NL-16-1609, Refueling Outage 2R18 Steam Generator Tube Inspection Report

Refueling Outage 2R18 Steam Generator Tube Inspection Report

ML16257A297
Person / Time
Site:	Vogtle
Issue date:	09/13/2016
From:	Wheat J Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NL-16-1609
Download: ML16257A297 (17)

Text

Justin T. Wheat Southern Nuclear Nuclear Licensing Manager Operating Company, Inc.

A Southern Nuclear 40 Inverness Center Parkway Post Office Box 1295 Birmingham, AL 35242 Tel 205.992.5998 Fax 205.992 .7601 SEP 1 3 2016 Docket No.: 50-425 NL-16-1609 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Vogtle Electric Generating Plant, Unit 2 Refueling Outage 2R18 Steam Generator Tube Inspection Report Ladies and Gentlemen:

In accordance with the requirements of Vogtle Electric Generating Plant (VEGP) Technical Specification 5.6.1 0, Southern Nuclear Operating Company submits the enclosed report of the steam generator tube inspections performed during the eighteenth refueling outage on Unit 2 (2R18.)

This letter contains no NRC commitments. If you have any questions, please contact Ken McElroy at 205.992.7369.

Respectfully submitted,

~~

Justin T. Wheat Nuclear Licensing Manager JTW/JMC/Iac

Enclosure:

VEGP 2R 18 Steam Generator Tube Inspection Report cc: Southern Nuclear Operating Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bast, Executive Vice President & Chief Nuclear Officer Mr. D. R. Madison, Vice President- Fleet Operations Mr. M. D. Meier, Vice President- Regulatory Affairs Mr. B. K. Taber, Vice President- Vogtle 1 & 2 Mr. B. J. Adams, Vice President- Engineering Mr. D. D. Sutton, Regulatory Affairs Manager- Vogtle 1 & 2 RType: CVC7000

U.S. Nuclear Regulatory Commission NL-16-1609 Page2 U.S. Nuclear Regulatory Commission Ms. C. Haney, Regional Administrator Mr. R. E. Martin, NRR Senior Project Manager- Vogtle 1 & 2 Ms. N. R. Childs, Senior Resident Inspector- Vogtle 1 & 2

Vogtle Electric Generating Plant - Unit 2 Refueling Outage 2R18 Steam Generator Tube Inspection Report Enclosure VEGP 2R18 Steam Generator Tube Inspection Report

Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report Introduction The Vogtle Electric Generating Plant (VEGP) eighteenth refueling outage on Unit 2 (2R18) was conducted after Steam Generator (SG) service equivalent to 1.37 effective full power years (EFPY) from previous SG eddy current inspections. At VEGP 2R18, approximately 69.0 effective full power months (EFPM) of the 72 EFPM in the fourth sequential inspection period have been accrued making 2R 18 the last inspection of the period. At the conclusion of VEGP 2R 18, all tubes in-service at the beginning of the period have been inspected. No tube leakage was reported during the operating interval. Condition Monitoring (CM) and Operational Assessments (OA) analyses based on conservative assumptions demonstrated that no tubes exceeded Regulatory Guide 1.121 or NEI-97-06 Revision 3 criteria for tube integrity during the cycle.

The Westinghouse Nuclear Services Division Steam Generator Maintenance Services Group performed eddy current inspections. NDE Technology performed secondary data analysis under direct contract with Southern Nuclear Operating Company (SNC). During VEGP 2R18, no tubes were plugged in any SG. None of the indications exceeded the CM limits identified in the Degradation Assessment and therefore did not require in situ pressure testing. Permanent H* Alternate Repair Criteria (ARC) have been approved for implementation by the NRC.

Therefore, SNC and Westinghouse omitted tube end +Point' inspections below top of tubesheet (ITS) -15.2 inches. ITS inspections ranged from ITS +3 inches to ITS -15.2 inches. The scope of inspections on each SG, and the results of those inspections are described below.

Vogtle 2R18 SG Scope The 2R18 scope involved the scheduled inspections listed below. In accordance with the EPRI PWR SG Examination Guidelines, Revision 7, the 2R18 inspection program addressed VEGP 2 degradation mechanisms observed from prior inspections as well as those regarded as potential degradation mechanisms. In-service inspection (lSI) examination used Bobbin and Rotating Pancake Coil (RPC) +Point' Eddy Current Testing (ECT) inspection methods.

• 100% full length Bobbin examination of tubes in all four SGs, except for Rows 1 and 2.

Row 1 and 2 were inspected with Bobbin from tube end to the top tube support plate (TSP) from both hot leg (HL) and cold leg (CL).

• 50% +Point' probe examination of Row 1 and Row 2 U-bends in all four SGs from the top TSP on the HL to the top TSP on the CL

• +Point' probe Special Interest (possible flaw locations with bobbin coil probe) including U-bends in both the HL and CL in all four SGs

• 100% +Point' probe examination ofTSP intersections in the HL and CL of high residual stress tubes identified in the degradation assessment, in all four SGs.

• 100% +PointTM probe examination of HL tubes in SG2 and 50% in SG1, SG3 and SG4 from the ITS to the licensed ARC depth for H* (Tubesheet Region on HL side (TSH)

+3/-15.2 inches). This inspection satisfied the required periodic sample that accompanies regulatory approval of the H* ARC.

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Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report

• +Point' probe examination of HL and CL periphery and tubelane tubes, excluding tubelane Columns 12 through 111, three tubes deep from ITS +3/-15.2 inches on the HL side and ITS +3/-3inches on the CL side in all SGs.

• 50% of the HL tube bulge (BLG)/ overexpansion (OXP) populations in all four SGs. This scope was captured as part of the HL tubesheet inspection scope. The BLG and OXP indications were defined as follows:

o BLG = differential mix diameter discontinuity signal within the tubesheet of 18 volts or greater as measured by bobbin coil probe.

o OXP =a tube diameter deviation within the tubesheet of 1.5 mils or greater as measured by bobbin coil probe.

• 50% +Point' probe examination of dents and dings<:: 2 volts in HL straight lengths and U-bends of all four SGs. This sample was taken from the total number of dents and dings identified during previous inspections and any additional identified by the bobbin program.

• 100% visual inspection of HL and CL installed tube plugs from the primary side in all four SGs.

• Visual inspection in all SGs of channel head primary side HL and CL inclusive of the entire divider plate to channel head weld and all visible clad surfaces.

Secondary Side activities performed included:

• ITS Sludge Lancing in all 4 SGs.

• Upper Bundle In-Bundle (UBIB) and Top TSP Visual Inspection in SG2

• Foreign Material Search and Retrieval (FOSAR) in all 4 SGs.

FOSAR inspections included:

• Tubesheet annulus and tubelane region including the HL and CL periphery tubes.

• Possible Loose Parts (PLP) from eddy current tube inspections.

• Legacy objects.

Inspection Expansion VEGP 2R18 SG ISis required no non-destructive examination (NDE) inspection scope expansion.

Damage Mechanisms Found and NDE Techniques Utilized All of the damage mechanisms found during 2R18 inspections were identified in previous inspections and in the 2R18 SG Degradation Assessment. Based on SG eddy current and visual inspection data, the existing degradation mechanisms in the VEGP 2 SGs are below.

• Mechanical Wear due to Foreign Objects o +Point' and bobbin techniques were used to evaluate the wear indications E-2

Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report

• Mechanical Wear at Anti-Vibration Bar (AVB) Supports o Bobbin techniques were used to evaluate the wear indications

• Mechanical Wear and Wall Loss from Secondary Side Cleaning Processes o Bobbin and +Point' techniques were used to evaluate the wear indications

• Circumferential Outer Diameter Stress Corrosion Cracking (ODSCC) at Hot Leg Tubesheet Expansion Transitions o +Point' techniques were used to evaluate the ODSCC indications Service Induced Indication Descriptions Mechanical Wear due to Foreign Objects Foreign objects have been reported as the cause for tube wear at VEGP Unit 2 during prior inspections. Therefore, wear due to foreign objects is classified as an existing degradation mechanism and has been addressed in the SG inspections performed during VEGP 2R 18.

Table 1, Possible Loose Part Indications, lists the data record for the eddy current signals corresponding to a PLP. All PLP signals in Table1 have been visually inspected during VEGP 2R 18. The historical PLP indications listed show no significant change in eddy current signal response. Additionally, no new foreign object wear associated with known foreign objects in the SG secondary side was observed. Only sludge and deposits were observed during the visual inspections of SG1 Row 57 Column 59 (R57C59), SG2 R4C58 and SG2 R21 C61, while a benign piece of scale was observed at R52C91 in SG4. Although a majority of the indications in Table 1 are located in SG2, most have been present for several cycles. It is judged that these SGs are no more likely than any of the others to be affected by foreign objects during future operation.

Table 2, Foreign Object Wear Indications, shows the foreign object wear indications (PCT) observed during VEGP 2R18. PCT indications in tubes R47C84 and R47C85 in SG1 have been present for several cycles with no apparent growth or change outside NDE measurement uncertainties. Secondary side visual inspections also show no visual change in indications' character. PCT indications in SG41isted in Table 2, tubes R12C57 and R42C93, show virtually no change in size from prior inspection.

The volumetric wear indication in SG4 at tube R57C68 listed in Table 2 was resolved from a Distorted Support Indication (DSI) to a Distorted Support Signal (DSS) by bobbin data history review in prior inspections. The indication was designated a volumetric flaw during 2R18 based on lead analyst detailed data history review of both bobbin and +Point' probe data.

During VEGP 2R18 the lead analyst performed a side-by-side comparison of the 2R18 and 2R9

+Point' probe data. The comparison showed that the indication has been present and unchanged since at least the 2R9 inspection in 2002 which was the most recent +Point' inspection of this location. A conservative +Point' probe box-in of surrounding tubes was also performed during VEGP 2R 18 and the result was no other degradation or PLPs present. This tube remains in-service and will continue to be monitored as a volumetric indication during future inspections.

Based on the inspection data, 2R18 CM has been met for degradation associated with foreign object wear indications.

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Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report Table 1: VEGP 2R18 Possible Loose Part Indications (PLPs)

SG Row Column Indication Location 1 57 59 PLP TSH+0.12 2 31 49 PLP TSH+1.57 2 32 49 PLP TSH+ 0.83 2 32 49 PLP TSH+1.34 2 32 50 PLP TSH+0.67 2 32 50 PLP TSH+0.57 2 33 50 PLP TSH+0.25 2 4 58 PLP TSH+ 0.32 2 21 61 PLP TSH+0.12 4 52 91 PLP TSC+0.14 Table 2: VEGP 2R18 Foreign Object Wear Indications (PCTs)

SG Row Column Indication %TWD 1 Location 1 47 84 PCT 10 TSH+0.19 1 47 85 PCT 9 TSH+0.14 4 12 57 PCT 21 TSH+0.41 4 57 68 PCT 352 BPC+0.34 4 42 93 PCT 24 TSC+0.84 1

%TWD- tube percent through wall depth measured by a qualified bobbin or +Point' technique.

2

+Point' probe data history review shows this indication has been present and unchanged since at least 2002. This indication has been characterized as a DSS during prior inspections based on bobbin data history review. No associated PLP has been identified from +Point' inspection of surrounding tubes.

TSH - Tubesheet region on HL side TSC -Tubesheet region on CL side BPC - Baffle Plate on CL side Mechanical Wear at Anti-Vibration Bar (AVB) Supports All AVB wear locations have been examined in all four SGs and none of the wear locations exceeded the technical specification plugging limit of 40% through-wall (TW).

The maximum AVB wear indication reported during VEGP 2R18 was in SG4 at R57C48 AV5 measuring 39% TW. This indication has grown in depth by only 2% TW from the prior inspection during 2R17. This wear indication is also significantly less than the maximum projected depths for AVB wear indications at the end of Cycle 18 which was calculated in the 2R 16 and 2R 17 CMOA. Therefore, the degradation growth projection methods applied in the OA for this mechanism remain both appropriate and conservative.

Based on the inspection data, CM has been met at the VEGP 2R18 inspection for degradation associated with AVB wear indications. None of the indications exceeded the CM limits and E-4

Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report therefore did not require in-situ pressure and leakage testing to demonstrate tube integrity. AVB wear identified is provided in Table 3 (SG1 ), Table 4 (SG2), Table 5 (SG3), and Table 6 (SG4).

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Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report Table 3: VEGP 2R18 SG1 AVB Wear Indications SG Row Column Location 2R18% TWO SG Row Column Location 2R18%TWD 1 29 105 AV2 9 1 47 99 AV5 14 1 29 112 AV2 13 1 48 27 AV1 10 1 30 10 AV2 9 1 48 27 AV2 12 1 30 10 AV6 13 1 48 27 AV3 17 1 32 17 AV5 16 1 48 28 AV2 21 1 32 106 AV5 18 1 48 96 AV2 9 1 34 13 AV2 18 1 49 29 AV6 13 1 34 13 AV4 13 1 49 36 AV2 20 1 34 25 AV1 11 1 49 36 AV5 28 1 35 14 AV4 13 1 50 29 AV5 24 1 35 74 AV4 17 1 50 92 AV2 11 1 37 33 AV3 11 1 50 93 AV3 12 1 37 35 AV3 12 1 53 33 AV4 18 1 41 20 AV1 9 1 53 34 AV3 13 1 41 20 AV2 18 1 53 34 AV4 12 1 41 20 AV3 11 1 53 89 AV5 12 1 41 20 AV4 15 1 54 50 AV2 13 1 41 20 AV5 15 1 54 50 AV3 12 1 41 20 AV6 9 1 54 50 AV4 10 1 41 21 AV3 12 1 55 39 AV2 9 1 41 23 AV5 16 1 55 39 AV3 11 1 41 23 AV6 11 1 55 78 AV1 8 1 41 27 AV5 13 1 55 78 AV6 12 1 42 20 AV2 19 1 55 81 AV2 7 1 43 21 AV3 12 1 57 78 AV5 12 1 43 21 AV4 10 1 58 53 AV1 10 1 43 100 AV2 17 1 58 72 AV1 14 1 43 100 AV3 20 1 58 73 AV1 10 1 43 100 AV4 23 1 58 75 AV6 16 1 43 100 AV5 14 1 59 68 AV1 13 1 44 22 AV4 15 1 44 22 AV6 14 1 44 23 AV2 14 1 44 23 AV3 22 1 44 23 AV4 18 1 44 23 AV5 28 1 44 27 AV2 11 1 44 27 AV3 16 1 44 27 AV5 10 1 44 72 AV6 10 1 44 94 AV5 13 1 46 24 AV4 15 1 46 26 AV4 21 1 46 27 AV2 13 1 46 32 AV3 15 1 46 32 AV4 17 1 46 32 AV5 14 1 46 43 AV2 14 1 46 58 AV5 17 1 47 27 AV2 26 1 47 36 AV1 11 1 47 36 AV3 14 1 47 36 AV4 10 1 47 40 AV2 11 1 47 99 AV2 14 AV#- Location of AVB intersection with the tube {there are up to 6)  % lWD-Percent Through-wall Depth E-6

Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report Table 4: VEGP 2R18 SG2 AVB Wear Indications SG Row Column Location 2R18%TWD SG Row Column Location 2R18%TWD 2 12 121 AV6 9 2 40 73 AV5 14 2 28 115 AV1 12 2 40 73 AV6 10 2 28 115 AV6 21 2 41 104 AV6 11 2 29 10 AV5 12 2 42 19 AV2 11 2 30 10 AV5 10 2 42 19 AV3 13 2 30 109 AV6 11 2 42 19 AV4 12 2 34 12 AV3 8 2 42 19 AV5 11 2 36 14 AV4 5 2 42 50 AV2 13 2 36 16 AV5 12 2 42 50 AV3 9 2 36 16 AV6 12 2 42 50 AV4 10 2 36 106 AV2 12 2 42 74 AV2 31 2 36 106 AV3 10 2 42 74 AV3 28 2 36 106 AV4 13 2 42 74 AV4 11 2 36 106 AV5 12 2 42 74 AV5 10 2 36 106 AV6 11 2 42 74 AV6 7 2 37 54 AV5 13 2 42 88 AV2 9 2 38 15 AV2 9 2 43 20 AV1 10 2 38 15 AV3 12 2 43 20 AV2 13 2 38 39 AV2 8 2 43 40 AV5 10 2 38 39 AV3 14 2 43 64 AV1 15 2 38 39 AV4 10 2 43 73 AV4 22 2 38 39 AV5 17 2 44 72 AV5 19 2 38 45 AV1 6 2 45 49 AV3 8 2 38 74 AV1 10 2 48 56 AV3 10 2 38 74 AV2 16 2 49 32 AV4 11 2 38 74 AV3 18 2 49 66 AV2 17 2 38 74 AV4 19 2 49 66 AV3 16 2 38 74 AV5 11 2 49 74 AV3 21 2 38 74 AV6 8 2 49 91 AV1 10 2 38 81 AV2 10 2 49 91 AV2 24 2 38 81 AV3 8 2 49 91 AV3 14 2 38 81 AV5 12 2 50 70 AV3 13 2 38 81 AV6 15 2 50 70 AV4 19 2 38 100 AV3 14 2 50 89 AV3 8 2 39 43 AV2 21 2 50 89 AV4 12 2 39 43 AV3 20 2 50 89 AV5 8 2 39 43 AV4 13 2 50 89 AV6 11 2 39 43 AV5 14 2 50 91 AV4 6 2 39 43 AV6 8 2 51 71 AV6 8 2 39 44 AV2 11 2 51 72 AV2 13 2 39 44 AV3 18 2 51 72 AV3 12 2 39 44 AV5 11 2 51 72 AV4 10 2 39 44 AV6 9 2 51 72 AV5 11 2 39 52 AV3 10 2 51 74 AV2 12 2 39 52 AV4 15 2 51 74 AV3 23 2 39 88 AV4 13 2 51 74 AV4 11 2 39 107 AV2 8 2 51 74 AV5 9 2 40 48 AV4 21 2 51 74 AV6 9 2 40 48 AV5 12 2 51 87 AV2 31 2 40 52 AV3 21 2 51 87 AV3 30 2 40 52 AV5 8 2 51 87 AV4 21 2 40 54 AV3 12 2 51 87 AV5 30 2 40 57 AV3 10 2 51 89 AV3 12 2 40 63 AV3 13 2 51 89 AV4 30 2 40 64 AV4 11 2 51 89 AV5 28 2 40 73 AV3 12 2 51 89 AV6 14 E-7

Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report SG Row Column Location 2R18%TWD SG Row Column Location 2R18%TWD 2 51 90 AV3 12 2 51 90 AV4 17 2 51 90 AV5 15 2 51 91 AV3 7 2 51 91 AV4 13 2 51 91 AV5 26 2 51 91 AV6 14 2 52 52 AV3 6 2 52 91 AV4 11 2 53 52 AV3 7 2 53 88 AV4 14 2 53 88 AV5 24 2 53 90 AV4 9 2 53 90 AV6 11 2 54 86 AV4 13 2 55 74 AV5 9 2 55 84 AV1 7 2 55 84 AV4 12 2 56 41 AV3 12 2 56 43 AV2 8 2 56 43 AV6 10 2 56 52 AV3 9 2 56 82 AV5 11 2 57 49 AV6 12 2 57 62 AV1 8 2 57 62 AV2 8 2 57 64 AV3 12 2 57 64 AV4 11 2 57 72 AV1 12 2 57 72 AV3 13 2 57 79 AV3 7 2 57 79 AV4 9 2 58 70 AV2 9 2 59 56 AV4 11 2 59 66 AV2 12 AV#- Location of AVB intersection with the tube (there are up to 6)  % lWD-Percent Through-wall Depth E-8

Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report Table 5: VEGP 2R18 SG3 AVB Wear Indications SG Row Column Location 2R18%TWD SG Row Column Location 2R18%TWD 3 12 121 AV1 8 3 52 83 AV2 19 3 30 112 AV5 8 3 52 83 AV3 36 3 32 12 AV2 14 3 52 83 AV4 32 3 32 12 AV5 20 3 52 83 AV5 28 3 34 13 AV1 13 3 53 62 AV3 10 3 34 13 AV2 11 3 53 62 AV5 5 3 34 13 AV4 10 3 54 38 AV3 13 3 34 13 AV5 20 3 54 38 AV5 17 3 34 13 AV6 13 3 54 62 AV2 6 3 34 105 AV2 10 3 57 48 AV4 13 3 35 64 AV4 5 3 57 48 AV5 13 3 39 19 AV4 15 3 57 48 AV6 13 3 39 72 AV2 19 3 57 49 AV4 9 3 39 72 AV3 26 3 57 62 AV4 11 3 39 72 AV4 30 3 57 78 AV2 10 3 40 44 AV2 14 3 58 49 AV1 11 3 41 19 AV4 13 3 58 49 AV5 14 3 41 77 AV2 13 3 58 49 AV6 12 3 41 77 AV3 6 3 41 77 AV4 22 3 41 77 AV5 21 3 41 82 AV2 8 3 41 82 AV3 10 3 41 82 AV4 8 3 42 20 AV3 17 3 42 20 AV4 15 3 42 53 AV2 14 3 42 53 AV4 10 3 42 64 AV1 5 3 42 64 AV2 24 3 42 64 AV3 24 3 42 64 AV4 36 3 42 64 AV5 22 3 43 62 AV4 6 3 43 82 AV2 12 3 43 82 AV5 18 3 44 23 AV3 12 3 44 64 AV4 5 3 44 68 AV3 6 3 45 62 AV4 6 3 46 36 AV4 16 3 46 62 AV4 9 3 48 37 AV3 15 3 50 29 AV4 12 3 50 48 AV4 11 3 50 48 AV5 15 3 50 48 AV6 10 3 50 95 AV5 12 3 51 38 AV5 10 1  % lWD-Percent Through-wall Depth AV#- Location of AVB intersection with the tube (there are up to 6)

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Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report Table 6: VEGP 2R18 SG4 AVB Wear Indications SG Row Column Location 2R18%TWD SG Row Column Location 2R18%TWD 4 15 36 AV6 9 4 44 42 AV3 15 4 15 46 AV1 9 4 44 42 AV4 19 4 27 79 AV5 9 4 44 42 AV5 25 4 29 14 AV6 8 4 44 42 AV6 16 4 30 9 AV5 20 4 44 44 AV3 19 4 31 10 AV5 15 4 44 53 AV3 12 4 32 109 AV6 8 4 44 53 AV5 11 4 34 81 AV1 7 4 44 54 AV1 13 4 35 81 AV1 7 4 44 54 AV2 20 4 36 14 AV2 10 4 44 54 AV4 11 4 37 74 AV3 12 4 44 54 AV5 29 4 37 79 AV1 9 4 44 59 AV1 12 4 37 81 AV1 8 4 44 59 AV3 16 4 37 87 AV2 11 4 44 59 AV4 12 4 38 39 AV4 10 4 44 85 AV3 9 4 38 79 AV1 7 4 45 22 AV2 8 4 38 81 AV1 7 4 45 22 AV3 10 4 39 26 AV3 8 4 45 23 AV2 7 4 39 64 AV1 18 4 45 23 AV3 6 4 39 64 AV2 26 4 45 23 AV5 8 4 39 64 AV3 33 4 45 32 AV3 23 4 39 64 AV4 17 4 45 32 AV4 12 4 39 64 AV5 15 4 45 42 AV3 12 4 39 64 AV6 25 4 45 42 AV4 32 4 40 79 AV1 8 4 45 42 AV5 14 4 40 106 AV1 9 4 45 58 AV3 30 4 40 106 AV3 8 4 45 58 AV4 12 4 42 51 AV6 8 4 45 58 AV5 19 4 42 87 AV3 9 4 45 66 AV2 19 4 43 21 AV3 11 4 45 66 AV3 19 4 43 21 AV4 14 4 45 66 AV5 22 4 43 21 AV5 10 4 46 26 AV4 13 4 43 21 AV6 12 4 46 26 AV6 13 4 43 22 AV4 14 4 46 31 AV2 9 4 43 35 AV2 13 4 46 31 AV3 26 4 43 36 AV2 15 4 46 31 AV4 15 4 43 47 AV2 10 4 46 31 AV5 18 4 43 51 AV6 9 4 46 51 AV6 9 4 43 53 AV3 8 4 46 88 AV3 10 4 43 58 AV4 11 4 47 33 AV5 12 4 43 58 AV5 10 4 47 36 AV4 11 4 43 65 AV4 13 4 47 36 AV6 13 4 43 68 AV3 21 4 47 41 AV2 14 4 43 68 AV4 25 4 47 41 AV3 12 4 43 68 AV5 24 4 48 31 AV3 7 4 43 69 AV5 18 4 48 31 AV4 11 4 43 71 AV4 14 4 48 57 AV3 10 4 43 76 AV5 19 4 48 57 AV4 11 4 43 85 AV4 12 4 48 57 AV5 16 4 43 95 AV3 19 4 48 58 AV4 9 4 43 95 AV4 15 4 48 79 AV2 10 4 43 95 AV5 14 4 48 79 AV3 8 4 44 29 AV3 16 4 48 81 AV1 9 4 44 29 AV4 16 4 48 97 AV2 11 4 44 29 AV5 10 4 48 97 AV3 13 4 44 42 AV2 11 4 49 53 AV3 9 E -10

Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report SG Row Column Location 2R18%TWD SG Row Column Location 2R18%TWD 4 49 53 AV4 10 4 53 74 AV5 10 4 49 58 AV4 11 4 53 80 AV4 11 4 49 83 AV3 14 4 53 80 AV5 15 4 49 93 AV4 19 4 53 89 AV5 12 4 49 93 AV5 24 4 53 89 AV6 11 4 49 96 AV2 13 4 54 35 AV4 9 4 50 53 AV3 8 4 54 35 AV5 19 4 50 55 AV3 8 4 54 35 AV6 9 4 50 70 AV3 20 4 54 37 AV1 9 4 51 31 AV4 11 4 54 37 AV6 9 4 51 35 AV4 17 4 54 83 AV5 10 4 51 37 AV4 10 4 55 41 AV5 13 4 51 39 AV2 12 4 55 83 AV5 11 4 51 39 AV3 13 4 56 42 AV5 9 4 51 39 AV4 18 4 56 42 AV6 9 4 51 43 AV3 11 4 56 45 AV4 15 4 51 43 AV4 13 4 56 45 AV5 10 4 51 43 AV5 12 4 56 47 AV3 20 4 51 54 AV3 14 4 56 76 AV5 10 4 51 54 AV4 23 4 56 82 AV2 13 4 51 54 AV5 13 4 56 82 AV6 11 4 51 55 AV2 13 4 57 48 AV2 19 4 51 55 AV3 19 4 57 48 AV3 23 4 51 55 AV5 11 4 57 48 AV4 17 4 51 60 AV3 15 4 57 48 AV5 39 4 51 65 AV4 19 4 57 48 AV6 14 4 51 65 AV5 28 4 57 71 AV6 12 4 51 76 AV2 16 4 57 73 AV2 14 4 51 76 AV4 18 4 57 76 AV5 14 4 51 76 AV5 23 4 57 78 AV2 13 4 51 92 AV1 14 4 57 78 AV4 11 4 52 33 AV2 17 4 57 78 AV6 13 4 52 33 AV3 17 4 58 47 AV5 15 4 52 33 AV4 16 4 58 47 AV6 12 4 52 33 AV5 38 4 58 75 AV2 11 4 52 33 AV6 14 4 59 63 AV6 9 4 52 45 AV2 12 4 59 66 AV6 14 4 52 45 AV3 21 4 52 45 AV4 19 4 52 45 AV5 12 4 52 66 AV1 13 4 52 66 AV2 22 4 52 66 AV3 14 4 52 71 AV1 10 4 52 71 AV2 22 4 52 71 AV3 24 4 52 72 AV2 33 4 52 72 AV3 16 4 52 78 AV4 13 4 52 85 AV1 8 4 53 34 AV2 10 4 53 34 AV6 10 4 53 36 AV4 10 4 53 36 AV5 13 4 53 36 AV6 11 4 53 44 AV3 16 4 53 74 AV4 17 AV#- Location of AVB intersection with the tube (there are up to 6)  % TWO-Percent Through-wall Depth E- 11

Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report Mechanical Wear and Wall Loss from Secondary Side Cleaning Processes The tube locations and volumetric indications associated with the ultrasonic energy cleaning (UEC) and pressure pulse cleaning (PPC) secondary side cleaning processes are listed in Table 7. The bobbin inspection program examinations address this existing degradation mechanism. VEGP 2R18 performed 100% bobbin inspection of all four SGs.

Prior outages also observed volumetric indications in Row 1 tubes by visual inspection. They have been reported to visually resemble tube oxide removal patterns observed in UEC qualification testing. No foreign objects have been determined to be associated with these tube wear indications. These tubes have been left in service for several inspection intervals with no indications of tube wall loss outside nondestructive examination (NDE) measurement uncertainties. Based on +Point' probe data and history, the SG1 indication at tube R1C78 approximately 11 inches above the top of the tubesheet on the cold leg side has been segregated into two separate volumetric indications. Prior inspections identified it as one indication. This change simply improves degradation tracking. +Point' probe data graphics for these indications show no change from prior inspections back as far as 2008.

Based on the inspection data presented in Table 7 in comparison to the limits, CM has been met for degradation associated with indications of wear and wall loss from secondary side cleaning processes at the 2R 18 inspection.

Table 7: VEGP 2R18 Tube Wall Loss from Secondary Cleaning Process SG Row Column Volts Indication %TWO Location 1 1 42 0.10 PCT 10 TSH+10.96 1 1 45 0.13 PCT 12 TSH+11.06 1 1 46 0.26 PCT 22 TSH+11.11 1 1 78 0.21 PCT 18 TSH+9.99 1 1 78 0.13 PCT 12 TSH+11.77 1 1 78 0.16 PCT 14 TSC+11 .78 1 1 78 0.39 PCT 29 TSC+11.94 3 1 112 0.29 PCT 24 TSC+18.18

%TWO - Percent Through-wall Depth PCT - Volumetric Indication TSC - Tubesheet Region on the CL side TSH - Tubesheet Region on the HL side OOSCC at the Hot Leg Expansion Transitions Outside Diameter Stress Corrosion Cracking (ODSCC) at the hot leg expansion transitions is an existing degradation mechanism for VEGP 2. VEGP 2R 18 eddy current inspection scope development considered this mechanism in accordance with guidelines. There were no ODSCC indications reported at or near the top of the tubesheet hot leg expansion transitions from

+Point' probe inspection during VEGP 2R18. Therefore, the CM requirements relative to structural and leakage integrity have been met for degradation associated with ODSCC at the hot leg expansion transitions.

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Enclosure to NL-16-1609 VEGP 2R18 Steam Generator Tube Inspection Report Number of Tubes Plugged There were no tubes plugged in any of the four SGs during the VEGP 2R18 outage. A 100%

visual inspection of installed tube plugs in all four SGs was performed from the primary side during VEGP 2R18. There were no anomalous conditions, such as a degraded tube plugs or surrounding boron deposits, reported during performance of the visual inspections. All tubes were present and in the proper locations. Cumulative SG tube plugging percentages following VEGP 2R18 are presented below.

Table 8: Total Plugged Tubes after VEGP 2R18 VEGP 2R18 Total#

SG #Tubes #Plugged Plugged %Plugging 1 5,626 0 6 0.11%

2 5,626 0 15 0.27%

3 5,626 0 5 0.09%

4 5,626 0 22 0.39%

Total 22,504 0 48 0.21%

Tube Slippage Monitoring and Leakage Considerations The bobbin data collected from all four SGs has been screened for large amplitude tubesheet indications of greater than 50 volts with a phase angle between 25° and 50° suggestive of tube severance. No tube severance indications were reported; therefore, no indications of slippage were identified.

None of the indications reported during the VEGP 2R 18 SG inspections are evaluated to have primary to secondary leakage as accident induced conditions. There was no leakage from the portion of tubing within the H* depth for which to apply the leak rate factor associated with the ARC. There was no calculated leakage from any other sources and none of the tube plugs installed in the VEGP 2 SGs require considerations for leakage. Therefore, the accident induced leakage rate for these indications would be zero, and the accident induced leakage performance criterion is satisfied.

Other Inspections SG Channel Head Primary Side Bowl Inspections During VEGP 2R 18, a visual inspection of the SG channel head bowl of the SG hot leg and cold leg divider plate and drain line areas, inclusive of the entire divider plate to channel head weld and all visible clad surfaces, was performed in accordance with Westinghouse NSAL-12-1 and industry operating experience. This inspection was performed using the SG manway channel head bowl cameras. No channel head degradation was observed in any SGs.

Secondary Side Activities Discussion During VEGP 2R18, TIS deposit cleaning sludge lancing was performed in all four SGs. A total of 24.5 pounds of sludge was removed from all four SGs. Foreign object search and retrieval (FOSAR) inspections were conducted in the secondary side of all four SGs during VEGP 2R 18.

These FOSAR inspections were performed at the TIS region around the annulus as well as the E -13

Enclosure to NL-16-1609 VEGP 2R 18 Steam Generator Tube Inspection Report no-tube lane through the center of the tube bundle. The FOSAR scope also included known foreign object locations from prior inspections. Secondary side visual inspections were also conducted at locations of historical PLP indications and any new PLP indications identified by the eddy current program. An upper bundle in-bundle (UBI B) inspection and a remote camera inspection of the top tube support plate (TSP7) were performed in SG2 during VEGP 2R18. The tube freespans and the tops of the tube support plates viewed were largely free from significant deposit buildup.

Condition Monitoring Conclusions Based on the inspection data and the CM assessment, no tubes exhibited degradation in excess of the CM limits. No tubes required in situ pressure testing to demonstrate structural and leakage integrity. There was no reported SG primary to secondary leakage prior to the end of the VEGP 2 SG inspection interval. No new indications of secondary side tube degradation attributable to foreign objects have been identified and all PLPs have been visually inspected from the secondary side. The SG performance criteria for operating leakage and structural integrity were satisfied for the preceding VEGP Unit 2 SG inspection interval for all four SGs.

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