CNL-14-212, Expedited Seismic Evaluation Process Report (CEUS Sites) Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Re Recommendation 2.1 of the Near-Term Task Force Review of Insights from Fukushima Dai-ichi Accident

Expedited Seismic Evaluation Process Report (CEUS Sites) Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Re Recommendation 2.1 of the Near-Term Task Force Review of Insights from Fukushima Dai-ichi Accident

ML14365A072
Person / Time
Site:	Watts Bar
Issue date:	12/30/2014
From:	James Shea Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
CNL-14-212
Download: ML14365A072 (111)

Text

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-14-212 December 30, 2014 10 CFR 50.4 10 CFR 50.54(f)

Attn: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001



Watts Bar Nuclear Plant, Unit 1 Facility Operating License No. NPF-90 NRC Docket No. 50-390 Watts Bar Nuclear Plant, Unit 2 Construction Permit No. CPPR-92 NRC Docket No. 50-391

Subject:

Tennessee Valley Authoritys Watts Bar Nuclear Plant Expedited Seismic Evaluation Process Report (CEUS Sites) Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident

Reference:

NRC Letter, Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated March 12, 2012 (ML12056A046)

On March 12, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued the referenced letter to all power reactor licensees and holders of construction permits in active or deferred status. Enclosure 1 of the referenced letter requested each addressee located in the Central and Eastern United States (CEUS) to submit a Seismic Hazard Evaluation that includes an interim evaluation and actions taken or planned to address the higher seismic hazard relative to the design basis, as appropriate, prior to completion of the risk evaluation.

In accordance with the referenced letter above, TVA is enclosing the Expedited Seismic Evaluation Process (ESEP) Report for Watts Bar Nuclear Plant.

U.S. Nuclear Regulatory Commission CNL-14-212 Page 2 December 30, 2014 There are no new regulatory commitments resulting from this submittal. Should you have questions concerning the content of this letter, please contact Mr. Kevin Casey at (423) 751-8523.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 30th day of December 2014.

Respectfully, Digitally signed by J. W. Shea DN: cn=J. W. Shea, o=Tennessee J. W. Shea Valley Authority, ou=Nuclear Licensing, email=jwshea@tva.gov, c=US Date: 2014.12.30 11:50:55 -05'00' J. W. Shea Vice President, Nuclear Licensing

Enclosure:

Expedited Seismic Evaluation Process (ESEP) Report for Watts Bar Nuclear Plant cc (Enclosure):

NRR Director - NRC Headquarters NRO Director - NRC Headquarters NRR JLD Director - NRC Headquarters NRC Regional Administrator - Region II NRR Project Manager - Watts Bar Nuclear Plant, Unit 1 NRR Project Manager - Watts Bar Nuclear Plant, Unit 2 NRR JLD Project Manager - Watts Bar Nuclear Plant NRC Senior Resident Inspector - Watts Bar Nuclear Plant, Unit 1 NRC Senior Resident Inspector - Watts Bar Nuclear Plant, Unit 2

ENCLOSURE EXPEDITED SEISMIC EVALUATION PROCESS (ESEP) REPORT FOR WATTS BAR NUCLEAR PLANT

Watts Bar Nuclear Plant ESEP Report EXPEDITED SEISMIC EVALUATION PROCESS (ESEP) REPORT FOR WATTS BAR NUCLEAR PLANT

Watts Bar Nuclear Plant ESEP Report Table of Contents Page LIST OF TABLES ............................................................................................................................................ 4 LIST OF FIGURES .......................................................................................................................................... 5 1.0 PURPOSE AND OBJECTIVE ............................................................................................................... 6 2.0 BRIEF

SUMMARY

OF THE FLEX SEISMIC IMPLEMENTATION STRATEGIES ...................................... 6 3.0 EQUIPMENT SELECTION PROCESS AND ESEL.................................................................................. 8 3.1 Equipment Selection Process and ESEL .............................................................................. 8 3.1.1 ESEL Development ............................................................................................... 9 3.1.2 PowerOperated Valves ....................................................................................... 9 3.1.3 Pull Boxes ........................................................................................................... 10 3.1.4 Termination Cabinets......................................................................................... 10 3.1.5 Critical Instrumentation Indicators .................................................................... 10 3.1.6 Phase 2 and 3 Piping Connections ..................................................................... 10 3.2 Justification for Use of Equipment that is not the Primary Means for FLEX Implementation ................................................................................................................ 11 4.0 GROUND MOTION RESPONSE SPECTRUM (GMRS) ...................................................................... 11 4.1 Plot of GMRS Submitted by the Licensee ......................................................................... 11 4.2 Comparison to SSE ............................................................................................................ 13 5.0 REVIEW LEVEL GROUND MOTION (RLGM) ................................................................................... 14 5.1 Description of RLGM Selected .......................................................................................... 14 5.2 Method to Estimate InStructure Response Spectra (ISRS) .............................................. 15 6.0 SEISMIC MARGIN EVALUATION APPROACH ................................................................................. 16 6.1 Summary of Methodologies Used .................................................................................... 16 6.2 HCLPF Screening Process .................................................................................................. 17 6.3 Seismic Walkdown Approach ........................................................................................... 18 6.3.1 Walkdown Approach.......................................................................................... 18 6.3.2 Application of Previous Walkdown Information ............................................... 19 6.3.3 Significant Walkdown Findings .......................................................................... 19 6.4 HCLPF Calculation Process ................................................................................................ 20 6.5 Functional Evaluations of Relays ...................................................................................... 21 6.6 Tabulated ESEL HCLPF Values (Including Key Failure Modes) .......................................... 21 7.0 INACCESSIBLE ITEMS ..................................................................................................................... 21 7.1 Identification of ESEL items inaccessible for walkdowns ................................................. 21 7.2 Planned Walkdown / Evaluation Schedule / Close Out .................................................... 22 8.0 ESEP CONCLUSIONS AND RESULTS ............................................................................................... 22 8.1 Supporting Information .................................................................................................... 22

Watts Bar Nuclear Plant ESEP Report Table of Contents (continued)

Page 8.2 Identification of Planned Modifications ........................................................................... 23 8.3 Modification Implementation Schedule ........................................................................... 23 8.4 Summary of Regulatory Commitments ............................................................................ 24

9.0 REFERENCES

.................................................................................................................................. 25

Watts Bar Nuclear Plant ESEP Report List of Tables Page TABLE 41: GMRS FOR WATTS BAR NUCLEAR PLANT .............................................................................. 11 TABLE 42: SSE FOR WATTS BAR NUCLEAR PLANT .................................................................................. 13 TABLE 51: RLGM FOR WATTS BAR NUCLEAR PLANT .............................................................................. 14 TABLE A1: EXPEDITED SEISMIC EQUIPMENT LIST (ESEL) FOR SEQUOYAH NUCLEAR PLANT ................ A2 TABLE B1: ESEP HCLPF VALUES AND FAILURE MODES FOR WATTS BAR NUCLEAR PLANT .................. B2 Page 4

Watts Bar Nuclear Plant ESEP Report List of Figures Page FIGURE 41: GMRS FOR WATTS BAR NUCLEAR PLANT ............................................................................ 12 FIGURE 42: GMRS TO SSE COMPARISON FOR WATTS BAR NUCLEAR PLANT ........................................ 13 FIGURE 51: RLGM FOR WATTS BAR NUCLEAR PLANT ............................................................................ 15 FIGURE 52: NUREG/CR0098 (0.5) VERSUS WATTS BAR NUCLEAR PLANT SSE ...................................... 16 Page 5

Watts Bar Nuclear Plant ESEP Report 1.0 PURPOSE AND OBJECTIVE Following the accident at the Fukushima DaiIchi Nuclear Power Plant (NPP) resulting from the March 11, 2011, Great Tohoku Earthquake and subsequent tsunami, the Nuclear Regulatory Commission (NRC) established a NearTerm Task Force (NTTF) to conduct a systematic review of NRC processes and regulations and to determine if the agency should make additional improvements to its regulatory system. The NTTF developed a set of recommendations intended to clarify and strengthen the regulatory framework for protection against natural phenomena. Subsequently, the NRC issued a 50.54(f) letter on March 12, 2012 [1], requesting information to assure that these recommendations are addressed by all United States of America (U.S.) NPPs. The 50.54(f) letter requests that licensees and holders of construction permits under 10 CFR Part 50 reevaluate the seismic hazards at their sites against presentday United States NRC requirements and guidance. Depending on the comparison between the reevaluated seismic hazard and the current design basis, further risk assessment may be required. Risk assessment approaches acceptable to the staff include a Seismic Probabilistic Risk Assessment (SPRA), or a Seismic Margin assessment (SMA). Based upon the risk assessment results, the NRC staff will determine whether additional regulatory actions are necessary.

This Report describes the Expedited Seismic Evaluation Process (ESEP) undertaken for the Watts Bar NPP, Unit 1 and Unit 2 (WBNP). The intent of the ESEP is to perform an interim action in response to the NRCs 50.54(f) letter [1] to demonstrate Seismic Margin through a review of a subset of the plant equipment that can be relied upon to protect the Reactor Core following beyond design basis seismic events.

The ESEP is implemented using the methodologies in the NRC endorsed guidance in Electric Power Research Institute (EPRI) 3002000704, Seismic Evaluation Guidance: Augmented Approach for the Resolution of Fukushima NTTF Recommendation 2.1: Seismic [2].

The objective of this Report is to provide summary information describing the ESEP evaluations and results. The level of detail provided in the Report is intended to enable NRC to understand the inputs used, the evaluations performed, and the decisions made as a result of the interim evaluations.

2.0 BRIEF

SUMMARY

OF THE FLEX SEISMIC IMPLEMENTATION STRATEGIES The Watts Bar Nuclear Plant FLEX response strategies for Reactor Core Cooling and Heat Removal, Reactor Inventory Control/Longterm Subcriticality, and Containment Function are summarized below.

This summary is derived from the WBNP Overall Integrated Plan (OIP) in Response to the March 12, 2012, Commission Order EA12049 [3].

For At Power Conditions Core Cooling and Heat Removal Reactor core cooling and heat removal is achieved via steam release from the Steam Generators (SGs) with SG makeup from the Turbine Driven Auxiliary Feedwater Pump (TDAFWP) during FLEX Phase 1 with suction from the Auxiliary Feedwater Storage Tank. Local control and operation of the SG Atmospheric Relief Valves (ARVs) and the TDAFWP system is available and proceduralized so that operation from the main control room is not required.

To provide an unlimited supply of water for core cooling during Phase 2, portable LP FLEX Pumps will be staged at the Intake Pump Station (IPS) and take suction from the intake channel and discharge to Page 6

Watts Bar Nuclear Plant ESEP Report four emergency raw cooling water (ERCW) FLEX connections inside the IPS. They will be used to pressurize the ERCW headers which can then be used for direct supply to the TDAFWP suction.

When the TDAFWP becomes unavailable due to reduction in available steam pressure, a permanently installed IP FLEX pump will be used to continue to supply feedwater to the SGs. Suction would be from an ERCW FLEX connection on AB elevation (EL) 737 feet (ft). The discharge is routed by hose to the TDAFWP discharge FLEX connections on EL 729 ft in the South MSVV.

For Phase 3, WBNP will continue the Phase 2 coping strategies.

Reactor Inventory control For Phase 1, Reactor Coolant System (RCS) makeup will be provided by the cold leg accumulators. RCS depressurization and cool down will be initiated as soon as possible to reduce the Reactor Coolant Pump (RCP) seal leakage rate.

In Phase 2, RCS makeup will be provided by repowering existing Safety Injection (SI) pumps and using the pumps to inject borated water as needed into the RCS. The SI pumps will be repowered with a 3 MWe FLEX Diesel Generator. The SI pumps can be manually controlled with hand switches on Main Control Room Panel M6. The source of RCS makeup will be the Refueling Water Storage Tank (RWST).

Component Cooling System (CCS) pumps will be repowered using the 3 MWe FLEX diesel generators to provide cooling water to the SI pump oil cooler.

Later in Phase 2, when the RCS is depressurized sufficiently, a permanently installed HP FLEX pump will be used to inject borated water into the RCS through SI piping. These pumps would be aligned with a suction hose from RWST FLEX connections located on AB EL 692 ft and a discharge hose routed to a SIP discharge FLEX header connection on AB EL 692 ft. The HP FLEX Pumps are fed from and operated from the 480v C&A Vent Boards 1A22 and 2B22.

For Phase 3, WBNP will continue the Phase 2 coping strategies.

Containment Function There are no Phase 1 FLEX actions to maintain containment integrity. The primary Phase 2 FLEX strategy for containment integrity entails repowering one train of hydrogen igniters. For Phase 2, a Containment Air Return Fan inside of containment can be repowered.

For Phase 3, WBNP will continue the Phase 2 coping strategies.

Support Systems Key reactor parameters to be monitored during FLEX implementation are measured and indicated by instrumentation that is powered by the 125V DC vital battery. During Phase 1, the vital batteries provide power to needed instrumentation through the vital battery boards, vital inverters and vital instrument power boards.

During Phase 2, power to vital instrumentation will be maintained by supplying 480V AC power to the vital battery chargers through new, fused, FLEX distribution panels, which will be connected directly to the battery chargers. 480V AC power will be supplied to the distribution panels by prestaged, 480V AC FLEX diesel generators located on the roof of the Auxiliary Building.

During the early portions of Phase 2, the 6.9kV switchgear and 6.9kV Shutdown Boards will be energized with a prestaged 3 MWe FLEX diesel generator located in the FLEX building. This will allow reenergizing the SI pumps for inventory control.

Page 7

Watts Bar Nuclear Plant ESEP Report For Phase 3, WBNP will continue the Phase 2 coping strategies.

For Shutdown Conditions Reactor core cooling and heat removal with SGs not available is provided during Phase 1 by heating up and boiling of the RCS coolant inventory.

RCS inventory during Phase 1 may be maintained by gravity feed from the RWST at each unit. The ability of the RWST at each unit to provide a gravity feed to the RCS is limited by the RWST fluid height, line losses through the gravity feed path, and pressure within the RCS.

If it is determined that gravity feed is not effective to cool the RCS and prevent fuel damage, Watts Bar has taken actions to proceduralize administrative controls to prestage FLEX equipment prior to entering a condition where the SGs cannot provide adequate core cooling.

With SGs unavailable the transition to Phase 2 strategies will be required as inventory is lost from the RCS. Prior to loss of gravity feed from the RWST, the permanently installed 480v motor driven Mode 5

& 6 IP FLEX pump must be aligned to take suction from the RWST and deliver the coolant to the RCS via the Safety Injection System FLEX connections. Power supply and control are from the 480v C&A Vent Boards. Sufficient flushing flow will be needed to prevent boron precipitation.

Reactor core cooling with SGs not available is adequately maintained via the Phase 2 strategy.

For Phase 3, WBNP will continue the Phase 2 coping strategies.

WBNP will follow the guidance contained within the Nuclear Energy Institute (NEI) position paper dated September 18, 2013, entitled Position Paper: Shutdown/Refueling Modes (ADAMS No.

ML13273A514) [23].

3.0 EQUIPMENT SELECTION PROCESS AND ESEL The selection of equipment for the Expedited Seismic Equipment List (ESEL) followed the guidelines of EPRI 3002000704 [2]. The ESEL for Unit 1 and Unit 2 in presented in Attachments A. Information presented in Attachment A is drawn from [25].

3.1 Equipment Selection Process and ESEL The selection of equipment to be included on the ESEL was based on installed plant equipment credited in the FLEX strategies during Phase 1, 2, and 3 mitigation of a Beyond Design Basis External Event (BDBEE), as outlined in the WBNP OIP in Response to the March 12, 2012, Commission Order EA 12049 [3]. The OIP provides the WBNP FLEX mitigation strategy and serves as the basis for equipment selected for the ESEP.

The scope of installed plant equipment includes equipment relied upon for the FLEX strategies to sustain the critical functions of core cooling and containment integrity consistent with the Watts Bar OIP [3]. FLEX mitigation recovery actions are excluded from the ESEP scope per EPRI 3002000704 [2].

The overall list of planned FLEX modifications and the scope for consideration herein is limited to those required to support core cooling, reactor coolant inventory and subcriticality, and containment integrity functions. Portable and prestaged FLEX equipment (not permanently installed) are excluded from the ESEL per EPRI 3002000704.

The ESEL component selection follows the EPRI guidance outlined in Section 3.2 of EPRI 3002000704.

Page 8

Watts Bar Nuclear Plant ESEP Report

1. The scope of components is limited to that required to accomplish the core cooling and containment safety functions identified in Table 32 of EPRI 3002000704 [2]. The instrumentation monitoring requirements for core cooling/containment safety functions are limited to those outlined in the EPRI 3002000704 guidance, and are a subset of those outlined in the Watts Bar OIP [3].

2. The scope of components is limited to installed plant equipment and FLEX connections necessary to implement the Watts Bar, as described in Section 2.

3. The scope of components assumes the credited FLEX connection modifications are implemented, and are limited to those required to support a single FLEX success path (i.e.,

either Primary or Backup/Alternate).

4. The Primary FLEX success path is to be specified. Selection of the Backup/Alternate FLEX success path must be justified.

5. Phase 3 coping strategies are included in the ESEP scope, whereas recovery strategies are excluded.

6. Structures, systems, and components excluded per the EPRI 3002000704 guidance are:

Structures (e.g. containment, reactor building, control building, auxiliary building, etc.).

Piping, cabling, conduit, HVAC, and their supports.

Manual valves and rupture disks.

Poweroperated valves not required to change state as part of the FLEX mitigation strategies.

Nuclear steam supply system components (e.g. RPV and internals, reactor coolant pumps and seals, etc.).

7. For cases in which neither train was specified as a primary or backup strategy, then only one train component (generally A train) is included in the ESEL.

3.1.1 ESEL Development The ESEL was developed by reviewing the WBNP OIP [3] to determine the major equipment involved in the FLEX strategies. Further reviews of plant drawings (e.g., Process and Instrumentation Diagrams (P&IDs) and Electrical OneLine Diagrams) were performed to identify the boundaries of the flow paths to be used in the FLEX strategies and to identify specific components in the flow paths needed to support implementation of the FLEX strategies.

Boundaries were established at an electrical or mechanical isolation device (e.g., isolation amplifier, valve, etc.) in branch circuits/branch lines off the defined strategy electrical or fluid flowpath. P&IDs were the primary reference documents used to identify mechanical components and instrumentation.

The flow paths used for FLEX strategies were selected and specific components were identified using detailed equipment and instrument drawings, piping isometrics, electrical schematics and oneline drawings, system descriptions, design basis documents, etc., as necessary.

3.1.2 PowerOperated Valves Page 33 of EPRI 3002000704 [2] notes that power operated valves not required to change state as part of the FLEX mitigation strategies are excluded from the ESEL. Page 32 also notes that functional Page 9

Watts Bar Nuclear Plant ESEP Report failure modes of electrical and mechanical portions of the installed Phase 1 equipment should be considered (e.g. Auxiliary Feedwater (AFW) trips). To address this concern, the following guidance is applied in the Watts Bar ESEL for functional failure modes associated with power operated valves:

Power operated valves that remain energized during the ELAP events (such as DC powered valves), were included on the ESEL.

Power operated valves not required to change state as part of the FLEX mitigation strategies were not included on the ESEL. The seismic event also causes the ELAP event; therefore, the valves are incapable of spurious operation as they would be deenergized.

Power operated valves not required to change state as part of the FLEX mitigation strategies during Phase 1, and are reenergized and operated during subsequent Phase 2 and 3 strategies, were not evaluated for spurious valve operation as the seismic event that caused the ELAP has passed before the valves are repowered.

3.1.3 Pull Boxes Pull boxes were deemed unnecessary to add to the ESELs as these components provide completely passive locations for pulling or installing cables. No breaks or connections in the cabling are included in pull boxes. Pull boxes were considered part of conduit and cabling, which are excluded in accordance with EPRI 3002000704 [2].

3.1.4 Termination Cabinets Termination cabinets, including cabinets necessary for FLEX Phase 2 and 3 connections, provide consolidated locations for permanently connecting multiple cables. The termination cabinets and the internal connections provide a completely passive function; however, the cabinets are included in the ESEL to ensure industry knowledge on panel/anchorage failure vulnerabilities is addressed.

3.1.5 Critical Instrumentation Indicators Critical indicators and recorders are typically physically located on panels/cabinets and are included as separate components; however, seismic evaluation of the instrument indication may be included in the panel/cabinet seismic evaluation (ruleofthebox).

3.1.6 Phase 2 and 3 Piping Connections Item 2 in Section 3.1 above notes that the scope of equipment in the ESEL includes .FLEX connections necessary to implement the WBNP OIP [3] as described in section 2. Item 3 in Section 3.1 also notes that The scope of components assumes the credited FLEX connection modifications are implemented, and are limited to those required to support a single FLEX success path (i.e., either Primary or Backup/Alternate). Item 6 in Section 3.1 above goes on to explain that Piping, cabling, HVAC, and their supports are excluded from the ESEL scope in accordance with EPRI 3002000704 [2].

Therefore, piping and pipe supports associated with FLEX Phase 2 and Phase 3 connections are excluded from the scope of the ESEP evaluation. However, any active valves in FLEX Phase 2 and Phase 3 connection flow path are included in the ESEL.

Page 10

Watts Bar Nuclear Plant ESEP Report 3.2 Justification for Use of Equipment that is not the Primary Means for FLEX Implementation The WBNP ESEL is based on the primary means of implementing the FLEX strategy. Therefore, no additional justification is required.

4.0 GROUND MOTION RESPONSE SPECTRUM (GMRS) 4.1 Plot of GMRS Submitted by the Licensee The Safe Shutdown Earthquake (SSE) control point is defined at the reactor building (RB) foundation level at elevation 684 ft and is the deepest structure foundation control point. Table 41 shows the GMRS accelerations for a range of frequencies. The GMRS at the control point elevation is shown in Figure 41 [4].

Table 41 GMRS for Watts Bar Nuclear Plant Frequency (Hz) GMRS (g) 100 3.68E01 90 3.71E01 80 3.77E01 70 3.89E01 60 4.21E01 50 4.95E01 40 5.93E01 35 6.40E01 30 6.80E01 25 7.23E01 20 7.59E01 15 7.66E01 12.5 7.58E01 10 7.26E01 9 6.90E01 8 6.55E01 7 6.12E01 6 5.60E01 Page 11

Watts Bar Nuclear Plant ESEP Report Table 41 GMRS for Watts Bar Nuclear Plant (Continued)

Frequency (Hz) GMRS (g) 5 4.93E01 4 3.95E01 3.5 3.46E01 3 2.99E01 2.5 2.50E01 2 2.28E01 1.5 1.95E01 1.25 1.65E01 1 1.26E01 0.9 1.13E01 0.8 1.03E01 0.7 9.51E02 0.6 8.71E02 0.5 7.67E02 0.4 6.13E02 0.35 5.37E02 0.3 4.60E02 0.25 3.83E02 0.2 3.07E02 0.15 2.30E02 0.125 1.92E02 0.1 1.53E02 GMRS at Control point for Watts Bar Nuclear Plant, 5%

Damping 8.00E01 7.00E01 6.00E01 Acceleration (g) 5.00E01 4.00E01 3.00E01 2.00E01 1.00E01 0.00E+00 0.1 1 10 100 Frequency (Hz)

Figure 41: GMRS for Watts Bar Nuclear Plant Page 12

Watts Bar Nuclear Plant ESEP Report 4.2 Comparison to SSE The SSE was developed in accordance with 10 CFR Part 100 Appendix A through an evaluation of the maximum earthquake potential for the region surrounding the site. The SSE horizontal spectrum at the WBNP site derives from the maximum historic earthquake reported in the site province (the 1897 Giles County event) placed adjacent to the Site. The SSE response spectrum is characterized by a peak ground acceleration (PGA) of 0.18 acceleration of gravity (g) and a shape that conforms to a modified Newmark spectrum [6], which is similar to the Regulatory Guide (RG) 1.60 spectral shape. Figure 42 compares the GMRS to the SSE and illustrates that the GMRS exceeds the SSE in the frequency range above 4.5 Hertz (Hz). The maximum ratio of GMRS to SSE between 1 Hz and 10 Hz occurs at a frequency of 10 Hz and that ratio is approximately 2.0.

Table 42: SSE for Watts Bar Nuclear Plant 0.5 0.11 1 0.22 2 0.46 2.5 0.46 5 0.46 6.67 0.46 10 0.36 25 0.22 33 0.18 100 0.18 GMRS to SEE Comparison for Watts Bar Nuclear Plant, 5%

Damping 9.00E01 8.00E01 7.00E01 Acceleration (g) 6.00E01 5.00E01 4.00E01 Watts Bar GMRS 3.00E01 WBN SSE (0.18g) 2.00E01 1.00E01 0.00E+00 0.1 1 10 100 Frequency (Hz)

Figure 42: GMRS to SSE Comparison for Watts Bar Nuclear Plant Page 13

Watts Bar Nuclear Plant ESEP Report 5.0 REVIEW LEVEL GROUND MOTION (RLGM) 5.1 Description of RLGM Selected Section 4 of EPRI 3002000704 [2] presents two approaches for developing the RLGM to be used in the ESEP:

1. The RLGM may be derived by linearly scaling the SSE by the maximum ratio of the GMRS/SSE between the 1 and 10 Hz range (not to exceed 2x SSE). Instructure RLGM seismic motions would be derived using existing SSE based instructure response spectra (ISRS) with the same scale factor.

2. Alternately, licensees who have developed appropriate structural/soilstructure interaction (SSI) models capable of calculating ISRS based on site GMRS/uniform hazard response spectrum (UHRS) input may opt to use these ISRS in lieu of scaled SSE ISRS.

Based on a review of tabulated data in Table 41 and the SSE values in Table 42, in the range between 1 and 10 Hz the maximum ratio of GMRS to the SSE is calculated to be:

SFmax = SAGMRS(10 HZ)/SA SSE 10Hz) = 0.726g/0.36g = 2.02 Since the computed scale factor is greater than 2.0, the RLGM would be set a level of 2x SSE. This is shown in Table 51 and Figure 51.

Table 51 RLGM for Watts Bar Nuclear Plant 0.5 0.22 1 0.44 2 0.92 2.5 0.92 5 0.92 6.67 0.92 10 0.72 25 0.44 33 0.36 100 0.36 Page 14

Watts Bar Nuclear Plant ESEP Report RLGM for Watts Bar Nuclear Plant 1.00E+00 9.00E01 8.00E01 7.00E01 Acceleration (g) 6.00E01 5.00E01 Watts Bar GMRS 4.00E01 RLGM= 2x SSE 3.00E01 2.00E01 1.00E01 0.00E+00 0.1 1 10 100 Frequency (Hz)

Figure 51: RLGM for Watts Bar Nuclear Plant 5.2 Method to Estimate InStructure Response Spectra (ISRS)

EPRI SMA Methodology recommends that median centered response should be used in HCLPF calculations. The ISRS used in the updated IPEEE [12] are based on the NUREG0098 median shape for rock with a PGA of 0.5g. As shown on Figure 52 this shape is similar to the SSE spectrum. This figure also illustrates that the updated IPEEE [12] RLE spectrum with a PGA of 0.5g envelops the RLGM over the entire range of frequencies. Therefore, the median centered ISRS developed in the updated IPEEE

[12] represent the seismic demand on which the HCLPF values reported here are based.

Page 15

Watts Bar Nuclear Plant ESEP Report 1.20E+00 1.00E+00 8.00E01 Acceleration (g)

RLE NUREG/CR0098 (0.5g) 6.00E01 RLGM= 2x SSE 4.00E01 WBN SSE (0.18g) 2.00E01 0.00E+00 0.1 1 10 100 Frequency (Hz)

Figure 52: NUREG/CR0098 (0.5g) versus Watts Bar Nuclear Plant SSE 6.0 SEISMIC MARGIN EVALUATION APPROACH It is necessary to demonstrate that ESEL items have sufficient seismic capacity to meet or exceed the demand characterized by the RLGM. The seismic capacity is characterized as the PGA for which there is a HCLPF. The PGA is associated with a specific spectral shape, in this case the 5%damped RLGM spectral shape. The HCLPF capacity must be equal to or greater than the RLGM PGA. The criteria for seismic capacity determination are given in Section 5 of EPRI 3002000704 [2].

There are two basic approaches for developing HCLPF capacities:

1. Deterministic approach using the conservative deterministic failure margin (CDFM) methodology of EPRI NP6041SL, A Methodology for Assessment of Nuclear Power Plant Seismic Margin (Revision 1) [8] .

2. Probabilistic approach using the fragility analysis methodology of EPRI TR103959, Methodology for Developing Seismic Fragilities [10] .

6.1 Summary of Methodologies Used WBNP performed a SMA for Unit 1 in 1998 [11] and completed an IPEEE Final Report for Unit 2 in 2014

[21]. The SMA consisted of screening walkdowns, functional evaluation, and HCLPF anchorage calculations. The screening walkdowns used the screening tables from Chapter 2 of EPRI NP6041 [8].

The walkdowns were conducted by engineers trained in EPRI NP 6041 (the engineers attended the EPRI SMA AddOn course in addition to the Seismic Qualification Utility Group (SQUG) Walkdown Screening and Seismic Evaluation Training Course), and were documented on Screening Evaluation Work Sheets from EPRI NP6041. Anchorage capacity calculations used the CDFM criteria from EPRI NP6041.

Seismic demand was the IPEEE Review Level Earthquake (RLE) for SMA (median NUREG/CR0098 [6]

ground response spectrum for rock anchored to 0.3g PGA).

Page 16

Watts Bar Nuclear Plant ESEP Report After submittal of the IPEEE Reports to the NRC and considering insights into the seismic ruggedness of WBN equipment obtained from the IPEEE reports, WBN performed updated HCLPF capacity evaluations. The updated HCLPF capacity evaluations focused on removing excess conservatism and determining HCLPF capacity in a more accurate manner. The updated HCLPF evaluations document a minimum HCLPF of 0.5g for components on the IPEEE SSEL [12].

Considering insights from the updated HCLPF evaluations, a minimum HCLPF of 0.5 g was selected as the RLE for the SMA in the ESEP. Figure 52 shows the median NUREG/CR0098 (0.5g) ground response spectrum selected as the RLE for the SMA in the ESEP, compared to the required ESEP RLGM response spectrum. The figure shows that the selected ESEP RLE envelops the required ESEP RLGM at all frequencies.

6.2 HCLPF Screening Process The screening capacity in EPRI NP6041 [8] Table 24 based on ground peak spectral accelerations of 1.2g exceeds the RLGM peak spectral acceleration. The anchorage capacity calculations were based on floor response spectra generated for the RLE. Therefore, equipment for which the screening caveats were met and for which the anchorage capacity exceeds the RLE seismic demand associated with the PGA of 0.5g can be screened out from ESEP seismic capacity determination because the HCLPF capacity exceeds the RLGM.

The combined Unit 1 and Unit 2 ESEL includes 452 items. Of these, 87 are valves, both poweroperated and relief. In accordance with Table 24 of EPRI NP6041 [8], active valves may be assigned a functional capacity of 1.2g peak spectral acceleration, and anchorage is not a failure mode if evaluation recommended for motoroperated valves in piping lines of 2 inches diameter or less is performed.

Therefore, valves on the ESEL may be screened out from ESEP seismic capacity determination, subject to the caveat regarding large extended operators on small diameter piping. Poweroperated valves were addressed in the WBNP Unit 1 and 2 IPEEE SMA. In the SMA, the valves were found to meet EPRI NP6041 Figures F25 and F26 (thus meeting the 1.2g peak spectral acceleration screening criteria) or to exceed the RLE floor response spectra on the basis of vendor seismic qualification reports.

The IPEEE SMA reviews covered 449 valves in Unit 1, and 27 valves described as Unit 0. This review focused on motoroperated valves on small diameter piping and valves at high elevations in the plant.

Relief valves were not included in the IPEEE review except for the poweroperated relief valves, which met the criteria. Springoperated relief valves are considered to meet the EPRI NP6041 1.2g peak spectral acceleration screening criteria without explicit review. On the basis of the above, the ESEL valves may be screened out from ESEP seismic capacity determination.

The nonvalve components in the ESEL are generally screened based on the SMA results. If the SMA showed that the component met the EPRI NP6041 screening caveats and the CDFM capacity exceeded the RLE demand, the component can be screened out from the ESEP capacity determination.

Individual instrumentation items are generically associated with instrument racks and instrument panels. These will be assigned HCLPF values based on similar assemblies evaluated in the IPEEE.

The ESEL includes an instrument loop for parameters monitored during the FLEX implementation. A typical loop consists of a probe or sensor, an indicator and/or transmitter on a local rack, a cabinet in the Auxiliary Instrument Room, an indicator in the Main Control Room, and an indicator in the Aux Control Room. Panels in the Main Control Room, Aux Control Room, and the Aux Instrument Room Page 17

Watts Bar Nuclear Plant ESEP Report have been screened by the updated IPEEE evaluation [12] as discussed above, and all probes or sensors will be boxed/mounted with their respective component.

6.3 Seismic Walkdown Approach 6.3.1 Walkdown Approach Walkdowns were performed in accordance with the criteria provided in Section 5 of EPRI 3002000704

[2], which refers to EPRI NP6041 [8] for the SMA process. Pages 226 through 230 of EPRI NP6041

[8] describe the seismic walkdown criteria, including the following key criteria.

The SRT [Seismic Review Team] should walk by 100% of all components which are reasonably accessible and in nonradioactive or low radioactive environments. Seismic capability assessment of components which are inaccessible, in highradioactive environments, or possibly within contaminated containment, will have to rely more on alternate means such as photographic inspection, more reliance on seismic reanalysis, and possibly, smaller inspection teams and more hurried inspections. A 100%

walk by does not mean complete inspection of each component, nor does it mean requiring an electrician or other technician to deenergize and open cabinets or panels for detailed inspection of all components. This walkdown is not intended to be a QA or QC review or a review of the adequacy of the component at the SSE level.

If the SRT has a reasonable basis for assuming that the group of components are similar and are similarly anchored, then it is only necessary to inspect one component out of this group. The similaritybasis should be developed before the walkdown during the seismic capability preparatory work (Step 3) by reference to drawings, calculations, or specifications. The one component or each type which is selected should be thoroughly inspected which probably does mean deenergizing and opening cabinets or panels for this very limited sample. Generally, a spare representative component can be found so as to enable the inspection to be performed while the plant is in operation. At least for the one component of each type which is selected, anchorage should be thoroughly inspected.

The walkdown procedure should be performed in an ad hoc manner. For each class of components the SRT should look closely at the first items and compare the field configurations with the construction drawings and/or specifications. If a onetoone correspondence is found, then subsequent items do not have to be inspected in as great a detail. Ultimately the walkdown becomes a walk by of the component class as the SRT becomes confident that the construction pattern is typical. This procedure for inspection should be repeated for each component class; although, during the actual walkdown the SRT may be inspecting several classes of components in parallel. If serious exceptions to the drawings or questionable construction practices are found then the system or component class must be inspected in closer detail until the systematic deficiency is defined.

The 100% walk by is to look for outliers, lack of similarity, anchorage which is different from that shown on drawings or prescribed in criteria for that component, potential SI [Seismic Interaction]

problems, situations that are at odds with the team members past experience, and any other areas of serious seismic concern. If any such concerns surface, then the limited sample size of one component of each type for thorough inspection will have to be increased. The increase in sample size which should be inspected will depend upon the number of outliers and different anchorages, etc., which are observed. It is up to the SRT to ultimately select the sample size since they are the ones who are responsible for the seismic adequacy of all elements which they screen from the margin review.

Appendix D gives guidance for sampling selection.

Page 18

Watts Bar Nuclear Plant ESEP Report Attachment A was consolidated from the 452 components into a walkdown list containing 210 components. Consolidated from this list are components in the previously credited walkdowns and components that are mounted on or boxed into other components. The details of these walkdown are summarized in ESEP Walkdown Package [19].

6.3.2 Application of Previous Walkdown Information Previous seismic walkdowns were used to support the ESEP seismic evaluations. Some of the components on the ESEL were included in the NTTF 2.3 seismic walkdowns [18]. Those walkdowns were recent enough that they did not need to be repeated for the ESEP.

Several ESEL items were previously walked down during the WBNP Unit 1 and 2 Seismic IPEEE program.

Additionally, previous walkdowns performed as part of the Unit 1 and Unit 2 Integrated Interaction Program (IIP) and Equipment Seismic Qualification (ESQ) Programs as referenced in the WBN Unit 1 and Unit 2 IPEEE reports are also credited. Those walkdown results were reviewed and the following steps were taken to confirm that the previous walkdown conclusions remained valid.

A walk by was performed to confirm that the equipment material condition and configuration is consistent with the walkdown conclusions and that no new significant interactions related to block walls or piping attached to tanks exist.

If the ESEL item was screened out based on the previous walkdown, that screening evaluation was reviewed and reconfirmed for the ESEP.

The construction work on WBN2 is currently ongoing. However, the construction and equipment installation is sufficiently complete so that a seismic margins walkdown of items of equipment that are unique to the WBN2 ESEL could be performed. This walkdown was recently completed as part of the ESEP in accordance with the requirements of the EPRI SMA methodology.

6.3.3 Significant Walkdown Findings Consistent with the guidance from NP6041 [8], no significant outliers or anchorage concerns were identified during the WBNP seismic walkdowns. The following findings were noted during the walkdowns, but are not considered significant.

Several block walls were identified in the proximity of ESEL equipment. These block walls were also identified during the IPEEE walkdown and assessed for their structural adequacy to withstand the seismic loads resulting from the RLE. Per IPEEE, all block walls at Watts Bar exceed the HCLPF limit of the ESEP and are adequate [21].

WBN2DPL2681 - Panel is adjacent to block wall (corresponding Unit 1 panel is not near wall). As stated above, this block wall is adequate.

WBN0XSW2361/AS, WBN0XSW2362/AS, and WBN0XSW2363/AS - Panels are mounted on partition walls. The partition walls are load rated and considered part of building structure, thus the walls are not considered part of the scope for the ESEL.

WBN0PNL360FP/A, and FP/B - Both panels are in contact with, but not tied to, a cable tray support above. These interactions are judged to be credible, but not significant by the SRT.

Page 19

Watts Bar Nuclear Plant ESEP Report WBN2MCC213A1 - Motor Control Center (MCC) has interaction issue with an overhead cable tray support. This MCC was reviewed under the IPEEE evaluation for the plant and all potential interactions were resolved for RLGM [21].

WBN1PNL276L1000 - Two anchor bolts project from the floor about an inch higher than the typical installation. Embedment adequacy for these bolts is addressed and it has been verified that the minimum embedment for the anchors has been met.

The findings and other information developed from the ESEP walkdown are summarized in ESEP Walkdown Package [19]. Based on walkdown results, HCLPF capacity evaluations were recommended for the following twelve (12) components.

Motor Control Centers and Switchgear Transformers Control and Instrumentation Panels Instrument Racks Distribution Panels Engine Generators Horizontal Pumps Air Operated Valves Motor Operated Valves Vertical Tanks and Heat Exchangers Horizontal Tanks and Heat Exchangers Relays 6.4 HCLPF Calculation Process ESEL items not included in the previous updated IPEEE evaluations at WBNP were evaluated using the criteria in EPRI NP6041 [8]. Those evaluations included the following steps:

Performing seismic capability walkdowns for equipment not included in previous seismic walkdowns (SQUG, IPEEE, or NTTF 2.3) to evaluate the equipment installed plant conditions Performing screening evaluations using the screening tables in EPRI NP6041 as described in Section 6.2 Performing HCLPF calculations considering various failure modes that include both structural failure modes (e.g., anchorage, load path, etc.) and functional failure modes All HCLPF calculations were performed using the CDFM methodology and are documented in the Summary of HCLPF Calculations for WBNP ESEP [20]. The HCLPF capacities for functionality are based on the comparison of the demand (ISRS) with EPRI 6041 [8] screening level HCLPFs, GERS, or test response spectra. ESEL items not included in the previous updated IPEEE evaluations have HCLPF 0.5g.

Page 20

Watts Bar Nuclear Plant ESEP Report 6.5 Functional Evaluations of Relays ESEP considers cabinets and equipment controls containing relays, contactors, switches, circuit breakers and other electrical and instrumentation components that could be affected by high frequency earthquake motions and that impact operation of equipment in the ESEL.

A focused scope SMA was performed to support the IPEEE for WBNP as summarized in the February 1998 WBNP Unit 1 IPEEE submittal [11] and the November 2014 WBNP Unit 2 IPEEE Final Report [21].

The relay evaluation for a focusedscope plant is limited to a review of low seismic ruggedness relays (bad actor relays). The relay evaluation documented that there are no low seismic ruggedness relays used in applications which qualify them as essential relays.

In 2013, as part of the additional evaluations to document a HCLPF of 0.5g, a relay seismic functionality evaluation was performed for Unit 1 and 2. The purpose of the relay functionality evaluation was to verify that safe shutdown systems modeled in the WBN IPEEE would not be prevented from performing their safe shutdown functions because of relay (contact) chatter during the period of strong motion. The relay evaluation found that relay (contact) chatter during the period of strong motion would not prevent safe shutdown systems in the WBN IPEEE from performing their safe shutdown functions [22].

For the WBNP ESEP Analysis, an evaluation was performed to identify components that are (1) needed for FLEX implementation, (2) not on the IPEEE SSEL, and (3) that have the potential for relay chatter issues. The evaluation identified two sets of components. The first set is System 46 relays associated with the auxiliary feedwater system. A HCLPF was calculated for the relays and in all cases, the HCLFP 0.5g [20]. The second set is the FCV117 and FCV118 steam isolation valves that can isolate the steam supply to the TDAFW pump. In the event of a steam line break, both of these valves can receive a close signal if high temperature is detected in the TDAFW pump room. However, because these valves are motor operated valves (MOV), with a Loss of Offsite Power (LOOP) the valves will not isolate even with a spurious close signal. Therefore, these valves do not present a problem for successful FLEX implementation.

6.6 Tabulated ESEL HCLPF Values (Including Key Failure Modes)

Tabulated ESEL HCLPF values are provided in Attachment B for Unit 1 and Unit 2 items, as well as for items common to both units. The following notes apply to the information in the tables.

For items screened out using NP 6041 [8] screening tables, the screening level is provided as

>RLGM (0.5g) and the failure mode is listed as Screened, (unless the controlling HCLPF value is governed by anchorage).

For items where anchorage controls the HCLPF value, the HCLPF value is listed in the table and the failure mode is noted as anchorage.

7.0 INACCESSIBLE ITEMS 7.1 Identification of ESEL items inaccessible for walkdowns As concluded by ESEP Walkdown Package [19], no items on the ESEL were judged to require any further walkdowns to satisfy the ESEP evaluation Page 21

Watts Bar Nuclear Plant ESEP Report 7.2 Planned Walkdown / Evaluation Schedule / Close Out Unit 1 Containment was not accessible during the walk by verifications. The ESEL components inside the Unit 1 Containment are the same as those inside the Unit 2 Containment. Detailed closeup inspection of all ESEL components was performed for the components inside Unit 2 Containment. All of these Unit 2 ESEL components inside Unit 2 Containment were found to be well constructed, seismically rugged, and had adequate commodity clearance. The TVA Watts Bar radiation protection and operations groups maintain current photographs of all areas inside Unit 1 Containment. These photographs were made available to the walkdown team. The ESEP walkdown team reviewed the photographs and concluded that the ESEL components inside Unit 1 Containment are the same as those inside Unit 2 Containment. It was also concluded that the components were well constructed, seismically rugged, and had adequate commodity clearance [24]. Based on these observations, as concluded by the ESEP Walkdown Package [19], it is judged that no items on the ESEL require any further walkdowns to satisfy the ESEP evaluation.

8.0 ESEP CONCLUSIONS AND RESULTS 8.1 Supporting Information WBNP has performed the ESEP as an interim action in response to the NRCs 50.54(f) letter [1]. It was performed using the methodologies in the NRC endorsed guidance in EPRI 3002000704 [2].

The ESEP provides an important demonstration of Seismic Margin and expedites plant safety enhancements through evaluations and potential nearterm modifications of plant equipment that can be relied upon to protect the Reactor Core following beyond design basis seismic events.

The ESEP is part of the overall WBNP response to the NRCs 50.54(f) letter [1]. On March 12, 2014, NEI submitted to the NRC results of a study [13] of seismic core damage risk estimates based on updated seismic hazard information as it applies to operating nuclear reactors in the Central and Eastern United States (CEUS). The study concluded that sitespecific seismic hazards show that there [] has not been an overall increase in seismic risk for the fleet of U.S. plants based on the reevaluated seismic hazards. As such, the current seismic design of operating reactors continues to provide a safety margin to withstand potential earthquakes exceeding the seismic design basis.

The NRCs May 9, 2014 NTTF 2.1 Screening and Prioritization letter [15] concluded that the fleetwide seismic risk estimates are consistent with the approach and results used in the Gl199 safety/risk assessment. The letter also stated that As a result, the staff has confirmed that the conclusions reached in Gl199 safety/risk assessment remain valid and that the plants can continue to operate while additional evaluations are conducted.

An assessment of the change in seismic risk for WBNP was included in the fleet risk evaluation submitted in the March 12, 2014 NEI letter [13] therefore, the conclusions in the NRCs May 9 letter

[15] also apply to WBNP.

In addition, the March 12, 2014 NEI letter [13] provided an attached Perspectives on the Seismic Capacity of Operating Plants, which (1) assessed a number of qualitative reasons why the design of SSCs inherently contain margin beyond their design level, (2) discussed industrial seismic experience databases of performance of industry facility components similar to nuclear SSCs, and (3) discussed earthquake experience at operating plants.

Page 22

Watts Bar Nuclear Plant ESEP Report The fleet of currently operating NPPs was designed using conservative practices, such that the plants have significant margin to withstand large ground motions safely. This has been borne out for those plants that have actually experienced significant earthquakes. The seismic design process has inherent (and intentional) conservatisms which result in significant seismic margins within SSCs. These conservatisms are reflected in several key aspects of the seismic design process, including:

Safety factors applied in design calculations Damping values used in dynamic analysis of SSCs Bounding synthetic time histories for ISRS calculations Broadening criteria for ISRS Response spectra enveloping criteria typically used in SSCs analysis and testing applications Response spectra based frequency domain analysis, rather than explicit time history based time domain analysis Bounding requirements in codes and standards Use of minimum strength requirements of structural components (concrete and steel)

Bounding testing requirements Ductile behavior of the primary materials (that is, not crediting the additional capacity of materials such as steel and reinforced concrete beyond the essentially elastic range, etc.)

These design practices combine to result in margins such that the SSCs will continue to fulfill their functions at ground motions well above the SSE.

The intent of the ESEP is to perform an interim action in response to the NRCs 50.54(f) letter [1] to demonstrate Seismic Margin through a review of a subset of the plant equipment that can be relied upon to protect the Reactor Core following beyond design basis seismic events. In order to complete the ESEP in an expedited amount of time, the RLGM used for the ESEP evaluation is a scaled version of the plants SSE rather than the actual GMRS. To more fully characterize the risk impacts of the seismic ground motion represented by the GMRS on a plantspecific basis, a more detailed seismic risk assessment (SPRA or riskbased SMA) is to be performed in accordance with EPRI 1025287 [16]. As identified in the WBNP Seismic Hazard and GMRS submittal [4], WBNP screens in for a risk evaluation.

The complete risk evaluation will more completely characterize the probabilistic seismic ground motion input into the plant, the plant response to that probabilistic seismic ground motion input, and the resulting plant risk characterization. WBNP will complete that evaluation in accordance with the schedule identified in NEIs letter dated April 9, 2013 [14] and endorsed by the NRC in their May 7, 2013 letter [17].

8.2 Identification of Planned Modifications Based on the HCLPF values assigned according to the methodology described in Section 6.0, no necessary planned modifications are identified.

8.3 Modification Implementation Schedule Per Section 8.2 above, no scheduling of modifications is required.

Page 23

Watts Bar Nuclear Plant ESEP Report 8.4 Summary of Regulatory Commitments There are no additional actions to be performed as a result of the ESEP.

Page 24

Watts Bar Nuclear Plant ESEP Report

9.0 REFERENCES

1. NRC 2012, Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3 and 9.3 of the NearTerm Task Force Review of Insights from the Fukushima DaiIchi Accident, Nuclear Regulatory Commission, March 2012.

2. Electric Power Research Institute (EPRI) 3002000704, Seismic Evaluation Guidance:

Augmented Approach for the Resolution of Fukushima NearTerm Task Force Recommendation 2.1Seismic, May 31, 2013.

3. Tennessee Valley Authority (TVA), Revised Overall Integrated Plan in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for BeyondDesignBasis External Events (Order Number EA12049) for Watts Bar Nuclear Plant (TAC Nos. MF0950 and MF1177), February 7, 2014.

4. TVA, CNL14038, Seismic Hazard and Screening Report(CEUS Sites), Enclosure 4 Seismic Hazard and Screening Report for Watts Bar Nuclear Plant, March 31, 2014.

5. EPRI, Watts Bar Seismic Hazard and Screening Report, Electric Power Research Institute, Palo Alto, CA, dated February 7, 2014.

6. N.M. Newmark Consulting Engineering Services, NUREG/CR0098, Development of Criteria for Seismic Review of Selected Nuclear Power Plants, 1978.

7. Not Used

8. EPRI 1991, A Methodology for Assessment of Nuclear Power Plant Seismic Margin, EPRI NP 6041SL, Revision 1, Electric Power Research Institute, Palo Alto, CA, USA, August 1991.

9. EPRI, 1991a, Seismic Ruggedness of Relays, EPRI, Palo Alto, California: August 1991, NP7147SL, 1991.

10. EPRI 1994, Methodology for Developing Seismic Fragilities, EPRI TR103959, Electric Power Research Institute, June 1994.

11. TVA, Watts Bar Nuclear Plant Unit 1 Individual Plant Evaluation of External Events - Final Report,1998.

12. TVA Calculation CDQ 000 999 2012 000125, Updated WBN Seismic IPEEE HCLPF Capacity, April 2014.

13. NEI 2014, Seismic Core Damage Risk Estimates Using the Updated Seismic Hazards for the Operating Nuclear Plants in the Central and Eastern United States, Nuclear Energy Institute, March 2014.

14. NEI 2013, Proposed Path Forward for NTTF Recommendation 2.1: Seismic Reevaluations, Nuclear Energy Institute, April 2013.

15. NRC 2014, Screening and Prioritization Results Regarding Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(F) Regarding Seismic Hazard ReEvaluations for Recommendation 2.1 of the NearTerm Task Force Review of Insights From the Fukushima DaiIchi Accident, Nuclear Regulatory Commission, May 2014.

Page 25

Watts Bar Nuclear Plant ESEP Report

16. EPRI 2013a, Seismic Evaluation Guidance: Screening, Prioritization and Implementation Details (SPID) for the resolution of Fukushima NearTerm Task Force Recommendation 2.1: Seismic, EPRI1025287, Electric Power Research Institute, February 2013

17. NRC 2013, Electric Power Research Institute Final Draft Report Xxxxxx, Seismic Evaluation Guidance: Augmented Approach for the Resolution of Fukushima NearTerm Task Force Recommendation 2.1: Seismic, as an Acceptable Alternative to the March 12, 2012, Information Request for Seismic Reevaluations, Nuclear Regulatory Commission, May 2013.

18. NRC ADAMs Number ML12353A251, Enclosure 1 Watts Bar Nuclear Plant, Unit 1 Fukushima NearTerm Task Force Recommendation 2.3: Seismic Response Report, 2012.

19. RIZZO, R15 ESEP Walkdown of Watts Bar Nuclear Plant Units 1 & 2, October 21, 2014.

20. RIZZO, F31, Summary of HCLPF Calculations for WBNP ESEP Report, October 21, 2014.

21 TVA, 2014, Watts Bar Nuclear Plant Unit 2 (WBN2) Individual Plant Examination of External Events (IPEEE), Revision 0, November 10, 2014.

22. Scientech, 2014, WBN2 Enhanced IPEEE Relay Chatter Analysis Report, Revision 0, March 4, 2014.

23. NEI 2013, Position Paper: Shutdown/Refueling Modes. Nuclear Energy Institute, September 2013. NRC ADAMS No. ML13273A514.

24. RIZZO, R12, Seismic Walkdown of Watts Bar Nuclear Plant Units 1 and 2 Seismic Probabilistic Risk Assessment Project, December 22, 2014.

25. TVA, 2014, Whitepaper Watts Bar Nuclear Plant Expedited Seismic Equipment List, December 20, 2014.

Page 26

Watts Bar Nuclear Plant ESEP Report ATTACHMENT A EXPEDITED SEISMIC EQUIPMENT LIST (ESEL) FOR WATTS BAR NUCLEAR PLANT Page A1

Watts Bar Nuclear Plant ESEP Report Table A1: EXPEDITED SEISMIC EQUIPMENT LIST (ESEL) FOR WATTS BAR NUCLEAR PLANT ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State Solid State WBN1PNL 1 Protection Operational Operational 099R48A System Train A Solid State WBN2PNL 2 Protection Operational Operational 099R50B System Train B Reactor WBN2PNL 3 Protection I Operational Operational 099R2D Process System Solid State WBN2PNL 4 Protection Operational Operational 099R48A System Train A Solid State WBN1PNL 5 Protection Operational Operational 099R50B System Train B Reactor WBN2PNL 6 Protection II Operational Operational 099R6E Process System WBN1PNL ICCM System 7 Operational Operational ICCM Train A Unit 1 Unit 1 Auxiliary Instrument Room 275R179A Train A CH 1 Common Q WBN2PNL Common Q Train A Unit 2 Unit 2 Auxiliary Instrument 8 PAMS Panel Operational Operational 275R179A Room Train A WBN1PNL ICCM System 9 Operational Operational ICCM Train B Unit 1 Unit 1 Auxiliary Instrument Room 275R180B Train B CH 2 Common Q WBN2PNL Common Q Train B unit 2 Unit 2 Auxiliary Instrument 10 PAMS Panel Operational Operational 275R180B Room Train B Page A2

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2HIC RX HEAD VENT 11 Operational Operational 0FSI8; Main Control Room panel M4 068396 FLOW CONTROL Solid State WBN2PNL 12 Protection Operational Operational 099R46A System Train A Solid State WBN2PNL 13 Protection Operational Operational 099R49B System Train B Reactor WBN2PNL 14 Protection II Operational Operational 099R6E Process System WBN1 SIS Accumulator 15 ACUM063 Operational Operational Tank 1 0001 WBN1 SIS Accumulator 16 ACUM063 Operational Operational Tank 2 0002 WBN1 SIS Accumulator 17 ACUM063 Operational Operational Tank 3 0003 WBN1 SIS Accumulator 18 ACUM063 Operational Operational Tank 4 0004 WBN0BAT 125 V Vital 19 Operational Operational 2360001D Battery I WBN0BAT 125 V Vital 20 Operational Operational 2360002E Battery II WBN0BAT 125 V Vital 21 Operational Operational 2360003F Battery III Page A3

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN0BAT 125 V Vital 22 Operational Operational 2360004G Battery IV WBN1BD 6.9 KV Shutdown 23 Operational Operational Primary Path OIP Figure A324, 25, and 26 211AA Board 1AA WBN2BD 6.9 KV Shutdown Primary Path OIP Figure A324 and A326.

24 Operational Operational 211BB Board 2BB Also, see ESEL Item 200.

WBN1BD 480V Shutdown 25 Operational Operational 212A001A Board 1A1A WBN2BD 480V Shutdown 26 Operational Operational Component Cooling System Pump 2AA 212A001A Board 2A1A WBN1BD 480V Shutdown 27 Operational Operational Primary Path OIP Figure A324, 25, and 26 212A002A Board 1A2A WBN2BD 480V Shutdown 28 Operational Operational Containment Air Return Fan 39. ESEL # 146.

212B002B Board 2B2B WBN0BD 125V Vital 29 Operational Operational 2360001D Battery Board I WBN0BD 125V Vital 30 Operational Operational 2360002E Battery Board II WBN0BD 125V Vital 31 Operational Operational 2360003F Battery Board III WBN0BD 125V Vital 32 Operational Operational 2360004G Battery Board IV WBN0CHGR 125 V Vital 33 Operational Operational 2360001D Battery Charger I 125 V Vital WBN0CHGR 34 Battery Charger Operational Operational 2360002/E II Page A4

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State 125 V Vital WBN0CHGR 35 Battery Charger Operational Operational 2360003/F III 125 V Vital WBN0CHGR 36 Battery Charger Operational Operational 2360004/G IV WBN1HTX CCS HEAT 37 Operational Operational Flow path to support SIP lube oil cooler 0700185 EXCHANGER A WBN2HTX CCS HEAT 38 Operational Operational Flow path to support SIP lube oil cooler 0700185 EXCHANGER B WBN1HTX RHR HEAT RWST gravity feed path 39 Operational Operational 0740030A EXCHANGER 1A Flow path to support SIP lube oil cooler WBN2HTX RHR HEAT RWST gravity feed path 40 Operational Operational 0740031A EXCHANGER 2A Flow path to support SIP lube oil cooler WBN1INV 120 V AC Vital 41 Operational Operational 2350001D Inverter 1I WBN2INV 120 V AC Vital 42 Operational Operational 2350001D Inverter 2I WBN1INV 120 V AC Vital 43 Operational Operational 2350002E Inverter 1II WBN2INV 120 V AC Vital 44 Operational Operational 2350002E Inverter 2II WBN1INV 120 V AC Vital 45 Operational Operational 2350003F Inverter 1III WBN2INV 120 V AC Vital 46 Operational Operational 2350003F Inverter 2III WBN1INV 120 V AC Vital 47 Operational Operational 2350004G Inverter 1IV Page A5

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2INV 120 V AC Vital 48 Operational Operational 2350004G Inverter 2IV 480V Reactor WBN1MCC FCV6380 and 118 Cold Leg 1 and 3 Accumulator 49 MOV Board 1A1 Operational Operational 213A001A Isolation A

480V Reactor WBN2MCC FCV6380 and 118 Cold Leg 1 and 3 Accumulator 50 MOV Board 2A1 Operational Operational 213A001A Isolation A

480V Reactor WBN1MCC FCV6398 and 67 Cold Leg 2 and 4 Accumulator 51 MOV Board 1B1 Operational Operational 213B001B Isolation B

480V Reactor WBN2MCC FCV6398 and 67 Cold Leg 2 and 4 Accumulator 52 MOV Board 2B1 Operational Operational 213B001B Isolation B

Cont & Aux Bldg WBN1MCC 53 Vent Board 1A1 Operational Operational H2 igniters U1A 214A001A A

Cont & Aux Bldg WBN2MCC 54 Vent Board 2B1 Operational Operational H2 igniters U2B 214B001B B

Cont & Aux Bldg WBN1MCC 55 Vent Board 1A2 Operational Operational 2 IP & 1 HP FLEX Pump. OIP Figure A323 214A002A A

Cont & Aux Bldg WBN2MCC 56 Vent Board 2B2 Operational Operational 2 IP & 2 HP FLEX Pump. OIP Figure A323 214B002B B

480 V WBN1OXF 57 Transformer Operational Operational 212A001A 1A1A Page A6

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State 480 V WBN2OXF 58 Transformer Operational Operational 212A001A 2A1A 480 V WBN1OXF 59 Transformer Operational Operational OIP Figure A324 and 26 , Primary Path 212A002A 1A2A 480 V WBN2OXF 60 Transformer Operational Operational OIP Figure A324 and 26 , Primary Path 212B002B 2B2B Centrifugal WBN1PMP Pump oil cooler in flow path to support SIP lube oil 61 Charging Pump Operational Operational 0620108A cooler 1AA Centrifugal WBN2PMP Pump 0il cooler in flow path to support SIP lube oil 62 Charging Pump Operational Operational 0620108A cooler 2AA SAFETY WBN1PMP 63 INJECTION PUMP Operational Operational OIP Figure A325 Primary Path 0630010A 1AA SAFETY WBN2PMP 64 INJECTION PUMP Operational Operational OIP Figure A325 Primary Path 0630010A 2AA Component WBN1PMP 65 Cooling System Operational Operational support SIP lube oil cooler 0700046A Pump 1AA Component WBN2PMP 66 Cooling System Operational Operational support SIP lube oil cooler 0700059A Pump 2AA WBN1PMP seal water heat exchanger in flow path 67 RHR PUMP 1AA Operational Operational 0740010A for SIP lube oil cooler Page A7

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2PMP seal water heat exchanger in flow path 68 RHR PUMP 2BB Operational Operational 0740020B for SIP lube oil cooler Steam Generator WBN1PNL 69 Level Control Operational Operational Auxiliary Control Room 276L011A Panel Steam Generator WBN2PNL 70 Level Control Operational Operational Auxiliary Control Room 276L011A Panel Steam Generator WBN1PNL 71 Level Control Operational Operational Auxiliary Control Room 276L011B Panel Steam Generator WBN2PNL 72 Level Control Operational Operational Auxiliary Control Room 276L011B Panel UNIT CONT.

WBN1PNL Main Control Room Panels M1 through M6 73 BOARD PNL 1M Operational Operational 278M003 3

UNIT CONT.

WBN2PNL Main Control Room Panels M1 through M6 74 BOARD PNL 2M Operational Operational 278M003 3

UNIT CONT.

WBN1PNL 75 BOARD PNL 1M Operational Operational Main Control Room Panels M1 through M6 278M004 4

UNIT CONT.

WBN2PNL 76 BOARD PNL 2M Operational Operational Main Control Room Panels M1 through M6 278M004 4

WBN1PNL TEMPERATURE 77 Operational Operational Main Control Room Panel 278M010 MONITORING Page A8

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2PNL TEMPERATURE 78 Operational Operational Main Control Room Panel 278M010 MONITORING WBN1, 2 7 Day Fuel Oil 1TANK1838 DG A, 1TANK1841 DG 3B 79 TANK18 Available Available Sup Dsl Gen 2TANK1838 DG 3A, 2TANK1841 DG B 38,41 WBN1TANK Refueling Water 80 Operational Operational Cool without SG & RCS inventory 0630046 Storage Tank WBN2TANK Refueling Water 81 Operational Operational Cool without SG & RCS inventory 0630046 Storage Tank Component WBN1TANK 82 Cooling Water Operational Operational Flow path to support SIP lube oil cooler 0700001 Surge Tank Component WBN2TANK 83 Cooling Water Operational Operational Flow path to support SIP lube oil cooler 0700001 Surge Tank CVCS SEAL WBN1FCV 84 WATER RETURN Operational Operational ECA 0.0 App. A isolate RCP seal return 0620063A HEADER ISOL CVCS SEAL WBN2FCV 85 WATER RETURN Operational Operational ECA 0.0 App A isolate RCP seal return 0620063A HEADER ISOL Accumulator WBN1FCV 86 Isolation Valve Operational Operational 480V RMOV Bd ESEL Item # 51 0630067 4

Accumulator WBN2FCV 87 Isolation Valve Operational Operational 480V RMOV Bd ESEL Item # 52 0630067 4

WBN1FCV Accumulator 88 Operational Operational 480V RMOV Bd ESEL Item # 49 0630080 Isolation Valve 3 Page A9

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2FCV Accumulator 89 Operational Operational 480V RMOV Bd ESEL Item # 50 0630080 Isolation Valve 3 WBN1FCV LWR CNTMT A 90 Open Closed FSI5.05 Appendix A 0670083 CLRS SUP CIV WBN1FCV Accumulator 91 Operational Operational 480V RMOV Bd ESEL Item # 51 0630098 Isolation Valve 2 WBN2FCV Accumulator 92 Operational Operational 480V RMOV Bd ESEL Item # 52 0630098 Isolation Valve 2 WBN1FCV Accumulator 93 Operational Operational 480V RMOV Bd ESEL Item # 49 0630118 Isolation Valve 1 WBN2FCV Accumulator 94 Operational Operational 480V RMOV Bd ESEL Item # 50 0630118 Isolation Valve 1 WBN2FCV LWR CNTMT A 95 Open Closed FSI5.05 App. A: align ERCW header 0670083 CLRS SUP CIV WBN1FCV LWR CNTMT C 96 Open Closed FSI5.05 App. A: align ERCW header 0670091 CLRS SUP CIV WBN2FCV LWR CNTMT C 97 Open Closed FSI5.05 App. A: align ERCW header 0670091 CLRS SUP CIV WBN1FCV LWR CNTMT B 98 Open Closed FSI5.05 App. A: align ERCW header 0670099 CLRS SUP CIV WBN2FCV LWR CNTMT B 99 Open Closed FSI5.05 App. A: align ERCW header 0670099 CLRS SUP CIV WBN1FCV LWR CNTMT D 100 Open Closed FSI5.05 App. A: align ERCW header 0670107 CLRS SUP CIV WBN2FCV LWR CNTMT D 101 Open Closed FSI5.05 App. A: align ERCW header 0670107 CLRS SUP CIV WBN1FCV UPR CNTMT CLR 102 Open Closed FSI5.05 App. A: align ERCW header 0670130 A SUP CIV Page A10

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2FCV UPR CNTMT CLR 103 Open Closed FSI5.05 App. A: align ERCW header 0670130 A SUP CIV WBN1FCV UPR CNTMT CLR 104 Open Closed FSI5.05 App. A: align ERCW header 0670133 C SUP CIV WBN2FCV UPR CNTMT CLR 105 Open Closed FSI5.05 App. A: align ERCW header 0670133 C SUP CIV WBN1FCV UPR CNTMT CLR 106 Open Closed FSI5.05 App. A: align ERCW header 0670138 B SUP CIV WBN2FCV UPR CNTMT CLR 107 Open Closed FSI5.05 App. A: align ERCW header 0670138 B SUP CIV WBN1FCV UPR CNTMT CLR 108 Open Closed FSI5.05 App. A: align ERCW header 0670141 D SUP CIV WBN2FCV UPR CNTMT CLR 109 Open Closed FSI5.05 App. A: align ERCW header 0670141 D SUP CIV WBN2FCV CCS HX DISCH to 110 Open Closed FSI5.05 App. A: align ERCW header 0670143 HDR B WBN1FCV CCS HX DISCH to 111 Open Closed FSI5.05 App. A: align ERCW header 0670143 HDR B WBN0FCV CCS HX C DISCH 112 Operational Operational FS15.05 step 16 0670144 to HDR A PRESSURIZER WBN2FCV 113 PORV BLOCK Open Open 0FSI8, Train B 0680332B VALVE PRESSURIZER WBN1FCV 114 PORV BLOCK Open Open 0FSI8, Train A 0680333 VALVE RC Pump Therm WBN1FCV 115 Barrier Ret Operational Operational ECA 0.0 App. A Isolate thermal barrier 0700090A CNTNMT Isol Page A11

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State RC Pump Therm WBN2FCV 116 Barrier Ret Operational Operational ECA 0.0 App. A Isolate thermal barrier 0700090A CNTNMT Isol RC Thermal WBN1FCV 117 Barrier Cont Isol Operational Operational ECA 0.0 App. A Isolate thermal barrier 0700133A Valve RC Thermal WBN2FCV 118 Barrier Cont Isol Operational Operational ECA 0.0 App. A Isolate thermal barrier 0700133A Valve TD AFW PUMP Fails open on loss of AC power or control air.

WBN2LCV 119 SG # 2 Level Operational Operational Backup N2 supply bottles available.

0020173B Control Manual operation with hand wheel is available.

TD AFW PUMP Fails open on loss of AC power or control air.

WBN1LCV 120 SG # 3 Level Operational Operational Backup N2 supply bottles available.

0030172A Control Manual operation with hand wheel is available.

TD AFW PUMP Fails open on loss of AC power or control air.

WBN2LCV 121 SG # 3 Level Operational Operational Backup N2 supply bottles available.

0030172A Control Manual operation with hand wheel is available.

TD AFW PUMP Fails open on loss of AC power or control air.

WBN1LCV 122 SG # 2 Level Operational Operational Backup N2 supply bottles available.

0030173B Control Manual operation with hand wheel is available.

Page A12

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State TD AFW PUMP Fails open on loss of AC power or control air.

WBN1LCV 123 SG # 1 Level Operational Operational Backup N2 supply bottles available.

0030174B Control Manual operation with hand wheel is available.

TD AFW PUMP Fails open on loss of AC power or control air.

WBN2LCV 124 SG # 1 Level Operational Operational Backup N2 supply bottles available.

0030174B Control Manual operation with hand wheel is available.

TD AFW PUMP Fails open on loss of AC power or control air.

WBN1LCV 125 SG # 4 Level Operational Operational Backup N2 supply bottles available.

0030175A Control Manual operation with hand wheel is available.

TD AFW PUMP Fails open on loss of AC power or control air.

WBN2LCV 126 SG # 4 Level Operational Operational Backup N2 supply bottles available.

0030175A Control Manual operation with hand wheel is available.

SG 1Main STM WBN1PCV Backup N2 supply bottles available; 127 HDR PWR Relief Operational Operational 0010005T Manual operation with hand wheel is available 0FSI7.

Control Valve SG 1Main STM WBN2PCV Backup N2 supply bottles available; 128 HDR PWR Relief Operational Operational 0010005T Manual operation with hand wheel is available 0FSI7.

Control Valve SG 2 Main STM WBN1PCV Backup N2 supply bottles available; 129 HDR PWR Relief Operational Operational 0010012T Manual operation with hand wheel is available 0FSI7.

Control Valve Page A13

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State SG 2 Main STM WBN2PCV Backup N2 supply bottles available; 130 HDR PWR Relief Operational Operational 0010012T Manual operation with hand wheel is available 0FSI7.

Control Valve SG 3 Main STM WBN1PCV Backup N2 supply bottles available; 131 HDR PWR Relief Operational Operational 0010023T Manual operation with hand wheel is available 0FSI7.

Control Valve SG 3 Main STM WBN2PCV Backup N2 supply bottles available; 132 HDR PWR Relief Operational Operational 0010023T Manual operation with hand wheel is available 0FSI7.

Control Valve SG 4Main STM WBN1PCV Backup N2 supply bottles available; 133 HDR PWR Relief Operational Operational 0010030T Manual operation with hand wheel is available 0FSI7.

Control Valve SG 4Main STM WBN2PCV Backup N2 supply bottles available; 134 HDR PWR Relief Operational Operational 0010030T Manual operation with hand wheel is available 0FSI7.

Control Valve WBN2PCV PRESSURIZER 135 Closed Operational 0FSI8, 125V DC Vital Battery Board II 0680334 PORV WBN1PCV PRESSURIZER 136 Closed Operational 0FSI8, 125V DC Vital Battery Board I 0680340A PORV Steam Generator WBN1SFV 137 #3 Main Steam Closed Operational 0010512 Safety Valve Steam Generator WBN2SFV 138 #3 Main Steam Closed Operational 0010512 Safety Valve Steam Generator WBN1SFV 139 #2 Main Steam Closed Operational 0010517 Safety Valve Page A14

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State Steam Generator WBN2SFV 140 #2 Main Steam Closed Operational 0010517 Safety Valve Steam Generator WBN1SFV 141 #1 Main Steam Closed Operational 0010522 Safety Valve Steam Generator WBN2SFV 142 #1 Main Steam Closed Operational 0010522 Safety Valve Steam Generator WBN1SFV 143 #4 Main Steam Closed Operational 0010527 Safety Valve Steam Generator WBN2SFV 144 #4 Main Steam Closed Operational 0010527 Safety Valve WBN1FAN Containment Air 145 Operational Operational 480V SD Bd A1A, ESEL # 25.

0300038 Return Fan AA WBN2FAN Containment Air 146 Operational Operational 480V SD Bd B2B, ESEL # 28 0300039 Return Fan BB AC OUTPUT WBN1EI235 147 AMMETER Operational Operational 0FSI7. 125V vital battery board voltage 001/A1 INVERTER 1I 120 V AC Vital WBN1BD 148 Instrument Operational Operational 2350001D Power Board 1I AC OUTPUT WBN1EI235 149 AMMETER Operational Operational 0FSI7. 125V vital battery board voltage 002/A1 INVERTER 1II Page A15

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State 120 V AC Vital WBN1BD 150 Instrument Operational Operational 2350002E Power Board 1II 120 V AC Vital WBN1BD 151 Instrument Operational Operational 2350003F Power Board 1III 120 V AC Vital WBN1BD Instrument 152 Operational Operational 2350004G Power Board 1 IV WBN1CLR CCP 1AA LUBE 153 Operational Operational Flow path to support SIP lube oil cooler 0620108AA OIL COOLER WBN1CLR CCP 1AA GEAR 154 Operational Operational Flow path to support SIP lube oil cooler 0620108BA OIL COOLER SAFETY WBN1CLR INJECTION PUMP 155 Operational Operational Flow path to support SIP lube oil cooler 0630010 1AA LUBE OIL COOLER CNTMT SPRAY WBN1CLR 156 PUMP 1AA OIL Operational Operational Flow path to support SIP lube oil cooler 0720027 COOLER RHR PUMP 1AA WBN1HTX SEAL WATER 157 Operational Operational Flow path to support SIP lube oil cooler 0740010A HEAT EXCHANGER WBN1XS STM GEN #3 TRF 158 Operational Operational Auxiliary Control Room panel L11A 0030172AA SW WBN1XS STM GEN #4 TRF 159 Operational Operational Auxiliary Control Room panel L11A 0030175AA SW Page A16

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN1XS STM GEN #2 TRF 160 Operational Operational Auxiliary Control Room panel L11B 0030173AB SW WBN1XS STM GEN #1 TRF 161 Operational Operational Auxiliary Control Room panel L11B 0030174AB SW WBN1XI046 TURB AFWP 162 Operational Operational Main Control Room panel M3 57 DEMAND AUX FPT FLOW WBN1FIC 163 IND Operational Operational Main Control Room panel M4 0460057AS CONTROLLER TD AFW PMP Trip/Throttle Valve WBN1HS 164 Handswitch Operational Operational Main Control Room panel M4 0460056AS AUTO MAN REMOTE SP FOR FIC4657B WBN1SI046 AFWT AS 165 Operational Operational Main Control Room panel M4 0056AS SPEED WBN1XI046 AFWT AS 166 Operational Operational Main Control Room panel M4 0054A MOP POSITION WBN1XI068 167 Plasma Display Operational Operational ICCM Train A Unit 1 Main Control Room 0100 WBN1XS Plasma Display 168 Operational Operational ICCM Train A Unit 1 Main Control Room 0680101 Key Pad WBN1HS RCS PRZR PWR 169 Operational Operational Main Control Room panel M5 068340AA RELIEF VALVE Common Q WBN2CPU Operator 170 Operational Operational Common Q Train B unit 2 Main Control Room 0946000 Module Node Box Page A17

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2FOC Common Q first 171 Operational Operational Common Q Train B unit 2 Main Control Room 0944001A modem WBN1HIC RX HEAD VENT 172 Operational Operational Main Control Room panel M6 068397 FLOW CONTROL WBN2HS SIS PUMP AA 173 Operational Operational Main Control Room panel M6 0630010A MOTOR WBN1HS SIS PUMP AA 174 Operational Operational Main Control Room panel M6 0630010A MOTOR WBN1HS AIR RET FAN AA 175 Operational Operational Main Control Room panel M9 0300038A ON/OFF WBN2HS AIR RET FAN BB 176 Operational Operational Main Control Room panel M9 0300039B ON/OFF AC OUTPUT WBN2EI235 177 AMMETER Operational Operational 125V Vital Battery Board Voltage 001/A1 INVERTER 2I 120 V AC Vital WBN2BD 178 Instrument Operational Operational 2350001D Power Board 2I 120 V AC Vital WBN2BD 179 Instrument Operational Operational 2350002E Power Board 2II AC OUTPUT WBN2EI235 180 AMMETER Operational Operational 125V Vital Battery Board Voltage 002/A1 INVERTER 2II 120 V AC Vital WBN2BD 181 Instrument Operational Operational 2350003F Power Board 2III Page A18

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State 120 V AC Vital WBN2BD Instrument 182 Operational Operational 2350004G Power Board 2 IV WBN2CLR CCP 2AA LUBE 183 Operational Operational Flow path to support SIP lube oil cooler 0620108 AA OIL COOLER WBN2CLR CCP 2AA GEAR 184 Operational Operational Flow path to support SIP lube oil cooler 0620108BA OIL COOLER SAFETY WBN2CLR INJECTION PUMP 185 Operational Operational Flow path to support SIP lube oil cooler 0630010 2AA LUBE OIL COOLER CNTMT SPRAY WBN2CLR 186 PUMP 2AA OIL Operational Operational Flow path to support SIP lube oil cooler 0720027 COOLER RHR PUMP 2AA WBN2HTX SEAL WATER 187 Operational Operational Flow path to support SIP lube oil cooler 0740010A HEAT EXCHANGER WBN2XS STM GEN #3 TRF 188 Operational Operational Auxiliary Control Room panel L11A 0030172AA SW WBN2XS STM GEN #4 TRF 189 Operational Operational Auxiliary Control Room panel L11A 0030175AA SW WBN2XS STM GEN #2 TRF 190 Operational Operational Auxiliary Control Room panel L11B 0030173AB SW WBN2XS STM GEN #1 TRF 191 Operational Operational Auxiliary Control Room panel L11B 0030174AB SW WBN2XI046 TURB AFWP 192 Operational Operational Main Control Room Panel M3 57 DEMAND Page A19

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State AUX FPT FLOW WBN2FIC 193 IND Operational Operational Main Control Room panel M4 0460057AS CONTROLLER TD AFW PMP Trip/Throttle Valve WBN2HS 194 Handswitch Operational Operational Main Control Room panel M4 0460056AS AUTO MAN REMOTE SP FOR FIC4657B WBN2SI046 AFWT AS 195 Operational Operational Main Control Room panel M4 0056AS SPEED WBN2XI046 AFWT AS 196 Operational Operational Main Control Room panel M4 0054A MOP POSITION WBN2HS RCS PRZR REL 197 Operational Operational Main Control Room panel M5 068333A FLOW CONTROL WBN2HIC RX HEAD VENT 198 Operational Operational Main Control Room panel M6 068397 FLOW CONTROL WBN2MON Plasma Touch 199 Operational Operational Common Q Train B Unit 2 Main Control Room 0680110 Screen Display WBN2BD 6.9kV Shutdown 200 Operational Operational Primary Path OIP Figure A325 211AA Board 2AA WBN2 SIS Accumulator 201 ACUM063 Operational Operational Tank 1 0001 WBN2 SIS Accumulator 202 ACUM063 Operational Operational Tank 2 0002 Page A20

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2 SIS Accumulator 203 ACUM063 Operational Operational Tank 3 0003 WBN2 SIS Accumulator 204 ACUM063 Operational Operational Tank 4 0004 WBN1HIC RX HEAD VENT 205 Operational Operational 0FSI8 068396 FLOW CONTROL Reactor WBN1PNL 206 Protection I Operational Operational 099R2D Process System Solid State WBN1PNL 207 Protection Operational Operational 099R46A System Train A Solid State WBN1PNL 208 Protection Operational Operational 099R49B System Train B Reactor WBN1PNL 209 Protection II Operational Operational 099R6E Process System WBN1PMP Containment 210 Operational Operational seal water HX in flow path to support SIP oil cooler 0720027A Spray Pump 1AA MAIN STEAM LOOP 4 WBN2PI001 211 PRESSURE Operational Operational Local Panel 2L381 0027D (typical for each SG)

TD AFW PMP WBN2HS 212 TRIP/THV 2FCV Operational Operational junction box 2238 TDAFWP Room 0460056BS 151 POS CNTL Page A21

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State Pressure Switch to open U2 AOV 2FCV36386 from AFW WBN2PS 213 Supply Tank Operational Operational 0020321 upon low pressure in U1 Condensate supply piping.

Solenoid valve to open AFW WBN1, 2FSV 214 Supply Tank Operational Operational 0036386 insolation Valve 1,2 FCV36386 WBN1FT63 Safety Injection FT63151 on rack L655 215 Operational Operational 151 Pump Flow (refer to M6 for FI63151)

WBN2FT63 Safety Injection FT6320 on rack L472 216 Operational Operational 20 Pump Flow (refer to M6 for FI6320)

MAIN STEAM LOOP 4 WBN1PI001 Typical for each steam generator.

217 PRESSURE Operational Operational 0027D Local Panel L381, ESEL # 247 and 248.

(typical for each SG)

TD AFW PMP WBN1HS 218 TRIP/THV 1FCV Operational Operational junction box 2238 TDAFWP Room 0460056BS 151 POS CNTL Fuel Oil XFR WBN0SW Pump 219 3600103C, Standby Operational Disconnect 203C Switch Page A22

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State 220 Not used WBN0PMP Fuel Oil System 221 Standby Operational 360103, 203 Transfer Pump Level Indicating Transmitter for WBN0LIT the AFW Supply 222 Operational Operational Yard AFW Supply Tank Valve Vault 003227 Tank and High/Low Level Alarms Primary Cntrl WBN0FU1 223 Fuse for Fuel Oil Standby Operational 0SW3600003A/1 3600103A Pump A Starter Secondary Cntrl WBN0FU1 224 Fuse for Fuel Oil Standby Operational 0SW3600003A/1 3600103B Pump A Starter Primary Cntrl WBN0FU1 225 Fuse for Fuel Oil Standby Operational 0SW3600003A/1 3600103C Pump A Starter 480 V FLEX Main WBN0FUDS 226 Panel A Main Standby Operational PNL360FP/A 360FP/AM Disconnect 480 v FLEX Main WBN0FUDS 227 Panel B Main Standby Operational PNL360FP/B 360FP/BM Disconnect 480v AC Vital WBN0XSW 228 Transfer Switch Operational Operational 2360004S IV Page A23

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State 480v AC Vital WBN0XSW 229 Transfer Switch Operational Operational 2360003S III WBN0XSW 480v AC Vital 230 Operational Operational 2360002S Transfer Switch II WBN0XSW 480v AC Vital 231 Operational Operational 2360001S Transfer Switch I 480 V FLEX DG WBN0GNGC Neutral 232 Standby Operational 360DG/A, B Grounding Resistor Box WBN0BKR 480 V FLEX DG 233 Standby Operational 360DG/A, B Circuit Breaker Hydrogen WBN1HTR 234 Igniters Group A Operational Operational 1SI2681A lists locations of igniters 268various 34 igniters Hydrogen WBN2HTR 235 Igniters Group B Operational Operational 2SI2681B lists locations of igniters 268various 34 igniters Conservation WBN0RFV vent valve for 236 Operational Operational 0030005 the AFW Supply Tank.

TD Aux WBN1FCV 237 Feedwater Pmp Operational Operational 0010052 Governor Valve TD Aux WBN2FCV 238 Feedwater Pmp Operational Operational 0010052 Governor Valve Page A24

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State Pressure WBN0PI003 239 indicator for the Operational Operational Yard AFW Supply Tank Valve Vault 1

AFW Supply Tank Pressure Switch to open U1 AOV 1FCV36386 from AFW WBN1PS 240 Supply Tank Operational Operational 0020320 upon low pressure in U1 Condensate supply piping.

3MW Diesel 3A Primary U1, 3B Primary U2 OIP Figure A324 and WBN0BD 241 Generator 6.9KV Standby Operational 26.

3600003A, 3B Switchgear 3A Primary U1 and U2 OIP figure A325.

Hydrogen WBN2DXF 242 Mitigation Operational Operational C&A VT BD 2B1B, ESEL # 54 2680002B Transformer Hydrogen WBN1DXF 243 Mitigation Operational Operational C&A VT BD 1A1A, ESEL # 53 2680001A Transformer WBN0DXF 480 V FLEX DG 2 244 360DG/AP, KVA Sealed Standby Operational BP XFMR 6900V 3MW WBN0XFMR FLEX Diesel GEN 245 3603A/1, Standby Operational 20 KVA Dry Type 3B/1 Transformer Page A25

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State 6900V 3MW WBN0XFMR FLEX Diesel GEN 246 3603A/2, Standby Operational 5 KVA Dry Type 3B/2 Transformer WBN1PNL TDAFWP Control 247 Operational Operational 276L381 Panel WBN2PNL TDAFWP Control 248 Operational Operational 276L381 Panel Fuel Oil Transfer WBN0PNL 249 Pump Control Standby Operational 360DG/A, B1 Panel 125V Vital Batt WBN0XSW CHGR I 480 V 250 Standby Operational OIP Figure A322 2360001AS FLEX Transfer Switch 125V Vital Batt WBN0XSW CHGR 2 480 V 251 Standby Operational OIP Figure A322 2360002AS FLEX Transfer Switch 125V Vital Batt WBN0XSW CHGR 3 480 V 252 Standby Operational OIP Figure A322 2360003AS FLEX Transfer Switch 125V Vital Batt WBN0XSW CHGR 4 480 V 253 Standby Operational OIP Figure A322 2360004AS FLEX Transfer Switch WBN0PNL 480 V FLEX Fuse 254 Standby Operational OIP Figure A322 360FP/A Panel A Page A26

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN0PNL 480 V FLEX Fuse 255 Standby Operational OIP Figure A322 360FP/B Panel B AUX FW WBN1PNL 256 TURBINE SPEED Operational Operational 276L326S CONTROL PANEL AUX FW WBN2PNL 257 TURBINE SPEED Operational Operational 276L326S CONTROL PANEL 3MW Diesel Generator WBN0RES 258 Neutral Standby Operational 360003A, 3B Grounding Resistor WBN1PNL AUX FEEDWATER 259 Operational Operational 276L381A CONTROL WBN2PNL AUX FEEDWATER 260 Operational Operational 276L381A CONTROL FLEX COMMON WBN0XSW SPARE HP PUMP 261 Standby Operational 360HPCS TRANSFER SWITCH DG 1AA Transfer Kirkkey, EDG XFSW 1AA WBN1XSW 262 Switch TO 6.9KV Operational Operational Primary Path OIP Figure A324, 25, 26 82A SD BD 1AA Walkdown ID for this UNID is WBN1XSW82A/2A DG 2AA Transfer Kirkkey, EDG XSW 2AA WBN2XSW 263 Switch TO 6.9KV Operational Operational Primary Path OIP Figure A325 82A SD BD 2AA Walkdown ID for this UNID is WBN2XSW82A/2A Page A27

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State DG 1BB Transfer WBN1XSW 264 SwitchDG CS to Operational Operational Kirkkey 82B SD BD 1BB DG 2BB Transfer WBN2XSW Kirkkey, EDG XFSW 2BB 265 SwitchDG CS to Operational Operational 82B Primary Path OIP Figure A325 and 26 SD BD 2BB 480 V FLEX DG WBN0FUDS Pump 266 360DG/AP2, Standby Operational Disconnect BP2 Switch 3MW FLEX Diesel WBN0STR 267 GEN PMP Standby Operational 3600103, 203 Starter 6900V 3MW WBN0SW FLEX Diesel GEN 268 3600003A/1, Fused Standby Operational 3B/1 Disconnect Switch Reactor Level WBN1TE 269 Cap tube Temp Operational Operational Common Q Train B Unit 2 0680380E Comp Reactor Vessel WBN2PNL 270 instrumentation Operational Operational 276L340 System II Panel Reactor Vessel WBN1PNL 271 instrumentation Operational Operational 276L388 System I Panel Reactor Level WBN2TE 272 Cap tube Temp Operational Operational Common Q Train B Unit 2 0680380E Comp Page A28

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN0LI3 AFW Supply Tank 273 Operational Operational 227 Level Indicator WBN1LI63 LT6351 on rack L435 274 RWST Level Operational Operational 51 (refer to M6 for LI6351)

WBN2LI63 LT6351 on rack L435 275 RWST Level Operational Operational 51 (refer to M6 for LI6351)

WBN1LPF3 TDAFW Pump FT3142 on rack L656 276 Operational Operational 142 Flow (refer to M4 for FI3142)

WBN2LPF3 TDAFW Pump FT3142 on rack L215 277 Operational Operational 142 Flow (refer to M4 for FI3142)

WBN1LPF3 FT3147 on rack L341 278 AFW Flow S/G 3 Operational Operational 147B (refer to M3 for FI3147)

WBN2LPF3 FT3147 on rack L912 279 AFW Flow S/G 3 Operational Operational 147B (refer to M3 for FI3147)

WBN1LPF3 FT3155 on rack L217 280 AFW Flow S/G 2 Operational Operational 155A (refer to M3 for FI3155)

WBN2LPF3 FT3155 on rack L193 281 AFW Flow S/G 2 Operational Operational 155A (refer to M3 for FI3155)

WBN1LPF3 FT3163 on rack L654 282 AFW Flow S/G 1 Operational Operational 163B (refer to M3 for FI3163)

WBN2LPF3 FT3163 on rack L654 283 AFW Flow S/G 1 Operational Operational 163B (refer to M3 for FI3163)

WBN1LPF3 FT3170 on rack L216 284 AFW Flow S/G 4 Operational Operational 170A (refer to M3 for FI3170)

WBN2LPF3 FT3170 on rack L216 285 AFW Flow S/G 4 Operational Operational 170A (refer to M3 for FI3170)

WBN1LPL3 S/G WR Level LT3111 on rack L183 286 Operational Operational 111 Loop 4 (refer to M4 for LI3111)

Page A29

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2LPL3 S/G WR Level LT3111 on rack L183 287 Operational Operational 111 Loop 4 (refer to M4 for LI3111)

WBN1LPL3 S/G NR Level LT3148 on rack L182 288 Operational Operational 148 Loop 3 (refer to M3 for LI3148)

WBN2LPL3 S/G NR Level LT3148 on rack L182 289 Operational Operational 148 Loop 3 (refer to M3 for LI3148)

WBN1LPL3 S/G NR Level LT3156 on rack L597 290 Operational Operational 156 Loop 2 (refer to M3 for LI3148)

WBN2LPL3 S/G NR Level LT3156 on rack L597 291 Operational Operational 156 Loop 2 (refer to M3 for LI3148)

WBN1LPL3 S/G NR Level LT3164 on rack L183 292 Operational Operational 164 Loop 1 (refer to M3 for LI3164)

WBN2LPL3 S/G NR Level LT3164 on rack L183 293 Operational Operational 164 Loop 1 (refer to M3 for LI3164)

WBN1LPL3 S/G NR Level LT3171 on rack L183 294 Operational Operational 171 Loop 4 (refer to M3 for LI3171)

WBN2LPL3 S/G NR Level LT3171 on rack L183 295 Operational Operational 171 Loop 4 (refer to M3 for LI3171)

WBN1LPL3 S/G WR Level LT343 on rack L183 296 Operational Operational 43 Loop 1 (refer to M4 for LI343)

WBN2LPL3 S/G WR Level LT343 on rack L183 297 Operational Operational 43 Loop 1 (refer to M4 for LI343)

WBN1LPL3 S/G WR Level LT356 on rack L182 298 Operational Operational 56 Loop 1 (refer to M4 for LI356)

WBN2LPL3 S/G WR Level LT356 on rack L182 299 Operational Operational 56 Loop 2 (refer to M4 for LI356)

WBN1LPL3 S/G WR Level LT398 on rack L182 300 Operational Operational 98 Loop 3 (refer to M4 for LI398)

Page A30

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN2LPL3 S/G WR Level LT398 on rack L182 301 Operational Operational 98 Loop 3 (refer to M4 for LI398)

WBN1LPL 302 PZR Level Operational Operational LT68335 on rack L660(refer to M4 for LI68335) 68335 WBN2LPL LT68335 on rack L660 303 PZR Level Operational Operational 68335 (refer to M4 for LI68335)

WBN0LPL LT7842 on rack L945 304 SFP Level Operational Operational 7842 (refer to 2M10 for LI7842)

WBN1LPN detector through amplifier and optical isolator 305 Nuclear Flux Operational Operational 92131 to indicator on M13 WBN2LPN detector through amplifier and optical isolator 306 Nuclear Flux Operational Operational 92132 to indicator on M13 WBN1LPP1 S/G Pressure PT120 on rack L194 307 Operational Operational 20A Loop 3 (refer to M4 for PI120)

WBN2LPP1 S/G Pressure PT120 on rack L194 308 Operational Operational 20A Loop 3 (refer to M4 for PI120)

WBN1LPP1 S/G Pressure PT127 on rack L700 309 Operational Operational 27B Loop 4 (refer to M4 for PI127)

WBN2LPP1 S/G Pressure PT127 on rack L196 310 Operational Operational 27B Loop 4 (refer to M4 for PI127)

WBN1LPP1 S/G Pressure PT12 on rack L196 311 Operational Operational 2A Loop 1 (refer to M4 for PI12)

WBN2LPP1 S/G Pressure PT12 on rack L196 312 Operational Operational 2A Loop 1 (refer to M4 for PI12)

WBN1LPP1 S/G Pressure PT19 on rack L697 313 Operational Operational 9A Loop 2 (refer to M4 for PI19)

WBN2LPP1 S/G Pressure PT19 on rack L194 314 Operational Operational 9A Loop 2 (refer to M4 for PI19)

Page A31

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN1LPP PT6868 on rack L384 315 RCS WR Pressure Operational Operational 6868 (refer to M6 for PT6868)

WBN2LPP PT6866 on rack L360 316 RCS WR Pressure Operational Operational 6866 (refer to M6 for PT6866A)

WBN1LPPD Containment PT30310 on rack L188 317 Operational Operational 30310 Pressure (refer to M9 for PI30310)

WBN2LPPD Containment PT30310 on rack L188 318 Operational Operational 30310 Pressure (refer to M9 for PI30310)

WBN1LPT Containment PNLR143 319 Operational Operational 301032 Temperature (refer to M6 for TI301032)

WBN2LPT Containment PNLR143 320 Operational Operational 301032 Temperature (refer to M6 for TI301032)

WBN1LPT RCS WR Thot PNL099R2 321 Operational Operational 681 Loop 1 (refer to M5 for TI681)

WBN2LPT RCS WR Thot PNL099R2 322 Operational Operational 681 Loop 1 (refer to M5 for TI681)

WBN1LPT RCS WR Tcold PNL099R2 323 Operational Operational 6818 Loop 1 (refer to M5 for TI6818)

WBN2LPT RCS WR Tcold PNL099R2 324 Operational Operational 6818 Loop 1 (refer to M5 for TI6818)

WBN1LPT RCS WR Tcold PNL099R2 325 Operational Operational 6841 Loop 2 (refer to M5 for TI6841)

WBN2LPT RCS WR Tcold PNL099R2 326 Operational Operational 6841 Loop 2 (refer to M5 for TI6841)

WBN1LPT RCS WR Tcold PNL099R6 327 Operational Operational 6860 Loop 3 (refer to M5 for TI6860)

WBN2LPT RCS WR Tcold PNL099R6 328 Operational Operational 6860 Loop 3 (refer to M5 for TI6860)

Page A32

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN1LPT RCS WR Tcold PNL099R6 329 Operational Operational 6883 Loop 4 (refer to M5 for TI6883)

WBN2LPT RCS WR Tcold PNL099R6 330 Operational Operational 6883 Loop 4 (refer to M5 for TI6883)

PORV AND AFW WBN1PNL 331 LCV STM GEN 3 Operational Operational FLEX Nitrogen Control Station 276L1000

& 4 PNL PORV AND AFW WBN2PNL 332 LCV STM GEN 3 Operational Operational FLEX Nitrogen Control Station 276L1000

& 4 PNL PORV AND AFW WBN1PNL 333 LCV STM GEN 1 Operational Operational FLEX Nitrogen Control Station 276L1001

& 2 PNL PORV AND AFW WBN2PNL 334 LCV STM GEN 1 Operational Operational FLEX Nitrogen Control Station 276L1001

& 2 PNL Incore WBN1PNL 335 Thermocouple ICCM Train A Unit 1 0940008AJ Mon Sys Jbox Incore WBN1PNL 336 Thermocouple ICCM Train B Unit 1 0940008BJ Mon Sys Jbox WBN0DPL 480Volt 337 3600003A/1, Distribution Standby Operational 3B/1 Panel WBN0DPL 120/240 VAC 338 3600003A/2, Standby Operational Panel board 3B/2 Page A33

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State Hydrogen WBN2DPL Mitigation 339 Operational Operational 2680002B Distribution Panel Hydrogen WBN1DPL Mitigation 340 Operational Operational 2680001A Distribution Panel WBN0FUSD 480 V FLEX DG 341 360DG/AP1, Pump Fusible Standby Operational BP1 Disc Switch WBN0DG 480V FLEX/ESBO DG A Primary to Battery Boards 1 and 3 342 360000A, 225 KVA Diesel Standby Operational DG B Primary to Battery Boards 2 and 4; OIP fig A322.

000B Generator 6900V 3MW WBN0DG 3A Primary U1, 3B Primary U2 OIP Figure A324, 26.

343 Diesel Generator Standby Operational 3600003A, 3B 3A primary U1 and U2 OIP Figure A325.

TD Aux WBN1PMP 344 Feedwater Pump Operational Operational Automatic start on LOOP 0030001AS 1AS TD Aux WBN2PMP 345 Feedwater Pump Operational Operational Automatic start on LOOP 0030002AS 2AS WBN0PMP Fuel Oil Transfer 346 Standby Operational 360DG/A1, B1 Pump WBN1PMP 347 HP FLEX Pump Standby Operational OIP Figure A323.

360HP01 WBN2PMP 348 HP FLEX Pump Standby Operational OIP Figure A323.

360HP01 Page A34

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN1PMP 349 FLEX IP PUMP 01 Standby Operational OIP Figure A34, A323.

360IP01 WBN2PMP 350 FLEX IP PUMP 01 Standby Operational OIP Figure A34, A323 360IP01 WBN1PMP OIP Figure A311, Mode 5 & 6 RCS Makeup.

351 FLEX IP PUMP 02 Standby Operational 360IP02 OIP Figure A323 WBN2PMP OIP Figure A311. Mode 5 & 6 RCS Makeup 352 FLEX IP PUMP 02 Standby Operational 360IP02 OIP Figure A323.

FCV SHARED WBN1FCV AFW TANK 353 Closed Open 0036386 OUTLET PIPE TO U1 CONDENSATE FCV FOR AFW WBN2FCV Supply Tank 354 Closed Open 0036386 Outlet Piping to U2 Condensate SFP HEAT WBN0FCV Boundary Valve for Flow path to support SIP 355 EXCHANGER B Operational Operational 0700194B lube oil cooler CCS SUPPLY SFP HEAT WBN0FCV Boundary Valve for Flow path to support SIP lube oil 356 EXCHANGER A Operational Operational 0700197A cooler CCS SUPPLY Sta Ser & Cntl Air WBN0FCV FSI5.05 Appendix A 357 Cmpr Supply Hdr Open Closed 0670205 align ERCW header A Isol valve Page A35

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State Sta Ser & Cntl Air WBN0FCV FSI5.05 Appendix A 358 Cmpr Supply Hdr Open Closed 0670208 align ERCW header B Isol valve TD Aux WBN1FCV Feedwater Pmp 359 Operational Operational normal power supply: 125V Vital Battery Board III 001051 Trip & Throttle Valve TD Aux WBN2FCV Feedwater Pmp 360 Operational Operational normal power supply: 125V Vital Battery Board I 001051 Trip & Throttle Valve ERCW Header B WBN2FCV switchover to ERCW header. 480V RMOV BD 2B2B 361 TD AFW PMP Operational Operational 0030179AB or handwheel SUCT (PS144)

ERCW Header A WBN2FCV switchover to ERCW header. 480V RMOV BD 2A2A 362 TD AFW PMP Operational Operational 0030136AA or handwheel SUCT (PS139)

ERCW Header A WBN2FCV switchover to ERCW header. 480V RMOV BD 2A2A 363 TD AFW PMP Operational Operational 0030136BA or handwheel SUCT ERCW Header B WBN2FCV switchover to ERCW header. 480V RMOV BD 2B2B 364 TD AFW PMP Operational Operational 0030179BB or handwheel SUCT ERCW Header A WBN1FCV switchover to ERCW header. 480V RMOV BD 1A2A 365 TD AFW PMP Operational Operational 0030136AA or handwheel SUCT (PS139)

ERCW Header A WBN1FCV switchover to ERCW header. 480V RMOV BD 1A2A 366 TD AFW PMP Operational Operational 0030136BA or handwheel SUCT Page A36

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State ERCW Header B WBN1FCV switchover to ERCW header. 480V RMOV BD 1B2B 367 TD AFW PMP Operational Operational 0030179AB or handwheel SUCT (PS144)

ERCW Header B WBN1FCV switchover to ERCW header. 480V RMOV BD 1B2B 368 TD AFW PMP Operational Operational 0030179BB or handwheel SUCT Admin WBN1FCV CCS HX C SUP FSI5.05 Appendix A 369 locked Open 0670147A FROM HDR 1A align ERCW header closed Admin WBN1FCV CCS HX C SUP FSI5.05 Appendix A 370 locked Open 0670458A FROM HDR 1B align ERCW header closed N2 TANK NO. 1 WBN1TANK 371 SUPPLY TO 1 Operational Operational 30402A LCV0030173B N2 TANK NO. 1 WBN1TANK 372 SUP TO 1PCV Operational Operational 0010405A 0010012B N2 TANK NO. 1 WBN2TANK 373 SUP TO 2PCV Operational Operational 0010405A 0010012B N2 TANK NO. 2 WBN1TANK 374 SUP TO 1PCV Operational Operational 0010405B 0010012B N2 TANK NO. 2 WBN2TANK 375 SUP TO 2PCV Operational Operational 0010405B 0010012B N2 TANK NO. 1 WBN1TANK 376 SUP TO 1PCV Operational Operational 0010406A 0010030B Page A37

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State N2 TANK NO. 1 WBN2TANK 377 SUP TO 2PCV Operational Operational 0010406A 0010030B N2 TANK NO. 2 WBN1TANK 378 SUP TO 1PCV Operational Operational 0010406B 0010030B N2 TANK NO. 2 WBN2TANK 379 SUP TO 2PCV Operational Operational 0010406B 0010030B N2 TANK NO. 1 WBN1TANK 380 SUP TO 1PCV Operational Operational 0010407A 0010023A N2 TANK NO. 1 WBN2TANK 381 SUP TO 2PCV1 Operational Operational 0010407A 0023A N2 TANK NO. 2 WBN1TANK 382 SUP TO 1PCV Operational Operational 0010407B 0010023A N2 TANK NO. 2 WBN2TANK 383 SUP TO 2PCV1 Operational Operational 0010407B 0023A N2 TANK NO. 1 WBN1TANK 384 SUP TO 1PCV Operational Operational 0010408A 0010005A N2 TANK NO. 1 WBN2TANK 385 SUP TO 2PCV Operational Operational 0010408A 0010005A N2 TANK NO. 2 WBN1TANK 386 SUP TO 1PCV Operational Operational 0010408B 0010005A Page A38

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State N2 TANK NO. 1 WBN2TANK 387 SUP TO 2PCV Operational Operational 0010408B 0010005A N2 TANK NO. 1 WBN2TANK 388 SUPPLY TO 2 Operational Operational 30402A LCV0030173B N2 TANK NO. 2 WBN1TANK 389 SUPPLY TO 1 Operational Operational 30402B LCV0030173B N2 TANK NO. 2 WBN2TANK 390 SUPPLY TO 2 Operational Operational 30402B LCV0030173B N2 TANK NO. 1 WBN1TANK 391 SUPPLY TO 1 Operational Operational 30402C LCV0030174B N2 TANK NO. 1 WBN2TANK 392 SUPPLY TO 2 Operational Operational 30402C LCV0030174B N2 TANK NO. 2 WBN1TANK 393 SUPPLY TO 1 Operational Operational 30402D LCV0030174B N2 TANK NO. 2 WBN2TANK 394 SUPPLY TO 2 Operational Operational 30402D LCV0030174B N2 TANK NO. 1 WBN1TANK 395 SUP TO 1LCV Operational Operational 30403A 0030172A N2 TANK NO. 1 WBN2TANK 396 SUP TO 2LCV3 Operational Operational 30403A 172A Page A39

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State N2 TANK NO. 2 WBN1TANK 397 SUP TO 1LCV Operational Operational 30403B 003172A N2 TANK NO. 2 WBN2TANK 398 SUP TO 2LCV3 Operational Operational 30403B 172A N2 TANK NO. 1 WBN1TANK 399 SUP TO 1LCV Operational Operational 30403C 0030175A N2 TANK NO. 1 WBN2TANK 400 SUP TO 2LCV3 Operational Operational 30403C 175A N2 TANK NO. 2 WBN1TANK 401 SUP TO 1LCV Operational Operational 30403D 0030175A N2 TANK NO. 2 WBN2TANK 402 SUP TO 2LCV3 Operational Operational 30403D 175A WBN0TANK AFW Supply Tank 403 Operational Operational 0030226 500,000 gallons 6900V 3MW WBN0TANK 404 FLEX DG Fuel Oil Standby Operational 360113, 213 Storage Tank WBN1CLR TD Aux FW PMP 405 Operational Operational 0030001B Oil Cooler WBN2CLR TD Aux FW PMP 406 Operational Operational 0030001B Oil Cooler WBN2RLY Transfer Sw in 407 Operational Operational 0460057S Aux Pos Isol Rly T351/TycoPotter & Brumfield Page A40

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State B21 Relay AFPT WBN2RLY 408 Trip & Throttle Operational Operational 046B002/1S Vlv Photo Iso Struthers Dunn B22 Relay AFPT WBN2RLY 409 Trip & Throttle Operational Operational 046B002/2S Vlv Photo Iso Struthers Dunn B23 Relay AFPT WBN2RLY 410 Speed Control Operational Operational 046B002/3S Instr Pwr P297/Potter & Brumfield BA & BB Relay WBN2RLY AFPT Speed 411 Operational Operational 046BAS Control Buffer Relay A160/AllenBradley Co.

BA1 Relay AFPT WBN2RLY 412 Speed Control Operational Operational 046BA1S Buffer A160/AllenBradley Co.

BA & BB Relay WBN2RLY AFPT Speed 413 Operational Operational 046BBS Control Buffer Relay A160/AllenBradley Co.

WBN2RLY Aux FW Pump 414 Operational Operational 046R/AA Vlv Sep Relay W120/Westinghouse Elec Corp.

WBN2RLY Aux FW Pump 415 Operational Operational 046R/BB Vlv Sep Relay W120/Westinghouse Elec Corp.

WBN2RLY AFPT ACC Reset 416 Operational Operational 046R1S Relay A160/AllenBradley Co.

WBN2RLY AFPT ACC Reset 417 Operational Operational 046R2S Relay A160/AllenBradley Co.

Page A41

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State AFPT SUP Xfer WBN2RLY FCV115,16 &

418 Operational Operational 046R4A 51 Sep Relay TR A AllenBradley Co.

Aux Feed Pump WBN2RLY Trb Stm Supply 419 Operational Operational 046R5A Xfer Sep Relay TR A Agastat Turb/Mtr Driven WBN2RLY 420 Aux FW Pump Operational Operational 046RA1A Vlvs Aux Relay W120/Westinghouse Elec Corp.

Turb/Mtr Driven WBN2RLY 421 Aux FW Pump Operational Operational 046RA2A Vlv SSEP Relay W120/Westinghouse Elec Corp.

AFPT Pump 2 WBN2RLY FCV151 Mtr Dr 422 Operational Operational 046RASS Vlv 2LCV3156

& 164 W120/Westinghouse Elec Corp.

Turb/Mtr Driven WBN2RLY 423 Aux FW Pump Operational Operational 046RB1B Vlvs Aux Relay W120/Westinghouse Elec Corp.

Turb Driven Aux WBN2RLY 424 FW Pump Vlv Operational Operational 046RB2B SEP Relay W120/Westinghouse Elec Corp.

AFPT Pump 2 WBN2RLY FCV151 Mtr Dr 425 Operational Operational 046RBSS Vlv 2LCV3171

& 148 W120/Westinghouse Elec Corp.

Page A42

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State AFPT SUP Xfer WBN2RLY 426 FCV115,16 & Operational Operational 046SSTS 51 Sep Relay A160/AllenBradley Co.

WBN1RLY Transfer Sw in 427 Operational Operational 0460057S Aux Pos Isol Rly T351/TycoPotter & Brumfield B21 Relay AFPT WBN1RLY 428 Trip & Throttle Operational Operational 046B002/1S Vlv Photo Iso Struthers Dunn B22 Relay AFPT WBN1RLY 429 Trip & Throttle Operational Operational 046B002/2S Vlv Photo Iso Struthers Dunn B23 Relay AFPT WBN1RLY 430 Speed Control Operational Operational 046B002/3S Instr Pwr P297/Potter & Brumfield BA & BB Relay WBN1RLY AFPT Speed 431 Operational Operational 046BAS Control Buffer Relay A160/AllenBradley Co.

BA1 Relay AFPT WBN1RLY 432 Speed Control Operational Operational 046BA1S Buffer A160/AllenBradley Co.

BA & BB Relay WBN1RLY AFPT Speed 433 Operational Operational 046BBS Control Buffer Relay A160/AllenBradley Co.

WBN1RLY Aux FW Pump 434 Operational Operational 046R/AA Vlv Sep Relay W120/Westinghouse Elec Corp.

WBN1RLY Aux FW Pump 435 Operational Operational 046R/BB Vlv Sep Relay W120/Westinghouse Elec Corp.

Page A43

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State WBN1RLY AFPT ACC Reset 436 Operational Operational 046R1S Relay A160/AllenBradley Co.

WBN1RLY AFPT ACC Reset 437 Operational Operational 046R2S Relay A160/AllenBradley Co.

AFPT SUP Xfer WBN1RLY FCV115,16 &

438 Operational Operational 046R4A 51 Sep Relay TR A AllenBradley Co.

Aux Feed Pump WBN1RLY Trb Stm Supply 439 Operational Operational 046R5A Xfer Sep Relay TR A Agastat Turb/Mtr Driven WBN1RLY 440 Aux FW Pump Operational Operational 046RA1A Vlvs Aux Relay W120/Westinghouse Elec Corp.

Turb/Mtr Driven WBN1RLY 441 Aux FW Pump Operational Operational 046RA2A Vlv SSEP Relay W120/Westinghouse Elec Corp.

AFPT Pump 2 WBN1RLY FCV151 Mtr Dr 442 Operational Operational 046RASS Vlv 2LCV3156

& 164 W120/Westinghouse Elec Corp.

Turb/Mtr Driven WBN1RLY 443 Aux FW Pump Operational Operational 046RB1B Vlvs Aux Relay W120/Westinghouse Elec Corp.

Turb Driven Aux WBN1RLY 444 FW Pump Vlv Operational Operational 046RB2B SEP Relay W120/Westinghouse Elec Corp.

Page A44

Watts Bar Nuclear Plant ESEP Report ESEL Equipment State Item UNID Description Normal Desired Notes/Comments

1. State State AFPT Pump 2 WBN1RLY FCV151 Mtr Dr 445 Operational Operational 046RBSS Vlv 2LCV3171

& 148 W120/Westinghouse Elec Corp.

AFPT SUP Xfer WBN1RLY 446 FCV115,16 & Operational Operational 046SSTS 51 Sep Relay A160/AllenBradley Co.

TDAFW WBN1STR 447 Trip/Throttle Operational Operational 0460056AS Motor Starter TDAFW WBN2STR 448 Trip/Throttle Operational Operational 0460056AS Motor Starter WBN1FSV Reactor Vessel Operational Operational 125v DC Vital Battery Bd I 449 0680394 Head Vent Isol 450 WBN1FSV RV HV Throttle Operational Operational 125v DC Vital Battery Bd I 0680397 Valve 451 WBN2FSV RV HV Isolation Operational Operational 125v DC Vital Battery Bd II 0680395 Valve 452 WBN2FSV RV HV Throttle Operational Operational 125v DC Vital Battery Bd II 0680396 Valve Page A45

Watts Bar Nuclear Plant ESEP Report ATTACHMENT B ESEP HCLPF VALUES AND FAILURE MODES TABULATION FOR WATTS BAR NUCLEAR PLANT Page B1

Watts Bar Nuclear Plant ESEP Report Table B1: ESEP HCLPF VALUES AND FAILURE MODES FOR WATTS BAR NUCLEAR PLANT Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 Solid State 1 PNL099 Protection System Screened > 0.5 R48A Train A WBN2 Solid State 2 PNL099 Protection System Screened > 0.5 R50B Train B WBN2 Reactor 3 PNL099 Protection I Screened > 0.5 R2D Process System WBN2 Solid State 4 PNL099 Protection System Screened > 0.5 R48A Train A WBN1 Solid State 5 PNL099 Protection System Screened > 0.5 R50B Train B WBN2 Reactor 6 PNL099 Protection II Screened > 0.5 R6E Process System WBN1 ICCM System 7 PNL275 Screened > 0.5 Train A CH 1 R179A WBN2 Common Q PAMS 8 PNL275 Screened > 0.5 Panel Train A R179A WBN1 ICCM System 9 PNL275 Screened > 0.5 Train B CH 2 R180B WBN2 Common Q PAMS 10 PNL275 Screened > 0.5 Panel Train B R180B WBN2 RX HEAD VENT 11 HIC068 Screened > 0.5 FLOW CONTROL 396 WBN2 Solid State 12 PNL099 Protection System Screened > 0.5 R46A Train A WBN2 Solid State 13 PNL099 Protection System Screened > 0.5 R49B Train B Page B2

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 Reactor 14 PNL099 Protection II Screened > 0.5 R6E Process System WBN1 SIS Accumulator 15 ACUM Screened > 0.5 Tank 1 0630001 WBN1 SIS Accumulator 16 ACUM Screened > 0.5 Tank 2 0630002 WBN1 SIS Accumulator 17 ACUM Screened > 0.5 Tank 3 0630003 WBN1 SIS Accumulator 18 ACUM Screened > 0.5 Tank 4 0630004 WBN0 125 V Vital 19 BAT236 Screened > 0.5 Battery I 0001D WBN0 125 V Vital 20 BAT236 Screened > 0.5 Battery II 0002E WBN0 125 V Vital 21 BAT236 Screened > 0.5 Battery III 0003F WBN0 125 V Vital 22 BAT236 Screened > 0.5 Battery IV 0004G WBN1 6.9 KV shutdown 23 BD211 Screened > 0.5 Board 1AA AA WBN2 6.9 KV shutdown 24 BD211 Screened > 0.5 Board 2BB BB WBN1 480V Shutdown 25 BD212 Screened > 0.5 Board 1A1A A001A WBN2 480V Shutdown 26 BD212 Screened > 0.5 Board 2A1A A001A WBN1 480V Shutdown 27 BD212 Screened > 0.5 Board 1A2A A002A Page B3

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 480V Shutdown 28 BD212 Screened > 0.5 Board 2B2B B002B WBN0 125V Vital Battery 29 BD236 Screened > 0.5 Board I 0001D WBN0 125V Vital Battery 30 BD236 Screened > 0.5 Board II 0002E WBN0 125V Vital Battery 31 BD236 Screened > 0.5 Board III 0003F WBN0 125V Vital Battery 32 BD236 Screened > 0.5 Board IV 0004G WBN0 CHGR 125 V Vital 33 Screened > 0.5 236 Battery Charger I 0001D WBN0 CHGR 125 V Vital 34 Screened > 0.5 236 Battery Charger II 0002/E WBN0 CHGR 125 V Vital 35 Screened > 0.5 236 Battery Charger III 0003/F WBN0 125 V Vital CHGR 36 Battery Charger Screened > 0.5 236 IV 0004/G WBN1 CCS HEAT 37 HTX070 Screened > 0.5 EXCHANGER A 0185 WBN2 CCS HEAT 38 HTX070 Screened > 0.5 EXCHANGER B 0185 WBN1 RHR HEAT 39 HTX074 Screened > 0.5 EXCHANGER 1A 0030A Page B4

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 RHR HEAT 40 HTX074 Screened > 0.5 EXCHANGER 2A 0031A WBN1 120 V AC Vital 41 INV235 Screened > 0.5 Inverter 1I 0001D WBN2 120 V AC Vital 42 INV235 Screened > 0.5 Inverter 2I 0001D WBN1 120 V AC Vital 43 INV235 Screened > 0.5 Inverter 1II 0002E WBN2 120 V AC Vital 44 INV235 Screened > 0.5 Inverter 2II 0002E WBN1 120 V AC Vital 45 INV235 Screened > 0.5 Inverter 1III 0003F WBN2 120 V AC Vital 46 INV235 Screened > 0.5 Inverter 2III 0003F WBN1 120 V AC Vital 47 INV235 Screened > 0.5 Inverter 1IV 0004G WBN2 120 V AC Vital 48 INV235 Screened > 0.5 Inverter 2IV 0004G WBN1 MCC 480V Reactor 49 Screened > 0.5 213 MOV Board 1A1A A001A WBN2 MCC 480V Reactor 50 Screened > 0.5 213 MOV Board 2A1A A001A WBN1 MCC 480V Reactor 51 Screened > 0.5 213 MOV Board 1B1B B001B Page B5

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 MCC 480V Reactor 52 Screened > 0.5 213 MOV Board 2B1B B001B WBN1 Cont & Aux Bldg MCC 53 Vent Board 1A1 Screened > 0.5 214 A

A001A WBN2 MCC Cont & Aux Bldg 54 Screened > 0.5 214 Vent Board 2B1B B001B WBN1 Cont & Aux Bldg MCC 55 Vent Board 1A2 Screened > 0.5 214 A

A002A WBN2 MCC Cont & Aux Bldg 56 Screened > 0.5 214 Vent Board 2B2B B002B WBN1 480 V 57 OXF212 Transformer 1A1 Screened > 0.5 A001A A WBN2 480 V 58 OXF212 Transformer 2A1 Screened > 0.5 A001A A WBN1 480 V 59 OXF212 Transformer 1A2 Screened > 0.5 A002A A WBN2 480 V 60 OXF212 Transformer 2B2 Screened > 0.5 B002B B WBN1 Centrifugal PMP 61 Charging Pump Screened > 0.5 062 1AA 0108A WBN2 Centrifugal PMP 62 Charging Pump Screened > 0.5 062 2AA 0108A Page B6

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 SAFETY PMP 63 INJECTION PUMP Screened > 0.5 063 1AA 0010A WBN2 SAFETY PMP 64 INJECTION PUMP Screened > 0.5 063 2AA 0015A WBN1 Component PMP 65 Cooling System Screened > 0.5 070 Pump 1AA 0046A WBN2 Component PMP 66 Cooling System Screened > 0.5 070 Pump 2AA 0059A WBN1 PMP 67 RHR PUMP 1AA Screened > 0.5 074 0010A WBN2 PMP 68 RHR PUMP 2BB Screened > 0.5 074 0020B WBN1 Steam Generator 69 PNL276 Level Control Screened > 0.5 L011A Panel WBN2 Steam Generator 70 PNL276 Level Control Screened > 0.5 L011A Panel WBN1 Steam Generator 71 PNL276 Level Control Screened > 0.5 L011B Panel WBN2 Steam Generator 72 PNL276 Level Control Screened > 0.5 L011B Panel WBN1 UNIT CONT.

73 PNL278 Screened > 0.5 BOARD PNL 1M3 M003 WBN2 UNIT CONT.

74 PNL278 Screened > 0.5 BOARD PNL 2M3 M003 Page B7

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 UNIT CONT.

75 PNL278 Screened > 0.5 BOARD PNL 1M4 M004 WBN2 UNIT CONT.

76 PNL278 Screened > 0.5 BOARD PNL 2M4 M004 WBN1 TEMPERATURE 77 PNL278 Screened > 0.5 MONITORING M010 WBN2 TEMPERATURE 78 PNL278 Screened > 0.5 MONITORING M010 WBN1,2 TANK 7 Day Fuel Oil Sup 79 Screened > 0.5 018 Dsl Gen 0038, 41 WBN1 Refueling Water 80 TANK Screened > 0.5 Storage Tank 0630046 WBN2 Refueling Water 81 TANK Screened > 0.5 Storage Tank 0630046 WBN1 Component 82 TANK Cooling Water Screened > 0.5 0700001 Surge Tank WBN2 Component 83 TANK Cooling Water Screened > 0.5 0700001 Surge Tank WBN1 CVCS SEAL 84 FCV062 WATER RETURN Screened > 0.5 0063A HEADER ISOL WBN2 CVCS SEAL 85 FCV062 WATER RETURN Screened > 0.5 0063A HEADER ISOL WBN1 Accumulator 86 FCV063 Screened > 0.5 Isolation Valve 4 0067 WBN2 Accumulator 87 FCV063 Screened > 0.5 Isolation Valve 4 0067 Page B8

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 Accumulator 88 FCV063 Screened > 0.5 Isolation Valve 3 0080 WBN2 Accumulator 89 FCV063 Screened > 0.5 Isolation Valve 3 0080 WBN1 LWR CNTMT A 90 FCV067 Screened > 0.5 CLRS SUP CIV 0083 WBN1 Accumulator 91 FCV063 Screened > 0.5 Isolation Valve 2 0098 WBN2 Accumulator 92 FCV063 Screened > 0.5 Isolation Valve 2 0098 WBN1 Accumulator 93 FCV063 Screened > 0.5 Isolation Valve 1 0118 WBN2 Accumulator 94 FCV063 Screened > 0.5 Isolation Valve 1 0118 WBN2 LWR CNTMT A 95 FCV067 Screened > 0.5 CLRS SUP CIV 0083 WBN1 LWR CNTMT C 96 FCV067 Screened > 0.5 CLRS SUP CIV 0091 WBN2 LWR CNTMT C 97 FCV067 Screened > 0.5 CLRS SUP CIV 0091 WBN1 LWR CNTMT B 98 FCV067 Screened > 0.5 CLRS SUP CIV 0099 WBN2 LWR CNTMT B 99 FCV067 Screened > 0.5 CLRS SUP CIV 0099 WBN1 LWR CNTMT D 100 FCV067 Screened > 0.5 CLRS SUP CIV 0107 WBN2 LWR CNTMT D 101 FCV067 Screened > 0.5 CLRS SUP CIV 0107 Page B9

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 UPR CNTMT CLR 102 FCV067 Screened > 0.5 A SUP CIV 0130 WBN2 UPR CNTMT CLR 103 FCV067 Screened > 0.5 A SUP CIV 0130 WBN1 UPR CNTMT CLR C 104 FCV067 Screened > 0.5 SUP CIV 0133 WBN2 UPR CNTMT CLR C 105 FCV067 Screened > 0.5 SUP CIV 0133 WBN1 UPR CNTMT CLR B 106 FCV067 Screened > 0.5 SUP CIV 0138 WBN2 UPR CNTMT CLR B 107 FCV067 Screened > 0.5 SUP CIV 0138 WBN1 UPR CNTMT CLR 108 FCV067 Screened > 0.5 D SUP CIV 0141 WBN2 UPR CNTMT CLR 109 FCV067 Screened > 0.5 D SUP CIV 0141 WBN2 CCS HX DISCH to 110 FCV067 Screened > 0.5 HDR B 0143 WBN1 CCS HX DISCH to 111 FCV067 Screened > 0.5 HDR B 0143 WBN0 CCS HX C DISCH to 112 FCV067 Screened > 0.5 HDR A 0144 WBN2 PRESSURIZER 113 FCV068 PORV BLOCK Screened > 0.5 0332B VALVE WBN1 PRESSURIZER 114 FCV068 PORV BLOCK Screened > 0.5 0333 VALVE WBN1 RC Pump Therm 115 FCV070 Barrier Ret Screened > 0.5 0090A CNTNMT Isol Page B10

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 RC Pump Therm 116 FCV070 Barrier Ret Screened > 0.5 0090A CNTNMT Isol WBN1 RC Thermal 117 FCV070 Barrier Cont Isol Screened > 0.5 0133A Valve WBN2 RC Thermal 118 FCV070 Barrier Cont Isol Screened > 0.5 0133A Valve WBN2 TD AFW PUMP SG 119 LCV002 Screened > 0.5

1. 2 Level Control 0173B WBN1 TD AFW PUMP SG 120 LCV003 Screened > 0.5

1. 3 Level Control 0172A WBN2 TD AFW PUMP SG 121 LCV003 Screened > 0.5

1. 3 Level Control 0172A WBN1 TD AFW PUMP SG 122 LCV003 Screened > 0.5

1. 2 Level Control 0173B WBN1 TD AFW PUMP SG 123 LCV003 Screened > 0.5

1. 1 Level Control 0174B WBN2 TD AFW PUMP SG 124 LCV003 Screened > 0.5

1. 1 Level Control 0174B WBN1 TD AFW PUMP SG 125 LCV003 Screened > 0.5

1. 4 Level Control 0175A Page B11

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 TD AFW PUMP SG 126 LCV003 Screened > 0.5

1. 4 Level Control 0175A WBN1 SG 1Main STM 127 PCV001 HDR PWR Relief Screened > 0.5 0005T Control Valve WBN2 SG 1Main STM 128 PCV001 HDR PWR Relief Screened > 0.5 0005T Control Valve WBN1 SG 2 Main STM 129 PCV001 HDR PWR Relief Screened > 0.5 0012T Control Valve WBN2 SG 2 Main STM 130 PCV001 HDR PWR Relief Screened > 0.5 0012T Control Valve WBN1 SG 3 Main STM 131 PCV001 HDR PWR Relief Screened > 0.5 0023T Control Valve WBN2 SG 3 Main STM 132 PCV001 HDR PWR Relief Screened > 0.5 0023T Control Valve WBN1 SG 4Main STM 133 PCV001 HDR PWR Relief Screened > 0.5 0030T Control Valve WBN2 SG 4Main STM 134 PCV001 HDR PWR Relief Screened > 0.5 0030T Control Valve WBN2 PRESSURIZER 135 PCV068 Screened > 0.5 PORV 0334 WBN1 PRESSURIZER 136 PCV068 Screened > 0.5 PORV 0340A WBN1 Steam Generator 137 SFV001 #3 Main Steam Screened > 0.5 0512 Safety Valve WBN2 Steam Generator 138 SFV001 #3 Main Steam Screened > 0.5 0512 Safety Valve Page B12

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 Steam Generator 139 SFV001 #2 Main Steam Screened > 0.5 0517 Safety Valve WBN2 Steam Generator 140 SFV001 #2 Main Steam Screened > 0.5 0517 Safety Valve WBN1 Steam Generator 141 SFV001 #1 Main Steam Screened > 0.5 0522 Safety Valve WBN2 Steam Generator 142 SFV001 #1 Main Steam Screened > 0.5 0522 Safety Valve WBN1 Steam Generator 143 SFV001 #4 Main Steam Screened > 0.5 0527 Safety Valve WBN2 Steam Generator 144 SFV001 #4 Main Steam Screened > 0.5 0527 Safety Valve WBN1 Containment Air 145 FAN030 Screened > 0.5 Return Fan AA 0038 WBN2 Containment Air 146 FAN030 Screened > 0.5 Return Fan BB 0039 WBN1 AC OUTPUT 147 EI235 AMMETER Screened > 0.5 001/A1 INVERTER 1I WBN1 120 V AC Vital 148 BD235 Instrument Power Screened > 0.5 0001D Board 1I WBN1 AC OUTPUT 149 EI235 AMMETER Screened > 0.5 002/A1 INVERTER 1II WBN1 120 V AC Vital 150 BD235 Instrument Power Screened > 0.5 0002E Board 1II WBN1 120 V AC Vital 151 BD235 Instrument Power Screened > 0.5 0003F Board 1III WBN1 120 V AC Vital 152 BD235 Instrument Power Screened > 0.5 0004G Board 1IV Page B13

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 CCP 1AA LUBE 153 CLR062 Screened > 0.5 OIL COOLER 0108AA WBN1 CCP 1AA GEAR 154 CLR062 Screened > 0.5 OIL COOLER 0108BA SAFETY WBN1 INJECTION PUMP 155 CLR063 Screened > 0.5 1AA LUBE OIL 0010 COOLER WBN1 CNTMT SPRAY 156 CLR072 PUMP 1AA OIL Screened > 0.5 0027 COOLER WBN1 RHR PUMP 1AA 157 HTX074 SEAL WATER Screened > 0.5 0010A HEAT EXCHANGER WBN1 STM GEN #3 TRF 158 XS003 Screened > 0.5 SW 0172AA WBN1 STM GEN #4 TRF 159 XS003 Screened > 0.5 SW 0175AA WBN1 STM GEN #2 TRF 160 XS003 Screened > 0.5 SW 0173AB WBN1 STM GEN #1 TRF 161 XS003 Screened > 0.5 SW 0174AB WBN1 TURB AFWP 162 Screened > 0.5 XI04657 DEMAND WBN1 AUX FPT FLOW 163 FIC046 Screened > 0.5 IND CONTROLLER 0057AS TD AFW PMP Trip/Throttle WBN1 Valve Handswitch 164 HS046 Screened > 0.5 AUTO MAN 0056AS REMOTE SP FOR FIC4657B WBN1 AFWT AS 165 SI046 Screened > 0.5 SPEED 0056AS Page B14

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 AFWT AS 166 XI046 Screened > 0.5 MOP POSITION 0054A WBN1 167 XI068 Plasma Display Screened > 0.5 0100 WBN1 Plasma Display 168 XS068 Screened > 0.5 Key Pad 0101 WBN1 RCS PRZR PWR 169 HS068 Screened > 0.5 RELIEF VALVE 340AA WBN2 Common Q 170 CPU094 Operator Module Screened > 0.5 6000 Node Box WBN2 Common Q first 171 FOC094 Screened > 0.5 modem 4001A WBN1 RX HEAD VENT 172 HIC068 Screened > 0.5 FLOW CONTROL 397 WBN2 SIS PUMP AA 173 HS063 Screened > 0.5 MOTOR 0010A WBN1 SIS PUMP AA 174 HS063 Screened > 0.5 MOTOR 0010A WBN1 AIR RET FAN AA 175 HS030 Screened > 0.5 ON/OFF 0038A WBN2 AIR RET FAN BB 176 HS030 Screened > 0.5 ON/OFF 0039B WBN2 AC OUTPUT 177 EI235 AMMETER Screened > 0.5 001/A1 INVERTER 2I WBN2 120 V AC Vital 178 BD235 Instrument Power Screened > 0.5 0001D Board 2I WBN2 120 V AC Vital 179 BD235 Instrument Power Screened > 0.5 0002E Board 2II Page B15

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 AC OUTPUT 180 EI235 AMMETER Screened > 0.5 002/A1 INVERTER 2II WBN2 120 V AC Vital 181 BD235 Instrument Power Screened > 0.5 0003F Board 2III WBN2 120 V AC Vital 182 BD235 Instrument Power Screened > 0.5 0004G Board 2IV WBN2 CCP 2AA LUBE 183 CLR062 Screened > 0.5 OIL COOLER 0108AA WBN2 CCP 2AA GEAR 184 CLR062 Screened > 0.5 OIL COOLER 0108BA SAFETY WBN2 INJECTION PUMP 185 CLR063 Screened > 0.5 2AA LUBE OIL 0010 COOLER WBN2 CNTMT SPRAY 186 CLR072 PUMP 2AA OIL Screened > 0.5 0027 COOLER WBN2 RHR PUMP 2AA 187 HTX074 SEAL WATER Screened > 0.5 0010A HEAT EXCHANGER WBN2 STM GEN #3 TRF 188 XS003 Screened > 0.5 SW 0172AA WBN2 STM GEN #4 TRF 189 XS003 Screened > 0.5 SW 0175AA WBN2 STM GEN #2 TRF 190 XS003 Screened > 0.5 SW 0173AB WBN2 STM GEN #1 TRF 191 XS003 Screened > 0.5 SW 0174AB WBN2 TURB AFWP 192 Screened > 0.5 XI04657 DEMAND WBN2 AUX FPT FLOW 193 FIC046 Screened > 0.5 IND CONTROLLER 0057AS Page B16

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode TD AFW PMP Trip/Throttle WBN2 Valve Handswitch 194 HS046 Screened > 0.5 AUTO MAN 0056AS REMOTE SP FOR FIC4657B WBN2 AFWT AS 195 SI046 Screened > 0.5 SPEED 0056AS WBN2 AFWT AS 196 XI046 Screened > 0.5 MOP POSITION 0054A WBN2 RCS PRZR REL 197 HS068 Screened > 0.5 FLOW CONTROL 333A WBN2 RX HEAD VENT 198 HIC068 Screened > 0.5 FLOW CONTROL 397 WBN2 Plasma Touch 199 MON Screened > 0.5 Screen Display 0680110 WBN2 6.9 KV shutdown 200 Screened > 0.5 BD211A Board 2AA WBN2 SIS Accumulator 201 ACUM Screened > 0.5 Tank 1 0630001 WBN2 SIS Accumulator 202 ACUM Screened > 0.5 Tank 2 0630002 WBN2 SIS Accumulator 203 ACUM Screened > 0.5 Tank 3 0630003 WBN2 SIS Accumulator 204 ACUM Screened > 0.5 Tank 4 0630004 WBN1 RX HEAD VENT 205 HIC068 Screened > 0.5 FLOW CONTROL 396 WBN1 Reactor 206 PNL099 Protection I Screened > 0.5 R2D Process System Page B17

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 Solid State 207 PNL099 Protection System Screened > 0.5 R46A Train A WBN1 Solid State 208 PNL099 Protection System Screened > 0.5 R49B Train B WBN1 Reactor 209 PNL099 Protection II Screened > 0.5 R6E Process System WBN1 PMP Containment 210 Screened > 0.5 072 Spray Pump 1AA 0027A MAIN STEAM WBN2 LOOP 4 211 PI001 PRESSURE Anchorage 0.56 0027D (typical for each SG)

WBN2 TD AFW PMP 212 HS046 TRIP/THV 2FCV Functionality 0.57 0056BS 151 POS CNTL Pressure Switch to open U2 AOV 2FCV36386 WBN2 from AFW Supply 213 PS002 Functionality 0.83 Tank upon 0321 low pressure in U1 Condensate supply piping.

Solenoid valve to WBN1,2 open AFW Supply 214 FSV003 Tank insolation Functionality 0.83 6386 Valve 1,2FCV3 6386 WBN1 Safety Injection 215 FT63 Anchorage > 0.5 Pump Flow 151 WBN2 Safety Injection 216 Anchorage > 0.5 FT6320 Pump Flow Page B18

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode MAIN STEAM WBN1 LOOP 4 217 PI001 PRESSURE Anchorage 0.56 0027D (typical for each SG)

WBN1 TD AFW PMP 218 HS046 TRIP/THV 1FCV Functionality 0.57 0056BS 151 POS CNTL WBN0 HCLPF associated Fuel Oil Transfer SW360 with Item #404 219 Pmp Disconnect Anchorage 0.66 103C, Fuel Oil Storage SW 203C Tank. Rule of box.

220 Not Used WBN0 HCLPF associated PMP Fuel Oil System with Item #404 221 Anchorage 0.66 360103, Transfer Pump Fuel Oil Storage 203 Tank. Rule of box.

Level Indicating Transmitter for WBN0 the AFW Supply 222 LIT003 Anchorage 0.51 Tank and 227 High/Low Level Alarms HCLPF associated WBN0 Primary Cntrl with Item #267, 223 FU1360 Fuse for Fuel Oil and conservatively Anchorage 0.5 0103A Pump A Starter assigned as 0.5g.

Rule of box.

HCLPF associated WBN0 Secondary Cntrl with Item #267, 224 FU1360 Fuse for Fuel Oil and conservatively Anchorage 0.5 0103B Pump A Starter assigned as 0.5g.

Rule of box.

HCLPF associated WBN0 Primary Cntrl with Item #267, 225 FU1360 Fuse for Fuel Oil and conservatively Anchorage 0.5 0103C Pump A Starter assigned as 0.5g.

Rule of box.

WBN0 480 V FLEX Main FUDS 226 Panel A Main Functionality 0.57 360 Disconnect FP/AM Page B19

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN0 480 v FLEX Main FUDS 227 Panel B Main Functionality 0.57 360 Disconnect FP/BM WBN0 480v AC Vital 228 XSW236 Functionality 0.50 Transfer Switch IV 0004S WBN0 480v AC Vital 229 XSW236 Functionality 0.50 Transfer Switch III 0003S WBN0 480v AC Vital 230 XSW236 Functionality 0.50 Transfer Switch II 0002S WBN0 480v AC Vital 231 XSW236 Functionality 0.50 Transfer Switch I 0001S WBN0 480 V FLEX DG HCLPF assigned GNGC Neutral based on Junction 232 Functionality 0.57 360 Grounding Box subgroup DG/A, B Resistor Box from HCLPF calc WBN0 480 V FLEX DG 233 BKR360 Functionality 0.57 Circuit Breaker DG/A, B WBN1 Hydrogen Igniters screened 234 HTR268 Group A 34 0.5 (rugged) various igniters WBN2 Hydrogen Igniters screened 235 HTR268 Group B 34 0.5 (rugged) various igniters WBN0 Conservation vent screened 236 RFV003 valve for the AFW 0.5 (Table 2.4) 0005 Supply Tank.

WBN1 TD Aux Feedwater 237 FCV001 Pmp Governor screened 0.5 0052 Valve WBN2 TD Aux Feedwater 238 FCV001 Pmp Governor screened 0.5 0052 Valve Pressure indicator WBN0 screened 239 for the AFW 0.5 PI0031 (rugged)

Supply Tank Page B20

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode Pressure Switch to open U1 AOV 1FCV36386 WBN1 from AFW Supply screened 240 PS002 0.5 Tank upon low (rugged) 0320 pressure in U1 Condensate supply piping.

WBN0 3MW Diesel BD360 241 Generator 6.9KV Functionality 0.68 0003A, Switchgear 3B WBN2 Hydrogen 242 DXF268 Mitigation Anchorage 0.51 0002B Transformer WBN1 Hydrogen 243 DXF268 Mitigation Anchorage 0.51 0001A Transformer WBN0 DXF360 480 V FLEX DG 2 244 Functionality 0.57 DG/AP, KVA Sealed XFMR BP WBN0 6900V 3MW FLEX XFMR Diesel GEN 20 245 360 Functionality 0.58 KVA Dry Type 3A/1, Transformer 3B/1 WBN0 6900V 3MW FLEX XFMR Diesel GEN 5 KVA 246 360 Functionality 0.57 Dry Type 3A/2, Transformer 3B/2 WBN1 TDAFWP Control 247 PNL276 Anchorage 0.56 Panel L381 WBN2 TDAFWP Control 248 PNL276 Anchorage 0.56 Panel L381 WBN0 Fuel Oil Transfer 249 PNL360 Pump Control Functionality 0.65 DG/A1 Panel Page B21

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode 125V Vital Batt WBN0 CHGR I 480 V 250 XSW236 Functionality 0.58 FLEX Transfer 0001AS Switch 125V Vital Batt WBN0 CHGR 2 480 V 251 XSW236 Functionality 0.58 FLEX Transfer 0002AS Switch 125V Vital Batt WBN0 CHGR 3 480 V 252 XSW236 Functionality 0.58 FLEX Transfer 0003AS Switch 125V Vital Batt WBN0 CHGR 4 480 V 253 XSW236 Functionality 0.58 FLEX Transfer 0004AS Switch WBN0 480 V FLEX Fuse 254 PNL360 Functionality 0.57 Panel A FP/A WBN0 480 V FLEX Fuse 255 PNL360 Functionality 0.57 Panel B FP/B WBN1 AUX FW TURBINE 256 PNL276 SPEED CONTROL Functionality 0.85 L326S PANEL WBN2 AUX FW TURBINE 257 PNL276 SPEED CONTROL Functionality 0.85 L326S PANEL 3MW Diesel WBN0 Generator 258 RES360 Neutral Functionality 0.79 003A, 3B Grounding Resistor WBN1 AUX FEEDWATER 259 PNL276 Functionality 0.57 CONTROL L381A WBN2 AUX FEEDWATER 260 PNL276 Functionality 0.57 CONTROL L381A Page B22

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode FLEX COMMON WBN0 SPARE HP PUMP 261 XSW360 Functionality 0.57 TRANSFER HPCS SWITCH WBN1 DG 1AA Transfer 262 XSW82 Switch TO 6.9KV Functionality 0.57 A SD BD 1AA WBN2 DG 2AA Transfer 263 XSW82 Switch TO 6.9KV Functionality 0.57 A SD BD 2AA WBN1 DG 1BB Transfer 264 XSW82 Switch DG to SD Functionality 0.57 B BD 1BB WBN2 DG 2BB Transfer 265 XSW82 Switch DG to SD Functionality 0.57 B BD 2BB WBN0 FUDS 480 V FLEX DG 266 360 Pump Disconnect Functionality 0.57 DG/AP2, Switch BP2 WBN0 STR360 3MW FLEX Diesel 267 Anchorage 0.54 0103, GEN PMP Starter 203 WBN0 6900V 3MW FLEX SW360 268 Diesel GEN Fused Anchorage 0.5 0003A/1, Disconnect Switch 3B/1 WBN1 Reactor Level Cap 269 TE068 Anchorage > 0.5 tube Temp Comp 0380E HCLPF assigned based on WBN2 Reactor Vessel Instruments 270 PNL276 instrumentation Anchorage 0.52 mounted on L340 System II Panel unitstrut subgroup from HCLPF calc Page B23

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode HCLPF assigned based on WBN1 Reactor Vessel Instruments 271 PNL276 instrumentation Anchorage 0.52 mounted on L388 System I Panel unitstrut subgroup from HCLPF calc WBN2 Reactor Level Cap 272 TE068 Anchorage > 0.5 tube Temp Comp 0380E WBN0 AFW Supply Tank > 0.5 273 Anchorage LI3227 Level Indicator WBN1 > 0.5 274 RWST Level Anchorage LI6351 WBN2 > 0.5 275 RWST Level Anchorage LI6351 WBN1 > 0.5 TDAFW Pump 276 LPF3 Anchorage Flow 142 WBN2 > 0.5 TDAFW Pump 277 LPF3 Anchorage Flow 142 WBN1 > 0.5 278 LPF3 AFW Flow S/G 3 Anchorage 147B WBN2 > 0.5 279 LPF3 AFW Flow S/G 3 Anchorage 147B WBN1 > 0.5 280 LPF3 AFW Flow S/G 2 Anchorage 155A WBN2 > 0.5 281 LPF3 AFW Flow S/G 2 Anchorage 155A WBN1 > 0.5 282 LPF3 AFW Flow S/G 1 Anchorage 163B WBN2 > 0.5 283 LPF3 AFW Flow S/G 1 Anchorage 163B WBN1 > 0.5 284 LPF3 AFW Flow S/G 4 Anchorage 170A Page B24

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 > 0.5 285 LPF3 AFW Flow S/G 4 Anchorage 170A WBN1 S/G WR Level > 0.5 286 Anchorage LPL3111 Loop 4 WBN2 S/G WR Level > 0.5 287 Anchorage LPL3111 Loop 4 WBN1 S/G NR Level Loop > 0.5 288 Anchorage LPL3148 3 WBN2 S/G NR Level Loop > 0.5 289 Anchorage LPL3148 3 WBN1 S/G NR Level Loop > 0.5 290 Anchorage LPL3156 2 WBN2 S/G NR Level Loop > 0.5 291 Anchorage LPL3156 2 WBN1 S/G NR Level Loop > 0.5 292 Anchorage LPL3164 1 WBN2 S/G NR Level Loop > 0.5 293 Anchorage LPL3164 1 WBN1 S/G NR Level Loop > 0.5 294 Anchorage LPL3171 4 WBN2 S/G NR Level Loop > 0.5 295 Anchorage LPL3171 4 WBN1 S/G WR Level > 0.5 296 Anchorage LPL343 Loop 1 WBN2 S/G WR Level > 0.5 297 Anchorage LPL343 Loop 1 WBN1 S/G WR Level > 0.5 298 Anchorage LPL356 Loop 1 WBN2 S/G WR Level > 0.5 299 Anchorage LPL356 Loop 2 WBN1 S/G WR Level > 0.5 300 Anchorage LPL398 Loop 3 WBN2 S/G WR Level > 0.5 301 Anchorage LPL398 Loop 3 WBN1 > 0.5 302 LPL68 PZR Level Anchorage 335 WBN2 > 0.5 303 LPL68 PZR Level Anchorage 335 Page B25

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN0 > 0.5 304 SFP Level Anchorage LPL7842 WBN1 > 0.5 305 LPN92 Nuclear Flux Anchorage 131 WBN2 > 0.5 306 LPN92 Nuclear Flux Anchorage 132 WBN1 > 0.5 S/G Pressure Loop 307 LPP1 Anchorage 3

20A WBN2 > 0.5 S/G Pressure Loop 308 LPP1 Anchorage 3

20A WBN1 > 0.5 S/G Pressure Loop 309 LPP1 Anchorage 4

27B WBN2 > 0.5 S/G Pressure Loop 310 LPP1 Anchorage 4

27B WBN1 S/G Pressure Loop > 0.5 311 Anchorage LPP12A 1 WBN2 S/G Pressure Loop > 0.5 312 Anchorage LPP12A 1 WBN1 S/G Pressure Loop > 0.5 313 Anchorage LPP19A 2 WBN2 S/G Pressure Loop > 0.5 314 Anchorage LPP19A 2 WBN1 > 0.5 315 LPP68 RCS WR Pressure Anchorage 68 WBN2 > 0.5 316 LPP68 RCS WR Pressure Anchorage 66 WBN1 > 0.5 Containment 317 LPPD30 Anchorage Pressure 310 WBN2 > 0.5 Containment 318 LPPD30 Anchorage Pressure 310 Page B26

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 > 0.5 Containment 319 LPT30 Anchorage Temperature 1032 WBN2 > 0.5 Containment 320 LPT30 Anchorage Temperature 1032 WBN1 RCS WR Thot Loop > 0.5 321 Anchorage LPT681 1 WBN2 RCS WR Thot Loop > 0.5 322 Anchorage LPT681 1 WBN1 > 0.5 RCS WR Tcold Loop 323 LPT68 Anchorage 1

18 WBN2 > 0.5 RCS WR Tcold Loop 324 LPT68 Anchorage 1

18 WBN1 > 0.5 RCS WR Tcold Loop 325 LPT68 Anchorage 2

41 WBN2 > 0.5 RCS WR Tcold Loop 326 LPT68 Anchorage 2

41 WBN1 > 0.5 RCS WR Tcold Loop 327 LPT68 Anchorage 3

60 WBN2 > 0.5 RCS WR Tcold Loop 328 LPT68 Anchorage 3

60 WBN1 > 0.5 RCS WR Tcold Loop 329 LPT68 Anchorage 4

83 WBN2 > 0.5 RCS WR Tcold Loop 330 LPT68 Anchorage 4

83 WBN1 PORV AND AFW 331 PNL276 LCV STM GEN 3 & Anchorage 0.52 L1000 4 PNL WBN2 PORV AND AFW 332 PNL276 LCV STM GEN 3 & Anchorage 0.52 L1000 4 PNL Page B27

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 PORV AND AFW 333 PNL276 LCV STM GEN 1 & Anchorage 0.52 L1001 2 PNL WBN2 PORV AND AFW 334 PNL276 LCV STM GEN 1 & Anchorage 0.52 L1001 2 PNL WBN1 Incore 335 PNL094 Thermocouple Anchorage 0.52 0008AJ Mon Sys Jbox WBN1 Incore 336 PNL094 Thermocouple Anchorage 0.52 0008BJ Mon Sys Jbox WBN0 DPL360 480Volt 337 Functionality 0.68 0003A/1, Distribution Panel 3B/1 WBN0 DPL360 120/240 VAC 338 Functionality 0.68 0003A/2, Panelboard 3B/2 WBN2 Hydrogen 339 DPL268 Mitigation Functionality 0.57 0002B Distribution Panel WBN1 Hydrogen 340 DPL268 Mitigation Functionality 0.57 0001A Distribution Panel WBN0 FUSD 480 V FLEX DG 341 360 Pump Fusible Functionality 0.57 DG/AP1, Disc Switch BP1 WBN0 480V FLEX/ESBO DG360 342 225 KVA Diesel Functionality 0.57 000A, Generator 000B WBN0 DG360 6900V 3MW 343 Anchorage 0.87 0003A, Diesel Generator 3B Page B28

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 PMP TD Aux Feedwater 344 Anchorage 0.59 003 Pump 1AS 0001AS WBN2 PMP TD Aux Feedwater 345 Anchorage 0.59 003 Pump 2AS 0002AS WBN0 PMP Fuel Oil Transfer 346 360 Functionality 0.57 Pump DG/A1, B1 WBN1 347 PMP HP FLEX Pump Functionality 0.5 360HP01 WBN2 348 PMP HP FLEX Pump Functionality 0.5 360HP01 WBN1 349 PMP FLEX IP PUMP 01 Functionality 0.5 360IP01 WBN2 350 PMP FLEX IP PUMP 01 Functionality 0.5 360IP01 WBN1 351 PMP FLEX IP PUMP 02 Functionality 0.5 360IP02 WBN2 352 PMP FLEX IP PUMP 02 Functionality 0.5 360IP02 FCV SHARED AFW WBN1 TANK OUTLET 353 FCV003 Functionality 0.83 PIPE TO U1 6386 CONDENSATE FCV FOR AFW WBN2 Supply Tank 354 FCV003 Functionality 0.83 Outlet Piping to 6386 U2 Condensate WBN0 SFP HEAT 355 FCV070 EXCHANGER B Functionality 0.69 0194B CCS SUPPLY Page B29

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN0 SFP HEAT 356 FCV070 EXCHANGER A Functionality 0.69 0197A CCS SUPPLY WBN0 Sta Ser & Cntl Air 357 FCV067 Cmpr Supply Hdr Functionality 0.83 0205 A Isol valve WBN0 Sta Ser & Cntl Air 358 FCV067 Cmpr Supply Hdr Functionality 0.83 0208 B Isol valve WBN1 TD Aux Feedwater 359 FCV001 Pmp Trip & Functionality 0.7 051 Throttle Valve WBN2 TD Aux Feedwater 360 FCV001 Pmp Trip & Functionality 0.7 051 Throttle Valve WBN2 ERCW Header B 361 FCV003 TD AFW PMP Functionality 1.14 0179AB SUCT (PS144)

WBN2 ERCW Header A 362 FCV003 TD AFW PMP Functionality 1.14 0136AA SUCT (PS139)

WBN2 ERCW Header A 363 FCV003 TD AFW PMP Functionality 1.14 0136BA SUCT WBN2 ERCW Header B 364 FCV003 TD AFW PMP Functionality 1.14 0179BB SUCT WBN1 ERCW Header A 365 FCV003 TD AFW PMP Functionality 1.14 0136AA SUCT (PS139)

WBN1 ERCW Header A 366 FCV003 TD AFW PMP Functionality 1.14 0136BA SUCT WBN1 ERCW Header B 367 FCV003 TD AFW PMP Functionality 1.14 0179AB SUCT (PS144)

WBN1 ERCW Header B 368 FCV003 TD AFW PMP Functionality 1.14 0179BB SUCT WBN1 CCS HX C SUP 369 FCV067 Functionality 0.92 FROM HDR 1A 0147A Page B30

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 CCS HX C SUP 370 FCV067 Functionality 0.92 FROM HDR 1B 0458A WBN1 N2 TANK NO. 1 371 TANK3 SUPPLY TO 1LCV Anchorage 0.63 0402A 0030173B WBN1 N2 TANK NO. 1 TANK 372 SUP TO 1PCV Anchorage 0.63 001 0010012B 0405A WBN2 N2 TANK NO. 1 TANK 373 SUP TO 2PCV Anchorage 0.63 001 0010012B 0405A WBN1 N2 TANK NO. 2 TANK 374 SUP TO 1PCV Anchorage 0.63 001 0010012B 0405B WBN2 N2 TANK NO. 2 TANK 375 SUP TO 2PCV Anchorage 0.63 001 0010012B 0405B WBN1 N2 TANK NO. 1 TANK 376 SUP TO 1PCV Anchorage 0.63 001 0010030B 0406A WBN2 N2 TANK NO. 1 TANK 377 SUP TO 2PCV Anchorage 0.63 001 0010030B 0406A WBN1 N2 TANK NO. 2 TANK 378 SUP TO 1PCV Anchorage 0.63 001 0010030B 0406B WBN2 N2 TANK NO. 2 TANK 379 SUP TO 2PCV Anchorage 0.63 001 0010030B 0406B WBN1 N2 TANK NO. 1 TANK 380 SUP TO 1PCV Anchorage 0.63 001 0010023A 0407A Page B31

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 N2 TANK NO. 1 TANK 381 SUP TO 2PCV1 Anchorage 0.63 001 0023A 0407A WBN1 N2 TANK NO. 2 TANK 382 SUP TO 1PCV Anchorage 0.63 001 0010023A 0407B WBN2 N2 TANK NO. 2 TANK 383 SUP TO 2PCV1 Anchorage 0.63 001 0023A 0407B WBN1 N2 TANK NO. 1 TANK 384 SUP TO 1PCV Anchorage 0.63 001 0010005A 0408A WBN2 N2 TANK NO. 1 TANK 385 SUP TO 2PCV Anchorage 0.63 001 0010005A 0408A WBN1 N2 TANK NO. 2 TANK 386 SUP TO 1PCV Anchorage 0.63 001 0010005A 0408B WBN2 N2 TANK NO. 1 TANK 387 SUP TO 2PCV Anchorage 0.63 001 0010005A 0408B WBN2 N2 TANK NO. 1 388 TANK3 SUPPLY TO 2LCV Anchorage 0.63 0402A 0030173B WBN1 N2 TANK NO. 2 389 TANK3 SUPPLY TO 1LCV Anchorage 0.63 0402B 0030173B WBN2 N2 TANK NO. 2 390 TANK3 SUPPLY TO 2LCV Anchorage 0.63 0402B 0030173B WBN1 N2 TANK NO. 1 391 TANK3 SUPPLY TO 1LCV Anchorage 0.63 0402C 0030174B Page B32

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 N2 TANK NO. 1 392 TANK3 SUPPLY TO 2LCV Anchorage 0.63 0402C 0030174B WBN1 N2 TANK NO. 2 393 TANK3 SUPPLY TO 1LCV Anchorage 0.63 0402D 0030174B WBN2 N2 TANK NO. 2 394 TANK3 SUPPLY TO 2LCV Anchorage 0.63 0402D 0030174B WBN1 N2 TANK NO. 1 395 TANK3 SUP TO 1LCV Anchorage 0.63 0403A 0030172A WBN2 N2 TANK NO. 1 396 TANK3 SUP TO 2LCV3 Anchorage 0.63 0403A 172A WBN1 N2 TANK NO. 2 397 TANK3 SUP TO 1LCV Anchorage 0.63 0403B 003172A WBN2 N2 TANK NO. 2 398 TANK3 SUP TO 2LCV3 Anchorage 0.63 0403B 172A WBN1 N2 TANK NO. 1 399 TANK3 SUP TO 1LCV Anchorage 0.63 0403C 0030175A WBN2 N2 TANK NO. 1 400 TANK3 SUP TO 2LCV3 Anchorage 0.63 0403C 175A WBN1 N2 TANK NO. 2 401 TANK3 SUP TO 1LCV Anchorage 0.63 0403D 0030175A WBN2 N2 TANK NO. 2 402 TANK3 SUP TO 2LCV3 Anchorage 0.63 0403D 175A WBN0 AFW Supply Tank 403 TANK Anchorage 0.51 500,000 gallons 0030226 WBN0 6900V 3MW FLEX TANK 404 DG Fuel Oil Anchorage 0.66 360113, Storage Tank 213 Page B33

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 TD Aux FW PMP 405 CLR003 Functionality 3 Oil Cooler 0001B WBN2 TD Aux FW PMP 406 CLR003 Functionality 3 Oil Cooler 0001B WBN2 Transfer Sw in 407 RLY046 Chatter 1.55 Aux Pos Isol Rly 0057S WBN2 B21 Relay AFPT 408 RLY046 Trip & Throttle Chatter 1.3 B002/1S Vlv Photo Iso WBN2 B22 Relay AFPT 409 RLY046 Trip & Throttle Chatter 1.3 B002/2S Vlv Photo Iso WBN2 B23 Relay AFPT 410 RLY046 Speed Control Chatter 1.55 B002/3S Instr Pwr BA & BB Relay WBN2 AFPT Speed 411 RLY046 Chatter 1.79 Control Buffer BAS Relay WBN2 BA1 Relay AFPT 412 RLY046 Speed Control Chatter 1.79 BA1S Buffer BA & BB Relay WBN2 AFPT Speed 413 RLY046 Chatter 1.79 Control Buffer BBS Relay WBN2 Aux FW Pump Vlv 414 RLY046 Chatter 1.4 Sep Relay R/AA WBN2 Aux FW Pump Vlv 415 RLY046 Chatter 1.4 Sep Relay R/BB WBN2 AFPT ACC Reset 416 RLY046 Chatter 1.79 Relay R1S WBN2 AFPT ACC Reset 417 RLY046 Chatter 1.79 Relay R2S Page B34

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN2 AFPT SUP Xfer 418 RLY046 FCV115,16 & Chatter 1.79 R4A 51 Sep Relay TR A Aux Feed Pump WBN2 Trb Stm Supply 419 RLY046 Chatter 1.62 Xfer Sep Relay TR R5A A

WBN2 Turb/Mtr Driven 420 RLY046 Aux FW Pump Chatter 1.4 RA1A Vlvs Aux Relay WBN2 Turb/Mtr Driven 421 RLY046 Aux FW Pump Vlv Chatter 1.4 RA2A SSEP Relay AFPT Pump 2 WBN2 FCV151 Mtr Dr 422 RLY046 Chatter 1.4 Vlv 2LCV3156 &

RASS 164 WBN2 Turb/Mtr Driven 423 RLY046 Aux FW Pump Chatter 1.4 RB1B Vlvs Aux Relay WBN2 Turb Driven Aux 424 RLY046 FW Pump Vlv SEP Chatter 1.4 RB2B Relay AFPT Pump 2 WBN2 FCV151 Mtr Dr 425 RLY046 Chatter 1.4 Vlv 2LCV3171 &

RBSS 148 WBN2 AFPT SUP Xfer 426 RLY046 FCV115,16 & Chatter 1.79 SSTS 51 Sep Relay WBN1 Transfer Sw in 427 RLY046 Chatter 1.55 Aux Pos Isol Rly 0057S WBN1 B21 Relay AFPT 428 RLY046 Trip & Throttle Chatter 1.3 B002/1S Vlv Photo Iso WBN1 B22 Relay AFPT 429 RLY046 Trip & Throttle Chatter 1.3 B002/2S Vlv Photo Iso WBN1 B23 Relay AFPT 430 RLY046 Speed Control Chatter 1.55 B002/3S Instr Pwr Page B35

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode BA & BB Relay WBN1 AFPT Speed 431 RLY046 Chatter 1.79 Control Buffer BAS Relay WBN1 BA1 Relay AFPT 432 RLY046 Speed Control Chatter 1.79 BA1S Buffer BA & BB Relay WBN1 AFPT Speed 433 RLY046 Chatter 1.79 Control Buffer BBS Relay WBN1 Aux FW Pump Vlv 434 RLY046 Chatter 1.4 Sep Relay R/AA WBN1 Aux FW Pump Vlv 435 RLY046 Chatter 1.4 Sep Relay R/BB WBN1 AFPT ACC Reset 436 RLY046 Chatter 1.79 Relay R1S WBN1 AFPT ACC Reset 437 RLY046 Chatter 1.79 Relay R2S WBN1 AFPT SUP Xfer 438 RLY046 FCV115,16 & Chatter 1.79 R4A 51 Sep Relay TR A Aux Feed Pump WBN1 Trb Stm Supply 439 RLY046 Chatter 1.62 Xfer Sep Relay TR R5A A

WBN1 Turb/Mtr Driven 440 RLY046 Aux FW Pump Chatter 1.4 RA1A Vlvs Aux Relay WBN1 Turb/Mtr Driven 441 RLY046 Aux FW Pump Vlv Chatter 1.4 RA2A SSEP Relay AFPT Pump 2 WBN1 FCV151 Mtr Dr 442 RLY046 Chatter 1.4 Vlv 2LCV3156 &

RASS 164 Page B36

Watts Bar Nuclear Plant ESEP Report Item Failure UNID Description Notes/Comments HCLPF (g)

1. Mode WBN1 Turb/Mtr Driven 443 RLY046 Aux FW Pump Chatter 1.4 RB1B Vlvs Aux Relay WBN1 Turb Driven Aux 444 RLY046 FW Pump Vlv SEP Chatter 1.4 RB2B Relay AFPT Pump 2 WBN1 FCV151 Mtr Dr 445 RLY046 Chatter 1.4 Vlv 2LCV3171 &

RBSS 148 WBN1 AFPT SUP Xfer 446 RLY046 FCV115,16 & Chatter 1.79 SSTS 51 Sep Relay WBN1 TDAFW 447 STR046 Trip/Throttle Functionality 0.57 0056AS Motor Starter WBN2 TDAFW 448 STR046 Trip/Throttle Functionality 0.57 0056AS Motor Starter WBN1 Reactor Vessel Screened > 0.5 449 FSV68 Head Vent 394 Isolation Valve 450 WBN1 Reactor Vessel Screened > 0.5 FSV68 Head Vent 397 Throttle Valve 451 WBN2 Reactor Vessel Screened > 0.5 FSV68 Head Vent 395 Isolation Valve 452 WBN2 Reactor Vessel Screened > 0.5 FSV68 Head Vent 396 Throttle Valve Page B37