ML112350873

Models and Methods Used for Casa Grande

ML112350873
Person / Time
Site:	South Texas
Issue date:	08/22/2011
From:	Letellier B, Sande T ALION Science & Technology Corp, Los Alamos National Laboratory
To:	Office of Nuclear Reactor Regulation
Singal, B K, NRR/DORL, 301-415-301
Shared Package
ML112350857	List: ML112350873 ML112350883
References
TAC ME5358, GSI-191, TAC ME5359
Download: ML112350873 (76)

Text

Risk-Informed GSI-191 South Texas Project Models and Methods Used for CASA Grande Bruce Letellier Los Alamos National Laboratory Los Alamos, NM Tim Sande Alion Science and Technology Albuquerque, NM Risk-Informed GSI-191 Resolution NRC Public Meeting Monday, August 22, 2011 Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 1

Risk-Informed GSI-191 Overview Required Inputs to CASA Grande Topical Approach and Implementation Plan

• Debris Generation

• Debris Transport

• Head Loss

• Air Intrusion

• Debris Bypass Interface With PRA Example Calculations to Illustrate Physics Models August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 2

Risk-Informed GSI-191 REQUIRED INPUTS TO CASA GRANDE August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 3

Risk-Informed GSI-191 Debris Generation Containment geometry Pipe break (LOCA) frequencies ZOI size/shape for plant materials Debris characteristics for plant materials Qualified coatings quantity for LOCA categories Unqualified coatings quantity Latent debris quantity Miscellaneous debris quantity August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 4

Risk-Informed GSI-191 Chemical Product Generation None required for initial quantification effort (initially assuming negligible impact for chemical effects)

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 5

Risk-Informed GSI-191 Debris Transport Blowdown transport fractions for LOCA categories Washdown transport fractions for LOCA categories Pool fill transport fractions for LOCA categories Recirculation transport fractions for LOCA categories Fiberglass erosion fractions for non-transporting pieces of debris No inputs required for upstream blockage in initial quantification August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 6

Risk-Informed GSI-191 Head Loss Strainer area/geometry Flow rate ECCS/CS pump NPSH margin August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 7

Risk-Informed GSI-191 Air Intrusion Vortexing

• Flow conditions (water level and flow rate) that would result in vortexing based on prototypical strainer testing (may not be an issue for PCI Sure-Flow design)

Gas desorption

• Containment pressure

• Containment pool temperature

• Strainer submergence depth August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 8

Risk-Informed GSI-191 Debris Bypass No additional input required for initial quantification effort.

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 9

Risk-Informed GSI-191 TOPICAL APPROACH AND IMPLEMENTATION PLAN August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 10

Risk-Informed GSI-191 Debris Generation Calculations CASA Grande will calculate debris quantities generated within given ZOIs for:

• Multiple break locations (welds on RCS pipes, wall rupture)

• Multiple break sizes at each location (2 to DEGB)

• Multiple jet orientations (if a non-spherical ZOI is used)

• Each type of insulation material in the vicinity of the break August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 11

Risk-Informed GSI-191 Input for Containment Geometry Import containment geometry from CAD model

• Concrete walls (robust barriers) imported using STL files

• Piping insulation imported through text files

• Weld locations imported through text files

• Equipment insulation recreated using primitive shapes August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 12

Risk-Informed GSI-191 CASA Grande Prototype August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 13

Risk-Informed GSI-191 Input for LOCA Frequencies Import LOCA frequency curves for each weld or other potential break location August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 14

Risk-Informed GSI-191 Normalized Freq Conditional Prob CASA Grande will only sample conditional probabilities Epistemic uncertainties on break frequency can be propagated if needed but no further epistemic factors will be segregated August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 15

Risk-Informed GSI-191 Input for ZOI Sizes and Shapes Define ZOI size and shape for each insulation material Spherical ZOI ANSI Jet ZOI Insulation Debris Insulation Debris Volume = 13.4 ft3 Volume = 10.2 ft3 August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 16

Risk-Informed GSI-191 Implementation Plan for ZOIs Plan for initial quantification effort:

• Use standard spherical and hemispherical ZOIs

• Use standard ZOI sizes (i.e. 17D ZOI for Nukon) scaled to appropriate break sizes Options for 2012 refinements:

• Modify ZOI shape using ANSI jet model, results of CFD modeling, etc.

• Modify ZOI size using PWROG blast testing, more realistic interpretation of AJIT data, CFD 17-D ZOI for 31 DEGB at STP encompasses approximately modeling, etc. half of Nukon insulation in SG compartments August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 17

Risk-Informed GSI-191 Input for Debris Characteristics Input appropriate debris characteristics:

• Insulation size distribution (fines, small pieces, large pieces, intact blankets)

• Coatings size distribution (particulate, chips)

• Latent debris distribution (fiber, particulate)

• Bulk and material densities for debris

• Characteristic size of fine material August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 18

Risk-Informed GSI-191 Implementation Plan for Characteristics Plan for initial quantification effort:

• Use NEI 04-07 baseline size distribution (fines and large)

• Assume all unqualified coatings fail as 10 micron particulate

• Use standard NEI 04-07 guidance for size and density Options for 2012 refinements:

• Alion refined size distribution (fines, small, large, and intact)

• Partial unqualified coatings failure Proprietary Alion debris size distribution methodology is used based on EPRI report to determine quantity of fines, small pieces, large pieces, and intact blankets based on distance of insulation from the break

• Unqualified epoxy fails as chips based on CPSES report August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 19

Risk-Informed GSI-191 Input for Unqualified Coatings Input unqualified coatings debris quantity:

• Total quantity of 3,366 lbm based on STP unqualified coatings logs

• Epoxy, IOZ, phenolic, alkyd, baked enamel Generic example of unqualified coatings debris following a DBA test August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 20

Risk-Informed GSI-191 Input for Qualified Coatings Input qualified coatings debris quantity for bounding LBLOCA:

• Total quantity of 586 lbm based on STP debris generation calculation

• Epoxy, IOZ, Polyamide Primer Options for 2012 refinements:

• Calculate bounding coatings quantities for various LOCA categories (i.e. large, medium, and small breaks)

Blast testing of qualified coatings system August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 21

Risk-Informed GSI-191 Input for Latent Debris Input latent debris quantity:

• Total quantity of 200 lbm based on STP debris generation calculation (latent debris survey showed 152 lbm)

• 85% dirt/dust, 15% fiber Generic example of latent debris collected from containment August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 22

Risk-Informed GSI-191 Input for Miscellaneous Debris Input miscellaneous debris quantity:

• Total assumed quantity of 100 ft2 based on assumption in STP debris generation calculation

• labels, tags, plastic signs, tie wraps Options for 2012 refinements:

• Evaluate transport potential for miscellaneous debris based on existing test data.

Generic examples of labels and tie wraps August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 23

Risk-Informed GSI-191 Chemical Product Generation Calculations If necessary, CASA Grande will automatically calculate chemical debris quantities generated based on:

• Quantity of fiberglass debris in containment pool

• Quantity of aluminum or other chemically reactive materials exposed to sprays or submerged in the pool

• Buffer type and time dependent pH in containment pool

• Time dependent temperature in containment pool

• Containment spray duration August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 24

Risk-Informed GSI-191 Input for Chemical Products

• Plan for initial quantification effort:

- Assume negligible impact from chemical effects for STP based on initial review of applicable ICET results

• Options for 2012 refinements:

SEM photo from ICET Test #2 (TSP with Fiberglass)

- Implement WCAP-16530 method if it is determined not to be overly conservative for STP

- Implement alternative method depending on approach used to account for chemical effects on the debris bed head loss Example of chemical goo produced using WCAP-16530 August 22, 2011, NRC PreLicensing Meeting recipe for STP test Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 25

Risk-Informed GSI-191 Debris Transport Calculations CASA Grande will use logic trees to calculate debris transport fractions with branches for:

• Blowdown transport

• Washdown transport

• Pool-fill transport

• Recirculation transport

• Erosion August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 26

Risk-Informed GSI-191 Implementation Plan for Blowdown Plan for initial quantification effort:

• Assume 100% of fine/small debris blown to pool

• Assume large pieces retained on grating based on STP debris transport calculation Options for 2012 refinements:

• Incorporate methods used in STP debris transport calculation for LOCA categories

• Refine blowdown calculations based on drywell debris transport study (DDTS) and other methods August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 27

Risk-Informed GSI-191 Implementation Plan for Washdown Plan for initial quantification effort:

• Assume 100% of fine/small debris washed to pool

• Assume large pieces retained on grating based on STP debris transport calculation Options for 2012 refinements:

• Incorporate methods used in STP debris transport calculation for LOCA categories

• Refine washdown calculations based on drywell debris transport study (DDTS) and other methods August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 28

Risk-Informed GSI-191 Implementation Plan for Pool-Fill Plan for initial quantification effort:

• Assume 100% of small debris remains in active pool

• Assume fine debris transports with flow (small amount transported to strainer and inactive regions)

Options for 2012 refinements:

• Perform CFD analysis to more accurately quantify pool-fill transport for small pieces of debris August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 29

Risk-Informed GSI-191 Implementation Plan for Recirculation Plan for initial quantification effort:

• Assume 100% transport of debris in active recirculation pool Options for 2012 refinements:

• Incorporate methods used in STP debris transport calculation for LOCA categories

• Perform additional CFD runs to address realistic flow conditions (water level and flow rate)

• Modify assumed debris distribution

• Modify conservative transport metrics

• Incorporate time dependence in the transport analysis August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 30

Risk-Informed GSI-191 Implementation Plan for Erosion Plan for initial quantification effort:

• Assume 1% spray erosion for small and large fiberglass debris held up on gratings above containment pool

• Erosion for non-transporting small fiberglass debris in pool is N/A since this debris is all assumed to transport Options for 2012 refinements:

• Apply proprietary Alion erosion test results for realistic recirculation pool erosion fraction Setup for Alion fiberglass erosion test with filter in flume suction pipe August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 31

Risk-Informed GSI-191 Implementation Plan for Upstream Blockage One of the four 30 inch vent holes in Plan for initial quantification STP secondary shield wall effort:

• Assume negligible based on STP debris transport calculation Options for 2012 refinements:

• Further evaluate potential for upstream blockage including blockage associated with a reactor nozzle break and any uncertainties associated with the current analysis One of the two 6 inch drains in STP refueling canal August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 32

Risk-Informed GSI-191 Head Loss Calculations CASA Grande will use a correlation to determine head loss over the range of relevant conditions:

• Strainer geometry

• Debris loads Fiber Particulate Microporous Chemical

• Flow rate

• Temperature

• NPSH margin August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 33

Risk-Informed GSI-191 Implementation Plan for Head Loss Correlation Plan for initial quantification effort:

• Use NUREG/CR-6224 correlation for fiberglass, particulate, and chips

• Assume microporous debris (minimal at STP) behaves similar to other particulate

• Assume chemical debris has negligible impact on head loss

• Assume uniform debris deposition and flow through strainer

• Calculate time dependent head loss Options for 2012 refinements:

• Perform tests to validate and/or refine head loss correlation for STP:

Perform tank testing to determine head loss reduction from non-uniform deposition on a complex geometry strainer, etc.

Perform vertical loop testing to determine head loss characteristics for Microtherm, WCAP-16530 chemical debris surrogate, etc.

Perform integrated chemical effects tests to more accurately quantify chemical effects Develop a bump-up factor or correlation to account for chemical debris August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 34

Risk-Informed GSI-191 NUREG/CR-6224 Correlation NUREG/CR-6224 correlation was developed based on flat plate vertical loop head loss testing with Nukon, iron oxide sludge, and paint chips:

m H = 3 . 5 S V2 1 .5 m (1 + 57 ) U + 0 . 66 S 3

m V (1 m )

U 2 Lm Where:

H = head loss (ft-water)

Sv = surface-to-volume ratio of the debris (ft2/ft3)

= dynamic viscosity of water (lbm/ft/sec)

U = fluid approach velocity (ft/sec)

= density of water (lbm/ft3) m = mixed debris bed solidity (one minus the porosity)

Lm = actual mixed debris bed thickness (in)

= 4.1528x10-5 (ft-water/in)/(lbm/ft2/sec2); conversion factor for English units August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 35

Risk-Informed GSI-191 Strainer Geometry Input strainer area and gap dimensions based on strainer drawings Calculate average approach velocity based on total strainer area Calculate interstitial volume based on gap dimensions Calculate increased approach velocity for large debris loads based on circumscribed strainer area August 22, 2011, NRC PreLicensing Meeting Photos and layout of STP PCI strainer Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 36

Risk-Informed GSI-191 Strainer Dimensions Strainer area (per train) =

1,818.5 ft2 Circumscribed area (per train) = 419.0 ft2 Interstitial Volume (per train)

= 81.8 ft3 Photos of STP PCI strainer August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 37

Risk-Informed GSI-191 Strainer Debris Loads Use debris generation and transport calculations for quantity and characteristics of debris on strainer for each postulated break at STP:

• Fiberglass

• Coatings particulate/chips

• Microtherm

• Dirt/dust

• Miscellaneous debris

• Chemical debris STP head loss test with fiber and particulate debris August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 38

Risk-Informed GSI-191 Flow Rate and Temperature Input total flow rate through each ECCS strainer for the specific case analyzed (maximum of 7,020 gpm per train at STP based on 1,620 gpm per HHSI pump, 2,800 gpm per LHSI pump, and 2,600 gpm per CS pump)

Calculate debris accumulation on each strainer based on relative flow split Input pool temperature to determine fluid density and viscosity August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 39

Risk-Informed GSI-191 NPSH Margin Input NPSH margin for each safety injection and containment spray pump Compare calculated debris bed head loss to the pump NPSH margin to determine whether the pump would fail NPSH Required

• LHSI Pumps = 16.5 ft

• HHSI Pumps = 16.1 ft

• CS Pumps = 16.4 ft NPSH Available (excluding clean strainer and debris losses)

• Start of Recirculation (267 F) = 22 ft

• 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (171 F) = 42 ft

• 30 days (128 F) = 51 ft August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 40

Risk-Informed GSI-191 Time Dependence A number of parameters used to determine ECCS strainer head loss are time dependent:

• Unqualified coatings failure

• Chemical product generation

• Debris transport and accumulation

• Total ECCS sump flow rate

• Pool temperature Due to changes in pool temperature, NPSH margin is also time dependent Some aspects of time dependence will be factored into CASA Grande to avoid over-conservatisms August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 41

Risk-Informed GSI-191 Air Intrusion Calculations CASA Grande will use test results and correlations to determine conditions that result in vortexing and gas desorption, along with the corresponding void fractions Froude numbers will be calculated to determine whether gas bubbles would accumulate or be drawn into sump suction piping Void fractions will be evaluated to determine:

• Potential for gas binding of ECCS pumps

• Effect of void fraction on NPSH

• Reduced efficiency of pumps, heat exchangers, etc. due to void fraction and resulting effects on system performance August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 42

Risk-Informed GSI-191 Vortexing Air intrusion due to vortexing is not an issue for STP since strainer design and configuration (under bounding water level and flow rate conditions) preclude vortex formation Generic strainer vortex test August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 43

Risk-Informed GSI-191 Gas Desorption Gas desorption void fractions will be calculated based on the strainer head loss, pool temperature, strainer submergence, and containment pressure based on Henrys Law CG = K G (T ) PG Where CG = Saturation concentration of air KG = Henrys constant for air at a given temperature T = Temperature PG = Partial pressure of air August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 44

Risk-Informed GSI-191 Debris Bypass Calculations CASA Grande will calculate debris bypass quantities based on test data and flow conditions The bypass debris quantities will be an output of CASA Grande used as an input for downstream effects calculations August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 45

Risk-Informed GSI-191 Implementation Plan for Bypass Plan for initial quantification effort:

• Use correlation of fiber bypass vs. flow rate developed by Gil Zigler :

BPtotal (g) = 1.538

• Q (gpm)

Options for 2012 refinements:

• Conduct bypass testing to evaluate bypass over the range of flow and debris load conditions for STP August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 46

Risk-Informed GSI-191 INTERFACE TO PRA August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 47

Risk-Informed GSI-191 CASA Interface to PRA Separate results will be compiled for each standard LOCA size (small, medium, large)

• Breaks below 2 diam will be assigned zero impact in the PRA

• All rupture opening sizes will be examined before binning

• Containment histories computed for conservative representatives of each size Conditional probabilities will be utilized to avoid confusion with PRA time-rate frequency assignments Alternative sump configurations will be assessed to match mechanical failure branches

• Later basis for possible operator mitigative action August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 48

Risk-Informed GSI-191 EXAMPLE CALCULATIONS TO ILLUSTRATE PHYSICS MODELS August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 49

Risk-Informed GSI-191 Break Frequencies for Cold Leg Welds Anywhere Each BF in Each BJ in Location in Plant Cold Leg Cold Leg Probability SLOCA at Specific Location 1 3.55E-05 6.56E-07 0.5 1.00E+00 3.55E-05 6.56E-07 0.8 3.10E-01 1.10E-05 2.03E-07 1.0 2.37E-01 8.40E-06 1.55E-07 1.5 1.65E-01 5.85E-06 1.08E-07 Cumulative 1.99 1.39E-01 4.95E-06 9.13E-08 Conditional 2.0 1.38E-01 4.91E-06 9.07E-08 Rupture 3.0 1.04E-01 3.69E-06 6.81E-08 Probability 4.0 8.17E-02 2.90E-06 5.36E-08 Given at 5.99 5.80E-02 2.06E-06 3.80E-08 Least a 0.5in. 6.0 5.80E-02 2.06E-06 3.80E-08 Break 6.8 5.07E-02 1.80E-06 3.33E-08 14.0 2.79E-02 9.91E-07 1.83E-08 20.0 1.71E-02 6.06E-07 1.12E-08 31.5 9.18E-03 3.26E-07 6.02E-09 44.5 5.40E-03 1.92E-07 3.54E-09 Based on total SLOCA Frequency of 2.04E-3 from NUREG/CR-6928 Excludes SGTR August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 50

Risk-Informed GSI-191 Example Break Case Cold leg break at BF weld next to RCP Break size equivalent to an 8 inch pipe break (i.e. an 8 inch hole in the side of the cold leg) 17D Spherical ZOI for Nukon*

28.6D Spherical ZOI for Microtherm*

• Since the break would result in a single sided jet (rather than two jets from a double ended guillotine break), the ZOI would be half the volume of the spherical ZOIs and could be modeled as a hemisphere per the NEI 04-07 guidance. To simplify the analysis, however, this example calculation conservatively uses the spherical ZOI.

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 51

Risk-Informed GSI-191 Nukon Debris Generation 17D ZOI x 8 inch diameter break = 11.3 ft radius sphere Quantity of Nukon = 141.0 ft3 Fines (7 m diameter) =

0.60

• 141.0 ft3 = 84.6 ft3 Large (>4 inch pieces) =

0.40

• 141.0 ft3 = 56.4 ft3 Density

• Bulk = 2.4 lbm/ft3

• Material = 175 lbm/ft3 August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 52

Risk-Informed GSI-191 Microtherm Debris Generation 28.6D ZOI x 8 inch diameter break = 19.1 ft radius sphere Volume = 1.2 ft3 = 18 lbm Bulk Density = 15 lbm/ft3 Mass = 1.2 ft3

• 15 lbm/ft3 = 18 lbm Fines = 1.00

• 18 lbm = 18 lbm Microtherm Distribution

• 3% fiber = 6 m diameter, 165 lbm/ft3

• 58% SiO2 = 20 m, 137 lbm/ft3

• 39% TiO2 = 2.5 m, 262 lbm/ft3 August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 53

Risk-Informed GSI-191 Coatings Debris Generation 586 lbm qualified coatings debris for bounding LBLOCA from STP debris generation calculation (based on 5D ZOI):

• 33 lbm epoxy = 10 m, 94 lbm/ft3

• 553 lbm IOZ= 10 m, 457 lbm/ft3 3,366 lbm unqualified coatings debris from STP debris generation calculation:

• 247 lbm alkyd = 10 m,97-195 lbm/ft3

• 843 lbm IOZ = 10 m,97-256 lbm/ft3

• 268 lbm baked enamel = 10 m,82-187 lbm/ft3

• 294 lbm epoxy dispersed through containment = chips*,75-118 lbm/ft3

• 1,714 lbm epoxy in reactor cavity = chips*, 130-140 lbm/ft3

• Epoxy chips will be assumed to be 10 m particulate for initial quantification August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 54

Risk-Informed GSI-191 Latent and Misc. Debris Generation 200 lbm latent debris from STP debris generation calculation:

• 170 lbm dirt/dust = 17.3 m, 169 lbm/ft3

• 12.5 ft3 fiber = 7 m diameter, 175 lbm/ft3 100 ft2 miscellaneous debris from STP debris generation calculation August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 55

Risk-Informed GSI-191 Blowdown and Washdown Transport 100% blowdown and/or washdown transport to pool at t = 0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> assumed for following debris:

• Nukon fines

• Microtherm

• Qualified coatings

• Latent debris Large pieces of Nukon retained on grating in SG compartments or upper containment; erosion fines assumed to reach the pool at t =

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Unqualified coatings in reactor cavity would not transport Other unqualified coatings assumed to fail and reach containment pool at t = 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Miscellaneous debris assumed to reach strainer at t = 0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 56

Risk-Informed GSI-191 Pool Fill Transport t ( Q / V pool )

x(t ) = xi e Where x(t) = Time dependent concentration of debris in pool xi = initial concentration of debris in pool t = time Q = Flow Rate Vpool = Pool Volume VCavity F fill up = 1 e VPool August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 57

Risk-Informed GSI-191 Pool Fill Transport, Cont.

Pool volume inside secondary shield wall at 18 inch depth = 5,046 ft3 Cavity volume for each sump = 240 ft3 Inactive cavity volume (containment sump and elevator pit) = 749 ft3 3240 ft 3 + 749 ft 3 F fill up ( ECCS Sump Cavity ) = 1 e 5, 046 ft 3

= 0.25 Split proportional to volumes:

• 8% to two active sumps

• 4% to inactive sump

• 13% to inactive cavities August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 58

Risk-Informed GSI-191 Erosion of Large Pieces of Nukon An erosion fraction of 1% was used for large pieces of Nukon retained in upper containment: 56.4 ft3

• 0.01 = 0.6 ft3 August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 59

Risk-Informed GSI-191 Time Dependent Recirculation Transport t ( Q / V pool )

x(t ) = xi e Total sump flow rate for two train operation = 14,040 gpm Total pool volume corresponding to 3.19 ft minimum LBLOCA water level: 46,955 ft3 Initial concentration of debris at the beginning of recirculation (t = 24 minutes) includes 75% of the Nukon, Min-K, qualified coatings, and latent debris fines. At t = 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, the concentration will be increased to include 100% of the unqualified coatings and Nukon erosion fines.

Pool turnover time = 25 minutes August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 60

Risk-Informed GSI-191 Time Dependent Recirculation Transport, Cont.

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 61

Risk-Informed GSI-191 Time Dependent Recirculation Transport, Cont.

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 62

Risk-Informed GSI-191 Nukon Debris Transport (Fines)

Blowdown to pool: 100%

Washdown to pool: 100%

Pool fill:

• 4% to each strainer

• 13% to inactive regions Recirculation to strainers:

• 0% to inactive strainer

• 50% to each active strainer Erosion: N/A Overall Transport: 83%

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 63

Risk-Informed GSI-191 Nukon Debris Transport (Large)

Blowdown to pool: 0%

Washdown to pool: 0%

Pool fill: N/A Recirculation to strainers:

N/A Erosion:

• Spray: 1%

• Pool: N/A Overall Transport: 1%

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 64

Risk-Informed GSI-191 Microtherm Debris Transport (Fines)

Blowdown to pool: 100%

Washdown to pool: 100%

Pool fill:

• 4% to each strainer

• 13% to inactive regions Recirculation to strainers:

• 0% to inactive strainer

• 50% to each active strainer Erosion: N/A Overall Transport: 83%

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 65

Risk-Informed GSI-191 Qualified Coatings Debris Transport (Fines)

Blowdown to pool: 100%

Washdown to pool: 100%

Pool fill:

• 4% to each strainer

• 13% to inactive regions Recirculation to strainers:

• 0% to inactive strainer

• 50% to each active strainer Erosion: N/A Overall Transport: 83%

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 66

Risk-Informed GSI-191 Unqualified Coatings Debris Transport (Fines)

Blowdown to pool: N/A Washdown to pool: 100%

Pool fill: N/A Recirculation to strainers:

• 0% to inactive strainer

• 50% to each active strainer Erosion: N/A Overall Transport: 100%

Transport for Unqualified Coatings in Reactor Cavity:

0%

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 67

Risk-Informed GSI-191 Latent Debris Transport (Fines)

Blowdown to pool: N/A Washdown to pool: 100%

Pool fill:

• 4% to each strainer

• 13% to inactive regions Recirculation to strainers:

• 0% to inactive strainer

• 50% to each active strainer Erosion: N/A Overall Transport: 83%

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 68

Risk-Informed GSI-191 Time Dependent Transport Quantities Debris t = 24 min t = 3 hr t = 24 hr t = 27 hr Nukon Fines 6.8 ft3 70.2 ft3 70.2 ft3 70.2 ft3 Nukon Large 0.0 ft3 0.0 ft3 0.0 ft3 0.6 ft3 Microtherm 1.4 lbm 14.9 lbm 14.9 lbm 14.9 lbm Qualified Epoxy 3 lbm 27 lbm 27 lbm 27 lbm Qualified IOZ 44 lbm 459 lbm 459 lbm 459 lbm Unqualified Alkyd 0.0 lbm 0.0 lbm 0.0 lbm 247 lbm Unqualified Epoxy 0.0 lbm 0.0 lbm 0.0 lbm 294 lbm Unqualified IOZ 0.0 lbm 0.0 lbm 0.0 lbm 843 lbm Unqualified Baked Enamel 0.0 lbm 0.0 lbm 0.0 lbm 268lbm Latent Dirt/Dust 14 lbm 141 lbm 141 lbm 141 lbm Latent Fiber 1.0 ft3 10.4 ft3 10.4 ft3 10.4 ft3 Miscellaneous Debris 100 ft2 100 ft2 100 ft2 100 ft2 August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 69

Risk-Informed GSI-191 Head Loss Calculations Basic assumptions for example calculation:

• Homogeneous and contiguous bed at every composition and all times

• No chemical product formation

• Particulate limited bed compression

• Equal debris to each of the two operating trains

• Debris transported during pool fill-up placed uniformly on strainer despite later submergence history August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 70

Risk-Informed GSI-191 Geometric Loading Table Clean strainer area of 1818.5 ft2 Circumscribed area of 419 ft2 Circumscribed debris load of 0.5 in and 82 ft3 Fiber loading shown as blue dots August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 71

Risk-Informed GSI-191 Bed-Inventory History August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 72

Risk-Informed GSI-191 Particle-to-Fiber Mass Ratio ()

August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 73

Risk-Informed GSI-191 Head Loss Summary Time Temp LHSI NPSHA NPSH Strainer (hr) (F) NPSHR (ft) Margin HL (ft)

(ft) (ft) 0.4 267 16.5 22.1 5.6 0.0 3 246 16.5 22.0 5.5 0.2 24 171 16.5 41.9 25.4 0.4 27 169 16.5 42.0 25.5 3.3 720 128 16.5 50.9 34.4 4.4 August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 74

Risk-Informed GSI-191 Gas Desorption Calculations The gas void fraction can be calculated using the flow rate (7,020 gpm), time dependent temperature and head loss, and the following assumptions:

• Saturated equilibrium conditions in the containment pool

• 100% relative humidity in containment

• Containment pressure of 14.7 psia when temperature is less than 212F

• Average strainer submergence of 22 inches Time Temp Strainer Air Void (hr) (F) HL (ft) Released Fraction (ft3/hr) (%)

24 171 0.4 0 0.00 27 169 3.3 66 0.12 720 128 4.4 87 0.15 August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 75

Risk-Informed GSI-191 Debris Bypass Calculations Fiber bypass fraction is calculated using the correlation:

BPtotal (g) = 1.538

• Q (gpm)

Total sump flow rate for two train operation is 14,040 gpm with 8,840 gpm through the SI pumps and 5,200 gpm through the CS pumps STP reactor vessel: 193 fuel assemblies BPtotal = 1.538

• 14,040 gpm = 21,600 g (47.6 lbm; 19.8 ft3)

• Split to SI pumps: 21,600 g * (8,840 /14,040) = 13,600 g

• Split to CS pumps: 21,600 g * (5,200 / 14,040) = 8,000 g Incore fiberglass debris load: 70.5 g / fuel assembly August 22, 2011, NRC PreLicensing Meeting Operated by Los Alamos National Security, LLC for the U.S. Department of Energys NNSA Slide 76