Text

Temporary Change to the Technical Specifications to Allow Replacement of Transformers 1X230 and 1X240 PLA-7892
	ML20310A231
Person / Time
Site:	Susquehanna
Issue date:	11/05/2020
From:	Cimorelli K; Susquehanna, Talen Energy
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
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ML20310A230	List: PLA-7892, Temporary Change to the Technical Specifications to Allow Replacement of Transformers 1X230 and 1X240 PLA-7892;
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ENCLOSURE 5 CONTAINS SECURITY-RELATED INFORMATION WITHHOLD UNDER 10 CFR 2.390 Kevin Cimorelli Susquehanna Nuclear, LLC Site Vice President 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.3795 Fax 570.542.1504 Kevin.Cimorelli@TalenEnergy.com November 5, 2020 Attn: Document Control Desk 10 CFR 50.90 U. S. Nuclear Regulatory Commission Washington, DC 20555-0001 SUSQUEHANNA STEAM ELECTRIC STATION PROPOSED AMENDMENT TO LICENSE NPF-22:

TEMPORARY CHANGE TO THE TECHNICAL SPECIFICATIONS TO ALLOW REPLACEMENT OF UNIT 1 TRANSFORMERS 1X230 AND 1X240 PLA-7892 Docket No. 50-388

References:

1. Susquehanna letter to NRC, Proposed Amendment Number 292 to Unit 2 Operating License No. NPF-22: Temporary Change to Allow Replacement of the Unit 1 480 V ESS Load Center Transformers in Unit 2 Technical Specifications 3.8.7 and 3.7.1 (PLA-7384), dated January 28, 2016 (ADAMS Accession No. ML16029A031).

2. NRC letter to Susquehanna, Issuance of Amendment Re: Temporary Change of Technical Specifications to Allow Replacement of Engineered Safeguard System Load Center Transformers (CAC No. MF7298), dated January 26, 2017 (ADAMS Accession No. ML17004A250).

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), Unit 2, Facility Operating License number NPF-22. The proposed amendment would modify TS 3.8.7, Distribution Systems - Operating.

In Reference 1, Susquehanna requested a temporary extension to Completion Times in TS 3.7.1, Residual Heat Removal Service Water (RHRSW) System and the Ultimate Heat Sink (UHS),

and TS 3.8.7 from 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months to 7 days. The extension was necessary to support replacement of Unit 1 Engineered Safeguard System Transformers 1X210, 1X220, 1X230, and 1X240. The SSES design is such that these Unit 1 transformers provide power to equipment required for

Document Control Desk PLA-7892 operation of Unit 2, thereby necessitating either a dual unit shutdown to replace the transformers or an extension to the Completion Times for Unit 2 to accommodate replacement during a planned Unit 1 refueling outage. The NRC approved a Completion Time extension for Unit 2 in Reference 2. The extension was temporary and expired on June 15, 2020.

At the time of the application submitted in Reference 1, Susquehanna intended to replace two transformers during the Unit 1 refueling outages in 2018 (1X220 and 1X240) and the other two in 2020 (1X210 and 1X230). However, based on scheduling and resource limitations, Susquehanna determined it was necessary to split the transformer replacements across four refueling outages rather than two. Thus, Transformer 1X240 was not replaced during the 2018 refueling outage and 1X230 was not replaced during the 2020 refueling outage as originally planned. Susquehanna intends to replace Transformer 1X240 during the Unit 1 2022 refueling outage and Transformer 1X230 during the Unit 1 2024 refueling outage. As such, Susquehanna is requesting the temporary Completion Time extension for TS 3.8.7 approved in Reference 2 be extended to expire on June 15, 2024, and revised to limit its applicability to only replacement of Transformers 1X230 and 1X240. The Completion Time extension for TS 3.7.1 was only required for replacement of Transformers 1X210 and 1X220, both of which have already been replaced. Therefore, this request will be limited to only the extended Completion Time in TS 3.8.7 as approved in Reference 2. provides a description and assessment of the proposed changes along with Susquehanna's determination that the proposed changes do not involve a significant hazard consideration. Enclosure 2 provides the existing TS pages marked to show the proposed changes. Enclosure 3 provides revised (clean) TS pages. Enclosure 4 provides the existing TS Bases pages marked up to show the proposed changes and is provided for information only. provides applicable plant drawings to aid in the NRCs review and is provided for information only. The drawings provided in Enclosure 5 are considered sensitive, unclassified, non-safeguards information and are requested to be withheld from public disclosure in accordance with 10 CFR 2.390(d)(1).

Susquehanna requests NRC approval of the proposed changes and issuance of the requested license amendment by November 30, 2021. 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 enclosures, to the designated Commonwealth of Pennsylvania state official.

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.

Document Control Desk PLA-7892 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 pe1jury that the foregoing is true and correct.

Executed on:

Enclosures:

1. Description and Assessment

2. Marked-Up Technical Specification Pages

3. Revised (Clean) Technical Specification Pages

4. Marked-Up Technical Specification Bases Pages (Provided for Information Only)

5. Applicable Plant Drawings (Provided for Information Only) [SECURITY-RELATED INFORMATION - WITHHOLD FROM PUBLIC DISCLOSURE]

Copy: NRC Region I Mr. C. Highley, NRC Senior Resident Inspector Ms. S. Goetz, NRC Project Manager Mr. M. Shields, PA DEP/BRP (w/out Enclosure 5)

Enclosure 1 to PLA-7892 Description and Assessment

1.

SUMMARY

DESCRIPTION

2. DETAILED DESCRIPTION 2.1 System Design and Operation 2.2 Current Technical Specifications Requirements 2.3 Reason for the Proposed Change 2.4 Description of the Proposed Change

3. TECHNICAL EVALUATION 3.1 Work Evolution 3.2 Impacts to Other Systems

4. REGULATORY EVALUATION 4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedent 4.3 No Significant Hazards Consideration Analysis 4.4 Conclusions

5. ENVIRONMENTAL CONSIDERATION

6. REFERENCES

Enclosure 1 to PLA-7892 Page 1 of 24 SUSQUEHANNA ASSESSMENT

1. Summary Description 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), Unit 2, Facility Operating License number NPF-22. The proposed amendment would modify TS 3.8.7, Distribution Systems - Operating.

In Reference 1, Susquehanna requested a temporary extension to Completion Times in TS 3.7.1, Residual Heat Removal Service Water (RHRSW) System and the Ultimate Heat Sink (UHS),

and TS 3.8.7 from 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months to 7 days. The extension was necessary to support replacement of Unit 1 Engineered Safeguard System (ESS) Transformers 1X210, 1X220, 1X230, and 1X240.

The SSES design is such that these Unit 1 transformers provide power to equipment required for operation of Unit 2, thereby necessitating either a dual unit shutdown to replace the transformers or an extension to the Completion Times for Unit 2 to accommodate replacement during a planned Unit 1 refueling outage. The NRC approved a Completion Time extension for Unit 2 in Reference 2. The extension was temporary and expired on June 15, 2020.

At the time of the application submitted in Reference 1, Susquehanna intended to replace two transformers during the Unit 1 refueling outages in 2018 (1X220 and 1X240) and the other two in 2020 (1X210 and 1X230). However, based on scheduling and resource limitations, Susquehanna determined it was necessary to split the transformer replacements across four refueling outages rather than two. Thus, Transformer 1X240 was not replaced during the 2018 refueling outage and 1X230 was not replaced during the 2020 refueling outage as originally planned. Susquehanna intends to replace Transformer 1X240 during the Unit 1 2022 refueling outage and Transformer 1X230 during the Unit 1 2024 refueling outage. Therefore, Susquehanna is requesting the temporary Completion Time extension approved in Reference 2 be extended to expire on June 15, 2024, and revised to limit its applicability to only replacement of Transformers 1X230 and 1X240. The Completion Time extension for TS 3.7.1 was only required for replacement of Transformers 1X210 and 1X220, both of which have already been replaced. Therefore, this request will be limited to only the extended Completion Time in TS 3.8.7 as approved in Reference 2.

2. Detailed Description 2.1 System Design and Operation As described in Sections 8.2 and 8.3 of the Updated Final Safety Analysis Report (FSAR), the SSES Alternating Current (AC) Distribution System transmits the output of the Unit 1 and

Enclosure 1 to PLA-7892 Page 2 of 24 Unit 2 Main Generators to offsite switchyards and distributes power from the unit auxiliary and offsite power supplies to onsite AC loads. These loads are required for startup, normal unit operation, shutdown, and emergency plant operations. Voltage levels of 500 kV, 230 kV, 24 kV, 13.8 kV, 4.16 kV, 480 V and 208/120 V are provided for a variety of reasons.

The electric power distribution system includes Class 1E and non-Class 1E AC Power Systems. to Reference 3 provided detailed drawings to aid the NRCs review. Enclosure 5 to this letter provides the current revisions of the applicable drawings previously provided for information only (Note: the drawings pertaining strictly to Transformers 1X210 and 1X220 and Load Centers (LCs) 1B210 and 1B220 are not provided in Enclosure 5). The non-Class 1E portion of the onsite power system provides AC power for non-safety related loads. A limited number of non-safety related loads are important to the power generating equipment integrity and are fed from the Class 1E Distribution System. The non-Class 1E AC Power System distributes power at 13.8 kV, 4.16 kV, 480 V, and 208/120 V, grouped into two symmetrical distribution systems stemming from 13.8 kV buses.

The Class 1E AC Power System distributes power at 4.16 kV, 480 V, and 208/120 V to safety-related loads. The Class 1E AC System is divided into four load group channels per unit (Channels A, B, C, and D). Any three out of four load groups have the capability of supplying the minimum required safety loads. The 4.16 kV bus of each Class 1E load group channel is provided with connections to two offsite power sources designated as the preferred and alternate power supplies (preferred and alternate power supplies up to the 4.16 kV buses of the Class 1E Power System are considered non-Class 1E). Five diesel generators (DGs) are available to provide the required power supply if a total loss of the preferred and alternate supplies occurs.

Four DGs shared between the two units provide emergency power for one of the four Class 1E AC load groups in each Unit when normal sources are lost. Two divisionalized load groups are established from the four Class 1E AC load groups (Division 1 is comprised of Channels A and C; Division 2 is comprised of Channels B and D) for those engineered safety feature loads which require one out of two load groups to meet design basis requirements. A spare DG (the E DG) can be manually aligned as a replacement for any of the other four DGs.

The ESS buses designated load group channels for Unit 1 and 2 are displayed in Table 1. Each ESS bus powers a 4.16 kV/ 480 V ESS LC transformer used to supply an essential 480 V single-ended LC. The associated 4.16 kV ESS bus is the only source of power to the respected LC through the LC transformer.

The ESS LC supplies power to the individual 480 V loads and to Motor Control Centers (MCCs) that power instrument AC distribution panels, 125 VDC Battery Chargers, and essential plant lighting. The 250 VDC Battery Chargers on each unit are supplied by that units 4.16 kV ESS bus. The 125 VDC Battery Charger can be supplied from either units 480 V LC via an Automatic Transfer Switch (ATS). The Unit 2 and common loads ultimately powered from

Enclosure 1 to PLA-7892 Page 3 of 24 Transformer 1X230 are listed in Table 3; the Transformer 1X240 loads are listed in Table 4.

Tables 3 and 4 also list the impacts on TS Limiting Conditions for Operations (LCOs) and Technical Requirement Manual (TRM) Technical Requirements for Operation (TROs) for de-energizations of the listed components.

Table 1 - 4.16 kV / 480 V AC Distribution System Components 4.16 kV Load Connecting 480 V ESS Bus Group Transformer Load Center 1A201 A 1X210 1B210 1A203 C 1X230 1B230 1A202 B 1X220 1B220 1A204 D 1X240 1B240 2A201 A 2X210 2B210 2A203 C 2X230 2B230 2A202 B 2X220 2B220 2A204 D 2X240 2B240 2.2 Current Technical Specifications Requirements LCO 3.8.7 requires the electrical distribution subsystems listed in Table 3.8.7-1 to be operable in Modes 1, 2, and 3. Table 3.8.7-1 lists 480 V LCs 1B230 and 1B240 as required Unit 1 distribution systems to support Unit 2 operation. In the event that one Unit 1 electrical power distribution subsystem is inoperable, Required Action C.1 requires the inoperable distribution subsystem be restored to operable status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or 7 days during replacement of 480 V ESS Load Center Transformers in Unit 1. The 7-day Completion Time is modified by a footnote which indicates the Completion Time is temporary and expired on June 15, 2020. If the distribution subsystem cannot be restored to operable status, Required Actions E.1 and E.2 direct entry into Mode 3 within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and Mode 4 within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months , respectively. LCO 3.8.7 is not applicable in Mode 4 or 5.

2.3 Reason for the Proposed Change Transformers 1X230 and 1X240 are approaching the end of their intended service life. In order to ensure continued reliable operation of the SSES units, Susquehanna is proactively replacing the transformers. As described in Reference 1, removing Transformer 1X230 or 1X240 from service with Unit 1 in Mode 4 or 5 and Unit 2 not in Mode 4 or 5 requires entry into Condition C of LCO 3.8.7 on Unit 2. The associated Completion Time of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months is insufficient to allow

Enclosure 1 to PLA-7892 Page 4 of 24 for the approximate 108 hours0.00125 days 0.03 hours 1.785714e-4 weeks 4.1094e-5 months required to replace a transformer. As such, it is not possible to replace one of the transformers within the permanent 72 hour8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months Completion Time.

At the time of its initial application in Reference 1, Susquehanna intended to replace two transformers during each Unit 1 refueling outage in 2018 and 2020. As such, the temporary Completion Time extension was believed to only be necessary through June 15, 2020.

Subsequent to the NRCs approval of the amendment in Reference 2, Susquehanna determined it was prudent to replace only one transformer per refueling outage, replacing 1X220 in 2018 and 1X210 in 2020. Transformers 1X230 and 1X240 still require replacement to support continued reliable operation of the SSES units, and are scheduled for replacement in 2024 and 2022, respectively. The temporary Completion Time has expired per the footnote and needs to be extended to 2024 to support the future transformer replacements.

2.4 Description of the Proposed Change The footnote modifying the 7-day Completion Time for LCO 3.8.7, Required Action C.1, is revised to state that the temporary Completion Time expires on June 15, 2024. The footnote is further revised to clarify that the temporary Completion Time is limited to only the replacement of Transformers 1X230 and 1X240. The proposed TS page is provided in Enclosures 2 and 3.

Conforming changes are made to the TS Bases, and are provided in Enclosure 4 for information only.

3. Technical Evaluation This section discusses the proposed changes in context with the plant configuration in which the changes will apply. Specifically, the changes are only applicable when Unit 1 is in Mode 4 or 5 and Unit 2 is in Mode 1, 2, or 3. Additionally, the extended Completion Time is only applicable during the replacement of 1X230 and 1X240.

It should be noted that Transformers 1X230 and 1X240 do not provide power to any components in the RHRSW System. Extension of the Completion Times for Required Actions A.3 and B.1 of LCO 3.7.1 was required in Reference 1 due to the replacements of Transformers 1X210 and 1X220. Because those replacements are complete, it is no longer necessary to apply extended Completion Times to the Actions in LCO 3.7.1. As such, all requirements pertaining to the RHRSW System are no longer applicable and information regarding RHRSW System limitations is not reproduced in this license amendment request.

3.1 Work Evolution 3.1.1 Pre-Work Tasks Prior to commencing work to replace the transformers, the following will be performed:

Enclosure 1 to PLA-7892 Page 5 of 24

Equipment will be verified to be operable prior to commencement of the replacement evolution.

o SSES has 4 DGs that are connected to the Class 1E distribution system to meet LCO 3.8.1. The DGs are tested monthly to ensure the ability to start from standby condition and achieve rated parameters within their required start times per Surveillance Requirement (SR) 3.8.1.3 and SR 3.8.1.7. Additionally, SR 3.8.1.14 ensure the DGs are capable of providing emergency power for the full duration of which they are required. Because the DGs are shared between Units 1 and 2 and Unit 2 will be in Modes 1, 2, or 3, the DGs will be required to operable throughout the evolution.

o Prior to transformer replacement, SR 3.8.1.19 will be performed on Unit 1 for the same division in the maintenance window. This assures that response of the other bus in that division and the DG, including safety related loads and load timers, are all operable and performing as designed.

A Loss of Safety Function Analysis will be performed for any system to which LCO 3.0.6 has been applied. This analysis will ensure the ability to perform a safety function assumed in the accident analyses is preserved.

3.1.2 Replacement Evolution Work schedules developed by experienced schedulers were drafted using typical/historical values for a 480 V ESS LC transformer replacement evolution. The schedules require the following basic steps:

1. De-energize the transformer and associated LC

2. Remove enclosure panels and transformer accessories (prepare for rigging)

3. De-terminate primary, secondary, and grounding of original transformer

4. Rig out original transformer

5. Rig in replacement transformer

6. Weld and bolt replacement transformer

7. Perform pre-connection megger and doble testing of replacement transformer to verify no damage during installation

Enclosure 1 to PLA-7892 Page 6 of 24

8. Terminate primary, secondary, and side windings of replacement transformer

9. Perform pre-energization megger and doble testing of replacement transformer

10. Energize replacement transformer and validate phase rotation on secondary side of transformer (requires restoration of the 4.16 kV bus)

11. Perform additional post maintenance tests (PMTs)

12. Reinstall enclosure panels and accessories

13. Restore associated LC and perform post-modification testing The draft schedules show that 108 hours0.00125 days 0.03 hours 1.785714e-4 weeks 4.1094e-5 months of work is required strictly to replace the transformers.

This includes time to perform all work that cannot be performed outside the Completion Time window, such as:

Clearance order application;

Pre-evolution testing and maintenance;

Engineering review of test results that may influence the scope or schedule of work to be performed;

The replacement itself;

Work that supports the replacement evolution such as scaffold, rigging, and welding; and

Post-evolution testing and maintenance.

The schedule considers human factors such as shift turnover and fatigue rule restrictions, further making the estimate realistic. The schedule does not consider any contingent replacements that may occur. This could include replacement of the surge arrestors, cables, and various components. The risk of unanticipated outcomes weighed against Completion Times is a primary driver in such planning evolutions. The anticipated duration of 108 hours0.00125 days 0.03 hours 1.785714e-4 weeks 4.1094e-5 months is approximately 65 percent of the requested time (i.e., 168 hours0.00194 days 0.0467 hours 2.777778e-4 weeks 6.3924e-5 months ). This will accommodate unexpected responses or maintenance that may result during the transformer replacement.

Enclosure 1 to PLA-7892 Page 7 of 24 3.1.3 Additional Considerations Regardless of which transformer is being replaced, the following items remain constant throughout the replacement evolution:

All four Unit 2 4.16 kV ESS Buses remain energized and operable.

All four common DGs remain operable.

All 125 VDC and 250 VDC Battery Chargers, Batteries, and Distribution Systems for Unit 2 remain operable.

Operation of the Unit 2 Emergency Core Cooling Systems is unaffected by the transformer replacements.

If severe weather is forecasted, operators will take actions required by existing station procedures for responding to severe weather. Such actions could include termination of non-essential or operational risk significant activities. Further, severe weather conditions are inputs to the standard work management processes.

Emergent plant conditions will be addressed in accordance with the applicable station processes including work management and maintenance rule guidelines.

Equipment will be protected and discretionary maintenance controlled in accordance with procedure NDAP-QA-0340, Protected Equipment Program. Susquehanna will evaluate the transformer replacement and protect equipment in accordance with the program at the time of the evolution. Currently, the list of protected equipment would include:

o Offsite Power Sources o Opposite division of Shutdown Cooling (if in service) o Opposite division DGs o Opposite division of Core Spray System o Opposite division of Standby Gas Treatment (SGT) System o Opposite division of Control Room Emergency Outside Air Supply (CREOAS)

System

Enclosure 1 to PLA-7892 Page 8 of 24 o Opposite division Control Structure Chiller o Opposite division Unit 1 Emergency Switchgear Cooling 3.2 Impacts to Other Systems After review of Tables 3 and 4, it can be demonstrated that the TS impacts associated with the replacement of Transformers 1X230 and 1X240 are limited to those displayed in Table 2. A discussion of each of the impacted TS-related systems follows, as well as discussions of the fire protection system and Unit 2 AC and DC instrumentation system implications.

Table 2 - TS Impacts of Transformer 1X230 and 1X240 Replacements Transformer Equipment Impacted Associated Unit 2 Associated TS Completion Time 1X230 SGT System, Division 1 3.6.4.3 7 days CREOAS System, Division 1 3.7.3 7 days Control Room Floor Cooling 3.7.4 30 days System, Division 1 1X240 SGT System, Division 2 3.6.4.3 7 days CREOAS System, Division 2 3.7.3 7 days Control Room Floor Cooling 3.7.4 30 days System, Division 2 Standby Gas Treatment System The SGT System is designed to ensure that radioactive materials that leak from the primary containment into the secondary containment following a Design Basis Accident (DBA) are filtered and adsorbed prior to exhausting to the environment. It is comprised of two independent, 100 percent capacity subsystems. Each subsystem contains an air fan, demister, heater, filters, charcoal adsorber, dampers and ductwork.

Transformer 1X230 provides power to components in Division 1 of the SGT System.

Transformer 1X240 provides power to components in Division 2 of the SGT System. In accordance with LCO 3.6.4.3, each SGT subsystem is required to be operable in Modes 1, 2, and 3, during movement of irradiated fuel assemblies in the secondary containment, and during Core Alterations. Non-functional power supplies would render the SGT System inoperable.

However, LCO 3.0.6 does not require entering the Conditions and performing the Required

Enclosure 1 to PLA-7892 Page 9 of 24 Actions of LCO 3.6.4.3 so long as the inoperable transformer is the only reason that the SGT System is inoperable. Thus, the TS would not require performance of the Required Actions when SGT was inoperable during the replacement of the transformers. Therefore, the transformer replacement evolution will have no TS impacts on the SGT System.

During the evolution to replace the transformers, only one transformer will be replaced during each refueling outage; i.e., the other transformer will be operable and capable of providing power to the other SGT subsystem. Thus, the required filtration would still be able to be performed by the other SGT subsystem in the event of an accident on Unit 2 during transformer replacement. Further, LCO 3.6.4.3 allows one division of the SGT System to be inoperable for up to 7 days, the period of time to which the transformer replacement is limited. In the event the transformer replacement exceeds 7 days, the TS would require a shutdown of Unit 2; the same as required if a division of the SGT System were inoperable for greater than 7 days.

Control Room Emergency Outside Air Supply System The CREOAS System provides a protected environment from which occupants can control the unit following an uncontrolled release of radioactivity, hazardous chemicals, or smoke. It is comprised of two independent and redundant high efficiency air filtration subsystems for emergency treatment of outside supply air and a Control Room Envelope (CRE) boundary that limits the inleakage of unfiltered air. Each CREOAS subsystem consists of an electric heater, filters, charcoal adsorber, fans, and the associated ductwork, valves or dampers, doors, barriers, and instrumentation.

Transformer 1X230 provides power to components in Division 1 of the CREOAS System.

Transformer 1X240 provides power to components in Division 2 of the CREOAS System. In accordance with LCO 3.7.3, each CREOAS subsystem is required to be operable in Modes 1, 2, and 3, during movement of irradiated fuel assemblies in the secondary containment, and during Core Alterations. Non-functional power supplies would render the CREOAS System inoperable.

However, LCO 3.0.6 does not require entering the Conditions and performing the Required Actions of LCO 3.7.3 so long as the inoperable transformer is the only reason that the CREOAS System is inoperable. Thus, the TS would not require performance of the Required Actions when CREOAS was inoperable during the replacement of the transformers. Therefore, the transformer replacement evolution will have no TS impacts on the CREOAS System.

During the evolution to replace the transformers, only one transformer will be replaced during each refueling outage; i.e., the other transformer will be operable and capable of providing power to the other CREOAS subsystem. Thus, the required filtration would still be able to be performed by the other CREOAS subsystem in the event of an accident on Unit 2 during transformer replacement. Further, LCO 3.7.3 allows one division of the CREOAS System to be inoperable for up to 7 days, the period of time to which the transformer replacement is limited.

In the event the transformer replacement exceeds 7 days, the TS would require a shutdown of

Enclosure 1 to PLA-7892 Page 10 of 24 Unit 2; the same as required if a division of the CREOAS System were inoperable for greater than 7 days.

Control Room Floor Cooling System The Control Room Floor Cooling System provides temperature control for the control room and pressure control for the control room habitability envelope. It is comprised of two independent, redundant systems that provide cooling of recirculated control room air. Each subsystem consists of cooling coils, fans, chillers, compressors, ductwork, dampers, and instrumentation and controls to provide for temperature control.

Transformer 1X230 provides power to components in Division 1 of the Control Room Floor Cooling System. Transformer 1X240 provides power to components in Division 2 of the Control Room Floor Cooling System. In accordance with LCO 3.7.4, each Control Room Floor Cooling subsystem is required to be operable in Modes 1, 2, and 3, during movement of irradiated fuel assemblies in the secondary containment, and during Core Alterations. Non-functional power supplies would render the Control Room Floor Cooling System inoperable.

However, LCO 3.0.6 does not require entering the Conditions and performing the Required Actions of LCO 3.7.4 so long as the inoperable transformer is the only reason that the Control Room Floor Cooling System is inoperable. Thus, the TS would not require performance of the Required Actions when the Control Room Floor Cooling System was inoperable during the replacement of the transformers. Therefore, the transformer replacement evolution will have no TS impacts on the Control Room Floor Cooling System.

During the evolution to replace the transformers, only one transformer will be replaced during each refueling outage; i.e., the other transformer will be operable and capable of providing power to the other Control Room Floor Cooling subsystem. Thus, the required cooling and pressurization of the CRHE would still be able to be performed by the other Control Room Floor Cooling subsystem in the event of an accident on Unit 2 during transformer replacement.

Further, LCO 3.7.4 allows one division of the Control Room Floor Cooling System to be inoperable for up to 30 days, which is greater than the period of time to which the transformer replacement is limited. In the event the transformer replacement exceeds 7 days, the TS would require a shutdown of Unit 2; a more conservative action than required if a division of the Control Room Floor Cooling System were inoperable for greater than 7 days.

Fire Protection Systems The Enclosure to Reference 1 identified that the Emergency Service Water (ESW), RHRSW, SGT, CREOAS, and Control Room Floor Cooling Systems are the shared systems required to function during a unit shut down in response to a fire. However, the proposed change in Reference 1 did not result in impacting the ability of the SGT, CREOAS, and Control Room Floor Cooling Systems to perform their required post fire safe shutdown functions. That remains

Enclosure 1 to PLA-7892 Page 11 of 24 true in this requested amendment. Further, the impacts to the ESW and RHRSW Systems identified in Reference 1 are not applicable to this requested change. The impacts stemmed from the fact that Transformers 1X210 and 1X220 provided power to RHRSW System components in the flow path to the UHS. Because those transformers have already been replaced and will not be taken out of service to replace Transformers 1X230 and 1X240, there are no impacts on the ESW and RHRSW Systems ability to perform their post fire safe shutdown functions. As such, the proposed change does not result in any impacts to the fire protection systems at SSES.

Unit 2 and Common Electrical Loads The impacted Unit 2 AC and DC power system loads are the Unit 2, 125 VDC Battery Chargers 2D633 and 2D643. Battery Charger 2D633 is powered from MCC 0B536; 2D643 is powered from MCC 0B546. Impacted common electrical system loads include the DG components that are also powered from MCCs 0B536 and 0B546, as displayed in Tables 3 and 4, respectively.

MCC 0B536 is typically powered from LC 1B230, but can be aligned to LC 2B230 via Automatic Transfer Switch (ATS) 0-ATS-536. Similarly, MCC 0B546 is typically powered from LC 1B240 but can be aligned to LC 2B240 via 0-ATS-546. During the Transformer replacement evolution, MCCs 0B536 and 0B546 will be fed from their alternate sources via the appropriate ATS. Therefore, all Unit 2 and common DC loads will continue to be fed from Class 1E power sources and will continue to permit functioning of structures, systems, and components important to safety during transformer replacement.

4. Regulatory Evaluation 4.1 Applicable Regulatory Requirements/Criteria Title 10 Code of Federal Regulations (10 CFR) 50.36(c)(2)

Limiting Conditions for operation are the lowest functional capability or performance levels of equipment required for safe operation of the facility. When a limiting condition for operation of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial actions permitted by the technical specifications until the condition can be met.

Conclusion 10 CFR 50.36 sets the regulatory requirements for the content of TS as quoted above.

10 CFR 50.36(c)(2) requires, in part, that the TS contain LCOs, and that remedial actions are prescribed for when a nuclear power plant fails to meet an LCO. The proposed change would increase the time allotted to perform remedial actions, which is not specified by the regulation.

Therefore, 10 CFR 50.36(c)(2) will continue to be met.

Enclosure 1 to PLA-7892 Page 12 of 24 General Design Criteria During the applicable period of this proposed license amendment, SSES will maintain the ability to meet the applicable General Design Criteria (GDC) as described in FSAR Section 3.1.

GDC-5, Sharing of Structures, Systems, and Components 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.

GDC-17, Electric Power Systems An onsite electric power system and an offsite electric power system shall be provided to permit functioning of structures, systems, and components important to safety. The safety function for each system (assuming the other system is not functioning) shall be to provide sufficient capacity and capability to assure that (1) specified acceptable fuel design limits and design conditions of the reactor coolant pressure boundary are not exceeded as a result of anticipated operational occurrences and (2) the core is cooled and containment integrity and other vital functions are maintained in the event of postulated accidents.

The onsite electric power supplies, including the batteries, and the onsite electric distribution system, shall have sufficient independence, redundancy, and testability to perform their safety functions assuming a single failure.

Electric power from the transmission network to the onsite electric distribution system shall be supplied by two physically independent circuits (not necessarily on separate rights of way) 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. A switchyard common to both circuits is acceptable. Each of these circuits shall be designed to be available in sufficient time following a loss of all onsite alternating current power supplies and the other offsite electric power circuit, to assure that specified acceptable fuel design limits and design conditions of the reactor coolant pressure boundary are not exceeded. One of these circuits shall be designed to be available within a few seconds following a loss-of-coolant accident to assure that core cooling, containment integrity, and other vital safety functions are maintained.

Provisions shall be included to minimize the probability of losing electric power from any of the remaining supplies as a result of, or coincident with, the loss of power

Enclosure 1 to PLA-7892 Page 13 of 24 generated by the nuclear power unit, the loss of power from the transmission network, or the loss of power from the onsite electric power supplies.

Conclusion The proposed change to the TS will not permanently impact any installed components at SSES; the replacement transformers have been demonstrated to provide the same functionality as the original transformers. During the transformer replacement activities, one division of the SGT, CREOAS, and Control Room Floor Cooling Systems will not be capable of performing their safety function. However, the other division of the systems will remain operable throughout the transformer replacement evolution as well as both divisions of the Emergency Core Cooling Systems, RHRSW System, the ESW System, and the UHS. One division of SGT, CREOAS, and the Control Room Floor Cooling Systems are capable of providing the required fission product filtration and control room cooling required in the event of an accident during transformer replacement. Therefore, the criteria above and as listed in the SSES FSAR continue to be met.

4.2 Precedent The NRC previously approved, in Reference 2, Susquehannas original license amendment request to support transformer replacement on the anticipated timeframe at the time of submittal.

Subsequently, Susquehanna has replaced two of the four transformers, leaving 1X230 and 1X240 for the 2024 and 2022 Unit 1 refueling outages, respectively. This application provides all the information related to replacement of transformers 1X230 and 1X240 previously provided in References 1, 3, and 4. This application does not reproduce the information in References 1, 3, and 4 only pertaining to the replacement of transformers 1X210 and 1X220; those transformer replacements have already been completed and extension of the temporary Completion Time to support their replacement in TS 3.7.1 is not required.

Similarly, in Reference 5, the NRC approved an extension to a previously issued temporary Completion Time extension to Duke Energy for the McGuire Nuclear Station. The McGuire Nuclear Station is a Pressurized Water Reactor and the primary and secondary systems differ from those at SSES accordingly. Additionally, the amendment was issued to support replacement of piping in a service water system as opposed to replacement of an electrical transformer. However, the approval does apply in this instance in that Duke had a previously approved temporary Completion Time extension (Reference 6), changed the schedule for replacement following the NRCs initial approval, and was granted additional time to perform the replacement.

Enclosure 1 to PLA-7892 Page 14 of 24 4.3 No Significant Hazards Considerations Analysis In accordance with the requirements of 10 CFR 50.90, Susquehanna Nuclear, LLC (Susquehanna), requests an amendment to the Technical Specifications (TS) for the Susquehanna Steam Electric Station (SSES), Unit 2. The proposed amendment would modify TS 3.8.7, Distribution Systems - Operating. Specifically, the proposed amendment would revise the footnote modifying the 7-day Completion Time of Required Action C.1 to indicate it expires in 2024 rather than 2020 and also to limit its applicability to replacement of 480 V Emergency Safeguard System (ESS) transformers 1X230 and 1X240 on Unit 1.

Susquehanna has evaluated the proposed amendment against the standards in 10 CFR 50.92 and has determined that the operation of the SSES in accordance with the proposed amendment presents no significant hazards. Susquehannas evaluation against each of the criteria in 10 CFR 50.92 follows.

1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No The proposed change is to extend the applicability of a previously approved temporary extension to existing TS Completion Times to allow for ESS transformer replacements. The opposite division electrical distribution systems from which the ESS transformer replacement is occurring will remain operable during the temporary 7-day Completion Time.

The replacement transformers have been evaluated and confirmed to provide the same level of functionality as the original transformers, and will provide for more reliable operations due to the difference in age. Further, the proposed change does not alter accident analysis assumptions, add any initiators, or affect the function of plant systems or the manner in which systems are operated, maintained, tested, or inspected. The proposed change does not require any plant modifications which affect the performance capability of the structures, systems, and components relied upon to mitigate the consequences of postulated accidents.

Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No The proposed change is to extend the applicability of a previously approved temporary extension to existing TS Completion Times to allow for ESS transformer replacements. The

Enclosure 1 to PLA-7892 Page 15 of 24 proposed change does not impact the accident analysis. The proposed change does result in new transformers being installed, however they will not be operated in a new or different manner. The proposed change does not introduce failure modes that could result in a new accident, and the change does not alter assumptions made in the safety analysis. The proposed change does not alter or prevent the ability of the operators to perform their intended functions to mitigate the consequences of an accident or event.

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 change involve a significant reduction in a margin of safety?

Response: No The proposed change is to extend the applicability of a previously approved temporary extension to existing TS Completion Times to allow for ESS transformer replacements. The proposed change does not alter the manner in which safety limits, limiting safety settings, or limiting conditions for operation are determined. The safety analysis assumptions and acceptance criteria are not affected by this change. The change will ultimately result in an increase in a margin of safety due to installation of new transformers.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above evaluation, Susquehanna concludes that the proposed amendment does not involve a 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.

4.4 Conclusions 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.

5. 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

Enclosure 1 to PLA-7892 Page 16 of 24 change in the types or 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.

6. References

1. Susquehanna letter to NRC, Proposed Amendment Number 292 to Unit 2 Operating License No. NPF-22: Temporary Change to Allow Replacement of the Unit 1 480 V ESS Load Center Transformers in Unit 2 Technical Specifications 3.8.7 and 3.7.1 (PLA-7384), dated January 28, 2016 (ADAMS Accession No. ML16029A031).

2. NRC letter to Susquehanna, Issuance of Amendment Re: Temporary Change of Technical Specifications to Allow Replacement of Engineered Safeguard System Load Center Transformers (CAC No. MF7298), dated January 26, 2017 (ADAMS Accession No. ML17004A250).

3. Susquehanna letter to NRC, Supplemental Information for License Amendment Request Extending Completion Times in Support of 480V ESS Load Center Transformer Replacements (PLA-7451), dated April 6, 2016 (ADAMS Accession No. ML16097A486).

4. Susquehanna letter to NRC, Response to Request for Additional Information Re:

License Amendment Request Extending Completion Times in Support of 480V ESS Load Center Transformer Replacements (PLA-7537), dated October 10, 2016 (ADAMS Accession No. ML16284A013).

5. NRC letter to Duke Energy, Issuance of Amendments 308 and 287 for Temporary Changes to Technical Specifications to Address an A Train Nuclear Service Water Non-Conforming Condition (CAC Nos. MG242 and MG0243; EPID L-2017-LLA-0299), dated February 15, 2018 (ADAMS Accession No. ML18030A682).

6. NRC letter to Duke Energy, Issuance of License Amendment Regarding Nuclear Service Water System Allowed Outage Time Extension (CAC Nos. MF6409 and MF6410), dated March 16, 2016 (ADAMS Accession No. ML15306A141).

Enclosure 1 to PLA-7892 Page 17 of 24 Table 3 - 1X230 Unit 2 and Common Loads Affected by De-Energization Power Source Component # Component Description Applicable Applicable Unit 2 Completion LCO/TRO Time LC 1B230 0E145A Control Structure A/C Unit A Heater TRO 3.7.9 30 days MCC 0B136 0V109A Fan LCO 3.6.4.3 7 days 0C886A Control Panel LCO 3.6.4.3 7 days 0V118A Room Exchange Fan TRO 3.7.9 30 days 0V144A Equipment Room Fan TRO 3.7.9 30 days 0E144A Equipment Room Heating Coil TRO 3.7.9 30 days 0V101A CREOAS System Fan LCO 3.7.3 7 days 0P171A Chilled Water System (CWS) Emergency Condenser LCO 3.7.3 7 days Water Pump LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0P162A Chilled Water Pump LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0P122A Chiller 0K112A Oil Pump LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days

Enclosure 1 to PLA-7892 Page 18 of 24 Table 3 - 1X230 Unit 2 and Common Loads Affected by De-Energization Power Source Component # Component Description Applicable Applicable Unit 2 Completion LCO/TRO Time MCC 0B136 0K115A Pumpout compressor for Chiller 0K112A None NA (continued) 0E143A Control Room Emergency Fresh Air Heating Coil LCO 3.7.3 7 days 0V103A Heating & Ventilation (H&V) System Fan LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0V117A Control Room Ceiling Fan LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0V115A Computer Room Ceiling Fan LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0V116A Battery Room Exhaust Fan TRO 3.7.9 30 days MCC 0B536 (1) 0P514C DG C Fuel Oil Transfer Pump None NA HV01110C DC C ESW Loop B Supply Isolation Valve None NA 0P531C DG C Motor Driven Standby Jacket Water Pump None NA HV01122C DG C ESW Loop A Return Isolation Valve None NA

Enclosure 1 to PLA-7892 Page 19 of 24 Table 3 - 1X230 Unit 2 and Common Loads Affected by De-Energization Power Source Component # Component Description Applicable Applicable Unit 2 Completion LCO/TRO Time MCC 0B536 0P533C (1)

DG C Motor Driven Lube Oil Pump None NA (continued)

HV01120C DG C ESW Loop B Return Isolation Valve None NA HV01112C DG C ESW Loop A Supply Isolation Valve None NA 0P532C DG C Motor Driven Pre-lube Pump None NA 0X509 DG 480/120 V Transformer C None NA 0C577C DG HVAC Panel None NA 0E525C DG C Lube Oil Heater None NA 0E508C DG C Jacket Water Immersion Heater None NA 0V512C DG Building Vent Fan Supply Fan None NA 0E570C DG Space Heater C None NA 2D633 Unit 2 125 VDC Battery Charger 0B536071 None NA 0P530C DG C Jacket Water Circ Pump None NA MCC 1B236 HV08601A(2) Emergency Switchgear Unit Cooler A Control Structure None NA Chilled Water Outlet Valve

Enclosure 1 to PLA-7892 Page 20 of 24 Table 3 - 1X230 Unit 2 and Common Loads Affected by De-Energization Power Source Component # Component Description Applicable Applicable Unit 2 Completion LCO/TRO Time 1Y236 Various 120 VAC instrument power to instrumentation for various LCO 3.6.4.3 7 days systems and control power to dampers, including the LCO 3.3.7.1 7 days(3) systems described above. LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days NOTES (1) Prior to commencement of the transformer replacement, MCC 0B536 will be transferred to LC 2B230 as described in Section 3.2. Thus, the loads off of MCC 0B536 will remain energized throughout the evolution and there are no TS impacts to those components.

(2) Electrically disabled (3) Completion Time is based on LCO 3.7.3. Required Actions for LCO 3.3.7.1 can require declaring CREOAS System inoperable, thereby making the LCO 3.7.3 Required Actions and Completion Times applicable after the short delay period allotted in the LCO 3.3.7.1 Required Actions. Completion Time is listed as 7 days for simplicity.

Enclosure 1 to PLA-7892 Page 21 of 24 Table 4 - 1X240 Unit 2 and Common Loads Affected by De-Energization Power Source Component # Component Description Applicable Applicable Unit 2 Completion LCO/TRO Time LC 1B240 0E145B Control Structure A/C Unit B Heater TRO 3.7.9 30 days MCC 0B146 0V109B Fan LCO 3.6.4.3 7 days 0C886B Control Panel LCO 3.6.4.3 7 days 0V118B Room Exchange Fan TRO 3.7.9 30 days 0V144B Equipment Room Fan TRO 3.7.9 30 days 0E144B Equipment Room Heating Coil TRO 3.7.9 30 days 0V101B CREOAS System Fan LCO 3.7.3 7 days 0P171B CWS Emergency Condenser Water Pump LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0P162B Chilled Water Pump LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0P122B Chiller 0K112B Oil Pump LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days

Enclosure 1 to PLA-7892 Page 22 of 24 Table 4 - 1X240 Unit 2 and Common Loads Affected by De-Energization Power Source Component # Component Description Applicable Applicable Unit 2 Completion LCO/TRO Time MCC 0B146 0K115B Pumpout compressor for Chiller 0K112B None NA (continued) 0E143B Control Room Emergency Fresh Air Heating Coil LCO 3.7.3 7 days 0V103B H&V System Fan LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0V117B Control Room Ceiling Fan LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0V115B Computer Room Ceiling Fan LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days 0V116B Battery Room Exhaust Fan TRO 3.7.9 30 days MCC 0B546 (1) 0P514D DG D Fuel Oil Transfer Pump None NA HV01110D DG D ESW Loop B Supply Isolation Valve None NA 0P531D DG D Motor Driven Standby Jacket Water Pump None NA HV01122D DG D ESW Loop A Return Isolation Valve None NA

Enclosure 1 to PLA-7892 Page 23 of 24 Table 4 - 1X240 Unit 2 and Common Loads Affected by De-Energization Power Source Component # Component Description Applicable Applicable Unit 2 Completion LCO/TRO Time MCC 0B546 0P533D (1)

DG D Motor Driven Lube Oil Pump None NA (continued)

HV01120D DG D ESW Loop B Return Isolation Valve None NA HV01112D DG D ESW Loop A Supply Isolation Valve None NA 0P532D DG D Motor Driven Pre-lube Pump None NA 0X510 DG 480/120 V Transformer D None NA 0C577D DG HVAC Panel None NA 0E525D DG D Lube Oil Heater None NA 0E508D DG D Jacket Water Immersion Heater None NA 0V512D DG Building Vent Fan Supply Fan None NA 0E570D DG Space Heater D None NA 2D643 Unit 2 125 VDC Battery Charger 0B546071 None NA 0P530D DG D Jacket Water Circ Pump None NA MCC 1B246 HV08603B(2) Emergency Switchgear Unit Cooler B Control Structure None NA Chilled Water Inlet Valve HV08602B(2) Emergency Switchgear Unit Cooler B Control Structure None NA Chilled Water Bypass Valve

Enclosure 1 to PLA-7892 Page 24 of 24 Table 4 - 1X240 Unit 2 and Common Loads Affected by De-Energization Power Source Component # Component Description Applicable Applicable Unit 2 Completion LCO/TRO Time 1Y246 Various 120 VAC instrument power to instrumentation for various LCO 3.6.4.3 7 days systems and control power to dampers, including the LCO 3.3.7.1 7 days(3) systems described above. LCO 3.7.3 7 days LCO 3.7.4 30 days TRO 3.7.9 30 days TRO 3.8.6 30 days NOTES (1) Prior to commencement of the transformer replacement, MCC 0B546 will be transferred to LC 2B240 as described in Section 3.2. Thus, the loads off of MCC 0B546 will remain energized throughout the evolution and there are no TS impacts to those components.

(2) Electrically disabled (3) Completion Time is based on LCO 3.7.3. Required Actions for LCO 3.3.7.1 can require declaring CREOAS System inoperable, thereby making the LCO 3.7.3 Required Actions and Completion Times applicable after the short delay period allotted in the LCO 3.3.7.1 Required Actions. Completion Time is listed as 7 days for simplicity.

Enclosure 2 of PLA-7892 Marked-Up Technical Specification Pages Revised Technical Specifications Pages Unit 2 TS Page 3.8-45

Distribution Systems - Operating 3.8.7 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C. One Unit 1 AC electrical C.1 Restore Unit 1 AC electrical 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months power distribution power distribution subsystem inoperable. subsystem to OPERABLE OR status.

7 days during the replacement of 480 V ESS Load Center Transformers in Unit 1(1)

D. Two Unit 1 AC electrical D.1 Restore at least one Unit 1 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months power distribution AC electrical power subsystems on one distribution subsystems to Division inoperable for OPERABLE status.

performance of Unit 1 SR 3.8.1.19.

E. Required Action and E.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months Associated Completion Time of Condition A, B, or AND C not met.

E.2 Be in MODE 4. 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months F. Diesel Generator E DC F.1 Verify that all ESW valves 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months electrical power associated with Diesel subsystem inoperable, Generator E are closed.

while not aligned to the Class 1E distribution system.

G. Diesel Generator E DC G.1 Declare Diesel Generator E 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months electrical power inoperable.

subsystem inoperable, while aligned to the Class 1E distribution system.

(1) This temporary 7-day completion time is applicable during the replacement of all Unit 1 480 V ESS Load Center Transformers 1X230 and 1X240, while Unit 1 is in MODES 4 or 5, and will expire on June 15, 20202024.

SUSQUEHANNA - UNIT 2 3.8-45 Amendment 151, 208, 255, XXX

Enclosure 3 of PLA-7892 Revised (Clean) Technical Specification Pages Revised Technical Specifications Pages Unit 2 TS Page 3.8-45

Distribution Systems - Operating 3.8.7 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C. One Unit 1 AC electrical C.1 Restore Unit 1 AC electrical 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months power distribution power distribution subsystem inoperable. subsystem to OPERABLE OR status.

7 days during the replacement of 480 V ESS Load Center Transformers in Unit 1(1)

D. Two Unit 1 AC electrical D.1 Restore at least one Unit 1 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months power distribution AC electrical power subsystems on one distribution subsystems to Division inoperable for OPERABLE status.

performance of Unit 1 SR 3.8.1.19.

E. Required Action and E.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months Associated Completion Time of Condition A, B, or AND C not met.

E.2 Be in MODE 4. 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months F. Diesel Generator E DC F.1 Verify that all ESW valves 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months electrical power associated with Diesel subsystem inoperable, Generator E are closed.

while not aligned to the Class 1E distribution system.

G. Diesel Generator E DC G.1 Declare Diesel Generator E 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months electrical power inoperable.

subsystem inoperable, while aligned to the Class 1E distribution system.

(1) This temporary 7-day completion time is applicable during the replacement of Unit 1 480 V ESS Load Center Transformers 1X230 and 1X240, while Unit 1 is in MODES 4 or 5, and will expire on June 15, 2024.

SUSQUEHANNA - UNIT 2 3.8-45 Amendment 151, 208, 255, XXX

Enclosure 4 of PLA-7892 Marked-Up Technical Specification Bases Pages Revised Technical Specification Bases Pages Unit 2 TS Bases Page 3.8-89 (Provided for Information Only)

Rev. 7 Distribution Systems-Operating B 3.8.7 BASES ACTIONS C.1 (continued)

(continued)

The Completion Time has been extended to 7 days in order to complete the replacement of the four (4) Unit 1 480 V ESS Load Center Transformers 1X230 and 1X240. This is a temporary extension of the Completion Time. Upon completion of the transformer replacement, this temporary extension is no longer applicable and will expire on June 15, 20202024.

D.1 With two required Unit 1 AC buses, load centers, motor control centers, or distribution panels inoperable for the performance of Unit 1 SR 3.8.1.19 but not resulting in a loss of safety function, the remaining AC electrical power distribution subsystems are capable of supporting the minimum safety functions necessary to shut down the reactor and maintain it in a safe shutdown condition, assuming no single failure. The overall reliability is reduced, however, because a single failure in the remaining power distribution subsystems could result in the minimum required ESF functions not being supported. Therefore, the required AC buses, load centers, motor control centers, and distribution panels must be restored to OPERABLE status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

E.1and E.2 If the inoperable distribution subsystem cannot be restored to OPERABLE status within the associated Completion Time, the unit must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and to MODE 4 within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months . The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

F.1 If Diesel Generator E is not aligned to the Class 1E distribution system, the only supported safety function is for the ESW system. Therefore, under this condition, if Diesel Generator E DC power distribution subsystem is not OPERABLE, to ensure the OPERABILITY of the ESW system, actions are taken to either restore the power distribution subsystem to OPERABLE status or shutdown Diesel Generator E and close the associated ESW valves. The 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months limit is consistent with the allowed time for other inoperable DC power distribution subsystems and provides sufficient time to evaluate the condition and take the corrective actions.

SUSQUEHANNA - UNIT 2 3.8-89

v t e Letter Sequence Request
EPID:L-2020-LLA-0245, Temporary Change to the Technical Specifications to Allow Replacement of Transformers 1X230 and 1X240 PLA-7892 (Approved, Closed)
Initiation Request Acceptance... Administration Questions Answers Results Approval Other: ML21190A170
MONTHYEAR2021-11-04 [Table View]

PLA-7892, Temporary Change to the Technical Specifications to Allow Replacement of Transformers 1X230 and 1X240 PLA-7892

Text

References:

Enclosures:

SUMMARY

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