ML070510476

Licensee Slides 2-9-07

ML070510476
Person / Time
Site:	Indian Point
Issue date:	02/09/2007
From:	ALION Science & Technology Corp, Enercon Services, Entergy Corp
To:	Office of Nuclear Reactor Regulation
Boska J, NRR, 301-415-2901
References
TAC MC4689, TAC MD4690
Download: ML070510476 (45)

Text

IPEC GSI-191 STATUS AND STRATEGY Presentation to the NRC February 9, 2007 1

ENERCON

AGENDA

• GSI-191 Project Team

• IP2/IP3 Sump Layout

• Sump Strainer Design

• GSI-191 Modifications

• Overall Methodology

• Design Basis and Pool Turnover

• Alternate Break Methodology

• Chemical Effects

• Path Forward

• GL 2004-02 Extension Request 2

• License Amendments ENERCON

GSI-191 Project Team

• Entergy Project Team

- Project Management, Engineering, Licensing, Nuclear Engineering Analysis, Construction Services

• Vendor Support

- Enercon

- Alion

- Transco

- Westinghouse 3

ENERCON

IP2/IP3 Sump Layout

• Two Independent and Redundant Sumps

- Internal Recirculation (IR) Sump - primary means of recirculation

- Vapor Containment (VC) Sump - backup to IR sump in case of loss of flow path

- IR Sump served by two IR pumps

- VC Sump served by two RHR pumps 4

ENERCON

Plan View of lower containment IR SUMP VC SUMP 5

ENERCON

Simplified ECCS Configuration RHR RHR PUMP PUMP IR IR PUMP PUMP M Valve IR SUMP VC SUMP 6

ENERCON

Sump Strainer Design

• Top Hat Characteristics

- Double Top Hat Strainer Module with Bypass Eliminator

- Perforated plate with 3/32 diameter hole

- Fiber Bypass expected to be less than 1 ft3 7

ENERCON

Top Hat Strainer Module 8

ENERCON

Debris Bypass Eliminator 9

ENERCON

Debris Bypass Eliminator Since most of the fiber is captured near the surface of the wire mesh material, very little fiber is observed at the ends of the mesh material exiting the strainer Top Hat modules 10 ENERCON

IP2 GSI-191 Modifications

• 2R17 Spring 2006 Refueling Outage

- Installation of Sump Strainers

• ~3200 ft2 Installed in IR Sump (original 48 ft2)

• ~440 ft2 Installed in VC Sump (original 14 ft2)

• Maximized surface area in sumps 11 ENERCON

IP2 IR Sump Strainer 12 ENERCON

IP2 IR Sump Strainer 13 ENERCON

IP2 VC Sump Strainer 14 ENERCON

IP2 VC Sump Strainer 15 ENERCON

IP2 GSI-191 Modifications (Contd)

Installation of Flow Channeling Modifications

• In-core tunnel

• Crane wall holes

• Gates and barriers 16 ENERCON

Flow Channeling Concept Debris Transport is Reduced by Flow Channeling Concept

• Flow Channeling

- Step 1: Water inside the crane wall flows to the Reactor Cavity

- Step 2: Water travels through the Incore Instrumentation Tunnel where a majority of the debris settles

- Step 3: Relatively clean water travels to the sumps 17 ENERCON

Flow Channeling Concept 18 ENERCON

Flow Channeling Concept IP2 North Incore Tunnel Exit Flow Barrier 19 ENERCON

IP3 GSI-191 Planned Modifications

• 3R14 Spring 2007 Refueling Outage

- Installation of Sump Strainers

• ~3200 ft2 Installed in IR Sump (original 48 ft2)

• ~1000 ft2 Installed in VC Sump (original 32 ft2)

• Maximized surface area in sumps

- Installation of Flow Channeling Modifications

• In-core tunnel

• Crane wall holes

• Gates and barriers 20

• Screens on penetrations ENERCON

IP3 IR Sump Strainer IP2 and IP3 IR Sump Strainers are Virtually Identical 21 ENERCON

IP3 VC Sump Strainer 22 ENERCON

OVERALL METHODOLOGY

- Debris Identification

- Debris Generation

- Debris Transport

- Downstream Effects

- Testing 23 ENERCON

Debris Identification

• Insulation

- Calsil/Asbestos, Temp-Mat, Nukon, Transco blanket, RMI, Mineral Wool, Kaowool

• Coatings

- Epoxy, Inorganic zinc, Enamel, High temperature aluminum, Phenoline

• Latent Debris

- Tape & Equipment labels, Tie wraps, Fiber board tags, Dirt & Dust, Latent Fiber 24 ENERCON

Debris Generation 25 ENERCON

Debris Transport Vectors showing pool flow direction on the floor 26 ENERCON

Debris Transport Vectors of pool flow direction in the Incore Tunnel 27 ENERCON

Debris Transport Determination

• The turbulence and vertical velocity are compared to the turbulent kinetic energy (TKE) and velocity metrics to suspend each kind of debris

• 3-D CFD plots show the turbulence and z velocities

• If TKE or vertical velocities not high enough - the debris would settle in tunnel

• Results show that most debris settles in the tunnel 28 ENERCON

Downstream Effects

• Evaluation of Components

- Blockage of small flow paths

- Seizure of rotating components

- Wear and abrasion of surfaces

• Evaluation of Reactor Vessel and Fuel

- Reactor vessel flow paths

- Nuclear fuel

• No Downstream Effects Concerns Identified to Date 29 ENERCON

Testing

• Dissolution / Erosion Measurement of Cal-Sil

• Array Head Loss for Debris

• Fiber Bypass

- Fiber Bypass testing of a prototypical module

- Bypass material characterization 30 ENERCON

Current Design Basis

• Indian Points ECCS configuration is unique in that it has two independent and redundant sumps

• No single active failure will disable the IR Sump and only a passive failure will require the use of the VC Sump

• The VC Sump is not in itself single active failure protected, however, once a passive failure has occurred no more active failures would need to be considered 31 ENERCON

Current Design Basis No single active failure will disable the IR Sump RHR RHR PUMP PUMP IR IR PUMP PUMP M Valve IR SUMP VC SUMP 32 ENERCON

Current Design Basis Only a passive failure will require the use of the VC Sump RHR RHR PUMP PUMP IR IR PUMP PUMP M Valve IR SUMP VC SUMP 33 ENERCON

Current Design Basis The VC Sump is not in itself single active failure protected RHR RHR PUMP PUMP IR IR PUMP PUMP M Valve IR SUMP VC SUMP 34 ENERCON

Alternate Break

• The Alternate Break Methodology as accepted by the SER allows no single failure for breaks larger than 14 (Large Break, LBLOCA) but requires design basis rules for breaks smaller than 14 (Alternate Break, ABLOCA)

• This approach allows the VC Sump design to be limited to ABLOCA debris loads with credit for Pool Turnover 35 ENERCON

Pool Turnover Strategy

• At start of recirculation the IR Sump will be in operation. VC Sump will be in stand-by

• A passive failure of the IR Sump is postulated to occur no earlier than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after the start of recirculation

• Greater than 95% of the transportable debris would be collected at the IR Sump strainer

• The VC sump strainer would be essentially clean at this time and would provide necessary recirculation cooling 36 ENERCON

37 ENERCON

Alternate Break Methodology IP2/3 (Without Chemical Effects)

• LBLOCA (no single failure required to be assumed)

- IR Sump can handle LBLOCA debris load (including a single active failure)

- VC Sump can handle LBLOCA debris load after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of IR Sump recirculation

• ABLOCA (single failure required to be assumed)

- IR Sump can handle ABLOCA debris load including a single active failure

- VC Sump can handle ABLOCA debris load following 24 hrs of IR Sump recirculation assuming a passive failure of IR system 38 ENERCON

Chemical Effects

• TSP (IP2 only) and Cal-Sil

- Results in Calcium Phosphate formation

• TSP/NaOH and Aluminum (IP2 & IP3)

- Results in Sodium Aluminum Silicate formation 39 ENERCON

Chemical Effects with Alternate Break Methodology

• LBLOCA (no single failure required to be assumed)

- IR sump will handle debris + chemical loads for at least 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (including a single active failure)

- VC sump will handle residual debris + chemical loads following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of IR Sump recirculation

• ABLOCA (single failure required to be assumed)

- IR Sump will handle debris + chemical loads for at least 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> including a single active failure

- VC sump will handle residual debris + chemical loads following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of IR sump operation with a postulated passive failure of IR system.

- If IR sump cannot survive long term with debris + chemical loads, then VC sump must be utilized. 40 ENERCON

Chemical Effects Options

- Reduce debris amounts such that chemical precipitants may pass through the strainer

- Reduce precipitate formation by PWROG WCAP model refinement

- Reduce Aluminum quantity exposed to spray

- Autoclave Testing to determine precipitate formation as function of time

- Replace buffer

- Batch buffer 41 ENERCON

Path Forward

• Debris Generation

- ZOI Refinements for Nukon, Temp Mat, Mineral Wool

- Coatings fail as chips

- Remove Kaowool (IP3)

• Chemical Effects Options

• Extension Requests and License Amendments 42 ENERCON

GL 2004-02 Extension Request

• IP2

- 2R18 Spring 2008 Refueling Modifications

• Buffer replacement or batching

• Screens on crane wall penetrations

• IP3

• None required (Pending Chemical Refinements) 43 ENERCON

License Amendments

• IP2

- Buffer replacement/batching

- Alternate Break

- 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> delay time for passive failure

• IP3

- Buffer replacement/batching

- Alternate Break

- 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> delay time for passive failure

- RWST switchover level TS change 44 ENERCON

End of Presentation 45 ENERCON