ML14177A086

06/26/2014 NRC Presentation Slides for Public Meeting with Southern on Seismic Reevaluation (GMRS)

ML14177A086
Person / Time
Site:	Hatch
Issue date:	06/26/2014
From:	Office of Nuclear Reactor Regulation
To:
Balazik M, NRR/JLD, 415-2856
References
Download: ML14177A086 (21)

Text

Near-term Task Force Recommendation21Seismic Recommendation 2.1 Seismic Hazard Evaluation Southern June 26, 2014 ReferencesforMeetingReferences for Meeting*Licensee Presentation Slides

-ML14176B239

• NRC Presentation Slides -ML14177A086

• Public Meeting Agenda -ML14169A437MtiFdbkF(tffb@)

• M ee ti ng F ee db ac k F orm (reques t from m fb@nrc.gov) *May 9, 2014, NRC letter regarding Seismic Screening and Prioritization Results for central and eastern US Licensees(ML14111A147)

• May 21, 2014, NRC memo providing preliminary staff groundmotionresponsespectraforcentralandground motion response spectra for central and eastern Licensees(ML14136A126)

• Meeting Summary to be issued within 30-day MeetingIntroductionMeeting Introduction Purpose: support information exchange and begin dialog to have ddifhfhidiffcommon un derstan ding o f t he causes o f t h e pr i mary differences between the preliminary NRC and licensee seismic hazard resultsBackground

NRCandlicenseeseismichazardrequireresolutionBackground

NRC and licensee seismic hazard require resolution to support a final seismic screening decision and to support related follow-on submittalsOutcomes:

• Begin NRC and licensee resolution to support regulatory decisionsanddevelopmentofseismicriskevaluations,as decisions and development of seismic risk evaluations, as appropriate

• Establish resolution path, including timelines and identification of potential information needs Look-ahead:

lPotentia l Next Steps

• NRCwillconsiderthemeetinginformationNRC will consider the meeting information

• Potential paths:Libitltliftibd-Li censee su b m it s supp l emen t a l i n f orma ti on b ase d on public meeting dialogNRCstaffissuesarequestforinformation

-NRC staff issues a request for information

-Licensee sends a revision or supplement to the seismichazardreport seismic hazard report*NRC completes screening review and issues thfilidtitiltt th e fi na l screen i ng d e t erm i na ti on l e tt er HatchUnitsNuclearPlantHatch Units Nuclear PlantSarah TabatabaiOfficeofResearchOffice of Research June 26, 2014

Screening*Screens in: Expedited Approach, Seismic Risk, High Frequency, SFP EvaluationsPiititiG2*P r i or iti za ti on G roup: 2 0.6 Licensee SSE (Unit 1)

Licensee SSE (Unit 2)0.4 0.5tion (g)()Licensee GMRSNRC GMRS (Updated) 02 0.3 ctral Accelera 0.1 0.2 Spe c 00.1110100Frequency (Hz)

StratigraphySite Geologic Column (Source: FSAR Figure 2.5-8, Rev. 19)

ControlPointControl Point NRC SS E Co ntr o l P o int El. 12 9 ft Submittal SS E Co ntr o l P o int El. 12 9 ftSSCooo9SSCooo9 VsProfileDevelopment VsProfile Development NRCTemplatevelocityprofilefor SubmittalISFSIdatausedtodevelopnearTemplate velocity profile for Vs=400 m/s (1312 ft/sec) from

SPID used for entire profile.

Template velocity profile supported ISFSI data used to develop near surface Vs profile (i.e. to a depth of 229 ft). Deeper portions of the profile (i.e. below a depth of 509 ft) by Vs data found in the literature were developed with nearby oil well exploration (Vp) data Epistemic Uncertainty in VsProfilesProfiles NRC A pp li ed a sca l e f ac t o r o f 1.2 t o th e Submittal A pp li ed a sca l e f ac t o r o f 1.5 7 t o th e ppedascaeacoooebase case profile for development of the upper and lower case profilesppedascaeacoo5oebase case profile for development

of the upper and lower case profiles Vs ProfilesShear-Wave Velocit y (ft/sec)0 500020004000600080001000012000y()0 5002000400060008000Shear-Wave Velocity (ft/sec)

NRC-BC NRC-LBC 1000 1500 t)50 100 150 NRC-UBC Licensee-BC Licensee-LBC Licensee-UBC 1500 2000 2500 o ntrol Point (f t 150 200 n trol Point (ft) 2500 3000 epth Below C o 250 300 pth Below Co n 3500 4000 D e NRC-BC NRC-LBC NRC-UBC 350 400 De p 4500 5000 NRC UBC Licensee-BC Licensee-LBC Licensee-UBC 450 500 00200040006000800010000Shear-Wave Velocity (ft/sec)Hawthorn Fm.

TFVs=2450 +/-200 ft/s in upper 50-100 ft(FSAR)Information from other sites:Saxena(2008) Vs=1500 -

1900 ft/s(HawthornFm

)500 1000 T ampa F m.Undifferentiated OligoceneOcala Fm. VogtleCOL: Vs=2650 ft/s Parker (2008) Vs=2296 ft/s (Ocala Fm.)1900 ft/s (Hawthorn Fm.)1500 n t (ft)Lisbon Fm. TallahataFm. Wilcox GroupClayton Fm.

at 149 ft (Lisbon Fm.

)Odumet al (2003): Vs=2805 ft/s at 98 ft (WilcoxGroup

)2000 2500 w Control Poi nPost Tuscaloosa Deposits (Wilcox Group)3000 3500 Depth Belo wTuscaloosa Fm.Odumet al (2003): Vs=2840 ft/s at 98 ft 3500 4000 NRC-BCUndifferentiated Early Cretaceous Deposits (Tuscaloosa Fm.

)4500 5000 NRC-LBC NRC-UBC Licensee-BCPre-Cretaceous Basement Rock 00200040006000800010000Shear-Wave Velocity (ft/sec) 500 1000An avera ge Poisson's ratio of 1500 nt (ft)Lisbon Fm.

g0.43 is reported for the Lisbon Formation at the Farley site 2000 2500w Control Poi NRC-BC NRC-LBC 3000 3500 Depth Belo NRC-UBCLicensee-BC (v=0.25)Licensee-BC (v=0.33) 4000Licensee-BC (v=0.45) 4500 5000 Aleatory Uncertainty in VsProfiles NRCSbittl NRC60 Randomizations Using USGS "B"SiteConditions S u b m itt a l30 Randomizations Using USGS "B""C"and"D"SiteConditionsfor "B" Site Conditions "B", "C", and "D" Site Conditions for the Upper-Range, Median, and Lower-Range Profiles, Respectively ln= 0.25 Upper 50 ft.ln= 0.15 Below 50 ft.ln= 0.25 Upper 90 ft.ln= 0.15 Below 90 ft.

Epistemic Uncertainty in Shear ModulusandDampingCurves Modulus and Damping Curves NRC M1 Submittal M1 M1EPRI Soil: 0 -276 ftEPRI Rock: 276 -500 ft Linear & No Dam p in g: > 500 ft M1Av. of EPRI 50-120 ft& 120-250 ft:

0 -129 ft Av. of EPRI 120-250 ft& 250-500 ft:

pg M2Peninsular: 0 -276 ftLinear&1%Damping:276 500 ft129 -279 ft Idriss& Boulanger Weathered Rock

Curves: 279 to 509 ftLinear&KappaBasedDamping:>

Linear & 1% Damping: 276 -500 ftLinear & No Damping: > 500 ft Linear & Kappa-Based Damping: > 500 ft Kappa and Epistemic Uncertainty NRCKappawascalculatedforeach SubmittalCalculatedakappadistribution 2 for Kappa was calculated for each base case profile using Q values from Campbell (2009). A ln=0.2 was applied to determine the range Calculated a kappa distribution 2 for each base case Vs profile based on

a median kappa of 0.04 sec (i.e. a deep soil site) and a ln=0.4 of kappasfor each base case profile.Base Case KappasLBC:0057 1 Kappa Distribution kL:0024 LBC: 0.057 BC: 0.040 UBC: 0.030 kL: 0.024 kM: 0.040 kU: 0.067 1Imposed an upper limit of 0.04 sec based on the SPID Guidance 2Clarification needed Am plification Functions p 5 6NRC (Input PGA = 0.01 g)NRC (Input PGA = 0.2 g)NRC (Input PGA = 0.5 g)Licensee (Input PGA = 0.01 g) 3 4 f icationLicensee (Input PGA = 0.2 g)Licensee (Input PGA = 0.5 g)NRC Sigma (Input PGA = 0.01 g)NRC Sigma (Input PGA = 0.2 g)NRC Sigma (Input PGA = 0.5 g)Licensee Sigma (Input PGA = 0.01 g) 2 3 Ampli fLicensee Sigma (Input PGA = 0.2 g)Licensee Sigma (Input PGA = 0.5 g) 0 10.1110100Frequency (Hz)

GMRS Comparison 1 0.1 t ion (g)e ctral Accelera t NRC GMRS 0.01 Sp e Licensee GMRSHatch Unit 2 SSEHatch Unit 1 SSE 0.0010.1110100Frequency (Hz)Licensee GMRS (NRC Calc.)

PrimaryDifferencesPrimary Differences

• Kappa-Southern considered Hatch to be a deep soil site and used a median kappa of 0.04 sec, while the NRC placed an upper limit of 0.04 sec on kappaClassificationasadeepsoilsiteinconsistentwithVs

-Classification as a deep soil site inconsistent with Vs base cases

• Largedifferencesinshear

-wavevelocitiesLarge differences in shearwave velocities below a depth of approximately 500 ftdue toanassumedPoisson

'sratio to an assumed Poissons ratio