Text

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) Re Recommendation 2.1 of The..
	ML14091A012
Person / Time
Site:	Dresden
Issue date:	03/31/2014
From:	Kaegi G; Exelon Generation Co
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	RS-14-067
	Download: ML14091A012 (62)
	v • d • e

tio RS-14-067 10 CFR 50.54(f)

March 31, 2014 U.S. Nuclear Regulatory Commission Attn: Document Control Desk 11555 Rockville Pike, Rockville, MD 20852 Dresden Nuclear Power Station, Units 2 and 3 Renewed Facility Operating License Nos. DPR-19 and DPR-25 NRC Docket Nos. 50-237 and 50-249

Subject:

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

References:

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

2. NEI Letter, Proposed Path Forward for NTTF Recommendation 2.1: Seismic Reevaluations, dated April9, 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 Page2 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 (EGG) provided the description of subsurface materials and properties and base case velocity profiles for Dresden Nuclear Power Station, Units 2 and 3.

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 Dresden Nuclear Power Station, Units 2 and 3, provides the information described in Section 4 of Reference 5 in accordance with the schedule identified in Reference 2. As described in Enclosure 1, Dresden Nuclear Power Station, Units 2 and 3, do not meet the requirements of SPID Sections 3.2 and 7 (Reference 5) and therefore screen in and a Risk Evaluation and Spent Fuel Pool evaluation will be performed as determined by NRC prioritization following submittal of all nuclear power plant Seismic Hazard Re-evaluations per Reference 1. Additionally, Dresden Nuclear Power Station, Units 2 and 3, will prepare an Expedited Seismic Evaluation Process (ESEP) Report in accordance with Reference 7, by December 31, 2014.

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 31st day of March 2014.

Respectfully submitted,

~r¥ Glen T. Kaegi 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. Dresden Nuclear Power Station, Units 2 and 3, Seismic Hazard and Screening Report

2. Summary of Regulatory Commitments cc: Director, Office of Nuclear Reactor Regulation Regional Administrator- NRC Region Ill NRC Senior Resident Inspector- Dresden Nuclear Power Station NRC Project Manager, NRR - Dresden Nuclear Power Station Ms. Jessica A. Kratchman, NRR/JLD/PMB, NRC Mr. Eric E. Bowman, NRRIDPRIPGCB, NRC or Ms. Eileen M. McKenna, NRO/DSRA/BPTS, NRC Illinois Emergency Management Agency- Division of Nuclear Safety

Enclosure 1 Dresden Nuclear Power Station, Units 2 and 3 Seismic Hazard and Screening Report (57 pages)

SEISMIC HAZARD AND SCREENING REPORT IN RESPONSE TO THE 10.14(f) INFORMATION REQUEST REGARDING FUKUSHIMA IEAR*TBRM TASK FORCI! RI!C,.,..,ATION 2.1: IEII.C for the Dresd* Genenltlllfl Station, Units 2 and 3 6100 Norlll Dresden Road lloll'ls, Illinois IIIUIIJ.97BS Facility Operating Ucenae Nos. DPR*18 and DPR*21 NRC Docket Nos. ITN 10.237 and ITN 50-248 Correspondence No.: RS-14-087 Exltan GenniiDn Qxqllny, LLO (l!lelaD)

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Exelon Seismic Hazard and Screening Report- Dresden Units 2 and 3 Report No.: SL-012190 Revision o- Initial Issue S&L Project No.: 11332-184 Nuclear Non-Safety Related Sections: Cover page, Executive Summary, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, and Appendix A

~-17-ZoJ Date Section: 4.2 All Sections

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Seismic Hazard and Screening Report- Dresden Units 2 and 3 Report No.: SL-012190 Revision 1 - Revised Pages (see below)

S&L Project No.: 11332-184 Nuclear Non-Safety Related Pages: vi, 4-1, 5-1, 6-1 Section: 4.2 Reviewed by: t3. ~S<:::{;::2r Brent Starks All Revisions

RECORD OF REVISIONS Revision Affected Pages Description 0 All Initial Issue 1 vi, 4-11 5-11 6-1 Replace pages vi, 4-1, 5-1, and 6-1. All other pages have been revised to reflect Revision 1 as the current revision.

I I

Dresden Generating Station Report No.: SL-012190. Revision 1 Correspondence No.: RS-14-067

Contents Contents ....................................................................................................................................... i Tables .. ,... ,,; ..... ,............................................................................................................................. iii Figures ........................................................................................................................................ iv Executive Summary .................................................................................................................... v 1 lntroduction ..................................................................................................................... 1-1 2 Seismic Hazard Reevaluation ........................................................................................ 2-1 2.1 Regional and Local Geology ................................................................................... 2-1 2.2 Probabilistic Seismic Hazard Analysis .................................................................... 2-2 2.2.1 Probabilistic Seismic Hazard Analysis Results .............................................. 2-2 2.2.2 Base Rock Seismic Hazard Curves ............................................................... 2-3 2.3 Site Response Evaluation ....................................................................................... 2-3 2.3.1 Description of Subsurface Material... ............................................................. 2-3 2.3.2 Development of Base Case Profiles and Nonlinear Material Properties ....... 2-6 2.3.3 Randomization of Base Case Profiles ......................................................... 2-14 2.3.4 Input Spectra ............................................................................................... 2-14 2.3.5 Methodology ................................................................................................ 2-14 2.3.6 Amplification Functions ................................................................................ 2-15 2.3.7 Control Point Seismic Hazard Curves ......................................................... 2-20 2.4 Control Point Response Spectra ........................................................................... 2-21 3 Plant Design Basis Ground Motion .............................................................................. 3-1 3.1 SSE Description of Spectral Shape ........................................................................ 3-1 3.2 Control Point Elevation ............................................................................................ 3-3 Dresden Generating Station Report No.: SL-012190, Revision 1 Correspondence No.. RS-14-067

Contents (cont'd.)

4 Screening Evaluation ..................................................................................................... 4-1 4.1 Risk Evaluation Screening (1 to 10Hz) .................................................................. 4-1 4.2 High Frequency Screening(> 10 Hz) ..................................................................... A-1 4.3 Spent Fuel Pool Evaluation Screening (1 to 10 Hz) ............................................... .4-2 5 Interim Actions ............................................................................................................... 5-1 5.1 Expedited Seismic Evaluation Process ................................................................... 5-1 5.2 Interim Evaluation of Seismic Hazard ..................................................................... 5-1 5.3 Seismic Walkdown Insights ..................................................................................... 5-2 5.4 Beyond-Design-Basis Seismic Insights ................................................................... 5-2 6 Conclusions ....................................................................................................................6-1 7 References ...................................................................................................................... 7-1 A Additional Tables ........................................................................................................... A-1 Dresden Generating Station Report No.: SL-012190, Revision 1 ii Correspondence No.: RS-14-067

Tables Table 2.3.1-1: Summary of geotechnical profile data for Dresden station ........................... 2-5 Table 2.3.2-1: Layer thicknesses, depths, and shear wave velocity (Vs) for Profiles 1, 2, and 3 for Dresden site .................................................................................. 2-7 Table 2.3.2-2: Layer thicknesses, depths, and shear wave velocity (Vs) for Profiles 4, 5, and 6 for Dresden site ................................................................................... 2-9 Table 2.3.2-3: Kappa values and weights used for site response analyses ....................... 2-13 Table 2.4-1: UHRS and GMRS for Dresden, 5% of critical damping .............................. 2-21 Table 3.1-1: Dresden Safe Shutdown Earthquake ground response spectrum, 5% critical damping ....................................................................................................... 3-1 Table A-1a: Mean and fractile seismic hazard curves for 100Hz (PGA) at Dresden, 5% of critical damping ........................................................................................... A-1 Table A-1 b: Mean and fractile seismic hazard curves for 25 Hz at Dresden, 5% of critical damping ....................................................................................................... A-2 Table A-1c: Mean and fractile seismic hazard curves for 10Hz at Dresden, 5% of critical damping ....................................................................................................... A-3 Table A-1d: Mean and fractile seismic hazard curves for 5Hz at Dresden, 5% of critical damping ....................................................................................................... A-4 Table A-1e: Mean and fractile seismic hazard curves for 2.5 Hz at Dresden, 5% of critical damping ....................................................................................................... A-5 Table A-1f: Mean and fractile seismic hazard curves for 1 Hz at Dresden, 5% of critical damping ....................................................................................................... A-6 Table A-1 g: Mean and fractile seismic hazard curves for 0.5 Hz at Dresden, 5% of critical damping ....................................................................................................... A-7 Table A-2a: Amplification functions for Dresden, 5% of critical damping ......................... A-8 Table A-2b1: Median AFs and sigmas for Model 1, Profile 1, for 2 PGA levels................. A-9 Table A-2b2: Median AFs and sigmas for Model2, Profile 1, for 2 PGA levels ............... A-10 Dresden Generating Station Report No.: SL-012190, Revision 1 iii Correspondence No.: RS-14-067

Figures Figure 2.3.2-1: Shear wave velocity (Vs} for Profiles 1, 2, and 3 for Dresden site ................ 2-7 Figure 2.3.2-2: Shear wave velocity (Vs} for Profiles 4, 5, and 6 for Dresden site ................ 2-9 Figure 2.3.6-1: Example suite of amplification factors (5% 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 (K1} 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 .......................................................................................................... 2-16 Figure 2.3.6-2: Example suite of amplification factors (5% critical damping pseudo absolute acceleration spectra) developed for the mean base-case profile (P1}, linear site response (model M2), and base-case kappa (K1} 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 ......................................................................... 2-18 Figure 2.3.7-1: Control point mean hazard curves for spectral frequencies of 0.5, 1, 2.5, 5, 10, 25 and 100Hz (PGA) at Dresden station (5% of critical damping) ....... 2-20 Figure 2.4-1: Plots of 1E-4 and 1E-5 UHRS and GMRS at control point for Dresden, 5%

critical damping ........................................................................................... 2-22 Figure 3.1-1: Dresden SSE horizontal ground response spectrum, 5% critical damping ... 3-2 Dresden Generating Station Report No.: Sl-012190, Revision 1 iv Correspondence No.: RS-14-067

Executive Summary PURPOSE Following the accident at the Fukushima Daiichi 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 in 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 against present-day NRC requirements.

This report provides the information requested in items (1) through (7) of the "Requested Information" section and Attachment 1 of the 50.54(f) letter (Reference 1) pertaining to NTTF Recommendation 2.1 for Dresden Generating Station, Units 2 and 3, in accordance with the documented intention of Exelon Generating Company transmitted to the NRC via letter dated April 29, 2013 (Reference 23).

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 Dresden station was performed to develop a Ground Motion Response Spectrum (GMRS) for comparison with the Safe Shutdown Earthquake (SSE). The new GMRS represents a beyond-design-basis seismic demand developed by more modern techniques than were used for plant licensing. Consistent with NRC letter dated February 20, 2014, (Reference 32) the seismic hazard reevaluations performed in response to the 50.54(f) letter (Reference 1) are distinct from the current design or licensing bases of operating plants. Therefore, the results generally do not call into question the operability or functionality of SSCs and are not expected to be reportable pursuant to 10 CFR 50.72, "Immediate notification requirements for operating nuclear power reactors," and 10 CFR 50.73, "Licensee event report system."

Section 2 provides a summary of the regional and local geology, seismicity, other major inputs to the seismic hazard reevaluation, and detailed seismic hazard results including definition of the GMRS. Seismic hazard analysis for Dresden station, including the 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 (EPRI) (Reference 15). A more in-depth discussion of the calculation methods used in the seismic hazard reevaluation can be found in References 3, 7, 8, 17, and 18. Section 3 describes the characteristics of the appropriate plant-level SSE. Section 4 provides a comparison of the GMRS to the SSE. Sections 5 and 6 discuss interim actions and conclusions, respectively.

Dresden Generating Station Report No.: SL-012190, Revision 1 v

Correspondence No.: RS-14-067

CONCLUSIONS The GMRS exceeds the SSE for a portion of the frequency range from 1 Hz to 10 Hz.

Therefore, Dresden station screens in for a risk evaluation and a spent fuel pool integrity evaluation in response to NTTF 2. 1: Seismic. Due to the GMRS exceeding the SSE in the frequency range above 10 Hz, high frequency exceedances can be addressed for Dresden station in the risk evaluation process. Dresden station will perform the Expedited Seismic Evaluation Process (ESEP) as an interim action prior to completion of the risk evaluation per the ESEP guidance (Reference 4). These actions will be performed in accordance with the schedule for central and eastern United States (CEUS) nuclear plants provided via letter from the industry to the NRC dated April 9, 2013 (Reference 6), as agreed to by the NRC in the May 7, 2013 letter to the industry (Reference 29).

Dresden Generating Station Report No.: SL-012190, Revision 1 vi Correspondence No.: RS-14-067

1 Introduction Following the accident at the Fukushima Daiichi nuclear power plant resulting from the March 11, 2011, Great Tohoku Earthquake and subsequent tsunami, the NRC Commission established a Near Term Task Force (NTTF) to conduct a systematic review of NRC processes and regulations and to determine if the agency should make additional improvements to its regulatory system. The NTIF 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 that requests information to assure that these recommendations are addressed by all U.S. nuclear power plants (Reference 1). The 50.54(f) letter requests that licensees and holders of construction permits under 10 CFR Part 50 (Reference 2) reevaluate the seismic hazards at their sites against present-day NRC requirements. Depending on the comparison between the reevaluated seismic hazard and the current design basis, the result is either no further risk evaluation or the performance of a seismic risk assessment. Risk assessment approaches acceptable to the staff include a seismic probabilistic risk assessment (SPRA), or a seismic margin assessment (SMA). Based upon the risk assessment results, the NRC staff will determine whether additional regulatory actions are necessary.

This report provides the information requested in items (1) through (7) of the "Requested Information" section and Attachment 1 of the 50.54(f) letter (Reference 1) pertaining to NTTF Recommendation 2.1 for the Dresden Generating Station, Units 2 and 3, (Dresden station), located in Grundy County, Illinois. In providing this information, Exelon followed the guidance provided in the Seismic Evaluation Guidance: Screening, Prioritization, and Implementation Details (SPID) for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1: Seismic (Reference 3). The Augmented Approach, Seismic Evaluation Guidance: Augmented Approach for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1: Seismic (Reference 4), has been developed as the process for evaluating critical plant equipment as an interim action to demonstrate additional plant safety margin, prior to performing the complete plant seismic risk evaluations. The SPID (Reference 3) and Augmented Approach (Reference 4) have been endorsed by the NRC in letters to NEI per Reference 30 and Reference 29 respectively.

Dresden Generating Station Report No.: SL-012190, Revision 1 1-1 Correspondence No.: RS-14-067

The original geology and seismology investigations for Dresden station are documented in Volume Ill, Section 4 of the Dresden Unit 2 Plant Design and Analysis Report (PDAR)

(Reference 19). The Safe Shutdown Earthquake (SSE) ground motion was developed based on the seismology, geology, and other pertinent data of the site and is used for the design of seismic Category I systems, structures and components. (Reference 10)

In response to the 50.54(f) letter (Reference 1) and following the SPID guidance (Reference 3), a seismic hazard reevaluation for Dresden station was performed. For screening purposes, a Ground Motion Response Spectrum (GMRS) was developed.

Dresden Generating Station Report No.: SL-012190, Revision 1 1-2 Correspondence No.: RS-14-067

2 Seismic Hazard Reevaluation The Dresden station site is located 15 miles southwest of Joliet, Illinois, in the northeast quarter of the Morris 15-minute quadrangle, Goose Lake Township, Grundy County, adjacent to where the Des Plaines and Kankakee Rivers converge to form the Illinois River. The site is within the Central Stable Region of the North American Continent.

The Dresden site has a thin (less than 10 feet) layer of soil, mostly glacial drift, and overlaying bedrock. (Reference 10)

The Dresden site area is placed in Zone 1 (zone of minor damage) on the seismic probability map of the 1958 Uniform Building Code. The August 1958 Seismic Regionalization map by Richter gives general predictions of probable maximum earthquake intensity and, recognizing that lines between the areas of differing intensity are approximations only, shows the Dresden region as Modified Mercalli Intensity (MMI)

VII to VIII. (Reference 10)

At the time of licensing, only a few earthquakes of significant intensity in Northern Illinois had been reported since 1800, and none had been accompanied by clear-cut surface faulting. A seismological study of the region was performed and reported that historically there may have been a maximum MMI VII earthquake reported in the Dresden area.

The recommended design earthquake for safe shutdown was a strong motion earthquake having a 0.2g ground acceleration. (Reference 10) 2.1 REGIONAL AND LOCAL GEOLOGY The site is located just west of the area where the Des Plaines and Kankakee Rivers flow together to form the Illinois River. The terrain is slightly hilly with a maximum relief at the site of about 25 feet. Regional relief is on the order of 200 feet. The site area is within the Central Lowland Physiographic Provence. (Reference 10)

A thin (less than 10-foot) mantle of soil, mostly glacial drift, overlies bedrock at the site.

The upper unit of bedrock is the Spoon formation of the Pennsylvanian age (300 million years before present [MYBP]). The Spoon is sandstone that varies in thickness beneath the site from 0 to 45 feet. A thin soil horizon is present below the Spoon overlying rocks of the Upper Ordovician (450 to 430 MYBP) Marquoketa formation. The Marquoketa consists of a 20- to 45-foot thick upper limestone member, the Fort Atkinson limestone, and a 70-foot thick lower shale member, the Scales shale. Below the Marquoketa formation are approximately 1000 feet of limestone, dolomites, and sandstones ranging in age from Middle Ordovician (450 MYBP) to Cambrian (570 MYBP). These rocks lie on the Precambrian crystalline basement. (Reference 10)

Dresden Generating Station Report No.: SL-012190, Revision 1 2-1 Correspondence No.: RS-14-067

The Dresden site lies within the Central Stable Region of the North American Continent.

This region extends from the Rocky Mountains to the Appalachian Plateaus and is relatively undeformed tectonically. It is characterized by a pattern of large basins, domes, and arches which formed throughout the Paleozoic Era (570 to 225 MYBP). The site is located on the northeast flank of one of these structures, the Illinois Basin. The north-northwest striking LaSalle anticlinal belt, a major structural element within the Illinois Basin, lies a few miles west of the site. The LaSalle anticline is a band of en echelon folds which formed during the Mississippian and Pennsylvanian periods (345 to 280 MYBP). (Reference 10)

The northwest trending Kankakee Arch forms the northeastern boundary of the Illinois Basin and intersects the Wisconsin Arch to the North. (Reference 10) 2.2 PROBABILISTIC SEISMIC HAZARD ANALYSIS 2.2.1 Probabilistic Seismic Hazard Analysis Results In accordance with the 50.54(f) letter (Reference 1) and following the SPID guidance (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 7) together with the updated EPRI Ground-Motion Model for CEUS (Reference 8). For the PSHA, a lower bound moment magnitude cutoff of 5.0 was used, as specified in the 50.54(f) letter.

For the PSHA, the CEUS-SSC (Reference 7) background seismic sources out to a distance of 400 miles around Dresden were included. This distance exceeds the 200 mile recommendation contained in NRC Regulatory Guide 1.208 (Reference 18) and was chosen for completeness. Background sources included in this site analysis are the following:

1. Illinois Basin Extended Basement (IBEB)

2. Mesozoic and younger extended prior- narrow (MESE-N)

3. Mesozoic and younger extended prior- wide (MESE-W)

4. Midcontinent-Craton alternative A (MIDC_A)

5. Midcontinent-Craton alternative B (MIDC_B)

6. Midcontinent-Craton alternative C (MIDC_C)

7. Midcontinent-Craton alternative D (MIDC_D)

8. Non-Mesozoic and younger extended prior- narrow (NMESE-N)

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

10. Paleozoic Extended Crust narrow (PEZ_N)

11. Paleozoic Extended Crust wide (PEZ_W)

12. Reelfoot Rift (RR)

13. Reelfoot Rift including the Rough Creek Graben (RR-RCG)

14. Study region (STUDY_R)

Dresden Generating Station Report No .. SL-012190, Revision 1 2-2 Correspondence No.: RS-14-067

For sources of large magnitude earthquakes, designated Repeated Large Magnitude Earthquake (RLME) sources in CEUS-SSC (Reference 7), the following sources lie within 621 miles (1000 km) of the site and were included in the analysis:

1. Commerce

2. Eastern Rift Margin Fault northern segment (ERM-N)

3. Eastern Rift Margin Fault southern segment (ERM-S)

4. Marianna

5. New Madrid Fault System (NMFS)

6. Wabash Valley For each of the above background and RLME sources, the mid-continent version of the updated CEUS EPRI GMM (Reference 8) was used.

2.2.2 Base Rock Seismic Hazard Curves Consistent with the SPID (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 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) Request for Information (Reference 1) and in the SPID (Reference 3), for nuclear power plant sites that are not founded on hard rock (hard rock is defined as having a shear wave velocity of at least 9285 ft/sec), a site response analysis was performed for Dresden station.

2.3.1 Description of Subsurface Material The Dresden station is located near Joliet, Illinois. The site consists of a few feet of glacial drift soils overlying at least 1, 000 feet of sedimentary rock below which lies Precambrian Basement. Table 2.3.1-1 shows the stratigraphic column and unit elevations with the SSE defined at elevation 515 feet, at the top of the Pottsville Formation. Depth to Precambrian basement is unspecified (Reference 14) and, based on unit elevations listed on Table 2.3.1-1, assumed 1 to exceed a depth of 1,000 feet.

A thin (less than 10 feet) mantle of soil, mostly glacial drift, overlies the bedrock at this site. In the vicinity of the power black the soil depth is approximately 3 to 4 feet thick.

The upper bedrock is the Spoon Formation of the Pennsylvanian age, or Pennsylvanian Pottsville sandstone, which varies in thickness up to 50 feet (Reference 10 and Reference 19). The Pottsville sandstone is composed predominantly of cemented sub-angular fine to medium grains of quartz containing varying amounts of mica (Reference 19). The ISFSI geotechnical investigation report indicates the Spoon Formation is composed of two layers: Layer 1 is light gray slightly weathered sandstone to 11 feet depth; Layer 2 is light gray sandstone to 42 feet depth (Reference 16).

1 Assumptions discussed in Section 2 are provided by EPRI engineers (Reference 15) in accordance with implementation of the SPID (Reference 3) methodology.

Dresden Generating Station Report No.: SL-012190, Revision 1 2-3 Correspondence No.: RS-14-067

The Pottsville sandstone, where present, is immediately underlain by the Divine limestone member of the Ordovician Maquoketa formation, featuring a 20 to 45 feet thick upper limestone member, the Fort Atkinson limestone, composed of light brown to light gray fine to coarse-grained crystalline rock containing occasional stylolites, solution channels, joints, cavities, and thin layers of clay (Reference 10 and Reference 19). In areas where the Pottsville sandstone is not present, the Divine limestone is the uppermost rock (Reference 19). The ISFSI geotechnical investigation found that the surface of the limestone ranges to a depth of 42 feet (Reference 16).

The Maquoketa shale underlying the Divine limestone consists of dark gray dolomitic shale with layers of shale and argillaceous dolomite, ranging in thickness from approximately 65 to 70 feet. There is considerable variation in the dolomite content of the Maquoketa shale, resulting in a variation of the type and character of the rock.

Where the dolomite content is high, the rock consists of argillaceous dolomite and is very sound. Where the dolomite content is low, the rock consists of fissile shale, which readily breaks and rapidly deteriorates in water (Reference 19).

Below the Maquoketa formation is approximately 1000 feet of limestone, dolomites, and sandstones ranging in age from Middle Ordovician to Cambrian. These rocks lie on Precambrian crystalline basement (Reference 10). Detailed information on the Cambrian and Precambrian rocks beneath the Dresden site is not available (Reference 14).

Dresden Generating Station Report No.: SL-012190, Revision 1 2-4 Correspondence No.: RS-14-067

Table 2.3.1-1: Summary of geotechnical profile data for Dresden station (Reference 28)

Elevations of Layer Range in I Compresslo~al 1 Poisson's Boundaries At Reactor Thickness Density Shear Wave Soli/Rock Description and Age Wave Veloc1ty Rati 0 Buildings Across (pcf) Velocity (fps)

(fps)

(ft, MSL) Site (ft) 517"1o 515 0-40 Glacial drift and topsoil NIA NIA NIA N/A Pennsylvanian Pottsville Formation, 515b to 475 0-50 130-138 2600 2700-5000 0.20-0.25 sandstone Ordovician Divine limestone member, 475 to 455° 5-70 limestone 155-173 8600 6600-15300 0.20 Ordovician Maquoketa shale member, 455 to 385 65-70 dolomitic shale with layers of shale and 134-171 3900-4700 3800-9800 0.22-0.28 argillaceous dolomite 385 to 155 230 Ordovician Galena Formation, dolomite 167 4700 8500 0.28 Ordovician Platteville Formation, 155 to 40 115 NIA N/A N/A N/A dolomite and limestone Ordovician Glenwood Formation, 40to 25 5-30 NIA NIA NIA NIA sandstone Ordovician St Peter Formation, 25 to -140 165 sandstone N/A N/A N/A N/A Ordovician Shakopee Formation,

-140 to -220 70-90 NIA N/A N/A N/A dolomite Ordovician New Richmond Formation,

-220 to -270 45-55 NIA NIA NIA N/A sandstone and dolomite

-270 to -480 210 Ordovician Oneota Formation, dolomite N/A N/A NIA N/A

-480 toN/A NIA Cambrian dolomite and sandstone NIA N/A NIA NIA Precambrian granite, quartz monzonite, N/A N/A N/A N/A N/A N/A rhvolite POfPhvrv, felsite

Surface of finish grade is nominally at El. 517 ft MSL in the vicinity of the main power bloclc 0

The control point elevation for the SSE and tPEEE HCLPF is at the top of the bedrock, which is at El. 515ft MSL.

Bottom of the deepest foundation is at El. 473ft MSL, at the surface of the Ordovician limestone.

Dresden Generating Station 2-5 Report No.: SL.(J12190, Revision 1 Correspondence No.. RS-14-067

2.3.2 Development of Base Case Profiles and Nonlinear Material Properties Table 2.3.1-1 shows the recommended shear-wave velocities (Vs) and unit weights along with elevations and corresponding stratigraphy. From Table 2.3.1-1 the SSE control point is at elevation 515 feet at the top of the Pottsville Formation.

Shear-wave velocities listed on Table 2.3.1-1 were based on compressional-wave velocity measurements and assumed 1 Poisson ratios and extend into the Galena Formation dolomites, the deepest velocities specified. To develop the mean base-case profile, the listed shear-wave velocities and unit weights were used, which extended to a depth below the SSE of 360 feet. Below this elevation, in general, a gradient of 0.5 ft/s!ft (Reference 3) was used to extend the profile. To accommodate uncertainty in depth to hard rock (Precambrian basement) two depths were considered: 1,000 feet randomized

+/- 300 feet (Profile 1) and 5,000 feet randomized +/- 1,500 feet (Profile 4). The depth randomization reflects +/- 30% of the depth and was included to provide a realistic broadening of the fundamental resonance at deep sites rather than reflect actual random variations to basement shear-wave velocities across a footprint. Lower- and upper-range profiles, Profile 2 and Profile 3 respectively for shallow depths to Precambrian basement, and Profile 5 and Profile 6 respectively for deep depths to Precambrian basement were developed using two scale factors: 1.25 reflecting shear-wave velocity estimates over the top 360 feet and 1.57 below. The scale factors of 1.25 and 1.57 reflect o1-11n of about 0.2 and about 0.35 based on the SPID (Reference 3) 101h and 901h fractiles which implies a 1.28 scale factor on oil. The upper-range deep profile P6 encountered hard rock shear-wave velocities (9,285 ft/s) at a depth below the SSE control point of about 2,200 feet.

The six base-case profiles are shown in Figure 2.3.2-1 and Figure 2.3.2-2 and listed in Table 2.3.2-1 and Table 2.3.2-2.

1 Assumptions discussed in Section 2 are provided by EPRI engineers (Reference 15) in accordance with implementation of the SPID (Reference 3) methodology.

Dresden Generating Station Report No.: SL-012190. Revision 1 Correspondence No.: RS-14-067

Vs Profiles 1, 2, and 3 for Dresden site Vs (ft/sec) 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 0

100 200 300 400

-Profilel g 500

..c

c. 600 Q

Ill -Profile2 700 800 -Profile3 900 1000 1100 Figure 2.3.2-1: Shear wave velocity (Vs) for Profiles 1, 2, and 3 for Dresden site (Reference 28)

Table 2.3.2-1: Layer thicknesses, depths, and shear wave velocity (Vs} for Profiles 1, 2, and 3 for Dresden site (Reference 28}

Profile 1 (P1) Profile 2 (P2) Profile 3 (P3)

Thickness Thickness Thickness Depth (ft) Vs(ft/s) Depth (ft) Vs(ft/s) Depth (ft) Vs(ft/s)

(ft} (ft) (ft) 0 2600 0 2080 0 3250 5.0 5.0 2600 5.0 5.0 2080 5.0 5.0 3250 5.0 10.0 2600 5.0 10.0 2080 5.0 10.0 3250 5.0 15.0 2600 5.0 15.0 2080 5.0 15.0 3250 5.0 20.0 2600 5.0 20.0 2080 5.0 20.0 3250 5.0 25.0 2600 5.0 25.0 2080 5.0 25.0 3250 5.0 30.0 2600 5.0 30.0 2080 5.0 30.0 3250 5.0 35.0 2600 5.0 35.0 2080 5.0 35.0 3250 5.0 40.0 2600 5.0 40.0 2080 5.0 40.0 3250 10.0 50.0 8600 10.0 50.0 6880 10.0 50.0 10749 10.0 60.0 8600 10.0 60.0 6880 10.0 60.0 10749 10.0 70.0 4300 10.0 70.0 3440 10.0 70.0 5375 10.0 80.0 4300 10.0 80.0 3440 10.0 80.0 5375 10.0 90.0 4300 10.0 90.0 3440 10.0 90.0 5375 10.0 100.0 4300 10.0 100.0 3440 10.0 100.0 5375 10.0 110.0 4300 10.0 110.0 3440 10.0 110.0 5375 10.0 120.0 4300 10.0 120.0 3440 10.0 120.0 5375 10.0 130.0 4300 10.0 130.0 3440 10.0 130.0 5375 10.0 140.0 4700 10.0 140.0 3760 10.0 140.0 5875 Dresden Generating Station Report No.: SL-012190, Revision 1 Correspondence No.: RS-14-067

Table 2.3.2~1: (Continued)

Profile 1 (P1) Profile 2 (P2} Profile 3 (P3)

Thickness Thickness Vs(ft/s) Thickness Vs(ft/s)

Depth (It} Vs(ft/s) Depth (It} Depth (It}

(It) (It) (It) 10.0 150.0 4700 10.0 150.0 3760 10.0 150.0 5875 10.0 160.0 4700 10.0 160.0 3760 10.0 160.0 5875 10.0 170.0 4700 10.0 170.0 3760 10.0 170.0 58H 10.0 180.0 4700 10.0 180.0 3760 10.0 180.0 587 10.0 190.0 4700 10.0 190.0 3760 10.0 190.0 5875 10.0 200.0 4700 10.0 200.0 3760 10.0 200.0 5875 10.0 210.0 4700 10.0 210.0 3760 10.0 210.0 5875 10.0 220.0 4700 10.0 220.0 3760 10.0 220.0 5875 10.0 230.0 4700 10.0 230.0 3760 10.0 230.0 5875 10.0 240.0 4700 10.0 240.0 3760 10.0 240.0 5875 10.0 250.0 4700 10.0 250.0 3760 10.0 250.0 5875 10.0 260.0 4700 10.0 260.0 3760 10.0 260.0 5875 10.0 270.0 4700 10.0 270.0 3760 10.0 270.0 5875 10.0 280.0 4700 10.0 280.0 3760 10.0 280.0 5875 10.0 290.0 4700 10.0 290.0 3760 10.0 290.0 5875 10.0 300.0 4700 10.0 300.0 3760 10.0 300.0 5875 10.0 310.0 4700 10.0 310.0 3760 10.0 310.0 5875 10.0 320.0 4700 10.0 320.0 3760 10.0 320.0 5875 10.0 330.0 4700 10.0 330.0 3760 10.0 330.0 5875 10.0 340.0 4700 10.0 340.0 3760 10.0 340.0 5875

-*H 10.0 350.0 4700 10.0 350.0 3760 5875 10.0 360.0 4700 1 1o.o 360.0 3760 360.0 5875 10.0 370.0 5002 10.0 370.0 3186 10.0 370.0 7854 10.0 380.0 5007 10.0 380.0 3190 10.0 380.0 7861 10.0 390.0 5012 10.0 390.0 3193 10.0 390.0 7869 10.0 400.0 5017 10.0 400.0 3196 10.0 400.0 7877 10.0 410.0 5022 10.0 410.0 3199 10.0 410.0 7885 10.0 420.0 5027 10.0 420.0 3202 10.0 420.0 7893 10.0 430.0 5032 10.0 430.0 3206 10.0 430.0 7901 10.0 440.0 5037 10.0 440.0 3209 10.0 440.0 7908 10.0 450.0 5042 10.0 450.0 3212 10.0 450.0 7916 10.0 460.0 5047 10.0 460.0 3215 10.0 460.0 7924 10.0 470.0 5052 10.0 470.0 218 10.0 470.0 7932 10.0 480.0 5057 10.0 480.0 21 10.0 480.0 7940 10.0 490.0 5062 10.0 490.0 3225 10.0 490.0 7948 10.0 500.0 5067 10.0 500.0 3228 10.0 500.0 7956 100.0 600.0 5092 100.0 600.0 3244 100.0 600.0 7995 100.0 700.0 5142 100.0 700.0 3276 100.0 700.0 8073 100.0 800.0 5192 100.0 800.0 3307 100.0 800.0 8152 100.0 900.0 5242 100.0 900.0 3339 100.0 900.0 8230 100.0 1000.0 5292 100.0 1000.0 3371 100.0 1000.0 8309 3280.8 4280.8 9285 3280.8 4280.8 9285 3280.8 4280.8 9285 Dresden Generating Station Report No.: SL-012190, Revision 1 2-8 Correspondence No.: RS-14-067

Vs Profiles 4, 5, and 6 for Dresden site Vs (ft/sec) 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 0

500 1000 1500 2000

-Profile4 g

.c 2500 c

i' 3000 -ProfileS 3500 4000 -Profile6 4500 5000 5500 Figure 2.3.2-2: Shear wave velocity (Vs) for Profiles 4, 5, and 6 for Dresden site (Reference 28)

Table 2.3.2-2: Layer thicknesses, depths, and shear wave velocity (Vs) for Profiles 4, 5, and 6 for Dresden site (Reference 28)

Profile 4 (P4) Profile 5 (P5) Profile 6 (P6)

Thickness Thickness Thickness (ft)

Depth (ft) Vs(ftls) (ft)

Depth (ft) Vs(ftls) 0 2600 0 2080 0 3250 5.0 5.0 2600 5.0 5.0 2080 5.0 5.0 3250 5.0 10.0 2600 5.0 10.0 2080 5.0 10.0 3250 5.0 15.0 2600 5.0 15.0 2080 5.0 15.0 3250 5.0 20.0 2600 5.0 20.0 2080 5.0 20.0 3250 5.0 25.0 2600 5.0 25.0 2080 5.0 25.0 3250 5.0 30.0 2600 5.0 30.0 2080 5.0 30.0 3250 5.0 35.0 2600 5.0 35.0 2080 5.0 35.0 3250 5.0 40.0 2600 5.0 40.0 2080 5.0 40.0 3250 10.0 50.0 8600 10.0 50.0 6880 10.0 50.0 10749 10.0 60.0 8600 10.0 60.0 6880 10.0 60.0 10749 10.0 70.0 4300 10.0 70.0 3440 10.0 70.0 5375 10.0 80.0 4300 10.0 80.0 3440 10.0 80.0 5375 10.0 90.0 4300 10.0 90.0 3440 10.0 90.0 5375 10.0 100.0 4300 10.0 100.0 3440 10.0 100.0 5375 10.0 110.0 4300 10.0 110.0 3440 10.0 110.0 5375 Dresden Generating Station Report No.: SL-012190, Revision 1 2-9 Correspondence No.: RS-14-067

Table 2.3.2-2: (Continued)

Profile 4 (P4) Profile 5 (P5) Profile 6 (P6)

Thickness Thickness Thickness Depth (ft) Vs(ft/s) Depth (ft) Vs(ftis) Depth (ft) Vs(ft/s)

(ft) (ft) (ft) 10.0 120.0 4300 10.0 120.0 3440 10.0 120.0 5375 10.0 130.0 4300 10.0 130.0 3440 10.0 130.0 5375 10.0 140.0 4700 10.0 140.0 3760 10.0 140.0 5875 10.0 150.0 4700 10.0 150.0 3760 10.0 150.0 5875 10.0 160.0 4700 10.0 160.0 3760 10.0 160.0 5875 10.0 170.0 4700 10.0 170.0 3760 10.0 170.0 5875 10.0 180.0 4700 10.0 180.0 3760 10.0 180.0 5875 10.0 190.0 4700 10.0 190.0 3760 10.0 190.0 5875 10.0 200.0 4700 10.0 200.0 3760 10.0 200.0 5875 10.0 210.0 4700 10.0 210.0 3760 10.0 210.0 5875 10.0 220.0 4700 10.0 220.0 3760 10.0 220.0 5875 10.0 230.0 4700 10.0 230.0 3760 10.0 230.0 5875 10.0 240.0 4700 10.0 240.0 3760 10.0 240.0 5875 10.0 250.0 4700 10.0 250.0 3760 10.0 250.0 5875 10.0 260.0 4700 10.0 260.0 3760 10.0 260.0 5875 10.0 270.0 4700 10.0 270.0 3760 10.0 270.0 5875 10.0 280.0 4700 10.0 280.0 3760 10.0 280.0 5875 10.0 290.0 4700 10.0 290.0 3760 10.0 290.0 5875 10.0 300.0 4700 10.0 300.0 3760 10.0 300.0 5875 10.0 310.0 4700 10.0 310.0 3760 10.0 310.0 5875 10.0 320.0 4700 10.0 320.0 3760 10.0 320.0 5875 10.0 330.0 4700 10.0 330.0 3760 10.0 330.0 5875 10.0 340.0 4700 10.0 340.0 3760 10.0 340.0 5875 10.0 350.0 4700 10.0 350.0 3760 10.0 350.0 5875 10.0 360.0 4700 10.0 360.0 3760 10.0 360.0 5875 10.0 370.0 5002 10.0 370.0 3186 10.0 370.0 7854 10.0 380.0 5007 10.0 380.0 3190 10.0 380.0 7861 10.0 390.0 5012 10.0 390.0 3193 10.0 390.0 7869 10.0 400.0 5017 10.0 400.0 3196 10.0 400.0 7877 10.0 410.0 5022 10.0 410.0 3199 10.0 410.0 7885 10.0 420.0 5027 10.0 420.0 3202 10.0 420.0 7893 10.0 430.0 5032 10.0 430.0 3206 10.0 430.0 7901 10.0 440.0 5037 10.0 440.0 3209 10.0 440.0 7908 10.0 450.0 5042 10.0 450.0 3212 10.0 450.0 7916 10.0 460.0 5047 10.0 460.0 3215 10.0 460.0 7924 10.0 470.0 5052 10.0 470.0 3218 10.0 470.0 7932 10.0 480.0 5057 10.0 480.0 3221 10.0 480.0 7940 10.0 490.0 5062 10.0 490.0 3225 10.0 490.0 7948 Dresden Generating Station Report No.: SL-012190, Revision 1 2-10 Correspondence No.: RS-14-067

Table 2.3.2~2: (Continued)

Profile 4 (P4) Profile 5 (P5) Profile 6 (P6)

Thickness Thickness Thickness Vs(fUs}

{ft}

Depth (ft) Vs(fUs) (ft}

Depth (ft} Vs(fUs) (ft)

Depth {ft) 10.0 500.0 5067 10.0 500.0 3228 10.0 500.0 7956 100.0 600.0 5092 100.0 600.0 3244 100.0 600.0 7995 100.0 700.0 5142 100.0 700.0 3276 100.0 700.0 8073 100.0 800.0 5192 100.0 800.0 3307 100.0 800.0 8152 100.0 900.0 5242 100.0 900.0 3339 100.0 900.0 8230 100.0 1000.0 5292 100.0 1000.0 3371 100.0 1000.0 8309 100.0 1100.0 5342 100.0 1100.0 3403 100.0 1100.0 8387 100.0 1200.0 5392 100.0 1200.0 3435 100.0 1200.0 8466 100.0 1300.0 5442 100.0 1300.0 3467 100.0 1300.0 8544 100.0 1400.0 5492 100.0 1400.0 3499 100.0 1400.0 8623 100.0 1499.9 5542 100.0 1499.9 3530 100.0 1499.9 8701 100.0 1599.9 5592 100.0 1599.9 3562 100.0 1599.9 8780 100.0 1699.9 5642 100.0 1699.9 3594 100.0 1699.9 8858 100.0 1799.9 5692 100.0 1799.9 3626 100.0 1799.9 8937 100.0 1899.9 5742 100.0 1899.9 3658 100.0 1899.9 9015 100.0 1999.9 5792 100.0 1999.9 3690 100.0 1999.9 9094 100.0 2099.9 5842 100.0 2099.9 3721 100.0 2099.9 9172 100.0 2199.9 5892 100.0 2199.9 3753 100.0 2199.9 9251 100.0 2299.9 5942 100.0 2299.9 3785 100.0 2299.9 9285 100.0 2399.9 5992 100.0 2399.9 3817 100.0 2399.9 9285 100.0 2499.9 6042 100.0 2499.9 3849 100.0 2499.9 9285 100.0 2599.9 6092 100.0 2599.9 3881 100.0 2599.9 9285 100.0 2699.9 6142 100.0 2699.9 3913 100.0 2699.9 9285 100.0 2799.9 6192 100.0 2799.9 3944 100.0 2799.9 9285 100.0 2899.9 6242 100.0 2899.9 3976 100.0 2899.9 9285 100.0 2999.9 6292 100.0 2999.9 4008 100.0 2999.9 9285 100.0 3099.9 6342 100.0 3099.9 4040 100.0 3099.9 9285 100.0 3199.9 6392 100.0 3199.9 4072 100.0 3199.9 9285 100.0 3299.9 6442 100.0 3299.9 4104 100.0 3299.9 9285 Dresden Generating Station Report No.: SL-012190, Revision 1 2-11 Correspondence No.: RS-14-067

Table 2.3.2-2: (Continued)

Profile 4 (P4) Profile 5 (P5) Profile 6 (P6)

Thickness Thickness Thickness

{ttl Depth (ft) Vs(ft/s) (ft)

Depth (ft) Vs(ftls) Depth (ft) Vs(ft/s) l!!L 100.0 3399.9 6492 100.0 3399.9 4136 100.0 3399.9 9285 100.0 3499.9 6542 100.0 3499.9 4167 100.0 3499.9 9285 100.0 3599.9 6592 100.0 3599.9 4199 100.0 3599.9 9285 100.0 3699.9 6642 100.0 3699.9 4231 100.0 3699.9 9285 100.0 3799.9 6692 100.0 3799.9 4263 100.0 3799.9 9285 100.0 3899.8 6742 100.0 3899.8 4295 100.0 3899.8 9285 100.0 3999.8 6792 100.0 3999.8 4327 100.0 3999.8 9285 100.0 4099.8 6842 100.0 4099.8 4358 100.0 4099.8 9285 100.0 4199.8 6892 100.0 4199.8 4390 100.0 4199.8 9285 100.0 4299.8 6942 100.0 4299.8 4422 100.0 4299.8 9285 100.0 4399.8 6992 100.0 4399.8 4454 100.0 4399.8 9285 100.0 4499.8 7042 100.0 4499.8 4486 100.0 4499.8 9285 100.0 4599.8 7092 100.0 4599.8 4518 100.0 4599.8 9285 100.0 4699.8 7142 100.0 4699.8 4550 100.0 4699.8 9285 100.0 4799.8 7192 100.0 4799.8 4581 100.0 4799.8 9285 100.0 4899.8 7242 100.0 4899.8 4613 100.0 4899.8 9285 100.0 4999.8 7292 100.0 4999.8 4645 100.0 4999.8 9285 3280.8 8280.6 9285 3280.8 8280.6 9285 3280.8 8280.6 9285 2.3.2.1 Shear Modulus and Damping Curves Recent site-specific nonlinear dynamic material properties were not available for Dresden station for sedimentary rocks. The rock material over the upper 500 feet was assumed 1 to have behavior that could be modeled as either linear or non-linear. To represent this potential for either case in the upper 500 feet of sedimentary rock at the Dresden station 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) was assumed 1 to represent an equally plausible alternative rock response across loading level. For the linear analyses, the low strain damping from the EPRI rock curves were used as the constant damping values in the upper 500 feet.

1 Assumptions discussed in Section 2 are provided by EPRI engineers (Reference 15) in accordance with implementation of the SPID (Reference 3) methodology.

Dresden Generating Station Report No.: SL-012190, Revision 1 Correspondence No.: RS-14-067

2.3.2.2 Kappa Base-case kappa estimates were determined using Section B-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 feet of sedimentary rock may be estimated from the averageS-wave velocity over the upper 100 feet (V5100) of the subsurface profile while for a site with less than 3,000 feet of firm rock, kappa may be estimated with a Os of 40 below 500 feet 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 Dresden station site, both conditions, greater as well as less than 3,000 feet of firm rock, were considered within the uncertainty of available inferences in shear-wave velocity. For the shallow depth to hard rock (1 ,000 feet), profiles P1, P2, and P3, the kappa estimates were 0.016s, 0.019s, and 0.007s respectively and resulted in a range considered inadequate to reflect epistemic uncertainty in kappa for the site. To accommodate a larger expression of epistemic uncertainty in kappa, a scale factor of 1.68 (Reference 3) about the kappa estimate of profile P1 was used for profiles P2 and P3 resulting in estimates of 0.027s and 0.009s respectively (Table 2.3.2-3).

For the deep profile (P4, P5 and P6), 5,000 feet to hard rock site conditions, the corresponding average shear-wave velocities (equivalent travel time averaging procedure) over the top 100 feet were 3,702 ftls (P4), 2,962 ftls (P5), and 4,628 ftls (P6).

The corresponding kappa estimates were 0.021s, 0.027s, and 0.016s respectively. As with the shallow Precambrian depth profiles, the range in kappa was considered insufficient and the same scale factor of 1.68 about the mean base-case profile P4 kappa estimate was used resulting in revised estimates of 0.035s and 0.012s for profiles P5 and P6 respectively (Table 2.3.2-3).

Table 2.3.2-3: Kappa values and weights used for site response analyses (Reference 15)

Velocity Profile Kappa(s)

P1 0.016 P2 0.019, 0.027*

P3 0.007, 0.009*

P4 0.021 P5 0.027, 0.035*

P6 0.016, 0.012*

Velocity Profile Weights P1 0.2 P2 0.15 P3 0.15 P4 0.20 P5 0.15 P6 0.15

Denotes revised Kappa based on 1.68 scale factor Dresden Generating Station Report No.: SL-012190, Revision 1 2-13 Correspondence No.: RS-14-067

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 1 shear-wave velocity profiles has been incorporated in the site response calculations.

For the Dresden station site, random shear wave velocity profiles were developed from the base case profiles shown in Figure 2.3.2-1 and Figure 2.3.2-2. Consistent with the discussion in Appendix B of the SPID (Reference 3), the velocity randomization procedure made use of random field models which describe the statistical correlation between layering and shear wave velocity. The default randomization parameters developed in Toro (Reference 17) for 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 feet 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 1 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 (peak ground accelerations (PGA) ranging from 0.01g to 1.50g) were used in the site response analyses. The characteristics of the seismic source and upper crustal attenuation properties assumed 1 for the analysis of the Dresden station 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 Dresden station, 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 Dresden station.

1 Assumptions discussed in Section 2 are provided by EPRI engineers (Reference 15) in accordance with implementation of the SPID (Reference 3} methodology.

Dresden Generating Station Report No.: SL-012190, Revision 1 2-14 Correspondence No.: RS-14-067

2.3.6 Amplification Functions The results of the site response analysis consist of amplification factors (5% critical damped pseudo absolute response spectra) which describe the amplification (or de-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 oscillator 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 the SPID (Reference 3) rock G/Gmax 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 Dresden station firm rock site, Figure 2.3.6-2 shows the corresponding amplification factors developed with linear site response analyses (model M2). Between the linear and nonlinear (equivalent-linear) analyses, Figure 2.3.6-1 and Figure 2.3.6-2 respectively show only a minor difference for frequencies below about 20Hz and the 0.5g loading level and below. Above about the 0.5g loading level, the differences increase significantly but only above about 20 Hz. Tabulated values of amplification factors are provided in Tables A-2b1 and A-2b2 in Appendix A.

Dresden Generating Station Report No.: SL-012190, Revision 1 2-15 Correspondence No.: RS-14-067

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AMPLIFICATION, DRESDEN, M1P1K1 M6.5, 1 CORNER: PAGE 1 OF Z Figure 2.3.6~1: Example suite of amplification factors (5% 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 (K1) 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) {Reference 15)

Dresden Generating Station 2~16 Report No.: SL-012190, Revision 1 Correspondence No.: RS-14-067

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AMPLIFICATION, DRESDEN, M1P1K1 M 6.5, 1 CORNER: PAGE Z OF Z Figure 2.3.6-1: (Continued)

Dresden Generating Station Report No.: SL-012190, Revision 1 2-17 Correspondence No.: RS-14-067

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AMPLIFICATION, DRESDEN, M2P1K1 M 6.5 1 1 CORNER; PAGE 1 Of Z Figure 2.3.6-2: Example suite of amplification factors (5% critical damping pseudo absolute acceleration spectra) developed for the mean base-case profile (P1 ), linear site response (model M2), and base-case kappa (K1) 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)

(Reference 15)

Dresden Generating Station Report No.: SL-012190, Revision 1 Correspondence No.: RS-14-067

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AMPLIFICATION, DRESDEN, M2P1K1 M 6.5, 1 CORNER: PRGE 2 Of 2 Figure 2.3.6-2: (Continued)

Dresden Generating Station Report No.: SL-012190, Revision 1 2-19 Correspondence No.: RS-14-067

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 B-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 amplitude-dependent amplification functions (median values and standard deviations) developed and described in the previous section. The resulting control point mean hazard curves for Dresden station 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.

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Figure 2.3. 7-1: Control point mean hazard curves for spectral frequencies of 0.5, 1, 2.5, 5, 10, 25 and 100Hz (PGA) at Dresden station (5% of critical damping)

Dresden Generating Station Report No.: SL-012190, Revision 1 2-20 Correspondence No.: RS-14-067

2.4 CONTROL POINT RESPONSE SPECTRA The control point hazard curves described above have been used to develop uniform hazard response spectra (UHRS) and the ground motion response spectrum (GMRS).

The UHRS were obtained through linear interpolation in log-log space to estimate the spectral acceleration at each spectral frequency for the 1E-4 and 1E-5 per year hazard levels.

The 1E-4 and 1E-5 UHRS, along with a design factor {OF), are used to compute the GMRS at the control point using the criteria in Regulatory Guide 1.208 {Reference 18).

Table 2.4-1 shows the UHRS and GMRS accelerations for a range of spectral frequencies.

Table 2.4-1: UHRS and GMRS for Dresden, 5% of critical damping

{Reference 15) 1o* UHRS (g) 4 5 Freq. {Hz} 10 UHRS (g) GMRS (g) 100 1.63E-01 5.17E-01 2.46E-01 90 1.63E-01 5.22E-01 2.48E-01 80 1.65E-01 5.29E-01 2.51 E-01 70 1.67E-01 5.42E-01 2.57E-01 60 1.74E-01 5.69E-01 2.69E-01 50 1.89E-01 6.26E-01 2.96E-01 40 2.14E-01 7.18E-01 3.38E-01 35 2.33E-01 7.83E-01 3.69E-01 30 2.66E-01 8.95E-01 4.22E-01 25 3.19E-01 1.07E+OO 5.04E-01 20 3.70E-01 1.22E+OO 5.77E-01 15 3.83E-01 1.24E+OO 5.87E-01 12.5 3.80E-01 1.21E+OO 5.77E-01 10 3.56E-01 1.12E+OO 5.34E-01 9 3.34E-01 1.04E+OO 4.99E-01 8 3.14E-01 9.70E-01 4.65E-01 7 2.93E-01 8.98E-01 4.31E-01 6 2.67E-01 8.08E-01 3.89E-01 5 2.39E-01 7.12E-01 3.43E-01 4 1.90E-01 5.48E-01 2.66E-01 3.5 1.65E-01 4.65E-01 2.27E-01 3 1.38E-01 3.80E-01 1.86E-01 2.5 1.16E-01 3.09E-01

1.52E-01 2 1.10E-01 2.83E-01 1.41E-01 1.5 1.05E-01 2.55E-01 1.28E-01 1.25 1.03E-01 2.41E-01 1.22E-01 1 9.43E-02 2.11E-01 1.08E-01 Dresden Generating Station Report No.: SL-012190, Revision 1 2-21 Correspondence No.: RS-14-067

Table 2A-1: (Continued) 4 Freq. (Hz) 10 UHRS {g) 1O.s UHRS (g) GMRS (g) 0.9 9.00E-02 2.01 E-01 1.03E-01 0.8 8.49E-02 1.90E-01 9.71E-02 0.7 7.66E-02 1.72E-01 8.78E-02 0.6 6.83E-02 1.53E-01 7.82E-02 0.5 5.99E-02 1.35E-01 6.87E-02 0.4 4.80E-02 1.08E-01 5.49E-02 0.35 4.20E-02 9.42E-02 4.81E-02 0.3 3.60E-02 8.07E-02 4.12E-02 0.25 3.00E-02 6.73E-02 3.43E-02 0.2 2.40E-02 5.38E-02 2.75E-02 0.15 1.80E-02 4.04E-02 2.06E-02 0.125 1.50E-02 3.36E-02 1.72E-02 0.1 1.20E-02 2.69E-02 1.37E-02 The 1E-4 and 1E-5 UHRS are used to compute the GMRS at the control point and are shown in Figure 2.4-1.

Mean Soil UHRS and GMRS at Dresden

-1E-5 UHRS

-GMRS

-1E-4 UHRS 0.1 1 10 100 Spectral frequency, Hz Figure 2.4-1: Plots of 1E-4 and 1E-5 UHRS and GMRS at control point for Dresden, 5% critical damping (Reference 15)

Dresden Generating Station Report No.: SL-012190, Revision 1 2-22 Correspondence No.: RS-14-067

3 Plant Design Basis Ground Motion The design basis for Dresden station is identified in the Updated Final Safety Analysis Report (Reference 10). The SSE for the site was based on the seismology report in Volume Ill, Section 4 of the Dresden Unit 2 PDAR. An earthquake having a MMI VII was considered the maximum anticipated seismic event for the site. A safe shutdown earthquake having a ground acceleration of 0.2g was selected based on the seismological reviews.

3.1 SSE DESCRIPTION OF SPECTRAL SHAPE The input motions used to create the seismic design of Dresden station are based on the Hausner ground response spectrum and the north-south component of the El Centro earthquake of May 18, 1940. The Dresden design basis SSE ground spectrum is the Hausner spectrum normalized to a peak ground acceleration (PGA) of 0.2g. Equipment analyzed using the response spectrum method used the Hausner design spectra. The El Centro 1940 earthquake, N-S component anchored to 0.1 Og was used to perform time history analysis of selected structures and equipment and to generate the in-structure response spectra. The SSE is defined by multiplying the OBE acceleration by a factor of two resulting in a horizontal direction PGA value of 0.20g. Table 3.1-1 shows the spectral acceleration values as a function of frequency for the 5% damped horizontal SSE. The SSE is plotted in Figure 3.1-1. {Reference 10)

Table 3.1-1: Dresden Safe Shutdown Earthquake ground response spectrum, 5% critical damping (Reference 24)

Frequency (Hz) Spectral Acceleration {g) 1.14 0.200 1.25 0.220 1.43 0.246 1.67 0.270 2.00 0.290 2.50 0.310 3.33 0.328 4.00 0.332 4.44 0.332 5.00 0.330 6.67 0.320 10.0 0.300 11.1 0.292 12.5 0.284 14.3 0.276 Dresden Genemting Station Report No.: SL-012190, Revision 1 3-1 Correspondence No.: RS-14-067

Table 3.1-1: {Continued)

Frequency (Hz) Spectral Acceleration (g) 16.7 0.266 20.0 0.256 25.0 0.246 28.6 0.240 33.3 0.234 40.0 0.226 50.0 0.218 66.7 0.21 100 0.20 Dresden SSE Horizontal Ground Response Spectrum

§

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Figure 3.1-1: Dresden SSE horizontal ground response spectrum, 5% critical damping Dresden Generating Station Report No.: SL-012190, Revision 1 3-2 Correspondence No.: RS-14-067

3.2 CONTROL POINT ELEVATION Dresden was designed and constructed before the concept of control point was defined, and the UFSAR (Reference 10) does not provide specific definition of the SSE control point. Therefore, the SPID (Reference 3) Section 2.4.2 criteria were used to determine the appropriate control point elevation. The Dresden site has a thin layer of topsoil overlaying the bedrock layer. This thin layer was removed before founding the Dresden safety-related structures. For rock sites, the SPID (Reference 3) guidance recommends to define the control point at the top of the rock. Therefore, the control point is elevation 515 feet MSL, which is the approximate top of the bedrock in the vicinity of the main power block.

Dresden Generating Station Report No.: SL-012190, Revision 1 Correspondence No.: RS-14-067

4 Screening Evaluation Following completion of the seismic hazard reevaluation, as requested in the 50.54(f) letter (Reference 1}, a screening process is required to determine if a risk evaluation is needed. The horizontal GMRS determined from the hazard reevaluation is used to characterize the amplitude of the new seismic hazard at each of the nuclear power plant sites. The screening evaluation compares the GMRS with the established plant-level seismic capacity, in accordance with the SPID, Section 3 (Reference 3}.

4.1 RISK EVALUATION SCREENING (1 TO 10Hz)

In the 1 Hz to 10 Hz part of the response spectrum, the GMRS exceeds the SSE.

Therefore, Dresden station screens in for a risk evaluation.

Further, in accordance with the screening requirements in the ESEP Guidance (Reference 4}, Dresden Station will perform "Augmented Approach" near-term seismic evaluations. The ESEP will be performed as an interim assessment for Dresden station.

See Section 5.1 for further details on the ESEP.

4.2 HIGH FREQUENCY SCREENING (> 10 Hz)

The GMRS exceeds the SSE in the range above 10 Hz. Therefore, high frequency exceedances can be addressed in the risk evaluation discussed in Section 4.1.

Section 3.4 of the SPID (Reference 3) discusses high-frequency exceedances. It discusses the impact of high-frequency ground motion on plant components and identifies the component groups that are sensitive to high-frequency vibration. A two-phase test program is described, which is currently ongoing, that will develop data to support the high-frequency evaluation.

The SPID concludes that high-frequency vibration is not damaging, in general, to components with strain- or stress-based failure modes, based on EPRI Report NP-7498 (Reference 27). But components, such as relays, subject to electrical functionality failure modes have unknown acceleration sensitivity for frequencies above 16Hz.

Dresden Generating Station Report No.: SL-012190. Revision 1 4-1 Correspondence No.: RS-14-067

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. EPRI Report 1015109 (Reference 26) provides guidance for identifying and evaluating potentially high-frequency sensitive components.

Guidance from these documents is considered in the SPID (Reference 3) report for identifying components that are sensitive to high-frequency vibration. Component types listed in Table 2-1 of the EPRI Report 3002000706 (Reference 36) will require high-frequency evaluation. Those component types 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 10Hz)

In the 1 Hz to 10 Hz part of the response spectrum, the GMRS exceeds the SSE.

Therefore, a spent fuel pool evaluation will be performed.

Dresden Generating Station Report No.: SL-012190, Revision 1 4-2 Correspondence No.: RS-14-067

5 Interim Actions Based on the screening evaluation outcome described in Section 4, the GMRS exceeds the SSE at frequencies from 1 Hz to 10 Hz and greater than 10 Hz. Therefore, Dresden station screens in for a risk evaluation in response to the 50.54(f) letter request for information (Reference 1). Prior to completion of the risk evaluation, Dresden station will implement certain interim actions to ensure continued and improved seismic safety of the plant, namely execution of the Expedited Seismic Evaluation Process (ESEP).

5.1 EXPEDITED SEISMIC EVALUATION PROCESS Based on the screening evaluation, the expedited seismic evaluation described in EPRI Report 3002000704 (Reference 4) will be performed as proposed in a letter to the NRC dated April 9, 2013 (Reference 6) and agreed to by the NRC in the letter dated May 7, 2013 (Reference 29).

The ESEP addresses the 50.54(f) letter (Reference 1) request for "interim evaluations and actions taken or planned to address the higher seismic hazard relative to the design basis, as appropriate, prior to completion of the risk evaluation." Specifically, the ESEP focuses initial industry efforts on short term evaluations that will lead to prompt modifications to some of the most important components that could improve plant seismic safety.

5.2 INTERIM EVALUATION OF SEISMIC HAZARD Consistent with the NRC letter dated February 20, 2014 (Reference 32), the seismic hazard reevaluations presented herein are distinct from the current design and licensing bases of Dresden station. Therefore, the results do not call into question the operability or functionality of SSCs and are not reportable pursuant to 10 CFR 50.72, "Immediate notification requirements for operating nuclear power reactors" (Reference 37), and 10 CFR 50.73, "Licensee event report system" (Reference 38).

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, NEI letter dated March 12, 2014 (Reference 33), provides seismic core damage risk estimates using the updated seismic hazards for the operating nuclear plants in the Central and Eastern United States. These risk estimates continue to support the following conclusions of the NRC Gl-199 Safety/Risk Assessment (Reference 34):

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 Gl-199 Safety/Risk Assessment, based in part on information from the U. S. Nuclear Regulatory Commission's (NRC's)

Dresden Generating Station Report No.: SL-012190, Revision 1 5-1 Correspondence No.: RS-14-067

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.

Dresden station is included in the March 12, 2014 risk estimates (Reference 33). Using the methodology described in the NEiletter, all plants were shown to be below 10-4/year; thus, the above conclusions apply.

5.3 SEISMIC WALKDOWN INSIGHTS In response to NTTF Recommendation 2.3, the 50.54(f) letter (Reference 1) 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. Seismic walkdown guidance (EPRI1025286, Reference 21) was developed and endorsed by the NRC as a means for all plants to provide a uniform and acceptable industry response to NTTF 2.3 seismic walkdowns.

Seismic walkdowns in response to NTTF 2.3 for Dresden station have been performed as documented in References 12 and 13. The seismic walkdowns for Dresden station determined that no adverse anchorage conditions, no adverse seismic spatial interactions, and no other adverse seismic conditions existed for equipment examined during the walkdowns. Any potentially degraded, non-conforming, or unanalyzed conditions identified during the seismic walkdown program were assessed in accordance with the plant corrective action program, and were identified as being minor issues.

Plant improvements and "outliers" identified in the Dresden station seismic Individual Plant Examination of External Events (lPEEE) (References 11 and 20) were reviewed as part of the seismic walkdowns (References 12 and 13). Plant improvements were identified in Sections 3 and 7 of the IPEEE (Reference 11 ). Table G-1 of Appendix G of the seismic walkdown reports (12 and 13) lists the plant improvements, the IPEEE proposed resolution, the actual resolution, and resolution date. The seismic walkdown reports confirmed that no open items exist from the seismic portion of the IPEEE program (References 12 and 13).

5.4 BEYOND-DESIGN-BASIS SEISMIC INSIGHTS A beyond-design-basis seismic margin assessment (SMA) was performed for the seismic portion of the Dresden station IPEEE using the EPRI SMA methodology, EPRI NP-6041-SL (Reference 9) with the enhancements identified in NUREG-1407 (Reference 22), where applicable (References 11 and 20). Dresden is a focused scope 0.3g peak ground acceleration (PGA) plant per NUREG-1407 (Reference 22). The review level earthquake (RLE) was a NUREG/CR-0098 (Reference 31) rock spectrum anchored to 0.3g PGA (References 11 and 20).

Dresden Generating Station Report No.: SL-012190, Revision 1 5-2 Correspondence No.: RS-14-067

The majority of components on the IPEEE Success Path Equipment List (SPEL) had capacities greater than or equal to the RLE (0.3g PGA), which demonstrates seismic capacity beyond the design basis. However, there were some items with HCLPFs less than the RLE. The controlling High Confidence of a Low Probability of Failure (HCLPF) component capacity reported was 0.2g PGA (References 11 and 20). Therefore, the IPEEE HCLPF spectrum (IHS) is a NUREG/CR-0098 (Reference 31) rock spectrum anchored to 0.2g PGA.

The Dresden station IPEEE SMA did not identify any overall seismic concerns. The IPEEE submittal report (Attachment 1 of Reference 20) concludes that Dresden plant has reasonable margin with respect to its design basis earthquake based on experience with actual industrial facilities in moderate to severe earthquakes.

Dresden Generating Station Report No.: SL-012190, Revision 1 5-3 Correspondence No.: RS-14-067

6 Conclusions In accordance with the 50.54(f) letter (Reference 1), a seismic hazard and screening evaluation was performed for the Dresden Generating Station. This reevaluation followed the SPID guidance (Reference 3) in order to develop a GMRS for the site. The GMRS was developed solely for the purpose of screening for additional evaluation requirements in accordance with the SPID (Reference 3). The new GMRS represents a beyond-design-basis seismic demand and does not constitute a change in the plant design or licensing basis.

The screening evaluation comparison demonstrates that the GMRS exceeds the SSE in the 1 Hz to 10Hz range of the response spectrum and also above 10 Hz. Based on the screening evaluation, Dresden station screens in for a risk evaluation and a spent fuel pool integrity evaluation. The risk evaluation process can also evaluate components for high frequency exceedances (> 10 Hz). The risk evaluation schedule will be in accordance with NRC prioritization and the NEI Jetter dated April 9, 2013 (Reference 6) as endorsed by the NRC in the letter to NEI dated May 7, 2013 (Reference 29).

The near-term ESEP interim evaluations will also be performed following the ESEP guidance (Reference 4). This is an interim action to establish beyond-design-basis safety margin prior to completion of the risk evaluation. ESEP evaluation will be performed and modifications (if required) will be implemented on a schedule in accordance with the NEI letter dated April 9, 2013 (Reference 6) as endorsed by the NRC in the letter to NEI dated May 7, 2013 (Reference 29).

Dresden Generating Station Report No.: SL-012190, Revision 1 6-1 Correspondence No.: RS-14-067

7 References

1. NRC Letter (E. J. Leeds) to All Power Reactor Licensees and Holders of Construction Permits in Active or Deferred Status, 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, March 2012

2. NRC Regulations Title 10, Code of Federal Regulations, Part 50, "Domestic Licensing of Production and Utilization Facilities"

3. EPRI Technical Report 1025287, Seismic Evaluation Guidance: Screening, Prioritization and Implementation Details (SPID) for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1: Seismic, dated February 2013

4. 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

5. NRC Regulations Title 10, Code of Federal Regulations, Part 100, "Reactor Site Criteria"

6. NEI Letter (A. R. Pietrangelo) to the NRC, Proposed Path Forward for NTTF Recommendation 2.1: Seismic Reevaluations, April9, 2013

7. EPRI Technical Report 1021097 (NUREG-2115), Central and Eastern United States Seismic Source Characterization for Nuclear Facilities, dated January 2012

8. EPRI Technical Report 3002000717, EPRI (2004, 2006) Ground-Motion Model (GMM) Review Project, dated June 2013

9. EPRI NP-6041-SL, A Methodology for Assessment of Nuclear Power Plant Seismic Margin (Revision 1), dated August 1991

10. Dresden Power Station Updated Final Safety Analysis Report (UFSAR),

Revision 10, June 2013

11. Exelon, Dresden Nuclear Power Station Units 2 and 3, Individual Plant Examination of External Events for Severe Accident Vulnerabilities, December 30, 1997

12. Seismic Walkdown Report in Response to the 50.54(f) Information Request Regarding Fukushima Near-Term Task Force Recommendation 2.3: Seismic for the Dresden Generating Station Unit 2, Exelon Correspondence No. RS-12-167, Enclosure 1, November 27, 2012 Dresden Generating Station Report No.: SL-012190, Revision 1 7-1 Correspondence No.. RS-14-067

13. Seismic Walkdown Report in Response to the 50.54(f) Information Request Regarding Fukushima Near-Term Task Force Recommendation 2.3: Seismic for the Dresden Generating Station Unit 3, Exelon Correspondence No. RS-12-167, Enclosure 2, November 27, 2012

14. SGH (2012). Review of Existing Site Response Parameter Data for the Exelon Nuclear Fleet-Revision 1, Simpson Gumpertz & Heger Report No. 128018-R-01, dated July 17, 2012, transmitted by letter from J. Clark to J. Hamel on July 18, 2012

15. EPRI RSM-121313-031, LCI Report: Dresden Seismic Hazard and Screening Report, December 23, 2013

16. Dames & Moore, Dresden Unit 1 ISFSI Pad Study, Calc No. DRE98-0096, Attachment B

17. Silva, W.J., N. Abrahamson, G. Toro and C. Costantio, 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

18. NRC Regulatory Guide 1.208, A Performance-Based Approach to Define the Site-Specific Earthquake Ground Motion, March 2007

19. General Electric Company, Dresden Plant Design Analysis Report (PDAR),

Volume Ill, Site and Environs

20. CornEd PSLTR #00-0068, Request for Additional Information Regarding Individual Plant Examination of External Events, March 30, 2000

21. EPRI Technical Report 1025286, Seismic Walkdown Guidance for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Seismic, June 2012

22. NRC NUREG-1407, Procedural and Submittal Guidance for the Individual Plant Examination of External Events (IPEEE) for Severe Accident Vulnerabilities, April1991

23. 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-13-102, dated April29, 2013

24. TDBD-DQ-1, Topical Design Basis Document Quad Cities Units 1 & 2 and Dresden Units 2 & 3 Structural Design Criteria, Revision 1, April 2000

25. EPRI Report 1015108, Program on Technology Innovation: The Effects of High-Frequency Ground Motion on Structures, Components and Equipment in Nuclear Power Plants, June 2007

26. EPRI Report 1015109, Program on Technology Innovation: Seismic Screening of Components Sensitive to High-Frequency Vibratory Motions, October 2007 Dresden Generating Station Report No.: SL-012190, Revision 1 7-2 Correspondence No.: RS-14-067

27. EPRI NP-7498, Industry Approach to Severe Accident Policy Implementation, November, 1991

28. Attachment 4 to Letter from Glen T. Kaegi of Exelon to U.S. Nuclear Regulatory Commission, Dresden Nuclear Power Station, Units 2 and 3, Descriptions of Subsurface Materials and Properties and Base Case Velocity Profiles, dated September 12, 2013 (Exelon correspondence numbers RS-13-205, RA-13-075, and TMI-13-1 04)

29. NRC (E. Leeds) Letter to NEI (J. Pollock), ML13106A331, 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, 2013, Information Request for Seismic Reevaluations, dated May 7, 2013

30. NRC Letter, Endorsement of EPRI Final Draft Report 1025287, Seismic Evaluation Guidance, dated February 15, 2013

31. NRC NUREG/CR-0098, Development of Criteria for Seismic Review of Selected Nuclear Power Plants, May 1978

32. NRC Letter (E. J. Leeds) to All Power Reactor Licensees and Holders of Construction Permits in Active or Deferred Status, 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-lchi Accident, dated February 20, 2014

33. NEI Letter (A. R. Pietrangelo) to the NRC, Seismic Risk Evaluations for Plants in the Central and Eastern United States, March 12, 2014

34. NUREG-0933, "A Prioritization of Generic Safety Issues," Supplement 34, "Resolution of Generic Safety Issues," Issue 199: Implications of Updated Probabilistic Seismic Hazard Estimates in Central and Eastern United States on Existing Plants, Revision 1, September, 2011

35. E-mail from R. Kassawara (EPRI) to J. Clark (Exelon) dated February 27, 2014,

Subject:

Amp Tables

36. EPRI Report 3002000706, High Frequency Program, Phase 1 Seismic Test Summary, September 2013

37. Title 10 Code of Federal Regulations Part 50 Section 72, "Immediate notification requirements for operating nuclear power reactors"

38. Title 10 Code of Federal Regulations Part 50 Section 73, "Licensee event report system" Dresden Generating Station Report No.: SL-012190, Revision 1 7-3 Correspondence No.: RS-14-067

A Additional Tables Table A-1a: Mean and fractile seismic hazard curves for 100Hz (PGA) at Dresden, 5% of critical damping (Reference 15)

AMPS(g) MEAN 0.05 0.16 0.50 0.84 0.95 0.0005 6.90E-02 3.37E-02 4.98E-02 6.93E-02 8.85E-02 9.93E-02 0.001 4.98E-02 2.07E-02 3.28E-02 4.90E-02 6.73E-02 B.OOE-02 0.005 1.38E-02 5.12E-03 7.89E-03 1.25E-02 1.87E-02 2.80E-02 0.01 6.87E-03 2.25E-03 3.47E-03 6.00E-03 9.51E-03 1.57E-02 0.015 4.26E-03 1.27E-03 1.92E-03 3.52E-03 6.09E-03 1.07E-02 0.03 1.60E-03 3.73E-04 5.66E-04 1.13E-03 2.32E-03 4.98E-03 0.05 7.21E-04 1.32E-04 2.16E-04 4.63E-04 1.05E-03 2.35E-03 0.075 3.75E-04 6.00E-05 1.02E-04 2.32E-04 5.66E-04 1.20E-03 0.1 2.32E-04 3.42E-05 6.09E-05 1.42E-04 3.57E-04 7.45E-04 0.15 1.16E-04 1.51 E-05 2.84E-05 7.03E-05 1.82E-04 3.73E-04 0.3 3.19E-05 2.92E-06 6.45E-06 1.87E-05 5.12E-05 1.05E-04 0.5 1.08E-05 6.64E-07 1.67E-06 6.00E-06 1.82E-05 3.68E-05 0.75 4.17E-06 1.62E-07 4.77E-07 2.10E-06 7.13E-06 1.49E-05

1. 2.00E-06 5.20E-08 1.77E-07 9.11 E-07 3.47E-06 7.45E-06 1.5 6.53E-07 8.72E-09 3.73E-08 2.46E-07 1.13E-06 2.57E-06

3. 7.38E-08 2.92E-10 1.60E-09 1.72E-08 1.16E-07 3.23E-07

5. 1.15E-08 1.11 E-10 1.79E-10 1.62E-09 1.55E-OB 5.12E-08 7.5 2.18E-09 9.11E-11 1.11E-10 2.64E-10 2.53E-09 9.79E-09

10. 6.06E-10 8.12E-11 9.37E-11 1.23E-10 6.73E-10 2.72E-09 Dresden Generating Station Report No.: SL-012190, Revision 1 A-1 Correspondence No.: RS-14-067

Table A-1 b: Mean and fractile seismic hazard curves for 25 Hz at Dresden, 5% of critical damping (Reference 15)

AMPS(g) MEAN 0.05 0.16 0.50 0.84 0.95 0.0005 7.52E-02 4.37E-02 5.66E-02 7.55E-02 9.37E-02 9.93E-02 0.001 5.84E-02 2.88E-02 4.07E-02 5.83E-02 7.66E-02 B.BSE-02 0.005 2.01E-02 B.OOE-03 1.16E-02 1.84E-02 2.76E-02 3.95E-02 0.01 1.10E-02 3.90E-03 5.75E-03 9.65E-03 1.53E-02 2.32E-02 0.015 7.33E-03 2.35E-03 3.52E-03 6.26E-03 1.05E-02 1.62E-02 0.03 3.30E-03 7.89E-04 1.25E-03 2.60E-03 5.12E-03 8.35E-03 0.05 1.69E-03 3.01E-04 5.20E-04 1.21E-03 2.68E-03 4.77E-03 0.075 9.57E-04 1.46E-04 2.60E-04 6.54E-04 1.51E-03 2.80E-03 0.1 6.28E-04 9.11E-05 1.64E-04 4.19E-04 9.93E-04 1.84E-03 0.15 3.39E-04 4.77E-05 8.72E-05 I 2.19E-04 5.42E-04 1.01 E-03 0.3 1.11E-04 1.53E-05 2.84E-05 7.13E-05 1.82E-04 3.33E-04 0.5 4.55E-05 5.91E-06 1.13E-05 2.92E-05 7.55E-05 1.36E-04 0.75 2.10E-05 2.53E-06 4.98E-06 1.32E-05 3.57E-05 6.45E-05

1. 1.16E-05 1.29E-06 2.64E-06 7.13E-06 2.01E-05 3.68E-05 1.5 4.73E-06 4.43E-07 9.51E-07 2.76E-06 8.35E-06 1.55E-05

3. 8.24E-07 4.70E-08 1.16E-07 4.13E-07 1.46E-06 2.96E-06

5. 1.91E-07 5.66E-09 1.74E-08 8.23E-08 3.37E-07 7.34E-07 7.5 5.38E-08 8.23E-10 3.05E-09 1.98E-08 9.37E-08 2.19E-07

10. 2.08E-08 2.32E-10 8.12E-10 6.54E-09 3.52E-08 8.98E-08 Dresden Generating Station Report No.: Sl-012190, Revision 1 A-2 Correspondence No.: RS-14-067

Table A-1c: Mean and fractile seismic hazard curves for 10Hz at Dresden, 5% of critical damping (Reference 15)

AMPS(g) MEAN 0.05 0.16 0.50 0.84 0.95 0.0005 8.48E-02 5.83E-02 6.64E-02 8.47E-02 9.93E-02 9.93E-02 0.001 7.18E-02 4.50E-02 5.35E-02 7.13E-02 8.98E-02 9.93E-02 0.005 2.83E-02 1.34E-02 1.79E-02 2.72E-02 3.84E-02 4.83E-02 0.01 1.54E-02 6.73E-03 9.24E-03 1.44E-02 2.13E-02 2.80E-02 0.015 1.04E-02 4.25E-03 5.91E-03 9.51E-03 1.44E-02 1.95E-02 0.03 4.81E-03 1.69E-03 2.42E-03 4.25E-03 7.03E-03 1.01 E-02 0.05 2.49E-03 7.77E-04 1.13E-03 2.04E-03 3.73E-03 5.83E-03 0.075 1.38E-03 3.90E-04 5.75E-04 1.08E-03 2.07E-03 3.52E-03 0.1 8.85E-04 2.29E-04 3.52E-04 6.73E-04 1.32E-03 2.32E-03 0.15 4.57E-04 1.07E-04 1.69E-04 3.42E-04 6.93E-04 1.21E-03 0.3 1.37E-04 2.72E-05 4.70E-05 1.02E-04 2.16E-04 3.68E-04 0.5 5.33E-05 9.11E-06 1.69E-05 3.95E-05 8.72E-05 1.46E-04 0.75 2.38E-05 3.47E-06 6.93E-06 1.72E-05 3.95E-05 6.64E-05

1. 1.29E-05 1.64E-06 3.37E-06 9.11E-06 2.19E-05 3.73E-05 1.5 5.11E-06 4.83E-07 1.08E-06 3.37E-06 8.98E-06 1.57E-05

3. 8.49E-07 3.63E-08 1.01E-07 4.50E-07 1.53E-06 3.01E-06

5. 1.87E-07 3.37E-09 1.16E-08 7.77E-08 3.37E-07 7.34E-07 7.5 4.94E-08 4.37E-10 1.67E-09 1.57E-08 8.60E-08 2.10E-07

10. 1.78E-08 1.49E-10 4.19E-10 4.63E-09 2.96E-08 7.77E-08 Dresden Generating Station Report No.: SL-012190, Revision 1 A-3 Correspondence No.: RS-14-067

Table A-1d: Mean and fractile seismic hazard curves for 5Hz at Dresden, 5% of critical damping (Reference 15)

AMPS(g) MEAN 0.05 0.16 0.50 0.84 0.95 0.0005 8.62E-02 6.00E-02 6.73E-02 8.60E-02 9.93E-02 9.93E-02 0.001 7.40E-02 4.56E-02 5.58E-02 7.34E-02 9.24E-02 9.93E-02 0.005 2.88E-02 1.32E-02 1.77E-02 2.76E-02 4.07E-02 4.77E-02 0.01 1.48E-02 6.45E-03 8.98E-03 1.40E-02 2.10E-02 2.57E-02 0.015 9.49E-03 3.95E-03 5.66E-03 8.98E-03 1.34E-02 1.67E-02 0.03 3.99E-03 1.46E-03 2.13E-03 3.63E-03 5.83E-03 7.77E-03 0.05 1.85E-03 6.00E-04 8.85E-04 1.57E-03 2.76E-03 4.13E-03 0.075 9.26E-04 2.76E-04 4.13E-04 7.45E-04 1.34E-03 2.25E-03 0.1 5.48E-04 1.55E-04 2.35E-04 4.31E-04 7.89E-04 1.38E-03 0.15 2.53E-04 6.54E-05 1.02E-04 1.95E-04 3.73E-04 6.54E-04 0.3 6.36E-05 1.40E-05 2.39E-05 4.98E-05 1.01E-04 1.62E-04 0.5 2.19E-05 4.25E-06 7.66E-06 1.72E-05 3.57E-05 5.58E-05 0.75 8.92E-06 1.46E-06 2.84E-06 6.83E-06 1.46E-05 2.39E-05

1. 4.53E-06 6.45E-07 1.31 E-06 3.33E-06 7.55E-06 1.25E-05 1.5 1.64E-06 1.79E-07 3.90E-07 1.11E-06 2.80E-06 4.90E-06

3. 2.34E-07 1.29E-08 3.33E-08 1.27E-07 4.07E-07 8.12E-07

5. 4.60E-08 1.27E-09 3.84E-09 1.92E-08 7.77E-08 1.82E-07 7.5 1.11 E-08 2.19E-10 6.00E-10 3.52E-09 1.79E-08 4.70E-08

10. 3.75E-09 1.15E-10 1.95E-10 9.79E-10 5.66E-09 1.64E-08 Dresden Generating Station Report No.: SL-012190, Revision 1 A-4 Correspondence No.: RS-14-067

Table A-1e: Mean and fractile seismic hazard curves for 2.5 Hz at Dresden, 5% of critical damping (Reference 15)

AMPS(g) MEAN 0.05 0.16 0.50 0.84 0.95 0.0005 7.82E-02 5.05E-02 6.00E-02 7.77E-02 9.65E-02 9.93E-02 0.001 6.07E-02 3.37E-02 4.19E-02 5.91E-02 S.OOE-02 9.24E-02 0.005 1.75E-02 7.89E-03 1.07E-02 1.64E-02 2.49E-02 3.05E-02 0.01 8.16E-03 3.42E-03 4.83E-03 7.66E-03 1.15E-02 1.46E-02 0.015 4.97E-03 1.90E-03 2.76E-03 4.63E-03 7.23E-03 9.24E-03 0.03 1.80E-03 5.27E-04 B.OOE-04 1.51 E-03 2.80E-03 4.07E-03 0.05 6.84E-04 1.67E-04 2.64E-04 5.20E-04 1.07E-03 1.79E-03 0.075 2.79E-04 6.17E-05 1.01E-04 2.04E-04 4.31E-04 7.77E-04 0.1 1.42E-04 2.96E-05 4.98E-05 1.02E-04 2.22E-04 3.95E-04 0.15 5.38E-05 1.04E-05 1.79E-05 3.90E-05 8.72E-05 1.49E-04 0.3 1.07E-05 1.55E-06 3.01E-06 7.45E-06 1.79E-05 3.09E-05 0.5 3.25E-06 3.33E-07 7.23E-07 2.10E-06 5.58E-06 1.01E-05 0.75 1.22E-06 8.72E-08 2.10E-07 7.03E-07 2.10E-06 4.07E-06

1. 5.86E-07 3.09E-08 8.12E-08 3.09E-07 1.02E-06 2.07E-06 1.5 1.97E-07 6.17E-09 1.87E-08 8.72E-08 3.42E-07 7.55E-07

3. 2.44E-08 3.23E-10 1.08E-09 7.13E-09 3.95E-08 1.05E-07

5. 4.20E-09 1.11E-10 1.64E-10 8.60E-10 6.09E-09 1.90E-08 7.5 8.89E-10 9.11E-11 1.11E-10 1.95E-10 1.18E-09 4.01E-09

10. 2.70E-10 8.12E-11 9.24E-11 1.15E-10 3.79E-10 1.29E-09 Dresden Generating Station Report No.: SL-012190, Revision 1 A-5 Correspondence No.: RS-14-067

Table A-1f: Mean and fractile seismic hazard curves for 1 Hz at Dresden, 5% of critical damping (Reference 15)

AMPS(g) MEAN 0.05 0.16 0.50 0.84 0.95 0.0005 5.86E-02 2.84E-02 3.84E-02 5.83E-02 7.89E-02 9.11E-02 0.001 3.94E-02 1.60E-02 2.35E-02 3.79E-02 5.50E-02 6.73E-02 0.005 9.84E-03 3.52E-03 5.35E-03 9.11E-03 1.42E-02 1.87E-02 0.01 4.85E-03 1.40E-03 2.32E-03 4.43E-03 7.34E-03 9.79E-03 0.015 3.10E-03 7.03E-04 1.25E-03 2.72E-03 4.98E-03 6.83E-03 0.03 1.21E-03 1.64E-04 3.23E-04 8.72E-04 2.13E-03 3.37E-03 0.05 4.68E-04 4.56E-05 9.24E-05 2.80E-04 8.23E-04 1.53E-03 0.075 1.83E-04 1.46E-05 3.05E-05 9.65E-05 3.09E-04 6.45E-04 0.1 8.57E-05 6.26E-06 1.32E-05 4.19E-05 1.38E-04 3.09E-04 0.15 2.68E-05 1.79E-06 3.90E-06 1.27E-05 4.25E-05 9.65E-05 0.3 3.59E-06 1.84E-07 4.50E-07 1.60E-06 6.00E-06 1.36E-05 0.5 9.42E-07 3.05E-08 8.47E-08 3.68E-07 1.55E-06 3.84E-06 0.75 3.44E-07 6.45E-09 2.10E-08 1.10E-07 5.50E-07 1.49E-06

1. 1.67E-07 2.01E-09 7.23E-09 4.50E-08 2.57E-07 7.55E-07 1.5 5.74E-08 4.07E-10 1.46E-09 1.13E-08 8.12E-08 2.68E-07

3. 7.63E-09 1.11E-10 1.46E-10 8.23E-10 8.35E-09 3.52E-08

5. 1.41E-09 9.11E-11 1.11E-10 1.60E-10 1.23E-09 6.17E-09 7.5 3.23E-10 8.12E-11 9.11E-11 1.11E-10 2.84E-10 1.34E-09

10. 1.05E-10 8.12E-11 9.11E-11 1.11E-10 1.40E-10 4.56E-10 Dresden Generating Station Report No.: SL-012190, Revision 1 A-6 Correspondence No.: RS-14..067

Table A-1g: Mean and fractile seismic hazard curves for 0.5 Hz at Dresden, 5% of critical damping (Reference 15)

AMPS(g) MEAN 0.05 0.16 0.50 0.84 0.95 0.0005 2.89E-02 1.32E-02 1.90E-02 2.76E-02 3.84E-02 4.77E-02 0.001 1.68E-02 7.23E-03 1.05E-02 1.60E-02 2.29E-02 2.96E-02 0.005 4.23E-03 1.16E-03 1.98E-03 3.84E-03 6.45E-03 8.60E-03 0.01 2.18E-03 3.33E-04 6.73E-04 1.79E-03 3.73E-03 5.35E-03 0.015 1.36E-03 1.36E-04 3.05E-04 9.65E-04 2.49E-03 3.90E-03 0.03 4.66E-04 2.25E-05 5.66E-05 2.29E-04 8.72E-04 1.72E-03 0.05 1.59E-04 4.98E-06 1.29E-05 5.83E-05 2.64E-04 6.64E-04 0.075 5.64E-05 1.40E-06 3.63E-06 1.72E-05 8.60E-05 2.42E-04 0.1 2.48E-05 5.42E-07 1.42E-06 6.73E-06 3.57E-05 1.07E-04 0.15 7.16E-06 1.34E-07 3.68E-07 1.74E-06 1.02E-05 3.09E-05 0.3 8.49E-07 1.01 E-08 3.33E-08 1.74E-07 1.21E-06 3.90E-06 0.5 2.12E-07 1.31 E-09 4.83E-09 3.23E-08 2.60E-07 1.08E-06 0.75 7.64E-08 2.76E-10 9.93E-10 8.12E-09 7.89E-08 4.07E-07

1. 3.71E-08 1.34E-10 3.42E-10 2.84E-09 3.33E-08 1.95E-07 1.5 1.29E-08 1.07E-10 1.29E-10 6.45E-10 8.98E-09 6.54E-08

3. 1.74E-09 8.12E-11 9.11E-11 1.18E-10 7.66E-10 7.45E-09

5. 3.28E-10 8.12E-11 9.11E-11 1.11 E-1 0 1.64E-10 1.23E-09 7.5 7.57E-11 8.12E-11 9.11E-11 1.11 E-10 1.11E-10 3.01E-10

10. 2.47E-11 8.12E-11 9.11E-11 1.11E-10 1.11E-10 1.49E-10 Dresden Generating Station Report No.: SL-012190, Revision 1 A-7 Correspondence No.: RS-14-067

Table A-2a: Amplification functions for Dresden (Reference 15) 100Hz Median Sigma Median Sigma Median Sigma Median Sigma 25Hz 10Hz 5Hz (PGA) AF ln(AF) AF ln(AF) AF ln(AF) AF ln(AF) 1.00E-02 1.22E+OO 6.93E-02 1.30E-02 1.12E+OO 7.06E-02 1.90E-02 1.27E+OO 1.48E-01 2.09E-02 1.32E+OO 1.14E-01 4.95E-02 1.09E+OO 8.88E-02 1.02E-01 9. 14E-01 1.41E-01 9.99E-02 1.26E+OO 1.66E-01 8.24E-02 1.32E+OO 1.17E-01 9.64E-02 1.02E+OO 9.23E-02 2.13E-01 8.63E-01 1.60E-01 1.85E-01 1.25E+OO 1.?OE-01 1.44E-01 1.31E+OO 1.18E-01 1.94E-01 9.63E-01 9.54E-02 4.43E-01 8.14E-01 1.72E-01 3.56E-01 1.23E+OO 1.74E-01 2.65E-01 1.30E+OO 1.19E-01 2.92E-01 9.29E-01 9.75E-02 6.76E-01 7.83E-01 1.78E-01 5.23E-01 1.22E+OO 1.77E-01 3.84E-01 1.29E+OO 1.21E-01 3.91E-01 9.06E-01 9.89E-02 9.09E-01 7.60E-01 1.83E-01 6.90E-01 1.20E+OO 1.79E-01 5.02E-01 1.29E+OO 1.23E-01 4.93E-01 8.87E-01 9.98E-02 1.15E+OO 7.39E-01 1.86E-01 8.61E-01 1.19E+OO 1.81E-01 6.22E-01 1.28E+OO 1.25E-01 7.41E-01 8.53E-01 1.01 E-01 1.73E+OO ?.OOE-01 1.91E-01 1.27E+OO 1.17E+OO 1.87E-01 9.13E-01 1.27E+OO 1.31E-01 1.01E+OO 8.26E-01 1.01E-01 2.36E+OO 6.69E-01 1.92E-01 1.72E+OO 1.14E+OO 1.92E-01 1.22E+OO 1.26E+OO 1.39E-01 1.28E+OO 8.05E-01 1.02E-01 3.01E+OO 6.45E-01 1.92E-01 2.17E+OO 1.11E+OO 1.96E-01 1.54E+OO 1.25E+OO 1.46E-01 1.55E+OO 7.88E-01 1.02E-01 3.63E+OO 6.26E-01 1.91E-01 2.61E+OO 1.08E+OO 1.98E-01 1.85E+OO 1.24E+OO 1.49E-01 Median Sigma Median Sigma Median Sigma 2.5 Hz 1Hz 0.5Hz AF ln(AF) AF ln(AF) AF ln(AF) 2.18E-02 1.07E+OO 1.14E-01 1.27E-02 1.50E+OO 1.43E-01 8.25E-03 1.37E+OO 1.43E-01 7.05E-02 1.06E+OO 1. 14E-01 3.43E-02 1.48E+OO 1.38E-01 1.96E-02 1.37E+OO 1.37E-01 1.18E-01 1.06E+OO 1.13E-01 5.51E-02 1.48E+OO 1.36E-01 3.02E-02 1.37E+OO 1.35E-01 2.12E-01 1.06E+OO 1.12E-01 9.63E-02 1.48E+OO 1.34E-01 5.11E-02 1.37E+OO 1.34E-01 3.04E-01 1.06E+OO 1.11E-01 1.36E-01 1.48E+OO 1.33E-01 7.10E-02 1.37E+OO 1.34E-01 3.94E-01 1.06E+OO 1.11E-01 1.75E-01 1.48E+OO 1.31E-01 9.06E-02 1.37E+OO 1.34E-01 4.86E-01 1.06E+OO 1.11E-01 2.14E-01 1.48E+OO 1.30E-01 1.10E-01 1.37E+OO 1.34E-01 7.09E-01 1.06E+OO 1.12E-01 3.10E-01 1.4BE+OO 1.29E-01 1.58E-01 1.37E+OO 1.34E-01 9.47E-01 1.06E+OO 1.15E-01 4.12E-01 1.4BE+OO 1.28E-01 2.09E-01 1.3BE+OO 1.34E-01 1.19E+OO 1.06E+OO 1.20E-01 5.1BE-01 1.48E+OO 1.27E-01 2.62E-01 1.3BE+OO 1.35E-01 1.43E+OO 1.06E+OO 1.24E-01 6.19E-01 1.4BE+OO , 1.27E-01 3.12E-01 1.3BE+OO 1.35E-01 Dresden Generating Station A-8 Report No.: SL-0121\lO, Revision 1 Correspondence No.: RS-14-007

Tables A-2b1 and A-2b2 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 10-4 and 1o-s 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, with 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.

Table A-2b1: Median AFs and sigmas for Model1, Profile 1, for 2 PGA levels (Reference 35)

M1P1K1 Rock PGA=0.194 M1P1K1 PGA=0.741 Freq. med. Freq. med.

Soil_SA sigma ln(AF) Soil_SA sigma ln(AF)

(Hz) AF (Hz) AF 100.0 0.196 1.008 0.088 100.0 0.591 0.799 0.099 87.1 0.197 0.989 0.089 87.1 0.594 0.776 0.099 75.9 0.199 0.955 0.089 75.9 0.598 0.738 0.100 66.1 0.202 0.889 0.090 66.1 0.604 0.668 0.101 57.5 0.208 0.784 0.092 57.5 0.614 0.564 0.104 50.1 0.219 0.688 0.102 50.1 0.634 0.477 0.111 43.7 0.236 0.627 0.118 43.7 0.662 0.421 0.118 38.0 0.252 0.608 0.126 38.0 0.701 0.412 0.124 33.1 0.269 0.613 0.135 33.1 0.747 0.421 0.140 28.8 0.296 0.673 0.149 28.8 0.806 0.462 0.169 25.1 0.337 0.761 0.192 25.1 0.887 0.511 0.197 21.9 0.403 0.953 0.220 21.9 1.016 0.625 0.249 19.1 0.456 1.094 0.158 19.1 1.157 0.733 0.246 16.6 0.485 1.210 0.171 16.6 1.275 0.851 0.193 14.5 0.498 1.299 0.207 14.5 1.369 0.969 0.200 12.6 0.505 1.354 0.212 12.6 1.451 1.067 0.219 11.0 0.494 1.359 0.191 11.0 1.512 1.152 0.208 9.5 0.460 1.322 0.163 9.5 1.479 1.190 0.190 8.3 0.436 1.358 0.155 8.3 1.391 1.225 0.175 7.2 0.436 1.449 0.147 7.2 1.373 1.302 0.185 6.3 0.410 1.450 0.130 6.3 1.372 1.394 0.168 5.5 0.374 1.386 0.133 5.5 1.274 1.366 0.160 4.8 0.338 1.279 0.159 4.8 1.140 1.257 0.177 4.2 0.309 1.207 0.144 4.2 1.026 1.174 0.171 3.6 0.293 1.173 0.110 3.6 0.978 1.157 0.123 3.2 0.262 1.115 0.122 3.2 0.891 1.125 0.102 2.8 0.229 1.025 0.120 2.8 0.787 1.052 0.118 2.4 0.208 1.012 0.118 2.4 0.712 1.037 0.119 2.1 0.196 1.048 0.124 2.1 0.660 1.061 0.119 1.8 0.202 1.205 0.154 1.8 0.667 1.205 0.143 1.6 0.201 1.386 0.133 1.6 0.663 1.389 0.132 1.4 0.199 1.594 0.136 1.4 0.652 1.596 0.130 1.2 0.198 1.803 0.105 1.2 0.649 1.814 0.101 1.0 0.176 1.774 0.095 1.0 0.579 1.803 0.087 Dresden Generating Station A-9 Report No.: SL-012190, Revision 1 Correspondence No.: RS-14-067

Table A-2b1: (Continued)

M1P1K1 Rock PGA=0.194 M1P1K1 PGA=0.741 Freq. med. Freq. med.

Soil_SA sigma ln(AF) Soil_SA sigma ln(AF)

(Hz) AF (Hz) AF 0.91 0.139 1.540 0.113 0.91 0.457 1.574 0.111 0.79 0.111 1.354 0.112 0.79 0.360 1.381 0.113 0.69 0.093 1.273 0.113 0.69 0.298 1.294 0.113 0.60 0.080 1.265 0.120 0.60 0.255 1.281 0.118 0.52 0.070 1.294 0.142 0.52 0.220 1.306 0.139 0.46 0.060 1.329 0.173 0.46 0.187 1.339 0.170 0.10 0.002 1.119 0.053 0.10 0.006 1.109 0.052 Table A-2b2: Median AFs and sigmas for Model 2, Profile 1, for 2 PGA levels (Reference 35)

M2P1K1 PGA=0.194 M2P1K1 PGA=0.741 Freq. me d. Freq. med.

Soii_SA sigma ln(AF) Soii_SA sigma ln(AF)

(Hz} AF (Hz} AF 100.0 0.216 1.113 0.086 100.0 0.788 1.064 0.088 87.1 0.218 1.094 0.086 87.1 0.796 1.040 0.088 75.9 0.221 1.060 0.086 75.9 0.808 0.998 0.088 66.1 0.225 0.993 0.085 66.1 0.831 0.919 0.087 57.5 0.235 0.887 0.082 57.5 0.877 0.805 0.084 50.1 0.254 0.796 0.092 50.1 0.963 0.725 0.099 43.7 0.279 0.741 0.125 43.7 1.076 0.685 0.139 38.0 0.297 0.717 0.140 38.0 1.145 0.673 0.155 33.1 0.317 0.723 0.119 33.1 1.220 0.688 0.131 28.8 0.352 0.801 0.115 28.8 1.351 0.774 0.127 25.1 0.411 0.926 0.159 25.1 1.569 0.905 0.171 21.9 0.495 1.171 0.170 21.9 1.884 1.159 0.178 19.1 0.559 1.340 0.149 19.1 2.111 1.336 0.150 16.6 0.568 1.416 0.212 16.6 2.119 1.416 0.213 14.5 0.562 1.467 0.227 14.5 2.073 1.467 0.229 12.6 0.558 1.495 0.224 12.6 2.033 1.495 0.226 11.0 0.527 1.449 0.190 11.0 1.903 1.449 0.191 9.5 0.484 1.393 0.147 9.5 1.729 1.392 0.149 8.3 0.462 1.439 0.138 8.3 1.633 1.438 0.138 7.2 0.458 1.524 0.121 7.2 1.608 1.523 0.122 6.3 0.423 1.498 0.135 6.3 1.474 1.498 0.135 5.5 0.385 1.425 0.129 5.5 1.329 1.425 0.130 4.8 0.346 1.308 0.152 4.8 1.187 1.309 0.152 4.2 0.317 1.237 0.142 4.2 1.081 1.237 0.142 3.6 0.297 1.192 0.110 3.6 1.008 1.192 0.110 3.2 0.264 1.125 0.132 3.2 0.891 1.125 0.132 2.8 0.229 1.027 0.123 2.8 0.768 1.028 0.123 2.4 0.209 1.013 0.122 2.4 0.696 1.014 0.121 2.1 0.197 1.051 0.128 2.1 0.653 1.051 0.128 Dresden Generating Station A-10 Report No.: Sl-012190, Revision 1 Correspondence No.: RS-14-067

Table A-2b2: (Continued)

M2P1K1 PGA=0.194 M2P1K1 PGA=0.741 Freq. med. Freq. med.

(Hz) Soil_SA sigma ln(AF) Soii_SA sigma ln(AF)

AF (Hz) AF 1.8 0.203 1.212 0.158 1.8 0.670 1.211 0.157 1.6 0.202 1.391 0.132 1.6 0.663 1.388 0.131 1.4 0.200 1.599 0.138 1.4 0.652 1.594 0.136 1.2 0.199 1.806 0.106 1.2 0.644 1.798 0.104 1.0 0.176 1.772 0.097 1.0 0.566 1.764 0.096 0.91 0.139 1.536 0.113 0.91 0.445 1.533 0.111 0.79 0.111 1.350 0.111 0.79 0.352 1.350 0.109 0.69 0.093 1.270 0.113 0.69 0.292 1.271 0.111 0.60 0.080 1.263 0.121 0.60 0.251 1.264 0.119 0.52 0.070 1.293 0.144 0.52 0.218 1.293 0.142 0.46 0.060 1.329 0.175 0.46 0.185 1.329 0.173 0.10 0.002 1.119 0.053 0.10 0.006 1.106 0.053 Dresden Generating Station A-11 Report No.: SL-012190, Revision 1 Correspondence No.: RS-14-067

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 11 0UTAGE 11 (Yes/No) {Yes/No)

1. Dresden Nuclear Power Station, Units 2 and As determined by Yes No 3, will perform a Risk Evaluation including a NRC prioritization High Frequency Confirmation evaluation. following submittal of all nuclear power plant Seismic Hazard Re-evaluations, but no later than December 31, 2019.

2. Dresden Nuclear Power Station, Units 2 and As determined by Yes No 3, will perform a Spent Fuel Pool evaluation NRC prioritization in accordance with EPRI Report 1025287, following submittal Section 7. of all nuclear power plant Seismic Hazard Re-evaluations, but no later than December 31 ,

2019.

3. Dresden Nuclear Power Station, Units 2 and December 31, Yes No 3, will prepare an Expedited Seismic 2014 Evaluation Process (ESEP} Report in accordance with EPRI Report 3002000704.

v t e Letter Sequence Response to RAI
TAC:MF5239, (Approved, Closed)
Initiation Request Acceptance... Administration Questions Answers 31 March 2014 26 December 2014 Results Approval Other: ML15173A213
MONTHYEAR2015-03-18 [Table View]

RS-14-067, 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) Re Recommendation 2.1 of The..

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