ML13176A133

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June 26, 2013 Public Meeting Slides Concerning D.C. Cook Unit 1 LAR to Return to Normal Operating Pressure and Temperature
ML13176A133
Person / Time
Site: Cook American Electric Power icon.png
Issue date: 06/25/2013
From: Hafer D, Hill G, Lies Q, Scarpello M
Indiana Michigan Power Co
To:
Division of Operating Reactor Licensing
Wengert T
References
TAC MF1973
Download: ML13176A133 (15)


Text

D. C. Cook Nuclear Plant Unit 1 Return to Normal Operating Pressure and Temperature (NOP/NOT)

June 26, 2013 Q. Shane Lies Gregory J. Hill Engineering Vice President Nuclear Safety Analysis Michael K. Scarpello Donald R. Hafer Nuclear Regulatory Affairs Sargent & Lundy Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant

Meeting Objectives

  • Brief Staff on License Amendment Request

- Return Unit 1 reactor coolant system (RCS) to its previously licensed operating pressure and temperature (NOP/NOT)

  • Solicit Staff Feedback Enhance nuclear safety by ensuring SG reliability throughout plant life Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 2

Meeting Agenda

  • Problem and Solution
  • License Amendment Request

- Overview and impacts

- Application of TSTF493

- LAR content

  • Proposed Schedule
  • Staff Feedback Foster open and effective communications between AEP and NRC Staff Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 3

Problem

  • Operating History NOP/NOT

- Operating temperature and 600 pressure reduced in 1990 550

- Steam generators (SGs) replaced in 2000 500

% Reactor Power 0 100

  • 2011 SG Inspection Results

- Tube wear at fan bar supports Reduced Temp & Press

- Resonancerelated tube 600 vibration due to low steam pressure 550 500 0  % Reactor Power 100 Enhance nuclear safety by ensuring SG reliability throughout plant life June 26, 2013 4

SG Tube Fan Bar Wear

  • Wear Due to TubetoSupport Rubbing

- No midspan tubetotube wear

- No inplane fluid elastic instability

  • Wear Rate is Low

- New SGs operated for seven cycles (8.35 EFPY) before wear scars were detected

- Spring 2013 inspection confirms that the wear rate is low, but still continuing

  • Limited Extent

- Only the subset of tubes with relatively long free spans between fan bar support points are affected Fan bar wear represents a concern for longterm reliability of the Unit 1 SGs Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 5

Solution

  • Corrective Action from Root Cause Evaluation

- Eliminate resonance by raising SG steam pressure

- Restore RCS to NOP/NOT

  • Primary pressure: 2250 psia
  • Primary temperature (TAvg): 575oF Enhance nuclear safety by ensuring SG reliability throughout plant life Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 6

License Amendment Overview

  • Return to Previously Licensed Conditions

- Impact on accident analyses

  • Analysesofrecord generally support NOP/NOT
  • Response to 10 CFR 50.54(f) letter regarding Thermal Conductivity Degradation is affected

- Impact on Tech Specs

- Plant Changes

  • Implement TSTF493 NOP/NOT enhances SG reliability TSTF493 addresses Staff generic concerns with setpoint methodology Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 7

AnalysesofRecord Impacts

  • Best Estimate LOCA - Peak Clad Temperature
  • Containment Integrity
  • Containment Inventory (Sump Level)
  • SGTR MargintoOverfill
  • Dose Analyses - LOCA Enhance nuclear safety by ensuring SG reliability throughout plant life Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 8

Tech Spec Impacts - NOP/NOT

- Change low pressurizer pressure reactor trip setpoint

- Change applicable RCS pressure range

- Change applicable RCS pressure range

- Revise time range for CEQ fan start Enhance nuclear safety by ensuring SG reliability throughout plant life Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 9

Tech Spec Impacts - TSTF493

- Add standard notes

  • Table 3.3.21, ESFAS Instrumentation

- Add standard notes

- Change high steam flow values from lb/hr to percent

  • Bases

- Add standard notes Address Staff generic concerns with setpoint methodology Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 10

Plant Changes

  • Physical Changes

- Setpoints

- Timing relays

- Control Room indication

- Unit 1 simulator

  • Procedures Enhance nuclear safety by ensuring SG reliability throughout plant life Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 11

TSTF493, Rev. 4

- Industry and NRC expectation to implement TSTF493

  • Full Implementation of Option A

- Unit 1 only

  • Submittal

- Separate or combined?

- Process for calculation review Addresses Staff generic concerns with setpoint methodology Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 12

LAR Content

  • Tech Spec Changes
  • No Significant Hazards Consideration

- WCAP containing results of Chapter 14 accident evaluations and analyses

- Updated response included as attachment

  • TSTF493 Submittal Foster open and effective communications between AEP and NRC Staff Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 13

Proposed Schedule Milestone Date Hold presubmittal Public Meeting Jun 26,2013 Confirm accident analysis results Aug 2013 Complete WCAP and I&C calculations Sep 2013 Submit LAR(s) (target date) Oct 10, 2013 NRC accept submittal Nov 2013 NRC complete review Jul/Aug 2014 Issue License Amendment (target date) Aug 15, 2014 Start U1C26 refueling outage Sep 24, 2014 Facilitate timely processing of a License Amendment to enhance nuclear safety Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 14

Discussion/Questions Foster open and effective communications between AEP and NRC Staff Indiana Michigan Power Nuclear Generation Group Cook Nuclear Plant June 26, 2013 15