ML14176B239

06/26/2014, Southern Nuclear Operating Company Seismic Reevaluation - GMRS NTTF 2.1 Presentation Slides

ML14176B239
Person / Time
Site:	Hatch
Issue date:	06/26/2014
From:	Southern Nuclear Operating Co
To:	Office of Nuclear Reactor Regulation
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Download: ML14176B239 (49)

Text

Southern Nuclear Operating p g Companyp y Seismic Reevaluation GMRS - NTTF 2.1 U.S. Nuclear Regulatory Commission Meeting June 26, 2014

Southern Nuclear Team Charles Pierce Regulatory Affairs Director John Giddens Licensing Manager - Fukushima

Response

Don Moore Consulting Engineer - Seismic Melanie Brown

• Principal Engineer - Seismic Farhang Ostadan Chief Geotechnical Engineer/Bechtel Tarek Elkhoraibi Senior Geotechnical Engineer/Bechtel John Damm Senior Geotechnical Engineer/Bechtel g

Mike Lewis

• Corporate Geotechnical Manager/Bechtel 2

Purpose and Scope of Meeting To present the basis for the March Purpose:

2014 GMRS submittals and understand the differences with NRC preliminary GMRS S

Scope: Edwin I. Hatch Nuclear Plant

• Previous Site Characterization

• Basis for soil profile for the GMRS

• Methodology for developing the GMRS Joseph M. Farley Nuclear Plant

• Low Frequency Evaluations Conclusions & Use of the GMRS 3

Edwin I. Hatch Nuclear Plant Units 1 & 2 4

5 6

P Previous i Site Sit Characterization Ch t i ti D M Don Moore 7

FSAR Soil Dynamic y Properties p

• Single Shear Wave Velocity (Vs) =

2450 fps

• Based on late 1960s seismic refraction survey

• No use of site boring data

• SSI analyses used Vs of 2450 fps for the elastic half-space (soil springs) 8

1980s Hatch Pilot Seismic Margin A

Assessment t

• Reassessed site profile to obtain Vs vs. Depth using SPT data & soil type

• Performed new SSI analysis

• Performed EPRI Seismic Margin Assessment (SMA) soil failure analysis 9

10 11 Evaluation of Liquefaction Potential

• HCLPF for soil liquefaction was 0.28g

• Potential for liquefaction exists in only limited soil layer at significant depth below grade 12

Site Characterization

• Vs profile: Softer soil properties as compared to original FSAR

• Vs profile: Soil site where Vs varies with depth

• Vs profile: Caused a shift of the peak SA of the ISRS to a lower frequency range

• Vs profile: Soil liquefaction HCLPF ~= 0 0.3g 3g 13

Closure of Soils Issues

• NRCs Seismic Design Margins Working Group

• Dan D Guzy, G G Bagchi, G. B hi J.

J Chen, Ch P P. YY. Ch Chen, N N.

Chokshi & L. Phillips

• NRC Resolution & Closure of all soils issues NRC letter dated 4/29/1990 allll off th the studies t di h have bbeen performed f d iin accordance with the guidelines for seismic margins a g s assessassessment e taand d in a manner a e coconsistent s ste t with the best of the state-of-the art practicehaveresolved all previous concerns 14

Hatch Seismic Issues Resolved

• NRC Letter from K. N. Jabbour ((NRC Project j

Manager) to Southern Nuclear dated April 16, 1991, Seismic Design Issues -HatchUnits 1 and 2.

The NRC staff has reviewed your submittal The (Hatch SMA report) and finds that the concerns identified previouslyhave been satisfactorily resolved 15

NRC References

• Letter from Dan Guzy (NRC, Seismic Design Margins Working Group),

Resolution and Closure of All Soils Issues in the Hatch Review, dated April p 29,, 1990.

• Memorandum from Dan Guzy and Goutam Bagchi (NRC, Seismic Design Margins Working Group), Final Evaluation of the Hatch Margins Review, dated May y 2. 1990

• Letter from D. R. Davis (Hatch Seismic Margin Assessment Peer Review Group) to Dan Guzy (NRC Seismic Design Margins Working Group), with enclosed report, p , Hatch SMA Peer Review Group p Final Report:

p Evaluation of the Application of the NRC and EPRI Seismic Margins Methodologies, dated May 3, 1990.

• Letter from K. N. Jabbour ((NRC,, Project j Manager),

g ), Seismic Design g Issues

- Edwin I. Hatch Nuclear Plant, Units 1 and 2), dated April 16, 1991.

• Letter from Dr. Michael P. Bohn ((Sandia National Laboratories)) to Dr.

Nilesh Chokshi (NRC) with enclosed report, Independent Evaluation of the Hatch Seismic Margin Assessment Seismic Building Response and Floor Spectra, dated July 5, 1991. 16

Basis for Soil Profile for the GMRS J h D John Damm 17

Dynamic Soil Properties R i it d for Revisited f Development D l t off GMRS

• Project j setting g and data sources

- On-site data and nearby wells

• Site stratigraphy

- Depth to hard rock

• Shear wave velocity profile

- Base case and uncertainties

• Strain-dependent soil properties

- Published relationships and uncertainties 18

Geologic Setting

• Atlantic Coastal Plain physiographic province

• 80 mi SSE of the Fall Line

• FSAR Figure 2.5-5

• Geologygy typically yp y consists of alternating strata of very gently dipping sedimentary dipping, deposits p to base of Coastal

• Depth Plain sediments reported at 4,100 ft in the vicinity 19 of Plant Hatch

Geologic Setting Plant Hatch HNP FSAR - Figure 2.5-5 20

Data Sources

• Hatch FSAR

- Borehole data (1967)

- Maximum depth of 150 ft

- Alternating layers of sands, cemented sands, and stiff to hard clays

• Georgia DNR DNR, 1981

- Sonic data in nearby, deep exploratory borehole

- Total depth, 11,470 ft

• Seismic Margin Assessment Assessment, 1991

- Vs correlated from on site SPT data

• Independent Spent Fuel Storage Installation, 1998

- Seismic S i i crossholeh l survey, on site it

• Independent Spent Fuel Storage Installation, 2011

- PS logging survey, on site 21

Nearby Exploratory Well Plant a Hatch ac AP Snipes No.1 22

Nearby Exploratory Well Source: Petroleum Exploration Wells in Georgia, 1979-1984, William M. Steele, Georgia Department of Natural Resources, Environmental Protection Division, Georgia Geologic Survey 23

Seismic Margin Assessment, 1991

• Dr. Idriss (Woodward-Clyde Consultants)

• SPT blow bl countt data d t from f 54 FSAR bboreholes h l

• Vs developed from correlation with SPT N values, Sykora and Stokoe (1983)

• Published relationships for modulus reduction and damping based on material type

• Best estimate Vs profile with upper and lower bound 24

Independent Spent Fuel Storage Installation (ISFSI),

(ISFSI) 1998

• The ISFSI is adjacent to the Site Protected Area

• Dr. I. M. Idriss

• Crosshole and downhole seismic surveys to depth of 150 ft

• Cone penetrometer testing

• Published relationships for modulus reduction and damping g based on material type y

25

Independent Spent Fuel Storage Installation (ISFSI),

(ISFSI) 2011

• Subsurface investigation included standard penetration testing, undisturbed sampling, and laboratory testing

• Maximum depth 150 ft.

• Index testing of representative samples

• Piezometers for groundwater level measurements

• Downhole geophysical logging including P-S methods th d tto measure velocity l it 26

Data Contributions to the Vs Profile

• Near surface materials (plant grade at El. 129 ft to El. -100 ft)

- SPT data, soil type and laboratory test results from FSAR boreholes, 1967

- Crosshole velocity data from ISFSI study study, 1998

- SPT data, soil type, laboratory test results, and PS logging velocity data from ISFSI study, 2011

• Deep materials (below El. -100 ft)

- Material descriptions p and strata thicknesses from nearby (5 mi) oil test well reported in FSAR

- Gamma ray and sonic (Vp) log data from nearby (27 mi) oil exploration well 27

Using Velocity Data at Deeper Depths

• The measured P-Wave Velocity shows increasing velocity trend with depth

• For sedimentary deposits, one must account for the effects of confining pressure on velocity when comparing similar materials

• Poisson Poissonss Ratio

- Reasonable Poissons Ratio for sandy material was assumed to obtain the Vs.

• Epistemic uncertainty accounts for uncertainties of Vs 28

Stratigraphy

• Stratigraphy developed in FSAR from nearby y (5

( mi)) deep p exploratory well

• Formations consist of alternating layers y of sand,, clay,y, and fossiliferous limestone

• Unit wt. of 125 pcf and Poissons ratio of 0.25 ((except p 0.33 -

Hawthorne)

• Hard rock (9,200 fps) at ~ El.

4,000

, ft,, unit wt. of 165 pcf p

• Depth to Hard rock confirmed on sonic log in nearby (27 mi) well 29

Capturing Epistemic Uncertainty i the in th Velocity V l it Profiles P fil 30

Shear Wave Velocity Profiles

((3 base case profiles) p ) to El -300 ft Shear Wave Velocity (fps) 0 1000 2000 3000 4000 5000 6000 150 Insitu Stratigraphy/Geology 100 50 Hawthorne Median 0

Lower range Elevattion (ft)

-50 (10th %)

Upper range

-100 (90th %)

-150 Tampa

-200

-250

-300 31

Shear Wave Velocity Profiles

((3 base case profiles) p ) to Hard Rock Shear Wave Velocity (fps) 0 2000 4000 6000 8000 10000 12000 14000 16000 500 Insitu Stratigraphy/Geology 0 Hawthorne Tampa Oligocene

-500 Ocala

-1000 Lisbon Tallahatta Median

-1500 Wilcox Clayton Elevattion (ft)

-2000 Lower range (10th %)

Post Tuscaloosa

-2500 Upper range (90th %)

-3000 Tuscaloosa

-3500 Comanchean

-4000 Triassic

-4500

-5000 32

Nonlinear Dynamic Material Properties

• No site specific modulus degradation and damping data available

• Grade to El. -150: to capture epistemic uncertainty, 2 sets of EPRI 1993 sand curves ((SPID B-3.2.1))

are used in soil amplification analysis and the result are equally weighted

• El. -150 to El. -380: Used Idriss and Boulanger curves for weathered rock based on Vs values

• El.

El -380 380 to top of hard rock (Triassic)

(Triassic): linear material, calculate damping from kappa 33

Nonlinear Dynamic Material Properties Section of Vs Profile Recommended G/Gmax and Damping Relationships G

Ground d surface f to t El.

El 0 2 sets:

t EPRI curves 50-120 50 120 and d 120-250 120 250 equally ll weighted i ht d El. 0 to El. -150 2 sets: EPRI curves 120-250 and 250-500 equally weighted El. -150 to El. -380 Idriss & Boulanger curves for weathered rock El -380 El. 380 to El El. -3,958 3 958 (Triassic) linear material, material compute damping from kappa Below -3,958 Halfspace, constant damping ratio of 1 percent 34

Summary of Dynamic Soil Properties

• Hatch profile consists of Coastal Plain sediments to a depth of 44,100 100 ft

• Alternating strata of clay, sand, limestone, marl, and partially indurated sediments

• Below a depth of 500 ft, Vs increases to above 4,000 fps

• Non linear behavior of upper 280 ft of sediments characterized with sand curves

• Non linear behavior of sediments from 280280 to 500 ft depth characterized with weathered rock curves

• Below 500 ft to top of hard rock, shear modulus is linear and damping calculated using kappa 35 estimate

Methodology gy for Developing p g the GMRS T k Elkhoraibi Tarek Elkh ibi 36

Kappa 37

Kappa 38

Site Amplification Analysis 60 randomized profiles fil per soilil column case Each subjected to HF and LF rock motions at MAPE 1E-3 through 1E-7 Total of 10,800 Total = 1.0 runs ((18 x 60 x 2 x 5) 39

Profile Simulation (Randomization)

Randomized parameters for aleatory variability

• Shear-wave velocity

• Soil layer thicknesses

• Depth to bedrock

• Strain-independent damping for soil layers below 509 ft 40

Profile Simulation (Randomization)

Hatch-VsM-G1-kM Insitu 1 - EPRI 50-120 Randomized 1 1 0.9 0.9 0.8 0.7 0.8 0.7 parameters for aleatory p y 0.6 0.6 variability Log-SD G/Go 0.5 0.5 0.4 0.4 0.3 0.2 Simulated Median 0.3 0.2

• Strain-dependent shear modulus for Input BE Min and Max Bounds 0.1 0.1 Simulated SD Input SD top 509 ft 0 -4 -3 -2 -1 0 01 10 10 10 10 10 10 Strain [%]

20 1 Simulated Median Input BE 18 0.9 Min and Max Bounds

• Strain-dependent Simulated SD 16 Input SD 0.8 14 0.7 12 0.6 damping p g for top p 509 Damping [%]

Log-SD ft 10 0.5 8 0.4 6 0.3 4 0.2 2 0.1 0 -4 -3 -2 -1 0 01 10 10 10 10 10 10 Strain [%]

41

Input Rock Motions HF3 LF3 10 HF4 LF4 HF5 LF5 HF6 LF6 HF7 LF7 5% Dam mped Spectral A Accel. [g]

1 0.1 0.01 0.001 0.1 1.0 10.0 100.0 Frequency [Hz]

42

Amplification Functions 30 3.0 HF 1E-4 LF 1E-4 5% Damped, Weig ghted Average e Site Amplific cation HF 1E-5 2.5 LF 1E-5 2.0 1.5 1.0 05 0.5 0.0 01 0.1 10 1.0 10 0 10.0 100 0 100.0 Frequency [Hz]

43

GMRS Using Approach 3 in NUREG/CR-6728 0.7 UHRS 1E-5 0.6 GMRS UHRS 1E-4 5% Damping Spectral Acceleration [g]

0.5 0.4 0.3 0.2 0.1 0.0 0.1 1 10 100 Frequency [Hz]

44

How the SPID was Implemented 45

Joseph M. Farley Nuclear Plant Units 1 & 2 46

47 Low Frequency Evaluation

• Screens in under the special screening considerations for a low seismic hazard site

• FNP not required to provide Expedited Seismic Evaluation Process

• Section 3.2.1.1 of the SPID provides guidance for performing low frequency evaluations 48

Conclusions & Use of the GMRS

• Hatch Site

- Multiple p sources used to develop p soil p profile

- Guidance in SPID Appendix B was used

- Judgments made to implement the Guidance in SPID A

Appendix di B were appropriate i

- SNC is using the Hatch GMRS submitted in March to comply with ESEP

- SNC is using the Hatch site seismic hazard submitted in March to benchmark ongoing Hatch SPRA development

• Farley Site

- SNC is using the Farley GMRS submitted in March complete l t the th Low L F Frequency EEvaluations.

l ti 49