ML082890357

Meeting Slides, Monticello Extended Power Uprate Resubmittal

ML082890357
Person / Time
Site:	Monticello
Issue date:	10/15/2008
From:	Xcel Energy
To:	Office of Nuclear Reactor Regulation
Tam P
References
TAC MD9305
Download: ML082890357 (10)

Text

, Monticello Extended Power l.----__-----...J Uprate Resubmittal NRC Meeting October 15, 2008 Meeting Agenda

Background

Steam Dryer Analysis Equipment Qualification Setpoint Methodology Grid Stability Study Changes to the LAR Overall Schedule Summary

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Background===

• EPU LAR Submittal 3/31/08

• LAR withdrawn on 6/25/08

• Three items

- Steam Dryer Evaluation

- Equipment Qualification

- Instrument Setpoint Methodology EPU Project Principles

• Maintain or improve safety and risk profile Improve or enhance equipment reliability Follow existing regulatory processes Use industry operating experience Coordinate with License Renewal and Life Cycle Management projects lVIin imize the impact on day-to-day operation

- Extract value from standardization, economies of scale, with minimal duplication

Plant Background

• GE BWR 3

• 1971 began operation at 1670 MWt (OLTP)

• 1998 increased power to 1775 MWt (CLTP)

• 2008 EPU application to 2004 MWt (120%

OLTP)

- Power increase in two stages

• After EPU approval - Increase to approximately 1870 MWt

• After 2011 outage - Increase to full EPU at 2004 MWt Monticello Steam Dryer Information

• GE 1965 Product Line, Square Hood

• Steam dryer licensing basis accident is main steam line break outside of containment

• Steam dryer inspection per Boiling Water Reactor Vessel Internals Project (BWRVIP 139)

Industry Steam Dryer Information

• EPRI and BWRVIP initiative to provide a consistent steam dryer evaluation method:

- BWRVIP-182 for steam dryer evaluation methodologies (Submitted January 30, 2008)

- Continuum Dynamics Incorporated (COl) licensing topical report (planned submittallate-2008)

- RG 1.20, Revision 3

• 90 day startup reporting exception Monticello Steam Dryer Evaluation Approach Steam Dryer Analysis (BWRVIP-182)

Screening of suscept ibility to acoustic excitation validated by scale model tests Strain gage measurements of CLTP main steam line (MSL) acoustics Acoustic circuit model (ACM) of steam dome Load definition at CLTP Finite Element Model (FEM) of dryer at CLTP Limit curves for EPU power ascension

MSL Data

• Strain Gage data taken in 2007 at 28% and 100%

CLTP, and during recent startup

• Filters applied for pipe bending, recirc pump electrical and vane passing frequency noises

• Submodel analysis applied

• Bias and uncertainty applied per COl LTR Dryer Evaluation Results

• SRV standpipe resonant frequency approximately 162 Hz at CLTP

• EPU steam velocity of 179 ft/sec is below the lowest calculated resonance onset velocity of 185 ft/sec

• Scale model test acoustic resonance velocity is 201 ft/sec

• CLTP minimum alternating stress ratio is >2.0

• EPU minimum alternating stress ratio is >2.0

Steam Dryer Flaw Evaluation

• There is no effect on component stiffness and modal response due to cracking.

• The potential for crack growth due to fatigue is minimal.

Steam Dryer Summary

• Evaluated per BWRVIP-182 and COl LTR

• The impacts of flaws and flaw growth are evaluated

• Minimum alternating stress ratio is > 2.0

Equipment Qualification

• MNGP has completed the environmental qualification analyses

• Results show that two transmitter modifications are required for EPU implementation

- Modification paperwork complete by submittal

• EO files for 10CFR50.49 qualification will be complete prior to EPU implementation Instrument Setpoint Calculation Methodology

• MNGP employs NRC approved GE Setpoint Methodology

• Setpoints are calculated from the analytical limit (AL)

• Margins calculated between the AL and the allowable value (AV) and between the AV and the nominal trip set point (NTSP)

Instrument Setpoint Calculation Methodology

• ALIAV margin includes measurement accuracy, primary element accuracy, instrument loop accuracy and calibration errors

• AV/NTSP margin includes loop accuracy under calibrated conditions, calibration errors and drift errors Instrument Setpoint Calculation Methodology

• Two Setpoints are calculated

- ALINTSP1 contains all errors and is equivalent to the limiting trip setpoint (LTS) in RIS 2006-17 NTSP2 is calculated to provide 90% confiden ce the AV is not exceeded during surveillance tests

• The final setpoint is selected to satisfy both NTSP1 and NTSP2 and is equivalent to the nominal setpoint in RIS 2006-17

instrument Setpoint Calculation Methodology

• Examples of as found and as left tolerances (AFT and ALT) are included in sample calculations

• IVINGP procedures require shift manager determination of immediate operability if an instrument is found to be out of tolerance

• The condition is entered into the corrective action process if the AFT is exceeded

• All setpoints are reset to the NTSP within the ALT after calibration L-XcelEnergy-Grid Stability Study

• Study completed for both stage I (1870MWt) and stage II (2004 MWt)

• No impact on grid stability at either power level

• MISO interconnection tariff requires the maintenance of 0.95 leading/lagging power factor capability

Changes to the LAR

• Non-Acceptance Open Items Addressed

• Acceptance Review Questions Documented

• Industry RAls Evaluated

• Steam Dryer Submittal Enhanced

• Grid Stability Summary Completed 2007 D FIV Monhoring Modificat ions for EPU Montice 10 chedule I

2009 D Refueling Outage

"" I I

EPU '0 2004 MWt 2010 2011 2008 DRefueling Outage I

PRNMS& Srablllty Option III

~

EPUto 1 ~ 7 D MW OSS~D Stability '"

Solution LAR I

I MELLLA+ LAR I

I PRNMS lnstaltaticn & EPU PhaseI Modifications.6. EPU Ph.se 11

.. - Submrttal

... = NRC Approval

... ;; Withdrawn durtngAcceptance

.... Implementation

Summary

• MNGP EPU LAR will be submitted early November 2008

• Addresses prior NRC items

• Considers RAl's from previous submittals Questions?