ML061670164

Slides, Summary of Conference Calls 117438

ML061670164
Person / Time
Site:	Prairie Island
Issue date:	07/10/2006
From:	Nuclear Management Co
To:	Office of Nuclear Reactor Regulation
Mahesh Chawla, LPL3-1, 415-8371
Shared Package
ML06168005	List: ML061670164
References
FOIA/PA-2010-0209, TAC MD1784
Download: ML061670164 (19)

Text

Prairie Island Unit I R24 Outage*

NRC Phone Call and NRC Discussion Points**

May 18, 2006

• The attached information has not been validated. In many cases, it is preliminary information from ongoing activities. To our knowledge, it is the best information available as of 6 PM on the date prior to this report and may be changed following further review and analysis.

• • 2R23 NRC Discussion Points used as template for this presentation.

PI 1R24 SG NRC Phone Call I

Participants

° Ben Stephens (PI SG Program Engineer)

• Richard Pearson (PI alternate SG Engineer)

" Scott Redner (PI SG NDE Level Ill)

° Jeff Kivi (PI Licensing)

° Kari DenHerder (PI SG HIT Lead)

° Scott McCall (PI Engineering Programs Manager)

• Steve Brown (PI Engineering Director)

PI 1R24 SG NRC Phone Call 2

Current Status of 1 R24 ISI SGI nspection (As of 1800 on May 17, 2006)

Category 11 SG 12 SG Acquisition 100 100

(% completed)

Analysis 100 100

(% completed)

1. of Pluggable 0 3 Tubes

1. of In Situ 0 0 Candidates PI 1R24 SG NRC Phone Call 3

Q1: Discuss any trends in the amount of primary-to-secondary leakage observed during the recently completed cycle.

°11 Steam Generator maximum steady state leakage by tritium was 0.7 gallons per day over the last cycle

• 12 Steam Generator maximum steady state leakage by tritium was 0.8 gallons per day over the last cycle

• Leak rate based on Argon was less than detectable over the last cycle PI 1R24 SG NRC Phone Call 4

Q2: Discuss whether any secondary side pressure tests were performed during the outage and the associated results.

> None were planned or performed PI 1R24 SG NRC Phone Call 5

Q3: Discuss any exceptions taken to the industry guidelines.

>No exceptions will be taken from industry guidelines.

PI 1R24 SG NRC Phone Call 6

Q4: For each SG, provide a description of the inspections performed including the areas examined and the probes used (e.g., dents/dings, sleeves, expansion-transition, U-bends with a rotating probe), the scope of the inspection (e.g., 100 percent of the dents/dings greater than 5 volts and a 20 percent sample between 2 and 5 volts), and the expansion criteria. Also, discuss the extent of the rotating probe inspections performed in the portion of the tube below the expansion transition region (reference NRC Generic Letter 2004-01, "Requirements for Steam Generator Tube Inspections").

> Prairie island 1R24 steam generator inspection plan is attached on the following sheet.

PI 1R24 SG NRC Phone Call 7

Inspection Plan SCOPE PROBE TYPE S/G 11 S/G 12 Full Length Bobbin 100% 100%

Rows 1 through 9 U-Bends MRPC 0% 0%

Hot Leg Tubesheet MRPC 0% 0%

Cold Leg Tubesheet MRPC 0% 0%

Post In Situ Pressure Test MRPC 100% 100%

SupplementalO MRPC -500 -320 O Supplemental MRPC testing is based on both baseline and current results: Inspect all baseline GMD, PVN, SVI, and percent calls. Inspect all current BLG > 1.0, CUD, DEP, DNG > 1.0, DNI, DSI, DTI, INR

> 1.5 V @ TSP's, MBM, NQI, OXP, PDS, PLP, and percent calls.

0 Approximate number of tubes based on baseline results.

PI 1R24 SG NRC Phone Call 8

Q5: For each area examined (e.g., tube supports, dents/dings, sleeves, etc), provide a summary of the number of indications identified to-date of each degradation mode (e.g., number of circumferential primary water stress corrosion cracking indications at the expansion transition).

For the most significant indications in each area, provide an estimate of the severity of the indication (e.g., provide the voltage, depth, and length of the indication). In particular, address whether tube integrity (structural and accident induced leakage integrity) was maintained during the previous operating cycle. In addition, discuss whether any location exhibited a degradation mode that had not previously been observed at this location at this unit (e.g.,

observed circumferential primary water stress corrosion cracking at the expansion transition for the first time at this unit).

PI 1R24 SG NRC Phone Call 9

Analysis Status Analysis Status (percent completed) SG 11 SG 12 as of 1800 on May 17, 2006:

Hot Cold Hot Cold Tubesheet Crevice MRPC N/A N/A N/A N/A Bobbin 100 100 100 100 U-Bend MRPC N/A N/A N/A N/A Special Interest MRPC 100 100 100 100 (Actual Tests) (139) (59) (90) (61)

PI 1R24 SG NRC Phone Call 10

SG 11 Analysis Results to Date Degradation Mode and Location # Volt Depth Length New TSP Tapered Wear (volumetric) 56 0.15 13 0.82 Y AVB Wear (volumetric) 9 0.21 7 0.59 Y Structural and accident induced leakage integrity was maintained during the previous cycle PI 1R24 SG NRC Phone Call I1I

SG 12 Analysis Results to Date Degradation Mode and Location # Volt Depth Length New TSP Tapered Wear (volumetric) 7 0.29 21 1.27 Y AVB Wear (volumetric) 32 0.24 8 0.62 Y PLP (confirmed) - 1 N/A N/A N/A Y Structural and accident induced leakage integrity was maintained during the previous cycle PI 1R24 SG NRC Phone Call 12

Q6: Describe repair/plugging plans.

Predicted Repairs SCOPE S/G 11 S/G 12 In Situ Pressure Test 0 0 Hot Leg Roll Plugs 0 0 Cold Leg Roll Plugs 0 0 PI 1R24 SG NRC Phone Call 13

Q6: Describe repair/plugging plans.

Required Repairs SCOPE S/G 11 S/G 12 In Situ Pressure Test 0 0 Hot Leg Roll Plugs 0 3 Cold Leg Roll Plugs 0 3 S*Plugged R5 5 C5 8 for 21% at 03H and 15% at 05C

• Plugged R3l C104 for 19% at 03C ePlugged R40 C20 for PLP at 01H PI 1R24 SG NRC Phone Call 14

Q7: Describe in-situ pressure test and tube pull plans and results (as applicable and if available).

>We have no plans to pull tubes for unit 1, as part of a licensed repair program.

> Status - No tube pull needed.

>We have no plans on performing in situ tests.

> Status - No in situ needed.

PI 1R24 SG NRC Phone Call 15

Q8: Provide the schedule for steam generator-related activities during the remainder of the current outage.

>ET examinations were completed on May 10.

>In-situ testing is not required

>Repairs were completed on May 12

>Installed primary manways May 13 PI 1R24 SG NRC Phone Call 16

Q9: Discuss the following regarding loose parts: 1) what inspections are performed to detect loose parts, 2) a description of any loose parts detected and their location within the SG, 3) ifthe loose parts were removed from the SG, 4) indications of tube damage associated with the loose parts, 5) the source or nature of the loose parts, if known PI 1R24 SG NRC Phone Call 17

A) All bobbin data is evaluated for possible loose parts (PLP) and PLP wear using manual analysis by primary.

B) Secondary uses Computer Data Screening (CDS) with a PLP specific sort and various wear detection sorts.

C) All MRPC data is evaluated for PLP's.

D) All bobbin PLP indications are tested with MRPC.

E) All PLP indications are bounded radially by one tube at the same elevation.

F) A Foreign Object Search and Retrieval Inspection (FOSAR) was completed on the secondary side on top of the tubesheet using fiberscope equipment.

G) The Loose Part Trapping Screens in the downcomer were inspected to ensure that they were intact and clear of foreign material PI 1R24 SG NRC Phone Call 18

2. A) SG 11 had 2 bobbin PLP indications on the top of the hot leg tube sheet not confirmed by MRPC.

B) SG 12 had 1 bobbin PLP indication at the first tube support plate on the hot leg side confirmed by MRPC.

3. A) SG 11 secondary side FOSAR is complete.

B) SG 12 secondary side FOSAR is complete.

4. A) SG 11 has no indication of wear associated with PLP's.

B) SG 12 has no indication of wear associated with PLP's.

5. A) SG 11 PLP indications are bobbin false positives.

B) SG 12 PLP was a possible machine chip.

PI IR24 SG NRC Phone Call 19