ML113050632

Licensee Handouts from November 1, 2011 Meeting with STP Nuclear Operating Company on GSI-191

ML113050632
Person / Time
Site:	South Texas
Issue date:	10/26/2011
From:	Howe K, Leavitt J, Sande T, Zigler G ALION Science & Technology Corp, Univ of New Mexico
To:	Balwant Singal Plant Licensing Branch IV
Singal, B K, NRR/DORL, 301-415-301
Shared Package
ML113050615	List: ML113050623 ML113050632
References
TAC ME5358, GSI-191, TAC ME5359
Download: ML113050632 (27)

Text

Risk Informing STP GSI-191 Chemical Effects Risk Informed GSI-191 Resolution Tuesday, November 1 Public Meeting with STP Nuclear Operating Company Timothy D. Sande Dr. Kerry J. Howe Gilbert L. Zigler Janet J. Leavitt 11/1/11 Pre-Licensing Meeting 1

Risk Informed GSI-191 Outline

• Meeting Objective

• Purpose of Chemical Effects Program

• Significant/Insignificant Contributors

• STP Parameters

• Previous Tests Relevant to STP

• Preliminary Ideas for Testing

• Preliminary Ideas for Risk Informed Application

• Conclusions 11/1/11 Pre-Licensing Meeting 2

Risk Informed GSI-191 Meeting Objective

• Present the STP risk informed chemical effects approach to the NRC

• Obtain NRC comments prior to developing an initial test plan 11/1/11 Pre-Licensing Meeting 3

Risk Informed GSI-191 Goals of Risk Informed Chemical Effects Program

• Fully understand physical and chemical phenomenon related to chemical effects at STP through research, testing, and modeling y

• Develop an analytical model for chemical precipitate formation that can be implemented in CASA Grande

• Develop an algorithm for chemical effects head loss that can be implemented in CASA Grande

• Validate models with prototypical testing 11/1/11 Pre-Licensing Meeting 4

Risk Informed GSI-191 Significant Contributors

• Time

• Concrete Area

• Buffer

• Corrosion

• pH

• Dissolution

• Temperature

• Inhibition

• Pool Volume

• Solubility Limits

• Insulation Types

• Kinetics

• Insulation Quantities

• Precipitate Types

• Aluminum Area

• Precipitate Properties 11/1/11 Pre-Licensing Meeting 5

Risk Informed GSI-191 Significant Contributors

• Copper Area

• HX Temperature Drop

• Lead Area

• Retrograde Solubility

• Zinc Coatings

• Acid Formation

• Concrete Aging

• RCS Chemistry

• RWST Chemistry 11/1/11 Pre-Licensing Meeting 6

Risk Informed GSI-191 Insignificant Contributors

• Carbon Steel

• Galvanized Steel

• Nickel

• Organic Material

• RCS Crud

• Radiolysis Products

• Biological Effects 11/1/11 Pre-Licensing Meeting 7

Risk Informed GSI-191 STP Parameters

• Buffer: TSP

• Nominal pH: ~7.6

• LBLOCA Containment Temperature: 260°F max to 120 120°FF at 30 days

• LBLOCA Pool Temperature: 267°F max to 126°F at 30 days

• Pool Volume: 31,431 ft3 min, 89,350 ft3 max

• Nominal Spray Duration: 12 hr 11/1/11 Pre-Licensing Meeting 8

Risk Informed GSI-191 STP Parameters

• RCS Chemistry: 1,400 - 0 ppm boron, 3.5 - 0.4 ppm lithium, 1 - <0.1 ppm Silica

• RWST Chemistry: 2,850 - 2,975 ppm boron, 1 -

6 ppm Silica

• Pool Chemistry: 2,372 - 2,878 ppm boron

• Insulation: Nukon, Microtherm (penetrations), SS RMI (reactor cavity)

• Coatings: Epoxy, IOZ, Polymide, Alkyd, Enamel

• Nominal Aluminum Area: 5,567 ft2 11/1/11 Pre-Licensing Meeting 9

Risk Informed GSI-191 STP Time Dependent pH 11/1/11 Pre-Licensing Meeting 10

Risk Informed GSI-191 STP Time Dependent Temperature 150°F 150 F at 3.5 3 5 days 140°F at 7 days 11/1/11 Pre-Licensing Meeting 11

Risk Informed GSI-191 Previous Tests Relevant to STP

• WCAP-16530 (single effects)

• WCAP-16785 (partially integrated effects)

• ICET Test 2 (integrated effects)

• Alion Vogtle Vuez Tests (integrated effects with head loss)

• Alion Vogtle and Calvert Cliffs High Temperature Vertical Loop (HTVL) Tests (aluminum solubility) 11/1/11 Pre-Licensing Meeting 12

Risk Informed GSI-191 STP WCAP-16530 Prediction Material Released Quantity (kg)

Calcium* 63.06 Silicon 208.85 Aluminum 82.92 Precipitate Quantity (kg)

Sodium Aluminum Silicate 649.5 Aluminum Oxyhydroxide 35.7 Calcium Phosphate* 162.7

• Includes marinite source that is no longer in containment 11/1/11 Pre-Licensing Meeting 13

Risk Informed GSI-191 STP WCAP-16785 Prediction Refinement Aluminum NaAlSi3O8 AlOOH Ca3(PO4)2 (ppm) (kg) (kg) (kg)

Base Case 82.9 649.5 35.7 162.7 Silicon Inhibition 18.3 177.4 0.0 162.7 Phosphate Inhibition 69.4 649.5 5.6 162.7 Solubility Limits 82.9 0.0 0.0 162.7 11/1/11 Pre-Licensing Meeting 14

Risk Informed GSI-191 ICET Test Overview Insulation (%) Chemical byproducts ICET Test Controlling pH Measured pH Visible at test Visible upon Number buffer system Fiberglass Cal-Sil temperature cooling 1 Borate (NaOH) 100 0 9.3 - 9.5 No Yes 2 Phosphate (TSP) 100 0 7.1 - 7.4 No No Yes, only 3 Phosphate (TSP) 20 80 7.3 - 8.1 during first few No hours 4 Borate (NaOH) 20 80 9.5 - 9.9 No No 5 Borate (Borax) 100 0 8.2 - 8.5 No Yes Test Duration: 30 days Test Temperature: 140°F Spray Duration: 4 hr Water Chemistry: Boron, lithium hydroxide, hydrochloric acid 11/1/11 Pre-Licensing Meeting 15

Risk Informed GSI-191 Comparison to ICET Test 2 Inputs Ratio of STP Ratio of ICET STP Quantities to Test 2 Ratio Material Type Quantities* Max Pool Quantities to ICET/STP Volume Tank Volume Aluminum submerged 700 ft2 0.007834 ft2/ft3 0.179 ft2/ft3 22.8 Aluminum exposed to spray 6300 ft2 0.070509 ft2/ft3 3.34 ft2/ft3 47.4 Fiberglass insulation submerged 2385.1 ft3 0.026694 ft3/ft3 0.103 ft3/ft3 3.9 Marinite insulation submerged 15.2 ft3 0.00017 ft3/ft3 - 0.0 Microtherm insulation submerged 1.8 ft3 2.01E-05 ft3/ft3 - 0.0 Concrete submerged 5700 ft2 0.063794 ft2/ft3 0.015 ft3/ft3 0.2

• Quantities are taken from conservative inputs used in STP WCAP calculation, marinite removed, concrete only exposed to spray, etc.

11/1/11 Pre-Licensing Meeting 16

Risk Informed GSI-191 ICET Test Results 450 80 Test 1 unfiltered Test 5 unfiltered Alum minum concentration (mg/L) Alum minum concentration (mg/L) 400 70 Test 1 filtered Test 5 filtered 350 60 300 50 250 40 200 30 150 100 20 50 10 0 0 0 10 20 30 0 10 20 30 (a) Time (days) (b) Time (days)

Aluminum concentration below detection limit for Tests 2, 3, 4 Aluminum concentration leveled off over time for Tests 1, 5 Inverse trend between aluminum and silicon concentrations 11/1/11 Pre-Licensing Meeting 17

Risk Informed GSI-191 Alion Vogtle Vuez Test Results

• Minimal aluminum in solution

• No precipitates observed

• Head loss increased

~1 5x over 30 days

~1.5x days, possibly due to effect of fiber bed dissolution (NUREG/CR-6808)

Increasing head loss due to Nukon dissolution (reproduced from NUREG/CR-6808 Figure 7-23) 11/1/11 Pre-Licensing Meeting 18

Risk Informed GSI-191 Alion Vogtle and Calvert Cliffs HTVL Tests Vogtle Calvert Cliffs

• Buffer: TSP

• Buffer: NaTB

• Aluminum: 4 ppm

• Aluminum: 10 ppm

• Silica: 26 pp ppm

• Silica: 60 pp ppm

• pH: 7.6 - 7.8

• pH: 7.4

• Results: No precipitation

• Results: No precipitation at temperatures as low at temperatures as low as 128°F as 60°F 11/1/11 Pre-Licensing Meeting 19

Risk Informed GSI-191 Preliminary Ideas for Testing

• Perform integrated tests to determine material corrosion/dissolution/release rates and characterize precipitates in order to develop thermodynamics and kinetics models

• Perform benchtop or autoclave tests to further develop database for models

• Perform HTVL tests with replicated precipitates and varying debris loads to develop a chemical effects head loss algorithm 11/1/11 Pre-Licensing Meeting 20

Risk Informed GSI-191 Test Characterization of Precipitates

• VUEZ tests indicate precipitates form as crystals, with nucleation on fiberglass fibers, rather than amorphous precipitates forming in the pool as predicted by WCAP-16530 11/1/11 Pre-Licensing Meeting 21

Risk Informed GSI-191 Preliminary Ideas for Application to Risk Informed Analysis

• Use thermodynamics (and if possible) kinetics models to develop a chemical module for CASA Grande that can be used to calculate chemical precipitate types and quantities for any combination of parameters applicable to STP

• Develop a chemical effects head loss algorithm that can be incorporated in the head loss module for CASA Grande that is applicable to the ranges of chemical and non-chemical debris loads at STP 11/1/11 Pre-Licensing Meeting 22

Risk Informed GSI-191 Thermodynamics Modeling 1000 pH = 7.0 pH = 7.5 100 Solubility Limit for 10 Aluminum (mg/L) 1 0.1 40 60 80 100 120 140 160 180 200 220 Temperature (F) 11/1/11 Pre-Licensing Meeting 23

Risk Informed GSI-191 Chemical Head Loss Modeling

• Particulate Chemical Precipitate:

- NUREG/CR-6224 Head Loss Correlation

- Chemical particulate modeled as other particulates, i.e., surface to volume ratio and density

• Amorphous Chemical Precipitate:

- Develop a bump-up factor algorithm for low amorphous chemical precipitate to fiber loads

- Interpolate WCAP-16530 head loss testing results 11/1/11 Pre-Licensing Meeting 24

Risk Informed GSI-191 Validation of Chemical Precipitate Model

• Perform an Integrated 30 day test

- Realistic simulation of STP conditions:

• Temperature time history

• Materials exposed to spray

• Submerged material and debris

• Flow through a fiber bed

- Fluid analysis

- Weight loss measurements

- SEM of fiber bed 11/1/11 Pre-Licensing Meeting 25

Risk Informed GSI-191 Validation of Chemical Head Loss Model

• Perform Vertical Head Loss tests with chemical particulate simulant

- Compare Vertical Head Loss test results with NUREG/CR-6224 calculations

- Wide range of eta (particulate to fiber weight ratio)

- Wide range of debris bed thickness 11/1/11 Pre-Licensing Meeting 26

Risk Informed GSI-191 Conclusions

• Currently available data indicates that chemical effects at STP is far less severe than predicted by the standard WCAP-16530 methodology

• A combination of testing g and modeling g can be used to develop a realistic prediction of chemical effects for STP

• A chemical module and modified head loss module will need to be implemented into CASA Grande for evaluation of full range of scenarios 11/1/11 Pre-Licensing Meeting 27