepted because starting independence is not required with the DGs that are not required to be OPERABLE. Refer to the corresponding Bases for LCO 3.8.1 for a discussion of each SR.
This SR is modified by a Note that specified SRs must be met but are not required to be performed. The reason for the Note is to preclude requiring the OPERABLE DG(s) from being paralleled with the offsite power network or otherwise rendered inoperable during the performance of SRs, and to preclude de-energizing a required 4160 V ESS bus or disconnecting a required offsite circuit during performance of SRs. With limited AC sources available, a single event could compromise both the required circuit and the DG.
It is the intent that these SRs must still be capable of being met, but actual performance is not required during periods when the DG and offsite circuit is required to be OPERABLE.
AC Source-Shutdown B 3.8.2 SUSQUEHANNA - UNIT 2 3.8-44 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.8.2.2 This Surveillance is provided to direct that the appropriate Surveillances for Unit 1 AC sources required to support Unit 2 are governed by the Unit 2 Technical Specifications. With the exception of this Surveillance, all other Surveillances of this Specification (SR 3.8.1.1 through SR 3.8.1.2019) are applicable to the Unit 2 AC sources only. Meeting the SR requirements of Unit 1 LCO 3.8.1 will satisfy all Unit 2 requirements for Unit 1 AC sources.
However, tennine Unit 1 LCO 3.8.1 SRs, if not required to support Unit 1 OPERABILITY requirements, are not required when demonstrating Unit 1 sources are capable of supporting Unit 2. SR 3.8.1.8 is not required if only one Unit 1 offsite circuit is required by the Unit 2 Specification. SR 3.8.1.7, SR 3.8.1.11, SR 3.8.1.12, SR 3.8.1.13, SR 3.8.1.15, SR 3.8.1.17, SR 3.8.1.18 and SR 3.8.1.19 are not required to be met because DG start and load within a specified time and response on an offsite power or ECCS initiation signal is not required for the AC sources to be OPERABLE on Unit 2. SR 3.8.1.20 is not required since starting independence is not required with the DG(s) not required to be OPERABLE.
The Frequency required by the applicable Unit 1 SR also governs performance of that SR for Unit 2.
As Noted, if Unit 1 is in MODE 4 or 5, the Note to Unit 1 SR 3.8.2.1 is applicable. This ensures that a Unit 2 SR will not require a Unit 1 SR to be performed, when the Unit 1 Technical Specifications do not require performance of a Unit 1 SR. (However, as stated in the Unit 2 SR 3.8.2.1 Note, while performance of an SR is not required, the SR still must be met).
REFERENCES
- 1.
Final Policy Statement on Technical Specifications Improvements, July 22, 1993 (58 FR 39132).