GNRO-2017/00039, Steam Dryer Visual Inspection Results for the First Two Scheduled Refueling Outages

Steam Dryer Visual Inspection Results for the First Two Scheduled Refueling Outages

ML17186A023
Person / Time
Site:	Grand Gulf
Issue date:	06/30/2017
From:	Emily Larson Entergy Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
GNRO-2017/00039, TAC ME4679
Download: ML17186A023 (9)

Text

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~Entergy Entergy Operations, Inc.

P.o. Box 756 Port Gibson, MS 39150 Eric A. Larson Vice President, Operations Grand Gulf Nuclear Station Tel. (601) 437-7500 GNRO-2017/00039 June 30, 2017 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike Rockville, MD 20852

SUBJECT:

Steam Dryer Visual Inspection Results for the First Two Scheduled Refueling Outages Grand Gulf Nuclear Station - Unit 1 Docket Nos. 50-416 License Nos. NPF-29

REFERENCES:

1. Entergy letter to NRC, License Amendment Request, Extended Power Uprate, dated September 8, 2010 (GNRO-2010/00056, Accession Number ML102660403)

2. NRC Letter to Entergy Operations, Inc., Grand Gulf Nuclear Station, Unit 1- Request for Additional Information Regarding Extended Power Uprate Application License Amendment Request (TAC NO. ME4679) dated March 2,2011 (Accession Number ML110550475)

3. Entergy letter to NRC, [Response to] Request for Additional Information Regarding Extended Power Uprate, Grand Gulf Nuclear Station, Unit 1, dated March 30, 2011 (GNRO-2011/00018) (ML110900275)

4. NRC Letter to Entergy Operations, Inc., Grand Gulf Nuclear Station, Unit 1 - Issuance of Amendment RE: Extended Power Uprate, dated July 18, 2012 (TAC NO. ME4679)

(ML121210020)

5. BWRVIP-139-A BWR Vessel and Internals Project, Steam Dryer Inspection and Flaw Evaluation Guidelines, 1018794, July 2009

Dear Sir or Madam:

Grand Gulf Nuclear Station (GGNS) conducted visual inspections of all accessible locations of the steam dryer in accordance with the BWRVIP-139-A, Steam Dryer Inspection and Flaw Evaluation Guidelines, and General Electric's (GE) inspection guidelines. Attached are the summary results of the visual inspections conducted in the first two refueling outages (RF19; 2014 and RF20; 2016) after reaching full Extended Power Uprate (EPU) conditions. This letter is being submitted in accordance with Operating License No. NPF-29, Condition 2.C(46)(f).

GNRO-2017/00039 Paqe 2 of 3 This letter contains no new Regulatory Commitments.

Should you have any questions concerning the content of this letter, please contact James Nadeau at 601-437-2103.

I declare under penalty of perjury that the foregoing is true and correct. Executed on June 30, 2017.

Sincerely, Eric A. Larson Site Vice President Grand Gulf Nuclear Station EAUsas

Attachment:

Grand Gulf Nuclear Station Steam Dryer Visual Inspection Results for the First Two Scheduled Refueling Outages after Reaching Full EPU Conditions cc: see next page

GNRO-2017/00039 Page 3 of 3 cc: U.S. Nuclear Regulatory Commission ATTN: Mr. Siva Lingham Mail Stop OWFN 8 81 Rockville, MD 20852-2738 U.S. Nuclear Regulatory Commission ATTN: Mr. Kriss M. Kennedy Regional Administrator, Region IV 1600 East Lamar Boulevard Arlington, TX 76011-4511 Mr. B. J. Smith Director, Division of Radiological Health Mississippi State Department of Health Division of Radiological Health 3150 Lawson Street Jackson, MS 39213 NRC Senior Resident Inspector Grand Gulf Nuclear Station Port Gibson, MS 39150

Attachment to GNRO-2017/00039 Grand Gulf Nuclear Station Steam Dryer Visual Inspection Results for the First Two Scheduled Refueling Outages after Reaching Full EPU Conditions

Attachment to GNRO-2017/00039 Page 1 of 5 Introduction As required by the staff's Safety Evaluation (SE) for Amendment 191 to the Facility Operating License No. NPF-29 for the Grand Gulf Nuclear Station, Unit 1 dated July 18, 2012, Grand Gulf conducted visual inspections of all accessible locations of the steam dryer in accordance with the BWRVIP-139-A, Steam Dryer Inspection and Flaw Evaluation Guidelines, and General Electric's inspection guidelines. These inspections were conducted during the first two scheduled refueling outages (RF19; 2014 and RF20; 2016) after reaching full Extended Power Uprate (EPU) conditions. Grand Gulf's proposed long term steam dryer inspections plan will be submitted in a separate report.

In total over 500 inspections were recorded on the steam dryer outer diameter, and over 350 inspections were recorded on the steam dryer inner diameter. The inspection method used for the steam dryer inspections were VT-3 and VT-1. The VT-1 inspections were performed using the VT-1-1/32 method which is a VT-1 quality examination that visually resolves a 1/32" black line on an 18% neutral gray card as required by BWRVIP-139-A.

RF19 (2014) Inspection Results The first scheduled refueling outage after reaching full EPU conditions was RF19. During this refueling outage, the first set of baseline inspections on the replacement steam dryer was conducted. No relevant indications were observed on any of the steam dryer inner diameter inspection locations in RF19. Relevant indications on steam dryer outer diameter inspection locations are listed below in Table 1. Re-inspections of the indications were scheduled for and completed in RF20 to confirm no significant changes occurred.

Table 1: RF19 Relevant Indications Component Name Component Inspection Results Corrective Actions Description Type and Re-Inspection SDOD BC TRB 01 Bank C Azimuth VT-1-1/32 Abnormal Trend. Indication due 0° Tie Rod discoloration on the to construction Bolting bottom weld and damage on the washer bolt head and subsequent crud buildup on the damaged washer Re-inspect in RF20 SDOD LG 000 0° Azimuth Lower VT-1-1/32 Witness/rub marks Trend. No evidence of Guide Surfaces were observed on metal slivers or rolled the inner surfaces metal Indications consistent with steam dryer installation and/or removal from the vessel Re-inspect in RF20

Attachment to GNRO-2017/00039 Page 2 of 5 SDOD SSB 120 120 0 Azimuth VT-1-1/32 Wear observed on Seismic Support Block Seismic Support the lead in surfaces polished to remove the Block metal slivers.

Indications consistent with handling marks during steam dryer installation and/or removal from the vessel.

Re-inspect in RF20 SDOD SSB 185 185 0 Azimuth VT-1-1/32 Wear observed on Seismic Support Block Seismic Support the lead in surfaces polished to remove the Block metal slivers.

Indications consistent with handling marks during steam dryer installation and/or removal from the vessel.

Re-inspect in RF20 SDOD SSB 240 240 0 Azimuth VT-1-1/32 Wear and gouges Seismic Support Block Seismic Support observed on the polished to remove the Block lead in surfaces metal slivers.

Indications consistent with handling marks during steam dryer installation and/or removal from the vessel.

Re-inspect in RF20

Attachment to GNRO-2017/00039 Page 3 of 5 RF20 (2016) Inspection Results The second scheduled refueling outage after reaching full EPU conditions was RF20. During this refueling outage, the second and final set of baseline inspections on the replacement steam dryer was conducted. No relevant indications were observed on any of the steam dryer inner diameter inspection locations in RF20. Two new relevant indications were observed on steam dryer outer diameter inspection locations. These indications are listed below in Table 2.

Table 2: RF20 Relevant Indications Component Component Inspection Results Corrective Actions Description Type and Re-inspection SDOD SSB 240 240 0 Azimuth VT-1-1/32 New wear observed Seismic Support Block Seismic Support on the lead in polished to remove the Block surfaces (this wear metal slivers.

is in a different location on the lead Indications consistent in surface than the with handling marks previously identified during steam dryer indication) installation and/or removal from the vessel.

Re-inspection scheduled for RF21 SDOD SSB 300 300 0 Azimuth VT-1-1/32 Wear observed on Seismic Support Block Seismic Support the lead in surfaces polished to remove the Block metal slivers.

Indications consistent with handling marks during steam dryer installation and/or removal from the vessel.

Re-inspection scheduled for RF21

Attachment to GNRO-20 17/00039 Page 4 of 5 Re-Inspection of Previously Identified Indications All relevant indications observed in RF19 were re-inspected in RF20 to identify any changes.

The re-inspection results are shown below in Table 3. In summary, the indication on SDOD SSB 120 showed additional wear on the lead in surfaces, and all other indications showed no discernable changes. All indications are scheduled for re-inspection in RF21 to confirm no significant changes have occurred. Relevant indications will continue to be inspected each refueling outage until the indication is shown to have stabilized. This is typically established with two subsequent re-inspections with no changes noted after the indication is initially identified.

Once an indication is shown to have stabilized, inspections will continue at the regularly scheduled frequency.

Table 3: RF20 Re-Inspection of Previously Identified Indications Component Component Inspectio Results Corrective Actions Descri ption n Type and Re-inspection SDOD BC TRB 01 Bank C Azimuth VT-1-1/32 No discern able Trend 0 Tie Rod Bolting 0

changes noted Re-inspection scheduled for RF21 SDOD LG 000 0 0 Azimuth Lower VT-1-1/32 No discernable Trend Guide Surfaces changes noted Re-inspection scheduled for RF21 SDOD SSB 120 120 0 Azimuth VT-1-1/32 Additional wear Seismic Support Block Seismic Support observed on the lead polished to remove the Block in surfaces metal slivers.

Indications consistent with handling marks during steam dryer installation and/or removal from the vessel.

Re-inspection scheduled for RF21 SDOD SSB 185 185 0 Azimuth VT-1-1/32 No discern able Trend Seismic Support changes noted Block Re-inspection scheduled for RF21 SDOD SSB 240 240 0 Azimuth VT-1-1/32 No discernable Trend Seismic Support changes noted on Block the original location. Re-inspection scheduled for RF21 Additional wear observed on the lead in surfaces as noted in Table 2.

Attachment to GNRO-2017/00039 Page 5 of 5 Conclusion A complete baseline inspection of the Gran Gulf replacement steam dryer was performed during the two subsequent refueling outages (RF19 and RF20) following full EPU conditions. The baseline inspections were consistent with the guidance provided in BWRVI P-139-A, Steam Dryer Inspection and Flaw Evaluation Guidelines, and General Electric's inspection guidelines.

Based on engineering evaluation, it was concluded that none of the steam dryer indications identified in RF19 or RF20 challenge the structural integrity or function of the steam dryer. This completes the required baseline inspections and report of results for the replacement steam dryer. Grand Gulf's proposed long term steam dryer inspection plan will be submitted in a separate report.

References

1. Grand Gulf Nuclear Station, Unit 1- Issuance of Amendment RE: Extended Power Uprate (TAC No. ME4679), Nuclear Regulatory Correspondence ML121210020, July 18, 2012.

2. BWRVIP-139-A BWR Vessel and Internals Project, Steam Dryer Inspection and Flaw Evaluation Guidelines, 1018794, July 2009.

3. BWRVIP-03 BWR Vessel and Internals Project, Reactor Pressure Vessel and Internals Examination Guidelines, TR-1 05696-R 19, December 2016.

4. General Electric Service Information Letter (SIL) 644, "BWR Steam Dryer Integrity."

5. Grand Gulf Nuclear Station Recommendations for Future Inspection- Replacement Steam Dryer, General Electric Report 0000-0125-6316-R 1, December 2013.

6. In Vessel Visual Inspection (IVVI) of Grand Gulf Nuclear Station during the Spring 2014 Outage (GGNS RF19), GEH-7480-316097-JB1-IVVI, February 2014.

7. In Vessel Visual Inspection (IVVI) of Grand Gulf Nuclear Station during the Spring 2016 Outage (GGNS RF20), GEH-7480-318931-JB1-IVVI, February 2016.