ML14090A236

Seismic Hazard and Screening Report (Central and Eastern United States (CEUS) Sites), Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-.

ML14090A236
Person / Time
Site:	Limerick
Issue date:	03/31/2014
From:	Jim Barstow Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RS-14-06910
Download: ML14090A236 (51)

Text

1 Exelon Generation RS-14-069 10 CFR 50.54(f) March 31, 2014 u.s. Nuclear Regulatory Commission Attn: Document Control Desk 11555 Rockville Pike, Rockville, MD 20852

References:

Limerick Generating Station, Units 1 and 2 Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353 Exelon Generation Company, LLC, Seismic Hazard and Screening Report (Central and Eastern United States (CEUS) Sites), Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident 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 Dai-ichi Accident, dated March 12,2012 2. NEI Letter, 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 4. Exelon Generation Company, LLC letter to the NRC, Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding the Seismic Aspects of Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident -1.5 Year Response for CEUS Sites, dated September 12, 2013 5. 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 6. NRC Letter, Endorsement of Electric Power Research Institute Final Draft Report 1025287, "Seismic Evaluation Guidance," dated February 15, 2013 7. EPRI Technical Report 3002000704, "Seismic Evaluation Guidance: Augmented Approach for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1: Seismic," dated May 2013 U.S. Nuclear Regulatory Commission NTTF 2.1 Seismic Response for CEUS Sites March 31, 2014 Page 2 On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued Reference 1 to all power reactor licensees and holders of construction permits in active or deferred status. Enclosure 1 of Reference 1 requested each addressee located in the Central and Eastern United States (CEUS) to submit a Seismic Hazard Evaluation and Screening Report within 1.5 years from the date of Reference

1. In Reference 2, the Nuclear Energy Institute (NEI) requested NRC agreement to delay submittal of the final CEUS Seismic Hazard Evaluation and Screening Reports so that an update to the Electric Power Research Institute (EPRI) ground motion attenuation model could be completed and used to develop that information.

NEI proposed that descriptions of subsurface materials and properties and base case velocity profiles be submitted to the NRC by September 12, 2013, with the remaining seismic hazard and screening information submitted by March 31, 2014. NRC agreed with that proposed path forward in Reference

3. In Reference 4, Exelon Generation Company, LLC (EGC) provided the description of subsurface materials and properties and base case velocity profiles for Limerick Generating Station, Units 1 and 2. Reference 5 contains industry guidance and detailed information to be included in the Seismic Hazard Evaluation and Screening Report submittals.

NRC endorsed this industry guidance in Reference

6. . The enclosed Seismic Hazard Evaluation and Screening Report for Limerick Generating Station, Units 1 and 2, provides the information described in Section 4 of Reference 5 in accordance with the schedule identified in Reference

2. As described in Enclosure 1, Limerick Generating Station, Units 1 and 2, meet the requirements of SPID Sections 3.2 and 7 (Reference

5) and therefore screen out and do not need to prepare an Expedited Seismic Evaluation Process (ESEP) Report in accordance with Reference

7. Additionally , no Seismic Risk Assessment or Spent Fuel Pool evaluation is needed. Limerick Generating Station, Units 1 and 2, will perform a High Frequency Confirmation evaluation as determined by NRC prioritization following submittal of all nuclear power plant Seismic Hazard Re-evaluations per Reference 1 . A list of regulatory commitments contained in this letter is provided in Enclosure

2. If you have any questions regarding this report, please contact Ron Gaston at (630) 657-3359. I declare under penalty of perjury that the foregoing is true and correct. Executed on the 31 sl day of March 2014. Respectfully submitted , James Barstow Director -Licensing

& Regulatory Affairs Exelon Generation Company, LLC U.S. Nuclear Regulatory Commission NTTF 2.1 Seismic Response for CEUS Sites March 31, 2014 Page 3

Enclosures:

1. Limerick Generating Station, Units 1 and 2, Seismic Hazard and Screening Report 2. Summary of Regulatory Commitments cc: Director, Office of Nuclear Reactor Regulation Regional Administrator

-NRC Region I NRC Senior Resident Inspector

-Limerick Generating Station NRC Project Manager, NRR -Limerick Generating Station Ms. Jessica A. Kratchman, NRR/JLD/PMB, NRC Mr. Eric E. Bowman, NRRlDPRlPGCB, NRC or Ms. Eileen M. McKenna, NRO/OSRAlBPTS, NRC Director, Bureau of Radiation Protection

-Pennsylvania Department of Environmental Resources R. R. Janati, Chief, Division of Nuclear Safety, Pennsylvania Department of Environmental Protection, Bureau of Radiation Protection Enclosure 1 Limerick Generating Station, Units 1 and 2 Seismic Hazard and Screening Report (46 pages)

S E IS M IC HAZA RD AND S CREEN I NG REP O R T IN RESPONSE TO THE 50.54(t) INFORMATION REQUEST REGARDING FUKUSHIMA NEAR-TERM TASK FORCE RECOMMENDATION 2.1: SEISMIC for the LIMERICK GENERATING STATION UNITS 1 & 2 3146 Sanatoga Road, Pottstown, PA 19464 Facility Operating License No. NPF*39 & NPF*85 NRC Docket No. 8TN 50*352 & 8TH 50-353 Correspondence No.: RS-14-069 Exelon Generation Company. LLC (Exelon) PO Box 805398 Chicago. 'L 6068Q.5398 Prepared by: Enercon 8eMceI. Inc. 600 Townpark Lane, Kennesaw.

GA 30144 Report Number: EXLNLIM085-PR.Q01.

Revlston 0 PdnIIdNama Pr8paIar:

MIfcheI McKay RevIewer:

Benjamin KOIbab Approver; Paul Hensen RECORD OF REVISIONS Revision Affected Pages 0 All Initial issue. Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 Description Contents Contents ...................................................

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i Tables ............

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iii Figures ...............................................................................................

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iv Executive Summary ................................................

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v 1 Introduction

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1-1 2 Seismic Hazard Reevaluation

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2-1 2.1 Regional and Local Geology ...................

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2-1 2.2 Probabilistic Seismic Hazard Analysis ................................................

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.. 2-2 2.2.1 Probabilistic Seismic Hazard Analysis Results ...................................

........... 2-2 2.2.2 Base Rock Seismic Hazard Curves .....................

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...................... 2-3 2.3 Site Response Evaluation

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.. 2-3 2.3.1 Description of Subsurface Material ................................................................ 2-3

2.3.2 Development

of Base Case Profiles and Nonlinear Material Properties

....... 2-5 2.3.3 Randomization of Base Case Profiles .................

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...................... 2-9 2.3.4 Input Spectra ............................................................................................... 2-10 2.3.5 Methodology

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.................................................................. 2-10 2.3.6 Amplification Functions

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.................. 2-10 2.3.7 Control Point Seismic Hazard Curves ..................

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2-15 2.4 Control Point Response Spectra (UHRS & GMRS) .............................................. 2-16 3 Plant DeSign Basis Ground Motion ..............................................................................

3-1 3.1 SSE Description of Spectral Shape ....................

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.. 3-1 3.2 Control Point Elevation

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................................... '" ................ 3-2 4 Screening Evaluation

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4-1 4.1 Risk Evaluation Screening (1 to 10Hz) ................................................................. .4-1 4.2 High Frequency Screening

(> 10 Hz) ..................................................................... .4-1 4.3 Spent Fuel Pool Evaluation Screening (1 to 10Hz) ..........................

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.4-2 Limerick Generating Station Report Number: EXLNLlM065-PR-001.

Revision 0 Correspondence No.: RS-14-069 Contents (cont'd.)

5 Interim Actions ...............................................................................................................

5-1 5.1 Expedited Seismic Evaluation Process ..........

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............... 5-1 5.2 Interim Evaluation of Seismic Hazard ................

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5-1 5.3 Seismic Walkdown Insights .........................................

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................ 5-2 5.4 Beyond-Design-Basis Seismic Insights ......................................................

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5-2 6 Conclusions

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....... 6-1 7 References

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7-1 Appendices A Additional Tables ...................

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A-1 Limerick Generating Sta t ion Report Number: EXLNLlM065-PR-001 , Rev i sion 0 Correspondence No.: RS-14-069 ii Tables Table 2.3.1-1 Summary of site geotechnical profile for LGS (Reference

14) ......................

...... 2-4 Table 2.3.2-1 (Not used) Table 2.3.2-2 Layer thicknesses, depths, and shear-wave velocities (Vs) for three profiles, the Limerick site ...........................

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2-6 Table 2.3.2-3 Kappa values and weights used for site response analyses ...............................

2-9 Table 2.4-1 UHRS and GMRS at control point for LGS (5% of critical damping response spectra) ...............................

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.................. 2-17 Table 3.1-1 Horizontal SSE for LGS (5% of crit i cal damping response spectrum)

................. 3-1 Table 5.4-1 HorizontallHS for LGS (5% of critical damping response spectrum)

.................. 5-3 Table A-1a Mean and fractile seismic hazard curves for PGA at LGS, 5% of critical damping ...................................

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A-1 Table A-1 b Mean and fractile seismic hazard curves for 25 Hz at LGS, 5% of critical damping ....................................

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A-2 Table A-1c Mean and fractile seismic hazard curves for 10 Hz at LGS, 5% of critical damping .....................

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............ A-2 Table A-1d Mean and fractile seismic hazard curves for 5 Hz at LGS, 5% of critical damping ............................

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A-3 Table A-1e Mean and fractile seismic hazard curves for 2.5 Hz at LGS, 5% of critical damping ...................................

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A-3 Table A-1f Mean and fractile seismic hazard curves for 1 Hz at LGS, 5% of critical damping .....................................................................................

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A-4 Table A-1g Mean and fractile seismic hazard curves for 0.5 Hz at LGS, 5% of critical damping ............................

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A-4 Table A-2 Amplification functions for LGS, 5% of critical damping ................

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A-5 Table A2-b1 Median AFs and sigmas for Model 1 , Profile 1, for 2 PGA levels ........................

A-7 Table A2-b2 Median AFs and sigmas for Model 2, Profile 1, for 2 PGA levels ........................

A-8 Limerick Generating Station Report Number: EXLNLlM065*PR

• 001, Revision 0 Correspondence No.: RS*14*069 i ii Figures Figure 2.3.2-1 Shear wave velocity profiles for the Limerick site ..............................................

2-6 Figure 2.3.6-1 Example suite of amplification factors (5% of critical damping pseudo absolute acceleration spectra) developed for the mean base-case profile (P1), EPRI rock modulus reduction and hysteretic damping curves (model M1), and base-case kappa at eleven loading levels of hard rock median peak acceleration values from 0.01g to 1.50g. M 6.5 and single-corner source model (Reference

3) .. 2-11 Figure 2.3.6-2 Example suite of amplification factors (5% of critical damping pseudo absolute acceleration spectra) developed for the mean base-case profile (P1), linear analyses (model M2), and base-case kappa at eleven loading levels of hard rock median peak acceleration values from 0.01 g to 1.50g. M 6.5 and single-corner source model (Reference

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...... 2-13 Figure 2.3.7-1 Control point mean hazard curves for spectral frequencies of 0.5, 1,2.5, 5, 10, 25 and 100 Hz (PGA) at LGS (5% of critical damping) ....................

............... 2-15 Figure 2.4-1 Plots of 1 E-4 and 1 E-5 UHRS and GMRS at control point for LGS (5% of critical damping response spectra) ......................................................

2-16 Figure 3.1-1 Horizontal SSE for LGS (5% of critical damping response spectrum)

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3-2 Figure 5.4-1 HorizontallHS and SSE for LGS (5% of critical damping response spectra) .... 5-3 Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 iv Executive Summary PURPOSE 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) issued a 50.54(f) letter (Reference

1) requesting information i n response to NRC Near-Term Task Force (NTTF) recommendations intended to clarify and strengthen the regulatory framework for protection against natural phenomena.

The 50.54(f) letter (Reference

1) requests that licensees and holders of construction permits under Title 10 Code of Federal Regulations Part 50 (Reference

2) reevaluate the seismic hazards at their sites using updated seismic hazard information and present-day regulatory guidance and methodologies. This report provides the information requested in items (1) through (7) of the "Requested Information" in Enclosure 1 of the 50.54(f) letter (Reference 1), pertaining to NTTF Recommendation 2.1: Seismic for Limerick Generating Station (LGS) in accordance with the documented intention of Exelon Generation Company, LLC transmitted to the NRC via letter dated April 29, 2013 (Reference 13). SCOPE In response to the 50.54(f) letter (Reference

1) and following the Screening, Prioritization and Implementation Details (SPID) industry guidance document (Reference 3), a seismic hazard reevaluation for LGS was performed to develop a Ground Motion Response Spectrum (GMRS) for comparison with the plant-level seismic capacity.

The new GMRS represents an alternative seismic demand determined using recently developed techniques. The new GMRS does not constitute a change in the plant design or licensing basis as described in the NRC letter dated February 20, 2014 (Reference 12). Section 1 provides an introduction.

Section 2 provides a summary of the LGS regional and local geology and seismicity, other major inputs to the seismic hazard reevaluation, and detailed seismic hazard results including definition of the GMRS. Seismic hazard analysis for LGS, including site response evaluation and GMRS development (Sections 2

.2, 2.3, and 2.4 of this report), was performed by the Electric Power Research Institute (Reference 16). A more in-depth discussion of the calculation methods used in the seismic hazard reevaluation can be found in References 3, 6, 7, 8, and 15. Section 3 describes the characteristics of the plant design basis ground motion for LGS. Section 4 provides a GMRS screening evaluation for LGS. Sections 5 and 6 discuss interim actions and conclusions, respectively, for LGS. CONCLUSIONS For LGS, the Safe Shutdown Earthquake envelopes the GMRS in the frequency range from 1 to 10 Hz. Therefore per the SPID Sections 3.2 and 7 (Reference 3), LGS screens out of further seismic risk assessments in response to NTTF 2.1: Seismic, including seismic probabilistic risk assessment (SPRA) or seismic margin assessment (SMA), as well as spent fuel pool integrity evaluations.

Additionally, LGS screens out of the Limerick Generating Station Report Number. EXLNLlM065-PR-001 , Revision 0 Correspondence No.: RS-14-069 v

Expedited Seismic Evaluation Process (ESEP) interim action per the "Augmented Approach" guidance document , Section 2.2 (Reference 4). Due to the GMRS exceeding the SSE in the frequency range above 10Hz, high frequency confirmations are needed for LGS in accordance with the SPID Sections 3.2 and 3.4 (Reference 3). Actions to address NTTF 2.1: Seismic for central and eastern United States nuclear plants will be performed in accordance with the schedule provided in the April 9, 2013 letter from the industry to the NRC (Reference 5), as agreed to by the NRC in the May 7, 2013 letter to the industry (Reference 23). limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 vi 1 Introduction 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). The NTTF was tasked with conducting a systematic review of NRC processes and regulations 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 requesting information to assure these recommendations would be addressed by all U.S. nuclear power plants (Reference 1). The 50.54(f) letter (Reference

1) requests that licensees and holders of construction permits under Title 10 Code of Federal Regulations Part 50 (10CFR50) (Reference

2) reevaluate the seismic hazards at their sites using updated seismic hazard information and present-day regulatory guidance and methodologies. Depending on the outcome of the comparison between the reevaluated seismic hazard and the current site-specific design basis, performance of a seismic risk assessment may be necessary.

Risk assessment approaches acceptable to the NRC staff include a seismic probabilistic risk assessment (SPRA), or a seismic margin assessment (SMA). Based upon the risk assessment results, the NRC staff will determine whether additional regulatory actions are necessary to provide additional protection against the updated hazards. This report provides the information requested in items (1) through (7) of the "Requested Information" in Enclosure 1 of the 50.54(f) letter (Reference 1), pertaining to NTTF Recommendation 2.1: Seismic for Limerick Generating Station (LGS), located in Montgomery County, Pennsylvania in accordance with the documented intention of Exelon Generation Company, LLC (Exelon) transmitted to the NRC via letter dated April 29, 2013 (Reference 13). In providing this information LGS followed the Screening, Prioritization, and Implementation Details (SPID) industry guidance document (Reference 3). The "Augmented Approach" guidance document (Reference

4) defines interim actions/evaluations for addressing a higher seismic hazard relative to the plant's current design/licensing basis prior to completion of the seismic risk assessments to demonstrate additional seismic margin. This short term aspect of the Augmented Approach is referred to as the Expedited Seismic Evaluation Process (ESEP). In response to NTTF Recommendation 2.3, seismic walkdowns for LGS have been performed as initially documented and supplemented in Exelon Correspondence Numbers RS-12-171 and RS-13-138 (References 11 and 29), respectively, to satisfy the 50.54(f) letter (Reference 1). The original geologic and seismic siting investigations for LGS were performed in accordance with Appendix A to 10 CFR Part 100 (Reference

17) and meet General Design Criterion 2 in Appendix A to 10CFR50 (Reference 2). The Safe Shutdown Earthquake Ground Motion (SSE) was developed in accordance with Appendix A to 1 OCFR 100 (Reference

17) and used for the design of seismic Category I structures, systems and components (SSC). See Section 3 of this report for further discussion on Limerick Generating Station 1-1 Report Number. EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 the development of the LGS SSE. All seismic Category I SSCs are analyzed under the loading conditions of the Safe Shutdown Earthquake (SSE) and Operating Basis Earthquake (OBE). Since the two earthquakes vary in intensity, the design of seismic Category I SSCs to resist each earthquake and other loads is based on levels of material stress, or load factors, whichever is applicable, and yield margins of safety appropriate for each earthquake.

The margins of safety provided for safety-related SSCs for the SSE are sufficiently large to ensure that their design functions are not jeopardized (Reference 9, Section 3.2.1). In response to the 50.54(f) letter (Reference

1) and following the guidance in the SPID (Reference 3), a seismic hazard reevaluation for LGS was performed.

For screening purposes, a Ground Motion Response Spectrum (GMRS) was developed. Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 1-2 2 Seismic Hazard Reevaluation LGS is located on the east bank of the Schuylkill River in Limerick Township of Montgomery County, Pennsylvania, approximately 4 river miles downriver from Pottstown, 35 river miles upriver from Philadelphia , and 49 river miles above the confluence of the Schuylkill with the Delaware River (Reference 9, Section 1.1). LGS is located in the Triassic Lowland section of the Piedmont physiographic province.

The area is within the Newark-Gettysburg basin, which is underlain by red sandstones, shales and siltstones of the Triassic Newark Group. These sedimentary basin deposits are gently tilted and warped, and are cut by diabase dikes and sills and by minor faulting.

Some minor Jura-Triassic faults occur near the site; detailed studies carried out by LGS show that they are not significant to the construction and operation of the plant. The principal plant structures are founded on competent bedrock, about 100 feet above the river. Bedrock at the site, which consists of Triassic siltstone, sandstone, and shale, is moderately to closely jointed, and joints are generally vertical to nearly vertical (Reference 9, Section 2.5). Earthquake activity in historic time within 200 miles of the site has been moderate. Zones of major earthquakes in the eastern United States are far away, and have not had an appreciable effect at the site. Evaluation of tectonic structures and the historical seismic record indicate a design intensity of VII (Modified Mercalli Scale) is adequately conservative for the site. Intensity VII corresponds to a peak ground acceleration of 0.13g; for additional conservatism, 0.15g has been adopted for the SSE. (Reference 9, Section 2.5) 2.1 REGIONAL AND LOCAL GEOLOGY The Limerick site is located in the Triassic Lowland section of the Piedmont physiographic province. The northeast-southwest trending Piedmont province is an eroded plateau of low relief and rolling topography. The surface of the plateau slopes gently to the southeast.

The Piedmont is divided into an upland and a lowland section. The less rugged lowland section, in which LGS is located, is north and west of the Piedmont uplands and is formed largely on shales and sandstones of Triassic-age (Reference 9, Section 2.5.1.1.1).

The dominant structural feature in the region surrounding the site is the Appalachian Orogenic Belt (Reference 9, Section 2.5.1.1.3). This part of the Appalachian Piedmont in Pennsylvania, New Jersey, and Maryland is typified by the presence of several Triassic basins such as the Culpeper, Gettysburg, and Newark (Reference 9, Section 2.5.2.2.2). The site is located approximately 3 miles southeast of Pottstown, Pennsylvania, adjacent to the Schuylkill River. The principal plant structures are located on a broad ridge, approximately 100 feet above the river. Bedrock , encountered at shallow depths, consists predominantly of red siltstone, sandstone, and shale of late Triassic-age. The soils are residual, derived from the weathering of the underlying bedrock. Minor Triassic-age faults, inactive since Middle Mesozoic time, occur to the west and south of the construction area. Limerick Generating Station Report Number: EXLNLlM065-PR-001. Revision 0 Correspondence No.: RS-14-069 2-1 Fracture zones with a few inches of offset were encountered in the excavation; however, they are not significant to the plant structures. (Reference 9, Section 2.5.1.2.1) 2.2 PROBABILISTIC SEISMIC HAZARD ANALYSIS 2.2.1 Probabilistic Seismic Hazard Analysis Results In accordance with the SO.S4(f) letter (Reference

1) and following the guidance in the SPID (Reference 3), a probabilistic seismic hazard analysis (PSHA) was completed using the recently developed Central and Eastern United States Seismic Source Characterization (CEUS-SSC) for Nuclear Facilities (Reference

6) together with the updated EPRI Ground-Motion Model (GMM) for the CEUS (Reference 7). For the PSHA, a lower-bound moment magnitude of 5.0 was used, as specified in the SO.S4(f) letter (Reference 1). For the PSHA, the CEUS-SSC background seismic sources out to a distance of 400 miles (640 km) around LGS were included. This distance exceeds the 200 mile (320 km) recommendation contained in NRC Reg. Guide 1.208 (Reference

15) and was chosen for completeness.

Background sources included in this site analysis are the following: 1. Atlantic Highly Extended Crust (AHEX) 2. Extended Continental Crust-Atlantic Margin (ECC_AM) 3. Great Meteor Hotspot (GMH) 4. Mesozoic and younger extended prior -narrow (MESE-N) 5. Mesozoic and younger extended prior -wide (MESE-W) 6. Midcontinent-Craton alternative A (MIDC_A) 7. Midcontinent-Craton alternative B (MIDC_B) 8. Midcontinent-Craton alternative C (MIDC_C) 9. Midcontinent-Craton alternative D (MIDC_D) 10. Northern Appalachians (NAP) 11. Non-Mesozoic and younger extended prior -narrow (NMESE-N)

12. Non-Mesozoic and younger extended prior -wide (NMESE-W)

13. Paleozoic Extended Crust narrow (PEZ_N) 14. Paleozoic Extended Crust wide (PEZ_W) 15. St. Lawrence Rift, including the Ottawa and Saguenay grabens (SLR) 16. Study region (STUDY _R) For sources of large magnitude earthquakes, designated Repeated Large Magnitude Earthquake (RLME) sources in CEUS-SSC (Reference 6), the following sources lie within 1,000 km of the site and were included in the analysis:

1. Charleston

2. Charlevoix

3. Wabash Valley For each of the above background and RLME sources, the mid-continent version of the updated CEUS EPRI GMM was used. Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 2-2 2.2.2 Base Rock Seismic Hazard Curves Consistent with the SPID, Section 2.5.3 (Reference 3), base rock seismic hazard curves are not provided as the site amplification approach referred to as Method 3 has been used. Seismic hazard curves are shown below in Section 2.3.7 at the SSE control point elevation. 2.3 SITE RESPONSE EVALUATION Following the guidance contained in Seismic Enclosure 1 of the 50.54(f) letter (Reference

1) and the SPID, Section 2.4 (Reference

3) for nuclear power plant sites that are not founded on hard rock (considered as having a shear wave velocity of at least 9285 fps), a site response analysis was performed for LGS. 2.3.1 Description of Subsurface Material The Limerick site is located in the Newark-Gettysburg Triassic Basin of southeastern Pennsylvania.

The general site conditions consist of about 0 to 10 ft. (3.0m) of Cretaceous residual soils (clays, silts and sands with some gravel-sized rock fragments) over about 8,000 ft. (2,438 m) of sound Triassic sedimentary rocks with a basement of hard crystalline rocks (Reference 14). Table 2.3.1-1 shows the idealized profile of geotechnical properties from the site (reproduced from Reference 14). Limerick Generating Station Report Number: EXLNLlM065-PR-001 , Rev i sion 0 Correspondence No.: RS-14-069 2-3 Table 2.3.1-1 Summary of site geotechnical profile for LGS (Reference

14) Elevations of Layer Boundaries Range in Soil/Rock Shear Compressional Under Reactor Thickness Description and Density Wave Wave Velocity Poisson's Buildings Across Site (pet) Velocit,Y ratio (ft.) Age (fps)e. (fps)e.f (ft., MSL) Cretaceous stiff UFSAR: UFSAR: clayey silt , N/A N/A sandy silt , and 214 a to 204 0-10 silty fine sand 126-141 N/A with some ISFSI: ISFSI: gravel-sized rock fragments 875-1000 1800 Triassic UFSAR: UFSAR: Brunswick 5800-6100 7700-20000d 204 b to -7BOOe BOOO lithofacies, 140-162 0.30-0.33 hard siltstone, sandstone and ISFSI: ISFSI: shale 1900-5000 3500-BOOO Paleozoic and -7BOO and below N/A Precambrian N/A N/A N/A N/A basement rocks a .. FInish grade elevation IS nominally 217 ft. MSL around the main power block. The elevation shown In the table represents original grade before excavation and backfill.

Type I Fill was used for site grading around the main power block. UFSAR Section 2.5.4.2.2.5 states that the dynamic properties of Type I Fill have not been measured. The density is assumed to be 140 pcf in the design evaluations.

b The SSE and IPEEE HCLPF control point elevations are at the top of bedrock , at EI. 204 ft. MSL. e Bottom of the deepest foundation is at EI. 174ft. MSL, within the unweathered Brunswick lithofacies.

d UFSAR Section 2.5.4.2.1 indicates that the variation in compressional wave velocities in the immediate vicinity of the power block is significantly less than that over the entire site. The unbiased standard-deviation range is estimated to be 10950-12810 fps in the power block area. e The ISFSI geotechnical investigation and UFSAR provide significantly different ranges for the bedrock shear wave velocity and compressional wave velocity. Consequently, the reported values from each reference are reported separately.

f The compressional and shear wave velocities were measured near the surface of the bedrock. Limerick Generating S t ation Report Number: EXLNLlM065-PR-001.

Rev i sion 0 Correspondence No.: RS-14-069 2-4

2.3.2 Development

of Base Case Profiles and Nonlinear Material Properties Table 2.3.1-1 shows the recommended shear-wave velocities and unit weights versus depth for the profile. Based on Table 2.3.1-1 and the location of the SSE control point at an elevation of 204 ft. MSL (62.2m) (Reference

14) (see Section 3.2 for further control point discussion) the profile consists of about 8,000 ft. (2,438m) of firm rock overlying hard crystalline basement rock. Shear-wave velocities for the profile reported in the UFSAR likely were based on measurements of compressional-wave velocities (Reference

14) through refraction surveys and assumed Poisson ratios. More recent downhole testing at the nearby independent spent fuel storage installation (ISFSI) provided significantly different ranges for the firm rock shear-wave velocities (Reference 14). The narrow range in shear-wave velocity for the UFSAR is from 5,800 to 6,100 fps (1,768 to 1,859 m/s) (Reference 14). The larger range in shear-wave velocity for the ISFSI is from 1,900 to 5,000 fps (579 to 1,524 m/s) (Reference 14). Since the ISFSI measurements reflect more recent testing they were used to develop the mean or best-estimate base-case firm rock profile. To develop the mean or best-estimate base-case firm rock profile, the shear-wave velocity of 3,452 fps (1,052m/s) was assumed to reflect the shallow portion of the profile. Provided the materials to basement depth reflect similar sedimentary rocks and age, the shear-wave velocity gradient for sedimentary rock of 0.5 m/s/m (Reference

3) was assumed to be appropriate for the site. The shallow shear-wave velocity of 3,452 fps (1,052m/s) was taken at the surface of the profile with the velocity gradient applied at that point, resulting in a base-case shear-wave velocity of about 7,400 fps (2,255m/s) at a depth of 8,000 ft. (2,438m).

The mean or best estimate base-case profile is shown as profile P1 in Figure 2.3.2-1. Based on the range of shear-wave velocities that reflect either measured wave velocities and assumed Poisson ratios, or the more recent measurements at the ISFSI, a scale factor of 1.57 was adopted to reflect the lower range base-case.

The scale factor of 1.57 reflects a 0llin of about 0.35 based on the SPID (Reference

3) 10 th and 90 th fractiles which implies a 1.28 scale factor on all. Using the best estimate or mean base-case profile (P1), the depth independent scale factor of 1.57 was applied to develop the lower range base-case profile (P2). Base-case profiles P1 and P2 have a mean depth below the SSE control point of 8,000 ft. (2,438m) to hard reference rock, randomized

+/- 2,401 ft. (+/- 732m). Upper range profile P3 was based on the USFAR shear-wave velocity at the SSE control pOint of 5800-6100 fps (1,768 to 1,859 m/s) with an assumed velocity gradient for sedimentary rock of 0.5 m/s/m (Reference 3). Profile P3 reaches the hard-rock shear-wave velocity of 9,285 fps at a depth of 6,734 ft (2,052 m). The base-case profiles (P1, P2, and P3) are shown in Figure 2.3.2-1 and listed in Table 2.3.2-2. The depth randomization of profiles P1 and P2 reflect +/- 30% of the depth to provide a realistic broadening of the fundamental resonance rather than reflect actual random variations to basement shear-wave velocities across a footprint.

Limerick Generating Station Report Number: EXlNLlM065

-PR-001, Revision 0 Correspondence No.: RS-14-069 2-5 Vs profiles for Limerick Site Vs 1ft/sec) o 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 o 500 1000 1500 2000 2500 3000 -3500 4000 'S. 4500 5000 5500 6000 6500 7000 7500 8000 8500 \ \ \ \ , \. "-1\ \ \ \ \ , \. \. '-1 \ \ \ 1\ "-"-\ .... .... .... .... -Profile 1 \. '\ -Profile 2 \. 1\ -Profile 3 '\ '\ 'L " "\ "\ ... "\ , Figure 2.3.2-1 Shear wave velocity profiles for the Limerick site Table 2.3.2-2 Layer thicknesses, depths , and shear-wave velocities (Vs) for three profiles , the Limerick site Profile 1 Thickness Depth Vs Thickness (ft. ) (ft.) (fps) 0 3452 10.0 10.0 3452 10.0 20.0 3457 10.0 30.0 3462 10.0 40.0 3467 10.0 50.0 3472 10.0 60.0 3477 10.0 70.0 3482 10.0 80.0 3487 10.0 90.0 3492 10.0 100.0 3497 10.0 110.0 3502 10.0 120.0 3507 10.0 130.0 3512 10.0 140.0 3517 10.0 150.0 3522 10.0 160.0 3527 Limerick Generat i ng Station Report Number. EXLNLlM065-PR-001 , Revis i on 0 Correspondence No.: RS-14-069 (ft.) 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 Profile 2 Depth (ft.) 0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 110.0 120.0 130.0 140.0 150.0 160.0 Profile 3 Vs Thickness Depth Vs (fps) (ft. ) (ft.) (fps) 2209 0 5952 2209 10.0 10.0 5952 2213 10.0 20.0 5957 2216 10.0 30.0 5962 2219 10.0 40.0 5967 2222 10.0 50.0 5972 2225 10.0 60.0 5977 2229 10.0 70.0 5982 2232 10.0 80.0 5987 2235 10.0 90.0 5992 2238 10.0 100.0 5997 2241 10.0 110.0 6002 2245 10.0 120.0 6007 2248 10.0 130.0 6012 2251 10.0 140.0 6017 2254 10.0 150.0 6022 2257 10.0 160.0 6027 2-6 Profile 1 Thickness Depth Vs Thickness (ft.) (ft.) (fps) 10.0 170.0 3532 10.0 180.0 3537 10.0 190.0 3542 10.0 200.0 3547 10.0 210.0 3552 10.0 220.0 3557 10.0 230.0 3562 10.0 240.0 3567 10.0 250.0 3572 10.0 260.0 3577 10.0 270.0 3582 10.0 280.0 3587 10.0 290.0 3592 10.0 300.0 3597 10.0 310.0 3602 10.0 320.0 3607 10.0 330.0 3612 10.0 340.0 3617 10.0 350.0 3622 10.0 360.0 3627 10.0 370.0 3632 10.0 380.0 3637 10.0 390.0 3642 10.0 400.0 3647 10.0 410.0 3652 10.0 420.0 3657 10.0 430.0 3662 10.0 440.0 3667 10.0 450.0 3672 10.0 460.0 3677 10.0 470.0 3682 10.0 480.0 3687 10.0 490.0 3692 10.0 500.0 3695 164.0 664.0 3741 164.0 828.1 3823 164.0 992.1 3905 164.0 1156.1 3987 164.0 1320.2 4069 164.0 1484.2 4151 164.0 1648.3 4233 Limerick Generating Station Report Number: EXLNLlM065*PR*001, Revision 0 Correspondence No.: RS*14*069 (ft.) 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 164.0 164.0 164.0 164.0 164.0 164.0 164.0 Profile 2 Profile 3 Depth Vs Thickness Depth Vs (ft.) (fps) (ft.) (ft.) (fps) 170.0 2261 10.0 170.0 6032 180.0 2264 10.0 180.0 6037 190.0 2267 10.0 190.0 6042 200.0 2270 10.0 200.0 6047 210.0 2273 10.0 210.0 6052 220.0 2277 10.0 220.0 6057 230.0 2280 10.0 230.0 6062 240.0 2283 10.0 240.0 6067 250.0 2286 10.0 250.0 6072 260.0 2289 10.0 260.0 6077 270.0 2293 10.0 270.0 6082 280.0 2296 10.0 280.0 6087 290.0 2299 10.0 290.0 6092 300.0 2302 10.0 300.0 6097 310.0 2305 10.0 310.0 6102 320.0 2309 10.0 320.0 6107 330.0 2312 10.0 330.0 6112 340.0 2315 10.0 340.0 6117 350.0 2318 10.0 350.0 6122 360.0 2321 10.0 360.0 6127 370.0 2325 10.0 370.0 6132 380.0 2328 10.0 380.0 6137 390.0 2331 10.0 390.0 6142 400.0 2334 10.0 400.0 6147 410.0 2337 10.0 410.0 6152 420.0 2341 10.0 420.0 6157 430.0 2344 10.0 430.0 6162 440.0 2347 10.0 440.0 6167 450.0 2350 10.0 450.0 6172 460.0 2353 10.0 460.0 6177 470.0 2357 10.0 470.0 6182 480.0 2360 10.0 480.0 6187 490.0 2363 10.0 490.0 6192 500.0 2365 10.0 500.0 6197 664.0 2394 164.0 664.0 6241 828.1 2447 164.0 828.1 6323 992.1 2499 164.0 992.1 6405 1156.1 2552 164.0 1156.1 6487 1320.2 2604 164.0 1320.2 6569 1484.2 2657 164.0 1484.2 6651 1648.3 2709 164.0 1648.3 6733 2-7 Profile 1 Thickness Depth Vs Thickness (ft.) (ft.) (ftl 164.0 1812.3 4315 164.0 164.0 1976.4 4397 164.0 164.0 2140.4 4479 164.0 164.0 2304.4 4561 164.0 164.0 2468.5 4643 164.0 164.0 2632.5 4725 164.0 164.0 2796.6 4807 164.0 164.0 2960.6 4889 164.0 164.0 3124.6 4971 164.0 164.0 3288.7 5053 164.0 164.0 3452.7 5135 164.0 164.0 3616.8 5217 164.0 164.0 3780.8 5299 164.0 164.0 3944.9 5381 164.0 164.0 4108.9 5463 164.0 164.0 4272.9 5545 164.0 164.0 4437.0 5627 164.0 164.0 4601.0 5709 164.0 164.0 4765.1 5791 164.0 164.0 4929.1 5873 164.0 164.0 5093.1 5955 164.0 164.0 5257.2 6037 164.0 164.0 5421.2 6119 164.0 164.0 5585.3 6201 164.0 164.0 5749.3 6283 164.0 164.0 5913.4 6365 164.0 164.0 6077.4 6448 164.0 164.0 6241.4 6530 164.0 164.0 6405.5 6612 164.0 164.0 6569.5 6694 164.0 164.0 6733.6 6776 164.0 164.0 6897.6 6858 164.0 164.0 7061.6 6940 164.0 164.0 7225.7 7022 164.0 164.0 7389.7 7104 164.0 164.0 7553.8 7186 164.0 164.0 7717.8 7268 164.0 164.0 7881.9 7350 164.0 117.7 7999.6 7409 117.7 3280.8 11280.4 9285 3280.8 Limerick Generating Station Report Number EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 Profile 2 Profile 3 Depth Vs Thickness Depth Vs (ft.) (fps) (ft.) LftJ (fps) 1812.3 2762 164.0 1812.3 6815 1976.4 2814 164.0 1976.4 6897 2140.4 2867 164.0 2140.4 6979 2304.4 2919 164.0 2304.4 7061 2468.5 2972 164.0 2468.5 7143 2632.5 3024 164.0 2632.5 7225 2796.6 3077 164.0 2796.6 7307 2960.6 3129 164.0 2960.6 7389 3124.6 3182 164.0 3124.6 7471 3288.7 3234 164.0 3288.7 7553 3452.7 3287 164.0 3452.7 7635 3616.8 3339 164.0 3616.8 7717 3780.8 3391 164.0 3780.8 7799 3944.9 3444 164.0 3944.9 7881 4108.9 3496 164.0 4108.9 7963 4272.9 3549 164.0 4272.9 8045 4437.0 3601 164.0 4437.0 8127 4601.0 3654 164.0 4601.0 8209 4765.1 3706 164.0 4765.1 8291 4929.1 3759 164.0 4929.1 8373 5093.1 3811 164.0 5093.1 8455 5257.2 3864 164.0 5257.2 8537 5421.2 3916 164.0 5421.2 8619 5585.3 3969 164.0 5585.3 8701 5749.3 4021 164.0 5749.3 8783 5913.4 4074 164.0 5913.4 8865 6077.4 4126 164.0 6077.4 8947 6241.4 4179 164.0 6241.4 9029 6405.5 4231 164.0 6405.5 9111 6569.5 4284 164.0 6569.5 9193 6733.6 4336 164.0 6733.6 9275 6897.6 4389 164.0 6897.6 9285 7061.6 4441 164.0 7061.6 9285 7225.7 4494 164.0 7225.7 9285 7389.7 4546 164.0 7389.7 9285 7553.8 4599 164.0 7553.8 9285 7717.8 4651 164.0 7717.8 9285 7881.9 4704 164.0 7881.9 9285 7999.6 4742 117.7 7999.6 9285 11280.4 9285 3280.8 11280.4 9285 2-8 2.3.2.1 Shear Modulus and Damping Curves No site-specific nonlinear dynamic material properties were determined in the initial siting of the LGS for sedimentary rocks. The rock material over the upper 500 ft. (150 m) was assumed to have behavior that could be modeled as either linear or non-linear.

To represent this potential for either case in the upper 500 ft. of sedimentary rock at the Limerick site, two sets of shear modulus reduction and hysteretic damping curves were used. Consistent with the SPID (Reference 3), the EPRI rock curves (model M1) were considered to be appropriate to represent the upper range nonlinearity likely in the materials at this site and linear analyses (model M2) were assumed to represent an equally plausible alternative rock response across loading levels. For the linear analyses, the low strain damping from the EPRI rock curves were used as the constant damping values in the upper 500 ft. (150m). 2.3.2.2 Kappa For the Limerick site, kappa estimates were determined using Section 8-5.1.3.1 of the SPID (Reference

3) for a firm CEUS rock site. Kappa for a firm rock site with at least 3,000 ft. (1 km) of sedimentary rock may be estimated from the average S-wave velocity over the upper 100 ft. (V s100) of the subsurface profile while for a site with less than 3,000 ft. (1 km) of firm rock, kappa may be estimated with a Q s of 40 below 500 ft. combined with the low strain damping from the EPRI rock curves and an additional kappa of 0.006s for the underlying hard rock. For the Limerick site, with 8,000 ft. (2,438m) of firm sedimentary rock below the SSE , kappa estimates were based on the average wave velocity over the top 100 ft. (30m) of the three base-case profiles P 1, P2, and P3. For the three profiles the corresponding average (100 ft., 30m) shear-wave velocities were: 3,475 fps (1,059 m/s), 2,223 fps (678 m/s), and 5,974 fps (1,821 m/s) with corresponding kappa estimates of 0.023s, 0.036s, and 0.012s. The range in kappa about the best estimate base-case value of 0.023s (profile P1) is roughly 1.6 and was considered to adequately reflect epistemic uncertainty in low strain damping (kappa) for the profile. Table 2.3.2-3 Kappa values and weights used for site response analyses Velocity Profile Kappa (s) Weights P1 0.023 0.4 P2 0.036 0.3 P3 0.012 0.3 G/G max and Hysteretic Damping Curves M1 0.5 M2 0.5 2.3.3 Randomization of Base Case Profiles To account for the aleatory variability in dynamic material properties that is expected to occur across a site at the scale of a typical nuclear facility, variability in the assumed shear-wave velocity profiles has been incorporated in the site response calculations. For the Limerick site, random shear wave velocity profiles were developed from the base case profiles shown in Figure 2.3.2-1. Consistent with the discussion in Appendix 8 of the SPID (Reference 3), the velocity randomization procedure made use of random field Limerick Generating Station Report Number: EXLNLlM065-PR-001 , Revision 0 Correspondence No.: RS-14-069 2-9 models which describe the statistical correlation between layering and shear wave velocity.

The default randomization parameters developed in Reference 8 for United States Geological Survey (USGS) "A" site conditions were used for this site. Thirty random velocity profiles were generated for each base case profile. These random velocity profiles were generated using a natural log standard deviation of 0.25 over the upper 50 ft. and 0.15 below that depth. As specified in the SPID (Reference 3), correlation of shear wave velocity between layers was modeled using the footprint correlation model. In the correlation model, a limit of +/-2 standard deviations about the median value in each layer was assumed for the limits on random velocity fluctuations.

2.3.4 Input

Spectra Consistent with the guidance in Appendix B of the SPID (Reference 3), input Fourier amplitude spectra were defined for a single representative earthquake magnitude (M 6.5) using two different assumptions regarding the shape of the seismic source spectrum (single-corner and double-corner).

A range of 11 different input amplitudes (median peak ground accelerations (PGA) ranging from 0.01 g to 1.5g) were used in the site response analyses.

The characteristics of the seismic source and upper crustal attenuation properties assumed for the analysis of the Limerick site were the same as those identified in Tables B-4, B-5, B-6 and B-7 of the SPID (Reference

3) as appropriate for typical CEUS sites. 2.3.5 Methodology To perform the site response analyses for the Limerick site, a random vibration theory (RVT) approach was employed. This process utilizes a simple, efficient approach for computing site-specific amplification functions and is consistent with existing NRC guidance and the SPID (Reference 3). The guidance contained in Appendix B of the SPID (Reference

3) on incorporating epistemic uncertainty in shear-wave velocities , kappa, non-linear dynamic properties and source spectra for plants with limited at-site information was followed for the Limerick site. 2.3.6 Amplification Functions The results of the site response analysis consist of amplification factors (5% of critical damping pseudo absolute response spectra) which describe the amplification (or amplification) of hard reference rock motion as a function of frequency and input reference rock amplitude. The amplification factors are represented in terms of a median amplification value and an associated standard deviation (sigma) for each spectral frequency and input rock amplitude.

Consistent with the SPID (Reference

3) a minimum median amplification value of 0.5 was employed in the present analysis.

Figure 2.3.6-1 illustrates the median and +/-1 standard deviation in the predicted amplification factors developed for the eleven loading levels parameterized by the median reference (hard rock) peak acceleration (0.01g to 1.50g) for profile P1 and EPRI rock G/G max and hysteretic damping curves. The variability in the amplification factors results from variability in shear-wave velocity, depth to hard rock, and modulus reduction and hysteretic damping curves. To illustrate the effects of nonlinearity at the Limerick site, Figure 2.3.6-2 shows the corresponding amplification factors developed with linear analyses (model M2). Tabulated values of the amplification factors are provided in Appendix A. Limerick Generating Station Report Number. EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 2-10 c: ... 00 , ....... 9 oW <0 U =--... -... 0 , ..... 0 ::! ,....., 0.... E a: 7 INPUT MOTION O.OlG 7 INPUT MOTICtI O.OSG ::! '3 c ... ::! , .... +' iO U 0 .,.... 9 0.... E a: t INPUT MOTION O. tOG 7 INPUT !1OTION 0.21); 9 '3 c ... 09 :! +' iO U 4=0 0 ..... 0 :! ... 0.... E a: ... -, INPUT MOTION O. 3lG , INPUT !1OTION 0.40G :! 9 10 -1 Hl 0 10 1 10 2 10 -] 10 0 10 1 10 2 F (Hz) Freguency (Hz) AMPLIFICATION, LIMERICK, M1P1Kl M 1 CORNER: PAGE 1 OF c Figure 2.3.6-1 Example suite of amplification factors (5% of critical damping pseudo absolute acceleration spectra) developed for the mean base-case profile (P1), EPRI rock modulus reduction and hysteretic damping curves (model M1), and base-case kappa at eleven loading levels of hard rock median peak acceleration values from 0.01 g to 1.50g. M 6.5 and single-corner source model (Reference

3) Limerick Generating Station Report Number: EXLNLlM065-PR-001.

Revision 0 Correspondence No.: RS-14-069 2-11 c-09 ..... III U .... 4-0 0 c.... E a: -1 c-..... jQ u u*" g .-. a... I! a: INPUT MOTiai O. SOG 1 II'FUT I'KlTlai O.75G 9 i IIflUT ttOTJai 1. 00(; i II'FUT J1OTICl'I I. 2SG 9 9

c 09 ..... 10 U ,,.., 9 a... E a: -1 INPUT 1.SOG 9 Limerick Generating Station 10 -1 10 0 10 1 10 2 (Hz) AMPLIFICATION, LIMERICK, M1PIKl M 6.5, 1 CORNER; PAGE OF Figure 2.3.6-1 continued Report Number: EXLNLlM065-PR-001.

Revision 0 Correspondence No.: RS-14-069 2-12 c-o 9 . ..., It! tJ a... E a: -I 9 c-o,::! ..... +' II] (.J ..... '::! a... E a: ... I e c:-+' It! U ..... 0 a... e a: "'-'-,..-...,... _ ... _-INPUT MOTION O.OlG ......... * =---....... -II'flUT "OTION O.lOC INPUT NOTION O.30G 0 .... 0 "j e '::! 0 '::! .... I e ... I --. ... _--INPUT NOTION O.OSG . ----ItflUT MDTIO'i O. 20G .... .... ...... II'f'lIT 1'I0TIO'i O.4OG 10 -1 LO 0 10 1 10 2 10 -1 10 0 10 I 10 2 (Hz) AMPLIFICATION, LIMERICK, M2P1Kl 1 CORNER: PAGE 1 OF (Hz) Figure 2.3.6-2 Example suite of amplification factors (5% of critical damping pseudo absolute acceleration spectra) developed for the mean base-case profile (P1), linear analyses (model M2), and base-case kappa at eleven loading levels of hard rock median peak acceleration values from 0.01g to 1.50g. M 6.5 and single-corner source model (Reference

3) Limerick Generating Station Report Number. EXLNLlM065-PR-001.

Revision 0 Correspondence No.: RS-14-069 2-13 c ... o g ...., rO u ;;0b-____

1M 0 a... E a: -I INPUT 110Tl(ll O.5IlG I lJilUT MOTI(lI O.7SG o e

a... E a: i lJilUT 110Tl(ll 1. OOG i' IJilUT noTI(lI 1.2SG e 9

c ... og ..., to U ..... 0

• 0 a... e a: -I -_"10-. INPUT MOTI(lI I.SOG e Limerick Generating Station 10 -] LO 0 10 1 10 2 F reguency (Hz) AMPLIFICATION, LIMERICK, M2PIKl M 6.5/ 1 CORNER; PAGE c OF c Figure 2.3.6-2 continued Report Number. EXLNLlM065-PR-001.

Revision 0 Correspondence No.: RS-14-069 2-14

2.3.7 Control

Point Seismic Hazard Curves The procedure to develop probabilistic site-specific control point hazard curves used in the present analysis follows the methodology described in Section 8-6.0 of the SPID (Reference 3). This procedure, referred to as Method 3, computes a site-specific control point hazard curve for a broad range of spectral accelerations given the site-specific bedrock hazard curve and site-specific estimates of soil or soft-rock response and associated uncertainties.

This process is repeated for each of the seven spectral frequencies for which ground motion equations are available. The dynamic response of the materials below the control point was represented by the frequency and dependent amplification functions (median values and standard deviations) developed and described in the previous section. The resulting control point mean hazard curves for LGS are shown in Figure 2.3.7-1 for the seven spectral frequencies for which ground motion equations are defined. Tabulated values of mean and fractile seismic hazard curves and site response amplification functions are provided in Appendix A. III u c III "0 III III III ... 0 > u C III :s C' III .:: iii :s c c <t Total Mean Soil Hazard by Spectral Frequency at Limerick 1E-2 I'. """"""""'" 1E-3 -1E-4 1E-5 1E-6 1E-7 0.01 " -. " I' , ;:"0". cs... ....... "--:0;;;;: '),'.' " "" '" , , , ,,'-. "-" I '" " " , I' " " "-i'" "\. \ .. 1 Spectral acceleration (g) -25Hz -10Hz -5Hz -PGA -2.5 Hz -1Hz -0.5 Hz 10 Figure 2.3.7-1 Control point mean hazard curves for spectral frequencies of 0.5, 1,2.5 , 5, 10, 25 and 100 Hz (PGA) at LGS (5% of critical damping) Limerick Generating Stat i on Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 2-15

2.4 CONTROL

POINT RESPONSE SPECTRA (UHRS & GMRS) The control point hazard curves described in Section 2.3.7 have been used to develop geometric mean horizontal uniform hazard response spectra (UHRS) and the GMRS. The UHRS were obtained through linear interpolation in log-log space to estimate the spectral acceleration at each spectral frequency for the 1 E-4 and 1 E-5 per year hazard levels. The 1 E-4 and 1 E-5 UHRS, along with a design factor (OF) are used to compute the GMRS at the control point using the criteria in NRC Reg. Guide 1.208 (Reference 15). The GMRS developed herein represents an alternative seismic demand determined for LGS using recently developed techniques. Table 2.4-1 shows the UHRS and GMRS accelerations for a range of spectral frequencies. Figure 2.4-1 shows the UHRS and GMRS at the control point. Mean Soil UHRS and GMRS at Limerick 0.8 11.0 -l E-S UHRS c' 0 ',p 0.6 I! QI Qj U U "' '! 0.4 -GMRS I v' 1\1' i' I

-lE-4UHRS u QI Q. III 0.2 Spectral frequency, Hz Figure 2.4-1 Plots of 1 E-4 and 1 E-5 UHRS and GMRS at control point for LGS (5% of critical damping response spectra) Li me ri ck Generat i ng Stat i on Report Numbe r. EX L NLlM065-PR-001 , Revision 0 Correspondence No.: RS-14-069 2-16 Table 2.4-1 UHRS and GMRS at control point for LGS (5% of critical damping response spectra) Freq (Hz) 1 E-4 UHRS (g) 100 1.26E-01 90 1.26E-01 80 1.27E-01 70 1.28E-01 60 1.31 E-01 50 1.40E-01 40 1.56E-01 35 1.67E-01 30 1.81 E-01 25 1.99E-01 20 2.18E-01 15 2.36E-01 12.5 2.43E-01 10 2.49E-01 9 2.47E-01 8 2.44E-01 7 2.36E-01 6 2.24E-01 5 2.09E-01 4 1.75E-01 3.5 1.56E-01 3 1.35E-01 2.5 1.12E-01 2 9.97E-02 1.5 8.52E-02 1.25 7.27E-02 1 6.26E-02 0.9 5.73E-02 0.8 5.09E-02 0.7 4.62E-02 0.6 4.03E-02 0.5 3.31E-02 0.4 2.64E-02 0.35 2.31E-02 0.3 1.98E-02 0.25 1.65E-02 0.2 1.32E-02 0.15 9.92E-03 0.125 8.27E-03 0.1 6.61E-03 Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 1 E-5 UHRS (g) GMRS (g) 4.08E-01 1.93E-01 4.13E-01 1.95E-01 4.19E-01 1.98E-01 4.28E-01 2.02E-01 4.46E-01 2.10E-01 4.88E-01 2.28E-01 5.55E-01 2.58E-01 6.01 E-01 2.79E-01 6.60E-01 3.06E-01 7.32E-01 3.39E-01 7.81 E-01 3.63E-01 8.12E-01 3.81E-01 8.20E-01 3.86E-01 8.13E-01 3.85E-01 8.04E-01 3.81 E-01 7.88E-01 3.74E-01 7.61 E-01 3.61 E-01 7.15E-01 3.40E-01 6.61 E-01 3.15E-01 5.55E-01 2.64E-01 4.93E-01 2.35E-01 4.25E-01 2.03E-01 3.54E-01 1.69E-01 3.11 E-01 1.49E-01 2.61 E-01 1.25E-01 2.21 E-01 1.06E-01 1.87E-01 9.02E-02 1.70E-01 8.21E-02 1.50E-01 7.26E-02 1.35E-01 6.52E-02 1.16E-01 5.63E-02 9.34E-02 4.55E-02 7.47E-02 3.64E-02 6.54E-02 3.19E-02 5.60E-02 2.73E-02 4.67E-02 2.28E-02 3.74E-02 1.82E-02 2.80E-02 1.37E-02 2.33E-02 1.14E-02 1.87E-02 9.10E-03 2-17 3 Plant Design Basis Ground Motion The design basis for LGS is identified in the Updated Final Safety Analysis Report (Reference 9). The current licensing basis SSE for LGS is based upon an evaluation of the maximum earthquake potential considering the regional and local geology, seismology, tectonic history and specific characteristics of local subsurface material.

The response spectrum is based on data developed from records of previous earthquake activity and represents an envelope of motion expected at a sound rock site from a nearby earthquake (Reference 9, Section 3.7.1.1). Considering the historic seismicity of the site region, the maximum potential earthquake might either be an intensity VII event along the Fall Zone at its closest approach to the site or an intensity VI event very near the site. Because of the uncertainties involved in associating regional activity with specific structures, the maximum potential earthquake is specified as being equivalent to the intensity VII 1871 Wilmington, Delaware earthquake occurring near the site (Reference 9, Section 2.5.2.4).

3.1 SSE DESCRIPTION OF SPECTRAL SHAPE The SSE is defined in terms of a PGA and a design response spectrum.

Considering a site design intensity of VII, the maximum horizontal ground acceleration is conservatively defined with 15% of gravity (0.15g) as the anchor point for the SSE (Reference 9, Section 2.5.2.6).

The site design response spectrum for the SSE has a Newmark-type spectral shape (Reference 9, Figure' 3.7-2). The horizontal SSE (5% of critical damping) for LGS is shown below in Figure 3.1-1. Table 3.1-1 shows the spectral acceleration values as a function of frequency for the horizontal SSE (5% of critical damping).

The SSE acceleration values are based upon a Newmark-type spectrum with a peak velocity to peak acceleration ratio of 36 in.lsec.lg and a peak ground displacement to peak acceleration ratio at 12 in.lg, which matches Figure 3.7-2 of the UFSAR (Reference 9). Table 3.1-1 Horizontal SSE for LGS (5% of critical damping response spectrum)

Frequency (Hz) 0.55 2 10 33 100/PGA Limerick Generating Station Report Number: EXLNLlM065-PR-001 , Revision 0 Correspondence No.: RS-14-069 Spectral Acceleration (g) 0.11 0.41 0.41 0.15 0.15 3-1 Horizontal SSE for Limerick 0045 0040 0.35 0.30 tI.D C 0 0.25 ';:l III ... CII 'ii 0.20 u u III iU ... 0.15 1:: CII Q. 11'1 0.10 0.05 I II J \ I \ I I I \ V , I I I \ II I I -0.00 -0.1 1 10 100 Spectral frequency, Hz Figure 3.1-1 Horizontal SSE for LGS (5% of critical damping response spectrum)

3.2 CONTROL

POINT ELEVATION The LGS UFSAR (Reference

9) does not define an SSE control point. Bedrock at the site is overlain by up to 40 feet of residual soil derived from the bedrock by weathering (Reference 9, Section 2.5.1.2.6). All Category I rock foundations were excavated to unweathered bedrock (Reference 9 , Section 2.5.1.2.7.1).

Since LGS is a rock site and all primary safety related structures are founded on bedrock, the SSE control point elevation is taken to be at the top of the rock surface (Triasssic Brunswick lithofacies) at EI. 204 ft. MSL. This definition of the control point is consistent with the approach described in the SPID (Reference 3, Section 2.4.2). Lim eri ck Generat i ng Sta ti on Report Numbe r. EXLNLlM065-PR-001. Rev i sion 0 Co rr espondence No.: RS-14-069 3-2 4 Screening Evaluation Following completion of the seismic hazard reevaluation, as requested in the 50.54(f) letter (Reference 1), a screening evaluation is performed in accordance with the SPI D Section 3 (Reference 3). The horizontal GMRS determined from the hazard reevaluation is used to characterize the amplitude of the alternative seismic hazard at each of the nuclear power plant sites. The screening evaluation is based upon a comparison of the GMRS with the established plant-level seismic capacity (either the SSE or IPEEE HCLPF Spectrum (IHS), where IPEEE is defined as Individual Plant Examination of External Events and HCLPF is defined as high-confidence-of-Iow-probability-of-failure), in accordance with the SPID (Reference 3). For LGS, the plant-level seismic capacity is based on the SSE. 4.1 RISK EVALUATION SCREENING (1 TO 10 Hz) In the frequency range of 1 to 10 Hz, the SSE for LGS envelopes the GMRS. According to the SPID Section 3.2 (Reference 3), LGS screens out from further risk evaluations, and a seismic risk assessment (SPRA or SMA) is not needed. Additionally, LGS screens out of the ESEP interim action per the "Augmented Approach" guidance document, Section 2.2 (Reference 4). 4.2 HIGH FREQUENCY SCREENING

(> 10Hz) In the frequency range above 10Hz, the LGS SSE spectral acceleration exceeds that of the GMRS up to a spectral frequency of approximately 10.7 Hz. However, in the frequency range above approximately 10.7 Hz, the GMRS envelopes the SSE for LGS. Therefore, a high frequency confirmation is needed for LGS in accordance with the SPID guidance, Sections 3.2 and 3.4 (Reference 3). As summarized in the SPID (Reference 3), EPRI Report NP-7498 (Reference

24) concludes that high-frequency vibration is not damaging, in general, to components with strain-or stress-based failure modes. However, components, such as relays, subject to electrical functionality failure modes have unknown acceleration sensitivity for frequencies above 16 Hz. EPRI Report 1015108 (Reference

25) provides evidence that supports the conclusion that high-frequency motions are not damaging to the majority of nuclear plant components, excluding relays and other electrical devices whose output signals may be affected by high-frequency vibration.

The types of SSCs which may be affected by high frequency ground motions include relays, co ntactors , and similar devices subject to electrical functionality failure modes such as inadvertent change of state, contact chatter, or change in output point. EPRI has established a test program to develop data to support high frequency confirmation as described in the SPID, Sections 3.4.2 and 3.4.3 (Reference 3). The test program, which will evaluate the typical component types listed in Table 3-3 of the SPID Limerick Generating Station Report Number. EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 4-1 (Reference 3), uses accelerations or spectral levels intended to be sufficiently high to address the high-frequency in-structure and in-cabinet responses of various plants. Reports from the EPRI high frequency testing program will serve as critical input to the LGS high frequency confirmation.

Example component types reproduced from Table 3-3 of the SPID (Reference

3) are:

• Electro-mechanical relays

• Circuit breakers

• Control switches

• Process switches and sensors

• Electro-mechanical contactors

• Auxiliary contacts

• Transfer switches

• Potentiometers

4.3 SPENT

FUEL POOL EVALUATION SCREENING (1 TO 10 Hz) LGS is screened from performance of a full seismic risk assessment based on the screening criteria for GMRS comparison to the SSE in the SPID Section 3.2 (Reference 3). Therefore, a spent fuel pool evaluation is not needed for LGS in accordance with the SPID, Section 7 (Reference 3). Limerick Generating Station Report Number: EXLNLlM065-PR-001.

Revision 0 Correspondence No.: RS-14-069 4-2 5 Interim Actions Based on the screening results as described in Section 4 of this report , the SSE envelopes the GMRS in the frequency range of 1 to 10Hz for LGS. Therefore , LGS screens out of a seismic risk evaluation. Additionally, LGS screens out of the ESEP interim action per the "Augmented Approach" guidance document, Section 2.2 (Reference 4). 5.1 EXPEDITED SEISMIC EVALUATION PROCESS Based on the screening results, LGS screens out of the ESEP interim action per the "Augmented Approach" guidance document, Section 2.2 (Reference 4). 5.2 INTERIM EVALUATION OF SEISMIC HAZARD Consistent with the NRC letter dated February 20, 2014 (Reference 12), the seismic hazard reevaluations presented herein are distinct from the current design and licensing bases of LGS. Therefore, the results do not call into question the operability or functionality of SSCs and are not reportable pursuant to 10CFR50.72 , "Immediate notification requirements for operating nuclear power reactors" (Reference 2, Section 50.72) and 1 OCFR50. 73, "Licensee event report system" (Reference 2, Section 50.73). The NRC letter also requests that licensees provide an interim evaluation or actions to demonstrate that the plant can cope with the reevaluated hazard while the expedited approach and risk evaluations are conducted.

In response to that request, the NElletter dated March 12, 2014 (Reference

26) provides seismic core damage risk estimates using the updated seismic hazards for the operating nuclear plants in the CEUS. These risk estimates continue to support the following conclusions of the NRC GI-199 Safety/Risk Assessment (Reference 18): "Overall seismic core damage risk estimates are consistent with the Commission's Safety Goal Policy Statement because they are within the subsidiary objective of 10-4/year for core damage frequency. The GI-199 Safety/Risk Assessment, based in part on information from the U.S. Nuclear Regulatory Commission's (NRC's) Individual Plant Examination of External Events (IPEEE) program, indicates that no concern exists regarding adequate protection and that the current seismic design of operating reactors provides a safety margin to withstand potential earthquakes exceeding the original design basis." LGS is included in the March 12, 2014 risk estimates (Reference 26). Using the methodology described in the NEI letter, the seismic core damage risk estimates for all plants were shown to be below 1 E-4/year; thus, the above conclusions apply. Limerick Generating Sta ti on Report Number: EXLNLlM065

-PR-001 , Revision 0 Correspondence No.: RS-1 4-069 5-1

5.3 SEISMIC

WALKDOWN INSIGHTS In response to NTTF 2.3, the 50.54(f) letter (Reference

1) also requested licensees to perform seismic walkdowns in order to, in the context of seismic response:

1) verify that the current plant configuration is consistent with the licensing basis; 2) verify the adequacy of current strategies, monitoring, and maintenance programs; and 3) identify degraded, nonconforming, or unanalyzed conditions.

Exelon committed to and performed seismic walkdowns in accordance with the seismic walkdown guidance (Reference

27) as initially documented and supplemented in Exelon Correspondence Numbers RS-12-171 and RS-13-138 (References 11 and 29) respectively.

The remaining walkdowns for initially inaccessible equipment are scheduled to be completed during the next Unit 1 Refueling Outage, 1 R 15, or during the next scheduled system outage window, whichever is applicable. The results will be reported to the NRC after completion of the follow-on walkdowns.

Based on the successful completion of seismic walkdowns for all components to date in response to NTTF 2.3, and the lack of adverse seismic conditions identified, Exelon has directly concluded that the LGS current plant configuration is consistent with the plant licensing basis and can safely shut down the reactor and maintain containment integrity following the design basis SSE event. Additionally, the findings of the seismic walkdown program indirectly verify that the current LGS strategies, monitoring, and maintenance programs are adequate for ensuring seismic safety consistent with the licensing basis. Plant vulnerabilities and commitments identified in the LGS IPEEE (Reference

10) were reviewed as part of the NTTF 2.3 seismic walkdowns (References 11 and 29). The seismic walkdown reports confirmed that there are no outstanding IPEEE vulnerabilities or commitments, and all previously identified IPEEE vulnerabilities and commitments have been resolved (References 11 and 29). 5.4 BEYOND-DESIGN-BASIS SEISMIC INSIGHTS An evaluation of beyond-design-basis ground motions was performed for LGS as part of the IPEEE program. The LGS IPEEE program demonstrated plant-level seismic capacity, which can be expressed in terms of a HCLPF. This plant-level seismic capacity is defined in Section 3.3.2 of the SPID (Reference

3) as the IHS. The LGS IPEEE seismic evaluation was initially submitted as a reduced scope SMA (Reference 10). Subsequent to the IPEEE submittal, LGS responded to a series of Requests for Additional Information (RAI) and provided additional information that justified the LGS IPEEE SMA as achieving the intent of a focused-scope EPRI SMA anchored at 0.3g PGA (References 19, 20 and 21). The IHS for LGS is defined by the median-shaped NUREG/CR-0098 spectra for rock sites per LGS IPEEE seismic demand analysis (Reference 22). As a result of the LGS IPEEE seismic evaluations, plant processes for seismic housekeeping were made to enhance the reliability and safety of the plant. There are no outstanding IPEEE vulnerabilities or commitments and all previously identified IPEEE vulnerabilities and commitments have been resolved (Reference 11). The results of the LGS IPEEE showed there were no vulnerabilities to severe accident risk from external events, including seismic events (Reference 10). Based on the results of the IPEEE program for LGS, it may be qualitatively concluded that the plant has significant seismic margin beyond the design basis (Reference 28, Section 2.3.4) as evidenced by a comparison between the site SSE and the IHS in Figure 5.4-1. Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 5-2 The IHS for LGS bounds the GMRS over all frequencies and is provided for context of demonstrating beyond-design-basis seismic margin capacity; however , the IHS is not used for the NTTF 2.1: Seismic screening evaluation.

The horizontal IHS (5% of critical damping) is shown below in Table 5.4-1 and plotted in Figure 5.4-1. Table 5.4-1 HorizontallHS for LGS (5% of critical damping response spectrum) 0.700 0.600 0.500 lID C :8 0.400 l! CI.l u 0.300 III l! tl :g, 0.200 1/1 0.100 0.000 .-II1II' 0.1 Frequency (Hz) Spectral Acceleration (g) 0.34 0.10 2.2 0.63 8 0.63 33 0.30 100/PGA 0.30 HorizontallHS and SSE for Limerick i Ii I \ I \ I I \ ,I I \ \ -SSE )1 1 \ \. ---IHS , I ., I

• 1 10 100 Spectral frequency, Hz Figure 5.4-1 HorizontallHS and SSE for LGS (5% of critical damping response spectra) Lime ri ck Genera ti ng Stat i on Report Numbe r. EXLNLlM065

-PR-001. Rev i s i on 0 Correspondence No.: RS-14-069 5-3 6 Conclusions In accordance with the 50.54(f) letter (Reference 1), a seismic hazard and screening evaluation was performed for LGS. This evaluation followed the SPID guidance (Reference

3) in order to develop a site GMRS for the purpose of screening the plant in accordance with the SPID. The new GMRS does not constitute a change in the plant design or licensing basis as described in the NRC letter dated February 20, 2014 (Reference 12). The screening evaluation comparison demonstrates that for LGS the SSE envelopes the GMRS in the frequency range of 1 to 10Hz. For this reason, LGS screens out of seismic risk assessments (SPRAISMA) and spent fuel pool integrity evaluation per the SPID, Sections 3.2 and 7 (Reference

3) in response to NTTF 2.1: Seismic. Additionally, LGS screens out of the ESEP interim action per the "Augmented Approach" guidance document, Section 2.2 (Reference 4). However, due to the GMRS exceeding the SSE in the frequency range above 10Hz, a high frequency confirmation is needed for LGS in accordance with the SPID Sections 3.2 and 3.4 (Reference 3). Actions to address NTTF 2.1: Seismic for CEUS nuclear plants will be performed in accordance with the schedule provided in the April 9, 2013 letter from the industry to the NRC (Reference 5), as agreed to by the NRC in the May 7, 2013 letter to the industry (Reference 23). Limerick Generating Station 6-1 Report Number: EXLNLlM065-PR-001 , Rev i sion 0 Correspondence No.: RS-14-069 7 References

1. NRC (E. Leeds and M. Johnson) Letter to All Power Reactor Licensees et aI., Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated March 12, 2012. 2. Title 10 Code of Federal Regulations Part 50, Domestic Licensing of Production and Utilization Facilities. 3. EPRI 1025287, Seismic Evaluation Guidance:

Screening, Prioritization and Implementation Details (SPID) for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1: Seismic, Palo Alto, CA, February 2013. 4. EPRI 3002000704, Seismic Evaluation Guidance:

Augmented Approach for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1: Seismic, Palo Alto, CA, May 2013. 5. NEI Letter (A. R. Pietrangelo) to the NRC, Proposed Path Forward for NTTF Recommendation 2.1: Seismic Reevaluations, dated April 9, 2013. 6. EPRI 1021097 (NUREG-2115), Central and Eastern United States Seismic Source Characterization for Nuclear Facilities, Palo Alto, CA, January 2012. 7. EPRI 3002000717, EPRI (2004, 2006) Ground-Motion Model (GMM) Review Project, Palo Alto, CA, June 2013. 8. Silva, W.J., N. Abrahamson, G. Toro and C. Costantino, "Description and validation of the stochastic ground motion model", Report Submitted to Brookhaven National Laboratory, Associated Universities, Inc. Upton, New York 11973, Contract No. 770573, 1997. 9. Exelon Generation Company, Limerick Generating Station, Units 1 and 2, Updated Final Safety Analysis Report (UFSAR), Revision 16. 10. PECO Energy Company, Limerick Generating Station, Units 1 and 2, Individual Plant Examination for External Events, June 1995. 11. Exelon Generation Company letter to the NRC, Exelon Generation Company, LLC's 1BO-day Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding the Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, RS-12-171, dated November 19,2012. Limerick Generating Station 7-1 Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069

12. NRC (E. Leeds) Letter to All Power Reactor Licensees et aI., Supplemental Information Related to Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Seismic Hazard Reevaluations for Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated February 20, 2014. 13. Exelon Generation Company letter to the NRC, Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding the Seismic Aspects of Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, RS-13-1 02, dated April 29, 2013. 14. SGH Report No. 128018-R-01, Revision 1, Review of Existing Site Response Data for the Exelon Nuclear Fleet, July 17 , 2012. 15. NRC Regulatory Guide 1.208, A performance-based approach to define the specific earthquake ground motion , 2007. 16. EPRI RSM-112013-024, Limerick Seismic Hazard and Screening Report, dated November 27,2013. 17. Title 10 Code of Federal Regulations Part 100, Reactor Site Criteria.

18. NRC Memorandum (from P. Hiland to B. Sheron), ML 100270582, "Safety/Risk Assessment Results for Generic Issue 199, Implications of Updated Probabilistic Seismic Hazard Estimates in Central and Eastern United States on Existing Plants," dated September 2, 2010. 19. PECD Energy Company letter to the NRC, Limerick Generating Station, Units 1 and 2 Response to Request for Additional Information Regarding Review of Individual Plant Examination of External Events, dated June 28, 1996. 20. PECD Energy Company letter to the NRC, Limerick Generating Station, Units 1 and 2 Response to Request for Additional Information Regarding Review of Individual Plant Examination of External Events , dated July 24, 1997. 21. PECD Energy Company letter to the NRC, Limerick Generating Station, Units 1 and 2 Response to Request for Additional Information Regarding Review of Individual Plant Examination of External Events , dated February 17, 1999. 22. Exelon Calculation LS-0178, IPEEE-SMA Seismic Demand for LGS , Rev. O. 23. NRC (E. Leeds) Letter to NEI (J. Pollock), ML 131 06A331, 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, II as an Acceptable Alternative to the March 12, 2012, Information Request for Seismic Reevaluations , dated May 7, 2013. 24. EPRI NP-7498, Industry Approach to Seismic Severe Accident Policy Implementation, Palo Alto, CA, November 1991. Limerick Generat i ng Stat i on Report Number: EXLNLlM065

• PR*001 , Revision 0 Correspondence No.: RS*14*069 7-2

25. EPRI 1015108, Program on Technology Innovation:

The Effects of High-Frequency Ground Motion on Structures, Components, and Equipment in Nuclear Power Plants, Palo Alto, CA, June 2007. 26. NEI Letter (A. R. Pietrangelo) to the NRC, Seismic Risk Evaluations for Plants in the Central and Eastern United States, dated March 12,2014. 27. EPRI 1025286, Seismic Walkdown Guidance for Resolution of Fukushima Term Task Force Recommendation 2.3: Seismic, Palo Alto, CA, June 2012. 28. NUREG-1742, Volume 1, Perspectives Gained from the Individual Plant Examination of External Events (IPEEE) Program, April 2002. 29. Exelon Generation Company letter to the NRC, Supplemental Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding the Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, RS-13-138, dated October 7, 2013. Limerick Generating Station Report Number: EXLNLlM065-PR-001 , Revision 0 Correspondence No.: RS-14-069 7-3 A Additional Tables Table A-1a Mean and fractile seismic hazard curves for PGA at LGS 5% of critical damping , AMPS(Q) MEAN 0.05 O.OOOS 3.7SE-02 1.S7E-02 0.001 2.68E-02 1.01E-02 O.OOS 7.40E-03 3.28E-03 0.01 3.78E-03 1.S7E-03 0.01S 2.3SE-03 B.8SE-04 0.03 S.SOE-04 2.S3E-04 O.OS 4.47E-04 8.60E-OS 0.07S 2.37E-04 3.68E-OS 0.1 1.48E-04 1.S8E-OS 0.1S 7.34E-OS 8.00E-06 0.3 1.SSE-OS 1.2SE-06 O.S 6.44E-06 2.4SE-07 0.7S 2.44E-06 6.0SE-08 1. 1.1SE-06 1.S8E-08 1.S 3.63E-07 3.47E-OS 3. 3.68E-OB 1.67E-10 S. S.02E-OS 6.64E-11 7.S B.3SE-10 S.OSE-11 10. 2.0SE-10 S.OSE-11 Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 0.16 0.50 0.84 0.95 2.S6E-02 3.84E-02 4.70E-02 S.3SE-02 1.SSE-02 2.64E-02 3.S7E-02 4.13E-02 4.70E-03 6.73E-03 S.S1E-03 1.S1 E-02 2.22E-03 3.42E-03 4.S0E-03 8.47E-03 1.2SE-03 2.07E-03 3.23E-03 S.7SE-03 3.S0E-04 7.34E-04 1.44E-03 2.S7E-03 1.46E-04 3.1SE-04 7.23E-04 1.31 E-03 6.S3E-OS 1.60E-04 3.S0E-04 7. 13E-04 4.01E-OS S.S3E-OS 2.42E-04 4.S0E-04 1.87E-OS 4.83E-OS 1.20E-04 2.2SE-04 4.07E-06 1.23E-OS 3.23E-OS S.S1E-OS 1.0BE-06 3.B4E-06 1.0BE-OS 2.07E-OS 3.0SE-07 1.34E-06 4.1SE-06 B.3SE-06 1.16E-07 S.7SE-07 1.S8E-06 4. 1 SE-06 2.2SE-OB 1.4SE-07 6.26E-07 1.42E-06 B.47E-10 B.S8E-OS S.83E-OB 1.S7E-07 1.1BE-10 7.66E-10 6.S3E-OS 2.1SE-08 B.3SE-11 1.44E-10 1.04E-OS 3.68E-OS 6.0SE-11 1.11E-10 2.80E-10 S.S3E-10 A-1 Table A-1 b Mean and fractile seismic hazard curves for 25 Hz at LGS 5% of critical damping I AMPS(g) MEAN 0.05 0.16 0.50 0.84 0.95 0.0005 4.05E-02 2.04E-02 3.37E-02 4.07E-02 4.83E-02 5.42E-02 0.001 3.02E-02 1.34E-02 2.32E-02 2.9SE-02 3.84E-02 4.50E-02 0.005 9.88E-03 4.70E-03 S.54E-03 9.11E-03 1.23E-02 1.98E-02 0.01 5.59E-03 2.S4E-03 3.57E-03 5.12E-03 S.93E-03 1.1SE-02 0.015 3.79E-03 1.S7E-03 2.29E-03 3.47E-03 4.90E-03 7.77E-03 0.03 1.SSE-03 5.SSE-04 8.47E-04 1.4SE-03 2.39E-03 3.47E-03 0.05 8.14E-04 2.13E-04 3.47E-04 S.73E-04 1.23E-03 1.90E-03 0.075 4.49E-04 9.79E-05 1.S9E-04 3.52E-04 7.03E-04 1.13E-03 0.1 2.92E-04 5.58E-05 1.02E-04 2.25E-04 4.S3E-04 7.55E-04 0.15 1.58E-04 2.72E-05 5.20E-05 1.20E-04 2.53E-04 4.19E-04 0.3 5.18E-05 7.03E-OS 1.S2E-05 3.95E-05 8.47E-05 1.38E-04 0.5 2.09E-05 2.19E-OS S.09E-OS 1.S0E-05 3.47E-05 5.SSE-05 0.75 9.54E-OS 7.55E-07 2.49E-OS 7.23E-OS 1.S4E-05 2.S4E-05 1. 5.22E-OS 3.37E-07 1.25E-OS 3.90E-OS 9.11E-OS 1.4SE-05 1.5 2.07E-OS 9.37E-08 4.31E-07 1.4SE-OS 3.S8E-OS S.09E-06 3. 3.31E-07 7.89E-09 4.70E-08 2.01E-07 5.91E-07 1.11E-06 5. S.83E-08 1.01 E-09 S.2SE-09 3.42E-08 1.18E-07 2.S0E-07 7.5 1.S8E-08 2.13E-10 1.08E-09 S.83E-09 2.84E-08 7.03E-08 10. 5.74E-09 1.13E-10 3.09E-10 1.95E-09 9.24E-09 2.57E-08 Table A-1c Mean and fractile seismic hazard curves for 10 Hz at LGS 5% of critical damping I AMPS(Q) MEAN 0.05 0.0005 4.S1E-02 3.33E-02 0.001 3.70E-02 2.29E-02 0.005 1.28E-02 S.45E-03 0.01 S.88E-03 3.47E-03 0.015 4.SSE-03 2.25E-03 0.03 2.21E-03 9.37E-04 0.05 1.17E-03 4.19E-04 0.075 S.S9E-04 2.01E-04 0.1 4.40E-04 1.13E-04 0.15 2.35E-04 4.83E-05 0.3 7.27E-05 1.02E-05 0.5 2.77E-05 2.72E-OS 0.75 1.20E-05 7.89E-07 1. S.33E-OS 2.9SE-07 1.5 2.42E-OS S.2SE-08 3. 3.75E-07 3.01E-09 5. 7.73E-08 3.05E-10 7.5 1.90E-08 1.11 E-10 10. S.4SE-09 8.47E-11 Limerick Generating Station Report Number: EXLNLlM065-PR-001 , Rev i s i on 0 Correspondence No.: RS-14-069 0.16 0.50 0.84 0.95 3.95E-02 4.5SE-02 5.35E-02 5.91E-02 3.01E-02 3.S8E-02 4.43E-02 5.05E-02 8.85E-03 1.21 E-02 1.S4E-02 2.1SE-02 4.S3E-03 S.54E-03 8.85E-03 1.23E-02 3.05E-03 4.37E-03 S.00E-03 8.47E-03 1.31 E-03 2.04E-03 3.01E-03 4.07E-03 S.17E-04 1.05E-03 1.S9E-03 2.32E-03 3.14E-04 5.83E-04 1.01 E-03 1.44E-03 1.87E-04 3.S8E-04 S.83E-04 9.93E-04 8.85E-05 1.90E-04 3.79E-04 5.SSE-04 2.19E-05 5.58E-05 1.21E-04 1.92E-04 S.93E-OS 1.98E-05 4.77E-05 7.89E-05 2.39E-OS 8.00E-OS 2.13E-05 3.S3E-05 1.04E-OS 3.95E-OS 1.15E-05 2.04E-05 2.80E-07 1.34E-OS 4.50E-OS 8.23E-OS 2.22E-08 1.55E-07 7.03E-07 1.4SE-OS 2.49E-09 2.25E-08 1.38E-07 3.28E-07 4.01E-10 3.90E-09 3.14E-08 8.47E-08 1.4SE-10 1.05E-09 9.93E-09 2.92E-08 A-2 Table A-1d Mean and fractile seismic hazard curves for 5 Hz at LGS 5% of critical damping , AMPS(g) MEAN 0.05 0.16 0.50 0.84 0.95 O.OOOS 4.BSE-02 3.6BE-02 4.19E-02 4.77E-02 S.SBE-02 6.17E-02 0.001 4.10E-02 2.64E-02 3.2BE-02 4.13E-02 4.90E-02 S.SOE-02 0.005 1.S2E-02 7.13E-03 1.04E-02 1.46E-02 2.04E-02 2.42E-02 0.01 7.62E-03 3.S7E-03 4.9BE-03 7.23E-03 1.04E-02 1.2SE-02 0.015 4.B3E-03 2.29E-03 3.14E-03 4.63E-03 6.S4E-03 B.12E-03 0.03 2.0SE-03 9.24E-04 1.27E-03 1.9SE-03 2.76E-03 3.63E-03 0.05 1.01 E-03 3.9SE-04 S.66E-04 9.37E-04 1.42E-03 1.90E-03 0.075 S.S4E-04 1.B7E-04 2.B4E-04 4.9BE-04 B.12E-04 1.10E-03 0.1 3.S3E-04 1.0SE-04 1.67E-04 3.09E-04 S.3SE-04 7.34E-04 0.1S 1.B1 E-04 4.S6E-OS 7.66E-OS 1.S3E-04 2.B4E-04 4.01E-04 0.3 S.20E-OS 9.37E-06 1.B7E-OS 4.2SE-OS B.47E-OS 1.27E-04 0.5 1.B6E-OS 2.46E-06 S.7SE-06 1.46E-OS 3.14E-OS 4.B3E-OS 0.7S 7.S6E-06 7.03E-07 1.9SE-06 S.SOE-06 1.29E-OS 2.13E-OS 1. 3.BOE-06 2.60E-07 B.12E-07 2.S7E-06 6.64E-06 1.1SE-OS 1.S 1.3SE-06 4.B3E-OB 1.90E-07 B.00E-07 2.46E-06 4.S6E-06 3. 1.90E-07 1.42E-09 B.23E-09 7.4SE-OB 3.47E-07 7.66E-07 5. 3.76E-OB 1.29E-10 S.SBE-10 9.S1E-09 6.4SE-OB 1.64E-07 7.S 9.07E-09 6.26E-11 1.1BE-10 1.S1 E-09 1.40E-OB 4.19E-OB 10. 3.04E-09 S.42E-11 1.02E-10 4.13E-10 4.2SE-09 1.42E-OB Table A-1e Mean and fractile seismic hazard curves for 2.5 Hz at LGS, 5% of critical damping AMPS(g) MEAN 0.05 O.OOOS 4.61E-02 3.42E-02 0.001 3.72E-02 2.3SE-02 0.005 1.20E-02 S.SOE-03 0.01 S.30E-03 2.29E-03 0.015 3.02E-03 1.2SE-03 0.03 1.03E-03 3.B4E-04 O.OS 4.34E-04 1.3BE-04 0.07S 2.12E-04 S.7SE-OS 0.1 1.2SE-04 2.92E-OS 0.15 S.7BE-OS 1.10E-OS 0.3 1.43E-OS 1.69E-06 O.S 4.72E-06 3.47E-07 0.7S 1.B3E-06 B.3SE-OB 1. B.96E-07 2.76E-OB 1.S 3.0SE-07 S.OSE-09 3. 3.B4E-OB 2.3SE-10 S. 6.73E-09 9.79E-11 7.5 1.46E-09 S.3SE-11 10. 4.S1 E-1 0 S.OSE-11 Limerick Generating Station Report Number. EXLNLlM065-PR-001.

Revision 0 Correspondence No.: RS-14-069 0.16 0.50 0.84 0.95 3.B4E-02 4.S6E-02 S.3SE-02 S.91E-02 2.B4E-02 3.6BE-02 4.S6E-02 S.20E-02 7.66E-03 1.13E-02 1.64E-02 2.01E-02 3.19E-03 4.90E-03 7.4SE-03 9.6SE-03 1.77E-03 2.76E-03 4.2SE-03 S.66E-03 S.SBE-04 9.37E-04 1.49E-03 2.04E-03 2.13E-04 3.B4E-04 6.4SE-04 9.11E-04 9.24E-OS 1.79E-04 3.2BE-04 4.70E-04 S.OSE-OS 1.04E-04 1.9BE-04 2. 92 E-04 2.04E-OS 4.S6E-OS 9.37E-OS 1.46E-04 3.90E-06 1.04E-OS 2.42E-OS 4.07E-OS 1.01 E-06 3.14E-06 B.23E-06 1.46E-OS 2.96E-07 1.10E-06 3.23E-06 6.09E-06 1.13E-07 4.90E-07 1.60E-06 3.19E-06 2.S3E-OB 1.3BE-07 S.42E-07 1.1BE-06 1.21E-09 1.02E-OB 6.26E-OB 1.69E-07 1.49E-10 1.10E-09 9.24E-09 3.14E-OB 1.01E-10 1.9BE-10 1.69E-09 6.64E-09 6.09E-11 1.11E-10 4.90E-10 2.04E-09 A-3 Table A-1f Mean and fractile seismic hazard curves for 1 Hz at LGS 5% of critical damping I AMPS{g) MEAN 0.05 0.16 0.50 0.84 0.95 0.0005 3.5BE-02 1.SBE-02 2.S0E-02 3.S3E-02 4.50E-02 5.12E-02 0.001 2.53E-02 1.20E-02 1.SSE-02 2.4SE-02 3.33E-02 3.S5E-02 0.005 S.74E-03 2.2SE-03 3.SBE-03 S.2SE-03 S.7SE-03 1.27E-02 0.01 2.BSE-03 7.BSE-04 1.32E-03 2.4SE-03 4.37E-03 S.2SE-03 0.015 1.55E-03 3.7SE-04 S.54E-04 1.2SE-03 2.42E-03 3.SBE-03 0.03 4.4SE-04 B.SBE-05 1.S2E-04 3.47E-04 7.23E-04 1.20E-03 0.05 1.S0E-04 2.SBE-05 5.05E-05 1.1SE-04 2.S4E-04 4.43E-04 0.075 S.B5E-05 S.S5E-OS 1.B7E-05 4.70E-05 1.1SE-04 1.SBE-04 0.1 3.73E-05 4.50E-OS S.24E-OS 2.42E-05 S.3SE-05 1.15E-04 0.15 1.5SE-05 1.44E-OS 3.2BE-OS S.51E-OS 2.72E-05 5.27E-05 0.3 3.71E-OS 1.72E-07 5.20E-07 1.S0E-OS S.2SE-OS 1.40E-05 0.5 1.23E-OS 2.BOE-OB 1.11E-07 5.20E-07 2.04E-OS 4.SBE-OS 0.75 4.S1E-07 5.S1E-OS 2.S2E-OB 1.72E-07 B.00E-07 2.10E-OS 1. 2.47E-07 1.B2E-OS 1.02E-OB 7.34E-OB 3.S0E-07 1.10E-OS 1.5 B.BOE-OB 3.52E-10 2.07E-OS 1.S0E-OB 1.2SE-07 4.07E-07 3. 1.23E-OB 1.01E-10 1.S0E-10 1.3SE-OS 1.40E-OB 5.S1E-OB 5. 2.35E-OS 5.35E-11 1.01 E-10 1.S5E-10 2.01E-OS 1.07E-OB 7.5 5.52E-10 5.05E-11 S.OSE-11 1.11E-10 4.13E-10 2.25E-OS 10. 1.B2E-10 5.05E-11 5.S1 E-11 1.11E-10 1.S2E-10 7.13E-10 Table A 1 M -Ig ean an rac I e seismic df fI . h azar d curves or za I 00 cn Ica a 0 5 H t LGS 5°A f lid mping AMPS(g) MEAN 0.05 0.0005 1.SBE-02 1.04E-02 0.001 1.22E-02 5.SSE-03 0.005 2.SBE-03 S.2SE-04 0.01 1.01 E-03 1.S2E-04 0.015 5.00E-04 S.54E-05 0.03 1.24E-04 1.1BE-05 0.05 4.00E-05 2.SSE-OS 0.075 1.S2E-05 B.SBE-07 0.1 B.S1E-OS 3.7SE-07 0.15 3.S4E-OS S.S3E-OB 0.3 B.SSE-07 7.55E-OS 0.5 2.SSE-07 S.51E-10 0.75 1.21 E-07 2.13E-10 1. S.1BE-OB 1.1SE-10 1.5 2.27E-OB S.S5E-11 3. 3.34E-OS 5.05E-11 5. S.S5E-10 5.05E-11 7.5 1.S1E-10 5.05E-11 10. 5.41 E-11 5.05E-11 Limerick Generating Station Report Number: EXLNLlM065-PR

-001, Revision 0 Correspondence No.: RS-14-069 0.16 0.50 0.84 0.95 1.44E-02 1.S2E-02 2.53E-02 3.01E-02 B.23E-03 1.1BE-02 1.S2E-02 2.01E-02 1.15E-03 2.32E-03 4.1SE-03 S.00E-03 3.2BE-04 7.SSE-04 1.SSE-03 2.SBE-03 1.3BE-04 3.52E-04 B.SOE-04 1.4SE-03 2.57E-05 7.45E-05 2.22E-04 4.01E-04 S.73E-OS 2.10E-05 7.45E-05 1.40E-04 2.25E-OS 7.55E-OS 2.SSE-05 S.OSE-05 1.01 E-OS 3.SBE-OS 1.53E-05 3.47E-05 3.14E-07 1.34E-OS S.OOE-OS 1.S2E-05 3.7SE-OB 2.25E-07 1.25E-OS 4.31E-OS 6.45E-OS 5.27E-OB 3.73E-07 1.53E-OS 1.40E-OS 1.4SE-OB 1.32E-07 S.45E-07 4.70E-10 5.42E-OS 5.S1E-OB 3.2BE-07 1.3BE-10 1.25E-OS 1.S7E-OB 1.15E-07 7.23E-11 1.34E-10 1.4SE-OS 1.42E-OB S.OSE-11 1.11E-10 2.42E-10 2.32E-OS 5.05E-11 1.11 E-10 1.13E-10 5.05E-10 5.05E-11 1.01E-10 1.11E-10 2.01E-10 A-4 Median Sigma PGA AF In(AF) 1.00E-02 1.1BE+00 S.61E-02 4.9SE-02 9.12E-01 7.13E-02 9.64E-02 B.24E-01 7.69E-02 1.94E-01 7.S4E-01 B.17E-02 2.92E-01 7.1BE-01 B.39E-02 3.91 E-01 6.94E-01 B.51E-02 4.93E-01 6.77E-01 B.60E-02 7.41E-01 6.46E-01 B.6SE-02 1.01E+00 6.23E-01 B.73E-02 1.2BE+00 6.0SE-01 9.03E-02 1.SSE+00 5.91 E-01 9.04E-02 Median Sigma 2.5 Hz AF In(AF) 2.1BE-02 1.27E+00 7.69E-02 7.0SE-02 1.2SE+OO 7.75E-02 1.1BE-01 1.23E+00 7.B6E-02 2.12E-01 1.22E+00 B.19E-02 3.04E-01 1.21E+00 B.S2E-02 3.94E-01 1.20E+00 B.91E-02 4.B6E-01 1.19E+00 9.34E-02 7.09E-01 1.17E+OO 1.01 E-01 9.47E-01 1.1SE+OO 1.0SE-01 1.19E+00 1.13E+00 1.14E-01 1.43E+00 1.12E+00 1.14E-01 Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 Table A-2 Amolification fl Median Sigma 25 Hz AF In(AF) 1.30E-02 9.B4E-01 6.1SE-02 1.02E-01 6.22E-01 1.14E-01 2.13E-01 S.61 E-01 1.31 E-01 4.43E-01 S.17E-01 1.42E-01 6.76E-01 S.00E-01 1.47E-01 9.09E-01 S.OOE-01 1.50E-01 1.1SE+00 5.00E-01 1.S2E-01 1.73E+00 S.00E-01 1.SSE-01 2.36E+00 S.00E-01 1.S7E-01 3.01E+00 S.00E-01 1.60E-01 3.63E+00 S.00E-01 1.61 E-01 Median Sigma 1 Hz AF In(AF) 1.27E-02 1.6BE+00 1.06E-01 3.43E-02 1.66E+00 1.04E-01 S.S1E-02 1.66E+00 1.03E-01 9.63E-02 1.6SE+00 1.03E-01 1.36E-01 1.6SE+00 1.03E-01 1.75E-01 1.6SE+00 1.02E-01 2.14E-01 1.6SE+00 1.02E-01 3.10E-01 1.6SE+00 1.01 E-01 4.12E-01 1.64E+OO 1.0SE-01 S.1BE-01 1.63E+00 1.23E-01 6.19E-01 1.63E+00 1.26E-01 for LGS. 5% of critical d _.-._. Median Sigma Median Sigma 10 Hz AF In(AF) 5 Hz AF In(AF) 1.90E-02 1.04E+00 9.61E-02 2.09E-02 1.2BE+00 1.12E-01 9.99E-02 9.S3E-01 1.17E-01 B.24E-02 1.24E+00 1.20E-01 1.BSE-01 9.2SE-01 1.22E-01 1.44E-01 1.22E+00 1.23E-01 3.S6E-01 B.92E-01 1.26E-01 2.65E-01 1.20E+00 1.26E-01 S.23E-01 B.69E-01 1.29E-01 3.B4E-01 1.1BE+00 1.27E-01 6.90E-01 B.50E-01 1.31 E-01 5.02E-01 1.16E+OO 1.2BE-01 B.61 E-01 B.3SE-01 1.33E-01 6.22E-01 1.14E+00 1.29E-01 1.27E+OO B.03E-01 1.3SE-01 9.13E-01 1.11E+00 1.30E-01 1.72E+00 7.77E-01 1.36E-01 1.22E+00 1.0BE+00 1.33E-01 2.17E+00 7.SSE-01 1.37E-01 1.S4E+00 1.0SE+00 1.36E-01 2.61E+00 7.37E-01 1.37E-01 1.BSE+00 1.03E+00 1.36E-01 Median Sigma 0.5 Hz AF In(AF) B.2SE-03 1.S9E+00 9.7BE-02 1.96E-02 1.SBE+OO 9.3SE-02 3.02E-02 1.S7E+OO 9.20E-02 S.11E-02 1.SBE+00 9.09E-02 7.10E-02 1.SBE+00 9.0BE-02 9.06E-02 1.S9E+00 9.11 E-02 1.10E-01 1.S9E+00 9.15E-02 1.SBE-01 1.60E+00 9.3BE-02 2.09E-01 1.61E+00 9.9BE-02 2.62E-01 1.61E+OO 1.07E-01 3.12E-01 1.61E+OO 1.0SE-01 A-5 Tables A2-b1 and A2-b2 are tabular versions of the typical amplification factors provided in Figures 2.3.6-1 and 2.3.6-2. Values are provided for two input motion levels at approximately 1 E-4 and 1 E-5 mean annual frequency of exceedance. These tables concentrate on the frequency range of 0.5 Hz to 25 Hz, with values up to 100 Hz included, and a single value at 0.1 Hz included for completeness.

These factors are unverified and are provided for information only. The figures should be considered the governing information. Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 A-6 T bl A2 b1 M d' AF d . f M d I 1 P fil 1 f GAl a e -elan san sigmas or o e I ro Ie I or 2 P evels M1P1K1 Rock PGA=O.194 Freq Soil SA Median (Hz) AF 100.0 0.145 0.745 87.1 0.145 0.728 75.9 0.145 0.699 66.1 0.146 0.645 57.5 0.148 0.557 50.1 0.151 0.472 43.7 0.155 0.411 38.0 0.161 0.388 33.1 0.169 0.385 28.8 0.179 0.408 25.1 0.194 0.437 21.9 0.210 0.497 19.1 0.228 0.547 16.6 0.246 0.614 14.5 0.263 0.687 12.6 0.278 0.746 11.0 0.296 0.813 9.5 0.307 0.882 8.3 0.314 0.978 7.2 0.313 1.042 6.3 0.312 1.105 5.5 0.313 1.158 4.8 0.315 1.190 4.2 0.311 1.213 3.6 0.297 1.190 3.2 0.284 1.208 2.8 0.275 1.235 2.4 0.264 1.280 2.1 0.250 1.333 1.8 0.233 1.393 1.6 0.217 1.494 1.4 0.206 1.648 1.2 0.183 1.659 1.0 0.170 1.712 0.91 0.153 1.692 0.79 0.131 1.604 0.69 0.121 1.654 0.60 0.102 1.611 0.52 0.085 1.572 0.46 0.075 1.659 0.10 0.003 1.618 Limerick Generating Station Report Number: EXLNLlM065-PR-001, Revision 0 Correspondence No.: RS-14-069 Sigma In(AF) 0.081 0.082 0.082 0.084 0.086 0.091 0.098 0.106 0.116 0.127 0.145 0.158 0.166 0.167 0.160 0.155 0.150 0.144 0.131 0.141 0.139 0.140 0.124 0.103 0.102 0.094 0.077 0.075 0.068 0.085 0.091 0.065 0.087 0.109 0.088 0.083 0.074 0.080 0.083 0.099 0.049 M1P1K1 PGA=O.741 Freq Soil SA Median Sigma (Hz) AF In(AF) 100.0 0.426 0.575 0.092 87.1 0.426 0.557 0.093 75.9 0.427 0.528 0.093 66.1 0.429 0.474 0.094 57.5 0.431 0.396 0.095 50.1 0.434 0.327 0.098 43.7 0.441 0.281 0.103 38.0 0.450 0.264 0.109 33.1 0.464 0.262 0.117 28.8 0.482 0.276 0.126 25.1 0.507 0.293 0.140 21.9 0.543 0.334 0.158 19.1 0.584 0.370 0.171 16.6 0.633 0.422 0.176 14.5 0.685 0.485 0.179 12.6 0.731 0.538 0.181 11.0 0.782 0.595 0.186 9.5 0.830 0.668 0.193 8.3 0.868 0.764 0.185 7.2 0.894 0.848 0.169 6.3 0.898 0.913 0.157 5.5 0.899 0.964 0.169 4.8 0.925 1.020 0.165 4.2 0.944 1.081 0.140 3.6 0.920 1.088 0.118 3.2 0.877 1.107 0.097 2.8 0.851 1.138 0.095 2.4 0.826 1.203 0.090 2.1 0.809 1.302 0.085 1.8 0.767 1.386 0.075 1.6 0.720 1.508 0.086 1.4 0.690 1.687 0.065 1.2 0.619 1.729 0.085 1.0 0.567 1.767 0.101 0.91 0.510 1.757 0.078 0.79 0.432 1.659 0.078 0.69 0.391 1.699 0.074 0.60 0.328 1.651 0.077 0.52 0.270 1.604 0.082 0.46 0.235 1.685 0.099 0.10 0.009 1.622 0.054 A-7 T bl A2 b2 M d' AF d . f M d I 2 P til 1 f 2 PGA I a e -elan san sigmas or o e I ro Ie I or eves M2P1K1 PGA=O.194 Freq Soil SA Median (Hz) AF 100.0 0.163 0.838 87.1 0.163 0.820 75.9 0.164 0.789 66.1 0.166 0.730 57.5 0.168 0.635 50.1 0.174 0.545 43.7 0.182 0.483 38.0 0.193 0.465 33.1 0.207 0.471 28.8 0.223 0.507 25.1 0.245 0.552 21.9 0.265 0.628 19.1 0.287 0.689 16.6 0.307 0.765 14.5 0.324 0.845 12.6 0.338 0.907 11.0 0.353 0.969 9.5 0.359 1.032 8.3 0.360 1.122 7.2 0.355 1.180 6.3 0.352 1.247 5.5 0.349 1.291 4.8 0.342 1.294 4.2 0.334 1.303 3.6 0.316 1.268 3.2 0.302 1.283 2.8 0.290 1.300 2.4 0.273 1.328 2.1 0.255 1.359 1.8 0.236 1.410 1.6 0.218 1.501 1.4 0.206 1.646 1.2 0.181 1.646 1.0 0.169 1.701 0.91 0.152 1.679 0.79 0.130 1.592 0.69 0.120 1.645 0.60 0.102 1.603 0.52 0.085 1.566 0.46 0.075 1.654 0.10 0.003 1.617 Lime ri ck Ge n era tin g Stat io n Report Numbe r: EXLNLlM065

-PR-001 , R evi s i on 0 Corre s pondence N o.: RS-14-069 Sigma In(AF) 0.051 0.051 0.051 0.051 0.051 0.052 0.054 0.057 0.064 0.075 0.095 0.106 0.112 0.116 0.116 0.115 0.111 0.100 0.087 0.108 0.110 0.113 0.097 0.087 0.095 0.086 0.057 0.061 0.074 0.100 0.097 0.074 0.088 0.111 0.095 0.087 0.076 0.081 0.083 0.098 0.049 M2P1K1 PGA=O.741 Freq Soil SA Median Sigma (Hz) AF In(AF) 100.0 0.571 0.772 0.054 87.1 0.574 0.751 0.054 75.9 0.578 0.714 0.054 66.1 0.585 0.647 0.054 57.5 0.597 0.549 0.054 50.1 0.621 0.468 0.055 43.7 0.657 0.418 0.058 38.0 0.704 0.413 0.064 33.1 0.762 0.430 0.072 28.8 0.827 0.474 0.084 25.1 0.911 0.525 0.103 21.9 0.986 0.607 0.114 19.1 1.063 0.673 0.119 16.6 1.126 0.752 0.121 14.5 1.180 0.835 0.119 12.6 1.222 0.899 0.118 11.0 1.263 0.962 0.112 9.5 1.274 1.025 0.102 8.3 1.268 1.116 0.088 7.2 1.240 1.175 0.108 6.3 1.222 1.242 0.111 5.5 1.200 1.287 0.113 4.8 1.170 1.290 0.097 4.2 1.135 1.299 0.087 3.6 1.069 1.264 0.095 3.2 1.014 1.280 0.086 2.8 0.970 1.297 0.057 2.4 0.910 1.325 0.061 2.1 0.843 1.356 0.074 1.8 0.778 1.406 0.099 1.6 0.714 1.496 0.096 1.4 0.670 1.640 0.073 1.2 0.587 1.640 0.087 1.0 0.544 1.694 0.109 0.91 0.485 1.672 0.094 0.79 0.413 1.587 0.085 0.69 0.377 1.639 0.075 0.60 0.318 1.598 0.079 0.52 0.263 1.562 0.081 0.46 0.230 1.650 0.097 0.10 0.009 1.614 0.054 A-8 Enclosure 2

SUMMARY

OF REGULATORY COMMITMENTS The following table identifies commitments made in this document. (Any other actions discussed in the submittal represent intended or planned actions. They are described to the NRC for the NRC's information and are not regulatory commitments.)

COMMITMENT TYPE COMMITTED COMMITMENT DATE OR ONE-TIME ACTION PROGRAMMATIC "OUTAGE" (Yes/No) (Yes/No) Limerick Generating Station, Units 1 and 2, will As determined by Yes No perform a High Frequency Confirmation NRC prioritization evaluation in accordance with EPRI Report following submittal 1025287, Section 3.4. of all nuclear power plant Seismic Hazard Re-evaluations, but no later than December 31, 2019.