Text

Compliance Status Letter and Final Integrated Plan in Response to the March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049)
	ML14303A546
Person / Time
Site:	Watts Bar
Issue date:	10/30/2014
From:	James Shea; Tennessee Valley Authority
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	CNL-14-191, EA-12-049
	Download: ML14303A546 (112)
	v • d • e

Enclosure 2, Attachment 3 is to be withheld from public disclosure under 10 CFR 2.390(d)(1).

When separated from this submittal, this letter is decontrolled.

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-14-191 October 29, 2014 10 CFR 2.202 10 CFR 50.4 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:

Compliance Status Letter and Final Integrated Plan in Response to the March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) for Watts Bar Nuclear Plant (TAC Nos. MF0950 and MF1177)

References:

1. Letter from NRC to TVA, Issuance of Order to Modify Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order EA-12-049), dated March 12, 2012 (ML12054A736)

2. NRC Interim Staff Guidance JLD-ISG-2012-01, Compliance with Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, Revision 0, dated August 29, 2012 (ML12229A174)

3. NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide, Revision 0, August 2012 (ML12242A378)

4. Letter from TVA to NRC, Tennessee Valley Authority - Initial Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements Mitigation Strategies for Beyond-Design-Basis External Events (Order EA-12-049), dated October 29, 2012 (ML12307A104)

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U.S. Nuclear Regulatory Commission CNL-14-191 Page 2 October 29, 2014

5. Letter from TVA to NRC, Tennessee Valley Authority (TVA) - Overall Integrated Plan in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) for Watts Bar Nuclear Plant, dated February 28, 2013 (ML13067A030).

6. Letter from TVA to NRC, First Six-Month Status Report in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) for Watts Bar Nuclear Plant, dated August 28, 2013 (ML13247A288).

7. Letter from NRC to TVA, Watts Bar Nuclear Plant, Units 1 and 2 - Interim Staff Evaluation Relating to Overall Intergraded Plan in Response to Order EA-12-049 (Mitigation Strategies) (TAC Nos. MF0950 and MF1177), dated December 20, 2013 (ML13343A025).

8. Letter from TVA to NRC, Revised Overall Integrated Plan in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) for Watts Bar Nuclear Plant (TAC Nos.

MF0950 and MF1177), dated February 7, 2014 (ML14062A050).

9. Letter from TVA to NRC, Response to NRC Staff Audit Question Clarification for Watts Bar Nuclear Plant, Units 1 and 2 Mitigation Strategies Integrated Plan, Phase 2 Electrical Strategy (TAC Nos. MF0950 and MF1177), dated March 28, 2014.

10. Letter from TVA to NRC, Third Six-Month Status Report in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) for Watts Bar Nuclear Plant (TAC Nos.

MF0950 and MF1177), dated August 28, 2014 (ML14248A517).

11. Letter from NRC to TVA, Summary of September 24, 2014, Meeting with Tennessee Valley Authority Regarding the Watts Bar Nuclear Plant, Unit 2, Response to Order EA 12-049 on Mitigating Strategies, dated October 17, 2014 (ML14274A148)

On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued an order (Reference 1) to Tennessee Valley Authority (TVA). Reference 1 was immediately effective and directed TVA to implement mitigation strategies for beyond-design-basis external events. Specific requirements are outlined in Attachment 2 of Reference 1.

Reference 1 required submission of an initial status report 60 days following issuance of the final interim staff guidance (Reference 2) and an overall integrated plan pursuant to Section IV, Condition C. Reference 2 endorses industry guidance document Nuclear Energy Institute (NEI) 12-06, Revision 0 (Reference 3) with clarifications and exceptions identified in Reference 2.

Reference 4 provided the TVA initial status report regarding mitigation strategies.

U.S. Nuclear Regulatory Commission CNL-14-191 Page 3 October 29, 2014 On February 28, 2013, TVA submitted an Overall Integrated Plan (OIP) in response to the March 12, 2012 Commission Order modifying licenses with regards to requirements for mitigation strategies for beyond-design-basis external events, Order number EA-12-049, for the Watts Bar Nuclear Plant (WBN), Units 1 and 2 (Reference 5). On August 28, 2013, TVA provided the first six-month status report to the OIP (Reference 6).

The OIP submitted in Reference 5 employed a strategy using reactor coolant pump (RCP) low leakage seals. TVA revised its strategy to use the existing conventional RCP seals. This change in RCP seals required a revision to the OIP. These changes were presented and discussed with the NRC through the mitigation strategies audit process. Based on a review of TVAs plan, including the six-month update, and information obtained through the mitigation strategies audit process, the NRC concluded in its Interim Staff Evaluation that the plan, when properly implemented, will meet the requirements of Order EA-12-049 at WBN, Units 1 and 2 (Reference 7).

The Interim Staff Evaluation included two open items. Open item 3.2.1.6.A required revision to the Sequence of Events due to use of the conventional RCP seals, for reanalysis by the NRC.

On February 7, 2014, TVA provided the revised OIP (Reference 8) which included the required revision to the Sequence of Events. Reference 8 also served as the second six-month status report.

The second open item, 3.2.4.8.A, required resolution for justification regarding use of pre-staged diesel generators. TVA provided the justification regarding use of pre-staged diesel generators on March 28, 2014 (Reference 9). On August 28, 2014, TVA provided the third six-month status report to the OIP (Reference 10).

Section IV, Condition C.3, of Reference 1 requires licensees to report to the Commission when full compliance with the requirements described in Attachment 2, Requirements for Mitigation Strategies for Beyond-Design-Basis Events at Operating Reactor Sites and Construction Permit Holders, of Reference 1 is achieved. On September 24, 2014, a teleconference was held between TVA and the NRC (Reference 11). In the discussion, TVA communicated its intention to submit a compliance letter for Order EA-12-049 with open items.

The purpose of this letter is to provide a status of compliance to the JLD regarding Section IV, Condition C.3, of Reference 1, for WBN, Units 1 and 2. Specifically, Enclosure 1 to the letter provides the status of compliance to the requirements described in Attachment 2 of Reference 1. Enclosure 2 provides the WBN, Units 1 and 2 FLEX Final Integrated Plan.

The information provided in Enclosure 2, Attachment 3 is considered to contain information concerning physical protection not otherwise designated as Safeguards Information and is designated Security Sensitive Information as defined in 10 CFR 2.390(d)(1). Accordingly, TVA requests that the information provided in Enclosure 2, Attachment 3 to this letter be withheld from public disclosure. provides a list of commitments as described in Enclosures 1 and 2. If you have any questions regarding this report, please contact Gordon Arent at (423) 365-2004.

U.S. Nuclear Regulatory Commission CNL-14-191 Page 4 October 29, 2014 I declare under penalty of perjury that the foregoing is true and correct. Executed on the 29th day of October 2014.

Respectfully, J. W. Shea Vice President, Nuclear Licensing

Enclosures:

1. Tennessee Valley Authority Watts Bar Nuclear Plant Units 1 and 2, Mitigation Strategies (FLEX) Compliance Status in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order EA-12-049)

2. Tennessee Valley Authority Watts Bar Nuclear Plant Units 1 and 2, FLEX Final Integrated Plan

3. List of Commitments cc (Enclosures):

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 NRC Senior Resident Inspector - Watts Bar Nuclear Plant NRR JLD Project Manager - Watts Bar Nuclear Plant J. W. Shea Digitally signed by J. W. Shea DN: cn=J. W. Shea, o=Tennessee Valley Authority, ou=Nuclear Licensing, email=jwshea@tva.gov, c=US Date: 2014.10.29 22:13:20 -04'00'

ENCLOSURE 1 TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT UNITS 1 AND 2, MITIGATION STRATEGIES (FLEX) COMPLIANCE STATUS IN RESPONSE TO THE MARCH 12, 2012, COMMISSION ORDER MODIFYING LICENSES WITH REGARD TO REQUIREMENTS FOR MITIGATION STRATEGIES FOR BEYOND-DESIGN-BASIS EXTERNAL EVENTS (ORDER EA-12-049)

Introduction Watts Bar Nuclear Plant (WBN) developed an Overall Integrated Plan (OIP)

(Reference 1) for documenting the diverse and flexible strategies (FLEX), in response to Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, (Reference 2). A Final Integrated Plan has been developed and is provided in Enclosure 2 of this letter. The information provided herein documents compliance status for WBN, Units 1 and 2 pursuant to Section IV, Condition C.3, of Reference 1 as of October 24, 2014.

Watts Bar Nuclear Plant has provided responses for Units 1 and 2 to the following Interim Staff Evaluation (ISE) Open and Confirmatory (Reference 7), Licensee Identified Open Items and Audit Questions/Audit Report Open Items per the following:

x ISE Open Items - TVA is finalizing responses to the ISE Open Items. Open item 3.2.1.6.A was submitted in Reference 8. Open item 3.2.4.8.A was submitted in Reference 9.

x ISE Confirmatory Items - TVA is finalizing responses to the ISE Confirmatory Items.

x Licensee Identified Open Items - Complete pending NRC closure. Open items are statused in the Final Integrated Plan provided in Enclosure 2 of this letter.

x Audit Questions/Audit Report Open Items - TVA is finalizing responses to the Audit Questions/Audit Report Open Items.

TVA will provide under separate cover a Table describing a summary answer for each of the items above that describes the documents which provided the technical basis for the answer by December 1, 2014.

Compliance with specific elements of the mitigation strategies order is documented in of this Enclosure. TVA will provide a letter stating WBN is in full compliance with Order EA-12-049 and the open items described below are closed by December 17, 2014.

Milestone Schedule - Items Complete The Milestone Schedule - Items Complete is provided in Enclosure 2, Tennessee Valley Authority Watts Bar Nuclear Plant Units 1 and 2, FLEX Final Integrated Plan, Attachment 2.

Page E1-1 of 6 CNL-14-191

ENCLOSURE 1 ATTACHMENT 1 Order EA-12-049 Compliance Elements Summary The elements identified below for Watts Bar Nuclear Plant (WBN) Units 1 and 2, as well as the Overall Integrated Plan (Reference 1), the 6-Month Status Reports (References 6, 8, and 10), the response to NRC Staff Audit Question providing an alternate justification (Reference 9), and the Final Integrated Plan provided in Enclosure 2 of this letter demonstrate compliance with Order EA-12-049, with open items.

Strategies - In work Watts Bar Nuclear Plant Units 1 and 2 strategies are in compliance with Order EA-12-049. TVA is finalizing responses to strategy related Open Items, Confirmatory Items, or Audit Questions/Audit Report Open Items.

Modifications - In work The modifications required to support the FLEX strategies for WBN Units 1 and 2 are in final implementation in accordance with the station design control process. See Table 1 for a description of the remaining work for modifications as implemented by the referenced FLEX Design Change Notices (DCNs) and Engineering Design Change Requests (EDCRs). TVA will provide a status of completion of these DCNs and EDCRs by December 17, 2014.

Equipment - Procured and Maintenance & Testing - In work The equipment required to implement the FLEX strategies for WBN, Units 1 and 2 has been procured in accordance with NEI 12-06, Section 11.1 and 11.2. All equipment has been received at WBN except for the second of two trucks used for equipment deployment and snow removal.

Equipment has been initially tested/performance verified as identified in NEI 12-06, Section 11.5, and is available for use. Equipment has had satisfactory Factory Acceptance Tests (FATs) witnessed by TVA employees.

Maintenance and testing will be conducted through the use of the WBN Preventative Maintenance (PM) program such that equipment reliability is achieved. FLEX PM instructions have been drafted and will be issued in accordance with the site PM control process. No FLEX PMs have been performed to date. Site PMs will be scheduled for implementation in the appropriate Functional Equipment Group (FEG) weeks based on their frequency as scheduled in the WBN PM program.

TVA will provide the status of equipment and completion of the PMs by December 17, 2014.

Page E1-2 of 6 CNL-14-191

Protected Storage - In work The WBN storage facility, the FLEX Equipment Storage Building (FESB), required to implement the FLEX strategies for WBN, Units 1 and 2 is field work complete with final DCN package closure remaining. The FESB provides protection from applicable site hazards.

Procedures - In work FLEX Support Instructions (FSIs) for WBN, Units 1 and 2 have been developed and integrated with existing procedures. The FSIs and affected existing procedures are being validated under the site procedure control process as DCNs and turn-over of Unit 2 systems are completed. The FSIs and affected existing procedures will be effective in accordance with the site procedure control program at start-up of Unit 2.

Training - In work Training for WBN, Units 1 and 2 has been completed in accordance with an accepted training process as recommended in NEI 12-06, Section 11.6 except for the following:

x Training associated with interaction among the Emergency Response Organization, the National SAFER Response Centers and offsite FLEX staging areas has not been conducted. TVA will provide a status of completion of training by December 17, 2014.

Staffing - Complete The staffing study for WBN has been completed in accordance with 10 CFR 50.54(f),

"Request for Information Pursuant to Title 10 of the Code of Federal Recommendations 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," Recommendation 9.3, dated March 12, 2012 (Reference 5), as documented in TVAs letter to NRC, Tennessee Valley Authority (TVA) - Response to March 12, 2012, Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident,, Recommendation 9.3, Emergency Preparedness - Staffing, Requested Information Items 1, 2, and 6 - Phase 2 Staffing Assessment, (Reference 10).

National SAFER Response Centers - Complete TVA contracted with Pooled Equipment Inventory Company (PEICo) and has joined the Strategic Alliance for FLEX Emergency Response (SAFER) Team Equipment Committee for off-site facility coordination. It has been confirmed that PEICo is ready to support WBN with Phase 3 equipment stored in the National SAFER Response Centers in accordance with the site specific SAFER Response Plan. The site specific plan for WBN, SAFER Response Plan for Watts Bar Nuclear Plant, Revision 3, was issued September 25, 2014 (Reference 9).

Page E1-3 of 6 CNL-14-191

Validation - In work WBN is completing validation in accordance with industry guidance to assure required tasks, manual actions and decisions for FLEX strategies are feasible and may be executed within the constraints identified in the Final Integrated Plan (FIP) for Order EA-12-049. Validation is expected to be completed as procedures are completed and transfer of Unit 2 systems from construction to operations is completed. TVA will provide a status of completion of validation by December 17, 2014.

FLEX Program Document - In work The TVA WBN FLEX Program Document has been developed in accordance with the requirements of NEI 12-06. The document is in final review in accordance with the TVA procedure control process. TVA will provide a status of completion of the program document by December 17, 2014.

References The following references support the WBN, Units 1 and 2 FLEX Compliance Document:

1. Letter from TVA to NRC, Tennessee Valley Authority (TVA) - Overall Integrated Plan in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) for Watts Bar Nuclear Plant, dated February 28, 2013 (ML13067A030).

2. NRC Order Number EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, dated March 12, 2012 (ML12229A174).

3. Letter from TVA to NRC, First Six-Month Status Report in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) for Watts Bar Nuclear Plant, dated August 28, 2013 (ML13247A288).

4. Letter from TVA to NRC, Revised Overall Integrated Plan in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) for Watts Bar Nuclear Plant (TAC Nos. MF0950 and MF1177), dated February 7, 2014 (ML14062A050).

5. NRC Letter, "Request for Information Pursuant to Title 10 of the Code of Federal Recommendations 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).

6. Letter from TVA to NRC, Response to NRC Staff Audit Question Clarification for Watts Bar Nuclear Plant, Units 1 and 2 Mitigation Strategies Integrated Plan, Phase 2 Electrical Strategy (TAC Nos. MF0950 and MF1177), dated March 28, 2014.

Page E1-4 of 6 CNL-14-191

7. Letter from NRC to TVA, Watts Bar Nuclear Plant, Units 1 and 2 - Report for the Audit Regarding Implementation of Mitigations Strategies and Reliable Spent Fuel Instrumentation Related to Orders EA-12-049 and EA-12-051 (TAC Nos. MF0950, MF1177, MF0951 and MF1178), dated May 15, 2014 (ML14128129)

8. Letter from TVA to NRC, Third Six-Month Status Report in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049) for Watts Bar Nuclear Plant (TAC Nos. MF0950 and MF1177), dated August 28, 2014 (ML14248A517).

9. SAFER Response Plan for Watts Bar Nuclear Plant, Revision 3, issued September 25, 2014

10. Letter from TVA to NRC, Tennessee Valley Authority (TVA) - Response to March 12, 2012, Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, Enclosure 5, Recommendation 9.3, Emergency Preparedness - Staffing, Requested Information Items 1, 2, and 6 - Phase 2 Staffing Assessment, dated October 6, 2014.

Page E1-5 of 6 CNL-14-191

ENCLOSURE 1 TABLE 1 REMAINING WORK STATUS OF ENGINEERING DESIGN NOTICES AND ENGINEERING DESIGN CHANGE REQUESTS (EDCRs)

DCN # /

EDCR #

DESCRIPTION REMAINING WORK DCN 59397 Tritiated Water Storage Tank Design and Construction DCN is field work complete - DCN is paper closure status.

DCN 59675 Install Two 225 KVA Air Cooled Diesel Generators on the Auxiliary Building Roof to Mitigate Loss of All AC Beyond-Design-Basis Event DCN is field work complete, testing/commissioning of the diesel generators (DGs) is in progress. Both DGs have been load tested and currently undergoing break in runs.

DCN 59084 FLEX Equipment Storage Building DCN is field work complete - DCN is paper closure status.

DCN 60060 Add AFW Supply Tank with Connection Piping and Valves DCN is field work complete - DCN is paper closure status.

DCN 60384 EP Communications - Harris Radio Final Post Modification Testing (PMT).

DCN 60853 Install Two 3 MWE Air Cooled DGs in FESB and Connect to EDGS DCN is field work complete, final fuel oil flushes are starting. In parallel, testing/commissioning of the DGs is in progress. Both DGs have been started satisfactorily and TVA plans to perform the load test.

DCN 61784 DCN Corresponds to the 0-TI-2 Case 6 and Case 5 from EDCRs EDCR-2 60751 and EDCR-2 60993 DCN closure will follow EDCR 60751 listed below.

DCN 62889 Locate and Install Various System 360 Equipment and Components All storage boxes are installed per DCN. Road work and pads for portable equipment is near completion.

DCN 63030 Install HP/IP Pumps in Auxiliary Building to Support FLEX Strategies All pumps are in the Auxiliary Building. Conduit and cable is installed. Final installation, terminations, phase rotation checks, and testing remains.

EDCR 60749 Install Nitrogen Backup Control Stations for the SG PORVs and the TDAFWP LCVS to Allow Operators to Control the PORVs and LCVS at an Elevation Above the Probable Maximum Flood (PMF)

Field work is progressing and is scheduled to be complete by December 17, 2014.

EDCR 60751 Install New Piping, Valves and Hose Connection on Auxiliary Feedwater System Field work is progressing and is scheduled to be complete by December 17, 2014.

Page E1-6 of 6 CNL-14-191

ENCLOSURE 2 TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT UNITS 1 AND 2, FLEX FINAL INTEGRATED PLAN CNL-14-191

E2-2 of 84 General Integrated Plan Elements Watts Bar Units 1 and 2 Determine Applicable Extreme External Hazard Ref: NEI 12-06 Section 4.0 -9.0 JLD-ISG-2012-01 Section 1.0 The Watts Bar site has been evaluated and the following applicable hazards have been identified:

x Seismic events x

External flooding x

Severe storms with high winds x

Snow, ice, and extreme cold x

Extreme heat The Watts Bar site has been reviewed against the Nuclear Energy Institute (NEI) guidance document NEI 12-06 (Reference 2) and determined that the hazards Flexible and Diverse Coping Mitigation Strategies (FLEX) equipment should be protected from include seismic; external flooding; severe storms with high winds; snow, ice and extreme cold; and extreme high temperatures. Watts Bar has determined the functional threats from each of these hazards and identified FLEX equipment that may be affected. The FLEX storage locations provide the protection required from these hazards. Watts Bar has developed procedures and processes to address plant strategies for responding to these various hazards.

Seismic:

Per NEI 12-06 (Reference 2), seismic hazards must be considered for all nuclear sites. As a result, the credited FLEX equipment has been assessed based on the current WBN seismic licensing basis, with margin added as indicated below, to ensure that the equipment remains accessible and functional after a Beyond Design Basis External Event (BDBEE) and that the FLEX equipment does not become a target or source of a seismic interaction from other systems, structures or components. WBN safe shutdown earthquake (SSE) requirements are 0.18g horizontal and 0.12g vertical maximum ground accelerations (References 4 and 5, Sections 2.5.2.4 and 2.5.2.7). For an operating basis earthquake (OBE), the maximum horizontal and vertical ground accelerations are 0.09g and 0.06g, respectively. The FLEX strategies developed for WBN include documentation ensuring that the storage locations and deployment routes meet the FLEX seismic criteria.

In addition to the NEI 12-06 guidance, Near-Term Task Force (NTTF) Recommendation 2.1, Seismic, required that facilities re-evaluate the sites seismic hazard. This seismic hazard re-evaluation requirement has introduced risk to the appropriateness of limiting the design parameters for mitigating strategies equipment robustness to a facilitys original design basis.

Watts Bar subsequently reevaluated its Ground Motion Response Spectra (GMRS) based upon the most recent seismic data and methodologies, and has found that the existing SSE does not envelop the new GMRS at low frequencies for WBN. This liability along with the recognized challenge to perform NTTF Recommendation 2.1 required risk evaluations, via either Seismic Margins Assessment (SMA) or Seismic PRA, is being addressed in the EPRI initiative referred to as the Augmented Approach (EPRI Report 3002000704). The Augmented Approach, in addition to allowing more time to complete the site-specific seismic risk evaluations, also requires plants to address the increase in seismic susceptibility of FLEX equipment. The Augmented Approach ensures that FLEX credited equipment (both currently installed and new) would retain function during and after a beyond design basis seismic event using seismic margins assessment criteria, by calculating a High Confidence of Low Probability Failure (HCLPF) seismic capacity and comparing that to the seismic demand of a Review Level Ground Motion (RLGM), capped to 2 x SSE from 1 to 10 Hz.

NRC endorsement of use of the EPRI Augmented Approach was provided in Reference 25.

Therefore, WBN FLEX credited equipment is designed to achieve a HCLPF capacity based on a seismic RLGM demand equal to 2 x SSE (Reference 26).

E2-3 of 84 Liquefaction TVA has assessed the potential liquefaction of its FLEX deployment routes and determined that the primary and backup deployment routes are not subject to detrimental liquefaction. (Reference 22)

External Flooding:

The types of events evaluated to determine the worst potential flood included (1) probable maximum storm on the total watershed and critical sub-water sheds including seasonal variations and potential consequent dam failures and (2) dam failures in a postulated SSE or OBE with guide specified concurrent flood conditions.

Those safety-related facilities, systems, and equipment located in the containment structure are protected from flooding by the Shield Building structure with those accesses and penetrations below the maximum flood level designed and constructed as watertight elements (References 4 and 5, Section 2.4.6). From References 4 and 5, Section 2.4.3.6, the Diesel Generator (DG) Buildings to the north and the pumping station to the southeast of the main building complex must be protected from flooding to assure plant safety. The DG Buildings operating floors are at elevation 742.0 ft., which are above the maximum computed elevation, including wind wave run-up. Per References 4 and 5, Section 2.4.14.2.3, the Intake Pumping Station (IPS) is designed to retain full functional capability to maintain cooling of plant loads. All equipment required to maintain the plant safely during the flood is either designed to operate submerged, is located above the maximum flood level, or is otherwise protected.

Specific analysis of Tennessee River flood levels resulting from ocean front surges and tsunamis is not required because of the inland location of the plant (References 4 and 5, Section 2.4.6). Snow melt and ice jam considerations are also unnecessary because of the temperate zone location of the plant (References 4 and 5, Sections 2.4.2.2 and 2.4.7). Flood waves from landslides into upstream reservoirs required no specific analysis, in part because of the absence of major elevation relief in nearby upstream reservoirs and because the prevailing thin soils offer small slide volume potential compared to the available detention space in reservoirs (References 4 and 5, Section 2.4.2.2). Seiches pose no flood threats because of the size and configuration of the lake and the elevation difference between normal lake level and plant grade (References 4 and 5, Sections 2.4.2.2 and 2.4.5).

Per References 4 and 5, Section 2.4.2.2, the maximum plant site flood level from any cause is elevation 734.9 ft. This information has been superseded by Reference 9. The maximum plant site flood level from any cause is elevation 739.2 ft. (still reservoir). This elevation would result from the probable maximum storm.

Coincident wind wave activity results in wind waves of up to 2.2 ft. (crest to trough). Run up on the 4:1 slopes approaching the Diesel Generator Building reaches elevation 741.6 ft. Wind wave run up on the critical wall of the Intake Pumping Station reaches elevation 741.7 ft. and wind wave run up on the walls of the Auxiliary, Control and Shield Buildings reaches elevation 741.0 ft. (Reference 9).

In summary, all equipment required to maintain the plant safety during all flooding events including the design basis flood (DBF) is either designed to operate submerged, is located above the maximum flood level, or is otherwise protected. Accordingly, FLEX strategies have been developed for consideration of external flooding hazards. In addition, WBN has developed strategies and procedures for delivery of offsite FLEX equipment during Phase 3 which considers regional impacts from flooding. (Reference 31)

High Wind:

Figures 7-1 and 7-2 from Reference 2 were used for this assessment.

WBN is susceptible to hurricanes as the plant site is within the contour lines shown in Figure 7-1 of Reference

2.

It was determined the WBN site has the potential to experience damaging winds caused by a tornado exceeding 130 mph. Figure 7-2 of Reference 2 indicates a maximum wind speed of 200 mph for Region 1 plants, including Watts Bar. Therefore, high-wind hazards are applicable to the Watts Bar site.

In summary, based on available local data and Figures 7-1 and 7-2 of Reference 2, WBN is susceptible to

E2-4 of 84 severe storms with high winds so the hazard is screened in.

Snow, Ice, and Extreme Cold Per the FLEX guidance all sites should consider the temperature ranges and weather conditions for their site in storing and deploying their FLEX equipment. That is, the equipment procured should be suitable for use in the anticipated range of conditions for the site, consistent with normal design practices.

Applicability of snow and extreme cold:

The Watts Bar Site is located approximately 50 miles northeast of Chattanooga in Rhea County, Tennessee, on the west bank of the Tennessee River at mile 528. The site is approximately 1-1/4 miles south of the Watts Bar Dam and approximately 31 miles north-northeast of the Sequoyah Nuclear Plant (References 4 and 5, Section 2.1.1.1). The approximate site location is given below, from References 4 and 5, Section 2.1.1.1:

LATITUDE (degrees/minutes): 35°36' N LONGITUDE (degrees/minutes): 84°47' W From References 4 and 5, Section 2.3.2.2, mean temperatures at the Watts Bar site have been in the low 40s°F in the winter. Extreme minima temperatures recorded were -20°F at Decatur and -10oF at Chattanooga in the winter.

Outside environment normal operational conditions from Environmental Data Environment Drawing 47E235-36 are given as Average 60, Maximum 95°F and Minimum 13°F. These temperatures were used as a basis in establishing Operational Abnormal temperatures of Maximum 102°F and Minimum 6°F temperatures. This condition could exist for up to 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months per excursion and will occur less than 1% of plant life. (Reference 21).

Reference 2 states plants above the 35th parallel should provide the capability to address the hindrances caused by extreme snow and cold. The Watts Bar site is above the 35th parallel; therefore, the FLEX strategies must consider the hindrances caused by extreme snowfall with snow removal equipment, as well as the challenges that extreme cold temperature may present.

Applicability of ice storms:

The Watts Bar site is not a Level 1 or 2 region as defined by Figure 8-2 of Reference 2; therefore, the FLEX strategies must consider the hindrances caused by ice storms.

In summary, based on the available local data and Figures 8-1 and 8-2 of Reference 2, the Watts Bar site does experience significant amounts of snow, ice, and extreme cold temperatures; therefore, the hazard is screened in.

Extreme Heat:

Per Reference 2, all sites must address high temperatures. Virtually every state in the lower 48 contiguous United States has experienced temperatures in excess of 110°F. Many states have experienced temperatures in excess of 120°F. Sites that should address high temperatures should consider the impacts of these conditions on the FLEX equipment and its deployment. From References 4 and 5, Section 2.3.2.2, mean temperatures at the Watts Bar site can reach the upper 70s°F in the summer. Extreme maxima temperature recorded was 108°F at Decatur, Tennessee and 106°F at Chattanooga, Tennessee in the summer.

Outside environment normal operational conditions from Environmental Data Environment Drawing 47E235-36 are given as Average 60, Maximum 95°F and Minimum 13°F. These temperatures were used as a basis in establishing Operational Abnormal temperatures of Maximum 102°F and Minimum 6°F temperatures. This condition could exist for up to 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months per excursion and will occur less than 1% of plant life. (Reference 21).

Therefore, for selection of FLEX equipment the Watts Bar site considered the site maximum expected temperatures in their specification, storage, and deployment requirements, including ensuring adequate ventilation or supplementary cooling, if required.

E2-5 of 84 Key Site assumptions to implement NEI 12-06 strategies.

Ref: NEI 12-06 Section 3.2.1 Provide key assumptions associated with implementation of FLEX Strategies:

Assumptions are consistent with those detailed in NEI 12-06, Section 3.2.1. Analysis has been performed consistent with the recommendations contained within the Executive Summary of the Pressurized Water Reactor Owners Group (PWROG) Core Cooling Position Paper (Reference 13) and assumptions from that document are incorporated in the plant specific analytical bases.

NEI 12-06 Assumptions The initial plant conditions are assumed to be the following:

x Prior to the event the reactor has been operating at 100 percent rated thermal power for at least 100 days or has just been shut down from such a power history as required by plant procedures in advance of the impending event.

x At the time of the postulated event, the reactor and supporting systems are within normal operating ranges for pressure, temperature, and water level for the appropriate plant condition. All plant equipment is either normally operating or available from the standby state as described in the plant design and licensing basis.

The following initial conditions are to be applied:

x No specific initiating event is used. The initial condition is assumed to be a loss of offsite power (LOOP) at a plant site resulting from an external event that affects the off-site power system either throughout the grid or at the plant with no prospect for recovery of off-site power for an extended period. The LOOP is assumed to affect all units at a plant site.

x All installed sources of design basis emergency on-site ac power and station blackout (SBO) Alternate ac power sources are assumed to be not available and not imminently recoverable.

x Cooling and makeup water inventories contained in systems or structures with designs that are robust with respect to seismic events, floods, and high winds, and associated missiles are available.

x Normal access to the ultimate heat sink (UHS) is lost, but the water inventory in the UHS remains available and robust piping connecting the UHS to plant systems remains intact. The motive force for UHS flow, i.e., pumps, is assumed to be lost with no prospect for recovery.

x Fuel for FLEX equipment stored in structures with designs which are robust with respect to seismic events, floods and high winds and associated missiles, remains available.

x Permanent plant equipment that is contained in structures with designs that are robust with respect to seismic events, floods, and high winds, and associated missiles, are available.

x Other equipment, such as portable ac power sources, portable back up dc power supplies, spare batteries, and equipment for 50.54(hh) (2), may be used provided it is reasonably protected from the applicable external hazards per Sections 5 through 9 and Section 11.3 of NEI 12-06 and has predetermined hookup strategies with appropriate procedures/guidance and the equipment is stored in a relative close vicinity of the site.

x Installed electrical distribution system, including inverters and battery chargers, remain available provided they are protected consistent with current station design.

x No additional events or failures are assumed to occur immediately prior to or during the event, including security events.

x Reliance on the fire protection system ring header as a water source is acceptable only if the header meets the criteria to be considered robust with respect to seismic events, floods, and high winds, and associated missiles.

E2-6 of 84 The following additional boundary conditions are applied for the reactor transient:

x Following the loss of all ac power, the reactor automatically trips and all rods are inserted.

x The main steam system valves (such as main steam isolation valves, turbine stops, atmospheric dumps, etc.), necessary to maintain decay heat removal functions operate as designed.

x Safety/Relief Valves (S/RVs) or Power Operated Relief Valves (PORVs) initially operate in a normal manner if conditions in the reactor coolant system (RCS) so require. Normal valve reseating is also assumed.

x No independent failures, other than those causing the extended loss of alternating current (ac) power (ELAP)/loss of normal access to the ultimate heat sink (LUHS) event, are assumed to occur in the course of the transient.

Sources of expected pressurized water reactor (PWR) reactor coolant inventory loss include:

x Normal system leakage x

Losses from letdown unless automatically isolated or until isolation is procedurally directed x

Losses due to reactor coolant pump (RCP) seal leakage.

The initial spent fuel pool (SFP) conditions are:

x All boundaries of the SFP are intact, including the liner, gates, transfer canals, etc.

x Although sloshing may occur during a seismic event, the initial loss of SFP inventory does not preclude access to the refueling deck around the pool.

x SFP cooling system is intact, including attached piping.

x SFP heat load assumes the maximum design basis heat load for the site.

Containment Isolation Valves:

x It is assumed that the containment isolation actions delineated in current SBO coping capabilities are sufficient.

Assumptions Specific to Watts Bar Site A1. The Auxiliary Feedwater Supply Tank (AFWST) and associated piping are seismically qualified or hardened against missiles and tornados. Watts Bars AFWST is qualified to be robust with respect to high winds and seismic events.

A2. Watts Bar Unit 1 is a mirror image of Unit 2, with only minor differences existing between plants. For this reason, any sections or sketches which are only shown for a single unit would be directly analogous to the other unit.

A3. The design hardened connections added for the purposes of FLEX are protected against external events or are established at multiple and diverse locations.

A4. Flood and seismic re-evaluations pursuant to the Title 10 of the Code of Federal Regulations (10 CFR) 50.54(f) letter of March 12, 2012 are not completed and therefore not assumed in this submittal. As the re-evaluations are completed, appropriate issues will be entered into the corrective action program.

A5. Required staffing levels have been determined consistent with guidance contained in NEI 12-06 for each of the site specific FLEX strategies. Assumed available staffing levels will be determined consistent with NEI 12-01, as described below.

A. Post event time: 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months - No site access. This duration reflects the time necessary to clear roadway obstructions, use different travel routes, mobilize alternate transportation capabilities (e.g.,

private resource providers or public sector support), etc.

B. Post event time: 6 to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months - Limited site access. Individuals may access the site by walking, personal vehicle or via alternate transportation capabilities (e.g., private resource providers or public sector support).

E2-7 of 84 C. Post event time: 24+ hours - Improved site access. Site access is restored to a near-normal status and/or augmented transportation resources are available to deliver equipment, supplies and large numbers of personnel.

A6.Watts Bar has designed and constructed one new storage location to protect portable FLEX equipment against all five external hazards. This location is referred to in this document as the FLEX Equipment Storage Building (FESB). At present, the FESB is located outside the Protected Area boundary but close to access portals. FLEX equipment will be stored/staged in the FESB or inside of site Class I structures.

A7. Instrumentation on FLEX equipment and/or plant process instrumentation will be used to confirm continual performance.

A8. This plan defines strategies capable of mitigating a simultaneous loss of all alternating current (ac) power and loss of normal access to the ultimate heat sink resulting from a beyond-design-basis event by providing adequate capability to maintain or restore core cooling, containment, and SFP cooling capabilities at all units on a site. Though specific strategies have been developed, due to the inability to anticipate all possible scenarios, the strategies are also diverse and flexible to encompass a wide range of possible conditions. These pre-planned strategies developed to protect the public health and safety have been incorporated into the site emergency operating procedures in accordance with established EOP change processes, and their impact to the design basis capabilities of the unit evaluated under 10 CFR 50.59. The plant Technical Specifications contain the limiting conditions for normal unit operations to ensure that design safety features are available to respond to a design basis accident and direct the required actions to be taken when the limiting conditions are not met. The result of the beyond-design-basis event may place the plant in a condition where it cannot comply with certain Technical Specifications and/or with its Security Plan, and as such, may warrant invocation of 10 CFR 50.54(x) and/or 10 CFR 73.55(p). (Reference 12)

Extent to which the guidance, JLD-ISG-2012-01 and NEI 12-06, are being followed.

Identify any deviations to JLD-ISG-2012-01 and NEI 12-06.

Ref: JLD-ISG-2012-01 Ref: NEI 12-06 Section 13.1 Watts Bar Nuclear Plant is using pre-staged 480v (225KVA) and 6900v (3 MW) FLEX Diesel Generators and pre-staged pumps that will be powered through the existing electrical distribution system as a part of the mitigation strategy integrated plan. This was identified as an alternative approach from the strategies identified in NEI 12-06, as endorsed by NRC in JLD-ISG-2012-01, due to reliance on permanently installed plant structures and systems (i.e., electrical distribution system) and components (pre-staged diesel generators and pumps) in lieu of reliance on complete deployment and alignment of portable generators and diesel driven pumps to accomplish an ELAP event mitigation. (References 33 and 34)

Watts Bar Nuclear plans to comply with the guidance in JLD-ISG-2012-01 (Reference 3) and NEI 12-06 (Reference 2) in implementing FLEX strategies for the Watts Bar site except for the alternatives to the guidance as stated above.

E2-8 of 84 Provide a sequence of events and identify any time constraint required for success including the technical basis for the time constraint.

Ref: NEI 12-06 Section 3.2.1.7 JLD-ISG-2012-01 Section 2.1 Describe in this section the sequence of events and technical basis for the time constraint or time sensitive activity identified in A.

See Attachment 1A.

The sequence of events and any associated times constraints are identified below for Watts Bar Reactor Core Cooling and Heat Removal (steam generators available) strategies for FLEX Phases 1 through Phase 3. See A for timeline time constraint or time sensitive activities and Attachment 1B for technical basis support information.

Discussion of sequence of event action items: (Non-Flood Event) 1.

Declare ELAP - ELAP entry conditions can be verified by control room staff and it is validated that emergency diesel generators are not available. This step is time sensitive and needs to occur within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months following the start of the event to provide operators with guidance to perform ELAP actions.

2.

Align and place in service the 225 kva 480v AC Diesel Generators (480v FLEX Generators). This provides charging current to the 125v DC Vital Batteries and ensures 125v DC Vital Battery power (control) and through the Vital Inverters 120v AC Vital Instrument Power (instrument indication).

3.

Verify 125v DC Vital Chargers energized and supplying required load to the 125v DC Vital Batteries.

IF not, THEN complete Extended Load Shed for any Vital Battery not being supplied its required load within 90 minutes (1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months ) following the start of the event. This ensures 8-hour coping time for the 125v DC Vital Batteries. (Reference 30).

4.

Debris Removal (Access) - The earliest need for debris removal access paths is to support alignment of the Low Pressure (LP) FLEX Pumps to the Essential Raw Cooling Water system (ERCW) headers at the IPS. This process will be initiated in order to support FLEX equipment deployment depending on the resources available.

5.

Initiate Damage Assessment - Watts Bar has developed a post event damage assessment procedure. The damage assessment will evaluate and document the condition of plant systems, structures and components (SSCs) after an ELAP event. The assessment is consistent with the guidelines contained in supplement 5 of Reference 16.

6.

Stage and align the LP FLEX pumps (Dominator and Triton) - staged and aligned to take suction from the intake channel with discharge routed to the ERCW FLEX connections inside the IPS. An alternate or additional raw water source could come from the Condenser Circulating Water (CCW) Cooling Tower basin supplying suction to a Dominator LP FLEX Pump with its discharge routed to ERCW FLEX (or B.5.b) connections at the 5th DG Building.

7.

Initiate RCS depressurization and cooldown to commence as soon as possible due to RCP seal failure probability. At rated pressure a potential leakage rate of 20.3 gpm per RCP following the event is possible. At a cold leg pressure of 1485 psig a potential leakage rate of 23.6 gpm per RCP is possible.

(Reference 35 & Reference 55). An RCS cooldown rate of 75-100 °F per hour should be sustained until stabilized at ~ 300 psig Steam Generator (SG) Pressure. Maintain RCS pressure greater than 250 psig to avoid Cold Leg Accumulator (CLA) nitrogen injection into the RCS. The CLAs are maintained at a boron concentration of 3100 - 3300 ppm. Cooldown and depressurization to 300 psig SG pressure should be stabilized within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

8.

Complete 3 MWe FLEX Diesel Generators (6.9KV FLEX Generators), 6.9KV Shutdown Boards and

E2-9 of 84 emergency feeder breakers and 480v Shutdown Board alignment. This is to ensure switching at the EDG building and shutdown board rooms are complete, potential board loading is reduced and interlocks are cleared to allow the emergency feeder breaker to be used to safely power the 6.9KV Shutdown Boards from the 6.9KV FLEX DG.

9.

Energize the 6.9KV Shutdown Boards with the 6.9KV FLEX DGs. Place the following components in service and restore pressurizer level (RCS inventory): Component Cooling System (CCS) Pumps and Safety Injection Pumps (SIPs), as required, to recover and maintain RCS Pressurizer level. The SIPs take suction from the RWST which maintains a boron concentration of between 3100 and 3300 ppm.

10. Once RCS inventory has been restored by SIP operation, calculated boration and required mixing completed and CLAs isolated to ensure against nitrogen injection into the RCS, reduce SG pressure to 160 psig per ECA-0.0.

Note: While the TDAFWP is not anticipated to fail, a secondary source of steam generator makeup can be provided by the MDAFWPs, if required, as soon as the 6.9KV FLEX DGs are in service. The Intermediate Pressure (IP) FLEX pumps will be staged and aligned as soon as feasible (within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months ).

11. Place the following equipment in service, if required: Verify 6.9KV FLEX DG loading between starts.

Auxiliary Air Compressors, Motor Driven Auxiliary Feedwater Pumps (MDAFWPs) and/or Spent Fuel Pool (SFP) Cooling Pump.

Note: 480v FLEX DGs fuel and power line connections could be initiated earlier if resources are available.

12. Complete 480v FLEX DGs power and fuel line connections (between connection points at the EDG Building South wall to connection points at the North wall of Auxiliary Building) and deploy required protection per design requirements. Connections must be complete and verified.

Note: The realignment of ERCW headers are parallel responsibilities for assigned AUOs and ROs. The majority of the realignment will be accomplished by closure of motor operated valves (MOVs) once the Reactor MOV Boards are repowered by the 6.9KV FLEX DGs.

13. Initiate alignment of ERCW headers to ensure cooling water supplied by the LP FLEX pumps are efficiently directed to support FLEX strategies.

14. Stage and align the High Pressure (HP) FLEX pumps (AB elevation 692). The primary suction alignment is from the Refueling Water Storage Tanks (RWST) which maintains a boron concentration of 3100-3300 ppm. The secondary suction alignment is from the Boric Acid Tanks (BATs) which maintain a boron concentration of ~ 6900 ppm. Complete final valve alignment and energizing of the 480v AC power supply to the pumps when required.

15. Stage and align the IP FLEX Pumps at the AFWST as backup for SG makeup (backup to the TDAFWPs and MDAFWPs). Suction is aligned from the AFWST and discharge can be routed to FLEX connections upstream of the TDAFWP Level Control Valves (LCVs) (primary) or MDAFWP LCVs (alternate). These IP FLEX Pumps for non-flood event scenarios are diesel driven.

16. Deploy hoses and spray nozzles to the SFP area as a contingency. Hoses can be routed to supply makeup from FLEX connections on the refuel floor or from the elevation below the refuel floor. This ensures makeup capability prior to the most limiting SFP time when boil off initiates. (Reference 18).

17. Initiate diesel fueled portable FLEX equipment refueling operations within 7 - 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months . The 500 gallon tank on at least one of the FLEX trucks should be filled to support FLEX equipment refueling operations by 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months from event initiation. Diesel powered FLEX equipments onboard fuel supply will require replenishment within 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months from start of operation.

Note: If the Condensate Storage Tanks (CSTs) survive the event they will supply additional clean water reserve per unit to the Auxiliary Feedwater Pumps.

18. The AFWST will be depleted in approximately 15 hours1.736111e-4 days 0.00417 hours 2.480159e-5 weeks 5.7075e-6 months , makeup options will need to be evaluated and

E2-10 of 84 directed. (Reference 46). Potential sources of clean water makeup are the Demineralized Water Storage Tank (DWST), U1 and U2 Primary Water Storage Tanks (PWST) and the Tritiated Water Storage Tank (TWST). If the AFWST is depleted the operating auxiliary feedwater pumps suction will be realigned to the ERCW headers to extend core cooling. The LP FLEX pumps have been aligned to the ERCW headers to provide a raw water input prior to the AFWST depleting. Available raw water in the ERCW headers (without LP FLEX pumps supply) will deplete in 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months for Unit 1 and 4.7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months for Unit 2 (Reference 23).

19. Initiate portable lighting for MCR, Shutdown Board Room and FLEX equipment locations as required.

This is not a time constraint. The MCR and Shutdown Board Rooms are provided with battery backup lighting. Portable lighting for FLEX equipment staging locations could be required. Portable lighting will be available for internal and external service, if required.

20. Complete ERCW header alignments to ensure ERCW pressures and flows for long term FLEX needs within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months of the event.

Note: Doors to rooms where systems and/or components are in service or in operation should be blocked open to facilitate natural ventilation (i.e., Vital Battery rooms, TDAFWP rooms, SIP rooms).

21. The Vital Battery Room and Shutdown Board Room heating, ventilation, and air conditioning (HVAC) study determined that ventilation is not required until 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months into the ELAP event; at which point it can be monitored periodically, if needed (Reference 14).

22. The Main Control Room HVAC study determined that ventilation is not required until 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months into ELAP event; at which point it can be monitored periodically, if needed (Reference 14).

23. The TDAFWP room HVAC study determined that ventilation is not required until 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months into ELAP event; at which point it can be monitored periodically, if needed (Reference 14).

24. Venting of the SFP area will need to be evaluated within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months based on the SFP time when boil off occurs. (Reference 18)

25. A time of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months is assumed for alignment of a mobile water purification system to provide clean water to refill the AFWST. However, cooling water via the ERCW headers is available to be provided indefinitely.

26. Large fuel truck service will need to be established within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . This is based on the depletion of on-site supplies and supplying larger equipment Discussion of action items identified in Attachment 1A Table: (Flood Event)

Note: An ELAP could occur at anytime during flood preparation or a flood event therefore FLEX equipment and strategies must be staged and ready for implementation, if required.

Note: During a Design Basis Flood Mode response, prior to flood waters exceeding plant grade, the EDGs are placed in service supplying plant safety related loads designed for flood mode operations and plant offsite power supplies are removed from service. Plant generation would have been removed from service prior to Flood Mode Stage II entry. Once in Design Basis flood mode operation configuration with EDGs in service supplying safety related loads (ERCW pumps, High Pressure Fire Protection pumps, Spent Fuel Pool Circulation pumps, RCP Thermal Barrier Booster Pumps, Flood Mode Boration System, etc.) the probability of an ELAP event is remote. Design Basis Flood Mode Operations are controlled by AOI-7.01, Maximum Probable Flood.

Note: To assure that FLEX response actions do not impact on design basis flood mode preparations, Watts Bar will pre-stage FLEX Flood Mode equipment based on a 25 year flood warning from TVAs River Operations Forecasting group. Concurrent with full FLEX implementation at Watts Bar, River Operations procedure RvM-SOP-10.05.06, Nuclear Notifications and Flood Warning Procedure, and AOI-7.01, Maximum Probable Flood, have been revised to provide the notification and direct the pre-staging of FLEX equipment. (Reference 44).

E2-11 of 84 Note: The scenario described below assumes an ELAP event occurs post initial flood warning received from TVAs River System Operations and prior to a Stage 1 warning notification. This provides a 27 hour3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months period before flood waters reach grade elevation. This flood preparation time period allows for initial use of the same strategy as a non-flood event for Steps 1-9 for stabilizing the plant and staging FLEX equipment for flood mitigation strategy.

1.

Declare ELAP - ELAP entry conditions can be verified by control room staff and it is validated that emergency diesel generators are not available. This step is time sensitive and needs to occur within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months following the start of the event to provide operators with guidance to perform ELAP actions.

2.

Align and place in service the 225 kva 480vAC Diesel Generators (480v FLEX Generators). This provides charging current to the 125v DC Vital Batteries and ensures 125v DC Vital Battery power (control) and through the Vital Inverters 120v AC Vital Instrument Power (instrument indication).

3.

Verify 125v DC Vital Chargers energized and supplying required load to the 125v DC Vital Batteries.

IF not, THEN complete Extended Load Shed for any Vital Battery not being supplied its required load within 90 minutes (1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months ) following the start of the event. This ensures 8-hour coping time for the 125v DC Vital Batteries. (Reference 30).

4.

Debris Removal (Access) - The earliest need for debris removal access paths is to support alignment of the LP FLEX Pumps to the ERCW headers at the IPS. This process will be initiated in order to support FLEX equipment deployment depending on the resources available.

5.

Damage Assessment - Watts Bar has developed a post event damage assessment procedure. The damage assessment will evaluate and document the condition of plant systems, structures and components (SSCs) after an ELAP event. The assessment will be consistent with the guidelines contained in supplement 5 of Reference 16.

6.

Stage and align the LP FLEX pumps (Dominator and Triton) - staged and aligned to take suction from the intake channel with discharge routed to the ERCW FLEX connections inside the Intake Pumping Station (IPS). An alternate or additional raw water source could come from the Condenser Circulating Water (CCW) Cooling Tower basin supplying suction to a Dominator LP FLEX Pump with its discharge routed to ERCW FLEX (or B.5.b) connection at the 5th DG Building.

7.

Initiate RCS depressurization and cooldown to commence as soon as possible due to RCP seal failure probability. At rated pressure a potential leakage rate of 20.3 gpm per RCP following the event is possible. At a cold leg pressure of 1485 psig a potential leakage rate of 23.6 gpm per RCP is possible.

(Reference 35 & Reference 55). An RCS cooldown rate of 75-100 °F per hour should be sustained until stabilized at ~ 300 psig Steam Generator (SG) Pressure. Maintain RCS pressure greater than 250 psig to avoid Cold Leg Accumulator (CLA) nitrogen injection into the RCS. The CLAs are maintained at a boron concentration of 3100 - 3300 ppm. Cooldown and depressurization to 300 psig SG pressure should be stabilized within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

8.

Align the 3MWe FLEX Diesel Generators (6.9KV FLEX Generators), 6.9KV Shutdown Boards and 480v Shutdown Boards for FLEX DG operation. This is to ensure switching at the EDG building and shutdown board rooms are complete, potential board loading is reduced and interlocks are cleared to allow the emergency feeder breaker to be used to safely power the 6.9KV Shutdown Boards from the 6.9KV FLEX DG.

9.

Energize the 6.9KV Shutdown Boards with the 6.9KV FLEX DGs. Place the following components in service and restore pressurizer level: Component Cooling System Pumps (CCS) and Safety Injection Pumps (SIPs), as required, to recover and maintain RCS Pressurizer level. The SIPs take suction from the RWST which maintains a boron concentration of between 3100 and 3300 ppm.

10. Once RCS inventory has been restored by SIP operation, calculated boration and required mixing completed and CLAs isolated to ensure against nitrogen injection into the RCS reduce SG pressure to

E2-12 of 84 160 psig per ECA-0.0.

Note: While the TDAFWP is not anticipated to fail, a secondary source of steam generator makeup can be provided by the MDAFWPs, if required, as soon as the 6.9KV FLEX DGs are in service.

11. Place the following equipment in service, if required: Verify 6.9KV FLEX DG loading between starts.

Auxiliary Air Compressors, MDAFWPs and/or Spent Fuel Pool (SFP) Cooling Pump.

Note: 480v FLEX DGs fuel and power line connections could be initiated earlier if resources are available.

12. Complete 480v FLEX DGs power and fuel line connections (between connection points at the EDG Building South wall to connection points at the North wall of Auxiliary Building) and deploy required protection per design requirements. Connections must be complete and verified.

Note: The realignment of ERCW headers are parallel responsibilities for assigned AUOs and ROs. The majority of the realignment will be accomplished by closure of MOVs once the Reactor MOV Boards are repowered by the 6.9KV FLEX DGs.

13. Initiate alignment of ERCW headers to ensure cooling water supplied by the LP FLEX pumps are efficiently directed to support FLEX strategies.

Note: The above Design Basis components that are below Probable Maximum Flood (PMF) elevation will be removed from service and protection transitioned to the FLEX strategies prior to flood waters reaching plant grade.

Note: The Auxiliary Feedwater Supply Tank (AFWST) will not be available as a water source once flood water reaches plant grade.

Note: If deployed, verify raw water supply to the ERCW headers from a LP FLEX Pump (Dominator) staged at the CCW Cooling Tower basin, isolate the ERCW FLEX connections inside the IPS and recover the LP FLEX Pumps (Dominator and Triton) staged at the Intake Pumping Station prior to flood waters exceeding their staging location. Relocate these pumps to the staging area north of the EDG Building (above PMF level).

14. Stage and align a complete set of LP FLEX pumps (Dominator and Triton) to take suction from the road just south of the 5th DG Building with discharge available to be routed to the ERCW FLEX (or B.5.b) hose connections at the 5th DG Building. Hoses will remain isolated and pumps out of service until required and flood water level is sufficient for pump suction.

15. Stage and align the HP FLEX Pumps (AB elevation 692) with suction hoses routed from the RWST FLEX connections on AB elevation 692 and discharge hoses routed to the Safety Injection Pump Discharge Header FLEX connection [B Train (primary) or A Train (secondary), AB elevation 692].

Complete final valve alignment and operate these pumps as required to maintain RCS pressurizer level.

16. Stage and align the IP FLEX Pumps (AB elevation 737) with suction hoses routed from the AB elevation 737 ERCW FLEX connections and discharge hoses routed to FLEX connections upstream of the TDAFWP LCVs (primary) (SMSVV elevation 729) or MDAFWP LCVs (alternate) (AB elevation 737). Complete final valve alignment and operate these pumps as required to ensure continuous cooling water supply to the SGs.

17. Deploy hoses and spray nozzles as a contingency for SFP makeup. Hoses can be routed to supply makeup from an AB elevation 757 ERCW - CCS Spool Piece FLEX connection (next to the CCS Surge Tanks) to the SFP area or from an AB elevation 737 FLEX connection to the demineralized water makeup header FLEX connection on AB elevation 737. This ensures makeup capability prior to time when boil off initiates. (Reference 18).

18. Initiate diesel fueled portable FLEX equipment refueling operations within 7 - 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months . The 500 gallon tank on at least one of the FLEX trucks should be filled to support FLEX equipment refueling operations by 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months from event initiation. Diesel powered FLEX equipments onboard fuel supply will require

E2-13 of 84 replenishment within 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months from start of operation.

Note: If the Condensate Storage Tanks (CSTs) survive the event they will supply an additional reserve of water per unit to the Auxiliary Feedwater Pumps until they are removed from service due to flood waters approaching grade level.

19. The AFWST will be depleted in approximately 15 hours1.736111e-4 days 0.00417 hours 2.480159e-5 weeks 5.7075e-6 months for dual unit SG makeup, makeup options will need to be evaluated and directed. (Reference 46). Potential sources of clean water makeup are the Demineralized Water Storage Tank (DWST), U1 and U2 Primary Water Storage Tanks (PWSTs) and the Tritiated Water Storage Tank (TWST). If the AFWST is depleted the operating Auxiliary Feedwater System pumps suction will be realigned to the ERCW headers to extend core cooling. The LP FLEX pumps will be aligned to the ERCW headers to provide a raw water input prior to the AFWST depleting.

Available raw water in the ERCW headers (without LP FLEX pumps supply) would deplete in 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Unit 1 and 4.7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months for Unit 2 (Reference 23).

20. Initiate portable lighting for MCR, Shutdown Board Room and FLEX equipment locations as required.

This is not a time constraint. The MCR and Shutdown Board Rooms are provided with battery backup lighting. Portable lighting for FLEX equipment staging locations could be required. Portable lighting will be available for internal and external service, if required.

21. Complete ERCW header alignments to ensure ERCW pressures and flows for long term FLEX needs within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months of the event.

Note: Doors to rooms where systems and/or components are in service or in operation should be blocked open to facilitate natural ventilation (i.e., Vital Battery rooms, TDAFWP rooms, Safety Injection Pump rooms).

22. The Vital Battery Room and Shutdown Board Room heating, ventilation, and air conditioning (HVAC) study determined that ventilation is not required until 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months into the ELAP event; at which point it can be monitored periodically, if needed (Reference 14).

23. The Main Control Room HVAC study determined that ventilation is not required until 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months into ELAP event; at which point it will be monitored periodically (Reference 14).

24. Venting of the SFP area will need to be evaluated within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months based on the SFP time when boil off occurs (Reference 18).

25. Consideration for mobile water purification systems to provide clean water to refill the AFWST and supply post flood recovery SG makeup operations. However, cooling water via the ERCW headers is available to be provided indefinitely.

26. Large fuel truck service will need to be established to support post flood recovery. This is based on the depletion of on-site supplies and supplying larger equipment.

Watts Bar has prepared procedures for each task, has performed procedure verification and validation for the implementing FLEX Support Instructions (FSIs) and has completed the NTTF Recommendation 9.3 Phase 2 Staffing Analysis. (Reference 50) In addition, the potential impact of FLEX response actions on design basis flood mode preparations has been addressed. TVAs River Systems Operation (RSO) will notify the WBN control room if Watts Bar Hydro instantaneous flow rate reaches 170,000 cfs, which approximates the 25 year flood frequency based upon observed historical flow data. This notification will provide for initiation of preparatory FLEX equipment deployment and mitigation strategy implementation. (Reference 44).

E2-14 of 84 Identify how strategies will be deployed in all modes.

Ref: NEI 12-06 section 13.1.6 Describe how the strategies will be deployed in all modes.

Deployment of FLEX equipment is described for each FLEX function in the subsequent sections below and covers all operating modes. The broad-spectrum deployment strategies do not change for the different operating modes. The deployment strategies from the storage areas to the staging areas are identical and include debris removal, equipment transport, fuel transport, and power sources and requirements. RCS makeup connections are provided for the higher flow rates required during core cooling with SGs unavailable.

Each of these strategies and the associated connection points are described in detail in the subsequent sections.

The electrical coping strategies are the same for all modes. Figures A3-1 through A3-20 show a visual representation of FLEX equipment deployment strategy and FLEX connection options.

Provide a milestone schedule. This schedule should include:

x Modifications timeline o

Phase 1 Modifications o

Phase 2 Modifications o

Phase 3 Modifications x

Procedure guidance development complete o

Strategies o

Maintenance x

Storage plan (reasonable protection) x Staffing analysis completion x

FLEX equipment acquisition timeline x

Training completion for the strategies x

Regional Response Centers operational Ref: NEI 12-06 Section 13.1 The dates specifically required by the order are obligated or committed dates. Other dates are planned dates subject to change.

See attached milestone schedule Attachment 2.

E2-15 of 84 Identify how the programmatic controls will be met.

Ref: NEI 12-06 Section 11 JLD-ISG-2012-01 Section 6.0 NEI 12-02 Revision 1 Section 4 JLD-ISG-2012-03 Equipment associated with these strategies has been procured as commercial equipment with design, storage, maintenance, testing, and configuration control in accordance with NEI 12-06 Revision 0 Section 11.

The unavailability of equipment and applicable connections that directly perform a FLEX mitigation strategy is managed using plant equipment control guidelines developed in accordance with NEI 12-06 Revision 0 Section 11.5.

The unavailability of Spent Fuel Pool (SFP) level instrumentation to perform their intended function is managed using control guidelines developed in accordance with NEI-12-02 Revision 1 Section 4.3.

FLEX Mitigation Strategy required equipment and applicable electrical and mechanical connections and SFP Level Instrumentation unavailability, tracking, return to availability and contingency planning, if required are addressed in the following TVA NPG procedures:

x OPDP - 8, Operability Determination Process and Limiting Conditions for Operation Tracking.

(Reference 47) x NPG - SPP - 07.3, Work Activity Risk Management Process. (Reference 48)

Programs and controls established to assure personnel proficiency in the mitigation of beyond-design-basis events and maintaining FLEX and SFP level instrumentation are developed and maintained in accordance with NEI 12-06 Revision 0 Section 11.6 and NEI 12-02 Revision1 Section 4.1.

The FLEX strategies, SFP level instrumentation and their basis are maintained in an overall program document. Existing plant configuration control procedures have been modified to ensure that changes to the plant design, physical plant layout, roads, buildings, and miscellaneous structures will not adversely impact the approved FLEX strategies nor SFP level instrumentation in accordance with NEI 12-06 Revision 0 Section 11.8 and NEI 12-02 Revision1. Section 4. (Reference 37)

Procedure Guidance The PWROG has generated FLEX Support Guidelines (FSGs) in order to assist utilities with the development of site-specific procedures to cope with an ELAP in a manner compliant with the requirements of Reference NEI 12-06. Watts Bar is a participant in the PWROG project PA-PSC-0965 and has implemented FLEX Support Instructions (FSIs) in a timeline to support the implementation of FLEX for Unit 2 initial licensing (startup) and Unit 1 and Unit 2 licensed operation.

The proposed implementation strategy aligns with the procedure hierarchy described in NEI 12-06 in that actions that maneuver the plant are contained within the typical controlling procedure, and the FLEX Support Instructions (FSIs) are implemented as necessary to maintain the key safety functions of Core Cooling, Spent Fuel Cooling and Containment in parallel with the controlling procedure actions. The overall approach is symptom-based, meaning that the controlling procedure actions and FSIs are implemented based upon actual plant conditions. (Reference 52)

Watts Bar will continue participation in PA-PSC-0965 and will update plant procedures to maintain consistency with the PWROG program. The following FSIs have been developed to support WBNs FLEX mitigation strategies:

x 0-FSI-1, Long Term RCS Inventory Control

E2-16 of 84 x

0-FSI-2, Alternate AFW Suction Source x

0-FSI-3, Alternate Low Pressure Feedwater x

0-FSI-4, DC Bus Management/Load Shed and 480v FLEX DG Alignment x

0-FSI-5.01, Initial Assessment and FLEX Equipment Staging x

0-FSI-5.02, 6900v FLEX DG Startup and Alignment x

0-FSI-5.03, 6.9KV & 480v Shutdown Board Initial FLEX Alignment x

0-FSI-5.04, 6900v FLEX DG Plant Equipment Loading x

0-FSI-5.05, ERCW Alignment for 5000 GPM Portable Diesel Pump (5PDP) x 0-FSI-6, Alternate CST Makeup x

0-FSI-7, Loss of Vital Instrumentation or Control Power x

0-FSI-8, Alternate RCS Boration x

0-FSI-9, Low Decay Heat Temperature Control x

0-FSI-10, Passive RCS Injection Isolation x

0-FSI-11, Alternate SFP Makeup and Cooling x

0-FSI-12, Alternate Containment Cooling x

0-FSI-13, Transition from FLEX Support Instructions Maintenance and Testing The FLEX mitigation equipment has been initially tested (or other reasonable means used) to verify performance conforms to the limiting FLEX requirements. Additionally, Watts Bar has implemented the maintenance and testing template issued by the Electric Power Research Institute (EPRI). The template was developed to meet the FLEX guidelines established in NEI 12-06 Revision Section 11.5.

The SFP level instrumentation has been initially calibrated and tested to verify performance conforms to the requirements of NEI 12-02, Revision1 Section 4.3 and WBNs SFP design. Additionally, WBN has developed maintenance and testing procedures to satisfy the requirements or NEI 12-02, Revision 1 Section 4.2.

Staffing The FLEX strategies documented in the event sequence analysis assume:

x On-site staff are at administrative minimum shift staffing levels, x

No independent, concurrent events, and x

All personnel on-site are available to support site response.

Watts Bar has addressed staffing considerations in accordance with Reference 2. (Reference 50).

Configuration Control Per NEI 12-06 and the Interim Staff Guidance (ISG), the FLEX strategies must be maintained to ensure future plant changes do not adversely impact the FLEX strategies.

Therefore, Watts Bar will maintain the FLEX strategies and basis in an overall program document and has modified existing TVA NPG configuration control procedures to ensure changes to the plant design, physical plant layout, roads, buildings, and miscellaneous structures do not adversely impact the approved FLEX strategies. (Reference 37)

Describe training plan Training plans were developed and presented for plant groups including the emergency response organization (ERO), Fire, Security, Emergency Preparedness (EP), Operations, Engineering and Maintenance. The training plan development was accomplished in accordance with Watts Bar procedures using the Systematic Approach to Training, and has been implemented to ensure that the required Watts Bar staff is trained prior to full implementation of NRC Orders EA-12-049 and EA-12-051.

E2-17 of 84 Describe the Strategic Alliance for FLEX Emergency Response (SAFER)/Regional Response Center (NSRC) plan The nuclear industry has established two National SAFER Response Centers (NSRCs) to support utilities during beyond design basis events. Each NSRC will hold five sets of equipment, four of which will be able to be fully deployed when requested. The fifth set will have equipment that is in a maintenance cycle. Equipment will be moved from the NSRC to a WBN Staging Area, established by the Strategic Alliance for FLEX Emergency Response (SAFER)/NSRC team and TVA. Staging area B is on the WBN site, north of the Emergency Diesel Generator (EDG) Building. Staging area C is the Rockwood Municipal Airport located 34 driving miles from WBN.

Staging area D is the Cleveland Regional Jetport which is 45 driving miles from WBN. Communications will be established between Watts Bar and the SAFER/NSRC team and required equipment moved to the site as needed. First arriving equipment, as established in the SAFER Response Plan for Watts Bar Nuclear (Reference 31), will be delivered to the site within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months from the initial request. Once the equipment arrives onsite WBN will utilize it based on plant conditions and need. Details for activation, delivery and operational capability of the Phase 3 equipment can be found in the SAFER Response Plan for Watts Bar Nuclear. (Reference 31).

TVA has established an agreement with the SAFER/NSRC team in accordance with the requirements of Section 12 of Reference 2.

Notes:

1.

Maintenance and testing, configuration control, training, and regional response center plans have been developed.

E2-18 of 84 Maintain Core Cooling & Heat Removal Determine Baseline coping capability with installed coping1 modifications not including FLEX modifications, utilizing methods described in Table 3-2 of NEI 12-06:

x AFW x

Depressurize SG for Makeup x

Sustained Source of Water Ref: JLD-ISG-2012-01 Sections 2 and 3 PWR Installed Equipment Phase 1 Core Cooling with SGs Available The coping strategy is to remove heat from the RCS by providing cooling water to the four SGs. The plant is assumed to be operating at full power at the start of the event. A station blackout (SBO) occurs to start the scenario and all ac power is assumed to be lost. The TDAFWP will start as designed and provide cooling through the SGs. Initial alignment of the TDAFWP suction is to the AFWST. The AFWST will provide approximately 15 hours1.736111e-4 days 0.00417 hours 2.480159e-5 weeks 5.7075e-6 months of inventory to the suction of the TDAFWPs for each unit before the AFWST is depleted. (Reference 46). If the CSTs survive the event an additional inventory of cooling water would be available (~ 300,000 to 385,000 gallons per unit per CST).

When clean water sources are depleted (AFWST and possibly CSTs, if the CSTs survive the initiating event),

suction flow to the TDAFWPs can be provided by standing water in the ERCW headers. Standing raw water in the ERCW headers would supply an additional 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months for Unit 1 and 4.7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months for Unit 2. (Reference 23).

Core Cooling with SGs Not Available 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. The lowest allowed level in the RCS, when SGs are not available to provide core cooling, is not more than one foot below the vessel flange during the removal of the reactor vessel head.

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 pre-stage FLEX equipment prior to entering a condition where the SGs cannot provide adequate core cooling. (Reference 38).

WBN will follow the guidance contained within the Nuclear Energy Institute (NEI) position paper dated September 18, 2013, entitled Position Paper: Shutdown/Refueling Modes (Agency Wide Documents Access and Management Systems (ADAMS) Accession No. ML13273A514 which NRC has endorsed. (Reference 24).

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Confirm that procedure/guidance exists or will be developed to support implementation.

SBO Emergency Operating Instruction (EOI) ECA-0.0 currently addresses implementation of this strategy. The strategies in ECA-0.0 are supported by the appropriate FSIs for this strategy. (Reference 17).

1 Coping modifications consist of modifications installed to increase initial coping time, i.e., generators to preserve vital instruments or increase operating time on battery powered equipment.

E2-19 of 84 Identify Modifications List modifications and describe how they support coping time.

1. AFWST and connections to Unit 1 and Unit 2 Auxiliary Feedwater System. (DCN 60060, DCN 62324 & DCN 61422) - Provides 500,000 gallons of demineralized water from a seismically qualified source.

2. 8 Hour Battery Coping. (EDC/DCN 60976, DCN 60384 & PIC to DCN 54871) - Increases vital battery coping capability.

3. Backup control stations provide instrument air/nitrogen supplied control capability for the operator to manipulate the SG Atmospheric Relief Valves (ARVs) and Auxiliary Feedwater (AFW) Level Control Valves (LCVs). These stations are located in the shutdown board rooms above the probable maximum flood (PMF) elevation (elevation 757). (DCN 60996

& EDCR 60749)

Key Reactor Parameters

1. SG Wide Range Level or Narrow Range Level with AFW Flow indication

2. SG Pressure

3. AFWST Level RCS instrumentation that is assumed to also be available for this function:

1. Core Exit Thermocouple (CET) Temperature**

2. RCS Hot Leg (HL) Temperature (Thot) if CETs not available

3. RCS Cold Leg (CL) Temperature (Tcold)*

4. RCS Wide Range Pressure

5. Pressurizer Level

6. Reactor Vessel Level Indicating System (RVLIS) (backup to Pressurizer level) - available for up to 27 hours3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months for limiting flood scenario, at which point pressurizer level is available again.

7. Neutron Flux Watts Bar relies on existing installed 125v DC Vital Batteries to power key instrumentation and emergency lighting. A battery coping calculation determined that the battery coping time is 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months . (Reference 30).

This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for Tcold is SG pressure when natural circulation is occurring. This substitution is allowed by guidance provided in Reference 16.

- This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for CETs is RCS HL.

This substitution is allowed by guidance provided in Reference 16.

Watts Bar has developed procedures to read this instrumentation locally, where applicable, using a portable instrument as required by Section 5.3.3 of NEI 12-06. (Reference 32).

Notes:

1. Core cooling strategies are provided for conditions where SGs are available or where SGs are not available but a sufficient RCS vent can be established to support core cooling. This assumption is per the guidance of NEI 12-06 FAQ 2012-19. Other configurations are not considered as these occur at short durations that are exempted per NEI-12-06 Table D.

E2-20 of 84 Maintain Core Cooling & Heat Removal PWR Portable Equipment Phase 2 Provide a general description of the coping strategies using on-site portable equipment including station modifications that are proposed to maintain core cooling. Identify methods and strategy (ies) utilized to achieve this coping time.

Core Cooling with SGs Available Transition to Phase 2 is required before the Turbine Driven Auxiliary Feedwater Pumps suction sources are depleted. The AFWST contains approximately 15 hours1.736111e-4 days 0.00417 hours 2.480159e-5 weeks 5.7075e-6 months of inventory for dual unit operations. (Reference 46)

When clean water sources are depleted (AFWST and possibly CSTs, if the CSTs survive the initiating event),

suction flow to the TDAFWPs can be provided by standing water in the ERCW headers. Standing raw water in the ERCW headers would supply an additional 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months for Unit 1 and 4.7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months for Unit 2. (Reference 23).

If the Condensate Storage Tanks (CSTs) survive the initiating event they would provide additional clean water reserve (~ 300,000 to 385,000 gallons per unit per CST) to the TDAFWPs that would be supplying makeup water to the SGs. Surviving, non-seismic, clean water tanks can also be used to provide makeup to the AFWST using diesel driven deployed transfer pumps, hoses and installed FLEX connections.

To provide an unlimited supply of water for core cooling during Phase 2, LP FLEX Pumps will be staged at the IPS and take suction from the intake channel and discharge to 4 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, if required. An alternate or additional raw water source could come from the Condenser Circulating Water (CCW) Cooling Tower basin supplying suction to a deployed LP FLEX Pump (Dominator)with its discharge routed to ERCW FLEX (or B.5.b) connections located inside the 5th DG Building.

OPTIONS AVAILABLE - NON-FLOOD EVENT:

The Prime Source for Steam Generator (SG) Makeup at Watts Bar Nuclear Plant (WBN) is the Turbine Driven Auxiliary Feedwater Pump (TDAFWP) taking suction from a demineralized water supplied Auxiliary Feedwater Supply Tank (AFWST) and the CSTs, if the non-seismic CSTs survive the initiating event, or from the ERCW system supplying raw water as the ultimate source (safety related), if required.

Option 1. Once the 6.9KV FLEX DGs are available, the Motor Driven Auxiliary Feedwater Pumps (MDAFWPs) (Train A & B) could be placed in service to relieve a TDAFWP, if required. The suction source would be the same as the TDAFWPs.

Option 2. The diesel driven Intermediate Pressure (IP) FLEX pumps are deployed from the FLEX Equipment Storage Building (FESB) and staged on pads next to the AFWST. Pumps suction would be by hose from the AFWST FLEX connections. The discharge is routed by hose to the TDAFWP discharge header FLEX connection in the South Main Steam Valve Vault (MSVV) elevation 729. Optional discharge is to the MDAFWP discharge header FLEX connections on AB elevation 737. (150gpm at 350psig)

Option 3. Once the 6.9KV FLEX DGs are available, the 480v motor driven IP FLEX Pumps pre-staged on AB elevation 737 could be placed in service, if required. Suction would be raw water by hose from the ERCW FLEX connections located on AB elevation 737. The discharge is routed by hose to the TDAFWP discharge header FLEX connection in the South (MSVV) elevation 729. Optional discharge is to the MDAFWP discharge header FLEX connections on AB elevation 737. (150gpm at 350psig) Power supply and control are from the 480v C & A Vent Boards. See Attachment 3, Figures A3-21, A3-23, A3-24 & A3-29 for primary and optional power supplies to the 480v motor driven IP FLEX Pumps.

Option 4. Once the 6.9KV FLEX DGs are available, the 480v motor driven Mode 5 & 6 IP FLEX Pumps pre-staged on AB elevation 692 could be aligned and placed in service as a backup to a failed or unavailable elevation 737 IP FLEX Pump. Suction would be by hose from an ERCW FLEX connection on AB elevation 737. The discharge is routed by hose to the TDAFWP discharge header FLEX connection on elevation 729 in the South (MSVV). Optional discharge is to the MDAFWP discharge header FLEX connections on AB elevation 737. (150gpm at 350psig) Power supply and control are from the 480v C & A Vent Boards. See

E2-21 of 84 Maintain Core Cooling & Heat Removal PWR Portable Equipment Phase 2, Figures A3-21, A3-23 & A3-29 for primary and optional power supplies to the 480v motor driven IP FLEX Pumps.

Option 5. Once the SGs are depressurized to less than 150 psig (~ 105 to 115 psig) per procedure, the deployed from the FESB diesel driven Low Pressure (LP) FLEX Pumps (Triton and Dominators) are capable of supplying raw water to the SGs. For the LP FLEX Pumps staged at the IPS, suction will be supplied from the Tritons floating booster pumps in the intake channel providing positive suction to the LP FLEX Pump (Dominator). The LP FLEX pumps (Dominator ) discharge will routed by hoses to the ERCW headers via ERCW FLEX connections inside the IPS. An alternate or additional raw water source can be made available from a LP FLEX Pump (Dominator) staged at the Unit 2 cooling tower basin. Its suction would come from the basin with discharge hoses routed to ERCW FLEX connections (or B.5.b connections) located inside the 5th DG Building. FLEX hoses would be connected to ERCW FLEX connections on AB elevation 737 and routed to supply raw water to the Unit 1 and 2 TDAFWP discharge header FLEX connections located on elevation 729 in the Unit 1 and Unit 2 South MSVV. Optional discharge is to the MDAFWP discharge header FLEX connections located on AB elevation 737. The LP FLEX pumps are rated at 5000gpm at 150psig.

Further RCS and SG depressurization would be per procedure ensuring appropriate shutdown margin (SDM) throughout the evolution and Cold Leg Accumulators (CLAs) isolation prior to reducing Reactor Coolant System (RCS) pressure below 250 psig.

OPTIONS AVAILABLE - FLOOD EVENT:

An ELAP could occur at any time, therefore Watts Bar will pre-stage FLEX Flood Mode equipment based on a 25 year flood warning from TVAs Division of Water Management, River Systems Operations (RSO)

Branch. TVAs River Systems Operations procedure RvM-SOP-10.05.06, Nuclear Notifications and Flood Warning Procedure, and WBN Operations AOI-7.01, Maximum Probable Flood, will be revised to provide the notification and direct the pre-staging of FLEX equipment. This early notification allows for FLEX equipment to be staged without impacting resources that would be required for design basis flood mode operation preparations. (Reference 44).

Scenario 1 - ELAP Occurs Simultaneous with or early during the Stage 1 Flood Warning preparation time frame:

When TVAs RSO branch determines that a major flood producing storm (area average rainfall of six inches above Chattanooga) is developing they activate their River Operations Emergency Operations Center (REOC) and establish a 3 hour3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months communication between REOC and WBN. When WBN receives this higher level notification they activate the plant Operations Control Center (OCC) and begin planning for design basis flood actions to ensure that required staffing is obtained in advance of a potential Stage 1 Flood Warning. Once a Stage 1 Flood Warning is received from TVAs REOC, the site has a minimum of 27 hours3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months prior to flood water reaching plant grade (elevation 729). During this 27 hour3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months period, if not prior to, based on management decision and anticipatory communication from RSO, the units would be removed from service, cooled down and depressurized, borated to the required shutdown margin and aligned for flood mode operations. The prime source of SG makeup during this 27 hour3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months period would be the TDAFWP taking suction from the AFWST and CSTs, if the non-seismic CSTs survived the initiating event. If clean water became unavailable the suction source would be transferred to raw water supplied to the ERCW headers by the diesel driven LP FLEX Pumps. Backup options available for ensuring makeup to the SGs during this 27 hour3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months period would be the same as for the non-flood event.

Once flood waters exceed plant grade the AB, Control Building and Turbine Building will flood as designed and for a Probable Maximum Flood (PMF) to elevation 739.2. This would result in the Safety Injection Pumps and TDAFW Pumps being ~ 47 feet under water (~37 feet if flood waters are at plant grade elevation) and the MDAFW Pumps being ~ 26 feet underwater at the PMF level inside the AB.

E2-22 of 84 Maintain Core Cooling & Heat Removal PWR Portable Equipment Phase 2 Prior to flood waters exceeding plant grade, SG makeup would be transitioned to an option that would not be impacted by flood waters onsite or inside the AB.

The options available if the AB was flooded are:

Option 1. The 480v motor driven IP FLEX Pumps (submersible operation capable) are pre-staged on AB elevation 737. Pump suction source is raw water routed by hose from the ERCW FLEX connections located on AB elevation 737. Pump discharge is routed by hose to the TDAFWP discharge header FLEX connection on elevation 729 in the South MSVV. Optional discharge is to the MDAFWP discharge header FLEX connections on AB elevation 737. Power supply and control are from the 480v C & A Vent Boards. See, Figures A3-21, A3-23, A3-24 & A3-29 for primary and optional power supplies to the 480v motor driven IP FLEX Pumps. (150gpm at 350psig)

Option 2. Once the SGs are depressurized to less than 150 psig (~105 to 115 psig) per procedure AOI-7.01, Maximum Probable Flood, the diesel driven Low Pressure (LP) FLEX Pumps (Triton and Dominators) are capable of supplying raw water to the SGs. Raw water is supplied from a LP FLEX Pump (Dominator) staged at the Unit 2 cooling tower and taking suction from the basin with its discharge hoses routed to ERCW FLEX connections (or B.5.b connections) located inside the 5th DG Building and/or LP FLEX Pumps (Triton and Dominator) taking suction from flood waters South of the 5th DG Building with pump discharge hoses routed to ERCW FLEX connections (or B.5.b connections) located in the 5th DG Building. A FLEX hose would be connected to an ERCW FLEX connection on AB elevation 737 and routed to the TDAFWP discharge header FLEX connection located on elevation 729 in the South MSVV. Optional discharge is to the MDAFWP discharge header FLEX connections on AB elevation 737. (5000gpm at 150psig)

Scenario 2 - ELAP occurs after the units have been shut down, cooled down and depressurized and borated to a Cold Shutdown-Xenon Free Shutdown Margin condition and aligned for design basis flood mode operation (Stage 1 and Stage 2 flood preparations complete per AOI-7.01, Probable Maximum Flood). Flood waters at or above plant grade:

Note: When an ELAP occurred, SG makeup using raw water supplied by the High Pressure Fire Protection system per design response would be lost.

The options available for this condition are:

Hoses would be previously routed and connected with alignment requiring only valve operation.

Option 1. The 480v motor driven IP FLEX Pumps (submersible operation capable) are pre-staged on AB elevation 737. The pumps suction source is raw water routed by hose from the ERCW FLEX connections located on AB elevation 737. The pumps discharge is routed by hose to the TDAFWP discharge header FLEX connections on elevation 729 in each units South MSVV. Optional discharge is a realignment isolating the failed HPFP system feed and aligning makeup supply from the IP FLEX pump to the MDAFWP discharge header FLEX connections on AB elevation 737. (150gpm at 350psig)

Power supply and control are from the 480v C & A Vent Boards. See Attachment 3, Figures A3-21, A3-23, A3-24 & A3-29 for primary and optional power supplies to the 480v motor driven IP FLEX Pumps.

Option 2. Once the SGs are depressurized to less than 150 psig (~ 105 to 115 psig) per procedure AOI-7.01, Maximum Probable Flood, the diesel driven Low Pressure (LP) FLEX Pumps (Triton and Dominators) are capable of supplying raw water via the ERCW FLEX connections to the SGs. Raw water is supplied by LP FLEX Pumps (Triton and Dominator) taking suction from flood waters South of the 5th DG Building with pump discharge routed by hoses to ERCW FLEX (or B.5.b) connections located in the 5th DG Building. A FLEX hose would be connected to an ERCW FLEX connection on AB elevation 737 and routed to the TDAFWP discharge header FLEX connection located on elevation 729 in the South MSVV. Optional discharge is a realignment aligning makeup supply to the MDAFWP discharge header FLEX connections on AB elevation 737.

E2-23 of 84 Maintain Core Cooling & Heat Removal PWR Portable Equipment Phase 2 Prior to the flood waters exceeding plant grade a LP FLEX Pump (Dominator) staged at the Unit 2 cooling tower and taking suction from the basin with its discharge hoses routed to ERCW FLEX connections (or B.5.b connections) located inside the 5th Diesel Generator (DG) Building would be available to supply raw water to the ERCW headers. (5000gpm at 150psig)

Given the plant structures, system and component (SSC) knowledge and emergency response equipment available onsite, near site or from TVA, INPO or NSRC resources, site Operations, Maintenance and Engineering staff will develop additional options and capabilities for providing a makeup source to the SGs.

The diesel driven IP FLEX Pumps are stored in and will be deployed from the FESB. The 480v motor driven IP FLEX Pumps are pre-staged on AB elevation 737 inside the AB Supply Fan Rooms, the 480v motor driven Mode 5 & 6 IP FLEX Pumps are pre-staged on AB elevation 692 inside the positive displacement (PD) pump rooms. Note that the unit 1 and unit 2 PD pumps located in the rooms are abandoned equipment.

Power supply and control for the IP FLEX Pumps are from the 480v C & A Vent Boards. See Attachment 3, Figures A3-21, A3-23, A3-24 & A3-29 for primary and optional power supplies to the 480v motor driven IP FLEX Pumps.

The deployment paths, staging locations and power supply information for the core cooling and heat removal IP FLEX pumps and associated equipment are provided in Attachment 3.

For non-flood conditions, Watts Bar will gradually transition to a long term core cooling strategy. This will include the use of the LP FLEX pumps on-site to provide a source of cooling water flow to the component cooling system (CCS) heat exchangers. The 6.9 KV FLEX DGs could be used to repower components such as the Auxiliary Air Compressors, MDAFWPs, CCSPs, select ventilation equipment and other components as need and load capability allows.

Core Cooling with SGs Not Available During Cold Shutdown or Refueling Modes, there are many variables that could impact the ability to provide makeup to the RCS and cool the core. With SGs unavailable core cooling is maintained through heat removal from the RCS via coolant boil off. Prior to loss of gravity feed from the RWST, the 480v motor driven Mode 5 & 6 IP FLEX pump must be aligned to take suction from the RWST or another acceptable alternate coolant source and deliver the coolant to the RCS. With SGs unavailable the transition to Phase 2 strategies will be required as inventory is lost from the RCS. Reactor core cooling and heat removal will be provided by using the Mode 5 & 6 IP FLEX pump located on AB elevation 692 to inject water into the RCS via the Safety Injection System FLEX connections. (150gpm at 350psig) Power supply and control are from the 480v C &

A Vent Boards. See Attachment 3, Figures A3-21, A3-23 & A3-29 for primary and optional power supplies.

The connections utilized for RCS Inventory Control/Long-Term Subcriticality will be utilized for the reactor core cooling and heat removal with steam generators not available strategies (Modes 5 and 6). These connections are described in the RCS inventory control section. In addition, a flushing flow of 123 gpm at atmospheric conditions is required at 31 hours3.587963e-4 days 0.00861 hours 5.125661e-5 weeks 1.17955e-5 months in order to preclude the RCS fluid from the incipient boric acid precipitation point. (Reference 20)

WBN will follow the guidance contained within the Nuclear Energy Institute (NEI) position paper dated September 18, 2013, entitled Position Paper: Shutdown/Refueling Modes (Agency Wide Documents Access and Management Systems (ADAMS) Accession No. ML13273A514 which NRC has endorsed. (Reference 24)

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Confirm that procedure/guidance exists or will be developed to support implementation with a description of the procedure / strategy / guideline.

Procedures and guidance to support deployment and implementation, including interfaces to Emergency Operating Instructions (EOIs), special

E2-24 of 84 Maintain Core Cooling & Heat Removal PWR Portable Equipment Phase 2 event procedures, Abnormal Operating Instructions (AOIs), and System Operating Instructions (SOIs), have been developed in accordance with NEI 12-06, Revision 0, Section 11.4. Further, the PWROG has developed generic guidance and Watts Bars strategy aligns with the generic guidance and has considered the Nuclear Steam Supply System (NSSS) specific guidance.

Identify Modifications List modifications necessary for Phase 2

1. Backup control stations provide instrument air/nitrogen supplied control capability for the operator to manipulate the SG Atmospheric Relief Valves (ARVs) and Auxiliary Feedwater (AFW) Level Control Valves (LCVs). These stations are located in the shutdown board rooms above the probable maximum flood (PMF) elevation (elevation 757). (DCN 60996

& EDCR 60749).

2. FLEX connections have been provided on the ERCW headers on Auxiliary Building elevation 737 for supplying water to the elevation 737 IP FLEX pumps. (DCN 60684).

3. The primary FLEX connection point has been provided for SG cooling and is located upstream of the SG LCVs on the TDAFWP discharge line.

(DCN 60683, DCN 61784 & EDCR 60751).

4. The secondary FLEX connection points have been provided for SG cooling and are located upstream of the SG LCVs in both the Train A and Train B MDAFWP discharge piping. A FLEX connection to both trains is needed to ensure feed to all four SGs. (DCN 60683, DCN 61784 &

EDCR 60751).

5. Auxiliary Feedwater Supply Tank (AFWST). (DCN 60060 & DCN 62324).

6. Connections to provide suction capability for Unit 1 AFWPs from the AFWST are complete. (DCN 60060 & DCN 61422).

7. FLEX connections have been provided on the ERCW headers in the IPS for the LP FLEX Pumps to pressurize the ERCW headers during non-flood and flood conditions. (DCN 60684).

8. FLEX connections have been provided on the ERCW headers in the 5th Diesel Generator Building for the LP FLEX Pumps to pressurize the ERCW headers during flood conditions. (DCN 60684).

9. FLEX connections have been provided on the Tritiated Water Storage Tank (TWST), Primary Water Storage Tanks (PWSTs), and Demineralized Water Storage Tank (DWST) to facilitate transfer of water to the AFWST.

(DCN 60683, DCN 59397, DCN 60684, DCN 61784 & EDCR 60993).

10. Pre-staged submersible 480v AC HP & IP (Non-Flood, Flood & Mode 5

& 6) FLEX Pumps and provided power. (DCN 63030).

11. FLEX connections have been provided on the Safety Injection Pumps discharge headers for HP FLEX Pumps RCS makeup. (DCN 60683 &

EDCR 60750).

12. RWST FLEX connections have been provided for HP FLEX pumps or Mode 5 & 6 IP FLEX Pumps suction source. (DCN 60683, DCN 61784

E2-25 of 84 Maintain Core Cooling & Heat Removal PWR Portable Equipment Phase 2

& EDCR 60994).

13. BAT FLEX connection has been provided for an alternate HP FLEX Pump suction supply. (DCN 60684).

14. FLEX Equipment Storage Building (FESB). (DCN 59084).

15. 225kva DGs (480v FLEX DGs). (DCN 59675).

16. 3 MWe DGs (6.9KV FLEX DGs). (DCN 60853).

17. 8 Hour Battery Coping. (EDC/DCN 60976, DCN 60384 & PIC to DCN 54871).

18. Miscellaneous - Installed storage boxes in the AB, IPS and 5th DG Building for hoses, fittings, tools required for implementation. Installed concrete pads and reinforced roads where required for FLEX equipment deployment. (DCN 62889).

Key Reactor Parameters List instrumentation credited or recovered for this coping evaluation.

1. SG Wide Range Level or Narrow Range Level with AFW Flow indication

2. SG Pressure

3. AFWST Level RCS instrumentation that is assumed to also be available for this function:

1. CET Temperature**

2. RCS HL Temperature (Thot) if CETs not available

3. RCS CL Temperature (Tcold)*

4. RCS Wide Range Pressure

5. Pressurizer Level

6. RVLIS (backup to Pressurizer level) - available for up to 27 hours3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months for limiting flood scenario, at which point pressurizer level is available again.

7. Neutron Flux For all instruments listed above the normal power source and the long term power source is the 125v DC Vital Battery.

This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for Tcold is SG pressure when natural circulation is occurring. This substitution is allowed by guidance provided in Reference 16.

- This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for CETs is RCS HL.

This substitution is allowed by guidance provided in Reference 16.

Watts Bar has developed procedures to read this instrumentation locally, where applicable, using a portable instrument as required by Section 5.3.3 of NEI 12-06. (Reference 32)

E2-26 of 84 Storage / Protection of Equipment :

Describe storage / protection plan or schedule to determine storage requirements Seismic The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The FLEX 6.9KV distribution systems have been analyzed to survive 2XSSE HCLPF. The distribution from the FESB to the EDG Building is housed in robust structures and is missile protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is appropriately protected or located within a Class I structure.

The 480v FLEX DGs are pre-staged on the roof of the Auxiliary Building. A protection structure has been built around the DGs, which is designed to the same Seismic Category I requirements as the Auxiliary Building. Seismic input for the design corresponds to the appropriate seismic accelerations at the roof of the Auxiliary Building. This design provides a seismic protection of 2xSSE HCLPF.

Portable equipment required to implement this FLEX strategy will be stored/staged/pre-staged in the FESB, AB, IPS and 5th DG Building which are designed for seismic loading in excess of the minimum requirements of the American Society of Civil Engineers (ASCE) 7-10.

Flooding The 6.9KV FLEX DGs are pre-staged inside the FESB which is located above the PMF elevation. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The distribution system from the FESB to the EDG Building is protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is designed to withstand PMF waters, is appropriately protected or located within a class I structure. The EDG Building is located above the PMF flood level.

The 480v FLEX DGs are pre-staged on the roof of the AB, which is sited in a suitable location that is above the PMF and as such is not susceptible to flooding from any source.

Portable and pre-staged equipment required to implement this FLEX strategy will be maintained in the FESB, AB, IPS and 5th DG Building in suitable locations functionally above the Probable Maximum Flood (PMF) level or pre-flood access and distribution or will be capable of submersible operation.

Severe Storms with High Winds The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The distribution system from the FESB to the EDG Building is protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is appropriately protected or located within a class I structure.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, which is sited in a suitable location that is protected from NRC region 1 tornado, missiles, and velocities as defined in Nuclear Regulatory Commission (NRC) Regulatory Guide 1.76 Revision 1.

Portable equipment required to implement this FLEX strategy will be

E2-27 of 84 maintained in the FESB, AB, IPS and 5th DG Building which are designed to meet or exceed the licensing basis high wind hazard for Watts Bar.

Snow, Ice, and Extreme Cold The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The FESB is provided with a standalone HVAC system to maintain the internal environment between 50 and 100°F up to the point of ELAP.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, and has been evaluated for snow, ice and extreme cold temperature effects and heating has been provided as required to assure no adverse effects on the FLEX equipment.

The FESB has been designed to address snow, ice and extreme cold temperature effects and heating will be provided as required to assure no adverse effects on the FLEX equipment stage/stored there. Equipment stored or staged in the AB, IPS or 5th DG Building are protected from these extremes.

High Temperatures The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The FESB is provided with a standalone HVAC system to maintain the internal environment between 50 and 100°F up to the point of ELAP.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, and has been evaluated for high temperature effects and ventilation is provided as required to assure no adverse effects.

The FESB will be evaluated for high temperature effects and ventilation will be provided as required to assure no adverse effects on the FLEX equipment.

Equipment stored or staged in the AB, IPS or 5th DG Building are protected from high temperature extremes.

Deployment Conceptual Design The figures provided in Attachment 3 show the deployment paths from each of the storage locations to the staging locations.

Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected SGs Available The primary connection for the IP FLEX pumps discharge hoses are located in the South Main Steam Valve Vault (MSVV) elevation 729 upstream of the LCVs on the TDAFWP discharge piping.

For this alignment during non-flood conditions, suction to the Primary connection modifications:

x A tee has been added to the TDAFWP discharge line.

x An isolation valve has been added to the main line upstream of connection.

x An isolation valve has been added to the new branch.

x Storz cap/adapter has been All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The primary connection is located inside the South Main Steam Valve Vault (MSVV). The MSVV is a safety related structure and is protected from all external hazards except flooding. For flood

E2-28 of 84 diesel driven IP FLEX Pumps will be taken from the AFWST or for the elevation 737 480v motor driven IP FLEX Pumps suction would come from the elevation 737 ERCW FLEX connections.

During flood conditions, suction will be taken from the elevation 737 ERCW header FLEX connections. Discharge of the IP FLEX Pumps will be to the connection points shown in, Figure A3-1. The proposed hose routing for the primary connection and the associated equipment staging area can be found in Attachment 3, Figures A3-3 and A3-4.

ERCW connections can be found in Attachment 3, Figures A3-17 and A3-18.

Power supply and control are from the 480v C & A Vent Boards. See Attachment 3, Figures A3-21, A3-23, A3-24 &

A3-29 for primary and optional power supplies to the 480v motor driven IP FLEX Pumps.

added to new branch.

AFWST modifications:

Storz hose connections have been provided with the new AFWST.

ERCW modifications:

For non-flood conditions, one set of LP FLEX pumps will be staged next to the IPS. The existing ERCW piping in the IPS has been modified to add isolation valves with hose connections to allow the ERCW headers to be supplied with raw water by the LP FLEX Pumps. An alternate or additional raw water source could come from the Condenser Circulating Water (CCW) cooling tower basin supplying a suction source to a Dominator LP FLEX Pump with its discharge routed to ERCW FLEX connections (or B.5.b connections) at the 5th DG Building.

For flood conditions, a Dominator LP FLEX Pump taking suction from a CCW Cooling Tower Basin with its discharge routed to the ERCW FLEX (or B.5.b) connections inside the 5th DG Building would be staged and aligned. A second complete set of LP FLEX pumps (Dominator and Triton) will be staged next to the 5th DG Building. The existing ERCW piping inside the 5th DG Building provides FLEX and B.5.b connections (isolation valves with hose connections) to allow the ERCW headers to be supplied with raw water from the LP FLEX Pumps.

To supply water to the suction of the 480v motor driven AB elevation 737 IP FLEX pumps or if required the AB elevation 692 Mode 5 & 6 IP FLEX Pumps, existing ERCW header cleanout ports in the AB on elevation 737 will be utilized. The cleanout ports have been modified to add conditions, procedures will ensure that hoses are connected before flood levels reach the connection.

The connections to the AFWST and ERCW are seismically qualified and missile protected. For connections required during flood conditions, procedures ensure that hoses are connected before flood levels reach the connection.

Connections to other tanks are not protected since the connections are to non-protected tanks and would only be available if the tank survives the event. These connections are used to provide additional capability above the minimum FLEX requirements.

E2-29 of 84 Storz hose connections.

Other tank modifications Storz hose connections with individual isolation valves have been added to the TWST, PWSTs, and DWST for water transfer pump capability to supply clean makeup water to the AFWST.

SGs Available The secondary connection has been located in the AB on Elevation 737 upstream of the LCVs on the MDAFWP discharge piping.

For this alignment, suction will be taken from the AFWST (for the diesel driven IP FLEX Pump) or ERCW headers (for the 480v motor driven FLEX Pumps) and discharged through the IP FLEX Pumps to the connection points shown in Attachment 3, Figure A3-2. The proposed hose routing for the secondary connection and the associated equipment staging area can be found in Attachment 3, Figure A3-3 and Figure A3-5.

ERCW connections can be found in Attachment 3, Figures A3-17 and A3-18.

Power supply and control for the 480v motor driven IP FLEX Pumps are from the 480v C & A Vent Boards. Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-23, A3-24 & A3-29.

Secondary connection modifications:

x Hard piping has been installed between the high pressure fire protection (HPFP) Train A and Train B flood mode supply piping and the MDAFWP Train A and Train B piping which replaced the existing removable spool pieces.

x A tee has been added to this piping.

x Additional isolation valves have been added to either side of the new tees.

x Additional isolation valves have been added on the new branches.

x Storz connections, caps and adapters have been added to these new branches.

AFWST, ERCW, and other tank modifications:

Same as primary.

All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The secondary connections are located inside the AB. The AB is a safety related structure and is protected from all external hazards except flooding. For flood conditions, procedures ensure that hoses are connected before flood levels reach the connection.

The connections to the AFWST and ERCW are seismically qualified and missile protected. For connections required during flood conditions, procedures ensure that hoses are connected before flood levels reach the connection.

Connections to non-seismic tanks are not protected and would only be available if the tank survives the event. These connections are used to provide additional capability above the minimum FLEX requirements.

Steam Generators Not Available When SGs are not available, suction will be taken from the RWST FLEX connections (AB elevation 692) through the Modes 5 & 6 IP FLEX Pumps staged on AB elevation 692 with pump discharge routed to the primary FLEX connections on the Train B Safety Injection Pumps discharge headers.

Primary Connection Modification x

Installed tees or weldolets, x

Added isolation valves x

Added a hose adapters RWST Modifications:

x Installed pipe taps on RWST supply lines to the Refueling Water Purification Pumps on AB elevation 692.

x Added isolation valves on All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The primary connections for the Safety Injection Pump (SIP) Train B discharge header and RWST are located inside the AB. The AB is a safety related structure and is protected from all external hazards except flooding. For flood conditions, procedures ensure that

E2-30 of 84, Figure A3-11.

Power supply to the Mode 5 & 6 IP FLEX Pumps are from the 480v C & A Vent Boards. Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-23 & A3-29.

these connection locations.

x Added Storz adapters with caps on branches.

Safety Injection Pump Discharge Header Modifications FLEX connections on the Safety Injection Pumps discharge Headers for HP FLEX Pumps RCS makeup are located on AB elevation 692.

hoses are connected before flood levels reach the connection.

The RWST connections are located inside the AB on elevation 692. For connections required during flood conditions, procedures ensure that hoses are connected before flood levels reach the connection.

SGs Not Available When SGs are not available, suction will be taken from the RWST FLEX connections (AB elevation 692) through the Mode 5

& 6 IP FLEX Pumps pre-staged on AB elevation 692 with pump discharge routed to the secondary FLEX connections on the Train A Safety Injection Pumps discharge headers., Figure A3-11.

Power supply for the 480v motor driven IP FLEX Pumps is from the 480v C & A Vent Boards.

Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-23 & A3-29.

The secondary Mode 5 & 6 IP FLEX connection modification for steam generators not available is identical to the primary, except for being located on the Safety Injection Pump (SIP) Train B discharge header.

BAT Modification x

Installed tees on discharge lines of BAT A on AB elevation 713.

x Added an isolation valve on the branch.

x Added a Storz adapter with cap on the branch.

All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The secondary FLEX connections for the Safety Injection Pump (SIP)

Train A discharge header and the BAT are located inside the B. The AB is a safety related structure and is protected from all external hazards except flooding. For flood conditions, procedures ensure that hoses are connected before flood levels reach the connection.

The BAT serves as a secondary source and is located inside the AB on elevation 713. For connections required during flood conditions, procedures ensure that hoses are connected before flood levels reach the connection.

Notes:

1.

System modifications are described in the Modifications section above and are illustrated in.

2.

Figures A3-3 through A3-5 in Attachment 3 provides the deployment routes from the staging locations for each IP FLEX pump to the pump suction source and to the primary and secondary connection points on the AFW system.

3.

Figures A3-21 through A3-29 provide FLEX power distribution information for 480v Motor Driven FLEX Pumps.

4.

Core cooling strategies are provided for conditions where SGs are available or where SGs are not available but a sufficient RCS vent could be established to support core cooling. This assumption is per the guidance of NEI 12-06 FAQ 2012-19. Other configurations are not considered as these occur at short durations that are exempted per NEI-12-06 Table D.

E2-31 of 84 Maintain Core Cooling & Heat Removal PWR Portable Equipment Phase 3 Provide a general description of the coping strategies using phase 3 equipment including modifications that are proposed to maintain core cooling. Identify methods and strategy (ies) utilized to achieve this coping time.

Core Cooling with SGs Available For Phase 3, Watts Bar will continue the Phase 2 coping strategies with additional assistance provided from offsite equipment/resources.

The Strategic Alliance for FLEX Emergency Response (SAFER) was selected by the Nuclear Strategic Issues Advisory Committee (NSIAC) to provide offsite National SAFER Response Centers (NSRCs) for the nuclear industry in the United States. The NSRC provides additional capability and redundancy of equipment and resources until power, water, and coolant injection components or systems are restored or commissioned. There are 2 NSRC sites. One located in Memphis, TN and another in Phoenix, AZ. Once the call is made to the NSRC, they will provide ground and/or air transportation of the equipment to WBN staging areas B, C, or D within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . Staging area B is the area north of the EDG building. Staging area C is the Rockwood Municipal Airport located 34 driving miles from WBN. Staging area D is the Cleveland Regional Jetport which is 45 driving miles from WBN. Once the equipment is onsite, WBN will utilize it based on plant conditions and if needed to replace or augment operating FLEX Phase 2 equipment. Additional details for NSRC activation and the equipment that will be provided and delivered can be found in the WBN SAFER playbook, SAFER Response Plan for Watts Bar Nuclear (Reference 31).

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

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Procedures and guidance to support deployment and implementation, including interfaces to Emergency Operating Instructions (EOIs), special event procedures, Abnormal Operating Instructions (AOIs), and System Operating Instructions (SOIs), have been developed in accordance with NEI 12-06, Revision 0, Section 11.4. Further, the PWROG has developed generic guidance and Watts Bar's strategy aligns with the generic guidance and considered the NSSS specific guidance. Finally, Watts Bar included in procedure notification of the NSRC to arrange for delivery and deployment of off-site equipment and sufficient supplies of commodities. TVA NPG has included in CECC EPIP - 3, Operations Duty Specialist Procedure For Alert, Site Area Emergency or General Emergency notification of the NSRC to arrange for delivery and deployment of off-site equipment and sufficient supplies of commodities. (Reference 40).

Identify Modifications Each of the Phase 3 strategies utilize common connections or adapters where required as described for the Phase 2 connections to prevent any compatibility issues with the offsite equipment.

Key Reactor Parameters List instrumentation credited or recovered for this coping evaluation.

1. SG Wide Range Level or Narrow Range Level with AFW Flow indication

2. SG Pressure

3. AFWST Level RCS instrumentation that is assumed to also be available for this function:

1. CET Temperature**

E2-32 of 84 Maintain Core Cooling & Heat Removal PWR Portable Equipment Phase 3

2. RCS HL Temperature (Thot) if CETs not available

3. RCS CL Temperature (Tcold)*

4. RCS Wide Range Pressure

5. Pressurizer Level

6. RVLIS (backup to Pressurizer level) - available for up to 27 hours3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months for limiting flood scenario, at which point pressurizer level is available again.

7. Neutron Flux For all instruments listed above the normal power source and the long-term power source is the 125v DC Vital Battery.

This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for Tcold is SG pressure when natural circulation is occurring. This substitution is allowed by guidance provided in Reference 16.

- This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for CETs is RCS HL.

This substitution is allowed by guidance provided in Reference 16.

Watts Bar has developed procedures to read this instrumentation locally, where applicable, using a portable instrument as required by Section 5.3.3 of NEI 12-06. (Reference 32).

Deployment Conceptual Design Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected A mobile water purification system will enable water from the Tennessee River or other raw water source to be purified. This unit would process the water source and discharge improved quality water to the AFWST.

Each of the Phase 3 strategies will utilize common connections or adapters as described for the Phase 2 connections to prevent any compatibility issues with the offsite equipment.

All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The mobile water purification system will be supplied raw water from the Tennessee River or other raw water source. The discharge connections will be identical to the ones used for water transfer noted in Phase 2. The protection of those connection points is described in the section for Phase 2.

Notes:

1.

Core cooling strategies are provided for conditions where Steam Generators are available or where Steam Generators are not available but a sufficient RCS vent can be established to support core cooling.

This assumption is per the guidance of NEI 12-06 FAQ 2012-19. Other configurations are not considered as these occur at short durations that are exempted per NEI-12-06 Table D.

E2-33 of 84 Maintain RCS Inventory Control PWR Installed Equipment Phase 1:

Determine Baseline coping capability with installed coping2 modifications not including FLEX modifications, utilizing methods described in Table 3-2 of NEI 12-06:

x RCS makeup required (standard design RCP seals) x All Plants Provide Means to Provide Borated RCS Makeup Provide a general description of the coping strategies using installed equipment including modifications that are proposed to maintain RCS inventory control.

This section discusses RCS inventory control and subcriticality issues for conditions where SGs are available.

RCS inventory control and subcriticality issues for conditions where SGs are not available are addressed in the reactor core cooling and heat removal section of this report.

Following the declaration of an ELAP, a plant depressurization and cooldown will be initiated at approximately 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months of ELAP event. Natural circulation is maintained by ensuring adequate RCS inventory.

Watts Bar Unit 1 and Unit 2 have standard Westinghouse RCP seals and given an ELAP event at rated RCS pressure a potential RCP seal leakage rate of 20.3 gpm exists. At a cold leg pressure of 1485 psig a potential leakage rate of 23.6 gpm per RCP is possible. (Reference 35 & Reference 55)

Utilizing WCAP-17601 methodology (Reference 8), References 20 and 49 summarize the limiting plant-specific scenarios for RCS inventory control, shutdown margin, and Mode 5/Mode 6 boric acid precipitation control with respect to the guidelines set forth in NEI 12-06 (Reference 2).

RCS inventory is a significant concern for the ELAP scenario due to the RCP seal design. Timely RCS cooldown and depressurization at 75 to 100°F per hour to ~ 300 psig SG pressure should result in an RCS pressure of ~305 psig and ~ 425°F Tavg. Holding RCS pressure to greater than 250 psig ensures no nitrogen injection into the RCS from Cold Leg Accumulators. RCS makeup is required to compensate for the RCP seal leakage and from shrinkage due to cooldown. For Phase 1 RCS makeup is provided from the Safety Injection System Cold Leg Accumulators. RCP seal leakage would be greatly reduced due to the reduction in RCS pressure.

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Confirm that procedure/guidance exists or will be developed to support implementation SBO EOI ECA-0.0 addresses procedural guidance required for maintaining RCS inventory during Phase 1. (Reference 17) Procedures and guidance to support implementation of a boration strategy, including interfaces to EOIs, special event procedures, AOIs, and SOIs, have been developed in accordance with NEI 12-06, Revision 0, Section 11.4. Further, the PWROG has developed generic guidance and Watts Bars strategy aligns with the generic guidance and considered the NSSS specific guidance.

Identify Modifications List modifications

1. 8 Hour Battery Coping. (EDC/DCN 60976, DCN 60384 & PIC to DCN 54871).

2. Backup control stations provide instrument air/nitrogen supplied control 2 Coping modifications consist of modifications installed to increase initial coping time, i.e., generators to preserve vital instruments or increase operating time on battery powered equipment.

E2-34 of 84 Maintain RCS Inventory Control PWR Installed Equipment Phase 1:

capability for the operator to manipulate the SG Atmospheric Relief Valves (ARVs) and Auxiliary Feedwater (AFW) Level Control Valves (LCVs). These stations are located in the shutdown board rooms above the probable maximum flood (PMF) elevation (elevation 757). (DCN 60996

& EDCR 60749).

3. AFWST and connections to the Auxiliary Feedwater Systems. (DCN 60060, DCN 62324 & DCN 61422).

Key Reactor Parameters List instrumentation credited for this coping evaluation.

1. CET Temperature**

2. RCS HL Temperature (Thot) if CETs not available

3. RCS CL Temperature (Tcold)*

4. RCS Wide Range Pressure

5. Pressurizer Level

6. RVLIS (backup to pressurizer level) - available for up to 27 hours3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months for limiting flood scenario, at which point pressurizer level is available again.

7. Neutron Flux Watts Bar relies on existing installed 125v DC Vital Batteries to power key instrumentation and emergency lighting. A battery coping calculation determined that the battery coping time is 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months . (Reference 30).

This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for Tcold is SG pressure when natural circulation is occurring. This substitution is allowed by guidance provided in Reference 16.

- This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for CETs is RCS HL.

This substitution is allowed by guidance provided in Reference 16.

Watts Bar has developed procedures to read this instrumentation locally, where applicable, using a portable instrument as required by Section 5.3.3 of NEI 12-06. (Reference 32)

Notes: None

E2-35 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 2:

Provide a general description of the coping strategies using installed equipment including modifications that are proposed to maintain RCS inventory control. Identify methods (borated high pressure RCS makeup) and strategy (ies) utilized to achieve this coping time.

This section discusses RCS inventory control and subcriticality issues for conditions where SGs are available.

RCS inventory control and subcriticality issues for conditions where SGs are not available are addressed in the reactor core cooling and heat removal section of this report.

Following the declaration of an ELAP, a plant cooldown will be initiated at approximately 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months of ELAP event. Natural circulation is maintained by ensuring adequate RCS inventory.

Watts Bar Unit 1 and Unit 2 have standard Westinghouse RCP seals and given an ELAP event at rated RCS pressure a potential RCP seal leakage rate of 20.3 gpm exists. At a cold leg pressure of 1485 psig a potential leakage rate of 23.6 gpm per RCP is possible. (Reference 35 & Reference 55)

Utilizing WCAP-17601 methodology (Reference 8) and Westinghouse Calculation Note, CN-SEE-II-13-26, (Reference 20) summarizes the limiting plant-specific scenarios for RCS inventory control, shutdown margin, and Mode 5/Mode 6 boric acid precipitation control with respect to the guidelines set forth in NEI 12-06 (Reference 2).

OPTIONS AVAILABLE - NON-FLOOD EVENT:

Following WBNs Mitigation Strategy, within one hour of the initiating event the units will begin cooldown and depressurization of the RCS to mitigate a potential 20.3 gpm per reactor coolant pump (RCP) leakage from the standard RCP seals at rated RCS pressure. At a cold leg pressure of 1485 psig a potential leakage rate of 23.6 gpm per RCP is possible. (Reference 35 & Reference 55) Timely RCS cooldown and depressurization at 75 to 100°F per hour to ~ 300 psig SG pressure should result in an RCS pressure of ~320 psig and ~ 450°F Tavg.

The first source of RCS makeup is from the Safety Injection System Cold Leg Accumulators (CLAs). As RCS pressure is reduced below the CLA tank pressure this passive safety system will start injecting borated water of 3000-3150 ppm boron concentration into the RCS. This will help compensate for the inventory loss from the RCP seal leakage and RCS shrinkage due to the cooldown. RCS pressure will be held above 250 psig to minimize the possibility of injecting nitrogen from the CLAs into the RCS. RCS cooldown and depressurization should be stabilized within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months of the initiating event. The 6.9KV FLEX Diesel Generators (DGs) will have repowered the 6.9KV Shutdown Boards at approximately 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months allowing operation of the Component Cooling System pumps to support the operation of the Safety Injection Pumps (SIPs). Operation of a SIP in its normal alignment will take suction from the RWST containing ~ 370,000 gallons of demineralized water with a 3100 - 3300 ppm boron concentration and inject into all 4 RCS cold legs.

The SIP operation will provide boration and restore RCS inventory and maintain pressurizer level until the HP FLEX Pump assumed this task. RCP seal leakage would be greatly reduced to ~ 8 to 0.7 gpm per RCP from the reduction in RCS pressure. Approximately 8.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months after the initiating event the pre-staged 480v motor driven High Pressure (HP) FLEX pumps will be available for service. These pumps would be aligned with a suction hose from RWST FLEX connections located on Auxiliary Building elevation 692 and a discharge hose routed to a SIP discharge header FLEX connection on AB elevation 692. An optional suction source is available from a FLEX connection on the Boric Acid Tanks (BAT) (~6900 ppm boron concentration) located on AB elevation 713. Once RCS pressure is reduced, RCP seal leak rate is concurrently reduced and RCS inventory is recovered, the HP FLEX Pump is capable of maintaining RCS inventory. (40gpm at 600psig) The HP FLEX Pumps are fed from and operated from the 480v C & A Vent Boards 1A2-A and 2B2-B. Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-22, A3-23, A3-25, A3-26, A3-27

& A3-28. The spare HP FLEX Pump can also be powered via disconnect switch operation from 480v FLEX DG A.

Option 1. A spare pre-staged HP FLEX Pump is located on AB elevation 692 that can be aligned to replace either units pre-staged HP FLEX Pump, if required. This spare HP FLEX Pump can be powered from either its

E2-36 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 2:

normal feed C & A Vent Board 2B2-B or via disconnect switch operation from 480v FLEX DG A. (40gpm at 600psig) Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-22, A3-23, A3-25, A3-26, A3-27 & A3-28.

Option 2. The diesel driven Intermediate Pressure (IP) FLEX pumps are deployed from the FLEX Equipment Storage Building and normally staged on pads next to the AFWST and aligned as a backup option to the TDAFWP for SG makeup. If required, this pump could be staged and aligned to provide RCS makeup. This option would required a reduction in RCS pressure to ensure adequate injection from the diesel driven IP FLEX Pump. A suction hose would be routed from the RWST FLEX connection located on AB elevation 692 and a discharge hose routed to the SIP discharge header FLEX connection located on AB elevation 692. (150gpm at 350psig)

OPTIONS AVAILABLE - FLOOD EVENT:

An ELAP could occur at any time, therefore Watts Bar will pre-stage FLEX Flood Mode equipment based on a 25 year flood warning from TVAs Division of Water Management, River Systems Operations (RSO) Branch.

TVAs River Systems Operations procedure RvM-SOP-10.05.06, Nuclear Notifications and Flood Warning Procedure and WBN Operations AOI-7.01, Maximum Probable Flood, was revised to provide the notification and WBN will direct the pre-staging of FLEX equipment. This early notification allows for FLEX equipment to be staged without impacting resources that would be required for design basis flood mode Stage 1 and Stage 2 Flood Warning preparations. (Reference 44).

Scenario 1 - ELAP occurs simultaneous with or early during the Stage 1 Flood Warning preparation time frame:

When TVAs RSO branch determines that a major flood producing storm (area average rainfall of six inches above Chattanooga) is developing they activate their River Operations Emergency Operations Center (REOC) and establish a 3 hour3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months communication between REOC and WBN. When WBN receives this higher level notification they activate the plant Operations Control Center (OCC) and begin planning for design basis flood actions to ensure that required staffing is obtained in advance of a potential Stage 1 Flood Warning. Once a Stage 1 Flood Warning is received from TVAs REOC the site has a minimum of 27 hours3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months prior to flood water reaching plant grade (elevation 729). During this 27 hour3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months period, if the units were in either of Modes 1 through 4 they would be shutdown, cooled down and depressurized, borated to the required shutdown margin and aligned for flood mode operations.

Assuming the units were in Mode 1 when the ELAP occurred, the initial source of RCS inventory makeup would be the injection of borated water from the CLAs as the units are depressurized. Once the 6.9KV FLEX DGs repowered the 6.9KV Shutdown Boards and the 480v Shutdown Power distribution system the Safety Injection Pumps will recover RCS inventory taking suction from the RWST. The pre-staged 480v motor driven HP FLEX Pumps (submersible operation capable) would be aligned with suction from the RWST via FLEX connections located on AB elevation 692 and discharge to a FLEX connection located on a SIP discharge header and operated to maintain RCS inventory as required. (40gpm at 600psig)

If the suction supply to a HP FLEX Pump was aligned from the AB elevation 713 BAT FLEX connection it would be transferred to the RWST FLEX connection on AB elevation 692 prior to flood waters reaching grade level.

Once flood waters exceed plant grade the AB, Control Building and Turbine Building will flood as designed and for a Probable Maximum Flood (PMF), flood water will reach elevation 739.2.

Prior to flood waters exceeding plant grade power to the SIPs would be secured at the 6.9KV Shutdown Boards to ensure electrical separation from equipment not designed for AB design basis flood water levels.

The option available if the AB flooded is:

E2-37 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 2:

Note: The suction and discharge hoses to the HP FLEX Pumps would be required to be connected and valves aligned for operation prior to flood waters exceeding plant grade.

Note: If the spare pre-staged HP FLEX Pump was required to replace one of the units HP FLEX Pumps hose and valve alignments must be completed prior to flood waters exceeding plant grade.

Option. The 480v motor driven HP FLEX Pumps (submersible operation capable) pre-staged on AB elevation 692 would be aligned. The HP FLEX Pumps suction source is borated water from the RWST FLEX connections located on AB elevation 692 with the discharge hoses routed to SIP discharge header FLEX connections. (40gpm at 600psig) The ultimate power source for the 480v motor driven HP FLEX Pumps is a 6.9KV FLEX DG through the 480v Shutdown Power distribution network to the 480v C & A Vent Boards.

Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-22, A3-23, A3-25, A3-26, A3-27 & A3-28.

Scenario 2 - ELAP Occurs after the units have been shut down, cooled down and depressurized and borated to a Cold Shutdown-Xenon Free Shutdown Margin condition and aligned for design basis flood mode operation (Stage 1 and Stage 2 flood preparations complete per AOI-7.01, Probable Maximum Flood). Flood waters at or above plant grade:

The option available for this condition is:

Note: If the spare pre-staged HP FLEX Pump was required to replace one of the units HP FLEX Pumps, hose and valve alignments must be completed prior to flood waters exceeding plant grade. Hoses would be previously routed and connected with alignment completed requiring only operation of the HP FLEX Pumps.

Option. The 480v motor driven HP FLEX Pumps (submersible operation capable) pre-staged on AB elevation 692. The suction source is RWST borated water from the RWST FLEX connections located on AB elevation 692 and discharge hoses routed to SIP discharge header FLEX connections located in the SIP rooms on AB elevation 692. (40gpm at 600psig) The ultimate power source for the 480v motor driven IP FLEX is a 6.9KV FLEX DG through the 480v Shutdown Power distribution network to the 480v C & A Vent Boards. Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-22, A3-23, A3-25, A3-26, A3-27

& A3-28.

Given the plant structures, system and component (SSC) knowledge and emergency response equipment available onsite or from TVA, INPO or NSRC resources, site Operations, Maintenance and Engineering staff will develop additional options and capabilities for providing a makeup source to the RCS.

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Procedures and guidance to support deployment and implementation, including interfaces to EOIs, special event procedures, AOIs, and SOIs, will be developed in accordance with NEI 12-06, Revision 0, Section 11.4.

Further, the PWROG has developed generic guidance, and Watts Bars strategy aligns with the generic guidance and considered the NSSS specific guidance.

Identify Modifications List modifications necessary for Phase 2

1. Backup control stations provide instrument air/nitrogen supplied control capability for the operator to manipulate the SG Atmospheric Relief Valves (ARVs) and Auxiliary Feedwater (AFW) Level Control Valves (LCVs).

These stations are located in the shutdown board rooms above the probable maximum flood (PMF) elevation (elevation 757). (DCN 60996 & EDCR 60749)

E2-38 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 2:

2. FLEX connections have been provided on the ERCW headers in the Auxiliary Building elevation 737 for supplying water to the IP FLEX pump.(DCN 60684)

3. The primary FLEX connection point has been provided for SG cooling and is located upstream of the SG LCVs on the TDAFWP discharge line.

(DCN 60683, DCN 61784 & EDCR 60751)

4. The secondary FLEX connection points have been provided for SG cooling and are located upstream of the SG LCVs in both the Train A and Train B MDAFWP discharge piping. A connection to both trains is needed to ensure feed to all four SGs. (DCN 60683, DCN 61784 & EDCR 60751)

5. Auxiliary Feedwater Supply Tank. (DCN 60060 & DCN 62324)

6. FLEX connections to provide suction capability for Unit 1 AFWPs from the AFWST are complete. (DCN 60060 & DCN 61422)

7. FLEX connections have been provided on the ERCW headers in the Intake Pumping Station (IPS) for the LP FLEX Pumps to pressurize the ERCW headers during non-flood and flood conditions. (DCN 60684)

8. FLEX connections have been provided on the ERCW headers in the 5th DG Building for the LP FLEX Pumps to pressurize the ERCW headers during flood conditions. (DCN 60684)

9. FLEX connections have been provided on the Tritiated Water Storage Tank (TWST), Primary Water Storage Tanks (PWSTs), and Demineralized Water Storage Tank to transfer water to the AFWST. (DCN 60684, DCN 60683, DCN 61784 & EDCR 60993)10. FLEX connections have been provided on the Safety Injection Pumps discharge headers for HP FLEX Pumps RCS makeup. (DCN 60683 & EDCR 60750)

11. Pre-staged submersible 480v AC HP & IP (Flood & Mode 5 & 6) FLEX Pumps and provided power. (DCN 63030)12. RWST FLEX connections have been provided for HP FLEX pumps or Mode 5 & 6 IP FLEX Pumps suction source. (DCN 60683, DCN 61784 & EDCR 60994)

13. BAT FLEX connection has been provided for an alternate HP FLEX Pump suction supply. (DCN 60684)

14. FLEX Equipment Storage Building (FESB). DCN 59084)

15. 225kva DGs (480v FLEX DGs). (DCN 59675)

16. 3 MWe DGs (6.9KV FLEX DGs) (DCN 60853)

17. 8 Hour Battery Coping. (EDC/DCN 60976, DCN 60384 & PIC to DCN 54871)

18. Miscellaneous - Installed storage boxes in the AB, IPS and 5th DG Building for hoses, fittings, tools required for implementation. Installed concrete pads and reinforced roads where required for FLEX equipment deployment. (DCN 62889)

E2-39 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 2:

Key Reactor Parameters List instrumentation credited or recovered for this coping evaluation.

1. CET Temperature**

2. RCS HL Temperature (Thot) if CETs not available

3. RCS CL Temperature (Tcold)*

4. RCS wide range pressure

5. RCS Passive Injection Level

6. Pressurizer Level

7. RVLIS (backup to Pressurizer level) - available for up to 27 hours3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months for limiting flood scenario, at which point pressurizer level is available again.

8. Neutron Flux For all instruments listed above the normal power source and the long-term power source is the 125v DC Vital Battery.

This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for Tcold is SG pressure when natural circulation is occurring. This substitution is allowed by guidance provided in Reference 16.

- This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for CETs is RCS HL.

This substitution is allowed by guidance provided in Reference 16.

Watts Bar has developed procedures to read this instrumentation locally, where applicable, using a portable instrument as required by Section 5.3.3 of NEI 12-06. (Reference 32)

Storage / Protection of Equipment:

Describe storage / protection plan or schedule to determine storage requirements Seismic The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The FLEX 6.9KV distribution systems have been analyzed to survive 2XSSE HCLPF. The distribution from the FESB to the EDG Building is housed in robust structures and is missile protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is appropriately protected or located within a Class I structure.

The 480v FLEX DGs are pre-staged on the roof of the Auxiliary Building. A protection structure has been built around the DGs, which is designed to the same Seismic Category I requirements as the Auxiliary Building. Seismic input for the design corresponds to the appropriate seismic accelerations at the roof of the Auxiliary Building. This design provides a seismic protection of 2xSSE HCLPF.

Portable equipment required to implement this FLEX strategy will be stored/staged/pre-staged in the FESB, AB, IPS and 5th DG Building which are designed for seismic loading in excess of the minimum requirements of the American Society of Civil Engineers (ASCE) 7-10.

Flooding The 6.9KV FLEX DGs are pre-staged inside the FESB which is located above the PMF elevation. The FESB is a formidable structure designed and built to

E2-40 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 2:

withstand 2X SSE HCLPF and 360 MPH winds. The distribution system from the FESB to the EDG Building is protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is designed to withstand PMF waters, is appropriately protected or located within a class I structure. The EDG Building is located above the PMF flood level.

The 480v FLEX DGs are pre-staged on the roof of the AB, which is sited in a suitable location that is above the PMF and as such is not susceptible to flooding from any source.

Portable and pre-staged equipment required to implement this FLEX strategy will be maintained in the FESB, AB, IPS and 5th DG Building in suitable locations functionally above the Probable Maximum Flood (PMF) level or are capable of submersible operation. Equipment required for this function will be stored so that it can be deployed prior to any concerns with flooding.

Severe Storms with High Winds The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The distribution system from the FESB to the EDG Building is protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is appropriately protected or located within a class I structure.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, which is sited in a suitable location that is protected from NRC region 1 tornado, missiles, and velocities as defined in Nuclear Regulatory Commission (NRC) Regulatory Guide 1.76 Revision 1.

Portable equipment required to implement this FLEX strategy will be maintained in the FESB, AB, IPS and 5th DG Building which are designed to meet or exceed the licensing basis high wind hazard for Watts Bar.

Snow, Ice, and Extreme Cold The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The FESB is provided with a standalone HVAC system to maintain the internal environment between 50 and 100°F up to the point of ELAP.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, and has been evaluated for snow, ice and extreme cold temperature effects and heating has been provided as required to assure no adverse effects on the FLEX equipment.

The FESB has been designed to address snow, ice and extreme cold temperature effects and heating will be provided as required to assure no adverse effects on the FLEX equipment stage/stored there. Equipment stored or staged in the AB, IPS or 5th DG Building are protected from these extremes.

High Temperatures The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360

E2-41 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 2:

MPH winds. The FESB is provided with a standalone HVAC system to maintain the internal environment between 50 and 100°F up to the point of ELAP.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, and has been evaluated for high temperature effects and ventilation is provided as required to assure no adverse effects.

The FESB will be evaluated for high temperature effects and ventilation will be provided as required to assure no adverse effects on the FLEX equipment.

Equipment stored or staged in the AB, IPS or 5th DG Building are protected from high temperature extremes.

Deployment Conceptual Modification (Attachment 3 contains Conceptual Sketches)

Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected The primary RCS makeup FLEX connection is located on the SIP Train B discharge line, in the SIP room at elevation 692.

For this alignment, suction will be taken from the RWST and discharged through the HP FLEX pumps to the FLEX connection points shown in, Figure A3-6. The proposed hose routing for the primary connection and the associated equipment can be found in Attachment 3, Figures A3-8 through A3-10.

The power supply and control for the 480v motor driven HP FLEX Pumps are the 480v C &

A Vent Boards. Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-22, A3-23, A3-25, A3-26, A3-27 & A3-28.

During Mode 5 and 6 with SGs unavailable, suction will be taken from the RWST FLEX connections and discharged through the Mode 5 & 6 IP Primary Connection Modification x

Installed tees or weldolets, x

Added isolation valves x

Added hose adapters RWST Modifications:

The RWST FLEX connections are located on elevation 692 in the Auxiliary Building.

Safety Injection Pum p Discharge Header Modifications The FLEX connections on the SIPs discharge Headers for HP FLEX Pumps RCS makeup are located on AB elevation 692.

All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The primary FLEX connection and RWST connection are located inside the Auxiliary Building. The AB is a safety related structure and is protected from all external hazards except flooding.

The RWST FLEX connections are seismically qualified and missile protected.

E2-42 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 2:

FLEX pumps (pre-staged in AB elevation 692. near the primary connection point).

Power supply for the 480v motor driven Mode 5 & 6 IP FLEX Pumps is from the 480v C & A Vent Boards. Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-23 & A3-29.

The secondary RCS makeup FLEX connection will be on the SIP Train A discharge line, in the SIP room at elevation 692.

For this alignment, suction will be taken from the RWST and discharged through the HP FLEX pumps to the connection points shown in Attachment 3, Figure A3-6. The proposed hose routing for the secondary RCS FLEX connection and the associated equipment can be found in Attachment 3, Figure A3-8.

The secondary HP FLEX Pump suction source is the Boric Acid Tanks (BATs) shown on, Figures A3-9 and A3-10.

The power supply and control for the 480v motor driven HP FLEX Pumps are the 480v C &

A Vent Boards. Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-22, A3-23, A3-25, A3-26, A3-27 & A3-28.

During Mode 5 and 6 with SGs unavailable, suction will be taken from the RWST and discharged through the Mode 5 and 6 IP FLEX pumps pre-staged on elevation 692 in the Auxiliary Building. Figure A3-

11.

The secondary FLEX connection modification is identical to the primary, except for being located on SIP Train A discharge.

BAT Modification x

Installed tee on discharge line of BAT A on AB elevation 713.

x Added an isolation valve on the branch.

x Added a Storz adapter with cap on branch.

Safety Injection Pump Discharge Header Modifications The FLEX connections on the SIPs discharge headers for HP FLEX Pumps RCS makeup are located on AB elevation 692.

All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The secondary connection and BAT FLEX connection are located inside the AB. The AB is a safety related structure and is protected from all external hazards except flooding.

The RWST connections are seismically qualified and missile protected. For connections required during flood conditions, procedures ensure that hoses are connected before flood levels reach the connection.

E2-43 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 2:

Power supply for the 480v motor driven Mode 5 & 6 IP FLEX Pumps is from the 480v C & A Vent Boards. Power supply routing and options can be found in Attachment 3, Figures A3-21, A3-23 & A3-29.

Notes:

1.

System modifications are described in the Modifications section above and are illustrated in.

2.

N+1 HP FLEX Pumps are pre-staged in the Auxiliary Building.

3., Figures A3-8 through A3-10 provides the deployment routes from the pre-staged locations for each HP FLEX Pump to the pumps suction piping and to the primary and secondary connection points on the RCS connected systems.

4.

Attachment 3, Figures A3-21 through A3-29 provide FLEX power distribution information for 480v motor driven FLEX Pumps.

E2-44 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 3:

Provide a general description of the coping strategies using phase 3 equipment including modifications that are proposed to maintain RCS Inventory Control. Identify method (borated high pressure RCS makeup) and strategy (ies) utilized to achieve this coping time.

This section discusses RCS inventory control and subcriticality issues for conditions where SGs are available.

RCS inventory control and subcriticality issues for conditions where SGs are not available are addressed in the reactor core cooling and heat removal section of this report.

Reactor level and sub-criticality is adequately maintained via the Phase 2 strategy.

For Phase 3, Watts Bar will continue the Phase 2 coping strategies with additional assistance provided from offsite equipment/resources. The Strategic Alliance for FLEX Emergency Response (SAFER) was selected by the Nuclear Strategic Issues Advisory Committee (NSIAC) to provide offsite National SAFER Response Centers (NSRC) for the nuclear industry in the United States. The NSRC provides additional capability and redundancy of equipment and resources until power, water, and coolant injection components or systems are restored or commissioned. There are 2 NSRC sites. One located in Memphis, TN and another in Phoenix, AZ.

Once the call is made to the NSRC, they will provide ground and/or air transportation of the equipment to WBN staging areas B, C, or D within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . Staging area B is the area north of the EDG building. Staging area C is the Rockwood Municipal Airport located 34 driving miles from WBN. Staging area D is the Cleveland Regional Jetport which is 45 driving miles from WBN. Once the equipment is onsite WBN will utilize it based on plant conditions and if needed to replace or augment operating FLEX Phase 2 equipment.

Additional details for NSRC activation and the equipment that will be provided and delivered can be found in the WBN SAFER playbook, SAFER Response Plan for Watts Bar Nuclear (Reference 31).

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Procedures and guidance to support deployment and implementation, including interfaces to EOIs, special event procedures, AOIs, and SOIs, has been developed in accordance with NEI 12-06, Revision 0, Section 11.4.

Further, the PWROG has developed generic guidance, and Watts Bar's strategy aligns with the generic guidance and considered the NSSS specific guidance. TVA NPG has included in CECC EPIP - 3, Operations Duty Specialist Procedure For Alert, Site Area Emergency or General Emergency notification of the NSRC to arrange for delivery and deployment of off-site equipment and sufficient supplies of commodities. (Reference 40)

Identify Modifications Each of the Phase 3 strategies will utilize common connections or adapters as described for the Phase 2 connections to prevent any compatibility issues with the offsite equipment.

Key Reactor Parameters List instrumentation credited or recovered for this coping evaluation.

1. CET Temperature**

2. RCS HL Temperature (Thot) if CETs not available

3. RCS CL Temperature (Tcold)*

4. RCS wide range pressure

5. RCS Passive Injection Level

6. Pressurizer Level

7. RVLIS (backup to Pressurizer level) - available for up to 27 hours3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months for limiting flood scenario, at which point pressurizer level is available again.

8. Neutron Flux

E2-45 of 84 Maintain RCS Inventory Control PWR Portable Equipment Phase 3:

For all instruments listed above the normal power source and the long-term power source is the 125v DC Vital Battery.

This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for Tcold is SG pressure when natural circulation is occurring. This substitution is allowed by guidance provided in Reference 16.

- This instrumentation is available until flood water enters the auxiliary instrument room. The potential validating indicator for CETs is RCS HL.

This substitution is allowed by guidance provided in Reference 16.

Watts Bar has developed procedures to read this instrumentation locally, where applicable, using a portable instrument as required by Section 5.3.3 of NEI 12-06. (Reference 32)

Deployment Conceptual Modification (Attachment 3 contains Conceptual Sketches)

Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected A mobile water purification system provided by SAFER/NSRC will allow demineralized water makeup to the AFWST and/or for other uses.

Each of the Phase 3 strategies will utilize common connections or adapters as described for the Phase 2 connections to prevent any compatibility issues with the offsite equipment.

All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The discharge connection points are identical to the ones used for Phase 2.

The protection of those connection points is described in the section for Phase 2 for RCS Inventory Control.

Notes: None

E2-46 of 84 Maintain Containment PWR Installed Equipment Phase 1:

Determine Baseline coping capability with installed coping3 modifications not including FLEX modifications, utilizing methods described in Table 3-2 of NEI 12-06:

x Containment Spray x

Hydrogen igniters Provide a general description of the coping strategies using installed equipment including modifications that are proposed to maintain containment.

Watts Bar has performed a containment evaluation based on the boundary conditions described in Section 2 of NEI 12-06. Based on the results of this evaluation, required actions to ensure maintenance of containment integrity and required instrumentation function have been developed. (Reference 41)

There are no phase 1 actions required at this time that need to be addressed.

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Procedures and guidance to support implementation of this strategy, including interfaces to EOIs, special event procedures, AOIs, and SOIs, have been developed in accordance with NEI 12-06, Revision 0, Section 11.4. Further, the PWROG has developed generic guidance, and Watts Bars strategy aligns with the generic guidance and considered the NSSS specific guidance.

Identify Modifications

1. 8 Hour Battery Coping. (EDC/DCN 60976, DCN 60384 & PIC to DCN 54871).

Key Containment Parameters List instrumentation credited for this coping evaluation.

1. Containment Pressure*

2. Containment Temperature**

Watts Bar relies on existing installed 125v DC Vital Batteries to power key instrumentation and emergency lighting. A battery coping calculation determined that the battery coping time is 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months . (Reference 30).

- This instrumentation is only available until flood water enters the technical support center (TSC) inverter or station battery rooms.

Watts Bar has developed a procedure to read this instrumentation locally, where applicable, using a portable instrument as required by Section 5.3.3 of NEI 12-06. (Reference 32)

Notes: None 3 Coping modifications consist of modifications installed to increase initial coping time, i.e., generators to preserve vital instruments or increase operating time on battery powered equipment.

E2-47 of 84 Maintain Containment PWR Portable Equipment Phase 2:

Provide a general description of the coping strategies using on-site portable equipment including modifications that are proposed to maintain containment. Identify method (hydrogen igniters) and strategy (ies) utilized to achieve this coping time.

Watts Bar has performed a containment analysis based on the boundary conditions described in Section 2 of NEI 12-06. (Reference 41). Based on the results of this analysis, required actions to ensure maintenance of containment integrity and required instrumentation function have been developed. (Reference 53).

At approximately 60 hours6.944444e-4 days 0.0167 hours 9.920635e-5 weeks 2.283e-5 months into the event the containment analysis recommends a 10 minute run of a Containment Air Return Fan. This operation ensures ice condenser doors open and enhanced flow through the ice condenser and benign containment conditions for a significant period of time past T+72 hours. (Reference 41 and Reference 53).

The onsite 6.9KV FLEX DGs also provide the ability to recover operation of Lower Compartment Coolers (LCCs) for containment temperature control, if required. Cooling water would be provided to the LCCs by deployed diesel powered LP FLEX Pumps feeding the ERCW system headers and alignment of the ERCW system to maximize efficient usage of available cooling water. (Reference 53 and Reference 54).

Additionally, the 6.9KV FLEX DGs can power the hydrogen igniters through the 480v shutdown power distribution system, if required. The 480v FLEX DGs discussed in the safety functions support section can also be aligned to provide power to the hydrogen igniter supply transformers, if required.

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Procedures and guidance to support deployment and implementation, including interfaces to EOIs, special event procedures, AOIs, and SOIs, has been developed in accordance with NEI 12-06, Revision 0, Section 11.4. Further, the PWROG has developed generic guidance, and Watts Bars strategy aligns with the generic guidance and considered the NSSS specific guidance.

Identify Modifications

1. FLEX Equipment Storage Building (FESB). DCN 59084).

2. FLEX connections have been provided on the ERCW headers in the IPS for the LP FLEX Pumps to pressurize the ERCW headers during non-flood and flood conditions. (DCN 60684).

3. FLEX connections have been provided on the ERCW headers in the 5th DG Building for the LP FLEX Pumps to pressurize the ERCW headers during flood conditions. (DCN 60684).

4. 225kva DGs (480v FLEX DGs) (DCN 59675).

5. 3 MWe DGs (6.9KV FLEX DGs) (DCN 60853).

6. Miscellaneous - Installed storage boxes in the IPS and 5th DG Building for hoses, fittings, tools required for implementation. Installed concrete pads and reinforced roads where required for FLEX equipment deployment.

(DCN 62889).

Key Containment Parameters List instrumentation credited or recovered for this coping evaluation.

1. Containment Pressure*

2. Containment Temperature**

For this instrumentation, the normal power source and the long-term power source are the 125v DC Vital Battery.

- This instrumentation is only available until flood water enters the TSC inverter or station battery rooms.

E2-48 of 84 Maintain Containment Storage / Protection of Equipment:

Describe storage / protection plan or schedule to determine storage requirements Seismic The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The distribution system from the FESB to the EDG Building is protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is appropriately protected or located within a class I structure.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, which is designed to the same Seismic Category I requirements as the AB. Seismic input for the design corresponds to the appropriate seismic accelerations at the roof of the AB.

This design provides a seismic protection of 2xSSE HCLPF.

Flooding The 6.9KV FLEX DGs are pre-staged inside the FESB which is located above the PMF elevation. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The distribution system from the FESB to the EDG Building is protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is designed to withstand PMF waters, is appropriately protected or located within a class I structure.

The 480v FLEX DGs are pre-staged on the roof of the AB, which is sited in a suitable location that is above the PMF and as such is not susceptible to flooding from any source.

Severe Storms with High Winds The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The distribution system from the FESB to the EDG Building is protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is appropriately protected or located within a class I structure.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, which is sited in a suitable location that is protected from NRC region 1 tornado, missiles, and velocities as defined in Nuclear Regulatory Commission (NRC) Regulatory Guide 1.76 Revision 1.

Snow, Ice, and Extreme Cold The 6.9KV FLEX DGs are pre-staged inside the FESB. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The FESB is provided with an HVAC system to maintain the internal environment between 50 and 100°F up to the point of ELAP.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, and has been evaluated for snow, ice and extreme cold temperature effects and heating has been provided as required to assure no adverse effects on the FLEX equipment.

High Temperatures The FESB will be evaluated for high temperature effects and ventilation will be provided as required to assure no adverse effects on the FLEX equipment.

The FESB will have a standalone HVAC system to maintain the internal environment between 50 and 100°F up to the point of ELAP.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, and has been evaluated for high temperature effects and ventilation is provided as required to assure no adverse effects on the FLEX equipment.

E2-49 of 84 Deployment Conceptual Modification (Attachment 3 contains Conceptual Sketches)

Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected The hydrogen igniters can be repowered by the 6.9KV FLEX DGs that are pre-staged inside the FESB or by the 480v FLEX DGs that are pre-staged on the roof of the AB.

Additionally, repowering the 6.9KV and 480v Shutdown Electrical distribution system provides the ability to operate Containment Air Return Fans and other containment ventilation components (i.e., Lower Compartment Coolers), if required.

The 6.9KV FLEX DGs can provide power to the Hydrogen Igniter transformers via the normal shutdown power distribution system which powers the 480v portions of the system. (DCN 60853).

The 480v FLEX DGs that are pre-staged on the roof of the AB can also be aligned to power the Hydrogen Igniter transformers, if required. (DCN 59675).

The protection structures for the 6.9KV FLEX DGs and the 480v FLEX DGs and the diverse power distribution system are protected from the five external hazards, as described in this section.

Notes: None

E2-50 of 84 Maintain Containment PWR Portable Equipment Phase 3:

Provide a general description of the coping strategies using Phase 3 equipment including modifications that are proposed to maintain containment. Identify method (hydrogen igniters) and strategy (ies) utilized to achieve this coping time.

Watts Bar has performed a containment evaluation based on the boundary conditions described in Section 2 of NEI 12-06. Based on the results of this evaluation, required actions to ensure maintenance of containment integrity and required instrumentation function have been developed. (Reference 41)

The hydrogen igniters can be powered through the 6.9KV Shutdown Power and 480v Shutdown Power distribution systems. (See PWR Portable Equipment Phase 3 Medium Voltage and Low Voltage Backup listings).

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Procedures and guidance to support deployment and implementation, including interfaces to EOIs, special event procedures, AOIs, and SOIs, have been developed in accordance with NEI 12-06, Revision 0, Section 11.4.

Further, the PWROG has developed generic guidance, and Watts Bars strategy aligns with the generic guidance and considered the NSSS specific guidance. TVA NPG has included in CECC EPIP - 3, Operations Duty Specialist Procedure For Alert, Site Area Emergency or General Emergency notification of the NSRC to arrange for delivery and deployment of off-site equipment and sufficient supplies of commodities. (Reference 40).

Identify Modifications The same modification as Phase 2 applies for Phase 3.

Key Containment Parameters List instrumentation credited or recovered for this coping evaluation.

1. Containment Pressure*

2. Containment Temperature**

For this instrumentation, the normal power source and the long-term power source is the 125v DC Vital Battery.

Watts Bar has a procedure to read this instrumentation locally, if required, using a portable instrument as required by Section 5.3.3 of NEI 12-06.

(Reference 32).

- This instrumentation is only available until flood water enters the TSC inverter or station battery rooms.

Deployment Conceptual Modification (Attachment 3 contains Conceptual Sketches)

Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected The same modification, as Phase 2 applies for Phase 3.

The same modification, as Phase 2 applies for Phase 3.

All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis safe shutdown earthquake (SSE) protection requirements. The same modification, as Phase 2 applies for Phase 3.

Notes: None

E2-51 of 84 Maintain Spent Fuel Pool Cooling PWR Installed Equipment Phase 1:

Determine Baseline coping capability with installed coping4 modifications not including FLEX modifications, utilizing methods described in Table 3-2 of NEI 12-06:

x Makeup with Portable Injection Source Provide a general description of the coping strategies using installed equipment including modifications that are proposed to maintain spent fuel pool cooling. Identify methods (makeup via portable injection source) and strategy(ies) utilized to achieve this coping time.

Reference 18 summarizes that there will be no significant volume lost from the SFP due to sloshing. A small range of critical damping factors were investigated and it was shown that the critical damping factor had no influence on the amount of water sloshed out of the pool. However, for all critical damping factors, there was water lost into the ventilation ducts regardless of the direction of the seismic motion. The volume of the water lost in the ducts was conservatively calculated to be 59.5 ft3. Access to the SFP area as part of Phase 2 response could be challenged due to environmental conditions near the pool. Therefore, the required action is to establish ventilation in this area and establish any equipment local to the SFP required to accomplish the coping strategies (such as the primary SFP cooling strategy discussed below). If the air environment in the SFP area requires the building to be ventilated, doors will be opened to establish air movement and venting the SFP building. For accessibility, establishing the SFP vent and any other actions required inside the fuel handling building should be completed before boil off occurs.

Operating, pre-fuel transfer or post-fuel transfer Considering no reduction in SFP water inventory starting from nominal pool level, this results in a time when boil off decreases the water level to 10 feet above the SFP racks of approximately 85 hours9.837963e-4 days 0.0236 hours 1.405423e-4 weeks 3.23425e-5 months for an SSE seismic event with an initial bulk water temperature in the pool of 100°F. This value was calculated using the normal operating decay heat load.

Considering the maximum possible loss of water through the vents in SFP water inventory starting from nominal pool level, this results in a time when boil off occurs of approximately 18.69 hours7.986111e-4 days 0.0192 hours 1.140873e-4 weeks 2.62545e-5 months for an safe shutdown earthquake (SSE) seismic event and an initial bulk water temperature in the pool of 100°F. This value was calculated using the normal operating decay heat load. Time to boil the level to 10 ft. above the fuel racks (~735 ft.) for normal operating decay heat load is determined below. Note that the top of the fuel is at ~749 ft. and the boil off rate for normal decay heat load is 32.56 gpm as stated in Reference 18. A volume of level per inch of 104.38 ft3/in is from Reference 18.

Time to boil down to 10 ft. above (749-735=14 ft. = 168 in) fuel racks:

hours 84 85 69 18 15 67 min 60 hour6.944444e-4 days 0.0167 hours 9.920635e-5 weeks 2.283e-5 months 1

gal 56 32 min 1

ft 13368

.0 gal 1

in ft 38 104 in 168 3

3

u u

Fuel in Transfer or Full Core Offload For the maximum credible heat load and an initial water temperature in the pool of 140°F, the time when boil off decreases the water level to 10 feet above the SFP racks is approximately 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

Considering the maximum possible loss of water through the vents in SFP water inventory starting from nominal pool level, this results in a time when boil off occurs of approximately 4.58 hours6.712963e-4 days 0.0161 hours 9.589947e-5 weeks 2.2069e-5 months for a SSE seismic event and an initial bulk water temperature in the pool of 140°F. This value was calculated using the maximum operating decay heat load, as summarized in Reference 18. Time to boil the level to 10 ft. above the fuel racks (~735 ft.) for maximum credible heat load is determined below. Note that the top of the fuel is 4 Coping modifications consist of modifications installed to increase initial coping time, i.e., generators to preserve vital instruments or increase operating time on battery powered equipment.

E2-52 of 84 at ~749 ft. and the boil off rate for maximum credible heat load is 83.98 gpm as stated in Reference 18.

Time to boil down to 10 ft. above (749-735=14 ft. = 168 in) fuel racks:

hours 61 30 58

.4 03 26 min 60 hour6.944444e-4 days 0.0167 hours 9.920635e-5 weeks 2.283e-5 months 1

gal 98 83 min 1

ft 13368

.0 gal 1

in ft 38 104 in 168 3

3

u u

In order to keep the pool at a constant level of coolant (thus covering the top of the spent fuel), the LP FLEX pumps will be required to pressurize the ERCW headers to provide makeup to prevent a decrease in the level of the SFP.

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Procedures and guidance to support implementation of this strategy, including interfaces to EOIs, special event procedures, AOIs, and SOIs, will be developed in accordance with NEI 12-06, Revision 0, Section 11.4.

Further, the PWROG has developed generic guidance, and Watts Bars strategy aligns with the generic guidance and considers the NSSS specific guidance.

Identify Modifications 1). 8 Hour Battery Coping. (EDC/DCN 60976, DCN 60384 & PIC to DCN 54871).

2). Two independent SFP level instruments have been added to facilitate remote monitoring of SFP level in response to NRC Order EA 12-051.

(DCN 59683).

Key SFP Parameter The implementation of DCN 59683 aligned WBN with the requirements of NRC Order EA 12-051 and NEI 12-02.

These SFP Level instruments are powered from the 120v AC Vital Power System. The primary power supply to Spent Fuel Level Continuous Monitoring Loop 1 (0-LI-78-43) is from 120v AC Vital Power Board 2-III with its individual power supply battery backup (0-BAT-78-43). The primary power supply to Spent Fuel Level Continuous Monitoring Loop 2 (0-LI-78-42) is from 120v AC Vital Power Board 2-IV with its individual battery backup power supply (0-BAT-78-42). The 120v AC Vital Power Boards are powered by 120v AC Vital Inverters fed by its 125v DC Vital Battery Board. (Reference 39).

Notes:

E2-53 of 84 Maintain Spent Fuel Pool Cooling PWR Portable Equipment Phase 2:

Provide a general description of the coping strategies using on-site portable equipment including modifications that are proposed to maintain spent fuel pool cooling. Identify methods (makeup via portable injection source) and strategy (ies) utilized to achieve this coping time.

The transition to Phase 2 strategies will be as the inventory in the SFP slowly declines due to boiling. Initial SFP makeup should be from the Demineralized Water Head Tank until it is depleted. SFP cooling through makeup and/or spray will be provided by using LP FLEX pumps providing raw cooling or makeup water to the ERCW headers providing the capability for makeup from a FLEX connection and hose deployment directly into the pool or by spray from portable FLEX spray nozzles or by FLEX connection and hose deployment into existing SFP Demineralized Water System Makeup piping.

Through completion of proceduralized ERCW system alignment [0-FSI-5.05, ERCW Alignment for 5000 GPM Portable Diesel Pump (5PDP)] to focus raw cooling water availability and verification of 6.9KV FLEX DG loading necessary CCS and Spent Fuel Pool Cooling Pumps may be energized to restore SFP cooling capability.

Operating, Pre-fuel Transfer or Post-fuel Transfer Considering no reduction in SFP water inventory starting from nominal pool level, results in a time when boil off decreases the water level to 10 feet above the SFP racks of approximately 85 hours9.837963e-4 days 0.0236 hours 1.405423e-4 weeks 3.23425e-5 months for an SSE seismic event with an initial bulk water temperature in the pool of 100°F. This value was calculated using the normal operating decay heat load, shown in the Phase 1 section for Maintaining Spent Fuel Pool Cooling.

Fuel in Transfer or Full Core Offload For the maximum credible heat load and an initial water temperature in the pool of 140°F, the time when boil off decreases the water level to 10 feet above the SFP racks is approximately 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months , shown in the Phase 1 section for Maintain Spent Fuel Pool Cooling.

To provide an unlimited supply of water for SFP makeup during Phase 2, LP FLEX pumps will be used to pressurize the ERCW headers which can then be used for makeup to the SFP FLEX mitigation strategies.

For restoration of SFP cooling Watts Bar has the capability to repower one train of normal pool cooling equipment. This would include the use of LP FLEX pumps on site to provide flow to the CCS heat exchanger, ERCW System realignment per FSI-5.05 to focus raw cooling water availability and the pre-staged 6.9KV FLEX DGs to repower the necessary CCS and SFP cooling pumps.

The primary SFP makeup flow method is from the ERCW header connections on Elevation 757 from FLEX connections at the ERCW to CCS spool pieces (next to the CCS Surge Tanks) through a hose or hoses to the SFP. The secondary SFP makeup is a new FLEX connection added to the SFP Demineralized Water System (DWS) makeup line on elevation 737. Supply to this FLEX connection could come from an ERCW FLEX connection on AB elevation 737 (primary) or from an available clean water source via transfer pump, if available (secondary). This secondary makeup capability provides makeup control when the refueling floor is not accessible. Both FLEX connections can be accessed during both flood and non-flood conditions.

Watts Bar will provide portable (fire-fighting type) spray nozzle capability based on a flow of 500 gpm, which equals the FLEX requirement to provide 250 gpm of spray flow per unit to the spent fuel pool.

Details:

Provide a brief description of Procedures / Strategies /

Procedures and guidance to support deployment and implementation, including interfaces to EOIs, special event procedures, AOIs and SOIs, will be developed in accordance with NEI 12-06, Revision 0, Section 11.4.

E2-54 of 84 Maintain Spent Fuel Pool Cooling Guidelines Further, the PWROG has developed generic guidance, and Watts Bars strategy aligns with the generic guidance and considers the NSSS specific guidance.

Identify Modifications List modifications

1. FLEX connections have been provided at the ERCW headers in the IPS for the LP FLEX Pumps to pressurize the ERCW headers during non-flood and flood conditions. (DCN 60684).

2. FLEX connections have been provided at the ERCW headers in the 5th DG Building for the LP FLEX Pumps to pressurize the ERCW headers during non-flood or flood conditions. (DCN 60684).

3. FLEX connections have been provided on the ERCW headers in the AB elevation 737 for supplying raw water. (DCN 60684).

4. FLEX connections have been provided to the Tritiated Water Storage Tank (TWST), Primary Water Storage Tanks (PWSTs), and Demineralized Water Storage Tank for water transfer capability. (DCN 60684, DCN 60683, DCN 61784 & EDCR 60993).

5. The primary SFP FLEX connections with Storz fittings are located at the ERCW to CCS spool pieces (next to the CCS Surge Tanks) on Refuel floor elevation 757. These can supply direct makeup or spray if required. (DCN 60684).

6. The secondary SFP FLEX connection is located on Auxiliary Building elevation 737 (a tee, upstream isolation valve and FLEX connection are provided) on the Demineralized Water System piping leading to the SFP.

(DCN 60684).

7. 225kva DGs (480v FLEX DGs). (DCN 59675).

8. 3 MWe DGs (6.9KV FLEX DGs). (DCN 60853).

9. 8 Hour Battery Coping. (EDC/DCN 60976, DCN 60384 & PIC to DCN 54871).

10. Two independent SFP level instruments have been added to facilitate remote monitoring of SFP level in response to NRC Order EA 12-051.

(DCN 59683).

11. Miscellaneous - Installed storage boxes in the AB, IPS and 5th DG Building for hoses, fittings, tools required for implementation. Installed concrete pads and reinforced roads where required for FLEX equipment deployment. (DCN 62889).

Key SFP Parameter The implementation of this parameter will align with the requirements of NRC Order EA 12-051 and NEI 12-02.

These SFP Level instruments are powered from the 120v AC Vital Power System. The primary power supply to Spent Fuel Level Continuous Monitoring Loop 1 (0-LI-78-43) is from 120v AC Vital Power Board 2-III with its individual power supply battery backup (0-BAT-78-43). The primary power supply to Spent Fuel Level Continuous Monitoring Loop 2

E2-55 of 84 Maintain Spent Fuel Pool Cooling (0-LI-78-42) is from 120v AC Vital Power Board 2-IV with its individual battery backup power supply (0-BAT-78-42). The 120v AC Vital Power Boards are powered by 120v AC Vital Inverters fed by its 125v DC Vital Battery Board. (Reference 39).

Storage / Protection of Equipment:

Describe storage / protection plan or schedule to determine storage requirements Seismic Equipment required to implement this FLEX strategy is staged in the Auxiliary Building or the FESB, both are designed for seismic loading in excess of the minimum requirements of American Society of Civil Engineers (ASCE) 7-10. The SFP level instruments are mounted in the AB which is a protected structure. The design of the FESB provides a minimum HCLPF of 2x SSE. The 480v FLEX DGs are installed on the AB roof in a protected enclosure.

Flooding The 6.9KV FLEX DGs are pre-staged inside the FESB which is located above the PMF elevation. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The distribution system from the FESB to the EDG Building is protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is designed to withstand PMF waters, is appropriately protected or located within a class I structure.

The 480v FLEX DGs are pre-staged on the roof of the AB, which is sited in a suitable location that is above the PMF and as such is not susceptible to flooding from any source.

The SFP Level Instrumentation is located in the AB on the refuel floor elevation 757 with the level indication readout and backup power supply battery packs located in the shutdown board rooms on elevation 757. These are above PMF levels.

Severe Storms with High Winds Equipment required to implement this FLEX strategy is staged in the AB a class 1 structure or in the FESB, which is sited in a suitable location that is protected from NRC region 1 tornado, missiles, and velocities as defined in NRC Regulatory Guide 1.76 coupled with 360 mph wind speeds (Reference 5 Paragraph 2.3.1). The SFP level instruments are mounted in the AB which is a protected structure. The 480v FLEX DGs are installed on the AB roof in a protected enclosure.

Snow, Ice, and Extreme Cold The AB and the FESB have been evaluated for snow, ice and extreme cold temperature effects and heating is provided as required to assure no adverse effects on FLEX equipment or SFP level instrumentation. The FESB will have a standalone HVAC system. The 480v FLEX DGs are installed on the AB roof in a protected enclosure.

E2-56 of 84 Maintain Spent Fuel Pool Cooling High Temperatures The AB and FESB have been evaluated for high temperature effects and ventilation is provided as required to assure no adverse effects on FLEX equipment or SFP level instrumentation. The FESB has a standalone HVAC system. The 480v FLEX DGs are installed on the AB roof in a protected enclosure.

Deployment Conceptual Design (Attachment 3 contains Conceptual Sketches)

Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected The primary method is flow from the ERCW headers at two AB elevation 757 locations using adapters and hose connections.

This strategy can be implemented in flood and non-flood conditions.

The proposed hose routing for the primary method and the associated equipment can be found in, Figure A3-14 through A3-16. The system connection point can be found in, Figure A3-12.

Note that SFP spray would be routed in an identical manner; however, the end of the hose could have the spray nozzle installed.

ERCW connections can be found in Attachment 3, Figures A3-17 and A3-18.

The primary SFP FLEX connection modification will be an adapter where a hose connection can be installed at the ERCW supply valve to the CCS Surge Tank flood mode spool piece.

(DCN 60684).

ERCW Modifications The same modifications required to pressurize ERCW headers are described under Phase 2 Maintain Core Cooling and Heat Removal.

All FLEX equipment connection points will be designed to meet or exceed Watts Bar design basis SSE protection requirements.

The primary and secondary connections are in the Auxiliary Building, which is seismically qualified and missile protected.

The primary connection is above the PMF.

The secondary SFP connection will be to the DWS makeup line, on Elevation 737 of the AB. This strategy can be implemented in flood and non-flood conditions.

FLEX hose will be routed from this location, across the floor on Elevation 737, to the ERCW cleanout port FLEX connections.

The proposed hose routing for the secondary connection and the The secondary SFP FLEX connection modification includes:

x A tee added to the DWS makeup line to the SFP x

An isolation valve added to the main line upstream of the connection.

x An isolation valve added to the new branch.

x Storz cap/adapter added to the All FLEX equipment connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The connection point is in the Auxiliary Building, which is seismically qualified and missile protected. Hose routing to the primary connection will be performed before flood conditions make the area inaccessible.

E2-57 of 84 Maintain Spent Fuel Pool Cooling associated equipment can be found in Attachment 3, Figure A3-14 through A3-16. The system connection point can be found in, Figure A3-13.

ERCW connections can be found in Attachment 3, Figures A3-17 and A3-18.

new branch.

The modification that added FLEX connections to the ERCW cleanout ports described in the Reactor Core Cooling and Heat Removal section also applies to this case due to the location of the connection point. (DCN 60684).

Two independent SFP level instrument loops have been provided. One loop on the Unit 1 plant side on the Northwest corner of the SFP provides a SFP level indication mounted on the South wall of the A Train 6.9KV Shutdown Board. One loop on the Unit 2 plant side on the Southeast corner of the SFP provides a SFP level indication mounted on the South wall of the B Train 6.9KV Shutdown Board.

Two SFP level instruments have been added to facilitate remote monitoring of SFP level in response to NRC Order EA 12 -

051. (DCN 59683).

These SFP level instrument loop mounting are designed to meet or exceed Watts Bar design basis SSE protection requirements. All components are located in the AB, which is seismically qualified and missile protected.

These SFP Level instruments are powered from the 120v AC Vital Power System. The primary power supply to Spent Fuel Level Continuous Monitoring Loop 1 (0-LI-78-43) is from 120v AC Vital Power Board 2-III with its individual power supply battery backup (0-BAT-78-43). The primary power supply to Spent Fuel Level Continuous Monitoring Loop 2 (0-LI-78-42) is from 120v AC Vital Power Board 2-IV with its individual battery backup power supply (0-BAT-78-42). The 120v AC Vital Power Boards are powered by 120v AC Vital Inverters fed by its 125v DC Vital Battery Board. (Reference 39).

Notes:

1.

System modifications are described in the Modifications section above and are illustrated in.

2.

Figures A3-14 through A3-16 in Attachment 3 provides the hose routing for the SFP makeup strategies.

E2-58 of 84 Maintain Spent Fuel Pool Cooling PWR Portable Equipment Phase 3:

Provide a general description of the coping strategies using Phase 3 equipment including modifications that are proposed to maintain spent fuel pool cooling. Identify methods (makeup via portable injection source) and strategy (ies) utilized to achieve this coping time.

Details:

The strategies described for Phase 2 can continue as long as there is sufficient inventory available to feed the strategies. See SAFER/NSRC description and reference in the Phase 3 Details section for Maintaining Core Cooling and Heat Removal or the RCS Inventory Control sections.

Provide a brief description of Procedures / Strategies /

Guidelines Procedures and guidance to support deployment and implementation, including interfaces to EOIs, special event procedures, AOIs, and SOIs, have been developed in accordance with NEI 12-06, Revision 0, Section 11.4. Further, the PWROG has developed generic guidance, and Watts Bars strategy aligns with the generic guidance and considers the NSSS specific guidance.

TVA NPG has included in CECC EPIP - 3, Operations Duty Specialist Procedure For Alert, Site Area Emergency or General Emergency notification of the NSRC to arrange for delivery and deployment of off-site equipment and sufficient supplies of commodities. (Reference 40).

Identify Modifications N/A Key SFP Parameter The implementation of this parameter will align with the requirements of NRC Order EA 12-051 and NEI 12-02.

These SFP Level instruments are powered from the 120v AC Vital Power System. The primary power supply to Spent Fuel Level Continuous Monitoring Loop 1 (0-LI-78-43) is from 120v AC Vital Power Board 2-III with its individual power supply battery backup (0-BAT-78-43). The primary power supply to Spent Fuel Level Continuous Monitoring Loop 2 (0-LI-78-42) is from 120v AC Vital Power Board 2-IV with its individual battery backup power supply (0-BAT-78-42). The 120v AC Vital Power Boards are powered by 120v AC Vital Inverters fed by its 125v DC Vital Battery Board. (Reference 39).

Deployment Conceptual Design (Attachment 3 contains Conceptual Sketches)

Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected The description for the mobile water purification system will be the same as was mentioned for the other functions.

The description for the mobile water purification system will be the same as was mentioned for the other functions.

The primary and secondary methods would remain the same.

The difference would be the drivers which would be the NSRC delivered pumps, if they were required.

The following FLEX connections provide potential connection points or adapters for Phase 3 portable pumps (suction source and discharge options) if they are required to be deployed:

All FLEX connection points are designed to meet or exceed Watts Bar design basis SSE protection requirements.

The connection points in the AB, IPS or 5th DG Building are

E2-59 of 84 Maintain Spent Fuel Pool Cooling The primary method is flow from the ERCW headers at two AB elevation 757 locations using adapters and hose connections.

This strategy can be implemented in flood and non-flood conditions.

The proposed hose routing for the primary method and the associated equipment can be found in, Figure A3-14 through A3-16. The system connection point can be found in, Figure A3-12.

Note that SFP spray would be routed in an identical manner; however, the end of the hose could have the spray nozzle installed.

ERCW connections can be found in Attachment 3, Figures A3-17 and A3-18.

The secondary SFP connection will be to the DWS makeup line, on Elevation 737 of the AB. This strategy can be implemented in flood and non-flood conditions.

FLEX hose will be routed from this location, across the floor on Elevation 737, to the ERCW cleanout port FLEX connections.

The proposed hose routing for the secondary connection and the associated equipment can be found in Attachment 3, Figure A3-14 through A3-16. The system connection point can be found in, Figure A3-13.

ERCW connections can be found in Attachment 3, Figures A3-17 and A3-18.

1. FLEX connections have been provided at the ERCW headers in the Intake Pumping Station (IPS) for the LP FLEX Pumps to pressurize the ERCW headers during non-flood and flood conditions. (DCN 60684).

2. FLEX connections have been provided at the ERCW headers in the 5th DG Building for the LP FLEX Pumps to pressurize the ERCW headers during non-flood or flood conditions.

(DCN 60684).

3. FLEX connections have been provided on the ERCW headers in the AB elevation 737 for supplying raw water. (DCN 60684).

4. FLEX connections have been provided to the Tritiated Water Storage Tank (TWST), Primary Water Storage Tanks (PWSTs),

and Demineralized Water Storage Tank (DWST) for potential water transfer capability. (DCN 60684, DCN 60683, DCN 61784 & EDCR 60993).

5. The primary SFP FLEX connections with Storz fittings are located at the ERCW to CCS spool pieces (next to the CCS Surge Tanks) on Refuel floor elevation 757. These can supply direct makeup or spray if required. (DCN 60684).

6. The secondary SFP FLEX connection is located on AB elevation 737 (a tee, upstream isolation valve and FLEX connection are provided) on the Demineralized Water System piping leading to the SFP.

(DCN 60684).

seismically qualified and missile protected.

Notes:

1. System modifications are described in the Modifications section above and are illustrated in Attachment

2. Figures A3-14 through A3-16 in Attachment 3 provides the hose routing for the SFP makeup strategies.

E2-60 of 84 Safety Functions Support Determine Baseline coping capability with installed coping5 modifications not including FLEX modifications.

PWR Installed Equipment Phase 1 Provide a general description of the coping strategies using installed equipment including station modifications that are proposed to maintain and/or support safety functions. Identify methods and strategy (ies) utilized to achieve coping times.

Analysis using conservative heat loads in the Control and Auxiliary Buildings has shown that installed equipment credited for mitigation response will remain available. In addition, accessibility of these areas for required actions is acceptable. (Reference 14).

Habitability and Operations Operating Conditions Following a BDBEE and subsequent ELAP event, plant heating, ventilation and air conditioning (HVAC) in occupied areas and areas containing permanent plant and FLEX mitigation strategy equipment will be lost.

Per NEI 12-06, FLEX mitigation strategies must be capable of execution under the adverse conditions (unavailability of normal plant lighting, ventilation, etc.) expected following a BDBEE resulting in an ELAP/LUHS. The primary concern with regard to ventilation is the heat buildup which occurs with the loss of forced ventilation in areas that continue to have heat loads. A loss of ventilation analyses was performed to quantify the maximum steady state temperatures expected in specific areas related to FLEX mitigation strategy implementation to ensure the environmental conditions remain acceptable for personnel habitability and within equipment qualification limits. (Reference 14).

The areas identified for all phases of execution of the FLEX mitigation strategy activities are the MCR, Shutdown Board Rooms, AB, TDAFWP rooms, EDG Building, 5th DG Building, FESB and IPS. These areas have been evaluated to determine the temperature profiles following an ELAP/LUHS event. The calculation has concluded that temperatures remain within acceptable limits based on conservative input heat load assumptions for all areas with no actions being taken to reduce heat load or to establish either active or passive ventilation (e.g., portable fans, open doors, etc.). In the case of the TDAFW Pump rooms the pump room doors will be opened and left open to facilitate natural circulation and ensure that the temperatures remain within the acceptable range for equipment and personnel. The temperatures expected in the MSVVs for local operation of SG PORVs, if required, are similar to conditions experienced during normal station operations, testing, and maintenance. Therefore, actions performed for FLEX activities will be essentially the same as those evaluated for the current site procedure ECA-0.0, Loss of All AC Power or B.5.b strategies which also address potential local operation of the TDAFWP, AFW LCVs and/or SG PORVs.

Off-gassing of hydrogen from batteries is only a concern when the batteries are charging. Vital Battery Room doors will be blocked open to facilitate natural ventilation.

Lighting In an ELAP event initial lighting for the MCR and Shutdown Board Room areas is provided by the plant designed 125v DC powered emergency lighting system, designated by the LD prefix. This system now utilizes LED light bulbs which have enhanced 125v Vital Battery coping capability. (Reference 30). The Auxiliary Control Room (ACR), access and egress routes and areas that must be attended for safe shutdown Coping modifications consist of modifications installed to increase initial coping time, i.e., generators to preserve vital instruments or increase operating time on battery powered equipment.

E2-61 of 84 operations are provided with 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months emergency battery lighting (EBL) units. The EBL units that support safe shutdown and emergency access and egress are routinely referred to as Appendix R battery packs. These Appendix R EBLs are upgrading to LED bulbs which provide extended battery pack life. Tasks required to implement FLEX mitigation strategies including traveling to/from the various areas necessary to implement the FLEX strategies, making performing instrumentation monitoring, and component manipulations are similar to tasks previously walked down for ECA-0.0 Loss of Shutdown Power, B.5.b and Appendix R Safe Shutdown operations.

These emergency lights are periodically tested under the plants preventative maintenance program to insure the battery pack will provide a minimum of eight (8) hours of lighting with no external AC power sources.

Communications Watts Bar Unit 1 & 2 communications systems and equipment are designed and installed to ensure reliability of onsite and offsite communications in the event of a design basis or BDBEE. WBNs ELAP mitigation capability benefits from a previously planned upgrade of WBNs radio communication system. DCN 60384 has converted the analog Nextel Radio System to a trunked VHF and UHF digital system with new multi-ban handheld radios. The new radio system hardware (cabinets, repeaters, hand held radios, etc.) are provided by the Harris Corporation.

Three regulatory rules from the Code of Federal Regulations (CFR) that are satisfied by the system upgrade are:

x Emergency Preparedness (EP): both an on site and offsite communication system exists with a normal and backup power supply.

x Security: constant communication between the Central Alarm Station (CAS) and any officer in the field at all times.

x 10CFR50 Appendix R for fire protection: communication method is available to respond to certain Design Basis fires with in the plant.

Six new cabinets containing communication equipment have been installed inside the AB, a class I structure protected against environmental events such as seismic, tornado, high winds, extreme cold or high temperatures and they and their power supplies are located above site probable maximum flood elevation.

Five cabinets are installed in the 480v shutdown board room 2A on AB elevation 772. These cabinets are normally powered from safety related normal and backup 120V AC feeds. The normal feeds (which would not be available in Phase I of an ELAP event) are from 480v Reactor MOV Board 2A1-A or 2B1-B (transformed 480v AC to 120v AC) and the back up feed power supply capability (which would be powering the Harris Radio system during Phase I) is provided through either 120v AC Vital Instrument Power Board 2-III or 2-IV. The 120V AC Vital Instrument Power Boards are fed from their designated vital inverter powered respectively by 125v Vital Battery III or IV.

The sixth cabinet is installed in the 480v Shutdown Transformer Room 2B on AB elevation 772. The sixth cabinet and radio is separated from the other five cabinets to address Appendix R requirements and is powered from a safety related 120V AC Instrument Power Distribution Panel 2B (2-BD-237-B). This cabinet would not be available during Phase I of an ELAP event.

WBN maintains a sound powered phone system. There are four plant sound powered phone sub-divisions:

Shutdown Sound Powered System, Plant Operations Sound Powered System, Health Physics Sound Powered System and Diesel Generator Sound Powered System. The sound-powered telephone system is a communication system which utilizes telephone instruments in which the transmitters and receivers are passive transducers; external power is not required since operating power is obtained from the speech input

E2-62 of 84 only. These systems provide two communication functions, the first of which is to furnish voice communications when conventional voice circuits are inoperative, and the second of which is to furnish voice communications for plant operation or maintenance purposes. The Shutdown Sound Powered System is the only sound power communication system designed expressly for supporting the emergency shutdown of the reactors, if required. This system consists of fixed and portable sound powered telephones and jack circuits for two separate, redundant circuits called the primary system and alternate system. Although this system maybe used as deemed necessary, its intended use is not for normal plant operations. It provides a backup communication vehicle for operations in the Auxiliary Control Room (ACR), 6900v and 480v Shutdown Board Rooms, AB elevation 692 near TDAFWP rooms, EDG Building and North and South MSVVs elevation 729 near SG PORVs during an emergency. It is not accessible in the MCR. Instructions are provided in plant System Operating Instruction (SOI) and an AOI-27 cabinet outside of the ACR contains sound powered communication headsets and support equipment. This system is active in the plants preventative maintenance program.

TVA purchased 17 IsatPhone PRO global handheld satellite phones for Watts Bar. The SatPhone Battery Life is Talk Time: Up to 8 Hours; Standby Time: Up to 100 Hours. These phones are deployed in the MCR at the Shift Manager - Senior Reactor Operators (SRO) desk, in the TSC, Central Alarm Station (CAS),

Environmental Monitoring Vans, with individuals on-site, and in the Emergency Planning (EP) office area.

In addition spare batteries are kept fully charged that are available at the TSC, CAS, and EP offices. This gives the individual phones 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months of talk time before recharging is needed. The phone in the vans is charged using the standard 12V adapter and will remain available throughout the duration of the event.

A fixed docking station, IsatDock PRO allows the IsatPhone Pro handset to be interfaced with a PBX system presenting standard ring, busy and dial tones like a standard phone network. This docking station is located in the NODE 2, Telecommunications Building. The phone is located in the MCR, TSC, and OSC.

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Confirm that procedure/guidance exists or will be developed to support implementation.

Procedures and guidance to support deployment and implementation, including interfaces to EOIs, special event procedures, AOIs, and SOIs, will be developed in accordance with NEI 12-06, Revision 0, Section 11.4.

Further, the PWROG has developed generic guidance, and Watts Bar's strategy aligns with the generic guidance and considers the NSSS specific guidance.

Identify Modifications List modifications and describe how they support coping time.

1. 8 Hour Battery Coping. (EDC/DCN 60976, DCN 60384 & PIC to DCN 54871). The replacement of incandescent lamps with LED lamps in emergency lighting for the Main Control Room and Shutdown Board Rooms and Appendix R Light Packs provides for additional margin on the 125v DC Vital Battery Systems.

Key Parameters List instrumentation credited for this coping evaluation phase.

x 125v DC Vital Battery Bus Voltage (for 125v DC Vital Batteries I, II, III

& IV).

Watts Bar relies on existing installed 125v DC Vital Batteries to power key instrumentation and emergency lighting. A battery coping calculation determined that the battery coping time is 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months . (Reference 30).

Notes:

E2-63 of 84 Safety Functions Support PWR Portable Equipment Phase 2 Provide a general description of the coping strategies using on-site portable equipment including station modifications that are proposed to maintain and/or support safety functions. Identify methods and strategy (ies) utilized to achieve coping times.

Analysis using conservative heat loads in the Control and Auxiliary Buildings has shown that installed equipment credited for mitigation response will remain available. In addition, accessibility of these areas for required actions is acceptable. (Reference 14).

The on-site 480v FLEX DGs are pre-staged to provide power to the 125v DC Vital Batteries and through the Vital Inverters the 120v AC Vital Instrument Power System. These generators are pre-staged on the Auxiliary Building roof and will be protected from external hazards with an initial supply of fuel for 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months of operation. Once the fuel and control cable FLEX connections are complete to ensure continuous fuel supply to the 480v FLEX DGs there is not an issue with 125v Vital DC coping capability.

Additionally, the onsite 6.9KV FLEX DGs are pre-staged in the FESB to provide power to the existing 6.9KV Shutdown Power distribution system and via the 480v Shutdown Transformers the 480v Shutdown Power distribution system. The 6.9KV FLEX DGs also provide an alternative power source capability for the loads supplied by the on-site 480v FLEX DGs. The 6.9KV FLEX DGs electrical distribution network is protected from the external hazards discussed in this document.

Habitability and Operations Operating Conditions Following a BDBEE and subsequent ELAP event, plant heating, ventilation and air conditioning (HVAC) in occupied areas and areas containing permanent plant and FLEX mitigation strategy equipment will be lost.

Per NEI 12-06, FLEX mitigation strategies must be capable of execution under the adverse conditions (unavailability of normal plant lighting, ventilation, etc.) expected following a BDBEE resulting in an ELAP/LUHS. The primary concern with regard to ventilation is the heat buildup which occurs with the loss of forced ventilation in areas that continue to have heat loads. A loss of ventilation analyses was performed to quantify the maximum steady state temperatures expected in specific areas related to FLEX mitigation strategy implementation to ensure the environmental conditions remain acceptable for personnel habitability and within equipment qualification limits. (Reference 14).

The areas identified for all phases of execution of the FLEX mitigation strategy activities are the MCR, Shutdown Board Rooms, AB, TDAFWP rooms, EDG Building, 5th DG Building, FESB and IPS. These areas have been evaluated to determine the temperature profiles following an ELAP/LUHS event. The calculation has concluded that temperatures remain within acceptable limits based on conservative input heat load assumptions for all areas with no actions being taken to reduce heat load or to establish either active or passive ventilation (e.g., portable fans, open doors, etc.) In the case of the TDAFW Pump rooms, Safety Injection Pumps rooms, and the PD Pumps rooms (location of the HP FLEX Pumps) the pump room doors will be opened and left open to facilitate natural circulation and ensure that the temperatures remain within the acceptable range for equipment and personnel. These doors will remain open to support pump operation.

The temperatures expected in the MSVVs for local operation of SG PORVs, if required, are similar to conditions experienced during normal station operations, testing, and maintenance. Actions performed within the plant for FLEX activities will be essentially the same as those performed for the current site procedure ECA-0.0, Loss of All AC Power or potentially for B.5.b or Appendix R Safe Shutdown strategies which also address potential local operation of the TDAFWP, AFW LCVs and SG PORVs.

An additional ventilation concern applicable to Phase 2 is when the 480v FLEX DGs repower the 125v Vital Battery Chargers. Off-gassing of hydrogen from batteries is only a concern when the batteries are charging.

E2-64 of 84 Safety Functions Support PWR Portable Equipment Phase 2 Vital Battery room doors will be blocked open to facilitate natural ventilation. Once the 6900v FLEX DGs restore power to the 6.9KV and 480v shutdown power distribution systems the capability of returning the battery room ventilation fans to service exists.

Lighting In an ELAP event initial lighting for the MCR and Shutdown Board Room areas is provided by the plant designed 125v DC powered emergency lighting system, designated by the LD prefix. This system utilizes LED light bulbs. The Auxiliary Control Room (ACR), access and egress routes and areas that must be attended for safe shutdown operations are provided with 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months emergency battery lighting (EBL) units. The EBL units that support safe shutdown and emergency access and egress are routinely referred to as Appendix R battery packs. These Appendix R EBLs are upgrading to LED bulbs which provide extended battery life. Traveling to and from the various areas necessary to implement the FLEX mitigation strategies, making required mechanical connections, operating electrical disconnects and breakers, monitoring instrumentation and component manipulations are similar to tasks previously walked down for B.5.b and Appendix R Safe Shutdown operations.

Battery Powered (Appendix R) emergency lights were determined to provide adequate lighting for all interior travel pathways needed to access the connection points. These emergency lights are designed and periodically tested under the plants preventative maintenance program to insure the battery pack will provide a minimum of eight (8) hours of lighting with no external AC power sources.

Once the 6900v FLEX DGs repower the 6.9KV Shutdown Boards and the 480v shutdown powered distribution system the Standby Lighting system, designated by the LS prefix, could be directed to be repowered from the Reactor MOV Boards supplying lighting and placing the 125v DC powered emergency lighting system (LD system) back in a standby mode. 6900v FLEX DG loading should be evaluated prior to reenergizing the LS lighting system.

There are no emergency lighting fixtures in the yard outside of the protected area to provide necessary lighting in those areas where portable FLEX equipment is to be deployed. Therefore, the diesel powered FLEX pumps and generators are outfitted with light plants that are powered from their respective diesels to support connection and operation. In addition to the lights installed on the portable diesel powered FLEX equipment, portable diesel generator powered light stanchions, battery powered light packs and small generators to provide power and battery charging capability are available to be deployed from the FESB to support fading light or night time operations.

The FESB will also include a stock of flashlights and head lights to further assist the staff responding to an ELAP.

Communications Watts Bar Unit 1 & 2 communications systems and equipment are designed and installed to ensure reliability of onsite and offsite communications in the event of a design basis or BDBEE. WBNs ELAP mitigation capability benefits from a previously planned upgrade of WBNs radio communication system. DCN 60384 has converted the analog Nextel Radio System to a trunked VHF and UHF digital system with new multi-ban handheld radios. The new radio system hardware (cabinets, repeaters, hand held radios, etc.) are provided by the Harris Corporation.

Three regulatory rules from the Code of Federal Regulations (CFR) that are satisfied by the system upgrade are:

E2-65 of 84 Safety Functions Support PWR Portable Equipment Phase 2 x

Emergency Preparedness (EP): both an on site and offsite communication system exists with a normal and backup power supply.

x Security: constant communication between the Central Alarm Station (CAS) and any officer in the field at all times.

x 10CFR50 Appendix R for fire protection: communication method is available to respond to certain Design Basis fires with in the plant.

Six new cabinets containing communication equipment have been installed inside the AB, a class I structure protected against environmental events such as seismic, tornado, high winds, extreme cold or high temperatures and they and their power supplies are located above site probable maximum flood elevation.

Five cabinets are installed in the 480v Shutdown Board Room 2A on AB elevation 772. These cabinets are normally powered from safety related normal and backup 120V AC feeds. The normal feeds are from 480v Reactor MOV Board 2A1-A or 2B1-B (transformed 480v AC to 120v AC) and the back up feed power supply capability is provided through either 120v AC Vital Instrument Power Board 2-III or 2-IV. The 120V AC Vital Instrument Power Boards are fed from their designated vital inverter powered respectively by 125v Vital Battery III or IV. In an ELAP event the ultimate source for normal power once placed in service would be the 6900v FLEX DGs repowering the 6.9KV Shutdown and 480v AC Shutdown Power distribution systems and for the backup power feeds the 480v FLEX DGs repowering the 125v DC Vital Battery chargers ensuring continuous 125v DC coping capability and power to the 120c AC Vital Inverters.

The sixth cabinet is installed in the 480v Shutdown Transformer Room 2B on AB elevation 772. The sixth cabinet and radio is separated from the other five cabinets to address Appendix R requirements and is powered from a safety related 120V AC Instrument Power Distribution Panel 2B (2-BD-237-B).

WBN maintains a sound powered phone system. There are four plant sound powered phone sub-divisions:

Shutdown Sound Powered System, Plant Operations Sound Powered System, Health Physics Sound Powered System and Diesel Generator Sound Powered System. The sound-powered telephone system is a communication system which utilizes telephone instruments in which the transmitters and receivers are passive transducers; external power is not required since operating power is obtained from the speech input only. These systems provide two communication functions, the first of which is to furnish voice communications when conventional voice circuits are inoperative, and the second of which is to furnish voice communications for plant operation or maintenance purposes. The Shutdown Sound Powered System is the only sound power communication system designed expressly for supporting the emergency shutdown of the reactors, if required. This system consists of fixed and portable sound powered telephones and jack circuits for two separate, redundant circuits called the primary system and alternate system. Although this system maybe used as deemed necessary, its intended use is not for normal plant operations. It provides a backup communication vehicle for operations in the Auxiliary Control Room (ACR), 6900v and 480v Shutdown Board Rooms, AB elevation 692 near TDAFWP rooms and North and South MSVVs elevation 729 and EDG Building near SG PORVs during an emergency. It is not accessible in the MCR. Instructions are provided in plant System Operating Instruction (SOI) and an AOI-27 cabinet outside of the ACR contains sound powered communication headsets and support equipment. This system is active in the plants preventative maintenance program.

TVA purchased 17 IsatPhone PRO global handheld satellite phones for Watts Bar. The SatPhone Battery Life is Talk time: Up to 8 Hours; Standby Time: Up to 100 Hours. These phones are deployed in the MCR at the Shift Manager - Senior Reactor Operators (SRO) desk, in the TSC, Central Alarm Station (CAS),

Environmental Monitoring Vans, with individuals on-site, and in the Emergency Planning (EP) office area.

E2-66 of 84 Safety Functions Support PWR Portable Equipment Phase 2 In addition spare batteries are kept fully charged that are available at the TSC, CAS, and EP offices. This gives the individual phones 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months of talk time before recharging is needed. The phone in the vans is charged using the standard 12V adapter and will remain available throughout the duration of the event.

A fixed docking station, IsatDock PRO allows the IsatPhone Pro handset to be interfaced with a PBX system presenting standard ring, busy and dial tones like a standard phone network. This docking station is located in the NODE 2, Telecommunications Building. The phone is located in the MCR, TSC, and OSC.

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Confirm that procedure/guidance exists or will be developed to support implementation with a description of the procedure / strategy / guideline.

Procedures and guidance to support deployment and implementation, including interfaces to EOIs, special event procedures, AOIs, and SOIs, have been developed in accordance with NEI 12-06, Revision 0, and Section 11.4. Further, the PWROG has developed generic guidance, and Watts Bar's strategy aligns with the generic guidance and considers the NSSS specific guidance.

Identify Modifications For the 480v FLEX DGs, two fused distribution panels will be used to provide power to the supplied loads. Each 480v FLEX DG fuse panel provides connections to two Vital Battery chargers. Each fuse distribution panel provides connection capability to the 480v AC Shutdown Power distribution systems 480V Reactor MOV Boards with the ability to close Cold Leg Accumulator Isolation Valves during cooldown, if required. In an ELAP event A 480v FLEX DG would supply power to 125v DC Vital Battery Chargers I & III and B 480v FLEX DG would supply power to 125v DC Vital Battery Chargers II & IV. The A 480v FLEX DG schematic is shown on Attachment 3, Figure A3-22. B 480v FLEX DG schematic (not shown) is similar.

Fuel for the 480v FLEX DGs will be provided by the installed EDG 7-day tanks. Fuel lines will be installed between the 7-day fuel tanks mounted under the EDG building and AB roof to provide fuel to the 480v FLEX DGs with a fuel transfer pump. The 480v FLEX DGs fuel and control power FLEX connections must be completed and protected within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months to ensure unlimited coping capability provided by the 480v FLEX DGs. (DCN 59675).

To connect the existing 6.9KV Shutdown Power System to the 6.9KV FLEX DGs for FLEX implementation and operation, the connection to the existing safety-related DG circuit is opened and the circuits to the 6.9KV FLEX DGs are closed by operating the existing interlocked (Kirk-Key) transfer switches 1A-A, 1B-B, 2A-A, or 2B-B.

The permanently installed electrical connection points for the 6.9KV FLEX DGs are from the DGs integral output connection panel through conduits within the FESB to underground conduits located on the outside of the FESB south wall. One 6.9KV FLEX DG is assigned to power Train A on both units and the second 6.9KV FLEX DG is assigned to power Train B of both units. A 6.9KV FLEX DG power supply routing to 1A-A 6.9KV Shutdown Board and distribution is shown on Attachment 3, Figure A3-21.

E2-67 of 84 Safety Functions Support PWR Portable Equipment Phase 2 A 6.9KV FLX DG would supply both 1A-A and 2A-A 6.9KV Shutdown Boards through their respective Kirk-Key disconnect switches and shutdown board emergency feeder breaker. B 6.9KV FLEX DG (not shown) would supply 1B-B and 2B-B 6.9KV Shutdown Boards.

The conduits meet seismic Class I requirements for safety related and quality-related structures. Actual mechanical and electrical connections to the presently installed safety related DG equipment shall meet safety related requirements at the interfaces.

Refueling of the 6.9KV FLEX DGs is accomplished by separate diesel fuel transfer pumps taking suction from two separate designated EDG 7-day fuel oil tanks and transferring and maintaining fuel to the 6.9KV FLEX DGs fuel oil day tanks. (DCN 60853).

Key Parameters List instrumentation credited or recovered for this coping evaluation.

x 125v DC Vital Batteries Bus Voltage For the instrument listed above the normal power source and the long-term power source are the 125v DC Vital Battery.

Storage / Protection of Equipment Describe storage / protection plan or schedule to determine storage requirements Seismic Equipment for this function will either be stored or pre-staged in the FESB, in the AB, IPS or 5th DG Building. The protection of FLEX equipment for this hazard is addressed for each of these locations in the Reactor Core Cooling and Heat Removal and Maintain RCS Inventory Control sections.

Flooding Equipment for this function will either be stored or pre-staged in the FESB, in the AB, IP or 5th DG Building. The protection of FLEX equipment for this hazard is addressed for each of these locations in the Reactor Core Cooling and Heat Removal and Maintain RCS Inventory Control sections.

Severe Storms with High Winds Equipment for this function will either be stored or pre-staged in the FESB, in the AB, IPS or 5th DG Building. The protection of FLEX equipment for this hazard is addressed for each of these locations in the Reactor Core Cooling and Heat Removal and Maintain RCS Inventory Control sections.

Snow, Ice, and Extreme Cold Equipment for this function will either be stored or pre-staged in the FESB, in the AB, IPS or 5th dg Building. The protection of FLEX equipment for this hazard is addressed for each of these locations in the Reactor Core Cooling and Heat Removal and Maintain RCS Inventory Control sections.

High Temperatures Equipment for this function will either be stored or pre-staged in the FESB, in the AB, IPS or 5th DG Building. The protection of FLEX equipment for this hazard is addressed for each of these locations in the Reactor Core Cooling and Heat Removal and Maintain RCS Inventory Control sections.

E2-68 of 84 Safety Functions Support PWR Portable Equipment Phase 2 Deployment Conceptual Design (Attachment 3 contains Conceptual Sketches)

Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected The strategy for this function is described above in the Identify Modifications section.

1. 225kva DGs (480v FLEX DGs). (DCN 59675)

2. 3 MWe DGs (6.9KV FLEX DGs) (DCN 60853)

3. 8 Hour Battery Coping.

(EDC/DCN 60976, DCN 60384 & PIC to DCN 54871)

Note: The Harris Radio system modification is included in DCN 60384.

The 6.9KV FLEX DGs are pre-staged inside the FESB above the PMF elevation. The FESB is a formidable structure designed and built to withstand 2X SSE HCLPF and 360 MPH winds. The distribution system from the FESB to the EDG Building is protected and from the kirk-key switches located in the EDG through the 6.9KV and 480v safety class electrical distribution system is appropriately protected or located within a class I structure.

The 480v FLEX DGs are pre-staged on the roof of the AB. A protection structure has been built around the DGs, which is designed to the same Seismic Category I requirements as the AB. Seismic input for the design corresponds to the appropriate seismic accelerations at the roof of the AB.

This design provides a seismic protection of 2xSSE HCLPF.

The electrical distribution systems are located in the EDG building and/or the AB which are protected structures.

Notes: None.

E2-69 of 84 Safety Functions Support PWR Portable Equipment Phase 3 Provide a general description of the coping strategies using Phase 3 equipment including modifications that are proposed to maintain and/or support safety functions. Identify methods and strategy (ies) utilized to achieve coping times.

See SAFER/NSRC description and reference in the Phase 3 Details section for Maintaining Core Cooling and Heat Removal or the RCS Inventory Control sections. A backup or alternate set of Phase 2 equipment will be provided by the NSRC or from offsite TVA sources, as needed.

Details:

Provide a brief description of Procedures / Strategies /

Guidelines Procedures and guidance to support deployment and implementation, including interfaces to EOIs, special event procedures, AOIs, and SOIs, will be developed in accordance with NEI 12-06, Revision 0, Section 11.4.

Further, the PWROG has developed generic guidance, and Watts Bars strategy aligns with the generic guidance and considers the NSSS specific guidance.

TVA NPG has included in CECC EPIP - 3, Operations Duty Specialist Procedure For Alert, Site Area Emergency or General Emergency notification of the NSRC to arrange for delivery and deployment of off-site equipment and sufficient supplies of commodities. (Reference 40)

Identify Modifications N/A Key Parameters No additional instrumentation is required to support the Phase 3 safety function support.

Deployment Conceptual Design (Attachment 3 contains Conceptual Sketches)

Strategy Modifications Protection of connections Identify Strategy including how the equipment will be deployed to the point of use.

Identify Modifications Identify how the connection is protected A backup to or alternate set of Phase 2 equipment will be provided by the NSRC or offsite TVA sources, as needed.

Each of the Phase 3 strategies utilize common connections or adapters as described for the Phase 2 connections to prevent any compatibility issues with the offsite equipment.

There are no unique phase 3 connection points for this strategy.

All phase 3 equipment will be provided by offsite resources.

Notes: None

E2-70 of 84 PWR Portable Equipment Phase 2 Use and (potential/flexibility) diverse uses Performance Criteria1 Maintenance List portable/pre-staged equipment Core Containment SFP Instrumentation Accessibility Maintenance / PM requirements Two Pre-Staged Medium Voltage Diesel Generators (6900v FLEX DGs) -

Repowers 6.9 KV Shutdown Boards.

X X

X 6900v AC 3 MWe Follows EPRI template requirements.

Two Pre-Staged Low Voltage Diesel Generators (480v FLEX DGs) - Powers the 125v DC Vital Battery Chargers.

X X

X 480v AC 225 kva Follows EPRI template requirements Three (Dominator) Low Pressure (LP) FLEX Pumps (Pressurizes ERCW Headers)

X X

X 5000 gpm 150 PSIG [350 ft. Total Dynamic Head (TDH)]

Diesel Driven Follows EPRI template requirements Three (Triton) LP FLEX Pump Systems - each consist of 2 floating hydraulically driven booster pumps supplying positive suction to the Low Pressure FLEX Pumps (Dominators).

X X

X 5000 gpm 50 ft. lift Diesel Powered Hydraulically Driven Floating Booster Pumps Follows EPRI template requirements Two Intermediate Pressure FLEX Pumps (Core Cooling Makeup Pumps - Non-Flood Events)

X X

150 gpm 350 PSIG (823 ft. TDH)

Diesel Driven Follows EPRI template requirements 1 Performance criteria of FLEX equipment is conservative and was determined during conceptual design as a basis for the selection of required FLEX equipment.

(Reference 20).

E2-71 of 84 PWR Portable Equipment Phase 2 Use and (potential/flexibility) diverse uses Performance Criteria1 Maintenance List portable/pre-staged equipment Core Containment SFP Instrumentation Accessibility Maintenance / PM requirements Two Pre-Staged Intermediate Pressure FLEX Pumps (Core Cooling Makeup Pumps - Flood Event)

X 150 gpm 350 PSIG (823 ft. TDH) 480v AC Motor Driven Follows EPRI template requirements Two Pre-Staged Mode 5 & 6 FLEX Pumps (RCS Core Cooling and Makeup Pumps

- Non-Flood or Flood Event)

X 150 gpm 350 PSIG (823 ft. TDH) 480v AC Motor Driven Follows EPRI template requirements Three Pre-Staged High Pressure FLEX Pumps (RCS Inventory Control -Non-Flood or Flood Event)

X 40 gpm 600 PSIG (1384 ft. TDH) 480v AC Motor Driven Follows EPRI template requirements Two Water Transfer Pumps X

X 500 gpm 160 PSIG (374 ft. TDH)

Diesel Driven Follows EPRI template requirements Two SFP Spray Nozzles X

250 gpm per nozzle Follows EPRI template requirements Two Heavy Duty 4X4 Vehicles capable of debris removal, deployment of FLEX equipment, personnel transport and refueling diesel powered FLEX equipment.

X X

X Capable of on-site debris removal, deployment of trailer mounted FLEX equipment, transport of personnel, refueling of diesel powered FLEX equipment. Equal to or greater tow capacity of 14,000 Gross Vehicle Follows EPRI template requirements

E2-72 of 84 PWR Portable Equipment Phase 2 Use and (potential/flexibility) diverse uses Performance Criteria1 Maintenance List portable/pre-staged equipment Core Containment SFP Instrumentation Accessibility Maintenance / PM requirements Weight (GVW). Each truck has a bed mounted 500 gallon fuel tank and fuel transfer pump.

Fuel Transfer Equipment x

One Diesel Powered Fuel Transfer Pump x

One Portable Electric Powered Fuel Transfer Pump X

X X

Provides refuel capability by fuel transfer from the EDG 7-day tanks or surviving fuel oil storage tanks to the truck mounted 500 gallon fuel tanks or transfer from tank to tank.

Follows EPRI template requirements Debris Clearing Equipment One Compact Track Loader.

The previously identified tow vehicles (4X4 trucks) equipped for debris removal duty, if required.

X X

Capable of clearing trees, light poles, building, fencing or wire, construction materials and/or miscellaneous debris.

One 4X4 truck is equipped with a heavy duty front mounted 16.5 ton winch and a second truck is mounted with a debris or snow removal plow.

Follows EPRI template requirements

E2-73 of 84 PWR Portable Equipment Phase 3 Use and (potential/flexibility) diverse uses Performance Criteria 1 Phase 3 NSRC/SAFER Equipment or Other available offsite equipment.

List portable/pre-staged equipment Core Containment SFP Instrumentation Accessibility Medium Voltage Diesel Generator Backup X

X X

6900v AC capable of powering minimum mitigation strategy equipment Use of TVA owned 2.2 MW Diesel Generator(s) and 480v to 6.9KV transformer(s).

Low Voltage Diesel Generator Backup X

X X

480v AC 225 kva Low Voltage Generator Low Pressure FLEX Pumps (Dominator)

(Pressurizes ERCW Headers)

X X

X 5000 gpm 150 PSIG (350 ft. TDH)

Diesel Driven Low Pressure High Flow Pumps (150psi/5000gpm)

Floating Booster Pumps (Triton) - Supplies Low Pressure FLEX Pump (Dominator).

X X

X 5000 gpm 50 ft. lift Diesel Driven Low Pressure High Flow Suction Booster Pumps (5000gpm at 26 foot head)

Intermediate Pressure FLEX Pumps (Core Cooling Backup Pumps Non-Flood Event)

X X

150 gpm 350 PSIG (823 ft. TDH)

Diesel Driven SG Makeup/RCS Makeup Capable Pumps (500PSI/500gpm)

Intermediate Pressure FLEX Pumps (Core Cooling Backup Pump -

Flood Event)

X X

150 gpm 350 PSIG (823 ft. TDH) 480v AC See Above - SG Makeup/RCS Makeup Capable Pump (500PSI/500gpm) 1 Performance criteria of FLEX equipment is conservative and was determined during conceptual design as a basis for the selection of required FLEX equipment.

E2-74 of 84 PWR Portable Equipment Phase 3 Use and (potential/flexibility) diverse uses Performance Criteria 1 Phase 3 NSRC/SAFER Equipment or Other available offsite equipment.

List portable/pre-staged equipment Core Containment SFP Instrumentation Accessibility Mode 5 & 6 FLEX Pumps (RCS Core Cooling and Makeup Pumps - Non-Flood or Flood Event)

X 150 gpm 350 PSIG (823 ft. TDH) 480v AC See Above - SG Makeup/RCS Makeup Capable Pump (500PSI/500gpm)

High Pressure FLEX Pumps Backup (RCS Inventory Control)

X 40 gpm 600 PSIG (3561 ft. TDH) 480v AC High Pressure Injection Pump (1500PSI/60gpm)

Water Transfer Pumps Backup X

X 500 gpm 160 PSIG (374 ft. TDH)

Diesel Driven Low Pressure Medium Flow Pumps (300PSI/2500gpm)

Fuel Transfer Equipment x

Fuel Tankers x

Diesel Fuel Oil Transfer Pumps X

X X

2 - Tankers - 500 gallons Minimum each Transfer Pumps - 1 Diesel Driven and 1 Portable Electric Portable Diesel Fuel Tanks with Fuel Transfer Pumps (364 gallon tank with AC/DC powered transfer pumps)

Reverse Osmosis Unit/

Water Purification (provide makeup to the AFWST and/or water for blending borated makeup for the RCS)

X X

The Reverse Osmosis unit will have an output flow capacity of 250 gpm.

Portable makeup water treatment system capable of supplying purified water.

E2-75 of 84 Phase 3 Response Equipment/Commodities Item Notes Radiation Protection Equipment x

Survey instruments x

Dosimetry x

Off-site monitoring/sampling x

Radiological counting equipment x

Radiation protection supplies x

Equipment decontamination supplies x

Respiratory protection x

Portable Meteorological (MET) Tower.

Commodities x

Food o Meals Ready to Eat (MRE) o Microwaveable Meals x

Potable water Fuel Requirements x

Diesel Fuel Heavy Equipment x

Transportation equipment o

4 wheel drive tow vehicles x

Debris clearing equipment If the Equipment Support Services (ESS) facility located on the TVA Watts Bar Reservation survives the initiating event various pieces of heavy equipment will be available to assist in FLEX equipment and personnel deployment, debris removal, or other required remedial activities. Additionally, TVA as the largest public electrical power utility in the U. S. has access to heavy equipment, resources and other support services from its system wide transmission, hydro and fossil departments, other nuclear sites and its various service shops.

Communications Equipment x

Satellite Phones x

Portable Radios Portable Interior Lighting x

Flashlights x

Headlamps x

Batteries Portable Exterior Lighting x

Diesel generator powered light units NSRC will supply additional portable exterior light units.

E2-76 of 84 References 1.

NRC EA-12-049, Issuance of Order to Modify Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, March 12, 2012. [ADAMS Accession Number ML12054A735]

2.

NEI 12-06, Revision 0, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide, August 2012.

3.

NRC JLD-ISG-2012-01, Revision 0, Compliance with Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, August 2012.

4.

Watts Bar Nuclear Plant Updated Final Safety Analysis Report (UFSAR), Amendment 9, November 21, 2011.

5.

Watts Bar Nuclear Plant Unit 2 Final Safety Analysis Report (FSAR), Amendment 109.

6.

Not Used.

7.

Not Used.

8.

WCAP-17601-P, Revision 1, Reactor Coolant System Response to the Extended Loss of AC Power Event for Westinghouse, Combustion Engineering, and Babcock & Wilcox NSSS Designs, PWROG Project PA-ASC-0916, January 2013.

9.

LAR WBN-UFSAR-12-01, Application to Revise Watts Bar Nuclear Plant Unit 1 Updated Final Safety Analysis Report Regarding Changes to Hydrologic Analysis, TAC No.

ME8200,July 19, 2012. (Accession No. ML12236A167)

10. TVA Drawings a.

46W501-1, Revision J, Architectural Plan El 676.0 & 692.0.

b.

46W501-2, Revision J, Architectural Plan El 708.0 & 713.0.

c.

46W501-3, Revision K, Architectural Plan El 729.0 & 737.0.

d.

46W501-4, Revision K, Architectural Plan El 755.0 & 757.0.

e.

46W501-5, Revision F, Architectural Plan El 782.0 & 786.0.

f.

47W200-1, Revision 12, Equipment Plans - Roof

11. Replaced with References 18-20.

12. Task Interface Agreement (TIA) 2004-04, "Acceptability of Proceduralized Departures from Technical Specifications (TSs) Requirements at the Surry Power Station," (TAC Nos.

MC4331 and MC4332)," dated September 12, 2006. (Accession No. ML060590273)

13. OG-12-482, Revision 0, Transmittal of PA-PSC-0965 Core Team PWROG Core Cooling Management Interim Position Paper, November, 2012.

14. Sargent & Lundy Calculation, FLEX Implementation HVAC ELAP Analysis SL-01240, Revision 0, May 30, 2014, Project No. 12938-017.

15. AOI-40, Revision16, Station Blackout, March 1, 2012.

16. OG-12-515, Transmittal of Final Generic PWROG FLEX Support Guidelines and Interfaces (Controlling Procedure Interface and Recommended Instruments) from PA-PSC-0965, Revision 0, December 2012.

17. 1-ECA-0.0, Revision 0, Loss of Shutdown Power.

18. Westinghouse Calculation Note, CN-SEE-II-12-40, Revision 3, Determination of Time to Boil in the Watts Bar Spent Fuel Pool after an Earthquake.

19. Westinghouse Calculation Note, CN-SEE-II-12-20, Revision 2, Supporting Chemistry Calculations for Alternate Cooling Source Usage during Extended Loss of All A.C. Power at Watts Bar Nuclear Units 1 and 2.

20. Westinghouse Calculation Note, CN-SEE-II-13-26, Revision 1, Watts Bar Unit 1 and Unit 2 Reactor Coolant System FLEX Evaluation with Standard Reactor Coolant Pump Seals.

21. TVA Drawing 47E235-36, Environmental Data Environment

E2-77 of 84

22. Watts Bar White Paper - Liquefaction of Haul Routes for FLEX and Subsurface Investigation and Foundation Report for the Watts Bar Nuclear Plant Unit 1 Steam Generator Replacement Project. (EDMS 24900-100-KOR-CY00-00001).

23. NPG Calculation Record of Revision, MDQ00006720120190, Evaluation ERCW Availability during Extended Station Blackout.

24. Position Paper: Shutdown/Refueling Modes (Agency Wide Documents Access and Management Systems (ADAMS) Accession No. ML13273A514) and NRC Endorsement Letter (W50 140612 006) from Director of Mitigating Strategies Directorate, Office of Nuclear Reactor Regulation, September 30, 2013, ADAMS Accession No.; ML13267A382.

25. NRC Endorsement of EPRI Report; Augmented Approach for the Resolution of Fukushima NTTF Recommendation 2.1: Seismic, as an Acceptable Alternative to the March 12, 2012 Information Request, May 7, 2013.

26. TVA Calculation CDN 00 99 2013 000342 - Seismic Design Approach for Fukushima FLEX Equipment Installations in WBN Seismic Category I Structures, 9/30/2013.

27. NRC EA-12-051, Issuance of Order to Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, March 12, 2012 [ADAMS Accession Number ML12054A679].

28. NEI 12-02, Revision 1. Industry Guidance for Compliance with NRC Order EA-12-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, August, 2012.

29. NRC JLD-ISG-2012-03, Revision 0, Compliance with NRC Order EA-12-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, August, 2012.

30. TVA Calculations EDQ00023620070003, 125v DC Vital Battery System Analysis, Revision 028, EDMS T93140612006 and EPMMA041592, Station Blackout Coping Evaluation, Revision 020, EDMS T93140328014.

31. WBN SAFER/NSRC Playbook, SAFER Response Plan for Watts Bar Nuclear Plant, Revision 2, September 17, 2014.

32. 0 - FSI - 7, Loss of Vital Instrumentation or Control Power, Revision 0.

33. Response to NRC Staff Audit Question Clarification for Watts Bar Nuclear Plant, Units 1 and 2 Mitigation Strategies Integrated Plan, Phase 2 Electrical Strategy (TAC Nos. MF0950 and MF1177), March 28, 2014, Electrical Document Management System (EDMS) number L44 140328 003.

34. Watts Bar Nuclear Plant, Units 1 and 2 - Report For The Audit Regarding Implementation of Mitigating Strategies and Reliable Spent Fuel Instrumentation Related to Orders EA-12-049 and EA-12-051 (TAC Nos. MF0950, MF1177, MF0951 and MF1178), May 15, 2014,

[ADAMS Accession Number ML14128A129].

35. PWROG-14015, No. 1 Seal Flow Rate for Westinghouse Reactor Coolant Pumps Following Loss of All AC Power, Revision 0, June 2014, PA-SEE-1196.

36. Not Used

37. NPG-SPP-09.3.1, Guidelines for Preparation of Design Inputs and Change Impact Screen, Revision. 3, June 02, 2014.

38. NPG-SPP-07.2.11, Shutdown Risk Management, Revision. 5, June 30, 2014.

39. Wiring Diagrams Spent Fuel Pool Cooling Schematic Diagrams, 0-45W600-78-1.

40. CECC EPIP-3, Operations Duty Specialist Procedure for Alert, Site Area Emergency or General Emergency, Revision. 46, July 28, 2014.

41. Westinghouse Letter, LTR-ISENG-14-1, Revision 0, Containment Pressures and Temperatures for Watts Bar Units 1 and 2 during an ELAP Calculated with MAAP 4.07, February 27, 2014.

42. Westinghouse Calculation Note, CN-FSE-14-36, Watts Bar Units 1 and 2 As-Built FLEX System Fathom Model, Revision 0, October 17, 2014.

43. Westinghouse Letter, LTR-FSE-14-49, Response to FLEX Licensee Identified Open Item 10 in Support of the Overall Integrated Plan Submittal for Watts Bar Unit 1 and Unit 2, June 11, 2014.

44. TVA River Systems Operation procedure, RvM-SOP-10.05.06, Nuclear Notifications and Flood Warning Procedure, Revision 0001, September 02, 2014.

E2-78 of 84

45. Westinghouse Letter, LTR-SEE-II-14-44, Westinghouse Response to FLEX Audit Question 28, Licensee Identified Open Item 16, in Support of the Overall Integrated Plan Submittal for Watts Bar Units 1 and 2, Revision 0, July 31, 2014.

46. Westinghouse Calculation Note, CN-SEE-II-13-19, Best Estimate Condensate Use During an Extended Loss of AC Power Due to Decay Heat at Watts Bar Units 1 and 2, Revision 2, August 6, 2014.

47. OPDP - 8, Operability Determination Process and Limiting Conditions for Operation Tracking, Revision 0017, October 10, 2014.

48. NPG-SPP-07.3, Work Activity Risk Management Process, Revision 0016, October 07, 2014

49. LTR-SEE-II-14-10, Transmittal of Watts Bar RCS Makeup Boration Curves for a Beyond Design Basis Extended Loss of All AC Power Event (ELAP) to Support the FLEX Program, Revision 0, April 2, 2014.

50. NEI 12-01 Phase 2 Extended Loss of AC Power (ELAP) ERO Staffing Analysis Report, Revision 1, August 15, 2014.

51. Westinghouse NSAL-14-1, Impact of Reactor Coolant Pump No. 1 Seal Leakoff Piping on Reactor Coolant Pump Seal Leakage During Loss of All Seal Cooling, February 10, 2014.

52. Westinghouse Calculation Note, CN-PCSA-14-1, Transmittal of FLEX FSI Setpoints for ELAP, Revision 1, June 16, 2014.

53. 0 - FSI - 12, Alternate Containment Cooling, Revision 0.

54. 0 - FSI - 5.05, ERCW Alignment for 5000GPM Portable Diesel Pump (5PDP), Revision 0.

55. PWROG - 14027-P, No. 1 Seal Flow Rate for Westinghouse Reactor Coolant Pumps Following Loss of All AC Power, Revision 2, October 2014, PA-SEE-1196.

E2-79 of 84 Open Items Open item Number Description Status Notes 1

The current condensate storage tank (CST) is a non-seismic tank that is not missile protected. The site is currently pursuing two options; the qualification and hardening of the existing CST or the construction of a new seismically qualified and missile protected CST. One of these options must be completed before the volume of the CST can be credited.

Closed A new seismically qualified and hardened 500,000 gallon Auxiliary Feedwater Supply Tank (AFWST) has been constructed.

DCN 60060 & DCN 62324 for AFW Supply Tank DCN 61422 for tie in to existing Unit 1 plant piping.

2 Liquefaction of haul routes for FLEX will be analyzed.

Closed See Reference 22 3

No detailed analysis has been provided regarding initial FLEX fuel supplies to determine a need time for access to 7 day tank supplies or resupply of the 7 day tanks. It is assumed that each FLEX component is stored with a minimum supply of 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months of fuel at constant operation. This assumption will need to be assessed once all FLEX equipment has been purchased and equipment specifications are known.

Closed Fuel consumption spreadsheet completed to show that fuel supply will last seven days.

4 No need time has been identified for action to protect containment. This includes actions to mitigate pressurization of containment due to steaming when reactor coolant system (RCS) vent paths have been established or actions to mitigate temperature effects associated with equipment survivability. An evaluation will be provided to prove indefinite containment coping.

Closed See Reference 41 5

The Phase 3 equipment staging area has not been determined.

Closed Areas are identified and will be included with the Regional Response Center (NSRC) playbook. See Reference 31.

6 A strategy for clearing and removing debris will be determined.

Closed Debris removal equipment is identified and storage determined.

7 A thorough analysis of the makeup flow rate requirements and other equipment characteristics will be finalized during the detailed design phase of FLEX.

Closed Detailed FLEX Operating Conditions and pump sizing has been completed (See Reference 20).

E2-80 of 84 Open item Number Description Status Notes 8

The need time for spent fuel pool (SFP) cooling actions (deployment of hose, venting, and alignment of makeup) was determined using worst case heat loads. This item will continue to be assessed and later action times may be acceptable. Note that the timing for this step during an outage is different, but resources will be available to complete the required actions.

Closed See Reference 18.

9 Functional requirements for each of the Phase 3 strategies, equipment and components will be completed at a later time and will be provided in the six month updates to the February 28, 2013 submittal.

Closed See Reference 31.

10 Containment temperature instrumentation is only available until flood waters enter the technical support center (TSC) inverter or station battery rooms. A method to monitor containment temperature, post-flood, will be developed.

Closed See Reference 41 Section 5.3, and Reference 43.

11 The heating, ventilation and air conditioning (HVAC) analysis is preliminary, and has not been finalized.

Closed Calculation ID:

MDQ0003602013000272. RIMS #:

130830 801.

12 Verify ability to deploy FLEX equipment to provide core cooling in Modes 5 and 6 with steam generators (SGs) unavailable. If it is determined that gravity feed is not effective to cool the RCS and prevent fuel damage, Watts Bar will take actions to proceduralize administrative controls to pre-stage FLEX equipment prior to entering a condition where the SGs cannot provide adequate core cooling.

Closed See Reference 38.

E2-81 of 84 Open item Number Description Status Notes 13 An evaluation of the impact of FLEX response actions on design basis flood mode preparations will be performed. This evaluation will include the potential for extended preparation time for FLEX.

Changes which affect the Integrated Plan will be included in the six month update.

Closed TVAs River Systems Operation (RSO) will notify the WBN control room if Watts Bar Hydro instantaneous flow rate reaches 170,000 cfs, which approximates the 25 year flood frequency based upon observed historical flow data. This notification will provide for initiation and completion of preparatory FLEX equipment deployment and mitigation strategy implementation prior to conditions that might trigger a Stage 1 Flood Warning from RSO. See Reference 44.

14 Further analysis will be performed to determine the required timeline for implementing the 6.9 KV FLEX diesel generators (DGs) as an alternate power source for the loads supplied by the 480 V FLEX DGs.

Closed The revised timelines show that the 6.9 KV FLEX DGs are available within 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months . Updated sequence of events for both flood and non-flood conditions have been completed by TVA. They are added to this letter in A, Sequence of Events Timeline.

15 The CETs are only available until water enters the auxiliary instrument room. A method to monitor CET, post flood, will be evaluated and developed, if required.

Closed CETs will not be required for flood event.

16 Strategies to address extreme cold conditions on the refueling water storage tank (RWST) and/or boric acid tanks (BATs), including potential need to reenergize heaters have not been finalized.

Closed The RWST will remain above freezing and boric acid precipitation will not occur for the duration of the phase 2 coping strategy. The BAT which is located in the AB below plant grade elevation will remain a reasonable and justified back-up strategy. See Reference 45.

17 Establish an agreement with the Strategic Alliance for FLEX Emergency Response (SAFER) team in accordance with the requirements of Section 12 of NEI 12-06.

Closed Agreement with Regional Response Center (NSRC) is in place. See Reference 31.

18 Manual station blackout (SBO) load shedding time in References 4 and 5, Section 8.3.2.1.1, will be revised from 30 minutes to 45 minutes as supported by the 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months extended loss of alternating current power (ELAP) battery calculations.

Closed This item from the initial OIP submittal is no longer applicable since Watts Bar is no longer required to perform the initial SBO load shed.

See Reference 30.

E2-82 of 84 ACRONYMNS AB auxiliary building ABMT auxiliary boration makeup tank AC alternating current ACR auxiliary control room ACS alternate coolant system ADAMS agency wide documents access and management systems AFW auxiliary feedwater AFWST auxiliary feedwater supply tank AOI abnormal operating instruction AOP abnormal operating procedure AOV air-operated valve APM available physical margin ARV atmospheric relief valve AUO assistant unit operator BAT boric acid tank BCS backup control station BDB beyond-design-basis BDBEE beyond-design-basis external events CAS central alarm station CCS component cooling system CCW condenser circulating water CFR Code of Federal Regulations CFS cubic feet per second CLA cold leg accumulator CLB current licensing basis CST condensate storage tank CVCS chemical and volume control system CWST cask washdown storage tank DBFL design basis flood level DBE design basis event DC direct current DCN design change notice DG diesel generator DGB diesel generator building DWHT demineralized water head tank DWST demineralized water storage tank EBL emergency battery lighting EDG emergency diesel generator EDC engineering document change EDCR engineering document construction release EDMG extreme damage mitigation guideline EDMS electronic document management system EFW emergency feedwater ELAP extended loss of ac power EOI emergency operating instruction EOP emergency operating procedure EP emergency planning EPRI Electric Power Research Institute ERCW essential raw cooling water

E2-83 of 84 ERO emergency response organization ESF engineered safety feature FESB FLEX equipment storage building FLEX Flexible and Diverse Coping Mitigation Strategies FMBMS flood mode boration makeup system FSG FLEX support guideline FSI FLEX support instructions HCLPF high confidence of low probability failure HPFP high pressure fire protection HP FLEX Pump high pressure (HP) FLEX pump HVAC heating, ventilation, and air conditioning IER Industry Event Report INPO Institute of Nuclear Power Operations IP FLEX Pump intermediate pressure (IP) FLEX pump IPS intake pumping station ISG Interim Staff Guidance LCV level control valve LOCA loss of coolant accident LOOP loss of offsite power LP FLEX Pump low pressure (LP) FLEX pump LUHS loss of normal access to the ultimate heat sink MCC motor control centers MCR main control room MDAFWP motor driven auxiliary feedwater pump MOV motor operated valve MRE meals ready to eat MSL mean sea level MSVV main steam valve vault NEI Nuclear Energy Institute NPSH net positive suction head NRC Nuclear Regulatory Commission NSRC National SAFER Response Center NSSS nuclear steam supply system NTTF Near-Term Task Force OBE operating basis earthquake OPDP operability determination process OSC operation support center PD positive displacement PIC post issuance change PORV power operated relief valve PMF probable maximum flood PMP probable maximum precipitation PRA probabilistic risk assessment PWR pressurized water reactor PWROG Pressurized Water Reactor Owners Group PWST primary water storage tank QR quality related RCP reactor coolant pump RCS reactor coolant system RHR residual heat removal RSO River Systems Operation

E2-84 of 84 RWST refueling water storage tank RWT raw water tank SAFER Strategic Alliance for FLEX Emergency Response SAMG severe accident management guideline SBO station blackout SFP spent fuel pool SG steam generator SIP safety injection pump SIS safety injection system SPP standard department procedure SPRA seismic probabilistic risk assessment SR safety related SRO senior reactor operator S/RVs safety/relief valves SSC systems, structures and components SSE safe shutdown earthquake TD turbine-driven TDH total dynamic head TSC technical support center TDAFWP turbine driven auxiliary feedwater pump TOAF top of active fuel TVA Tennessee Valley Authority TWST tritiated water storage tank UFSAR updated final safety analysis report UHS ultimate heat sink

E2A1A-1 of 15 A Sequence of Events Timeline Non-Flood Event Action Item(s)

Elapsed Time from Event Initiation (T-0)

Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 0

Event Starts N

NA Plant @100% power 0

SBO N

NA ECA-0.0 (Reference 17) 1 Within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months of T-0 Declare ELAP Y

Equal to or Less Than 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from T-0 ELAP entry can be verified by control room staff when it is validated that Off-Site Power, Generation (switchyard) and the Emergency Diesel Generators (EDGs) are not available.

This declaration needs to occur within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from T-0 to provide operators with guidance to perform ELAP actions.

2 0.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Align and place in service the 480v FLEX Diesel Generators (DGs)

Y 0.75 hours8.680556e-4 days 0.0208 hours 1.240079e-4 weeks 2.85375e-5 months This provides charging current to the 125v DC Vital Batteries and ensures 125v DC Vital Battery power (control) and through the Vital Inverters 120v AC Vital Instrument Power (instrument indication).

3 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Verify 125v DC Vital Battery Chargers energized and supplying required load to the 125v DC Vital Batteries.

IF not, THEN complete ELAP Load Shed (Extended Load Shed) for any Vital Battery not being supplied its required load.

Y Complete within 1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months of T-0 Minimum duration 0.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months .

This step ensures each 125v DC Vital Battery Charger once picked up by its designated 480v FLEX DG is charging its designated Vital Battery. If not, then the ELAP Load Shed must be completed within 90 minutes (1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months ) from T-0 for the affected battery (ies). This ensures an 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months coping time for the affected 125v DC Vital Battery (ies).

E2A1A-2 of 15 Action Item(s)

Elapsed Time from Event Initiation (T-0)

Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 4 & 5 0.5 hour5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Damage Assessment and FLEX Equipment Staging N

2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Watts Bar has developed a post event damage assessment procedure. The damage assessment will evaluate and document the condition of plant systems, structures and components (SSCs) after an ELAP event. FLEX equipment staging locations and access routes will be a priority for the damage assessment. This assessment will facilitate debris removal, if required, to support FLEX equipment deployment.

6 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Stage and align Low Pressure (LP)

FLEX pumps (Triton and Dominator)

Y 4.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months LP FLEX Pumps staged and aligned to take suction from the intake channel with discharge hoses routed to the Essential Raw Cooling Water (ERCW) FLEX connections inside the Intake Pumping Station (IPS). An alternate or additional raw water source could come from the CCW Cooling Tower basin supplying suction to a LP FLEX Pump (Dominator) with its discharge hoses routed to FLEX (or B.5.b) connections at the 5th DG Building.

E2A1A-3 of 15 Action Item(s)

Elapsed Time from Event Initiation (T-0)

Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 7

Within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months of T-0 RCS Depressurization and Cooldown.

Y 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months At rated RCS pressure a potential leakage rate of 20.3 gpm per RCP following the event is possible. At a cold leg pressure of 1485 psig a potential leakage rate of 23.6 gpm per RCP is possible. (Reference 35 & Reference 55) RCS cooldown rate of 75 to 100° F/hr should be sustained until stabilized at ~ 300 psig SG pressure. Maintain RCS pressure greater than 250 psig to avoid Cold Leg Accumulator nitrogen injection into the RCS. Cooldown and depressurization should be stabilized within T+4 hours.

8 1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months 6.9KV FLEX DGs (FESB), kirk-key transfer switches (EDG Bldg.) and 6.9 KV Shutdown Boards, emergency feeder breakers and 480 V Shutdown Board Alignment (Shutdown Board Rooms).

Y 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months This is to ensure switching at the DG building and shutdown board rooms are complete, potential board loading is reduced and interlocks are cleared to allow the emergency feeder breakers to be used to safely power the 6.9 KV Shutdown Boards from the 6.9KV FLEX DGs.

9 3.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Energize the 6.9 KV Shutdown Boards with the 6.9KV FLEX DGs. Place the following components in service and restore RCS pressurizer level:

x Component Cooling System (CCS)

Pumps.

x Safety Injection Pumps (SIPs), as required to recover and maintain RCS pressurizer level.

Y 1.5 hour5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Action initiated is to support operation of the SIP providing restoration of RCS inventory, compensating for potential RCP seal leakage and shrinkage from cooldown.

E2A1A-4 of 15 Action Item(s)

Elapsed Time from Event Initiation (T-0)

Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 10 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Reduce SG Pressure to 160 psig per ECA-0.0.

N 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months This action occurs after RCS inventory has been restored by SIP operation, calculated boration and required mixing are completed and CLAs isolated to ensure against nitrogen injection into the RCS.

Note: The MDAFWPs and the Auxiliary Air Compressors can be placed in service and serve as the secondary or backup SG makeup source, if required.

11 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Place the following equipment in service, if required. Verify 6.9KV FLEX DG loading between component starts.

x Auxiliary Air Compressors x

Motor Driven Auxiliary Feedwater Pumps (MDAFWP) x Spent Fuel Pool (SFP) Cooling Pump (Restore SFP cooling).

N 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Action initiated, if required, to support repowering various installed pumps to facilitate ease of operation and provide indefinite coping capability.

12 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months Complete 480v FLEX DGs power and fuel line routing and connections (between EDG Building south wall and AB north wall) and replace hose and cable routing protective covers.

Complete alignments and verify DGs day tank fuel oil makeup.

Y 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Required to ensure continuous fuel supply from the EDG 7-day tanks to the 480v FLEX DGs day tanks. Note that this activity could be initiated earlier if maintenance resources are available.

E2A1A-5 of 15 Action Item(s)

Elapsed Time from Event Initiation (T-0)

Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 13 & 20 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Initiate alignment of ERCW headers to ensure cooling water supplied by the LP FLEX Pumps is effectively directed to support FLEX Strategies.

N 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months The realignment of ERCW headers are parallel responsibilities for assigned AUOs and ROs.

The majority of the realignment will be accomplished by closure of MOVs once the Reactor MOV Boards are repowered by the 6.9KV FLEX DGs.

14 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Stage and align the High Pressure (HP)

FLEX Pumps with suction from Refueling Water Storage Tank (RWST)

FLEX connections. {Alternate is from the Boric Acid Tank (BAT) FLEX connection for boration}.

N 2.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months The HP FLEX pump discharge hose can be routed to either Safety Injection Pumps discharge header FLEX connection. HP FLEX Pump capability is sufficient to maintain RCS inventory once the RCS is depressurized.

Makeup is required to compensate for cooldown (shrinkage and boration). Once RCS inventory is recovered the HP FLEX Pumps can maintain RCS inventory. Hoses will remain isolated and pumps out of service until required.

15 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Stage and align the Intermediate Pressure (IP) FLEX pumps at the Auxiliary Feedwater Supply Tank (AFWST) for backup for SG makeup (backup to the TDAFWP (or)

MDAFWPs).

N 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months Suction is aligned from the AFWST. The IP FLEX pump discharge can be routed to FLEX connections upstream of the TDAFWP Level Control Valves (LCV) (primary) or upstream of the MDAFWP LCVs (secondary).

This is a contingency in case of loss of the normal SG makeup capabilities. Hoses will remain isolated and pumps out of service until required.

E2A1A-6 of 15 Action Item(s)

Elapsed Time from Event Initiation (T-0)

Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 16 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Deploy hoses and spray nozzles as a contingency for SFP makeup.

Y 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Hoses will be routed from an Auxiliary Building elevation 757 ERCW FLEX connection to the SFP area or from an elevation 737 ERCW FLEX connection to the demineralized water FLEX connection on elevation 737 to allow makeup to the SFP.

17 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Initiate fueling operations for diesel powered FLEX equipment.

N Continuous from initiation This will need to be established within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months of initiation of diesel power FLEX equipment operation. Note that this action could be initiated earlier in the event if resources are available.

18 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Makeup to the AFWST will need to be evaluated. The AFWST provides approximately 15 hours1.736111e-4 days 0.00417 hours 2.480159e-5 weeks 5.7075e-6 months for 2 unit operation. If the Condensate Storage Tanks survive the event an additional inventory of quality water will be available, allowing additional time for makeup to the AFWST. (Reference 46).

N Continuous from initiation Sources of makeup to the AFWST are identified and FLEX connections are provided to facilitate transfer of quality water.

Alignment to the ERCW system, an ultimate heat sink source, via the LP FLEX pumps remains an option.

19 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Initiate portable lighting for MCR, Shutdown Board Room and FLEX equipment locations, as required.

N Continuous from initiation This is not a time constraint. MCR and Shutdown Board Rooms are provided with battery backup lighting. Portable lighting for FLEX equipment staging locations could be required. Portable lighting will be available for internal and external service, if required.

E2A1A-7 of 15 Action Item(s)

Elapsed Time from Event Initiation (T-0)

Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 21 - 24 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Monitor TDAFWP Room, Main Control Room (MCR), Shutdown Board Room, Vital Battery Board Room and SFP area ventilation needs.

N Continuous from initiation If required, verify 6.9KV FLEX DG loading and restore selected heating, ventilation and air conditioning (HVAC) systems to service.

(Reference 14) 25 & 26 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Evaluate, identify and address long term (within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months ) needs including:

x Mobile water purification unit x

Site diesel and gasoline fuel service.

N Continuous

E2A1A-8 of 15 A Sequence of Events Timeline Flood Event Action Item(s)

Elapsed Time from Event Initiation T-0 Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability Note: An ELAP could occur at anytime during flood preparation or a flood event therefore FLEX equipment and strategies must be staged and ready for implementation if required.

Note: The scenario described below assumes an ELAP event occurs post initial flood warning received from TVAs River System Operations and prior to a Stage 1 warning notification. This provides a 27 hour3.125e-4 days 0.0075 hours 4.464286e-5 weeks 1.02735e-5 months period before flood waters reach grade elevation. This flood preparation time period allows for initial use of the same strategy as a non-flood event for Steps 1-9 for stabilizing the plant and staging FLEX equipment for flood mitigation strategy.

Note: The permanent plant equipment incorporated into FLEX strategies that are located below Probable Maximum Flood (PMF) elevation and not designed for submerged operation will be removed from service and protection transitioned to flood capable FLEX equipment and strategies prior to flood waters reaching plant grade.

0 Event Starts NA NA Plant @100% power 0

SBO N

NA ECA-0.0 (Reference 17) 1 Within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months of T-0 Declare ELAP Y

Within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months of T-0 ELAP entry can be verified by control room staff when it is validated that Off-Site Power, Generation (Switchyard) and the Emergency Diesel Generators (EDGs) are not available.

This declaration needs to occur within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from T-0 to provide operators with guidance to perform ELAP actions.

E2A1A-9 of 15 Action Item(s)

Elapsed Time from Event Initiation T-0 Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 2

0.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Align and place in service the 480v FLEX Diesel Generators (DGs)

Y 0.75 hours8.680556e-4 days 0.0208 hours 1.240079e-4 weeks 2.85375e-5 months This provides charging current to the 125v DC Vital Batteries and ensures 125v DC Vital Battery power (control) and through the Vital inverters 120v AC Vital Instrument Power (instrument indication).

3 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Verify 125v DC Vital Battery Chargers energized and supplying required load to the 125v DC Vital Batteries.

IF not, THEN complete Extended Load Shed for any Vital Battery not being supplied its required load.

Y Complete within 1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months of T-0 Minimum duration 0.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months This step ensures each 125v DC Vital Battery Charger once picked up by its designated 480v FLEX DG is charging its designated Vital Battery. If not, then the ELAP Load Shed must be completed within 90 minutes (1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months ) from T-0 for the affected battery (ies). This ensures an 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months coping time for the affected 125v DC Vital Battery(ies).

4 & 5 0.5 hour5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Damage Assessment and FLEX Equipment Staging N

2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Watts Bar has developed a post event damage assessment procedure. The damage assessment will evaluate and document the condition of plant systems, structures and components (SSCs) after an ELAP event.

FLEX equipment staging locations and access routes will be a priority for the damage assessment. This assessment will facilitate debris removal, if required, to support FLEX equipment deployment.

E2A1A-10 of 15 Action Item(s)

Elapsed Time from Event Initiation T-0 Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 6

1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Stage and align Low Pressure (LP)

FLEX pumps (Dominator and Triton)

Y 4.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Staged and aligned to take suction from the intake channel and discharge routed to the Essential Raw Cooling Water (ERCW) FLEX connections at the Intake Pumping Station (IPS). And/or stage and align a Dominator LP FLEX Pump with suction from the CCW Cooling Tower basin and discharge hoses routed to FLEX (and/or B.5.b) connections at the 5th DG Building. Prior to flood waters exceeding the IPS staging location the LP FLEX Pumps staged there should be removed from service, IPS FLEX connection valves isolated and pumps restaged above PMF for future use.

7 Within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months of T-0 RCS Depressurization and Cooldown.

Y 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months At rated RCS pressure a potential leakage rate of 20.3 gpm per RCP following the event is possible. At a cold leg pressure of 1485 psig a potential leak rate of 23.6 gpm per RCP is possible. A RCS cooldown rate of 75 to 100° F/hr should be sustained until stabilized at ~ 300 psig SG pressure.

Maintain RCS pressure greater than 250 psig to avoid Cold Leg Accumulator nitrogen injection into the RCS. Cooldown and depressurization should be stabilized within T+4 hours.

E2A1A-11 of 15 Action Item(s)

Elapsed Time from Event Initiation T-0 Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 8

1.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months 6.9KV FLEX DGs (FESB), kirk-key transfer switches (EDG Bldg.) and 6.9 KV Shutdown Boards, emergency feeder breakers and 480 V Shutdown Boards alignment (Shutdown Board Rooms).

Y 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months This is to ensure switching at the DG building and shutdown board rooms are complete, potential board loading is reduced and interlocks are cleared to allow the emergency feeder breakers to be used to safely power the 6.9 KV Shutdown Boards from the 6.9 KV FLEX DGs.

9 3.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Energize the 6.9 KV Shutdown Boards with the 6.9KV FLEX DGs. Place the following components in service and restore RCS pressurizer level:

x Component Cooling System (CCS)

Pumps.

x Safety Injection Pumps, as required to recover and maintain RCS pressurizer level.

Y 1.5 hour5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Action initiated to support repowering installed pumps to restore RCS inventory.

10 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Reduce SG Pressure to 160 psig per ECA-0.0 N

2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months This action occurs after RCS inventory has been restored by SIP operation, calculated boration and required mixing are completed and CLAs isolated to ensure against nitrogen injection into the RCS.

Note: The MDAFWPs and Auxiliary Air Compressors can be placed in service and serve as the secondary SG makeup source, if required.

E2A1A-12 of 15 Action Item(s)

Elapsed Time from Event Initiation T-0 Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 11 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Place the following equipment in service, if required. Verify 6.9KV FLEX DG loading between component starts.

x Auxiliary Air Compressors x

Motor Driven Auxiliary Feedwater Pumps (MDAFWP).

x Spent Fuel Pool (SFP) Cooling Pump (Restore SFP cooling).

N 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Action initiated to support repowering various installed pumps to provide coping capability until flood waters reach plant grade and transition to FLEX mitigation strategy occurs.

12 4

Complete 480v FLEX DGs power and fuel line routing and connections (between EDG Building south wall and AB north wall) and replace hose and cable routing protective covers.

Complete alignments and verify DGs day tank fuel oil makeup.

Y 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Required to ensure continuous fuel supply from the EDG 7-day tanks to the 480v FLEX DGs day tanks. Note that this activity could be initiated earlier if maintenance resources are available 13 &

21 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Initiate alignment of ERCW headers to ensure cooling water supplied by the LP FLEX Pumps are effectively directed to support FLEX Strategies.

N 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months The realignment of ERCW headers are parallel responsibilities for assigned AUOs and ROs. The majority of the realignment will be accomplished by closure of MOVs once the Reactor MOV Boards are repowered by the 6.9KV FLEX DGs.

Note: If deployed, verify raw water supply to the ERCW headers from a LP FLEX Pump (Dominator) staged at the CCW Cooling Tower basin, isolate the ERCW FLEX connections inside the IPS and recover the LP FLEX Pumps (Dominator and Triton) staged at the Intake Pumping Station prior to flood waters exceeding their IPS deployment location. Relocate these pumps to the staging area north of the EDG Building (above PMF level).

E2A1A-13 of 15 Action Item(s)

Elapsed Time from Event Initiation T-0 Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 14 5.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Stage and align the following LP FLEX Pumps.

x A second set of Low Pressure (LP) FLEX Pumps (Dominator and Triton) staged on a pad just west of the 5th DG Building.

N 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Stage a second set of Low Pressure (LP)

FLEX Pumps Aligned to take suction from the road just South of the 5th Diesel Building with discharge routed to the Essential Raw Cooling Water (ERCW) FLEX (and/or B.5.b) connections inside the 5th DG Building.

Hoses will remain isolated and pumps out of service until required.

15 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Stage and align the 480v Motor Driven High Pressure (HP) FLEX pumps (AB elevation 692) with suction aligned from the Refueling Water Storage Tank (RWST) FLEX connections (AB elevation 692).

N 2.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months The HP FLEX pump discharge can be routed to either Safety Injection Pump discharge headers FLEX connection (B Train primary and A Train secondary). Makeup is required to compensate for cooldown (shrinkage and boration). Once RCS inventory is recovered the HP FLEX Pumps will maintain RCS inventory. Hoses will remain isolated and pumps out of service until required.

E2A1A-14 of 15 Action Item(s)

Elapsed Time from Event Initiation T-0 Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 16 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Stage and align the 480v motor driven Intermediate Pressure (IP) FLEX pumps (AB elevation 737) for makeup capability to the SGs.

N 2.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months Suction hoses are aligned from the AB elevation 737 ERCW FLEX connections.

The IP FLEX pumps discharge hoses can be routed to FLEX connection upstream of the TDAFWP Level Control Valves (LCVs)

(SMSVV elevation 729) (primary) or FLEX connections upstream of the MDAFWP LCVs (AB elevation 737) (secondary).

Hoses will remain isolated and pumps out of service until required.

17 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Deploy hoses (and if required, spray nozzles) as a contingency for SFP makeup.

Y 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Hoses will be routed from an Auxiliary Building elevation 757 ERCW FLEX connection to the SFP area or from an elevation 737 ERCW FLEX connection to the SFP demineralized water FLEX connection on elevation 737 to allow makeup to the SFP.

18 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Initiate fueling operations for diesel powered FLEX equipment.

N Continuous once initiated This will need to be established within 7 - 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months from initial operation of diesel powered FLEX equipment. Note that this action could be initiated earlier in the event if resources are available.

E2A1A-15 of 15 Action Item(s)

Elapsed Time from Event Initiation T-0 Action ELAP time constraint Y/N Task Duration (hours)

Remarks / Applicability 19 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Makeup to the AFWST will need to be evaluated. The AFWST provides approximately 15 hours1.736111e-4 days 0.00417 hours 2.480159e-5 weeks 5.7075e-6 months for 2 unit operation. If the Condensate Storage Tanks survive the event an additional inventory of quality water will be available prior to the requirement to makeup to the AFWST. (Reference 46).

N Continuous once initiated Sources of makeup to the AFWST are identified and FLEX connections are provided to facilitate transfer of quality water.

Alignment to the ERCW system an ultimate heat sink source via the LP FLEX pumps remains an option.

20 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Initiate portable lighting for MCR, Shutdown Board Room and FLEX equipment locations, as required.

N Continuous once initiated This is not a time constraint. MCR and Shutdown Board Rooms are provided with battery backup lighting. Portable lighting for FLEX equipment staging locations could be required. Portable lighting will be available for internal and external service, if required.

22, 23

& 24 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Monitor TDAFWP Room, Main Control Room (MCR), Shutdown Board Room, Vital Battery Board Room and SFP area ventilation needs.

N Continuous once initiated If required, verify 6.9 KV FLEX DG loading and restore selected heating, ventilation and air conditioning (HVAC) systems to service.

(Reference 14) 25 &

26 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months Evaluate, identify and address long term (within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months ) needs including:

x Mobile water purification unit x

Site diesel and gasoline fuel service.

N Continuous

E2A1B-1 of 1 B NSSS Significant Reference Analysis Deviation Table Item Parameter of interest WCAP value WCAP-17601-P, Revision 1, January 2013 (Reference 8)

NSAL-14-1, 02/10/2014 (Reference 51)

CN-SEE-II-13-26, Revision 1 (Reference 20).

WCAP page Plant applied value Gap and discussion There are no deviations.

E2A2-1 of 1 Milestone Schedule - Items Complete Milestone Completion Date Submit 60 Day Status Report Oct 2012 Submit Overall Integrated Implementation Plan Feb 2013 6 Month Status Updates Update 1 Aug 2013 Update 2 Feb 2014 Update 3 Aug 2014 FLEX Strategy Evaluation June 2013 Walk-throughs or Demonstrations Dec 2014 Perform Staffing Analysis June 2014 Modifications Modifications Evaluation Apr 2013 Unit 1 N-1 Walkdown Apr 2013 Unit 1 Design Engineering Oct 2013 Unit 1 Implementation Outage May 2014 Unit 2 Construction Walkdown Apr 2013 Unit 2 Design Engineering Feb 2014 Unit 2 Implementation (Startup)

Dec 20141 Storage Storage Design Engineering Storage Implementation Dec 20141 On-Site FLEX Equipment Purchase/Procure Dec 20141 Off-Site FLEX Equipment Develop Strategies with NSRC Sep 2014 Identify Off-Site Delivery Stations (if necessary)

Sep 2014 Procedures PWROG issues FLEX Support Guidelines (FSG)

Jun 2013 Create WBN FLEX Support Instructions (FSI)

Dec 20141 Create Maintenance Procedures Dec 20141 Training Develop Training Plan Apr 2014 Training Complete Dec 20141 Unit 1 FLEX Implementation Dec 20141 Unit 2 FLEX Implementation Dec 20141 Full Site FLEX Implementation Mar 20152 Submit Completion Report Mar 20152 1-TVA will provide a final Milestone Schedule - Items Complete table by December 17, 2014.

2-Full site FLEX implementation is tied to 30 days prior to U2 Operating License to allow for completion of pre-operational testing of U2 components.

ENCLOSURE 3 LIST OF COMMITMENTS

1. TVA will provide under separate cover a Table describing a summary answer for each of the open items that describes the documents which provided the technical basis for the answer by December 1, 2014.

2. TVA will provide a letter stating WBN is in full compliance with Order EA-12-049 and the open items described below are closed by December 17, 2014:

a. Modifications

b. Equipment - Procured and Maintenance and Testing c.

Protected Storage

d. Procedures

e. Training f.

Validation

g. FLEX Program Document

h. Final Integrated Plan, Attachment 2, Milestone Schedule - Items Complete Table E3-1 of 1 CNL-14-191

v t e Letter Sequence Other
TAC:MF0951, (Approved, Closed) TAC:MF0950, (Approved, Closed)
Initiation Request Acceptance Administration Questions 2 August 2013 24 October 2013 Answers 22 November 2013 10 January 2014 25 June 2014 6 September 2013 Results Approval Other: CNL-14-030, Second Six-Month Status Report in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051), CNL-14-131, Third Six-Month Status Report in Response to the March 12, 2012, Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051) for Watts Bar Nuclear Plant, CNL-14-191, Compliance Status Letter and Final Integrated Plan in Response to the March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049, CNL-14-192, Compliance Letter in Response to the March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051) for Watts Bar Nuclear Plant, CNL-14-232, Closure of Open Item Discussed in Tennessee Valley Authoritys Compliance Letter in Response to the March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order No. EA-12-051), ML12307A105, ML13063A440, ML13247A288, ML13254A297, ML13261A038, ML14128A129
MONTHYEAR2014-01-10 [Table View]

CNL-14-191, Compliance Status Letter and Final Integrated Plan in Response to the March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049

Text

Subject:

References:

Enclosures:

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