MUR- Pre Monitoring Walk-down Findings (cont.)

MUR- Pre Monitoring Walk-down Findings (cont.)

MUR- Pre Monitoring Walk-down Findings (cont.)

MUR- Power Ascension

• MUR Power Ascension Occurred in 3 Steps of .5% RX Power Increase.

• After each Step a soak time of 1 hour was put in place for MUR Team to perform Post MUR walk-down.

• Unit 2 MUR was performed on 10/4/2010

• Unit 1 MUR was performed on 10/13/2010.

MUR- Power Ascension

• Unit 2 MUR post walk-downs did not identify any significant issues and was successfully completed.

• Unit 1 MUR post walk-downs during the three power ascension identified a change in the 11 FWP discharge line movement.

MUR- 11 FWP Movement Issue

• Prior to MUR, 11 FWP discharge pipe had movement of approximately 3/16 inches.

• NRC questioned (2/25/2010) this pipe interference with this pipe movement with concern of support bolt impacting FW pipe causing damage.

• Due to the thickness of the FW Pipe insulation (2”) with the minimal pipe movement, there was enough clearance to keep pipe from interface with hanger bolt.

MUR- 11 FWP Movement Issue (cont.)

MUR- 11 FWP Movement Issue (Cont.)

• During Unit 1 MUR 1st Power Ascension, 11 FWP pipe movement changed.

• Pipe movement ceased for a while and began to move in the same magnitude and frequency as identified during pre MUR walk-down.

• During second power accession, the pipe remained with the same cycle of stopping and moving. The magnitude increased slightly.

• During final power accession, the pipe swaying decreased to less than pre MUR accession.

MUR- Final Results

• Successful Completion of Unit 1 and Unit 2 MUR with an additional 8 MWe per Unit.

• Regulatory Margin was maintained with NRC during the two MUR evolutions.

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