ML24142A095
| ML24142A095 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 05/20/2024 |
| From: | O'Connor M Dominion Energy Nuclear Connecticut |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| 24-154 | |
| Download: ML24142A095 (1) | |
Text
Dominion Energy Nuclear Connecticut, Inc.
Millstone Power Station 314 Rope Ferry Road, Waterford, CT 06385 Dominion Energy.com U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 MAY 2 0 2024 DOMINION ENERGY NUCLEAR CONNECTICUT, INC.
MILLSTONE POWER STATION UNIT 3
~
Dominion
~
Energy Serial No.
NSSL/TFO Docket No.
License No.24-154 RO 50-423 NPF-49 END OF CYCLE 22 STEAM GENERATOR TUBE INSPECTION REPORT In accordance with the Millstone Power Station Unit 3 Technical Specification (TS)
Section 6.9.1.7, Dominion Energy Nuclear Connecticut, Inc. hereby submits the End of Cycle 22 (EOC22) Steam Generator (SG) Tube Inspection report.
The report is submitted within 180 days after initial entry into MODE 4 following completion of the fall 2023 SG inspections performed in accordance with TS 6.8.4.g, "Steam Generator (SG)
Program." Initial entry into Mode 4 occurred on November 26, 2023. contains the EOC22 SG Tube Inspection report. Attachment 2 contains a list of acronyms.
The report addresses the following reporting requirements:
- a. The scope of inspections performed on each SG,
- b. Degradation mechanisms found,
- c. Nondestructive examination techniques utilized for each degradation mechanism,
- d. Location, orientation (if linear), and measured sizes (if available) of service induced indications,
- e. Number of tubes plugged during the inspection outage for each degradation mechanism,
- f.
The number and percentage of tubes plugged to date and the effective plugging percentage in each steam generator,
- g. The results of condition monitoring, including the results of tube pulls and in-situ
- testing,
- h. The primary to secondary LEAKAGE rate observed in each SG (if it is not practical to assign the LEAKAGE to an individual SG, the entire primary to secondary LEAKAGE should be conservatively assumed to be from one SG) during the cycle preceding the inspection which is the subject of the report,
- i.. The calculated accident induced leakage rate from the portion of the tubes below 15.2 inches from the top of the tubesheet for the most limiting accident in the most limiting SG. In addition, if the calculated accident induced leakage rate from the most limiting accident is less than 2.49 times the maximum operational primary to secondary leakage rate, the report should describe how it was determined; and
- j.
The results of monitoring for tube axial displacement (slippage).
If slippage is discovered, the implications of the discovery and corrective action shall be provided.
Serial No.24-154 Docket No. 50-423 Page 2 of 2 If you have any questions or require additional information, please contact Mr.
Dean E. Rowe at (860) 444-5292.
Sincerely, Michael J. O'Connor Site Vice President - Millstone Attachments:
- 1) Millstone Power Station Unit 3, End of Cycle 22 Steam Generator Tube Inspection Report
- 2) Acronyms Commitments made in this letter: None cc:
U. S. Nuclear Regulatory Commission Region I 475 Allendale Road, Suite 102 King of Prussia, PA 19406-1415 R. V. Guzman Senior Project Manager - Millstone Power Station U. S. Nuclear Regulatory Commission One White Flint North, Mail Stop 08-C 2 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station Millstone Power Station Unit 3 Serial No.24-154 Docket No.
50-423 End of Cycle 22 Steam Generator Tube Inspection Report MILLSTONE POWER STATION UNIT 3 DOMINION ENERGY NUCLEAR CONNECTICUT, INC. (DENG)
Serial No.24-154 Docket No.
50-423,
Page 1 of 31 End of Cycle 22 Steam Generator Tube Inspection Report Transmittal of this report satisfies Millstone Power Station Unit 3 (MPS3) Technical Specification (TS) 6.9.1.7 which specifies that a report shall be submitted within 180 days after the initial entry into MODE 4 following completion of an inspection performed in accordance with TS 6.8.4.g, Steam Generator (SG) Program.
During MPS3's fall 2023 refueling outage (3R22), steam generator inspections were completed in accordance with TS 6.8.4.g. Initial entry into Mode 4 occurred on November 26, 2023; therefore, this report is required to be submitted to the NRC by May 24, 2024.
This attachment provides a summary of the MPS3 SG inspection results and specific responses to each of the TS 6.9.1.7 reporting requirements. Attachment 2 contains a list of acronyms.
Introduction MPS3 is a four loop Westinghouse pressurized water reactor with Westinghouse Model F SGs. Each SG was fabricated with 5626 U-bend thermally treated lnconel 600 tubes. The tubing is nominally 0.688 inches outside diameter with a 0.040-inch nominal wall thickness.
During SG fabrication, the tubes were hydraulically expanded over the full depth of the 21.23-inch thick tubesheet. The tubesheet was drilled on a square pitch with 0.98 inch spacing. There are 59 rows and 122 columns in each SG. The radius of row 1 U-bends is 2.20 inches. U-bends in rows 1 through 10 were stress relieved after being formed.
The secondary side tube support structures include eight 405 stainless steel support plates and six upper support bars (anti-vibration bars) made of chrome plated lnconel 600. The first or lower support plate is a partial plate with drilled tube holes, commonly referred to as a flow distribution baffle. Figure 9 contains a schematic depicting the general arrangement of the steam generator support configuration without dimensions.
All four MPS3 SGs were last inspected during the End of Cycle (EOC) 21 refueling outage (April 2022) and had operated for approximately 346.1 Effective Full Power Months (EFPM) prior to that outage.
Over cycle 22, the SGs operated for an additional 15.35 EFPM.
Therefore, at the time of this inspection (EOC22), the Unit 3 SGs have accrued approximately 361.4 EFPM of operation as of the End of Cycle (EOC) 22 (October 2023).
The MPS3 SGs operate with a hot-leg temperature of 617°F and have experienced no detectable primary to secondary leakage.
Each of the MPS Unit 3 SGs was screened to identify any low row indications of improper heat treatment.
None were identified.
All four SGs were also screened for long row indications of improper heat treatment (-2 sigma tubes) and associated high residual stress.
This evaluation identified 67, 30, 39, and 23 tubes in SGs A, B, C and D, respectively, which may have been improperly heat treated. These tubes were examined full length with array probes (in addition to the full-length bobbin probe) and closely scrutinized during the analysis process.
Serial No.24-154 Docket No.
50-423,
Page 2 of 31 There were no deviations taken from Mandatory and/or Needed (Shall) requirements important to tube integrity from the EPRI Guidelines referenced by NEI 97-06 during the examination or the cycles preceding the EOC22 examination.
TS 6.9.1. 7 Reporting Requirements This section provides responses to each of the reporting requirements specified in MPS3 TS 6.9.1.7.
Bold wording represents TS verbiage.
The required information is provided immediately following the restatement of each reporting requirement.
A report shall be submitted within 180 days after the initial entry into MODE 4 following completion of an inspection performed in accordance with TS 6.8.4.g, Steam Generator (SG) Program. The report shall include:
- a. The scope of inspections performed on each SG, One hundred percent of the operational tubes in all four SGs were inspected full length using eddy current examination techniques.
The majority of the tubing length was examined with bobbin probes. The U-bends of rows 1 and 2 (955 in-service tubes) were examined with a +Point' probe technique in addition to the bobbin probe examination of the straight legs of the tubes. An additional augmented sample of 1,746 tube locations was examined with a +Point' probe. The augmented sample inspections were performed in areas of special interest including hot leg expansion transitions, tube overexpansion locations, dents/dings, as well as locations where the bobbin probe response was ambiguous.
As a result of concerns for possible degradation at dent/ding locations, the special interest scope of dents/dings with a +Point' probe was increased significantly prior to EOC21 and repeated during the EOC22 examination. The specific dent/ding scope performed during the EOC22 inspection included 100% of all dents/dings ~ 2 Volts located in the hot leg straight section and 100% of all dents/dings ~ 5 Volts in the U-bend and cold-leg sections of the tubes.
It should be noted that both terms Dent and Ding refer to a plastic deformation of the tube that results in a reduction in the tube diameter. The two different terms were used to differentiate between the location of the signals. Historically (early generation designs) the term dent referred to local tube diameter reductions due to corrosion products from carbon steel (typically, drilled carbon steel tube support plates).
The term ding referred to local tube diameter reductions due to mechanical means (manufacturing, vibration, incidents during maintenance activities, or impact from foreign objects).
Since the eddy current signals from both dents and dings are similar, the location of the indication was used to differentiate which term was used (dent for indications at supports and ding for all free span indications).
At MPS Unit 3, the referenced dent signals do not represent the same phenomena as classical denting on older generation units caused by drilled carbon steel support plate
Serial No.24-154 Docket No.
50-423,
Page 3 of 31 corrosion damage. Since the MPS Unit 3 are not similar in design (i.e., quatrefoil stainless steel tube support plate design vs. drilled hole carbon steel tube support plate design) these same "denting" issues do not directly apply to the MPS Unit 3. Tube support plate areas are not susceptible to denting caused by corrosion of the tube support plates.
However, the historical nomenclature assigned to these signals has existed in the database since the steam generators were installed and has remained unchanged since that time.
No scope expansions were required; however, the base scope was augmented with additional rotating probe (including magnetically bias probes) to resolve ambiguous indications consistent with the special interest criteria.
An additional augmented sample of 25,344 tube locations was inspected with an array coil probe.
The array coil probe sample included full length examinations of the previously mentioned tubes with potentially high residual stress (159), and 40 tubes (10 in each SG) in strategically located positions that also provide an assessment of deposit loading and potential clogging/blockage of the broached openings at tube support intersections.
In addition to the 199 tube full length inspections, 100% of the remaining hot leg top-of-tubesheet (TTS) locations (22,112 tubes), and approximately 13% of the cold leg TTS locations (3,033 tubes) were examined with array probes.
The extent of the TTS examinations was from the first support structure detected above the secondary face of the tubesheet to 15.2 inches below the secondary face of the tubesheet.
A License Amendment Request (LAR) to implement a Permanent Alternate Repair Criteria (PARC) for tube degradation near the tube end was approved for use prior to the 3R15 outage. The PARC excludes the lower portion of the tubes (more than 15.2 inches below the top of the tubesheet on both the hot and cold leg sides) from augmented inspection (i.e.,
array or rotating probe) requirements. Furthermore, tubes with degradation (other than tube slippage) more than 15.2 inches below the top of the tubesheet do not require plugging.
Thus, that portion of the tube adjacent to the tube ends, (where linear indications were identified during 3R12), was not required to be inspected with array or +Point' probes during 3R22.
During 3R22, each primary channel head in all four SGs was visually examined prior to the installation of eddy current probe manipulators. This examination revealed no evidence of degradation, no evidence of plug leakage, and no foreign objects. The proper tube number, plug type, and plug position were verified for all previously installed plugs.
Westinghouse issued a Nuclear Safety Advisory Letter, NSAL-12-1 regarding SG channel head degradation. The recommended action is to perform a visual scan of both hot and cold legs of the inside surface of the channel head. Key areas of inspection include the channel head cladding, the divider plate-to-channel head weld and the visible portion of the weld at the top of the channel head bowl drain tube. The purpose of the inspection is to detect any gross defects such as indications in welds, missing weld filler material, a breach of the weld metal, unusual discoloration of the weld metal, dings or gouges, etc.
Serial No.24-154 Docket No.
50-423,
Page 4 of 31 A video camera visual examination in accordance with the requirements of NSAL-12-1 was conducted on all four SGs during 3R22.
The examination identified no evidence of degradation.
During 3R22, secondary side activities were performed in SGs A, B, C, and D and included the following:
SG A
A A
- High pressure sludge lancing removed a total of 41 lbs.
The quantities of sludge removed in each SG is as follows: SG-A (12 lbs.), SG-8 (8 lbs.), SG-C (13 lbs.), and SG-D (8 lbs.).
- Post-sludge lancing visual examination of the TTS annulus and no-tube lane to assess as-left material condition and cleanliness, and to identify and remove any retrievable foreign objects.
- Visual investigation of accessible locations having eddy current indications potentially related to foreign objects, and if present, removal of those retrievable foreign objects.
o Five foreign objects were removed individually from the SGs (see Table 1 ).
o An abundance of objects was also removed by sludge lancing. These objects include scale, small pieces of Flexitallic gasket, and hard deposits.
o Five locations of newly detected wear attributed to foreign objects were observed during 3R22.
o One lodged legacy foreign object was visually confirmed and left in place.
Table 1: 3R22 Foreign Object Tracking FOTS Item Location Description 3R22 Action 3R22 Results Array PLP reported Perform FOSAR at the Legacy PLP on tube 56-44 @OlC was INR R56-C44 during 3R21 located affected tube locations and with Array. However, bounding tube 57-44 15 above and outside of perform ECT on affected/
had a PLP. FOSAR at 57-44 removed a 4" broached opening. No machine turning. Post removal +Point 01C +0.61" wear on affected or bounding tubes to check for confirmed part was removed and no wear bounding tubes.
wear and PLPs.
was present.
FOSAR removed a ~1.5" long metallic strip during the post lance inspection. Array on R51-C68 Irregular Metallic Object Perform FOSAR at the the affected tubes (51-68, 51-69) was NDD.
R51-C69 identified and removed affected tube locations and Yet Array inspection on the bounding tubes 17 from periphery during perform ECT on affected /
detected wear on tube 53-66. Subsequent 2-TSC +0.25" the 3R22 post lance bounding tubes to check for tube bounding on tube 53-66 detected wear examination.
wear and PLPs.
on three more tubes (53-65, 54-65, 54-66).
All bounding tube results associated with tubes (53-65, 54-65, 54-66) were NDD.
Metallic object identified Perform FOSAR at the and removed during the affected tube locations and Object was removed during FOSAR. No PLPs 19 Annulus, 3R22 post lance perform ECT on affected /
or wear detected during 100% H/L TTS TSH +0.00 examination. Object was bounding tubes to check for examination located near the H/L lancing suction foot.
wear and PLPs.
SG A
A B
B C
C D
D Serial No.24-154 Docket No.
50-423,
Page 5 of 31 FOTS Item Location Description 3R22 Action 3R22 Results R58-C53 Flex gasket material Perform FOSAR at the R58-C54 identified and removed affected tube locations and FOSAR removed part from the SG. TTS H/L 20 during the 3R22 post perform ECT on affected /
array did not detect PLP or wear on affected TSH +0.00" lance periphery bounding tubes to check for or bounding tubes.
examination wear and PLPs.
Lancing Strainer Parts Small sludge related pieces. A few small 22 TTS N/A pieces of flexitallic gasket and metallic during 3R22 fragments.
13 TTS Lancing Strainer Parts N/A Small sludge related pieces. A few small during 3R22 pieces of flexitallic gasket.
R45-C99 Foreign object wear Perform 2-tube bounding of Array was NDD (no wear or PLPs) 14 reported in 3R22. No wear indication. FOSAR not on bounding tubes. No loose part detected on 06H-0.94 ECT signal of foreign able to reach the location affected tube.
object.
Metal block previously Inspect affected and R1-C4 bounding tubes with ECT to R1-C5 wedged between check for movement of object Array was NOD (no wear) on bounding tubes.
1 blowdown pipe and and/ or active wear. Visually Legacy wear (R1-C5) had not changed.
TSC +3" tube. Caused wear on inspect to reconfirm location Part configuration was confirmed to be fixed.
two tubes and fixity of object.
7 TTS Lancing Strainer Parts at N/A Small sludge related pieces. A few small 3R22 pieces of flexitallic gasket.
Metallic object identified Perform FOSAR at the During 3R22 post lance FOSAR, metallic R58-C52 affected tube locations and object found next to tube 58-52. Array on 24 and removed during the perform ECT on affected /
affected and bounding tubes was NDD (no TSC +0.00 3R22 post lance bounding tubes to check for wear or PLPs). Item was removed from SG examination wear and PLPs.
and is considered closed out at 3R22.
Multiple pieces of small sludge related 27 TTS Lancing Strainer Parts at N/A material. Multiple pieces of flexitallic gasket 3R22 and banding material ranging from ~0.75" to
~2.5" long.
- During 3R21 (spring 2022), visual inspections of the feed ring, J-nozzles, and feedring supports were completed in all four SGs. In addition to the visual examinations during 3R21, specific components associated with the feedring (tees, reducers, elbows, piping, etc.) in SGs B and D were ultrasonically (UT) examined. The UT inspection results revealed no signs of significant wall loss or degradation.
Therefore, no components in any of the SG steam drums were inspected during 3R22.
The results of all secondary-side visual examinations performed during 3R22 were satisfactory, with no degradation detected and no foreign objects with the potential to challenge tube integrity are known to remain in any of the SGs.
- b. Degradation mechanisms found, The existing degradation mechanisms found during 3R22 included AVB wear, TSP wear, non-support structure volumetric degradation (legacy/ new foreign object wear where the object has been removed, fabrication and maintenance related wear). No corrosion-related degradation, located above the H* distance, was detected in any of the MP3 steam generators during 3R22.
Serial No.24-154 Docket No.
50-423,
Page 6 of 31
- c. Nondestructive examination techniques utilized for each degradation mechanism, Table 2 identifies the examination techniques used for each identified degradation mechanism.
Table 2: Examination Techniques for Degradation Mechanisms Detected De radation Mechanism Techni ue Used AVB Wear Bobbin Detection and Sizin To -of-Tubesheet ODSCC Arra /+Point Detection and +Point Sizin
- d. Location, orientation (if linear), and measured sizes (if available) of service induced indications, A total of 93 Non-AVB Volumetric Wear indications were recorded during the examination, with 66 of those recording wall losses of< 20%. All 93 indications that recorded Non-AVB Volumetric Wear are listed in Table 3.
There was a total of 7 48 AVB wear indications reported in all SGs with 614 of those sized at < 20% through wall.
The 7 48 AVB wear indications are listed in Table 4.
Table 3: Summary of Non-A VB Wear Volumetric Degradation Axial Circ Max SG Row Col Volts Location Extent Extent Depth Cause
(%TW)
SGA 2
17 0.16 05H -0.86" 0.26 0.29 13 TSP Wear SGA 2
109 0.22 06C-0.55" 0.26 0.26 17 TSP Wear SGA 3
112 0.28 06C-0.91" 0.26 0.24 21 TSP Wear SGA 6
122 0.04 TSH +4.13" 0.14 0.19 5
Foreign Object Wear SGA 7
3 0.19 TSC +0.02" 0.19 0.34 22 Foreign Object Wear SGA 15 68 0.23 07C -0.74" 0.24 0.29 18 TSP Wear SGA 15 74 0.40 07C -0.60" 0.26 0.31 26 TSP Wear SGA 18 94 0.17 03H -0.36" 0.29 0.38 14 TSP Wear SGA 20 97 0.13 08C-0.86" 0.19 0.29 13 TSP Wear SGA 23 76 0.19 03C +0.26" 0.19 0.22 15 TSP Wear SGA 24 7
0.24 04H +3.67" 0.22 0.29 26 Foreign Object Wear SGA 24 11 0.10 TSH +0.10" 0.19 0.26 14 Foreign Object Wear SGA 28 112 0.41 01H +0.53" 0.38 0.34 37 Foreign Object Wear SGA 29 109 0.12 TSC +0.10" 0.14 0.19 16 Foreign Object Wear
Serial No.24-154 Docket No.
50-423,
Page 7 of 31 Axial Circ Max SG Row Col Volts Location Extent Extent Depth Cause
(%TW) 0.20 01H +0.53" 0.43 0.34 12 Foreign Object Wear SGA 29 110 0.13 TSC +0.12" 0.17 0.24 17 Foreign Object Wear SGA 35 71 0.26 08C-0.96" 0.24 0.29 19 TSP Wear SGA 36 76 0.12 01H +0.50" 0.29 0.29 11 FOB Wear SGA 43 103 0.07 TSC +0.65" 0.17 0.22 10 Foreign Object Wear SGA 45 100 0.16 01 H +0.07" 0.22 0.24 14 FOB Wear SGA 47 24 0.25 01C +0.94" 0.24 0.29 27 Foreign Object Wear 0.18 01C +0.91" 0.19 0.29 21 Foreign Object Wear SGA 47 25 0.27 01C+1.13" 0.22 0.34 28 Foreign Object Wear SGA 53 65 0.13 TSC +0.10" 0.12 0.26 18 Foreign Object Wear SGA 53 66 0.44 TSC +0.05" 0.24 0.31 38 Foreign Object Wear SGA 54 65 0.12 TSC +0.10" 0.14 0.24 16 Foreign Object Wear SGA 54 66 0.18 TSC +0.10" 0.14 0.26 21 Foreign Object Wear SGA 58 47 0.09 TSC +0.58" 0.17 0.29 12 Sled SGA 58 54 0.19 08H -0.89" 0.24 0.31 15 TSP Wear SGA 58 76 0.08 TSC +0.53" 0.22 0.29 11 Sled SGA 59 60 0.21 08H -1.73" 0.24 0.34 24 Foreign Object Wear SG Row Col Volts Location Axial Circ Max Cause Extent Extent Depth SGB 1
37 0.14 03C + 0.46" 0.24 0.36 6
TSP Wear SGB 1
119 0.14 TSC + 3.77" 0.26 0.38 19 Foreign Object Wear 0.09 TSC + 3.82" 0.24 0.34 12 Foreign Object Wear SGB 1
120 0.06 TSC +4.68" 0.24 0.31 10 Foreign Object Wear SGB 1
121 0.10 TSC + 6.58" 0.53 0.34 14 Foreign Object Wear SGB 15 99 0.20 03H - 0.55" 0.26 0.41 9
TSP Wear SGB 16 36 0.14 05H -0.70" 0.22 0.34 13 TSP Wear SGB 22 118 0.10 TSC + 0.77" 0.31 0.31 14 Sled SGB 29 65 0.17 08C- 0.84" 0.24 0.36 7
TSP Wear SGB 29 109 0.14 04H- 0.48" 0.24 0.34 6
TSP Wear SGB 30 52 0.23 05H - 0.67" 0.29 0.36 10 TSP Wear
Serial No.24-154 Docket No.
50-423,
Page 8 of 31 Axial Circ Max SG Row Col Volts Location Extent Extent Depth Cause
(%TW)
SGB 32 30 0.19 06H- 0.94" 0.26 0.34 8
TSP Wear SGB 44 98 0.31 02H+15.70" 0.29 0.31 28 Fabrication SGB 45 99 0.18 06H - 0.94" 0.22 0.34 21 Foreign Object Wear Axial Circ Max SG Row Col Volts Location Extent Extent Depth Cause
(%TW)
SGC 1
5 0.19 TSC +3.19" 0.26 0.29 12 Foreign Object Wear SGC 3
3 0.20 04C+16.30" 0.19 0.29 15 Fabrication SGC 8
61 0.20 TSH +0.60" 0.29 0.31 23 Foreign Object Wear SGC 13 120 0.27 08C-0.72" 0.26 0.29 19 TSP Wear SGC 17 52 0.53 04H -0.38" 0.26 0.29 29 TSP Wear SGC 20 72 0.08 02H +5.52" 0.24 0.24 7
Fabrication SGC 35 78 0.22 08C -0.86" 0.26 0.29 18 TSP Wear SGC 35 97 0.23 05H -0.60" 0.24 0.34 13 TSP Wear SGC 35 110 0.14 06C -1.08" 0.26 0.29 14 TSP Wear SGC 36 13 0.11 TSC +0.55" 0.24 0.29 16 Sled SGC 36 51 0.24 08C -0.74" 0.26 0.38 19 TSP Wear SGC 36 75 0.17 08C-0.77" 0.24 0.29 15 TSP Wear SGC 38 15 0.10 TSC +0.58" 0.22 0.24 15 Sled SGC 44 102 0.08 TSC +0.58" 0.19 0.24 11 Sled SGC 46 34 0.07 TSH +0.38" 0.22 0.24 6
Foreign Object Wear SGC 46 52 0.21 05C -0.29" 0.19 0.29 18 TSP Wear SGC 47 34 0.08 TSH +0.46" 0.22 0.31 12 Foreign Object Wear SGC 47 61 0.16 06C-0.65" 0.14 0.26 11 TSP Wear SGC 48 25 0.06 TSH +0.48" 0.22 0.36 6
Foreign Object Wear SGC 48 88 0.42 07C-0.62" 0.24 0.34 28 TSP Wear SGC 52 77 0.23 TSC +0.07" 0.19 0.31 25 Foreign Object Wear SGC 52 79 0.34 TSC +0.02" 0.22 0.29 33 Foreign Object Wear SGC 54 64 0.19 TSH +0.14" 0.19 0.34 22 Foreign Object Wear SGC 55 68 0.13 TSH +0.67" 0.24 0.34 17 Foreign Object Wear
Serial No.24-154 Docket No.
50-423,
Page 9 of 31 Axial Circ Max SG Row Col Volts Location Extent Extent Depth Cause
(%TW)
SGC 56 41 0.08 TSH +0.53" 0.29 0.29 11 Foreign Object Wear SGC 56 65 0.23 06H+13.25" 0.38 0.26 20 Fabrication SGC 56 69 0.24 TSH +0.14" 0.19 0.34 26 Foreign Object Wear SGC 56 82 0.07 TSC +0.53" 0.19 0.34 10 Sled SGC 57 44 0.07 TSH +0.55" 0.29 0.29 10 Sled 0.13 TSC +0.53" 0.19 0.29 17 Sled SGC 58 48 0.07 TSH +0.55" 0.34 0.38 10 Sled 0.06 TSC +0.50" 0.22 0.34 9
Sled SGC 58 49 0.06 TSH +0.48" 0.29 0.53 9
Sled 0.11 TSC +0.55" 0.19 0.31 15 Sled SGC 58 76 0.11 TSH +0.50" 0.29 0.34 15 Sled SGC 59 55 0.06 TSC+0.48" 0.14 0.24 9
Sled SGC 59 59 0.05 TSC +0.55" 0.19 0.29 8
Sled SGC 59 68 0.07 TSH +0.55" 0.14 0.29 10 Sled Axial Circ Max SG Row Col Volts Location Extent Extent Depth Cause
(%TW)
SGD 17 24 0.81 07C -0.67" 0.32 0.29 38 TSP Wear SGD 24 89 0.14 06C -0.72" 0.24 0.25 11 TSP Wear SGD 27 39 0.22 08C -0.85" 0.27 0.29 16 TSP Wear SGD 35 73 0.45 04H -0.41" 0.24 0.29 30 TSP Wear SGD 46 24 0.14 01H-0.10" 0.22 0.22 14 FOB Wear SGD 46 99 0.21 01H +0.58" 0.29 0.29 24 Foreign Object Wear SGD 52 42 0.19 01H +0.53" 0.24 0.29 22 Foreign Object Wear SGD 52 91 0.34 01H +2.52" 0.29 0.34 33 Foreign Object Wear SGD 58 50 0.06 01C +0.45" 0.16 0.25 10 Foreign Object Wear SGD 58 51 0.20 01C +0.59" 0.21 0.33 23 Foreign Object Wear
Serial No.24-154 Docket No.
50-423,
Page 10 of 31 Table 4: Millstone 3 EOC22 Inspection Summary - AVB Wear Indications SG Row Col
%TW Elev Volts SG Row Col
%TW Elev Volts A
12 121 14 AV6 -0.28 0.34 A
32 111 17 AV5 +0.17 0.56 A
16 81 11 AVl -0.02 0.21 A
33 13 15 AV5 -0.08 0.4 A
16 81 11 AV6 -0.06 0.2 A
33 111 11 AV6 +0.06 0.2 A
18 72 9
AVl +0.07 0.13 A
34 15 10 AV6 -0.02 0.16 A
21 118 10 AV6 +0.56 0.17 A
34 29 10 AV3 +0.09 0.16 A
22 78 10 AVl +0.11 0.18 A
34 29 9
AV6 +0.04 0.14 A
22 78 11 AV2 +0.15 0.2 A
34 41 15 AV3 +0.02 0.41 A
22 78 13 AV5 -0.04 0.29 A
34 41 11 AV4-0.09 0.21 A
22 78 13 AV6 -0.02 0.27 A
34 44 7
AV3 +0.09 0.08 -
A 24 116 13 AV6 +0.04 0.32 A
34 46 18 AV3 +0.07 0.6 A
26 44 14 AV2 +0.13 0.35 A
34 46 17 AV4+0 0.52 A
26 44 13 AV5 +0.11 0.3 A
34 46 28 AV5 +0 1.56 A
26 115 24 AVl -0.52 1.13 A
34 46 30 AV6 +0.23 1.86 A
27 8
13 AVl +0.06 0.29 A
34 48 18 AVl-0.3 0.58 A
27 8
11 AV6 +0.2 0.2 A
34 48 16 AV2 +0.04 0.49 A
27 9
13 AV3 +0.04 0.29 A
34 48 24 AV3 +0.04 1.14 A
27 115 17 AVl -0.26 0.53 A
34 73 10 AVl +0.11 0.18 A
28 36 11 AV5 -0.02 0.22 A
34 73 11 AV2 +0.17 0.2 A
28 113 11 AV5 +0.16 0.23 A
34 73 15 AV3 -0.13 0.44 A
28 115 29 AVl-0.02 1.68 A
34 73 30 AV4 +0.04 1.79 A
29 40 12 AV2 +0.07 0.27 A
34 73 31 AV5 -0.21 1.98 -
A 29 67 8
AVl -0.02 0.1 A
34 73 11 AV6 +0.06 0.21 A
29 67 16 AV2 -0.02 0.46 A
34 85 15 AV5 -0.15 0.42 A
29 67 10 AV5 +0.04 0.18 A
34 91 10 AV2 +0 0.19 A
29 79 12 AV2 +0.13 0.26 A
34 91 9
AV3 +0 0.12 A
29 79 13 AV5 +0.02 0.28 A
34 91 12 AV4-0.17 0.24 -
A 29 114 11 AV2 -0.31 0.23 A
34 96 10 AV4 +0.09 0.19 A
29 114 10 AV5 -0.15 0.19 A
34 97 12 AV3 -0.02 0.27 A
30 9
27 AV5 +0.7 1.47 A
34 98 13 AV4 +0.04 0.31 -
A 30 10 14 AV5 -0.06 0.38 A
34 107 12 AV4-0.04 0.26 A
30 11 11 AV5 +0.07 0.2 A
34 109 22 AV4 +0.02 0.93 A
30 40 12 AV2 -0.09 0.27 A
35 49 10 AV2 +0.04 0.19 A
30 113 22 AV5 +0.28 0.9 A
35 49 17 AV5 -0.28 0.57 A
30 113 9
AV6 +0.02 0.15 A
35 59 10 AVl -0.09 0.17 A
30 114 13 AVl +0.15 0.32 A
35 59 25 AV2 +0.02 1.2 A
31 61 11 AV5 +0 0.22 A
35 59 13 AV3 -0.02 0.28 A
31 109 14 AV2 -0.02 0.37 A
35 59 10 AV4 +0.02 0.18 A
32 111 16 AV4-0.17 0.49 A
35 59 14 AV5 +0.02 0.38
Serial No.24-154 Docket No.
50-423,
Page 11 of 31 SG Row Col
%TW Elev Volts SG Row Col
%TW Elev Volts A
35 59 15 AV6 -0.02 0.41 A
37 90 21 AV3 +0.02 0.84 A
35 60 17 AV3 +0.02 0.52 A
37 90 12 AV4 +0.02 0.27 A
35 60 29 AV4 +0.04 1.65 A
37 90 11 AV5 +0.02 0.21 A
35 60 26 AV5 -0.23 1.33 A
37 91 17 AV3 -0.02 0.51 A
35 60 12 AV6 +0.09 0.25 A
37 91 14 AV4-0.21 0.36 A
35 61 15 AV2 -0.04 0.41 A
37 91 22 AV5 -0.06 0.96 A
35 61 14 AV4 +0.04 0.37 A
37 91 17 AV6 +0 0.53 A
35 65 12 AV2 +0.09 0.25 A
37 92 13 AV5 -0.09 0.3 A
35 65 16 AV3 +0.06 0.47 A
37 99 10 AV3 +0 0.19 A
35 65 17 AV4 +0.04 0.52 A
37 100 14 AV3 -0.09 0.35 A
35 65 18 AV5 -0.02 0.62 A
37 100 12 AV4-0.06 0.25 A
35 71 16 AV3 -0.15 0.44 A
37 100 14 AV5 -0.06 0.37 A
35 71 26 AV4-0.26 1.28 A
37 102 10 AV4 +0.04 0.17 A
35 71 14 AV5 -0.28 0.34 A
37 102 11 AV5 +0 0.23 A
35 71 11 AV6 +0.02 0.2 A
37 106 13 AV2 -0.04 0.32 A
35 77 8
AVl-0.13 0.1 A
37 106 13 AV3 -0.04 0.3 A
35 77 16 AV2 +0.19 0.45 A
37 106 18 AV4 -0.13 0.6 A
35 77 21 AV3 -0.11 0.82 A
37 106 15 AV5 +0.04 0.41 A
35 77 17 AV4 +0.02 0.52 A
38 52 16 AV2 +0.39 0.47 A
35 77 10 AV5 +0.04 0.18 A
38 52 26 AV3 +0.19 1.31 A
35 80 10 AV3 +0.04 0.16 A
38 52 18 AV4 +0.02 0.63 A
35 90 9
AV2 +0.06 0.14 A
38 52 12 AV5 -0.02 0.26 A
35 90 10 AV3 +0.04 0.16 A
38 79 10 AV6 -0.02 0.16 A
35 100 9
AV3 -0.13 0.14 A
38 86 11 AV5 -0.11 0.21 A
35 108 14 AV2 -0.09 0.36 A
38 106 18 AV3 +0.02 0.63 A
35 108 14 AV3 -0.04 0.36 A
38 106 15 AV4-0.09 0.43 A
35 108 17 AV4-0.15 0.54 A
38 106 15 AV5 +0.02 0.42 A
35 108 9
AV6 -0.11 0.14 A
39 51 13 AV3 +0.04 0.29 A
37 34 8
AVl +0.09 0.09 A
39 51 13 AV4+0 0.28 A
37 45 32 AV2 +0.02 2.02 A
39 57 14 AVl +0.24 0.35 A
37 45 24 AV3 +0.17 1.16 A
39 57 27 AV2 -0.02 1.49 A
37 45 18 AV4 +0.06 0.59 A
39 57 20 AV3 -0.11 0.73 A
37 45 16 AV5 -0.06 0.46 A
39 57 22 AV4 +0.04 0.92 A
37 56 14 AV3 +0.04 0.36 A
39 57 9
AV5 +0.2 0.14 A
37 56 18 AV4 +0.04 0.59 A
39 60 22 AV4 +0.06 0.95 A
37 69 20 AV5 -0.02 0.79 A
39 60 13 AV5 -0.17 0.29 A
37 69 22 AV6 -0.04 0.96 A
39 62 10 AV5 +0.09 0.16 A
37 72 17 AV3 +0.09 0.55 A
39 62 11 AV6 +0.15 0.22 A
37 72 10 AV4 +0.06 0.19 A
39 70 8
AV2 +0.04 0.11 A
37 89 9
AV3 +0.09 0.14 A
39 70 16 AV3 +0.02 0.47 A
37 90 12 AV2 +0.04 0.27 A
39 70 11 AV4-0.13 0.2
Serial No.24-154 Docket No.
50-423,
Page 12 of 31 SG Row Col 3/4TW Elev Volts SG Row Col 3/4TW Elev Volts A
39 71 9
AV2 +0.02 0.15 A
41 101 11 AV4 +0.07 0.22 A
39 71 17 AV3 -0.15 0.51 A
41 101 11 AV5 -0.02 0.2 A
39 71 14 AV4-0.04 0.36 A
41 102 36 AV4 +0.04 2.72 A
39 71 15 AV4 +0.24 0.4 A
41 102 19 AV5+0 0.68 A
39 71 23 AV5 -0.28 1.05 A
41 104 14 AV6 +0.02 0.34 A
39 71 13 AV6 +0.02 0.32 A
41 105 13 AV6 +0.02 0.32 A
39 74 9
AV3 +0.04 0.14 A
42 20 11 AV6+0 0.23 A
39 75 11 AV3 -0.02 0.21 A
42 33 21 AV3 +0.02 0.86 A
39 75 9
AV4 +0.04 0.15 A
42 33 14 AV4-0.11 0.37 A
39 75 13 AV5 -0.13 0.31 A
42 37 14 AV2 +0 0.35 A
39 75 13 AV6 +0.09 0.29 A
42 37 11 AV3 +0.06 0.22 A
39 78 13 AV3 -0.04 0.32 A
42 37 10 AV6+0 0.18 A
40 45 12 AV3 +0.13 0.27 A
42 43 17 AV2 +0.02 0.56 A
40 45 26 AV4 +0.11 1.33 A
42 43 13 AV3 +0.02 0.3 A
40 45 13 AV5 -0.04 0.3 A
42 53 13 AV2 +0.02 0.29 A
40 56 10 AV2 -0.11 0.18 A
42 53 18 AV3 +0.04 0.6 A
40 58 17 AV2 -0.15 0.52 A
42 53 25 AV4 +0.04 1.24 A
40 58 17 AV3 -0.17 0.56 A
42 53 40 AV5 +0.02 3.31 A
40 58 11 AV5 -0.04 0.22 A
42 53 20 AV6 +0.42 0.75 A
40 64 13 AV4-0.02 0.31 A
42 55 13 AV2 -0.02 0.29 A
40 67 12 AV2 +0 0.26 A
42 55 15 AV4 +0.07 0.44 A
40 67 14 AV3 -0.06 0.34 A
42 63 9
AV2 -0.09 0.11 A
40 71 17 AV2 +0.04 0.52 A
42 63 19 AV3 +0.04 0.68 A
40 71 22 AV3 -0.17 0.95 A
42 63 17 AV4 +0.06 0.55 A
40 71 25 AV4-0.26 1.23 A
42 63 14 AV5 +0.11 0.36 A
40 84 10 AV6 +0.02 0.18 A
42 77 10 AV2 -0.04 0.19 A
40 86 12 AV2 -0.04 0.26 A
42 77 14 AV3 +0.11 0.34 A
40 94 16 AV5 -0.15 0.5 A
42 77 25 AV4 +0.02 1.24 A
40 100 12 AV3 -0.04 0.26 A
42 80 11 AV4-0.02 0.22 A
40 102 10 AV4 +0.02 0.17 A
42 85 10 AV2 +0.02 0.18 A
41 61 19 AV3 -0.02 0.7 A
42 85 12 AV4 +0.02 0.24 A
41 61 23 AV4-0.11 1.06 A
42 86 10 AV3 +0.09 0.18 A
41 67 12 AV4+0 0.26 A
42 86 13 AV4 +0.06 0.31 A
41 72 14 AV2 +0.04 0.37 A
42 93 12 AV2 -0.13 0.25 A
41 72 12 AV3 -0.04 0.26 A
42 93 14 AV3 -0.02 0.38 A
41 74 14 AV4 +0.07 0.33 A
42 93 25 AV4 +0.04 1.22 A
41 74 10 AV5 -0.26 0.16 A
42 93 22 AV5 +0 0.96 A
41 87 13 AV4 +0.02 0.32 A
42 98 10 AVl -0.15 0.18 A
41 91 10 AV3 -0.07 0.16 A
42 98 25 AV3 +0.07 1.21 A
41 95 10 AV3 +0.04 0.15 A
42 98 28 AV4 +0.02 1.54 A
41 100 11 AV3 -0.04 0.21 A
42 101 17 AV2 -0.07 0.53
Serial No.24-154 Docket No.
50-423,
Page 13 of 31 SG Row Col
%TW Elev Volts SG Row Col
%TW Elev Volts A
42 101 23 AV3 +0.02 0.99 A
44 96 14 AV4+0 0.36 A
42 101 29 AV4 +0.02 1.72 A
44 96 10 AV5 -0.06 0.17 A
42 101 20 AV5 +0 0.79 A
44 98 13 AV1 +0.02 0.28 A
42 103 15 AV3 -0.15 0.41 A
44 98 20 AV2 -0.19 0.77 A
42 103 18 AV4-0.04 0.63 A
44 98 15 AV4 +0.06 0.4 A
43 20 11 AV6 -0.07 0.23 A
45 45 12 AV3 -0.09 0.25 A
43 36 10 AVl +0.04 0.17 A
45 68 10 AV1 -0.04 0.19 A
43 49 18 AV2 +0.02 0.61 A
45 71 10 AV1 +0.04 0.16 A
43 49 13 AV3 +0.18 0.31 A
45 71 13 AV2 +0.04 0.3 A
43 64 12 AV3 -0.07 0.27 A
45 96 11 AV5 -0.11 0.2 A
43 64 15 AV4 -0.04 0.42 A
45 98 21 AV4 +0.04 0.83 A
43 64 17 AV5 +0.02 0.57 A
45 98 8
AV5 +0.02 0.11 A
43 76 10 AV4 +0.09 0.16 A
45 98 12 AV6+0 0.24 A
43 80 17 AV3 -0.04 0.56 A
45 99 17 AV4 -0.1 0.53 A
43 80 20 AV4+0 0.76 A
45 99 11 AV5 +0.11 0.22 A
43 80 12 AV5 -0.13 0.27 A
45 101 10 AV6 -0.02 0.16 A
43 80 14 AV6 +0.07 0.34 A
46 97 9
AV5 +0.07 0.12 A
43 85 9
AV3 -0.35 0.14 A
46 98 10 AV5 +0.07 0.17 A
43 87 21 AV2 +0.09 0.8 A
46 99 13 AV2 +0.13 0.28 A
43 87 21 AV4+0 0.81 A
46 99 20 AV4 +0.02 0.72 A
43 87 19 AV5 -0.06 0.7 A
46 99 19 AV5 +0.04 0.66 A
43 89 13 AV3 +0.09 0.3 A
46 99 10 AV6 -0.02 0.19 A
43 95 9
AV6 -0.11 0.15 A
47 71 10 AV2 +0.04 0.16 A
43 96 11 AV5 -0.04 0.2 A
47 85 7
AV1 +0.11 0.08 A
43 98 15 AV4 +0.04 0.39 A
47 98 19 AV3 +0.04 0.68 A
43 98 12 AV5 -0.09 0.25 A
47 99 13 AV6 +0.02 0.32 A
43 99 16 AV4 +0.02 0.47 A
48 25 7
AV3 -0.02 0.08 A
43 99 9
AV5 -0.07 0.12 A
48 26 9
AV2 +0.11 0.15 A
43 101 11 AV3 +0.02 0.21 A
48 26 9
AV5 -0.06 0.12 A
43 101 18 AV4 +0.02 0.6 A
48 26 10 AV6 -0.11 0.18 A
43 101 15 AV5 +0.04 0.41 A
48 96 11 AV6 +0.02 0.23 A
43 102 20 AV4+0 0.74 A
49 95 13 AV2+0 0.32 A
43 102 17 AV5 +0.04 0.56 A
49 95 12 AV4 -0.04 0.26 A
43 103 13 AV5 +0.04 0.31 A
49 96 20 AV6+0 0.74 A
44 64 30 AV2 +0.02 1.76 A
50 29 10 AV4 +0.04 0.17 A
44 64 21 AV3 -0.11 0.87 A
50 29 12 AV5 -0.02 0.24 A
44 74 19 AV4 +0.04 0.68 A
50 29 11 AV6 +0.02 0.23 A
44 74 27 AV5 +0 1.39 A
50 44 9
AV3 -0.04 0.15 A
44 74 20 AV6 +0.25 0.73 A
50 44 16 AV4 -0.13 0.48 A
44 75 21 AV3 +0.02 0.85 A
50 44 18 AV4 +0.2 0.62 A
44 96 13 AV2 +0.04 0.28 A
50 44 33 AV5 +0.02 2.26
Serial No.24-154 Docket No.
50-423,
Page 14 of 31 SG Row Col
%TW Elev Volts SG Row Col
%TW Elev Volts A
50 44 13 AV6 +0.02 0.32 B
30 12 10 AV2 +0.02 0.19 A
50 50 19 AV4-0.22 0.65 B
30 12 15 AV5 -0.19 0.44 A
50 76 25 AV2 +0.02 1.17 B
32 108 14 AV4 -0.06 0.33 A
50 76 24 AV3 +0.04 1.07 B
33 12 15 AV2 +0 0.42 A
50 76 33 AV4 +0.11 2.21 B
33 12 16 AV5 +0 0.47 A
50 82 17 AV2 +0.02 0.57 B
33 20 14 AV4 +0.04 0.35 A
50 82 30 AV3 -0.13 1.82 B
33 39 11 AV3 +0.02 0.22 A
50 82 22 AV4 -0.13 0.94 B
33 109 16 AV2+0 0.49 A
50 86 15 AV2 -0.02 0.43 B
33 109 18 AV3 +0 0.59 A
50 87 24 AV2 -0.15 1.11 B
33 109 9
AV6+0 0.15 A
50 87 22 AV3 -0.15 0.91 B
34 18 9
AV3 +0.07 0.12 A
50 87 16 AV4+0 0.45 B
34 18 11 AV4 +0.13 0.2 A
50 87 13 AV5 +0.07 0.31 B
34 71 10 AV3 +0.04 0.19 A
51 31 9
AV2 +0.17 0.14 B
34 109 10 AV2 -0.02 0.19 A
51 64 15 AV3 +0.07 0.4 B
34 109 21 AV3 -0.02 0.87 A
51 64 11 AV4 -0.04 0.2 B
34 109 14 AV5 -0.04 0.37 A
51 65 9
AVl+0 0.13 B
34 109 10 AV6+0 0.18 A
51 65 10 AV2 -0.02 0.19 B
34 110 11 AV3 +0.02 0.21 A
51 65 13 AV3 +0 0.32 B
35 103 12 AV4 +0.11 0.24 A
51 65 12 AV4 +0.09 0.25 B
35 103 11 AV6 -0.11 0.2 A
51 65 21 AV5 +0.02 0.84 B
35 106 11 AV3 +0.04 0.2 A
51 65 13 AV6 +0.07 0.32 B
35 106 17 AV4+0 0.52 A
51 66 11 AV2 +0.02 0.2 B
35 106 11 AV6 -0.04 0.21 A
51 66 11 AV3 +0.09 0.23 B
36 22 12 AV6+0 0.25 A
51 79 10 AV3 +0.02 0.16 B
36 39 12 AV2 +0.22 0.26 A
52 66 26 AV4 +0.09 1.3 B
36 39 13 AV3 -0.02 0.32 A
52 90 10 AV2 +0.19 0.19 B
36 39 12 AV4 +0.02 0.25 A
52 90 15 AV3 -0.02 0.39 B
36 39 18 AV5 -0.04 0.62 A
52 90 12 AV4 +0.02 0.25 B
36 39 17 AV6 +0.33 0.51 A
53 81 13 AVl+0 0.29 B
36 67 15 AV6 +0.07 0.41 A
53 81 26 AV3 +0.04 1.37 B
37 100 11 AV4-0.07 0.23 A
53 81 11 AV4 +0.04 0.23 B
37 103 11 AV2 -0.02 0.22 A
53 81 9
AV5 -0.04 0.12 B
37 104 14 AV3 -0.04 0.36 A
54 35 13 AV4-0.07 0.27 B
37 104 10 AV4-0.04 0.18 A
54 35 19 AV5 -0.02 0.71 B
38 104 14 AV3 -0.02 0.36 A
54 35 14 AV6+0 0.34 B
38 104 23 AV4-0.18 1.02 A
54 49 14 AV2 +0.04 0.36 B
38 104 10 AV5 +0.04 0.19 A
54 49 13 AV3 +0.09 0.31 B
39 30 12 AV2 +0.15 0.25 A
56 41 10 AV2 +0.09 0.16 B
39 30 10 AV3 +0.11 0.19 A
58 54 11 AVl -0.69 0.23 B
39 30 13 AV4 +0.02 0.28 A
59 64 10 AV6 +0.54 0.17 B
39 30 13 AV5 -0.11 0.28
Serial No.24-154 Docket No.
50-423,
Page 15 of 31 SG Row Col 3/4TW Elev Volts SG Row Col 3/4TW Elev Volts B
39 96 14 AV3 -0.04 0.33 B
48 25 10 AV6 -0.04 0.18 B
40 23 13 AV2 -0.09 0.31 B
49 27 11 AVl +0.11 0.2 B
40 23 10 AV3 +0.04 0.19 B
49 27 9
AV2 +0.02 0.14 B
40 23 15 AV4+0 0.43 B
49 27 9
AV5 +0.24 0.13 B
40 23 15 AV5 +0.02 0.4 B
50 29 11 AV2 -0.02 0.23 B
40 24 16 AV3 +0.13 0.47 B
50 29 12 AV6 +0.04 0.25 B
40 24 18 AV4 +0.07 0.61 B
50 72 13 AV3 -0.11 0.29 B
40 24 13 AV5 +0 0.31 B
50 88 18 AV2 +0.13 0.62 B
41 34 15 AV2 +0.35 0.42 B
50 88 21 AV3 -0.07 0.85 B
41 34 14 AV3 +0.13 0.33 B
50 88 24 AV4+0 1.07 B
41 34 32 AV4 +0.44 2.05 B
50 88 13 AV5 +0.04 0.3 B
41 34 32 AV5 +0 2.05 B
50 88 10 AV6 -0.07 0.16 B
41 34 12 AV6 +0.02 0.24 B
51 91 20 AV4+0 0.76 B
41 50 15 AV3 +0.07 0.4 B
51 91 16 AV5 +0.02 0.45 B
41 50 24 AV4 +0.07 1.14 B
51 91 10 AV6 -0.02 0.19 B
41 69 10 AV3 +0.02 0.19 B
54 35 11 AV2 +0.02 0.21 B
41 69 21 AV4-0.25 0.8 B
54 35 12 AV4-0.02 0.26 B
41 69 31 AV5 -0.04 1.89 B
54 35 13 AV5 +0 0.31 B
41 77 12 AV2 -0.04 0.27 B
54 35 11 AV6 +0.04 0.22 B
41 77 17 AV3 +0.1 0.57 B
54 36 29 AV5 +0.02 1.71 B
41 77 17 AV4+0 0.53 B
54 36 16 AV6 -0.15 0.46 B
41 77 20 AV5 +0 0.72 B
54 37 10 AVl -0.37 0.17 B
42 19 10 AVl +0.02 0.18 B
54 45 9
AV2+0 0.14 B
42 21 17 AV2 +0.07 0.52 B
55 84 14 AV6 -0.05 0.33 B
42 21 14 AV3 -0.2 0.36 B
56 41 10 AV3 +0.15 0.18 B
42 21 20 AV4 +0.11 0.73 B
56 42 14 AV6 +0.07 0.38 B
42 21 26 AV5 +0.04 1.29 B
56 71 11 AV2 +0.16 0.21 B
42 21 14 AV6 +0.09 0.35 B
56 81 12 AVl +0.02 0.26 B
42 33 13 AV2 +0.02 0.28 B
57 70 10 AV2 +0.04 0.17 B
42 33 11 AV4+0 0.21 B
58 74 11 AV4-0.02 0.2 B
42 33 15 AV5 -0.09 0.43 B
58 75 20 AV5 -0.04 0.75 B
42 96 20 AV2 +0.09 0.73 B
59 65 19 AV2 +0.72 0.7 B
42 96 14 AV3 -0.02 0.34 C
15 66 12 AVl-0.02 0.27 B
42 96 11 AV4+0 0.23 C
25 8
13 AVl +0.33 0.29 B
42 96 11 AV5 -0.02 0.2 C
25 115 9
AVl +0.09 0.14 B
43 86 11 AV4 +0.04 0.21 C
25 116 23 AV6 +0.56 1
B 43 100 23 AV3 -0.24 1.04 C
27 44 11 AV2 +0.02 0.21 B
43 100 27 AV4 -0.04 1.38 C
34 14 11 AV2 -0.04 0.23 B
43 100 12 AV6 -0.11 0.27 C
34 14 13 AV5 +0.06 0.3 B
45 22 10 AV6 -0.29 0.16 C
36 15 10 AV5 +0.11 0.16 B
46 99 14 AV4 +0.07 0.36 C
36 15 10 AV6 +0.15 0.19
Serial No.24-154 Docket No.
50-423,
Page 16 of 31 SG Row Col
%TW Elev Volts SG Row Col
%TW Elev Volts C
37 15 22 AV2 -0.04 0.97 C
45 100 11 AV6 +0.05 0.23 C
37 15 12 AV3 +0 0.27 C
46 33 13 AV6 +0.7 0.32 C
37 15 12 AV4 +0.02 0.25 C
46 97 8
AVl +0.05 0.1 C
37 15 26 AV5 +0.26 1.28 C
46 97 7
AV3 +0.02 0.08 C
37 15 14 AV6 +0.13 0.35 C
47 99 15 AV6 +0.02 0.39 C
37 88 13 AV3 -0.04 0.29 C
48 26 10 AV4 +0.1 0.16 C
39 17 21 AV2 +0 0.8 C
48 98 12 AV3 +0 0.24 C
39 17 13 AV3 +0.02 0.29 C
48 98 10 AV4 +0.02 0.17 C
39 17 18 AV4-0.05 0.6 C
48 98 11 AV6+0 0.21 C
39 17 19 AV5 +0.09 0.7 C
49 96 20 AV5 +0 0.78 C
39 17 14 AV6 +0.12 0.33 C
49 96 24 AV6 -0.12 1.13 C
39 79 15 AV3 -0.7 0.42 C
50 28 10 AV2 -0.02 0.17 C
39 107 9
AV6 -0.16 0.14 C
50 28 17 AV5 +0.07 0.54 C
41 42 26 AV3 +0.05 1.3 C
50 93 11 AV5 -0.09 0.22 C
41 42 15 AV4-0.02 0.44 C
50 93 13 AV6 +0.05 0.32 C
41 54 12 AVl +0.09 0.26 C
50 95 10 AV6 +0.09 0.16 C
41 54 18 AV3 -0.19 0.58 C
51 92 10 AV6 +0.17 0.17 C
41 54 16 AV4-0.04 0.45 C
54 35 12 AV5 +0.02 0.25 C
41 54 20 AV5 +0.04 0.76 C
54 36 15 AV4 +0.06 0.43 C
41 62 25 AV2 -0.28 1.26 C
54 36 11 AV5 +0.02 0.23 C
41 62 19 AV3 -0.33 0.71 C
54 86 9
AVl +0.09 0.14 C
41 62 30 AV3 +0.46 1.84 C
56 41 9
AV2+0 0.14 C
41 62 21 AV4-0.31 0.83 C
56 41 13 AV4+0 0.31 C
41 62 32 AV4 +0.37 2.05 C
56 41 24 AV5 +0.07 1.1 C
41 62 29 AV5 -0.32 1.68 C
56 41 15 AV6 +0.07 0.4 C
41 62 15 AV6 -0.22 0.42 C
56 44 8
AV4+0 0.09 C
41 65 16 AV4 +0.7 0.47 C
58 49 11 AV5 +0.11 0.2 C
41 65 16 AV5 +0 0.5 D
9 121 11 AV6 +0.06 0.22 C
41 105 11 AV6 +0.02 0.21 D
24 117 19 AVl+0 0.65 C
42 20 16 AV2 +0.02 0.48 D
25 93 10 AV5 -0.32 0.18 C
42 20 22 AV3 +0 0.97 D
25 115 12 AVl +0.9 0.26 C
42 20 24 AV4-0.02 1.12 D
26 8
13 AV6 +0.15 0.31 C
42 20 23 AV5 +0.02 0.99 D
26 115 15 AVl +0.47 0.42 C
42 20 20 AV6 +0.07 0.75 D
26 116 10 AVl+0 0.16 C
42 23 15 AV2 +0.05 0.44 D
27 115 14 AVl +0.25 0.35 C
42 23 20 AV3 +0.07 0.78 D
27 115 14 AV6 -0.48 0.38 C
42 23 29 AV4-0.02 1.7 D
28 8
12 AVl -0.17 0.24 C
42 23 27 AV5 +0 1.47 D
28 8
13 AV6 +0.25 0.31 C
42 103 10 AV3 +0 0.18 D
28 114 27 AV2 +0.2 1.4 C
45 57 14 AV2 +0 0.37 D
28 114 10 AV5 -0.2 0.19 C
45 100 10 AV5 -0.08 0.18 D
28 114 11 AV5 +0.18 0.2
Serial No.24-154 Docket No.
50-423,
Page 17 of 31 SG Row Col
%TW Elev Volts SG Row Col
%TW Elev Volts D
29 113 14 AV2 -0.04 0.35 D
37 106 19 AV3 +0.09 0.67 D
29 113 18 AV5 -0.24 0.61 D
37 106 30 AV4 +0.04 1.74 D
30 113 12 AV2 +0.04 0.24 D
37 106 19 AV5 -0.02 0.68 D
30 114 13 AVl +0.17 0.32 D
37 106 14 AV6 +0.05 0.35 D
30 114 10 AV5 -0.08 0.18 D
38 21 13 AV5 +0.09 0.3 D
30 114 23 AV6 +0.2 1.04 D
38 21 10 AV6 -0.07 0.19 D
31 99 11 AV2 -0.14 0.22 D
38 94 10 AV2 -0.14 0.17 D
31 99 11 AV5 +0.04 0.2 D
38 95 9
AV5 +0.1 0.13 D
31 99 10 AV6 +0.02 0.16 D
38 98 11 AV2 +0.09 0.23 D
32 112 13 AV5 -0.04 0.28 D
38 98 14 AV4 +0.06 0.38 D
33 86 9
AV3 +0.11 0.13 D
40 32 12 AV2 +0.03 0.24 D
33 86 12 AV4 +0.04 0.24 D
40 99 13 AV2 -0.16 0.31 D
33 109 10 AV2 +0.02 0.17 D
40 99 12 AV3 +0 0.27 D
33 109 14 AV5 +0.02 0.36 D
40 99 26 AV4-0.02 1.29 D
34 109 10 AV2 -0.02 0.16 D
40 99 31 AV5 +0.06 1.92 D
35 99 16 AV2 +0.17 0.46 D
40 100 13 AV4 +0.02 0.31 D
35 99 13 AV5 +0 0.31 D
40 100 16 AV5 +0.04 0.46 D
35 102 13 AV5 -0.02 0.28 D
40 100 13 AV6+0 0.3 D
35 103 17 AV5 -0.02 0.57 D
40 101 11 AV3 +0.16 0.2 D
35 107 10 AV4-0.02 0.16 D
40 101 9
AV4+0 0.15 D
35 108 17 AV3 +0.09 0.53 D
40 101 10 AV5 +0.04 0.17 D
35 108 16 AV4-0.04 0.47 D
40 101 14 AV6 +0.05 0.34 D
35 109 15 AV4 +0.08 0.42 D
40 102 11 AV2 +0.13 0.21 D
35 109 10 AV5 +0.1 0.17 D
40 102 10 AV3 -0.04 0.16 D
36 34 10 AV2 -0.04 0.16 D
40 102 22 AV4 +0.04 0.93 D
36 82 10 AV3 +0.09 0.15 D
40 102 16 AV5 +0.06 0.47 D
36 88 11 AV2 -0.14 0.23 D
40 102 13 AV6 +0.02 0.28 D
36 88 10 AV3 +0.04 0.19 D
40 103 11 AVl +0.02 0.23 D
36 88 12 AV5 +0.02 0.26 D
40 103 20 AV2 -0.02 0.78 D
36 97 14 AV2 -0.14 0.36 D
40 103 24 AV3 +0.04 1.07 D
36 108 11 AV2 +0.04 0.21 D
40 103 31 AV4 +0.24 1.95 D
37 93 12 AV2 +0.04 0.24 D
40 103 26 AV5 +0.06 1.37 D
37 93 16 AV3 -0.04 0.48 D
40 103 15 AV6 +0.02 0.43 D
37 101 20 AV2 -0.16 0.76 D
41 26 14 AV2 -0.08 0.38 D
37 101 15 AV3 +0 0.43 D
41 26 27 AV5 +0.02 1.43 D
37 101 14 AV4-0.02 0.36 D
41 26 28 AV6 -0.27 1.6 D
37 103 11 AV2 +0 0.22 D
41 29 10 AV4 +0.09 0.16 D
37 103 11 AV3 +0.04 0.21 D
41 29 9
AV6 -0.02 0.15 D
37 103 14 AV5 -0.02 0.36 D
41 30 8
AV2 +0.02 0.1 D
37 103 11 AV6+0 0.22 D
41 30 14 AV3 +0.08 0.33 D
37 106 13 AVl +0.07 0.31 D
41 30 16 AV4 +0.09 0.5
Serial No.24-154 Docket No.
50-423,
Page 18 of 31 SG Row Col
%TW Elev Volts SG Row Col
%TW Elev Volts D
41 30 13 AVS +0.02 0.28 D
48 96 17 AVS +0.05 0.56 D
41 31 10 AV2 +0.05 0.18 D
48 96 13 AV6 +0.02 0.29 D
41 39 16 AV2 -0.11 0.49 D
49 62 21 AVl +0.27 0.86 D
41 39 17 AV3 +0.11 0.56 D
49 62 24 AV2 -0.17 1.08 D
41 39 21 AV4 +0.17 0.81 D
49 62 30 AV3 +0.19 1.78 D
41 39 25 AVS +0 1.19 D
49 62 20 AV4 +0.06 0.73 D
41 39 10 AV6 -0.16 0.19 D
49 66 13 AVl +0.02 0.29 D
41 78 12 AV2 +0 0.26 D
49 66 28 AV2 -0.07 1.57 D
41 78 23 AV3 +0.24 0.98 D
49 66 16 AV3 -0.17 0.47 D
41 78 18 AV4 +0.3 0.63 D
49 67 22 AV2 +0.02 0.92 D
41 78 14 AVS +0.05 0.34 D
49 67 19 AV3 +0.17 0.67 D
41 87 10 AV3 +0.02 0.19 D
49 67 10 AV4 +0.04 0.16 D
41 90 13 AVl +0.16 0.32 D
49 69 10 AV2 +0.06 0.19 D
41 90 13 AV3 +0.02 0.31 D
49 70 11 AV2 -0.1 0.23 D
42 19 12 AVS +0.44 0.24 D
49 86 11 AV3 +0.04 0.2 D
42 103 13 AV2 -0.05 0.29 D
49 95 17 AV2 +0.02 0.54 D
43 20 11 AV6 +0.1 0.2 D
49 95 19 AV3 -0.13 0.65 D
43 25 11 AVS +0 0.21 D
49 95 20 AV4-0.02 0.77 D
43 33 11 AV3 +0.15 0.2 D
so 28 12 AV6 +0.02 0.24 D
43 95 13 AV4 +0.06 0.3 D
so 80 10 AV2 +0.09 0.18 D
43 95 20 AVS +0.11 0.79 D
so 80 13 AV3 +0.02 0.3 D
43 100 11 AV3 +0.08 0.21 D
so 83 10 AVl +0.05 0.19 D
43 100 19 AV4 -0.02 0.71 D
so 83 17 AV2 +0.02 0.52 D
43 100 11 AVS -0.12 0.22 D
so 83 10 AV3 +0.02 0.18 D
43 100 12 AV6 +0.09 0.25 D
so 90 9
AV1+0 0.12 D
43 102 14 AVS +0.02 0.33 D
51 87 9
AVS +0.09 0.13 D
43 102 13 AV6 +0.07 0.28 D
51 89 13 AV6+0 0.31 D
44 21 12 AVl +0.02 0.23 D
52 33 9
AVS +0.05 0.14 D
45 22 11 AV6 -0.07 0.2 D
52 67 8
AV3 +0.13 0.09 D
45 41 15 AV3 -0.09 0.44 D
52 67 20 AV4-0.02 0.78 D
45 41 10 AV4 -0.28 0.18 D
52 67 13 AVS+0 0.29 D
45 47 10 AV6 +0.08 0.17 D
52 69 11 AV2 +0.02 0.23 D
45 92 11 AV2 -0.07 0.2 D
52 87 17 AVS +0.09 0.52 D
45 96 11 AV2 -0.02 0.22 D
52 87 13 AV6 +0.02 0.32 D
45 96 11 AV3 +0.06 0.22 D
52 88 10 AVl-0.06 0.16 D
45 96 8
AVS +0 0.11 D
52 88 17 AV2 +0.02 0.57 D
47 24 11 AVl +0.04 0.22 D
52 88 11 AV3 +0.02 0.23 D
47 96 13 AVS -0.02 0.3 D
52 88 16 AV4+0 0.45 D
47 98 10 AVS +0.13 0.18 D
52 88 11 AVS +0.09 0.21 D
48 25 11 AV6 +0.09 0.23 D
53 33 13 AV6+0 0.32 D
48 94 12 AV6 -0.02 0.27 D
53 34 10 AV6 +0.02 0.16
Serial No.24-154 Docket No.
50-423,
Page 19 of 31 SG Row Col 3/4TW Elev Volts SG Row Col
%TW Elev Volts D
53 35 12 AV4 +0.06 0.27 D
55 75 16 AV6+0 0.48 D
53 35 17 AV5 +0.02 0.52 D
55 84 12 AV3 -0.04 0.27 D
53 35 17 AV6 -0.07 0.57 D
55 84 22 AV5 -0.02 0.9 D
53 36 10 AV6 -0.05 0.18 D
55 84 10 AV6 +0.04 0.18 D
53 70 12 AV2 +0.04 0.27 D
56 43 13 AVl -0.06 0.31 D
54 49 16 AV2 +0 0.5 D
58 59 11 AVl -0.28 0.2 D
54 49 21 AV3 +0.02 0.81 D
54 49 11 AV4 +0.04 0.21 D
54 87 11 AV1+0 0.22 D
55 40 15 AV6 +0.02 0.41
- e. Number of tubes plugged during the inspection outage for each degradation mechanism, Based on inspection results, two (2) tubes were plugged during the 3R22 outage.
Table 5: Summary of 3R22 Plugging.
S/G Row Col Hot-Leg Cold-Leg Degradation Mechanism SG-A 42 53 Plugged/Stabilized Plugged AVB Wear SG-A 50 76 Plugged/Stabilized Plugged AVB Wear
- f. The number and percentage of tubes plugged to date and the effective plugging percentage in each steam generator.
Table 6 provides the total number of tubes plugged to date and the effective plugging percentage in each SG.
Table 6: Number Tubes Plugged to Date SGA SG B SG C SG D Prior to 3R22 53 26 23 91 During 3R22 2
0 0
0 Total After 3R22 55 26 23 91 Percentage 0.978 0.462 0.409 1.617 Overall Percentage 0.867 Since no sleeving has been performed in the MPS3 steam generators, the effective plugging percentage is the same as the actual plugging percentage.
Serial No.24-154 Docket No.
50-423,
Page 20 of 31
- g. The results of condition monitoring, including the results of tube pulls and in-situ
- testing, No tubes were pulled, and no in-situ pressure tests were performed.
The condition monitoring assessment concluded that the structural integrity, operational leakage, and accident induced leakage performance criteria were not exceeded during the operating interval preceding 3R22.
To perform the CM assessment for AVB wear, a CM limit curve was developed using the EPRI Flaw Handbook Calculator. Since the circumferential extent of AVB wear is <135°, it is appropriate to use the EPRI Flaw Handbook "Part-Through wall Axial Volumetric Degradation" flaw model to evaluate the CM limit. The Flaw Handbook Calculator uses Monte Carlo methods to model the various uncertainties. The CM limit includes material property uncertainties, model uncertainties, and NOE depth sizing uncertainties to establish a curve of allowable NOE measured depths (i.e., the CM limit curve).
Using the input parameters summarized in the DA, the 95/50 CM limit curve of Figure 1 was developed. This limit curve is applicable to the AVB wear indications reported at MP3 during 3R22.
On Figure 1, the depths of all AVB wear reported during 3R22 are plotted with the assumption that the axial extent of the wear was 2.5 inches (purposely staggered about 2.5" to reveal each SG's findings). This is a very conservative assumption representative of the upper limit of near-parallel contact between the AVBs and tubes. It should also be noted that there is no significant reduction in the depth limit curve from 2.5 inches to 3 inches and beyond. Since all the reported AVB wear depths (including the maximum, 40% TW), lie below the CM Limit Curve, the CM requirements for structural integrity are satisfied for AVB wear.
To perform the CM assessment for TSP and FOB wear, a CM limit curve was developed using the EPRI Flaw Handbook Calculator. Monte Carlo methods were used to incorporate material property uncertainties, model uncertainties and NOE depth sizing uncertainties to establish a curve of allowable NOE measured depths. Because of eddy current coil "look-ahead," the +Point' probe overestimates the length of degradation. Therefore, the lengths as-measured are upper-bound estimates of the actual flaw length, and no additional allowance for length sizing uncertainty is included in the CM curve.
Using the input parameters summarized in the DA, together with the EPRI Flaw Handbook
"<135° Part-Through-wall Axial Volumetric Degradation" model, the 95/50 CM limit curve of Figure 2 was developed. This limit curve is applicable to the TSP wear indications (including any baffle plate wear) reported at MP3 during 3R22.
On Figure 2, the depths of all TSP and FOB wear reported in each of the four SGs during 3R22 are plotted using the +Point' measured axial lengths and depths. Since all the reported TSP/FOB wear depths lie below the CM Limit Curve, the CM requirements for structural integrity are satisfied for TSP and FOB wear at 3R22.
80 70 60 50 40 30 20 10 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0
--0.0
-0.100 Serial No.24-154 Docket No.
50-423,
Page 21 of 31 Figure 1: CM Limit Curve for AVB Wear CM Limit Curve for AVB Wear ETSS 96041.3 CMlimit SGA
~ SG B
- SG C.
SG D 0.5 1.5 2.5 3.5 Figure 2: CM Limit Curve for TSP and FDB Wear
- t.
0.100 0.300 CM Limit Curve for TSP/FDB Wear ETSS 96910.1 0.500 0.700 0.900 1.100
-- CM Limit SGA SG B SGC SGD 1.300 1.500
Serial No.24-154 Docket No.
50-423,
Page 22 of 31 Volumetric degradation caused by foreign object wear and fabrication processes is evaluated in this section. All these indications (59 total) are identified in Figure 3 through Figure 5 along with the ETSSs that were used to measure each indication. A unique CM limit curve was developed to capture the sizing uncertainty for each unique ETSS used.
Each CM limit curve in this section is based on use of the EPRI Flaw Handbook "<135° Part-Through-wall Axial Volumetric Degradation" model.
4 of the volumetric flaws (fabrication indication) were sized using ETSS 21998.1.
Since the flaws lie below the 95/50 CM limit curve illustrated in Figure 3, the CM requirements for structural integrity are satisfied.
53 of the volumetric flaws were sized as foreign object wear using ETSS 27901.1.
Since the flaws lie below the 95/50 CM limit curve illustrated in Figure 4, the CM requirements for structural integrity are satisfied.
2 of the volumetric flaws were sized as foreign object wear using ETSS 27902.1.
Since the flaws lie below the 95/50 CM limit curve illustrated in Figure 5, the CM requirements for structural integrity are satisfied.
100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0.0
-0.100 Figure 3: CM Limit Curve for Volumetric Flaw Using ETSS 21998.1 CM Limit Curve for VOL lndiations ETSS 21998.1 0.100 0.300 0.500 0.700 0.900 1.100
~
CMLimit SGA
.t.
Serial No.24-154 Docket No.
50-423,
Page 23 of 31 Figure 4: CM Limit Curve for Foreign Object Wear Flaws Using ETSS 27901.1 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 I :
- I I....
- I t
I 10.0 1! 1 ~! I 0.0
-0.100 0.100 0.300 CM Limit Curve for FOW lndiations ETSS 27901.1 0.500 0.700 0.900 1.100
A SG 8 SGC SG D 1.300 1.500 Figure 5: CM Limit Curve for Foreign Object Wear Flaw Sized with ETSS 27902.1 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0
--o.o -
-0.100 0.100 0.300 CM Limit Curve for FOW lndiations ETSS 27902.1 0.500 0.700 0.900 1.100
-+- CM Limit SGA A
SG D 1.300 1.500
Serial No.24-154 Docket No.
50-423,
Page 24 of 31 It is a requirement of the IAGL that current inspection results be used to validate prior operational assessment (OA) inputs and assumptions. This ensures that any adjustments that may be necessary going forward are incorporated into the current outage OA. A review of the most recent OA for each steam generator (3R21 for all four SGs) was performed and the key inputs and assumptions were compared with the results from the current outage (3R22). This review, summarized in Table 7, shows that the as-found conditions were bounded by the projections from the previous OA for all cases.
Table 7: Summary of Prior OA Validation Prior 3R21 (spring 2022) OA Observed during the inspection Assumptions 3R22 Outage projection satisfied AVB Wear 95/50 growth rate of The biggest 95/50 growth rate was Yes 4.0% TW/EFPY 1.564 % TW/EFPY TSP/ FOB Maximum growth rate of The Maximum growth rate was Yes Wear 11.0 % TW/EFPY 3.13 % TW/EFPY No growth for repeat volumetric degradation due to (foreign No growth observed in non-objects, fabrication related, and support volumetric degradation Non-Support lancing sled).
previously left in service.
Volumetric Yes Degradation If growth occurs, or new A few flaws were newly reported, degradation develops, it will not but none exceeded structural exceed structural performance performance criteria.
criteria prior to 3R22.
Circumferential Probability of Burst< 0.002%
ODSCC No ODSCC was detected Yes Probability of Leakage< 0.074%
Operational Projected: Zero GPM No measurable leakage in any SG Yes Leakage since the last ISi EFPY EFPY::;; 1.5 EFPY EFPY = 1.279 Yes 3(NOPD) 3*(1340) = 4020 psid Bounding 3990 psid Yes
Serial No.24-154 Docket No.
50-423,
Page 25 of 31 The Operational Assessment (OA) must demonstrate that the three performance criteria will not be exceeded prior to the next scheduled examination in each steam generator.
Consistent with the Dominion Fleet Administrative Procedure for performing CMOAs, this operational assessment addresses both existing degradation mechanisms and bounding potential degradation mechanisms over the projected inspection interval. Since all four SGs were examined during the current 3R22 (fall 2023) inspection without finding corrosion related degradation, and with MP3 planning to adopt TSTF-577 shortly after the 3R22 outage, this OA has been evaluated for a 3-cycle inspection interval totaling 4.5 EFPY. This interval is conservative considering that 1.4 EFPY per cycle is typically bounding for MP3.
The MP3 steam generators (all SGs) have operated for a single cycle of 1.279 EFPY since the last inspection at 3R21 (spring 2022).
Table 8: OA for Structure Wear Degradation Mechanism Maximum Depth(%)
Structural Limit Depth(%)
Predicted at 3R25 AVB Wear 63.2 67 TSP/FOB Wear 65.1 69.1 A single circumferentially oriented ODSCC indication was identified for the first time, above the H* distance, in the MP3 SG tubes during the previous 3R21 outage (2022). Therefore, circumferential oriented ODSCC is listed as an existing degradation mechanism. Following the methodology described in the IAGL, a fully probabilistic multi-cycle OA analysis was performed.
The distribution of 3R25 worst-case degraded tube burst pressures resulting from this analysis is shown in Figure 6. This figure demonstrates that the lower 95/50 (i.e., the 5th percentile) burst pressure, 7360 psi satisfies the SIPC limit of 4080 psi; therefore, it is concluded that circumferential ODSCC at the TTS will not cause the structural integrity performance criteria to be exceeded in the MP3 SGs prior to 3R25. The projected total upper 95/50 leakage (GPM) under limiting accident conditions is zero; therefore, it is concluded that circumferential ODSCC at the TTS will not cause the accident-induced leakage performance criteria to be exceeded prior to 3R25. These conclusions are also presented below in Table 9 in terms of the probability of burst (POB) at 3~P and the probability of leakage (POL) under accident conditions.
Serial No.24-154 Docket No.
50-423,
Page 26 of 31 Figure 6: 3R25 Worst Case Burst Pressure - Circumferential ODSCC @TTS
~
- E n,
.c e 0.20 ~----------------------,,,-----------,
3R25 Min BP 0.15 f
I I ' ' ' * ' '
- I,,,
- a.
G) 0.10 I
-~
1u
- 5 E
- I u Lower 95/50: 7360 psi I
I /
I /
I '
3XNOf D: 4080 psi
-- J ----
Probability: 0.05
,' I I
/
I I
/
I I
I I
0.05 I
I 0.00 +----..,..*- -----.-----____,-...,,-=-:....:..-..-- -- ----,---1L------..------T"""------I 3,000 4,000 5,000 6,000 7,000 8,000 9,000 Projected 3R25 Worst Case Burst Pressure (psi)
Table 9: Probabilities of Burst and Leakage at (3*NOPD)
Circumferential ODSCC @TTS Population POB at 3~P POL Full Bundle 0.030%
2.03%
SG Program Maximum 5%
5%
Allowable 10,000 The OA also considers two bonding "potential" degradation mechanisms, neither of which have been identified in the MP3 SGs. These mechanisms which could potentially develop (i.e., "potential" degradation mechanisms) are axial ODSCC at TSPs and axial ODSCC at dent/ dings.
Although no indications of axial ODSCC have been identified in the MP3 SGs, hypothetical axial ODSCC at tube support plates (TSPs) (which bounds axial ODSCC at tube free-span locations) were evaluated. This degradation mechanism is considered bounding because ECT bobbin probe examination methods are relied upon to detect this mechanism in non-high stress tubes. The bobbin probe probability of detection (POD) is less favorable than that of the +Point' probe. In addition, the lengths of cracks that develop at TSPs are typically greater than the lengths of those that develop elsewhere within the SGs. Even
Serial No.24-154 Docket No.
50-423,
Page 27 of 31 though all high stress tubes (Tier-1 tubes), in all four SGs during 3R22, were examined full length using the array probe (in addition to the bobbin probe), this evaluation conservatively assumes that the 3R22 examination relied entirely upon the bobbin probe POD curve for detection of axial ODSCC at TSPs.
Following the methodology described in the IAGL, a fully probabilistic multi-cycle OA analysis was performed. The software simulates the life cycle of a susceptible tube population and generates Monte Carlo projections of both detected and undetected, flaws for multiple cycles of operation. The simulation considers inspection POD, new flaw initiation, and growth to calculate burst probability and accident-induced leakage at time points of interest. These key parameters are discussed below.
The distribution of 3R25 worst-case degraded tube burst pressures resulting from this analysis is shown in Figure 7. This figure demonstrates that the lower 95/50 (i.e., the 5th percentile) burst pressure, 4736 psi satisfies the SIPC limit of 4080 psi; therefore, it is concluded that axial ODSCC at tube support plates will not cause the structural integrity performance criteria to be exceeded in the MP3 SGs prior to 3R25. The projected total upper 95/50 leakage (GPM) under limiting accident conditions is zero; therefore, it is concluded that axial ODSCC at tube support plates will not cause the accident-induced leakage performance criteria to be exceeded prior to 3R25. These conclusions are also presented below in Table 10 in terms of the probability of burst (POB) at 3iiP and the probability of leakage (POL) under accident conditions.
Figure 7: 3R25 Worst Case Burst Pressure - Axial ODSCC @TSPs 0.25 ~-------------------------
0.20
~
~ 0.15 *
..c e 0..
Q)
~
1ij "5 0.10 E
- s u 0.05 I l
3R25 Min BP
/
I I
I,
I,,
I I
I ' ',,,
/
/,,
Lower 95/50: 4736 psi i
/'
I I
I,,'
--~------ Probability: 0.05 3XNOPD: 4080 psi,
,,,' *1 I
I I
I
-~--~-
I I
~**
~
I 0.00.+-...........==,:=...:;:..__--.-----r---~......__---.----L--r---~--~--.....-----1 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000 6,500 7,000 Projected 3R25 Worst Case Burst Pressure (psi)
Serial No.24-154 Docket No.
50-423,
Page 28 of 31 Table 10: Probabilities of Burst and Leakage at (3*NOPD)
Axial ODSCC @TSPs Population POB at 3llP POL Full Bundle 2.19%
1.33%
SG Program Maximum 5%
5%
Allowable Hypothetical axially oriented ODSCC at dent/ ding locations is addressed herein principally because of recent operating experience at Seabrook which has increased industry focus on this mechanism. During the 3R22 outage, all ~ 2 Volt hot-leg dent/ dings and all ~ 5 Volt cold-leg/ U-bend dent/ dings were examined using the +Point' probe. No sec was identified at any dent/ding location.
The same fully probabilistic, multi-cycle OA analysis methodology described in the previous pages was used to evaluate this degradation mechanism. The simulation of axial ODSCC at dent/ dings was benchmarked to cause a detection as early as 3R16, when in fact no dent/ ding ODSCC has ever been detected including the current 3R22 outage. This approach ensures that the Weibull crack initiation function utilized in the analysis is conservative. The shape parameter was selected based upon the research documented in the EPRI PWR Generic Tube Degradation Predictions Reports and the scale parameter was selected to yield at least one detection during 3R16 and subsequent outages 3R18, 3R21, 3R22, and 3R25.
Upon initiation, each crack is assigned a length value, sampled from a suitable length distribution. The length distribution utilized in this evaluation is based upon the measured lengths of MP3 dents and dings. Because the length and length growth of sec in SG tubing is dominated by the extent of the residual stress field, it is assumed that the ultimate lengths of cracks that develop within dents/ dings will be limited by the lengths of the dents/ dings themselves. Therefore, no additional length growth was applied within the simulation.
The depth growth rate distribution utilized in this evaluation is the conservative growth rate, for dent/ ding cracks, based on the EPRI 600TT Feasibility Study for Multicycle Operation adjusted to the MP3 operating temperature (617°F).
The distributions of 3R25 worst-case degraded tube burst pressures resulting from this analysis is shown in Figure 8. This figure demonstrates that the lower 95/50 burst pressure (i.e., the 5th percentile), 7678 psi satisfies the SIPC limit of 4080 psi; therefore, it is concluded that axial ODSCC at dents/ dings will not cause the structural integrity performance criteria to be exceeded in any of the MP3 SGs prior to 3R25. The projected total upper 95/50 accident leakage (GPM) is zero; therefore, it is concluded that axial ODSCC at dents/ dings will not cause the accident-induced leakage performance criteria to be exceeded prior to 3R25. These conclusions are also presented below in Table 11 in terms of the probability of burst (POB) at 3LiP and the probability of leakage (POL) under accident conditions.
- E n,
.c e Serial No.24-154 Docket No.
50-423,
Page 29 of 31 Figure 8: 3R22 Worst Case Burst Pressure - Axial ODSCC @Dents/Dings 0.20 ~---------------------------.--------,
3R25 Min BP 0.15 I ' '
I '
I ' ' '
I I ' '
I
- a.
~ 0.10
.i::
~
- i E
- s u 0.05
- Lower 95/50: 7678 psi 1
/
I I,'
I /
13XNOPD: 4080 psi
-f*----
Probability: 0.05 I
/
I I
I I
I
'1
,/'
I I
~
I 0.00 -----
...a-----,---__,;o----,-------------
3,000 4,000 5,000 6,000 7,000 8,000 9,000 Projected 3R25 Worst Case Burst Pressure (psi)
Table 11: Probabilities of Burst and Leakage at (3*NOPD)
Axial ODSCC @Dents/Dings Population POB at 3LlP POL Full Bundle
< 0.005%
0.008%
SG Program Maximum 5%
5%
Allowable 10,000
- h. The primary to secondary LEAKAGE rate observed in each SG (if it is not practical to assign the LEAKAGE to an individual SG, the entire primary to secondary LEAKAGE should be conservatively assumed to be from one SG) during the cycle preceding the inspection which is the subject of the report, No primary to secondary SG leakage was reported during Cycle 22.
Serial No.24-154 Docket No.
50-423,
Page 30 of 31
- i. The calculated accident induced leakage rate from the portion of the tubes below 15.2 inches from the top of the tubesheet for the most limiting accident in the most limiting SG. In addition, if the calculated accident induced leakage rate from the most limiting accident is less than 2.49 times the maximum operational primary to secondary leakage rate, the report should describe how it was determined; For the purposes of the condition monitoring assessment, and in accordance with the permanent alternate repair criteria, the accident leakage attributed to degradation within the tubesheet below the H* dimension must be estimated by applying a factor of 2.49 to the operational leakage.
There was no recordable operational leakage during Cycle 22; therefore, the leakage from this degradation during a limiting accident would have been zero (i.e., 2.49 X 0).
- j. The results of monitoring for tube axial displacement (slippage). If slippage is discovered, the implications of the discovery and corrective action shall be provided.
Tube slippage monitoring was performed on all four SGs using the bobbin coil data during 3R22. There was no detection of slippage during the 3R22 examination.
t Positive direction of sign convention for reporting ind h:atlons Serial No.24-154 Docket No.
50-423,
Page 31 of 31 Figure - 9 Model F General Support Configuration AV3 AV4 AV6 Location of OSH 1=4=m:=::=:::;.===:i==.:==;;:;;;;-:::::==:!ti..... OSC Sign Convention 05H J:;:.:====::=:;:;======~ -
OS'C 04H O3H 02H OH-I TSH TEH ML
._ TSC
..--..--.--.,1,-:11-..&~~~~J -
TEC ChangQ (OSC + 2,00"')
T Positive dftedio n ofslgn conventioh fo, reporting lndlc.ations Acronyms MILLSTONE POWER STATION UNIT 3 Serial No.24-154 Docket No. 50-423 DOMINION ENERGY NUCLEAR CONNECTICUT, INC. (DNC)
Acronyms AVB Anti-Vibration Bar OVR BET Bottom of the Expansion Transition OXP BLG Bulge PIO C
Column PLG CL Cold Leg PLP DOH Ding or Dent Signal - Reviewed in PTE History PWR DOI Distorted Dent or Ding Indication PWSCC DDS Ding or Dent Signal - Non-Confirming w/RPC R
ONG Ding RAD ONT Dent Indication RBD ECT Eddy Current Test RIC EFPY Effective Full Power Years RRT EPRI Electric Power Research Institute S/N ETSS Examination Technique SAi Specification Sheet sec F/L Full Length SCI FAC Flow Accelerated Corrosion SG FOB Flow Distribution Baffle SLG FO Foreign Object SSI FOTS Foreign Object Tracking System SVI HL Hot Leg TEC IGA lntergranular Attack TEH INF Indication Not Found TFH INR Indication Not Reportable LPI Loose Part Indication TFS LPR Loose Part Removed LPS Loose Part Signal TSC MRPC Motorized Rotating Pancake Coil TSH NOD No Detectable Degradation TSP NOE Nondestructive Examination TTS NDF No Degradation Found TWO NEI Nuclear Energy Institute
%TW NQH Non-quantifiable Indication -
VOL Reviewed in History NQI Non-quantifiable Indication OA Operational Assessment ODSCC Outer Diameter Stress Corrosion Cracking Serial No.24-154 Docket No. 50-423, Page 1 of 1 Above Tubesheet Over Expansion Over Expansion Positive Identification Tube is plugged Possible Loose Part Partial Tubesheet Expansion Pressurized Water Reactor Primary Water Stress Corrosion Cracking Row Retest Analyst Discretion Retest - Bad Data Retest - Incomplete Retest - Restricted Tube Signal-to-Noise Ratio Single Axial Indication Stress Corrosion Cracking Single Circumferential Indication Steam Generator Sludge Secondary Side Inspection Single Volumetric Indication Tube End Cold Leg Tube End Hot Leg Tangential Flaw-Like Signal - Reviewed in History Tangential Flaw-Like Signal - Non-Confirming w/RPC Top of Tubesheet Cold Leg Top of Tubesheet Hot Leg Tube Support Plate Top of Tubesheet Through-Wall Depth Percent Through-Wall Volumetric Indication