NL-14-1989, Expedited Seismic Evaluation Process Report - Fukushima Near-Term Task Force Recommendation 2.1

Expedited Seismic Evaluation Process Report - Fukushima Near-Term Task Force Recommendation 2.1

ML15049A502
Person / Time
Site:	Hatch
Issue date:	12/30/2014
From:	Pierce C Southern Co, Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NL-14-1989
Download: ML15049A502 (72)

Text

Charles R. Pierce Southern Nuclear Regulatory Affairs Director Operating Company, Inc.

40 Inverness Center Parkway Post Office Box 1295 Birmingham , AL 35201 Tel 205.992.7872 Fax 205.992.7601 December 30, 2014 Docket Nos.: 50-321 NL-14-1989 50-366 U. S. Nuclear Regulatory Commission ATTN : Document Control Desk Washington, D. C. 20555-0001 Edwin I. Hatch Nuclear Plant- Units 1 and 2 Expedited Seismic Evaluation Process Report -

Fukushima Near-Term Task Force Recommendation 2.1

References:

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

2. NEI Letter to NRC, Proposed Path Forward for NTTF Recommendation 2.1:

Seismic Reevaluations, dated April 9, 2013.

3. NRC Letter, Electric Power Research Institute Final Draft Report XXXXXX, "Seismic Evaluation Guidance: Augmented Approach for the Resolution of Fukushima Near- Term Task Force Recommendation 2.1: Seismic" as an Acceptable Alternative to the March 12, 2012, Information Request for Seismic Reevaluations, dated May 7, 2013.

Ladies and Gentlemen:

On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued a request for information pursuant to 10 CFR 50.54(f) associated with the recommendations of the Fukushima Near-Term Task Force (NTTF) (Reference 1). Enclosure 1 of Reference 1 requested each licensee to reevaluate the seismic hazards at their sites using present-day NRC requirements and guidance, and to identify actions taken or planned to address plant-specific vulnerabilities associated with the updated seismic hazards.

The NRC endorsed the Electric Power Research Institute (EPRI) Report, Seismic Evaluation Guidance: EPRI Guidance for the Resolution of Fukushima Near- Term Task Force Recommendation 2 . 1: Seismic, Draft Report, as an acceptable alternative to the information requested in Reference 1 by letter dated May 7, 2013 (Reference 3). In its endorsement, the NRC staff determined that the EPRI Guidance will provide an important demonstration of seismic margin and expedite plant safety enhancements through evaluations and potential near-term modifications of certain core and containment cooling equipment while more comprehensive plant seismic risk evaluations are performed. Reference 3 also provided NRC staff approval of the schedule modifications requested by

U. S. Nuclear Regulatory Commission NL-14-1989 Page2 Reference 2. Based on the modified schedule, Central and Eastern United States (CEUS) licensees are required to submit the reports resulting from the Expedited Seismic Evaluation Process (ESEP) by December 2014. Accordingly, the Edwin I. Hatch Nuclear Plant ESEP Report for Units 1 and 2 is provided in . A table of outstanding actions required for completion of the ESEP activities, with a schedule for completion of each, is provided in Enclosure 2.

This letter contains NRC commitments described in Enclosure 3. If you have any questions, please contact John Giddens at 205.992.7924.

Mr. C. R. Pierce states he is the Regulatory Affairs Director for Southern Nuclear Operating Company, is authorized to execute this oath on behalf of Southern Nuclear Operating Company and, to the best of his knowledge and belief, the facts set forth in this letter are true.

Respectfull~ubmitted, c.-R. r~

C. R. Pierce Regulatory Affairs Director CRP/JMG/TWS ':1(.

to and subscribed before me this~ day of ~e,,er '2014.

My commission expires: I/l. /z.ot8

Enclosures:

1. Expedited Seismic Evaluation Process (ESEP) Report

2. Required Actions and Schedule for Completion of ESEP Activities

3. Table of Regulatory Commitments cc: Southern Nuclear Operating Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bost, Executive Vice President & Chief Nuclear Officer Mr. D. R. Vineyard, Vice President- Hatch Mr. M. D. Meier, Vice President- Regulatory Affairs Mr. D. R. Madison, Vice President- Fleet Operations Mr. B. J. Adams, Vice President- Engineering Mr. G. L. Johnson, Regulatory Affairs Manager- Hatch RType: CHA02.004 U. S. Nuclear Regulatorv Commission Mr. V. M. McCree, Regional Administrator Mr. R. E. Martin, NRR Senior Project Manager- Hatch Mr. D. H. Hardage, Senior Resident Inspector- Hatch State of Georgia Mr. J. H. Turner, Director- Environmental Protection Division

Edwin I. Hatch Nuclear Plant - Units 1 and 2 Expedited Seismic Evaluation Process Report -

Fukushima Near-Term Task Force Recommendation 2.1 Enclosure 1 Expedited Seismic Evaluation Process (ESEP) Report

• MPR ASSOCIATES INC.

ENGINEERS MPR-4121 Revision 0 December 23, 2014 Plant Hatch Units 1 and 2 Expedited Seismic Evaluation Process (ESEP)

Report QUALITY ASSURANCE DOCUMENT This document has been prepared, reviewed, and approved in accordance with the Quality Assurance requirements of 10CFR50 Appendix Band/or ASME NQA-1, as specified in the MPR Nuclear Quality Assurance Program.

Prepared for Southern Nuclear Operating Company

.MPR ASSOCIATES INC.

ENGINEERS Plant Hatch Units 1 and 2 Expedited Seismic Evaluation Process (ESEP)

Report MPR-4121 Revision 0 December 23,2014 QUALITY ASSURANCE DOCUMENT This document has been prepared, reviewed, and approved in accordance with the Quality Assurance requirements of 10CFR50 Appendix Band/or ASME NQA-1, as specified in the MPR Nuclear Quality Assurance Program.

Prepared by: f.~ Q '/{~

Kimberly A. Keithline Reviewed by: H. ~~

Mojtaba ghbaei Approved by: ~4.~

Caroline S. Schlaseman Prepared for Southern Nuclear Operating Company 320 KING STREET ALEXANDRIA, VA 22314-3230 703-519*0200 FAX: 703-519*0224 http:\\www.mpr.com

RECORD OF REVISIONS Revision Affected Pages Description 0 All Initial issue MPR-4121 iii RevisionO

Contents Executive Summary ...................................................................................................... 1 1 Purpose and Objective ......................................................................................... 2 2 Brief Summary of the FLEX Seismic Implementation Strategies ..................... 3 3 Equipment Selection Process and ESEL. ........................................................... 6 3.1 Equipment Selection Process and ESEL ...................................................................... 6 3 .1.1 ESEL Development ............................................................................................. 6 3 .1.2 Power Operated Valves ....................................................................................... 7 3.1.3 Pull Boxes ...........................................................................................................7 3.1.4 Termination Cabinets .......................................................................................... 8 3.1.5 Critical Instrumentation Indicators ..................................................................... 8 3.1.6 Phase 2 and Phase 3 Piping Connections ............................................................ 8 3.1.7 Inaccessible Valve Interlocks .............................................................................. 8 3.2 Justification for Use of Equipment that is not the Primary Means for FLEX lmplementation ....................................................................................................................... 8 4 Ground Motion Response Spectrum (GMRS) .................................................... 9 4.1 Plot of GMRS Submitted by Licensee .......................................................................... 9 4.2 Comparison to SSE ..................................................................................................... 10 5 Review Level Ground Motion (RLGM) ............................................................... 14 5.1 Description of RLGM Selected .................................................................................. 14 5.2 Method to Estimate In-Structure Response Spectrum (ISRS) .................................... 16 6 Seismic Margin Evaluation Approach ............................................................... 17 6.1 Summary of Methodologies Used .............................................................................. 17 6.2 HCLPF Screening Process .......................................................................................... 17 6.3 Seismic Walkdown Approach .................................................................................... 18 6.3.1 Walkdown Approach ........................................................................................ 18 6.3.2 Application ofPrevious Walkdown Information .............................................. 19 6.3.3 Significant Walkdown Findings ........................................................................ 20 MPR-4121 RevisionO

6.4 HCLPF Calculation Process ....................................................................................... 20 6.5 Functional Evaluation ofRelays ................................................................................. 20 6.6 Tabulated ESEL HCLPF Values (Including Key Failure Modes) ............................. 21 7 Inaccessible Items .............................................................................................. 22 7.1 Identification of ESEL Items Inaccessible for Walkdown ......................................... 22 7.2 Planned Walkdown!Evaluation Schedule/Close Out.. ................................................ 23 8 ESEP Conclusions and Results ........................................................................ 24 8.1 Supporting Information .............................................................................................. 24 8.2 Identification of Planned Modifications ..................................................................... 25 8.3 Modification Implementation Schedule ..................................................................... 25 8.4 Summary of Regulatory Commitments ...................................................................... 25 9 References .......................................................................................................... 26 Attachment A: Plant Hatch Unit 1 ESEL. .............................................................. A-1 : Plant Hatch Unit 2 ESEL. .............................................................. B-1 MPR-4121 v RevisionO

Tables Table 4-1. GMRS for Plant Hatch Units 1 and 2 ........................................................................... 10 Table 4-2. Horizontal Design Basis Earthquake (DBE) for Plant Hatch Unit 1............................ 12 Table 4-3. Horizontal Design Basis Earthquake (DBE) for Plant Hatch Unit 2 ............................ 13 Table 5-1. Plant Hatch IPEEE RLE ............................................................................................... 15 Table A-1. Plant Hatch Unit 1 ESEL Items and HCLPF Results ............................................... A-1 Table B-1. Plant Hatch Unit 2 ESEL Items and HCLPF Results ................................................B-1 MPR-4121 vi RevisionO

Figures Figure 2-1. Electrical Diagram for Plant Hatch FLEX Strategies (Reference 3) ........................... .4 Figure 2-2. Flow Diagram for Plant Hatch FLEX Strategies (Reference 3) .................................. .5 Figure 4-1. Plant Hatch GMR.S ........................................................................................................9 Figure 4-2. Horizontal Design Basis Earthquake (DBE) and GMR.S for Plant Hatch .................. 11 Figure 5-1. Hatch IPEEE RLE Compared to the Unit 1 and Unit 2 DBEs and the GMR.S ........... 15 MPR-4121 vii RevisionO

Executive Summary Plant Hatch Units 1 and 2 have performed the Expedited Seismic Evaluation Process (ESEP) as an interim action in response to the NRC's 50.54(f) letter (Reference 1). The purpose was to demonstrate seismic margin through a review of a subset of the plant equipment that can be relied upon to protect the reactor core following beyond design basis seismic events. The ESEP was performed using the methodologies in the NRC-endorsed industry guidance in EPRI 3002000704, Seismic Evaluation Guidance: Augmented Approach for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1 - Seismic (Reference 2). As a result of the ESEP, no modifications have been identified as necessary to meet ESEP acceptance criteria specified in Reference 2.

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1 Purpose and Objective Following the accident at the Fukushima Dai-ichi nuclear power plant resulting from the March 11,2011, Great Tohoku Earthquake and subsequent tsunami, the Nuclear Regulatory Commission (NRC) established a Near Term Task Force (NTTF) to conduct a systematic review ofNRC processes and regulations and to determine if the agency should make additional improvements to its regulatory system. The NTTF developed a set of recommendations intended to clarify and strengthen the regulatory framework for protection against natural phenomena.

Subsequently, the NRC issued a 50.54(f) letter on March 12, 2012 (Reference 1), requesting information to assure that these recommendations are addressed by all U.S. nuclear power plants.

The 50.54(f) letter requests that licensees and holders of construction permits under 10 CFR Part 50 reevaluate the seismic hazards at their sites against present-day NRC requirements and guidance. Depending on the comparison between the reevaluated seismic hazard and the current design basis, further risk assessment may be required. Assessment approaches acceptable to the staff include a seismic probabilistic risk assessment (SPRA) or a seismic margin assessment (SMA). Based upon the assessment results, the NRC staff will determine whether additional regulatory actions are necessary.

This report describes the Expedited Seismic Evaluation Process (ESEP) undertaken for Plant Hatch Units 1 and 2. The intent of the ESEP is to perform an interim action in response to the NRC's 50.54(f) letter (Reference 1) to demonstrate seismic margin through a review of a subset of the plant equipment that can be relied upon to protect the reactor core following beyond design basis seismic events.

The ESEP is implemented using the methodologies in the NRC-endorsed industry guidance in EPRI 3002000704, Seismic Evaluation Guidance: Augmented Approach for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1- Seismic (Reference 2).

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

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2 Brief Summary of the FLEX Seismic Implementation Strategies The Plant Hatch FLEX strategies for Reactor Core Cooling and Containment Function are summarized below. This summary is derived from the Plant Hatch Overall Integrated Plan (OIP) in Response to the March 12,2012, Commission Order EA-12-049 (Reference 3).

During FLEX Phase 1, the primary strategy for reactor core cooling is to supply high quality water via reactor core isolation cooling (RCIC) with suction from the Condensate Storage Tank (CST). lfthe CST is depleted (in approximately 6-7 hours by analysis), suction will be taken from the torus. Reactor pressure is controlled using safety relief valves (SRVs) with DC control power and pneumatic pressure supplied by the station batteries and accumulators for each SRV.

As torus temperature increases, operators reduce reactor pressure to 200-400 psig to provide margin to the heat capacity temperature limit curve.

During FLEX Phase 2, reactor core cooling will continue to be maintained using RCIC. After depletion of the initial CST inventory and while RCIC is taking suction from the torus, the CST will be replenished using the portable FLEX pump and water from the Ultimate Heat Sink (Altamaha River). RCIC will continue to inject water from the torus until the torus level reaches the low level limit and suction must be re-aligned to the CST. The torus water level drops due to evaporation through the Hardened Containment Vent System (HCVS), which is operated to maintain containment parameters below design limits and RCIC operating parameters within acceptable limits. Reactor pressure will continue to be controlled using the SRVs. The 125V DC batteries will provide power for more than 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> without recharging. As shown in Figure 2-1 (Reference 3), the FLEX 600 VDC diesel generators will be connected at approximately 10-12 hours to power two 125/250 VDC Battery Chargers per division, RCIC Controls, and other loads necessary for event mitigation and monitoring.

During FLEX Phase 3, reactor core cooling can be maintained using installed plant equipment and on-site portable FLEX equipment. RCIC will be used to cool the core until reactor pressure is insufficient to drive the RCIC turbine, at which time the Phase 2 FLEX pump will be used to inject directly to the reactor using the RHRSW-RHR cross tie valves as shown in Figure 2-2 (Reference 3); this will be well after 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> per analysis .

.MPR-4121 3 RevisionO

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MPR-4 12 1 Revi sion 0 5

3 Equipment Selection Process and ESEL The selection of equipment for the Expedited Seismic Equipment List (ESEL) followed the guidelines ofEPRI 3002000704 (Reference 2). The ESELs for Units 1 and 2, presented in Attachments A and B, respectively, are based on SNCH106:..PR-001 and SNCH106-PR-002 (References 4 and 5).

3.1 EQUIPMENT SELECTION PROCESS AND ESEL The ESEL component selection followed the EPRI guidance outlined in Section 3.2 of Reference 2. The selection of equipment to be included on the ESEL was based on installed plant equipment credited in the FLEX strategies during Phase 1, 2, and 3 mitigation of a Beyond Design Basis External Event (BDBEE), as outlined in the Plant Hatch Overall Integrated Plan (OIP) in Response to the March 12,2012, Commission Order EA-12-049 (Reference 3). The OIP provides the Plant Hatch FLEX mitigation strategy and serves as the basis for equipment selected for the ESEP.

The Plant Hatch ESEL includes permanently installed plant equipment that could be relied upon to accomplish the core cooling and containment safety functions identified in Table 3-1 of Reference 2 in response to a beyond-design-basis earthquake. Per Reference 2, the ESEL does not include portable or pre-staged FLEX equipment (not permanently installed) or equipment that is used only for recovery strategies. The scope of equipment on the ESEL includes that required to support a single FLEX success path. Instrumentation monitoring requirements for core cooling and containment integrity functions are limited to those discussed in Reference 2.

In accordance with Reference 2, the following structures, systems, and components were excluded from the ESEL:

• Structures (e.g., reactor building and control building)

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

• Manual valves and check valves

• Power-operated valves not required to change state as part of the FLEX mitigation strategies

• Nuclear steam supply system components (e.g., reactor pressure vessel and internals) 3.1.1 ESEL Development The ESEL was developed by reviewing the Plant Hatch FLEX OIP (Reference 3) to determine the major equipment involved in the FLEX strategies. Plant drawings (e.g., Process and MPR-4121 6 RevisionO

Instrumentation Diagrams (P&IDs) and electrical one-line diagrams) were reviewed to specify the boundaries of the flow paths used in the FLEX strategies and to identify other components needed to support operation of the systems credited in the FLEX strategies. Boundaries were established at an electrical or mechanical isolation device (e.g., isolation amplifier or valve) in branch circuits/branch lines off the defined strategy electrical or fluid flowpath. P&IDs were the primary reference documents used to identify mechanical components and instrumentation needed for FLEX. Once the flow paths were identified, specific components were selected using the guidance in Reference 2. Electrical components needed to support FLEX were identified using one-line diagrams and schematics. Based on this review, base list tables of components were developed for each of the methods credited with accomplishing key functions in the FLEX strategies.

The base list tables were then reviewed to determine which equipment should be included on the ESEL. Most of the equipment decisions were clearly outlined in the Reference 2 guidance; however, some judgments were necessary as discussed below.

3.1.2 Power Operated Valves Per the Reference 2 EPRI guidance, the ESEL does not need to include power-operated valves that are not required to change state as part of the FLEX mitigating strategies. However, Reference 2 also states, "In addition to the physical failure modes (load path and anchorage) of specific pieces of installed equipment, functional failure modes of electrical and mechanical portions of the installed Phase 1 equipment should be considered (e.g., RCIC)." Because relay chatter could cause a functional failure, the following criteria were used to determine whether specific power-operated valves should be included on the ESEL:

• Power operated valves in the primary success path will be included on the ESEL if they need to remain energized during Phase 1 in order to maintain core cooling and containment integrity (e.g., certain DC-powered valves).

• Power operated valves not required to change state as part of the FLEX mitigation strategies may be excluded from the ESEL if they would be de-energized by the event that causes the Extended Loss of all AC Power (ELAP) event.

• AC power-operated valves not required to change state as part of the Phase 1 FLEX mitigation strategies may be excluded from the ESEP if they are re-energized and operated during Phase 2 or 3 activities.

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

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3.1.4 Termination Cabinets Although termination cabinets and junction boxes provide a passive function similar to pull boxes, they were included on the ESEL to ensure industry knowledge on panel/anchorage failure vulnerabilities is addressed.

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

3.1.6 Phase 2 and Phase 3 Piping Connections As noted in Section 3.2 ofReference 2, the scope of the ESEL is limited to installed plant equipment and FLEX equipment connections" and "the selection process for the ESEL should assume the FLEX strategies (modifications, equipment, procedures, etc.) have been implemented." Section 3.2 of Reference 2 also explains that "piping, cabling, conduit, HV AC, and their supports" are excluded from the ESEL scope. Therefore, piping and pipe supports associated with FLEX Phase 2 and Phase 3 connections are excluded from the scope of the ESEP evaluation. Except as described in Sections 3.1 and 3 .1.2 above, valves required to change position to establish/maintain FLEX Phase 2 and Phase 3 flow paths (i.e., active valves) are included in the ESEL.

3.1.71naccessible Valve Interlocks Some components have interlocks that could potentially inhibit valve operation during Phase 2 or 3 of FLEX. Reference 2 specifically allows exclusion of interlock failures from the ESEL if plant procedures provide instructions for manual operation to ensure performance of the required FLEX function. For valves that cannot be operated locally due to location in containment or high radiation areas, this statement is interpreted as allowing the interlocks in the control circuit to be bypassed to allow remote manual operation. Therefore, these interlocks are excluded in Phase 3.

3.2 JUSTIFICATION FOR USE OF EQUIPMENT THAT IS NOT THE PRIMARY MEANS FOR FLEX IMPLEMENTATION All components on the ESEL for Plant Hatch Units 1 and 2 are associated with the primary FLEX strategies. Therefore, since no alternate equipment is being used, no justification is needed.

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4 Ground Motion Response Spectrum (GMRS)

In response to the 50. 54( f) letter (Reference 1), SNC reevaluated the Plant Hatch seismic hazard in accordance with the NRC-endorsed industry guidance (Reference 6).

4.1 PLOT OF GM RS SUBMITTED BY LICENSEE The plot of the Plant Hatch GMRS submitted by SNC to the NRC in Reference 7 is shown in Figure 4-1. Table 4-1 contains the corresponding numerical values that were also included in Reference 7. The GMRS and Design Basis Earthquake (DBE) control point elevation is defined at Elevation 129 feet, which is general plant grade.

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Table 4-1. GMRS for Plant Hatch Units 1 and 2 Frequency Spectral Frequency Spectral Frequency Spectral (Hz) Acceleration (Hz) Acceleration (Hz) Acceleration (g) (g) (g) 100 0.1422 12.5 0.2744 1*_,:_: ,1.00 0.2206 90.0 0.1422 10.0 0.3039 0.900 0.2171 80;0 0.1427 9.00 0.3111 0.800 0.2009 70.0 0.1438 cC:C.

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15.0 0.2459 . 1.25 0.2654 4.2 COMPARISON TO SSE The plots of the Plant Hatch Unit 1 DBE and Unit 2 DBE submitted by SNC to the NRC in Reference 7 are shown in Figure 4-2 along with the GMRS. Tables 4-2 and 4-3 contain the corresponding numerical values that were also included in Reference 7. Note that Reference 7 uses DBE and SSE interchangeably for Plant Hatch.

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Table 4-2. Horizontal Design Basis Earthquake (DBE) for Plant Hatch Unit 1 Frequency (Hz) Spectral Frequency (Hz) Spectral Acceleration (g) Acceleration (g) 33.33 0.150 3.33 0.221 28.67 0.150 2.86 0.225 25.00 0.150 2.50 0.221 22.22 0.150 2.22 0.216 20.00 0.150 2.00 0.206 16.67 0.150 1.67 0.1 78 14.29 0.150 1.43 0.165 12.50 0.156 1.25 0.150 11.11 0.163 1.11 0.133 10.00 0.169 1.00 0.128 8.00 0.188 0.67 0.092 6.67 0.206 0.50 0.069 5.00 0.216 0.33 0.051 4.00 0.221 0.10 0.015 MPR-4121 12 Revision 0

Table 4-3. Horizontal Design Basis Earthquake (DBE) for Plant Hatch Unit 2 Frequency (Hz) Spectral Frequency (Hz) Spectral Acceleration (g) Acceleration (g) 100.00 0.150 2.50 0.320 16.00 0.150 2.00 0.320 14.30 0.165 1.50 0.240 12.50 0.180 1.25 0.200 11.10 0.200 1.00 0.160 10.00 0.210 0.70 0.110 8.30 0.240 0.50 0.080 7.70 0.260 0.33 0.050 6.00 0.320 0.22 0.036 5.00 0.320 0.14 0.015 4.00 0.320 0.10 0.007 3.00 0.320 MPR-4121 13 Revision 0

5 Review Level Ground Motion (RLGM)

Section 4 of Reference 2 states that the ESEP may be performed using either the GMRS or a linearly scaled version of the SSE (DBE for Plant Hatch) that bounds the GMRS between 1 and 10 Hz. In many cases, scaling the SSE facilitates a more expedient evaluation by allowing use of existing SSE-based in-structure response spectra (ISRS) that are simply scaled by the same factor (Scenarios 2 and 3 in Figure 1-2 of Reference 2). However, for surface-mounted items (where ISRS estimates are not necessary), plants may decide to use the GMRS instead of the scaled SSE (Scenario 4 in Figure 1-2 ofReference 2).

The Plant Hatch ESEP was performed using either the GMRS (for two surface-mounted items) or the RLGM used previously by the combined A-46/IPEEE Program at Plant Hatch as discussed below, which is consistent with the guidance in Reference 2.

5.1 DESCRIPTION

OF RLGM SELECTED As discussed in Reference 7 and documented in the 1991 EPRI Report NP-721 7 (Reference 8), a full EPRI Seismic Margin Assessment (SMA) was previously performed for Plant Hatch Unit 1 as a trial BWR assessment of the EPRI SMA methodology. That SMA project included a soil failure evaluation and a full relay evaluation and was peer reviewed by several review panels.

As part of the Independent Plant Examination of External Events (IPEEE), a focused scope SMA and a full SQUG GIP relay review were performed for Plant Hatch Unit 2 (Reference 9). The Review Level Earthquake (RLE) for both of those SMAs was a median NUREG/CR-0098 type ground response spectrum anchored to 0.3g peak ground acceleration (PGA) as shown in Table 5-1 (Reference 7). As described in Reference 8, a soil-structure interaction analysis was performed and new ISRS were developed for the IPEEE RLE. For comparison purposes, Figure 5-1 includes the Hatch IPEEE RLE, the Hatch Unit 1 DBE, the Hatch Unit 2 DBE, and the Hatch GMRS. Above 1Hz, the Hatch Units 1 and 2 IPEEE RLE spectrum is at least two times or larger than the Hatch Unit 1 DBE and the Hatch Unit 2 DBE, and is about twice the HatchGMRS.

To facilitate an early start (prior to obtaining the GMRS) and timely completion of the ESEP, the IPEEE RLE was used as the ESEP review level ground motion (RLGM) for most of the equipment in Plant Hatch Units 1 and 2. Only the surface-mounted condensate storage tanks (CSTs), which did not require ISRS, were evaluated to the GMRS.

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~u I II i

0.4 +---------,--1-,-+-~-1----i---i---i--~~---"~-~~--'-'-t-1-+1--H I I II U1 0.2 -l---..----A~~L~~~~~-...~...,.__::~;;::---...:_~-W--W II 0.1 1 10 100 Frequency (Hz)

Figure 5-1. Hatch IPEEE RLE Compared to the Unit 1 and Unit 2 DBEs and the GMRS Table 5-1. Plant Hatch IPEEE RLE Frequency (Hz) Spectra l Acceleration (g) 100 0.3 33 0.3 20 0.38 12.5 0.45 10 0.54 8 0.637 2 0.637 1 0.3 0.5 0. 15 MPR-4121 15 Re vision 0

5.2 METHOD TO ESTIMATE IN-STRUCTURE RESPONSE SPECTRUM (ISRS)

For structure-mounted equipment, the ESEP used the IPEEE RLE in-structure response spectra (ISRS). As stated in Section 5.1, the IPEEE ISRS are based on ground motion equal to or larger than twice the Hatch Unit 1 and Hatch Unit 2 DBEs.

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6 Seismic Margin Evaluation Approach The objective of the ESEP is to demonstrate that the ESEL items have sufficient seismic capacity to meet or exceed the seismic demand associated with the RLGM. Section 5 of Reference 2 provides guidance for characterizing the seismic capacity by determining a high confidence of low probability of failure (HCLPF) using either the Seismic Margin Assessment (SMA) methodology ofEPRI NP-6041-SL (Reference 10) or the fragility analysis methodology ofEPRI 1R-103959 (Reference 12). The Plant Hatch ESEP used the EPRINP-6041-SL SMA approach, consistent with the earlier combined A-46/IPEEE Program.

The HCLPF capacity is based on the weakest or most seismically limiting attribute of the equipment (structural, anchorage, or functional). The HCLPF evaluation considers the dynamic response of the equipment, but the HCLPF value is expressed in terms of a peak ground acceleration (PGA) to provide a common point of reference relative to the RLGM. Per Reference 2, ESEL items have sufficient seismic capacity if the HCLPF capacity is equal to or greater than the RLGM PGA.

6.1

SUMMARY

OF METHODOLOGIES USED Seismic Margin Assessments (SMAs) were performed for Plant Hatch Units 1 and 2 in the early 1990s and are documented in References 8 and 9. Those SMAs were performed as part of the combined A-46/IPEEE program at Plant Hatch and included many of the items on the ESEL. As part of the ESEP, the Seismic Review Team (SRT) evaluated each accessible item on the ESEL for seismic capacity, anchorage, and relay functionality (when a FLEX methodology relay was identified in the ESEL). (Inaccessible items are discussed in Section 7.1.) The ESEP walk.downs and evaluations were documented in Screening and Evaluation Work Sheets (SEWS), which include checklists that were developed from Appendix F of EPRI NP-6041-SL (Reference 10).

Each member of the SRT was trained as a SQUG Seismic Capability Engineer in accordance with the Generic Implementation Procedure (GIP) and trained in the use ofEPRI NP-6041-SL.

Selected team members also took the EPRI HCLPF course, which was developed for the ESEP implementation and is based on EPRI NP-6041-SL.

6.2 HCLPF SCREENING PROCESS ESEL items were evaluated for the Hatch IPEEE RLE, which is a median NUREG/CR-0098 type ground response spectrum anchored to 0.3g PGA, as shown in Figure 5-1. The only exception to this approach was used for the CSTs, as described below. The 5 percent damped Peak Spectral Acceleration of the Hatch IPEEE RLE allowed the use of the first column (<0.8g PSA) ofReference 10 Table 2-4 "Summary ofEquipment and Subsystems Screening Criteria for Seismic Margin Evaluation" in establishing HCLPFs greater than or equal to the RLE for ESEL MPR-4121 17 RevisionO

items. Anchorage evaluations were performed using the in-structure response spectra developed for the A-46/IPEEE program's RLE (shown in Figure 5-1).

For the CSTs, the HCLPFs were established using the rigorous methodology of Reference 10 Appendix H "Flat-Bottom Vertical Fluid Storage Tanks" and additional information provided during the EPRI HCLPF course (Reference 11 ). The review level earthquake for the CST HCLPF evaluations was the GMRS.

6.3 SEISMIC WALKDOWN APPROACH 6.3.1 Walkdown Approach ESEP walkdowns were performed in accordance with the criteria provided in Section 5 of Reference 2, which refers to Reference 10 for the Seismic Margin Assessment process. Pages 2-26 through 2-30 ofReference 10 describe the seismic walkdown guidance, including the following key points.

"The SRT [Seismic Review Team] should "walk by" 100% ofall components which are reasonably accessible and in non-radioactive or low radioactive environments. Seismic capability assessment ofcomponents which are inaccessible, in high-radioactive environments, or possibly within contaminated containment, will have to rely more on alternate means such as photographic inspection, more reliance on seismic reanalysis, and possibly, smaller inspection teams and more hurried inspections. A 100% "walk by" does not mean complete inspection ofeach component, nor does it mean requiring an electrician or other technician to de-energize and open cabinets or panels for detailed inspection ofall components. This walkdown is not intended to be a QA or QC review or a review ofthe adequacy ofthe component at the SSE level.

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

The walkdown procedure should be performed in an ad hoc manner. For each class ofcomponents the SRT should look closely at the first items and compare the field configurations with the construction drawings and/or specifications. Ifa one-to-one correspondence is found, then subsequent items do not have to be inspected in as great a detail. Ultimately the walkdown becomes a "walk by" ofthe component class as the SRT becomes MPR-4121 18 RevisionO

confident that the construction pattern is typical. This procedure for inspection should be repeated for each component class; although, during the actual walkdown the SRT may be inspecting several classes ofcomponents in parallel. Ifserious exceptions to the drawings or questionable construction practices are found then the system or component class must be inspected in closer detail until the systematic deficiency is defined.

The 100% "walk by" is to look for outliers, lack ofsimilarity, anchorage which is different from that shown on drawings or prescribed in criteria for that component, potential Sf [Seismic Interaction 1] problems, situations that are at odds with the team members 'past experience, and any other areas of serious seismic concern. Ifany such concerns surface, then the limited sample size of one component ofeach type for thorough inspection will have to be increased. The increase in sample size which should be inspected will depend upon the number ofoutliers and different anchorages, etc., which are observed. It is up to the SRT to ultimately select the sample size since they are the ones who are responsible for the seismic adequacy ofall elements which they screen from the margin review. Appendix D gives guidance for sampling selection. "

6.3.2 Application of Previous Walkdown Information Many ESEL items were previously walked down during the Plant Hatch A-46/IPEEE program using an IPEEE RLE that was equal to or greater than twice the DBEs. Consistent with the guidance in References 2 and 10, the A-46/IPEEE documentation for some electrical items was used to eliminate the need for electrical bus outages and minimize the risk of tripping the plant by not opening some energized electrical equipment that had been opened during the A-46/

IPEEE program.

Specifically, some ESEL items evaluated during the A-46/IPEEE program and shown to have a seismic capacity greater than or equal to the IPEEE RLE were evaluated but not opened to view anchorage. The ESEP walkdowns were performed to confirm consistency of these items with their A-46/IPEEE condition and address seismic capacity questions that could be answered without opening the equipment. Based on this information, which included documentation from the A-46/IPEEE SEWS, NTTF 2.3 seismic information, drawings, and calculations, the SRTs were able to evaluate the equipment capacity and anchorage without electrical bus outages or risk of tripping the plant by opening these items.

Previous walkdown information was also used for evaluation of inaccessible equipment, as discussed in Section 7.1.

1 EPRI 3002000704 (Reference 2) page 5-4 limits the ESEP seismic interaction reviews to "nearby block walls" and "piping attached to tanks" which are reviewed "to address the possibility of failures due to differential displacements." Other potential seismic interaction evaluations are "deferred to the full seismic risk evaluations performed in accordance with EPRI1025287 (Reference 6)."

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6.3.3 Significant Walkdown Findings Consistent with guidance from Reference 10, no significant seismic issues were identified at Plant Hatch during the final ESEP seismic walkdowns.

During initial ESEP seismic walkdowns, one significant seismic issue was identified:

• Anchorage for the nitrogen ambient vaporizer for each unit (1 T48-B004 and 2T48-B002) was degraded at the time of the initial walkdown and condition reports (CRs) were written to resolve the problem. These components were re-evaluated after repairs were made and the HCLPFs for the anchorages now meet or exceed the Hatch IPEEE RLE.

Smaller issues identified during the initial walkdowns (e.g., corrosion on anchor bolts for the Unit 1 outside nitrogen storage tank (1 T48-A001)) were entered as condition reports, resolved, and then re-evaluated to confirm that the components have HCLPFs that meet or exceed the Hatch IPEEE RLE.

Some block walls were identified in the proximity ofESEL equipment. During the A-46/IPEEE combined program, these block walls were assessed for their structural adequacy to withstand the seismic loads resulting from the Hatch IPEEE RLE.

6.4 HCLPF CALCULATION PROCESS Consistent with the Reference 10 deterministic/SMA methodology, the Plant Hatch ESEP acceptance criteria were that the equipment's structural/functional capacity, anchorage capacity, and relay functional capacity (when required) exceeded the seismic demand of the Hatch IPEEE RLE. Therefore, when these criteria were met, the HCLPF was defmed as being at least as high as the IPEEE RLE (0.3 g PGA), and calculation of specific HCLPF values in excess of 0.3 g PGA was not warranted. Specific HCLPF values were calculated for the CSTs so that both the tank capacities (e.g., shell failure modes) and anchorage capacities (e.g., cast-in-place L-bolts and anchor chairs) could be evaluated using the CDFM methodology in Appendix H of Reference 10 and additional information provided during the EPRI HCLPF course (Reference 11 ). The CSTs were evaluated using the GMRS instead of the IPEEE RLE.

6.5 FUNCTIONAL EVALUATION OF RELAYS Relays in four cabinets and three motor control centers (total for both units) required functional evaluations. Each relay was evaluated using the SMA relay evaluation criteria in Section 3 of Reference 10.

Seismic qualification test-based capacities were available for these specific relays in Plant Hatch documentation. For the twelve relays contained in four cabinets, capacity to demand evaluations were performed using the Plant Hatch relay seismic capacities and the IPEEE RLE ISRS scaled with the Reference 10 in-cabinet amplification factors. The four relays contained in the three MCCs were qualified during dynamic testing ofthe MCCs; therefore, the in-cabinet amplification was included within the testing. In each case, the capacity exceeded the demand.

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The ESEP relay functional evaluations were documented in the SEWS packages for these four cabinets and three motor control centers.

6.6 TABULATED ESEL HCLPF VALUES (INCLUDING KEY FAILURE MODES)

Tabulated ESEL HCLPF values are provided in Attachment A for Unit 1 and in Attachment B for Unit 2. The following notes apply to the information in the tables.

• Items which screened out of an explicit functional capacity analysis using EPRI NP-6041-SL (Reference 10) Table 2-4 have a HCLPF greater than or equal to the RLGM; therefore, the HCLPF is shown as "2:RLGM" in Tables A-1 and B-1. This is consistent with the SMA methodology of not calculating an explicit HCLPF capacity if the criteria for functional capacity (e.g., EPRI NP-6041-SL Table 2-4) are met and instead providing results as meeting or exceeding the seismic input level selected as the RLGM.

• It is unknown whether anchorage is the controlling failure mode for items that were screened for their functional capacity because the functional capacity may or may not be higher than the anchorage capacity. The one exception to this is that large, flat-bottom vertical tanks (e.g., the Condensate Storage Tanks (CSTs)) were evaluated using a methodology that includes all failure modes (i.e., anchorage failure modes and tank shell failure modes). The HCLPF values for these tanks are reported in Tables A-1 and B-1.

• Equipment containing FLEX Methodology ("FM") relays was assessed for relay functional capacity as described in Section 6.5 of this report. Because it is not known whether the capacity of the equipment containing the relay, the equipment's anchorage, or the relay's capacity is the controlling HCLPF, the HCLPF is shown as "2:RLGM" in Tables A-1 and B-1, and the Notes/Comments" column identifies the presence ofFM relay(s).

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7 Inaccessible Items 7.1 IDENTIFICATION OF ESEL ITEMS INACCESSIBLE FOR WALKDOWN The Plant Hatch ESELs contain about 70 items (total for both units) that are located in either the Drywells or Locked High Radiation Areas. In order to avoid dose (i.e., maintaining radiation exposure ALARA) and to reduce impact on refueling outages scheduled in 2015 and 2016, these ESEL items were evaluated to determine whether a walkdown was necessary. The inaccessible/high dose equipment includes the following classes:

• Accumulators (for the SRVs)

• Air-Operated Valves (SRVs)

• MOVs

• Temperature Elements

• Junction Boxes

• Pneumatic System Filters and PCV (Unit 2 only)

Appendix D of Reference 10 provides information regarding "Sampling." Specifically, on page D-1, "sampling is technically valid for identical or similar components if there is evidence that the components are manufactured and installed in a consistent manner.... In some instances access is severely limited by radioactive environments and limited sampling is the only practical method of conducting a walkdown."

Much of the inaccessible/high dose equipment was previously evaluated during the A-46/IPEEE program. Although 6 of the 18 SRV accumulators on the ESEL were not previously evaluated for the Plant Hatch IPEEE RLE, sampling is a practical approach for concluding that they also have HCLPFs that meet or exceed the ESEP RLGM.

Like the SRV accumulators, most of the SRVs were also evaluated during the A-46/IPEEE program, and were found to meet SMA criteria for the IPEEE RLE. The SRVs, however, have been replaced since the A-46/IPEEE, or they are scheduled to be replaced in the next refueling outage (RFO). The replacement valves should be at least as robust as the SRVs that were evaluated during the A-46/IPEEE program. Additionally, in accordance with Reference 10, Table 2-4, active valves screen out from further SMA evaluations at the five percent-damped peak spectral acceleration for the Hatch IPEEE RLE (<0.8g). Therefore, additional ESEP walkdowns and the associated dose are not warranted.

A similar argument is made for the 8 MOVs (total for both units), where half of the MOVs were explicitly included in the A-46/IPEEE program. In accordance with Reference 10, Table 2-4, MPR-4121 22 RevisionO

active valves screen out from further SMA evaluations at the five percent-damped peak spectral acceleration for the Hatch IPEEE RLE (<0.8g). Therefore, additional ESEP walkdowns and the associated dose are not warranted.

The temperature elements in the Drywell are considered to be represented by the ten temperature elements that were walked down (total for both units), and no seismic issues were identified; therefore, the inaccessible temperature elements do not merit specific walkdowns.

Junction boxes were not part of the A-46/IPEEE program, but dozens have been walked down during the ESEP, and no seismic issues have been identified; therefore, junction boxes in the drywell do not merit walkdowns.

Finally, there are three inaccessible/high dose devices related to the Unit 2 Drywell pneumatic system: two filters and one pressure control valve (PCV). Filters are passive devices and considered seismically rugged, as are typical PCVs. The Unit 1 pneumatic system filters and the PCV are in a Reactor Building diagonal (outside the drywell) and were walked down; no seismic issues were identified for these small passive devices. None of these devices merit a Drywell entry and the dose associated with performing walkdowns for the ESEP.

7.2 PLANNED WALKDOWN/EVALUATION SCHEDULE/CLOSE OUT Walkdowns have been completed for installed accessible items on the ESELs. Section 7.1 discusses the disposition for inaccessible items. ESEL items that have not been installed or for which FLEX modifications have not been completed as of the time of this report will be evaluated after installation or modification per the SMA methodology outlined in Reference 10.

See Section 8.4 and Tables A-1 and B-1 for details.

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8 ESEP Conclusions and Results 8.1 SUPPORTING INFORMATION Plant Hatch has performed the ESEP as in interim action in response to the NRC's 50.54(t) letter (Reference 1). It was performed using the methodologies in the NRC endorsed guidance in EPRI 3002000704 (Reference 2).

The ESEP provides an important demonstration of seismic margin and expedites plant safety enhancements through evaluations and potential near-term modifications of plant equipment that can be relied upon to protect the reactor core following beyond design basis seismic events.

The ESEP is part of the overall Plant Hatch response to NRC's 50.54(t) letter (Reference 1). On March 12,2014, NEI submitted to the NRC results of a study (Reference 13) of seismic core damage risk estimates based on updated seismic hazard information as it applies to operating nuclear reactors in the Central and Eastern United States (CEUS). The study concluded that site-specific seismic hazards show that there has not been an overall increase in seismic risk for the fleet ofU.S. plants based on the re-evaluated hazard. As such, the "current seismic design of operating reactors continues to provide a safety margin to withstand potential earthquakes exceeding the seismic design basis."

The NRC's May 9, 2014 NTIF 2.1 Screening and Prioritization letter (Reference 14) concluded that the "fleetwide seismic risk estimates are consistent with the approach and results used in the GI-199 safety/risk assessment." The letter also stated that "As a result, the staffhas confirmed that the conclusions reached in GI-199 safety/risk assessment remain valid and that the plants can continue to operate while additional evaluations are conducted."

An assessment of the change in seismic risk for Plant Hatch was included in the fleet risk evaluation submitted in the March 12, 2014 NEI letter (Reference 13); therefore, the conclusions in the NRC's May 9letter (Reference 14) also apply to Plant Hatch.

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

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

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• Safety factors applied in design calculations

• Damping values used in dynamic analysis of SSCs

• Bounding synthetic time histories for in-structure response spectra calculations

• Broadening criteria for in-structure response spectra

• Response spectra enveloping criteria typically used in SSC analysis and testing applications

• Response spectra based frequency domain analysis rather than explicit time history based time domain analysis

• Bounding requirements in codes and standards

• Use ofminimum strength requirements of structural components (concrete and steel)

• Bounding testing requirements, and

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

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

8.2 IDENTIFICATION OF PLANNED MODIFICATIONS No modifications have been identified as necessary to meet ESEP acceptance criteria.

8.3 MODIFICATION IMPLEMENTATION SCHEDULE No modifications have been identified for the items that have been evaluated. SNC intends to comply with the ESEP schedule (Attachment 2 of Reference 15) for any modifications determined to be necessary for items to be walked down as identified in Sections 7.2 and 8.4.

8.4

SUMMARY

OF REGULATORY COMMITMENTS Please refer to the Table of Regulatory Commitments that will accompany this report.

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9 References

1. NRC Letter to All Power Reactor Licensees et al., "Request for Information Pursuant to Title 10 ofthe Code ofFederal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3 of the Near-Term Task Force Review oflnsights from the Fukushima Dai-ichi Accident," dated March 12,2012 [ADAMS Accession Number ML12053A340].

2. EPRI Report 3002000704, "Seismic Evaluation Guidance: Augmented Approach for the Resolution ofFukushima Near-Term Task Force Recommendation 2.1- Seismic," Electric Power Research Institute, May 2013.

3. SNC Nuclear Letter NL-14-0593, "Edwin I. Hatch Nuclear Plant Units 1 and 2 Third Six-Month Status Report of the Implementation of the Requirements of the Commission Order with Regard to Mitigation Strategies for Beyond-Design-Basis External Events (EA 049)," dated August 26,2014.

4. ENERCON Engineering Report SNCH106-PR-001, Rev. 3, "Equipment Selection for the Expedited Seismic Evaluation Process for Southern Nuclear Operating Company, Inc.,

Hatch Nuclear Plant Unit No. 1."

5. ENERCON Engineering Report SNCH106-PR-002, Rev. 3, "Equipment Selection for the Expedited Seismic Evaluation Process for Southern Nuclear Operating Company, Inc.,

Hatch Nuclear Plant Unit No. 2."

6. EPRI Report 1025287, "Seismic Evaluation Guidance: Screening, Prioritization and Implementation Details (SPID) for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1: Seismic," Electric Power Research Institute, February 2013.

7. SNC Nuclear Letter NL-14-0343, "Edwin I. Hatch Nuclear Plant Units 1 and 2 Seismic Hazard and Screening Report for CEUS Sites," dated March 31,2014.

8. EPRI Report NP-7217. "Seismic Margin Assessment of the Edwin I. Hatch Nuclear Plant, Unit 1," Electric Power Research Institute, June 1991.

9. "Individual Plant Examination for External Events, Edwin I. Hatch Nuclear Plant, Units 1 and 2" (Response to Generic Letter 88-20, Supplement 4).

10. EPRI NP-6041-SL, "A Methodology for Assessment of Nuclear Power Plant Seismic Margin, Revision 1,** Electric Power Research Institute, August 1991.

11. Hardy, Greg and Dr. Robert Kennedy, "High Confidence of a Low Probability of Failure (HCLPF) Calculation Training," EPRI, (August 2013).

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12. EPRI TR-1 03959, "Methodology for Developing Seismic Fragilities," Electric Power Research Institute, 1999.

13. NEI (A. Pietrangelo) letter to NRC (E. Leeds) dated March 12, 2014, "Seismic Risk Evaluations for Plants in the Central and Eastern United States."

14. NRC (E. Leeds) letter dated May 9, 2014, "Screening and Prioritization Results Regarding Information Pursuant to Title 10 ofthe Code of Federal Regulations 50.54(f) Regarding Seismic Hazard Re-Evaluations for Recommendation 2.1 of the Near-Term Task Force Review oflnsights from the Fukushima Dai-ichi Accident."

15. NEI (A. Pietrangelo) letter to NRC (D. Skeen) dated April9, 2013, "Proposed Path Forward for NTTF Recommendation 2.1: Seismic Reevaluations."

16. Dr. Robert Kennedy letter to Southern Company Services (D. Moore) dated August 13, 1993, "Re: Hatch Condensate Water Tank."

17. MPR Calculation No. 0380-0050-01, "Hatch Unit 2 Condensate Storage Tank,"

Revision 0, December 15, 2014.

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Attachment A: Plant Hatch Unit 1 ESEL Table A-1. Plant Hatch Unit 1 ESEL Items and HCLPF Results Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Inaccessible/High 1821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A0038 7.1 Inaccessible/High 1821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003D 7.1 Inaccessible/High 1821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003E 7.1 Inaccessible/High 1821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003F 7.1 Inaccessible/High 1821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003G 7.1 Inaccessible/High 1821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003H 7.1 Inaccessible/High 1821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003J 7.1 Inaccessible/High 1821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003K 7.1 Inaccessible/High 1821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003L 7.1 MPR-4121 A-1 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Inaccessible/High 1B21-MSL "A" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013B 7.1 Inaccessible/High 1B21-MSL "B" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013D 7.1 Inaccessible/High 1B21-MSL "B" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013E 7.1 Inaccessible/High 1B21-MSL "C' RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013F 7.1 Inaccessible/High 1B21-MSL "C" RPV SRV (LLSL) Closed Closed/Open N/A Dose; See Section F013G 7.1 Inaccessible/High 1B21-MSL "D" RPV SRV (LLSL) Closed Closed/Open N/A Dose; See Section F013H 7.1 Inaccessible/High 1B21-MSL "D" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013J 7.1 Inaccessible/High 1B21-MSL "B" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013K 7.1 Inaccessible/High 1B21-MSL 'C' RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013L 7.1 1B21- RPV Levels 2 & 1 LT- Div II -

Operating Operating ~ RLGM N091B Batt 1B21- LPCI RX Water Level MTU LIS Operating Operating ~RLGM N691B - Div II- Batt 1B21- RPV Level (Hot Leg) Ll - Div II -

Operating Operating ~RLGM R604B Batt MPR-4121 A-2 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 1C32- FWC RX Pressure Transmitter Operating Operating ~RLGM KGSSC C - Div II - Batt 1C32-RX WTR LVL RFP TRIP C Operating Operating ~RLGM K902 1C32- FWC RX Water Level PT- Div Operating Operating ~RLGM NOOSC II- Batt 1C32-FWC RX PI - Div II - Batt Operating Operating ~ RLGM RGOSC 1C82- REMOTE SHUTDOWN PANEL-Available Available ~RLGM POOl ESl 1C82-REMOTE SHUTDOWN PANEL Available Available ~RLGM P002 lEll-RHR HEAT EXCHANGER Available Available ~RLGM BOOlA lEll- RHR HX OUTLT 16" GATE Open Closed ~ RLGM F003A MOV Inaccessible/High lEll- Shutdown Cooling Outboard Closed Closed N/A Dose; See Section FOOS Iso 7.1 Inaccessible/High lEll- Inboard Injection Gate MOV Closed Open N/A Dose; See Section FOlSA (RHR lnbd lnj Vlv) 7.1 Inaccessible/High lEll- Outboard Injection Gate MOV Open Throttled N/A Dose; See Section F017A (RHR Outbd lnj Vlv) 7.1 lEll- RHR HX Bypass Globe MOV Open Closed ~RLGM F048A (Hx Bypass Vlv) lEll- HX SW FLOW CONTROLLER Closed Closed ~RLGM F068A MOV lEll- RHRSW TO RHR CROSSTIE Closed Closed/Open ~RLGM F073A MOV MPR-4121 A-3 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 1E11- RHRSW TO RHR CROSSTIE Closed Closed/Open ~RLGM F07SA MOV 1E11-RHR HX Discharge TE- Div II Operating Operating ~RLGM N027B 1E51- RCIC BAROMETRIC Standby Operating ~ RLGM AOOl CONDENSER 1E51-RCIC LUBE OIL COOLER Standby Operating ~RLGM BOOl 1E51- RCIC REACTOR MAKEUP Standby Operating ~RLGM COOl PUMP 1ES1-RCIC TURBINE Standby Operating <!:RLGM C002 Inaccessible/High 1E51-STEAM SUPPLY ISO GATE VLV Open Open N/A Dose; See Section F008 7.1 1E51- Pump Suction 6" Gate MOV Open Open/Closed ~RLGM F010 {CST Suction Valve) 1E51- RCIC PUMP DISCHARGE GATE Open Open <!:RLGM F012 MOV 1ES1- Pump Disch 4" Gate MOV Closed Open ~ RLGM F013 {Pump Discharge Valve) 1E51-RCIC COOLING WATER PCV Open Operating <!:RLGM F015 lESl- Min Flow 2" Bypass MOV Closed Closed/Open <!:RLGM F019 {RCIC Min-Flow Valve) 1E51- PUMP SUCTION GATE VALVE Closed Closed/Open <!:RLGM F029 {Suppression Pool Suction) 1E51- PUMP SUCTION GATE VALVE Closed Closed/Open ~RLGM F031 {Suppression Pool Suction)

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Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results lESl- RCIC BAROMETRIC Standby Standby ~RLGM F033 CONDENSER RELIEF VALVE lESl- RCIC STEAM SUPPLY GLB Closed Open ~RLGM F045 MOV COOLING WATER GLOBE lESl-VALVE MOV (From Pump Closed Open ~RLGM F046 Discharge)

Steam Supply 3" Governing lESl-Gate HOV Open Operating ~ RLGM F523 (RCIC Governor Valve)

Steam Supply 3" Trip Throttle lESl-MOV (RCIC Open Open ~RLGM F524 Trip & Throttle Valve) lESl-RCIC CST LO LS - Div I - Batt Operating Operating ~RLGM N060 lESl-RCIC CST LO LS - Div I - Batt Operating Operating ~RLGM N061 lHll-RX & CTMT CLG & ISO PNL Available Available ~ RLGM P601 lHll-RWCU & RECIRC PNL Available Available ~RLGM P602 lHll-Reac Control BN BD - Panel Available Available ~RLGM P603 lHll- CLS lE Analog Signal Available Available ~RLGM P605B Converter/IS Panel lHll-FW/Recirc INST Panel Available Available ~RLGM P612 Includes FM lHll-RCIC RELAY VB Available Available ~RLGM Relays; See P621 Section 6.5 MPR-4121 RevisionO A-5

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 1H11-Inboard lso Valve Vert Panel Available Available  ;:::RLGM P622 Includes FM 1H11- Outboard lso Valve Vert Available Available  ;:::RLGM Relays; See P623 Panel Section 6.5 1H11-AUTO DEPRESS RELAY VB Available Available  ;:::RLGM P628 1H11- Gas Treat Vent Vert BD -

Available Available  ;:::RLGM P654 Panel 1H11- BEARING TEMP & BAT MON Available Available  ;:::RLGM P655 VB 1H11- Analog Signal Converter Available Available  ;:::RLGM P691B Panel 1H11-ANAL/VENT & LEAK DET PNL Available Available  ;:::RLGM P700 1H11-ATTS ECCS MCR Panel Available Available  ;:::RLGM P925 1H11-ATTS ECCS MCR Panel Available Available  ;:::RLGM P926 1H11- ATTS ECCS Trip Unit Cabinet-Available Available  ;:::RLGM P927 Panel 1H11- ATTS ECCS Trip Unit Cabinet-Available Available  ;:::RLGM P928 Panel 1H21-RV LEVEL/PRESS LOC PNL A Available Available  ;:::RLGM P004 1H21-RCIC SYSTEM ESl PANEL Available Available  ;:::RLGM POSl 1H21- SHUTDOWN INSTRUMENT Available Available  ;:::RLGM P173 PANEL MPR-4121 A-6 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 1H21-RX VESSEL INST RACK Available Available <!:RLGM P405A Screened to GMRS 1Pll-Condensate Storage Tank Available Available 0.15g instead of IPEEE A100 RLE; Reference 16 Not Yet Installed; 1P52- AIR ACC (BKUP AIR Available Available N/A See Sections 7.2 &

A027A ACCUMULATOR TANK A) 8.4 Not Yet Installed; 1P52- AIR ACC (BKUP AIR Available Available N/A See Sections 7.2 &

A027B ACCUMULATOR TANK B) 8.4 Relief Valve N2 Cylinder Not Yet Installed; 1P52-Supply Manifold Standby Standby N/A See Sections 7.2 &

F1312 Overpressure Protection 8.4 1P70-D/W N2 SYSTEM RECEIVER Available Available <!:RLGM A001 1P70-100 MICRON NOM FILTER Available Available <!:RLGM D008A 1P70-5 MICRON NOM FILTER Available Available <!:RLGM D009A 1P70- D/W PNEUMATIC N2 SPLY Closed Open <!:RLGM F001A AOV 1P70- D/W PNEUMATIC HEADER Operating Operating <!:RLGM F103A PCV 1R22-125/250VDC Switchgear 1A Energized Energized <!:RLGM S016 1R22-125/250VDC Switchgear 1B Energized Energized <!:RLGM S017 1R23- 600VAC Bus 1C -

Energized Energized <!:RLGM S003 Switchgear/XFM R MPR-4121 A-7 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 1R23- 600VAC Bus 1D-Energized Energized ~RLGM S004 Switchgear/XFMR Includes FM 1R24-250VDC MCC 1A Energized Energized ~RLGM Relays; See S021 Section 6.5 Includes FM 1R24-250VDC MCC 1A-1 Energized Energized ~RLGM Relays; See S021A Section 6.5 1R24-250VDC MCC 1B Energized De-Energized ~RLGM S022 1R25- 125VDC Distribution Cabinet Energized Energized ~RLGM S001 1A 1R25- 125VDC Distribution Cabinet Energized Energized ~ RLGM S002 1B 1R25- 120/208VAC Instrument Bus Available Available ~RLGM S064 1A- Div I 1R25- 120/208VAC Instrument Bus Available Available ~RLGM S065 1B- Div II Not Yet Installed; 1R25- 120VAC CRITICAL Energized Energized N/A See Sections 7.2 &

S066 INSTRUMENT CABINET 1A 8.4 Not Yet Installed; 1R25- 120VAC CRITICAL Energized Energized N/A See Sections 7.2 &

S067 INSTRUMENT CABINET 1B 8.4 1R25- Emergency Lighting Cabinet -

Energized Energized ~ RLGM S069 Div II 1R25- Emergency Lighting Cabinet -

Energized Energized ~RLGM S094 Div II 1R25- 125VDC Distribution Cabinet Energized Energized ~RLGM S106 1E MPR-4121 A-8 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 1R26- Standby/ Standby/

12SVDC THROWOVER SW 1A ~RLGM M031A Closed Closed 1R26- Standby/ Standby/

12SVDC THROWOVER SW 1B ~RLGM M031B Closed Closed 1R26- Standby/ Standby/

12SVDC THROWOVER SW 1C ~RLGM M031C Closed Closed 1R26- Standby/ Standby/

125VDC THROWOVER SW 1D ~RLGM M031D Closed Closed Not Yet Installed; 1R26- FLEX FUSED DISCONNECT Standby Standby N/A See Sections 7.2 &

M132 SWITCH 1A 8.4 Not Yet Installed; 1R26- FLEX FUSED DISCONNECT Standby Standby N/A See Sections 7.2 &

M133 SWITCH 1B 8.4 Not Yet Installed; 1R26-FLEX TRANSFER SWITCH 1A Normal Normal N/A See Sections 7.2 &

M136 8.4 Not Yet Installed; 1R26-FLEX TRANSFER SWITCH 1B Normal Normal N/A See Sections 7.2 &

M137 8.4 Not Yet Installed; 1R26-FLEX TRANSFER SWITCH 1D Normal Normal N/A See Sections 7.2 &

M139 8.4 Not Yet Installed; 1R26-FLEX TRANSFER SWITCH 1E Normal Normal N/A See Sections 7.2 &

M140 8.4 1R42- 125/2SOVDC Station Battery Energized Energized ~ RLGM S001A 1A 1R42- 125/2SOVDC Station Battery Energized Energized ~RLGM S001B 1B MPR-4121 A-9 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results FLEX Mod Not Yet 1R42-Battery Charger lA- Div I Energized Energized N/A Complete; See S026 Sections 7.2 & 8.4 FLEX Mod Not Yet 1R42-Battery Charger lB - Div I Energized Energized N/A Complete; See S027 Sections 7.2 & 8.4 1R42-Battery Charger 10 - Div II Energized Energized O!:RLGM S029 1R42-Battery Charger lE - Div II Energized Energized ~ RLGM S030 Not Yet Installed; 1R44- 250VDC/120VACINVERTER Energized Energized N/A See Sections 7.2 &

S006 lA 8.4 Not Yet Installed; 1R44- 250VDC/120VAC INVERTER Energized Energized N/A See Sections 7.2 &

S007 lB 8.4 1T47-SIGNAL CONVERTER R/V Operating Operating ~RLGM K600 1T47-NOOlA,B SIGNAL CONV R/V Operating Operating ~RLGM K602 1T47-NOOlM, N003 SIG CONV R/V Operating Operating ~RLGM K603 1T47-NOOS, N007 SIG CONV R/V Operating Operating ~ RLGM K604 1T47-NOlO SIGNAL CONV R/V Operating Operating ~ RLGM K605 Inaccessible/High 1T47-B009A Inlet Air TE- Div II Operating Operating N/A Dose; See Section NOOlA 7.1 MPR-4121 A-10 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Inaccessible/High 1T47-DW CLG Dome Area TE- Div II Operating Operating N/A Dose; See Section NOOlB 7.1 I

Inaccessible/High 1T47-B009A&B Inlet Air TE- Div II Operating Operating N/A Dose; See Section NOOlM 7.1 Inaccessible/High 1T47- DW CLG Midlevel Area TE-Operating Operating N/A Dose; See Section N003 Divll 7.1 Inaccessible/High 1T47- DW Lower Level Area TE- Div Operating Operating N/A Dose; See Section NOOS II 7.1 Inaccessible/High 1T47- DW Lower Level Area TE- Div Operating Operating N/A Dose; See Section N007 II 7.1 Inaccessible/High 1T47-Sacrificial Shield Top TE- Div II Operating Operating N/A Dose; See Section NOlO 7.1 1T47- DW CLG CRD/Torus Area TR -

Operating Operating 2: RLGM R612 Divll Repaired under 1T48- CAP and re-walked NITROGEN STORAGE TANK Available Available 2: RLGM AOOl down; See Section 6.3.3.

Repaired under 1T48- N2 TANK AMBIENT CAP and re-walked Available Available 2: RLGM 8004 VAPORIZER down; See Section 6.3.3.

1T48- 8004 DISCH LINE RELIEF Standby Standby 2: RLGM F072 VALVE 1T48- 8004 DISCHARGE PCV (N2 Operating Operating 2: RLGM F075 system)

MPR-4121 A-ll Revision 0

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 1T48-HCVS Vent Control AOV Closed Closed/Open  ::!:RLGM F082 1T48- HCVS Containment Isolation Closed Closed/Open  ::!:RLGM F318 AOV 1T48- HCVS Containment Isolation Closed Closed  ::!:RLGM F319 AOV 1T48- HCVS Containment Isolation Closed Closed  ::!:RLGM F320 AOV 1T48- HCVS Containment Isolation Closed Closed/Open  ::!:RLGM F326 AOV Not Yet Installed; 1T48- Relief Valve Argon Supply Standby Standby N/A See Sections 7.2 &

F408 Overpressure Protection 8.4 1T48-OW Pressure lnst IN- Oiv II Operating Operating  ::!:RLGM K608B 1T48- OW/Torus Pressure lnst IN-Operating Operating  ::!:RLGM K609B Oiv II 1T48-TORUS AIR TEMP RN Operating Operating  ::!:RLGM K621B 1T48-Torus Levellnst IN- Div II Operating Operating  ::!:RLGM K623B 1T48-Torus Midrange PT- Div II Operating Operating  ::!:RLGM N008B 1T48-Torus Water TE- Oiv II Operating Operating  ::!:RLGM N009B 1T48-Torus Water TE- Oiv II Operating Operating  ::!:RLGM N0090 1T48-Torus Air TE- Oiv II Operating Operating  ::!:RLGM N009F MPR-4121 A-12 Revision 0

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 1T48-Torus Air TE- Div II Operating Operating  :::RLGM N009H 1T48-DW Narrow Range PT- Div II Operating Operating  :::RLGM N020B 1T48- Narrow Range Torus LT- Div Operating Operating  :::RLGM N021B II 1T48-DW Midrange PT- Div II Operating Operating  :::RLGM N023B 1T48- DW and Torus Narrow Range Operating Operating  :::RLGM R607B L/PR- Div II 1T48- OW/Torus Midrange PR- Div Operating Operating  :::RLGM R609 II Not Yet Installed; 1X86- 600V FLEX Diesel Generator Standby Standby N/A See Sections 7.2 &

S003 (FLEX Connection Box 1A) 8.4 Not Yet Installed; 1X86- 600V FLEX Diesel Generator Standby Standby N/A See Sections 7.2 &

S004 (FLEX Connection Box 1B) 8.4 ESS JUNCTION BOX Available Available  :::RLGM J379 ESS JUNCTION BOX Available Available  :::RLGM J423 ESS JUNCTION BOX Available Available  :::RLGM J422 Inaccessible/High J614 JUNCTION BOX Available Available N/A Dose; See Section 7.1 Inaccessible/High J615 JUNCTION BOX Available Available N/A Dose; See Section 7.1 MPR-4121 A-13 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Inaccessible/High J617 JUNCTION BOX Available Available N/A Dose; See Section 7.1 Inaccessible/High J618 JUNCTION BOX Available Available N/A Dose; See Section 7.1 Inaccessible/High J619 JUNCTION BOX Available Available N/A Dose; See Section 7.1 Inaccessible/High J620 JUNCTION BOX Available Available N/A Dose; See Section 7.1 Inaccessible/High J621 JUNCTION BOX Available Available N/A Dose; See Section 7.1 Inaccessible/High J647 JUNCTION BOX Available Available N/A Dose; See Section 7.1 Inaccessible/High J648 JUNCTION BOX Available Available N/A Dose; See Section 7.1 TB1-TERMINATION BOX Available Available  ::!:RLGM 1529-7 MPR-4121 A-14 RevisionO

Attachment B: Plant Hatch Unit 2 ESEL Table B-1. Plant Hatch Unit 2 ESEL Items and HCLPF Results Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Inaccessible/High 2821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003A 7.1 Inaccessible/High 2821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A0038 7.1 Inaccessible/High 2821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003C 7.1 Inaccessible/High 2821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003E 7.1 Inaccessible/High 2821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003F 7.1 Inaccessible/High 2821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003H 7.1 Inaccessible/High 2821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003K 7.1 Inaccessible/High 2821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003L 7.1 Inaccessible/High 2821-SRV AIR ACCUMULATOR Available Available N/A Dose; See Section A003M 7.1 MPR-4121 B-1 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Inaccessible/High 2821-MSL "A" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013A 7.1 Inaccessible/High 2821-MSL "B" RPV SRV (LLSL) Closed Closed/Open N/A Dose; See Section F013B 7.1 Inaccessible/High 2821-MSL "C" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013C 7.1 Inaccessible/High 2821-MSL "A" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013E 7.1 Inaccessible/High 2821-MSL "B" RPV SRV (LLSL) Closed Closed/Open N/A Dose; See Section F013F 7.1 Inaccessible/High 2B21-MSL "D" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013H 7.1 Inaccessible/High 2821-MSL "B" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013K 7.1 Inaccessible/High 2821-MSL "B" RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013L 7.1 Inaccessible/High 2821-MSL 'C' RPV SRV (ADS) Closed Closed/Open N/A Dose; See Section F013M 7.1 2821- RPV Levels 2 & 1 LT- Div II Operating Operating ~RLGM N091B -Batt 2B21- LPCI RX Water Level MTU Operating Operating ~ RLGM N691B LIS - Div II - Batt 2821- RPV Level (Hot Leg) Ll - Div Operating Operating ~RLGM R604B II -Batt MPR-4121 B-2 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 2C32-RX WTR LVL RFP TRIP C Operating Operating  ::!:RLGM IN02 2C32- FWC RX Pressure Operating Operating  ::!:RLGM KGSSC Transmitter C- Div II - Batt 2C32- FWC RX Water Level PT -

Operating Operating  ::!:RLGM Noose Div II- Batt 2C32-FWC RX PI - Div II - Batt Operating Operating  ::!:RLGM RGOSC 2C82-REMOTE S/D PANEL Available Available  ::!:RLGM POOl 2E11-RHR HEAT EXCHANGER Available Available <!:RLGM BOOlA 2E11- RHR HX OUTLT 16" GATE Open Closed  ::!:RLGM F003A MOV Inaccessible/High 2E11- Shutdown Cooling Closed Closed N/A Dose; See Section F008 Outboard lso 7.1 Inaccessible/High 2E11- Inboard Injection Gate Closed Open N/A Dose; See Section FOlSA MOV (RHR lnbd lnj Vlv) 7.1 Inaccessible/High 2E11- Outboard Injection Gate Open Throttled N/A Dose; See Section F017A MOV (RHR Outbd lnj Vlv) 7.1 2E11- RHR HX Bypass Globe MOV Open Closed  ::!:RLGM F048A (Hx Bypass Vlv) 2E11- HX SW FLOW CONTROLLER Closed Closed  ::!:RLGM F068A MOV 2E11-RHRSW CROSSTIE VALVE Closed Closed/Open  ::!:RLGM F073A 2E11-RHRSW CROSSTIE VALVE Closed Closed/Open  ::!:RLGM F075A lviPR-4121 B-3 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 2E11-RHR HX Discharge TE- Div II Operating Operating ~ RLGM N027B 2E51- RCIC BAROMETRIC Standby Operating ~ RLGM A001 CONDENSER 2E51-RCIC LUBE OIL COOLER Standby Operating ~RLGM B001 2E51- RCIC REACTOR MAKEUP Standby Operating ~ RLGM COOl PUMP 2E51-RCIC TURBINE Standby Operating ~ RLGM C002 Inaccessible/High 2E51- STEAM SUPPLY ISO GATE Open Open N/A Dose; See Section F008 VLV 7.1 2E51- Pump Suction 6" Gate MOV Open Open/Closed ~ RLGM F010 (CST Suction Valve) 2E51- RCIC PUMP DISCHARGE Open Open ~RLGM F012 GATE MOV 2E51- Pump Disch 4" Gate MOV Closed Open ~ RLGM F013 (Pump Discharge Valve) 2E51-RCIC COOLING WATER PCV Open Operating ~ RLGM F015 Min Flow 2" Bypass MOV 2E51-

{RCIC Min-Flow Closed Closed/Open ~RLGM F019 Valve) 2E51- TEST THROTILE GLOBE Closed Closed ~RLGM F022 VALVE 2E51- PUMP SUCTION GATE Closed Closed/Open ~ RLGM F029 VALVE 2E51- PUMP SUCTION GATE Closed Closed/Open ~ RLGM F031 VALVE MPR-4121 B-4 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 2E51- RCIC BAROMETRIC Standby Standby :i::RLGM F033 CONDENSER RELIEF VALVE 2E51- RCIC STEAM SUPPLY GLB Closed Open :i::RLGM F045 MOV COOLING WATER GLOBE 2E51-VALVE MOV (RHR Suction Closed Open :i::RLGM F046 Valve)

Steam Supply 3" Governing 2E51-Gate HOV Open Operating :i::RLGM F523 (RCIC Governor Valve)

Steam Supply 3" Trip 2E51-Throttle MOV (RCIC Open Open :i::RLGM F524 Trip & Throttle Valve) 2E51-RCIC CST LO LS - Div I - Batt Operating Operating :i::RLGM N060 2E51-RCIC CST LO LS - Div I - Batt Operating Operating :i::RLGM N061 2Hll-RX & CTMT CLG & ISO PNL Available Available :i::RLGM P601 2Hll-RWCU & RECIRC PNL Available Available  ::::RLGM P602 2Hll-Reac Control BN BD - Panel Available Available :i::RLGM P603 2Hll- CLS lE Analog Signal Available Available :i::RLGM P605B Converter/IS Panel 2Hll-FW/Recirc INST Panel Available Available :i::RLGM P612 Includes FM 2Hll-RCIC RELAY VB Available Available :i::RLGM Relays; See P621 Section 6.5 MPR-4121 B-5 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 2Hll-INBD ISO VLV VERT PNL Available Available ~RLGM P622 Includes FM 2Hll- Outboard lso Valve Vert Available Available ~RLGM Relays; See P623 Panel Section 6.5 2Hll-AUTO DEPRESS RELAY VB Available Available ~RLGM P628 2Hll- TURB FDWTR & COND CON Available Available ~RLGM PGSO PNL 2Hll- Gas Treat Vent Vert BD -

Available Available ~ RLGM P654 Panel 2Hll- BEARING TEMP & BAT Available Available ~ RLGM PGSS MONVB 2Hll- STARTUP BOILER VERT Available Available ~RLGM P656 PANEL 2Hll- Analog Signal Converter Available Available ~RLGM P691B Panel 2Hll- ATTS ECCS Trip Unit Available Available ~RLGM P925 Cabinet - Panel 2Hll-ATTS ECCS MCR Panel Available Available ~RLGM P926 2Hll- ATTS ECCS Trip Unit Available Available ~RLGM P927 Cabinet - Panel 2Hll- ATTS ECCS Trip Unit Available Available ~RLGM P928 Cabinet - Panel 2H21-RV LEVEL/PRESS LOC PNL A Available Available ~RLGM P004 2H21-RCIC SYSTEM 2E51 PANEL Available Available ~ RLGM POSl MPR-4121 B-6 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 2H21-RCICTESTVALVE PI PANEL Available Available <!:RLGM P053 2H21- DG FUEL PMP&MOV CONT Available Available ~RLGM P255 PNL 2H21-RX VESSEL INST RACK Available Available <!:RLGM P40SA 2JE1891 JUNCTION BOX Available Available ~RLGM 2JE2712 JUNCTION BOX Available Available ~RLGM 2JE2798 JUNCTION BOX Available Available <!:RLGM Inaccessible/High 2JM7873 JUNCTION BOX Available Available N/A Dose; See Section 7.1 Screened to GMRS 2P11-Condensate Storage Tank Available Available 0.18g instead of IPEEE A001 RLE; Ref.17 Not Yet Installed; 2P52- BKUP AIR ACCUMULATOR Available Available N/A See Sections 7.2 &

A027A TANKA 8.4 Not Yet Installed; 2P52- BKUP AIR ACCUMULATOR Available Available N/A See Sections 7.2 &

A027B TANKB 8.4 Relief Valve N2 Cylinder Not Yet Installed; 2P52-Supply Manifold Standby Standby N/A See Sections 7.2 &

F1228 Overpressure Protection 8.4 Inaccessible/High 2P70-100 MICRON NOM FILTER Available Available N/A Dose; See Section D008A 7.1 Inaccessible/High 2P70-5 MICRON NOM FILTER Available Available N/A Dose; See Section D009A 7.1 MPR-4121 B-7 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Inaccessible/High 2P70- D/W PNEUMATIC HEADER Operating Operating N/A Dose; See Section F103A PCV 7.1 2R11- 600-120/208V LTG & PWR Energized Energized ~RLGM S004 TX 2R20M-FUSE BOX Available Available ~ RLGM POOl 2R22-125/250VDC Switchgear 2A Energized Energized ~RLGM S016 2R22-125/2SOVDC Switchgear 2B Energized Energized ~RLGM S017 2R23- 600VAC Bus 2C-Energized Energized ~ RLGM S003 Switchgear/XFMR 2R23- 600VAC Bus 2D-Energized Energized ~ RLGM S004 Switchgear/XFMR Includes FM 2R24-250VDC MCC 2A Energized Energized ~RLGM Relays; See S021 Section 6.5 2R24-250VDC MCC 2B Energized De-Energized ~RLGM S022 lA lA Energized; Energized; 2R24- D/G BLDG 600/208V MCC 7E 7E ~RLGM S025 2A Energized Energized/

/Standby Standby 2R25- 12SVDC Distribution Energized Energized ~RLGM SOOl Cabinet 2A 2R25- 12SVDC Distribution Energized Energized ~ RLGM S002 Cabinet 2B 2R25- Energized Energized/

120/208V DIST PANEL 2J ~RLGM S029 /Standby Standby MPR-4121 B-8 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 2R25- 120/208VAC Instrument Available Available ~RLGM S064 Bus 2A- Div I 2R25- 120/208VAC Instrument Available Available ~RLGM S065 Bus 2B - Div II Not Yet Installed; 2R25- 120VAC Critical Instrument Energized Energized N/A See Sections 7.2 &

S066 Cabinet 2A 8.4 Not Yet Installed; 2R25- 120VAC Critical Instrument Energized Energized N/A See Sections 7.2 &

S067 Cabinet 2B 8.4 2R25- Emergency Lighting Cabinet Energized Energized ~RLGM S069 - Divll 2R25- Emergency Lighting Cabinet Energized Energized ~RLGM S094 - Div II 2R25- 125VDC Distribution Energized Energized ~RLGM S130 Cabinet 2E 2R26- 125VDC THROWOVER SW Standby/ Standby/

~RLGM M031A 2A Closed Closed 2R26- 125VDC THROWOVER SW Standby/ Standby/

~RLGM M031B 2B Closed Closed 2R26- 125VDC THROWOVER SW Standby/ Standby/

~RLGM M031C 2C Closed Closed 2R26- 125VDC THROWOVER SW Standby/ Standby/

~RLGM M031D 20 Closed Closed Not Yet Installed; 2R26-FLEX Transfer Switch 2A Normal Normal N/A See Sections 7.2 &

M126 8.4 Not Yet Installed; 2R26-FLEX Transfer Switch 2B Normal Normal N/A See Sections 7.2 &

M127 8.4 MPR-4121 B-9 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Not Yet Installed; 2R26-FLEX Transfer Switch 20 Normal Normal N/A See Sections 7.2 &

M129 8.4 Not Yet Installed; 2R26-FLEX Transfer Switch 2E Normal Normal N/A See Sections 7.2 &

M130 8.4 Not Yet Installed; 2R26- FLEX Fused Disconnect Standby Standby N/A See Sections 7.2 &

M132 Switch 2A 8.4 Not Yet Installed; 2R26- FLEX Fused Disconnect Standby Standby N/A See Sections 7.2 &

M133 Switch 2B 8.4 2R27-LOCAL STARTER 2E11-F008 Energized De-Energized ~ RLGM S096 2R42- 125/250VDC Station Energized Energized ~RLGM SOOlA Battery 2A 2R42- 125/250VDC Station Energized Energized ~RLGM SOOlB Battery 2B FLEX Mod Not Yet 2R42-Battery Charger 2A- Div I Energized Energized N/A Complete; See S026 Sections 7.2 & 8.4 FLEX Mod Not Yet 2R42-Battery Charger 2B - Div I Energized Energized N/A Complete; See S027 Sections 7.2 & 8.4 2R42-Battery Charger 20 - Div II Energized Energized ~RLGM S029 2R42-Battery Charger 2E - Div II Energized Energized ~RLGM S030 Not Yet Installed; 2R44- 2SOVDC/120VAC FLEX Energized Energized N/A See Sections 7.2 &

S006 Inverter 2A 8.4 MPR-4121 B-10 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Not Yet Installed; 2R44- 2SOVDC/120VAC FLEX Energized Energized N/A See Sections 7.2 &

S007 Inverter 28 8.4 2T47-SIGNAL CONVERTER R/V Operating Operating  ::!:RLGM KGOO 2T47-N001J,K SIGNAL CONV R/V Operating Operating  ::!:RLGM K602 2T47- N001M, N003 SIG CONV Operating Operating  ::!:RLGM K603 R/V 2T47-NODS, N007 SIG CONV R/V Operating Operating  ::!:RLGM K604 2T47-NOlO SIGNAL CONV R/V Operating Operating  ::!:RLGM KGOS Inaccessible/High 2T47-B009A Inlet Air TE- Div II Operating Operating N/A Dose; See Section N001J 7.1 Inaccessible/High 2T47- DW CLG Dome Area TE- Div Operating Operating N/A Dose; See Section N001K II 7.1 Inaccessible/High 2T47-B009A&B Inlet Air TE- Div II Operating Operating N/A Dose; See Section N001M 7.1 Inaccessible/High 2T47- DW CLG Midlevel Area TE-Operating Operating N/A Dose; See Section N003 Div II 7.1 Inaccessible/High 2T47- DW Lower Level Area TE-Operating Operating N/A Dose; See Section NODS Div II 7.1 Inaccessible/High 2T47- DW Lower Level Area TE-Operating Operating N/A Dose; See Section N007 Div II 7.1 MPR-4121 B-11 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Inaccessible/High 2T47- Sacrificial Shield Top TE-Operating Operating N/A Dose; See Section NOlO Div II 7.1 2T47- OW CLG CRD/Torus Area TR Operating Operating  ::?:RLGM R627 - Div II 2T48-NITROGEN STORAGE TANK Available Available  ::?:RLGM AOOl Repaired under 2T48- N2 TANKAM81ENT CAP andre-walked Available Available  ::?:RLGM 8002 VAPORIZER down; See Section 6.3.3.

2T48-HCVS Vent Control AOV Closed Closed/Open  ::::RLGM F082 2T48- HCVS Containment Closed Closed/Open  ::::RLGM F318 Isolation AOV 2T48- HCVS Containment Closed Closed  ::?:RLGM F319 Isolation AOV 2T48- HCVS Containment Closed Closed  ::?:RLGM F320 Isolation AOV 2T48- HCVS Containment Closed Closed/Open  ::?:RLGM F326 Isolation AOV Not Yet Installed; 2T48- Relief Valve Argon Supply Standby Standby N/A See Sections 7.2 &

F408 Overpressure Protection 8.4 2T48-8002 DISCH LINE SRV Standby Standby  :::: RLGM F465 2T48- 8002 DISCHARGE PCV (N2 Operating Operating  ::?:RLGM F468 system) 2T48-OW Pressure lnst 1/V- Div II Operating Operating  ::?:RLGM K6088 MPR-4121 B-12 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results 2T48- DW/Torus Pressure lnst 1/V Operating Operating 2: RLGM K620B - Div II 2T48-Torus Levellnst 1/V- Div II Operating Operating 2: RLGM K621B 2T48-TORUS AIR TEMP R/V Operating Operating 2: RLGM K624B 2T48-Torus Midrange PT- Div II Operating Operating 2: RLGM N008B 2T48-Torus Water TE- Div II Operating Operating 2: RLGM N009B 2T48-Torus Water TE- Div II Operating Operating 2: RLGM N009D 2T48-Torus Air TE- Div II Operating Operating 2: RLGM N009E 2T48-Torus Air TE- Div II Operating Operating 2: RLGM N009H 2T48- DW Narrow Range PT- Div Operating Operating 2: RLGM N020B II 2T48- Narrow Range Torus LT-Operating Operating 2: RLGM N021B Div II 2T48-DW Midrange PT- Div II Operating Operating 2: RLGM N023B 2T48- DW and Torus Narrow Operating Operating 2: RLGM R607B Range L/PR - Div II 2T48- DW/Torus Midrange PR-Operating Operating 2: RLGM R609 Div II 2T48-D/W MIDRANGE PI Operating Operating 2: RLGM R631B 2T48-TORUS MIDRANGE PI Operating Operating 2: RLGM R632B MPR-4121 B-13 RevisionO

Equipment Operating State HCLPF Screening Notes/Comments ID Description Normal Desired Results Not Yet Installed; 2X86-FLEX Connection Box 2A Standby Standby N/A See Sections 7.2 &

S003 8.4 Not Yet Installed; 2X86-FLEX Connection Box 2B Standby Standby N/A See Sections 7.2 &

S004 8.4 2Y52- DG FUEL OIL STORAGE Available Available ~RLGM AOOlA TANK 2A 2Y52-DIESEL 2A FUEL PUMP 2A1 Available Available ~ RLGM COOl A MPR-4121 B-14 RevisionO

Edwin I. Hatch Nuclear Plant - Units 1 and 2 Expedited Seismic Evaluation Process Report -

Fukushima Near-Term Task Force Recommendation 2.1 Enclosure 2 Required Actions and Schedule for Completion of ESEP Activities to NL-14-1989 Hatch Nuclear Plant- Units 1 and 2 Required Actions and Schedule for Completion of ESEP Activities Hatch Unit 1 Required Actions and Schedule for ESEL Items Not Installed as of Walkdowns/Report Issuance

1. Equipment Outage Required Scheduled Completion Number Required Action Date 1

• 1R26-M132 FLEX Fused Disconnect Switch 1A Does NOT require outage to After the item is installed, December 2016 walk down or install perform Seismic

• 1R26-M 133 FLEX Fused Disconnect Switch 1B modification (if modification is Walkdown, generate (2 years after ESEP Report

• 1 R26-M 136 FLEX Transfer Switch 1A necessary) HCLPF evaluations in submittal)

• 1 R26-M 137 FLEX Transfer Switch 1B accordance with EPRI

• 1 R26-M 139 FLEX Transfer Switch 1D 3002000704 and EPRI NP-6041-SL, and design/

• 1 R26-M140 FLEX Transfer Switch 1 E implement any

• 1T48-F408 Relief Argon Supply Overpressure modifications necessary to Protection meet ESEP requirements.

• 1X86-S003 600V FLEX Diesel Generator (FLEX Connection Box 1A)

• 1X86-S004 600V FLEX Diesel Generator (FLEX Connection Box 1B) 2

• 1P52-A027A BKUP Air Accumulator Tank A Requires outage to walk down After the item is installed, Spring outage 2018 or install modification (if perform Seismic

• 1P52-A027B BKUP Air Accumulator Tank B modification is necessary) Walkdown, generate (2 outages after December

• 1 P52-F1312 Relief Valve N2 Cylinder Supply HCLPF evaluations in 2014)

Manifold Overpressure Protection accordance with EPRI

• 1 R25-S066 120VAC Critical instrument Cabinet 1A 3002000704 and EPRI

• 1R25-S067 120VAC Critical instrument Cabinet 1B NP-6041-SL, and design/

• 1 R42-S026 Battery Charger 1A - Div I implement any modifications necessary to

• 1 R42-S027 Battery Charger 1B - Div I meet ESEP requirements.

• 1 R44-S006 250VDC/120VAC Inverter 1A

• 1R44-S007 250VDC/120VAC Inverter 1B E2-1 to NL-14-1989 Hatch Nuclear Plant- Units 1 and 2 Required Actions and Schedule for Completion of ESEP Activities Hatch Unit 1 Required Actions and Schedule for ESEL Items Not Installed as of Walkdowns/Report Issuance

1. Equipment Outage Required Scheduled Completion Number Required Action Date 3 NA NA Submit letter to NRC 90 days following completion summarizing results of of ESEP activities, no later Unit 1 Items 1 and 2 and than 90 days after Spring 2018 provide confirmation that outage (if an outage is plant modifications required).

associations with Items 1 and 2 are complete.

Continued next page for Unit 2 E2-2 to NL-14-1989 Hatch Nuclear Plant- Units 1 and 2 Required Actions and Schedule for Completion of ESEP Activities Hatch Unit 2 Required Actions and Schedule for ESEL Items Not Installed as of Walkdowns/Report Issuance

1. Equipment Number Description Remaining Scope Completion Date 1

• 2R26-M126 FLEX Transfer Switch 2A Does NOT require outage to After the item is installed, December 2016 walk down or install perform Seismic Walkdown,

• 2R26-M 127 FLEX Transfer Switch 2B modification (if modification is generate HCLPF evaluations (2 years after ESEP

• 2R26-M 129 FLEX Transfer Switch 2D necessary) in accordance with EPRI Report submittals)

• 2R26-M130 FLEX Transfer Switch 2E 3002000704 and EPRI NP-

• 2R42-S026 Battery Charger 2A - Div I 6041-SL, and

• 2R42-S027 Battery Charger 2B - Div I design/implement any necessary modifications

• 2T48-F408 Relief Argon Supply Overpressure necessary to meet ESEP Protection requirements.

• 2X86-S003 600V FLEX Diesel Generator (FLEX Connection Box 2A)

• 2X86-S004 600V FLEX Diesel Generator (FLEX Connection Box 2B) 2

• 2P52-A027A BKUP Air Accumulator Tank A Requires outage to walk down After the item is installed, Spring outage 2017 or install modification (if perform Seismic Walkdown,

• 2P52-A027B BKUP Air Accumulator Tank B modification is necessary) generate HCLPF evaluations (2 outages after December

• 2P52-F1228 Relief Valve N2 Cylinder Supply in accordance with EPRI 2014)

Manifold Overpressure Protection 3002000704 and EPRI NP-

• 2R25-S066 120VAC Critical instrument Cabinet 2A 6041-SL, and

• 2R25-S067 120VAC Critical instrument Cabinet 2B design/implement any

• 2R26-M 132 FLEX Fused Disconnect Switch 2A necessary modifications necessary to meet ESEP

• 2R26-M 133 FLEX Fused Disconnect Switch 2B requirements.

• 2R44-S006 250VDC/120VAC Inverter 2A

• 2R44-S007 250VDC/120VAC Inverter 2B E2-3 to NL-14-1989 Hatch Nuclear Plant- Units 1 and 2 Required Actions and Schedule for Completion of ESEP Activities Hatch Unit 2 Required Actions and Schedule for ESEL Items Not Installed as of Walkdowns/Report Issuance

1. Equipment Number Description Remaining Scope Completion Date 3 NA NA Submit letter to NRC 90 days following summarizing results of Unit 2 completion of ESEP Items 1 and 2 and provide activities, no later than 90 confirmation that plant days after Spring 2017 modifications associations with outage (if an outage is Items 1 and 2 are complete. required).

E2-4

Edwin I. Hatch Nuclear Plant - Units 1 and 2 Expedited Seismic Evaluation Process Report -

Fukushima Near-Term Task Force Recommendation 2.1 Enclosure 3 Table of Regulatory Commitments to NL-14-1989 Hatch Nuclear Plant - Units 1 and 2 Table of Regulatory Commitments Type Scheduled Commitment Completion Date One-Time Continuing Action Compliance (If Required)

Hatch Unit 1 Complete the remaining NTTF 2.1 X Within 90 days following Unit 1 ESEL walkdowns/evaluations completion of ESEP for items that are not currently activities, no later than 90 installed. These items are identified days after Spring 2018 in Attachment A of the Hatch Units outage (if an outage is 1 and 2 ESEP Report (Enclosure 1 required).

of this letter) and summarized in Enclosure 2.

Hatch Unit 2 Complete the remaining NTTF 2.1 X Within 90 days following Unit 2 ESEL walkdowns/evaluations completion of ESEP for items that are not currently activities, no later than 90 installed. These items are identified days after Spring 2017 in Attachment B of the Hatch Units outage (if an outage is 1 and 2 ESEP Report (Enclosure 1 required).

of this letter) and summarized in Enclosure 2.

E3-1