ML22108A224

Steam Generator Tube Inspection Report for the Fall 2021 Refueling Outage

ML22108A224
Person / Time
Site:	Surry
Issue date:	04/14/2022
From:	Mladen F Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
22-059
Download: ML22108A224 (31)

Text

VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 APR 1 4 2022 United States Nuclear Regulatory Commission Serial No.22-059 Attention: Document Control Desk SS&L/MMT RO Washington, DC 20555-0001 Docket No. 50-281 License No. DPR 37 VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNIT 2 STEAM GENERATOR TUBE INSPECTION REPORT FOR THE FALL 2021 REFUELING OUTAGE Technical Specification 6.6.A.3 for Surry Power Station Units 1 and 2 requires the submittal of a Steam Generator Tube Inspection Report to the NRC within 180 days after Tavg exceeds 200°F following completion of an inspection performed in accordance with Technical Specification 6.4.Q, Steam Generator Program. Attached is the Surry Unit 2 report for the Fall 2021 refueling outage.

If you have any questions concerning this information, please contact Mr. Michael M.

True, Jr. at (757) 365-2446.

Very truly yours, Fred Mladen Site Vice President

Attachment:

Surry Unit 2 Steam Generator Tube Inspection Report for the Fall 2021 Refueling Outage Commitments made in this letter: None

Serial No.22-059 Docket No. 50-281 Page 2 of 2 cc: U.S. Nuclear Regulatory Commission Region II Marquis One Tower 245 Peachtree Center Ave" NE Suite 1200 Atlanta, Georgia 30303-1257 Mr. John Klos NRC Project Manager - Surry U.S. Nuclear Regulatory Commission One White Flint North Mail Stop 09 E-3 11555 Rockville Pike Rockville, Maryland 20852-2738 Mr. G. Edward Miller NRC Senior Project Manager - North Anna U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 09 E-3 11555 Rockville Pike Rockville, Maryland 20852-2738 NRC Senior Resident Inspector Surry Power Station Mr. Rusty R. Richardson Authorized Nuclear Inspector Surry Power Station

Serial No.22-059 Docket No. 50-281 ATTACHMENT 1 SURRY UNIT 2 STEAM GENERA TOR TUBE INSPECTION REPORT FOR THE FALL 2021 REFUELING OUTAGE VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION ENERGY VIRGINIA)

Serial No.22-059 Attachment 1 Docket No. 50-281 page 1 of 28 SURRY UNIT 2 STEAM GENERATOR TUBE INSPECTION REPORT FOR THE FALL 2021 REFUELING OUTAGE The following satisfies the Surry Power Station Technical Specification (TS) reporting requirement section 6.6.A.3. During the Surry Unit 2 Fall 2021 End-Of-Cycle 30 (EOC30) refueling outage, Steam Generator (SG) inspections were completed in accordance with TS 6.4.Q for all three SGs, designated as SG-A, SG-B, and SG-C. Unit 2 exceeded 200°F on November 27, 2021; therefore, this report is required to be submitted by May 26, 2022.

SG-A and SG-C were last inspected during the Fall 2018 refueling outage (EOC28) and had operated for 366.0 EFPM prior to that outage. SG-B was last inspected during the Spring 2017 refueling outage (EOC27) and had operated for 349.6 EFPM preceding that outage. At the time of this inspection, the Unit 2 SGs had operated for 398.4 EFPM since the first in-service inspection. Consequently, SGs A and C had operated for 32.4 EFPM since the last inspection of those SGs and SG-B had operated for 48.8 EFPM since that SG was last inspected. An inspection for SG-B was planned for the spring 2020 outage, but it was deferred to fall 2021 in accordance with License Amendment No. 299.

The three Surry Unit 2 steam generators are replacement Model 51 F lower assemblies (i.e.,

tube bundle, lower shell, and channel head) and primary moisture separator assemblies (F-type). They were replaced in 1980. The moisture separators were subsequently upgraded to support a core power up-rate implemented in 1995. The feedrings were replaced in 2011.

Each of the three SGs were fabricated with 3,342 Thermally Treated Alloy 600 tubing, with nominal 0.875" OD x 0.050" wall thickness. The seven broached quatrefoil support plates are fabricated from 405 Stainless Steel. Figure 5 contains a schematic depicting the general arrangement of the steam generators without dimensions. Figures 6 and 7 contain a photo of the Disk Stack and an illustration of its position in the Feedwater Regulating Valve respectively.

The Disk Stack provides an effective barrier against foreign objects in the feedwater entering the steam generators. However, it is believed that the legacy foreign material on the top of the tubesheet had been introduced into the steam generators from the previously mentioned maintenance activities performed in the steam drums. During the Fall 2021 outage, significant effort was expended on the removal of legacy foreign material located on the top of the tubesheet in all three SGs.

The Unit 2 steam generators have experienced no reportable primary to secondary leakage since the forced shutdown of June 1986 and operate with a nominal hot leg temperature of 604°F.

Each of the Surry Unit 2 SGs was screened to identify any low row indications of improper heat treatment. None were identified. All of the SGs were also screened for long row indications of improper heat treatment (-2 sigma tubes) and associated high residual stress. This evaluation identified 0, 2, and 14 tubes in SGs A, B, and C, respectively, which may have been improperly heat treated. Table 1 provides a listing of tubes that have been identified through screening as possibly containing high residual stress due to an improper heat treatment. These tubes were examined full length with array probes and closely scrutinized during the analysis process.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 2 of 28 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 EOC30 examination.

Table 1: Tubes with Potentially High Residual Stress SG Row Column No. Tubes A None 0 B 17 71 2

B 17 78 C 14 7 C 23 10 C 23 31 C 23 87 C 24 15 C 24 16 C 25 11 14 C 25 30 C 26 10 C 27 15 C 27 16 C 27 77 C 32 15 C 32 24 In the discussion below Bold Italicized wording represents TS verbiage and the required information is provided directly below each reporting requirement. A list of acronyms is contained in Table 12 at the end of this report.

A report shall be submitted within 180 days after Tavg exceeds 200°F following completion of an inspection performed in accordance with the Specification 6.4.Q, "Steam Generator (SG) Program." The report shall include:

a. The scope of inspections performed on each SG Primary Side The tubing in each SG was inspected with bobbin coil probes over their full length except for the Row 1 and 2 U-bends, which were examined with a +Point' rotating probe. An array probe examination was conducted on 100% of the tubes at the hot leg and cold leg tubesheets. The extent of the array probe tubesheet examinations was from the first support structure located above the tubesheet down to the H-star dimension.

Note that the permanent alternate repair criteria (PARC), Technical Specification (TS 6.4.Q),

eliminates the need to analyze the Surry SG tubing for degradation in the region below the H-star dimension which is 17.89 inches below the top of the tubesheet. It also eliminates the need to plug tubes if the only repairable degradation is located below the H-star dimension.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 3 of 28 All high residual stress (HRS) tubes in SGs B and C (SG-A does not have HRS tubes) were examined full length with both Bobbin and Array probes due to the increased susceptibility of Stress Corrosion Cracking.

In addition to the base scope, a preplanned special interest scope was developed for the EOC30 inspection, which includes a sample of previously identified dents, dings, manufacturing burnish marks, volumetric indications, and wear (excluding AVB wear). The only departure from the EOC28 preplanned special interest strategy and the preplanned EOC30 special interest scope was the sample plan for the inspection of dents/dings.

As a result of concerns for possible degradation at denUding locations, the special interest scope of dents/dings with a +Point' probe was increased significantly. The specific dent/ding scope performed during the EOC28 inspection included fifty percent of previously identified dents/dings >2 Volts located in hot-leg straight sections (TSH+0.00 to 07H+1.00"), plus any additional indications required to ensure that the five largest voltage dents/dings in hot-leg straight sections were included in the sample. Also, the five largest voltage dents/dings located between the cold-leg tubesheet and the straight section of the hot-leg, (between TSC+0.00 and 07H+1.01") were included in the preplanned scope. The specific dent/ding scope performed during the EOC30 inspection included 100% of all dents/dings 2: 2 Volts located in the hot leg straight section and 100% of all dents/dings 2: 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 Surry Power Station, the referenced dent signals do not represent the same phenomena as classical denting on older generation units caused by drilled carbon steel support plate corrosion damage. Since the Surry units 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 Surry units. 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.

The primary side work scope also included video / visual examinations (as-found / as-left) of all channel heads specifically including:

• All plugs

• Tube-to-tubesheet welds

Serial No.22-059 Attachment 1 Docket No. 50-281 page 4 of 28

• Stub runner and divider plate

• Stub runner to divider plate welds

• Stub runner to tubesheet clad weld

• Divider plate-to-channel head clad weld

• Tubesheet cladding

• Closure ring welds

• Entire bowl cladding with the bowl effectively dry All primary side visual examinations were completed satisfactorily with no degradation or anomalies reported.

Secondary Side During the EOC30 examination, the following secondary side activities were performed in all three SGs:

• Pre-lance raking of foreign material at the top of the tubesheet to improve cleanliness in the tie rod shadow zones

• Top of tubesheet water lancing

• Post-lancing visual examination of the tube bundle from the entire periphery

• Visual examination of historical foreign object-related locations

• Visual investigation of any accessible locations having eddy current signals potentially related to foreign objects, and removal of retrievable foreign objects.

• Visual examination of the following to assess material condition and cleanliness:

o All accessible steam drum components and structures including the feedrlng exterior o The upper tube bundle and 7th TSP via probe insertions through primary moisture separators o The primary separators to identify any potential FAG in the riser barrels, flow holes, and tangential nozzles similar to what has been seen in other Westinghouse SGs

b. Degradation mechanisms found During the EOC30 examination, anti-vibration bar (AVB) wear, tube support plate (TSP) wear, flow distribution baffle (FOB) wear, foreign object wear, and stress corrosion cracking (SCC) were detected during the SG tube examination.

Cracking of secondary separator perforated plate welds in SG-A were detected and repaired during the steam drum examination.

c. Nondestructive examination techniques utilized far each degradation mechanism The inspection program focused on the degradation mechanisms listed in Table 2 and utilized the referenced eddy current techniques.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 5 of 28 Table 2 - Inspection Method for Applicable Degradation Mechanism Degradation Classification Location Probe Type Mechanism Existing Wear Anti-Vibration Bars Bobbin - Detection and Sizing Bobbin and Array - Detection Existing OD Pitting Top-of-Tubesheet (TTS)

+Point' - Sizing Bobbin - Detection Existing Wear Tube Support Plate

+Point' - Sizing Tube Wear (Foreign Bobbin and Array - Detection Existing Freespan and TTS Objects) +Point' - Sizing Array - Detection Existing PWSCC Tubesheet Overexpansions (OXP)

+Point' - Sizing Existing PWSCC Tube Ends N/A*

Bobbin - Detection Existing Wear Flow Distribution Baffle (FOB)

+Point' - Sizing Bulges, Dents, Manufacturing Array - Detection Potential ODSCC, PWSCC Anomalies, and Above Tubesheet

+Point' - Sizing Overexpansions (OVR)

Tubesheet Crevice in Tubes With Potential ODSCC N/A**

NTE Potential Tube Slippage Within Tubesheet Bobbin - Detection Array - Detection Existing ODSCC, PWSCC Hot Leg TTS

+Point' - Sizing

+Point' - Detection and Potential ODSCC, PWSCC Row 1 and 2 U-bends Sizing Bobbin - Detection Potential ODSCC Freespan and Tube Supports

+Point' - Sizing Bobbin and Array - Detection Existing ODSCC, PWSCC High Residual Stress Tubes

+Point' - Sizing

• Inspection not required per technical specification alternate repair criteria

• • All tubes with no tubesheet expansion (NTE) have previously been plugged

d. Location, orientation (if linear), and measured sizes (if available) of service induced indications As stated in the (b) response above, anti-vibration bar (AVB) wear, tube support plate (TSP) wear, flow distribution baffle (FOB) wear, foreign object wear, and stress corrosion cracking (SCC) were detected during the EOC30 SG tube inspection.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 6 of 28 AVB Wear In total, 124 AVB wear indications in 86 tubes were identified among all three SGs during EOC30. Of these, 94 indications in 75 tubes were sized <20% TW. None of the identified flaws exceeded the Technical Specification plugging limit (40% TW) and none were plugged. The maximum reported depth was 33% TW. A listing of all 30 indications of AVB Wear .:: 20% TW is contained in Table 3.

Table 3: Surry 2 EOC30 Inspection Summary-AVB Wear Indications ~20% TW Wear Depth (%TW)

ETSS 96041.1 Amplitude SG Row Col AVB No. (Volts) Previous Current A 25 57 AV2 0.91 15 20 A 26 86 AV3 1.18 20 23 A 36 62 AV2 1.60 26 28 A 36 62 AV4 2.40 29 33 A 38 72 AV4 1.45 25 27 A 38 74 AV4 1.03 20 23 A 40 65 AV2 1.28 21 25 B 26 64 AV2 1.16 13 20 B 38 74 AV2 1.12 14 20 B 38 74 AV4 1.36 16 23 C 25 27 AV2 3.18 32 33 C 25 29 AV3 1.62 23 24 C 26 26 AV4 1.14 18 20 C 31 69 AV2 1.30 22 21 C 33 59 AV3 1.14 21 20 C 33 68 AV1 1.20 21 21 C 33 68 AV2 1.35 22 22 C 33 70 AV3 1.08 20 20 C 34 29 AV4 1.13 19 21 C 37 73 AV3 1.14 18 20 C 38 28 AV3 1.16 17 21 C 38 30 AV2 1.19 15 21 C 39 53 AV3 2.33 30 30 C 39 55 AV3 1.61 25 26 C 39 55 AV4 1.58 24 25 C 40 33 AV2 1.79 26 26 C 40 33 AV3 1.76 26 25 C 40 63 AV4 1.10 21 21

Serial No.22-059 Attachment 1 Docket No. 50-281 page 7 of 28 Wear Depth (% TW)

ETSS 96041.1 Amplitude SG Row Col AVB No. (Volts) Previous Current C 41 66 AV3 1.09 19 20 C 43 61 AV1 1.56 25 23 Non-AVB Wear Bobbin probe or array probe inspections of in-service tubes identified 67 indications of volumetric tube degradation not related to AVB wear, in 60 tubes among all three SGs. The measured flaw depths range from 5% TW to 35% TW. Sizing of these indications was performed with a +Point' rotating coil. Table 4 lists the 51 Non-AVB Wear indications that recorded wall losses ~ 20% TW. The sizing techniques used to determine the dimensions of the flaws are also identified in the table.

Sixty-five of the 67 indications were reported during previous inspection outages, meaning that two indications were newly reported during EOC30 (23%TW TSP wear in SG-B R10 C58, and 26% TW TSP wear in SG-B R42 C40). Review of historical ECT data for these locations confirmed that neither indication was previously detectible. None of the 65 repeat indications exhibited signal change indicative of wear growth.

Nine of the indications resulted from support structure wear (TSP or baffle plate) and all of the remaining 58 indications are attributed to foreign object wear, with no foreign object remaining in the vicinity of the wear indication.

Figure 1 through Figure 4 provide the 95/50 CM limit curves for flaws sized with ETSS 27901.1, 27902.1, 27905.1, and 96910.1 respectively. The CM curves represent the structural performance criteria derived by conservatively accounting for material property uncertainties, model uncertainties, and NOE depth sizing uncertainties. The uncertainties were combined using Monte Carlo techniques.

Because each flaw plotted in Figure 1 through Figure 4 lies below the CM limit curve, each flaw satisfies the structural integrity performance criterion.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 8 of 28 Table 4: Summary of Non-AVB Wear Volumetric Degradation Max Circ Foreign Depth Axial Length Length Initially Object In Situ Plugged &

SG Row Col Volts Location ETSS (3/4TW) (in) (in) Reported Cause Remaining? Tested? Stabilized?

0.12 TSC +0.62" 27901.1 21 0.33 0.42 2015 Foreign Object No No No A 4 37 0.20 TSC +1.5" 27901.1 26 0.36 0.37 2015 Foreign Object No No No A 11 45 0.18 TSH +0.98" 27901.1 24 0.30 0.37 2012 Foreign Object No No No A 15 16 0.18 TSH +0.25" 27901.1 24 0.22 0.34 2012 Foreign Object No No No A 17 16 0.21 TSH -0.10" 27901.1 26 0.31 0.45 2002 Foreign Object No No No A 18 16 0.18 TSH-0.12" 27901.1 24 0.30 0.42 2002 Foreign Object No No No A 33 27 0.16 TSC -0.04" 27901.1 23 0.25 0.37 2006 Foreign Object No No No A 42 52 0.11 TSC +0.18" 27901 .1 20 0.24 0.37 2009 Foreign Object No No No A 43 61 0.14 BPH +0.53" 27901.1 22 0.30 0.45 2009 Foreign Object No No No A 43 64 0.17 BPH +0.66" 27901.1 24 0.30 0.29 2009 Foreign Object No No No B 10 58 0.45 03H-0.66" 96910.1 23 0.34 0.37 2021 TSP Wear No No No 0.15 TSC + 0.01" 27901.1 22 0.17 0.31 2017 Foreign Object No No No B 18 81 0.11 TSC + 0.26" 27901.1 20 0.17 0.37 2017 Foreign Object No No No B 23 82 0.13 TSH- 0.18" 27901 .1 21 0.25 0.32 2003 Foreign Object No No No B 34 66 0.15 TSC + 0.18" 27901.1 23 0.28 0.42 2017 Foreign Object No No No B 36 26 0.76 TSC + 0.04" 27905.1 25 0.24 0.47 2008 Foreign Object No No No B 37 27 0.19 TSC- 0.01" 27901.1 25 0.28 0.34 2008 Foreign Object No No No B 42 40 0.56 03H-0.55" 96910.1 26 0.39 0.32 2021 TSP Wear No No No B 42 42 0.22 TSC-0.18" 27901.1 26 0.28 0.42 2014 Foreign Object No No No C 28 22 0.26 TSH +0.14" 27901.1 29 0.25 0.3\:1 2014 Foreign Object No No No C 28 23 0.21 TSH +0.55" 27901.1 26 0.19 0.47 2014 Foreign Object No No No

Serial No.22-059 Attachment 1 Docket No. 50-281 page 9 of 28 Max Circ Foreign Depth Axial Length Length Initially Object In Situ Plugged &

SG Row Col Volts Location ETSS (3/4lW) (in) (in) Reported Cause Remaining? Tested? Stabilized?

0.24 TSH +0.25" 27901.1 28 0.20 0.42 2014 Foreign Object No No No C 28 71 0.16 TSH +0.17" 27901.1 23 0.25 0.47 2009 Foreign Object No No No C 30 48 0.13 BPH +0.50" 27901 .1 21 0.19 0.42 2015 Foreign Object No No No C 34 18 0.12 TSH +1.00" 27901.1 20 0.38 0.37 2005 Foreign Object No No No C 34 20 0.23 TSH +0.92" 27901.1 27 0.31 0.26 2005 Foreign Object No No No C 34 74 0.23 TSH-0.03" 27901.1 27 0.31 0.42 2005 Foreign Object No No No C 35 19 0.22 TSH +0.29" 27901.1 27 0.31 0.42 2005 Foreign Object No No No C 35 22 0.23 TSH +1.04" 27901.1 27 0.33 0.47 2005 Foreign Object No No No C 35 30 0.37 TSH-0.08" 27901.1 35 0.25 0.42 2005 Foreign Object No No No C 36 32 0.13 BPH +0.65" 27901 .1 21 0.30 0.37 2015 Foreign Object No No No C 36 68 0.63 TSH-0.06" 27902.1 26 0.36 0.52 2005 Foreign Object No No No C 37 31 0.15 TSH +0.02" 27901.1 22 0.25 0.37 2011 Foreign Object No No No C 37 32 0.13 TSH +0.03" 27901.1 21 0.17 0.37 2011 Foreign Object No No No C 37 33 0.19 TSH +0.04" 27901.1 25 0.27 0.42 2011 Foreign Object No No No C 37 34 0.19 TSH +0.03" 27901.1 24 0.28 0.42 2009 Foreign Object No No No C 37 35 0,28 BPH +0.64" 27901.1 30 0.27 0.48 2005 Foreign Object No No No C 37 54 0.19 TSH +0.04" 27901.1 25 0.20 0.52 2005 Foreign Object No No No C 37 73 0.46 07C -0.67" 96910.1 22 0.46 0.43 2005 TSP Wear N/A No No C 38 32 0.18 BPH +0.63" 27901.1 24 0.28 0.37 2011 Foreign Object No No No C 38 53 0.15 TSH +0.04" 27901.1 23 0.19 0.63 2005 Foreign Object No No No 0.15 BPH +0.57" 27901 .1 22 0.19 0.42 2011 Foreign Object No No No C 39 32 0.16 BPH +0.60" 27901.1 23 0.21 0.42 2011 Foreign Object No No No C 39 34 0.18 BPH +0.63" 27901.1 24 0.30 0.40 2011 Foreign Object No No No C 40 34 0.13 BPH +0.65" 27901 .1 21 0.30 0.42 2011 Foreign Object No No No C 44 42 0.16 TSH -0.03" 27901.1 23 0.25 0.37 2005 Foreign Object No No No

Serial No.22-059 Attachment 1 Docket No. 50-281 page 10 of28 Max Circ Foreign Depth Axial Length Length Initially Object In Situ Plugged &

SG Row Col Volts Location ETSS (3/4TW) (in) (in) Reported Cause Remaining? Tested? Stabilized?

C 44 43 0.19 TSH +0.04" 27901.1 25 0.31 0.42 2005 Foreign Object No No No C 44 47 0.20 TSH-0.09" 27901.1 25 0.36 0.43 2005 Foreign Object No No No 0.16 TSH +0.16" 27901.1 21 0.20 0.42 2005 Foreign Object No No No C 45 43 0.19 TSH +0.13" 27901.1 24 0.31 0.42 2005 Foreign Object No No No C 45 47 0.11 TSH +0.01" 27901.1 20 0.30 0.42 2005 Foreign Object No No No

Serial No.22-059 Attachment 1 Docket No. 50-281 page 11 of 28 Stress Corrosion Cracking One circumferential PWSCC indication was identified at the hot leg top of tubesheet (TTS) in tube SG-C R6 C48 (TSH-0.25") during the EOC30 array probe examination. This indication was sized with a +Point' Probe. The maximum measured amplitude was 1.18 Volts. The maximum measured depth of the indication was 47% TW, the measured circumferential extent was 30 degrees, and the measured Percent Degraded Area (PDA) was 2.2.

One axial PWSCC indication was identified within the tubesheet in tube SG-B R21 C21 (TSH-0.95") during the EOC30 array probe examination. This indication was sized with a +Point' probe. The maximum measured amplitude was 0.29 Volts. The maximum measured depth of the indication was 66%TW, the measured length was 0.20 inches, the structurally equivalent depth was sized at 53.6%TW, and the structurally equivalent length was sized at 0.14 inches.

Foreign Objects As stated earlier, a significant effort was expended on the removal of legacy foreign objects from the secondary side of all three SGs during the EOC30 outage. It is believed that the legacy foreign material on the top of the tubesheet had been introduced into the SGs from the maintenance activities performed in the steam drums many years before.

In previous outages, multiple small pieces of wire had been detected, which had migrated into low flow areas forming localized entangled wire masses. These wire masses had been present in some of the SGs for more than 1O years without causing any tube wall degradation. The wires were evaluated and determined to be made of 304 stainless steel approximately 0.5" long and 0.012" in diameter. This is a diameter common for wire bristles associated with cleaning tools such as small wire brush wheels. Individually, these small wires don't present a threat to tube integrity because they lack the mass required to penetrate the tube wall and therefore considered to be benign.

During the EOC30 outage an enhanced tubesheet cleaning process was performed in all three steam generators to remove debris and legacy foreign objects. The as-left condition also provided a known baseline to positively identify any new foreign object intrusion during future operational cycles.

The foreign objects identified in Table 5 below include all foreign objects removed during the EOC30 FOSAR and water lancing activities and the foreign objects known to be remaining at the conclusion of the EOC30 outage.

Sludge removed during the water lance process was:

SG-A = 23 lbs.

SG-B = 12 lbs.

SG-C = 15 lbs.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 12 of 28 Table 5: Foreign Object Highlights SG-Item 2021 ECT Estimated

1. Description Affected Tubes Configuration Results Size Fixity 2021 Disposition During 2021 a legacy tube (adjacent to a piece offlex) and its associated bounding tubes were examined by ECT.

The only reported PLP was a 2012 piece of legacy PLP from 2012. No flexitallic gasket tube wear indications were R18-C46 embedded in A-1 Flexitallic Gasket PLP ~0.6" Fixed reported. FOSAR confirmed TSC +0.10 sludge formation that the object was still and fixed to embedded in the sludge tube/ tubesheet formation and affixed to the tube / tubesheet. At the next ISi continue to monitor the affected and bounding tubes using ECT and SSI.

During 2003 four tubes were plugged for a bolt like foreign object. During 2021, the tubes R21-C10, R22- bounding the four plugged C10 2003 bolt like tubes were examined by ECT.

object. Four Remains No PLP or tube wear B-1 Bolt Like Object R22-C11, R21- NOD 1/2" X 1.5" affected tubes in SG indications were reported.

C11 plugged FOSAR was not able to 02C+0.65 access the location. At the next ISi continue to monitor the bounding tubes using ECT.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 13 of 28 SG-Item 2021 ECT Estimated

1. Description Affected Tubes Configuration Results Size Fixity 2021 Disposition During 2021 an irregular shaped objected and a piece

~1.7" of wire was detected by 2021 irregular length FOSAR (pre-lance inspection)

R38-C47, R38- object and piece

~0.4" wide and removed from the SG.

C48 of wired Removed Irregular Object/ Subsequent ECT inspections B-2 removed by NOD ~0.1" thick by Piece of wire R37-C47 of the affected and bounding FOSAR during FOSAR TSC +0.10 tubes detected no PLP or tube pre-lance Wire wear indications. This item is inspection

~1" length considered closed out and no action is required at the next ISi.

During 2021 the ECT PLP R41-C44, R42- aligned with the location of the C44, legacy EWM. ECT reported C-1 2017 and 2018 Removed that no tube wear was Entangled Wire R41-C45, R42- ~16tubes and Entangled Wire PLP by detected. After lancing Mass (EWM) C45 by 2 tubes C-2 Mass (EWM) lancing FOSAR reported that no part R43-C46 was present. At the next ISi TSC +0.13 continue to monitor the PLP locations using ECT.

During 2021 the legacy sludge rock and disc-shaped object were both detected by ECT 2017 sludge R5-C88, R6-C88 and FOSAR. No tube wear rock and 2018-Sludge Rock/ Disc was detected. FOSAR C-3 R6-C89 disc shaped LPS ~0.4" Fixed Shaped Object confirmed that the rock/object TSC +0.00 object affixed to are still fixed in place. At the the tubesheet next ISi continue to monitor the affected and bounding tubes using ECT and SSI.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 14 of28 SG-Item 2021 ECT Estimated

1. Description Affected Tubes Configuration Results Size Fixity 2021 Disposition During 2021 the legacy wire (item #5 at R19-C57) was R37-C57, R38- moved by lancing to location 2017 C-4 Small wire/ C57 #4 (row 36). After the second Small wires I Removed

~3 tubes lancing, FOSAR did not detect and Entangled Wire R36-C56, R36- EWM LPM by by 2 tubes the presence of the wire or C-5 Mass (EWM) C57 embedded in lancing EWM. No tube wear was TSH +0.00 hard sludge detected. Item is considered closed out and no action is required at the next ISi.

During 2021 ECT detected PLPs on tubes (35-67, 35-66, R34-C66 2014 The bar 34-66). No tube wear was Bar I sludge R35-C66, R35- Bar I sludge spans tube detected. The PLPs result C-6 PLP Fixed formation C67 formation gap of from a legacy fixed part. At the TSH +0.26 ~0.4" next ISi continue to monitor the affected and bounding tubes using ECT and SSL During 2021 the legacy metal nut was detected by both ECT R28-C68, R28- and FOSAR. No tube wear C69 2009 metal nut 0.36" length was detected. FOSAR embedded in C-7 Metal Nut R29-C68, R29- PLP Fixed confirmed the metal nut is still hard deposit 0.25" depth C69 fixed in place. At the next ISi formations 0.36" width TSH +0.23 continue to monitor the affected and bounding tubes using ECT and SSI.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 15 of 28 SG-Item 2021 ECT Estimated

1. Description Affected Tubes Configuration Results Size Fixity 2021 Disposition Fixed During 2021 the majority of and the legacy EWM (loose) was R24-C63, R24- 2009 EWM of removed by lancing. The Loose C62 wires that in remaining part of the EWM is Entangled Wire 2018 was ~0.5" fixed to the TTS. No tube wear C-8 R29-C62, R29- LPM Loose Mass (EWM) pushed from diameter was detected. At the next ISi C63 removed row-24 to row- continue to monitor the TSH +0.00 29 by affected (R29-C62, R29-C63) lancing and bounding tubes using ECTand SSI.

During 2005 two tubes were 2005 metal plugged for FO wear (affected object wedged tubes). During 2021, the tubes between two bounding the affected tubes R31-C28 tubes that 56%TW ~0.61" were examined by ECT. No Removed Metal Object that caused tube 52%TW axial extent PLP or tube wear indications C-9 R32-C28 by caused tube Wear wear. The two depth with both were reported. FOSAR TSH +0.17 lancing affected tubes +Point' indications confirmed that the metal were object was no longer present.

subsequently Item is considered closed out plugged and no action is required at the next ISi.

During 2021 a wire like object was found by FOSAR (during 2021 pre-lance inspection) and R31-C48, R32- Wire like object Removed subsequently removed from C-10 Wire Like Object C48 detected by NDD ~1.25" by the SG. ECT reported no PLP FOSAR near FOSAR or tube wear indications. Item TSH +0.15 90-degree is considered closed out and hand hole no action is required at the next ISi.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 16 of 28 SG-Item 2021 ECT Estimated

1. Description Affected Tubes Configuration Results Size Fixity 2021 Disposition During 2021 a wire like object was found by FOSAR (during pre-lance inspection) and R36-C48, R37- 2021 Removed subsequently removed from C-11 Wire Like Object C48 Wire like object NOD ~1.5" by the SG. ECT reported no PLP detected by FOSAR or tube wear indications. Item TSH +0.00 FOSAR is considered closed out and no action is required at next ISi.

During 2021 multiple ECT PLP indications were R40-C51, R39- 2021 partial 1.38" investigated by FOSAR and C51 metallic nut length Removed revealed the presence of a detected by C-12 Partial Nut R39-C52, R40- PLP / LPM by partial metallic nut. The nut FOSAR during 0.10" depth C52 FOSAR was subsequently removed by post-lance 0.07" width TSH +0.20 FOSAR. Item is considered inspection closed out and no action is required at the next ISL During 2021 a EWM was identified during FOSAR and subsequently broken apart Removed and manually removed from R7-C49, R7-C50 2021 by the SG. Any remnants C-13 Entangled Wire NOD

~OS FOSAR remaining on the TTS were Mass (EWM) Entangled Wire diameter TSH +0.20 Mass (EWM) and removed by lancing. ECT lancing reported no PLP or tube wear indications. Item is considered closed out and no action is required at the next ISi.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 17 of 28 SG-Item 2021 ECT Estimated

1. Description Affected Tubes Configuration Results Size Fixity 2021 Disposition During 2021 multiple ECT PLPs were investigated by FOSAR and determined to originate from an EWM. The R31-C42, R31- mass was manually broken C43 2021 Removed Entangled Wire ~3 tubes apart and subsequently C-14 Entangled Wire PLP by Mass (EWM) R29-C42 by 2 tubes removed by lancing. ECT Mass (EWM) lancing TSH +0.83 reported no associated tube wear indications. Item is considered closed out and no action is required at the next ISi.

During 2021 FOSAR identified a EWM. FOSAR broke the mass apart for subsequent R36-C51, R35-removal by lancing. Some C51 remnants of the EWM still R34-C51, R36- 2021 Partially remain on the ITS but is not Entangled Wire C52 ~3 tubes C-15 Entangled Wire NOD Fixed in considered a threat to tube Mass (EWM) by 2 tubes R35-C52, R34- Mass (EWM) Place integrity. ECT reported no C52 associated PLP or tube wear indications. At the next ISi TSH +0.50 continue to monitor the affected and bounding tubes using ECT.

During 2021 a wire like object was found by FOSAR.

Subsequent removal attempts 2021 1.50" showed the wire to be R34-C51, R34-Wire like object length embedded in hard sludge at C-16 Embedded Wire C50 NOD Fixed embedded in 0.12" depth the ITS. ECT reported no TSH +0.25 hard sludge PLP or tube wear indications.

0.12" width At the next ISi continue to monitor the affected and bounding tubes using ECT.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 18 of28 SG-Item 2021 ECT Estimated

1. Description Affected Tubes Configuration Results Size Fixity 2021 Disposition During 2021 a bar-like object was identified during FOSAR R32-C45, R33- and subsequently removed.

C45 2021 2.50" Removed Hard Bar-Like length ECT reported a LPS and no C-17 Hard bar-like LPS by Object R33-C44 tube wear indications. Item is object 0.15" width FOSAR TSH +0.15 considered closed out and no action is required at the next ISi.

During 2021 a EWM was identified during FOSAR and subsequently broke apart and removed from the SG. Any R43-C56, R43- 2021 Removed remnants remaining on the Entangled Wire C55 ~0.5" C-18 Entangled Wire NOD by TTS were removed during Mass (EWM) diameter TSC +0.10 Mass (EWM) lancing lancing. ECT reported no PLP or tube wear indications. Item is considered closed out and no action is required at the next ISi.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 19 of 28 Table 6: Summary of Prior OA Validation Fall 2018, EOC28 Spring 2020, EOC29 Operational COVID Deferral Observed During Degradation Assessment Operational the Fall 2021 Outage Mechanism (SGsA & C) Assessment (SG B) (EOC30)

Maximum 44.1 Maximum depth of AVBWear Maximum 38.8 % TW

%TW 33% TW detected Maximum depth of 35%TW detected; no Volumetric Maximum 40.8 Maximum 41.5 %TW growth of previously Degradation %TW reported flaws was observed.

Circumferential Not detected or 37.1 PDA and 73.1 ODSCC at top No indications detected evaluated %TW maximum depth of tubesheet Circumferential 39 POAand 71 PWSCC 45.4 POA and 88 %TW One indication detected:

%TWmaximum tubesheet maximum depth 47% TW x 30°, 2.2 POA depth region Axial ODSCC Not detected or Lower 95/50 burst No indications detected at TSPs evaluated pressure: 5,546 psi One 0.29Volt indication Axial PWSCC detected; 53.6% TW struct Not detected or Lower 95/50 burst tubesheet depth x 0.14 in. struct evaluated pressure: 5,342 psi region length; Sf PC and AILPC satisfied No measurable leakage Operational Projected: <150 Projected: <150 GPO during Cycles 28, 29, or Leakage GPO 30

e. Number of tubes plugged during the inspection outage for each degradation mechanism One tube in SG-8 was plugged for an axial PWSCC indication and one tube in SG-C was stabilized and plugged for a circumferential PWSCC indication.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 20 of 28

f. The number and percentage of tubes plugged to date, and the effective plugging percentage in each steam generator.

Table 7 provides the plugging totals and percentages to date.

Table 7 - Tube Plugging Summary Steam Generator SG-A SG-B SG-C Total Prior to EOC-30 30 19 50 99 EOC-30 0 1 1 2 Total 30 20 51 101

% Plugged 0.9% 0.6% 1.5% 1.0%

Since no sleeving has been performed in the Surry Unit 2 steam generators, the effective plugging percentage is the same as the actual plugging percentage.

g. The results of condition monitoring, including the results of tube pulls and in-situ testing None of the tube degradation identified in Surry Unit 2 SGs during the EOC28 outage violated the structural integrity performance criteria; thereby providing reasonable assurance that none of these flaws would have leaked during a limiting design basis accident. Therefore, tube pulls and in-situ pressure testing were not necessary.

The Condition Monitoring (CM) Assessment for each detected degradation mechanism was determined using the methodology described below.

Table 8 - CM Methodology CM (Mechanism) Methodoloav Structural Limit Note AVBWear Mixed Arithmetic/Monte Carlo Structural Limit (64% TW) 1 Vol (Non AVB} Monte Carlo CM Curve 2 Gire PWSCC (TTS) Mixed Arithmetic/Monte Carlo Structural Limit (63.2 PDA) 1 Axial PWSCC (TS) +Point Voltaqe (0.29 Volts) In-situ GL Voltaaes (Table 4-7) 3 Notes;

1) For CM, three uncertainties must be considered (NOE, burst relationship, and material properties). The Mixed Arithmetic/Monte Carlo methodology accounts for these uncertainties as follows. The Arithmetic part accounts for NOE uncertainty by using the ETSS depth sizing regression equation together with a 95/50 value (of the ETSS standard deviation) to arrive at the limiting upper bound %TW value. The Monte Carlo part accounts for uncertainty, from burst relationship and material properties, for determining the structural limit. If the upper bound %TW value is less than the structural limit, CM is met.

2) The CM curve, itself, has built into it the three uncertainties using Monte Carlo methods.

Therefore, no arithmetic correction for NOE sizing is required since it's accounted for by the CM curve.

3) CM for Axial PWSCC (TS) was determined by comparing the flaw's +Point voltage to the values in Table 4-7 of the In-Situ Guidelines.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 21 of 28 AVB Wear A mIxe . d A rl*th met"Ic/M one t C aro I meth od o IOQV was use dfor CM 0 fAVB wear.

Degradation Mechanism Maximum 95%/50% Upper CM Limit Depth (wear) Depth Bound Depth AVB Wear 33% 39.7% 64%

Since this upper bound estimate does not exceed the conservative structural limit of 64% TW, it is concluded that none of the AVB wear flaws exceeded the structural limit. Note that the 64% TW structural limit was developed under the guidance of Regulatory Guide 1.121 which considers both pressure and non-pressure loads.

Volumetric (Non-AVB Wear)

As indicated above, a Monte Carlo methodology was used for CM of the volumetric indications not attributed to AVB wear. Figure 1 through Figure 4 provide the 95/50 CM limit curves for flaws sized with ETSS 27901 .1, 27902 .1, 27905.1, and 96910 .1 respectively.

Figure 1: CM Curve for Flaws Sized w/ETSS 27901.1 - Model: Axial Thinning w/Limited Circumferential Extent 100 ..---.-- - - - - - - - - - - - - - - - - - - - - - - - - - ,

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Serial No.22-059 Attachment 1 Docket No. 50-281 page 22 of 28 Figure 2: CM Curve for Flaws Sized w/ETSS 27902.1 - Model: Axial Thinning w/Limited Circumferential Extent 100 ..----.*.- , --------------------------,

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Figure 3: CM Curve for Flaws Sized w/ETSS 27905.1 - Model: Axial Thinning w/Limited Circumferential Extent 100 ..----.-- - - - - - - - - - - - - - - - - - - - - - - - - - ,

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Serial No.22-059 Attachment 1 Docket No. 50-281 page 23 of 28 Figure 4: CM Curve for Flaws Sized w/ ETSS 96910.1 - Model: Axial Thinning w/Limited Circumferential Extent 100 ~ ~ - - - - - - -- -- - - - - - - - - - - - - - ~

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Stress Corrosion Cracking The circumferential PWSCC indication in was sized using ETSS 96701.1. The ETSS 96701.1 PDA uncertainty parameters are applied to determine the upper 95/50 PDA as follows:

ETSS 96701.1 PDA uncertainty parameters:

• Slope= 1.01

• Intercept= 8.55

• StdErr = 7.53 Upper 95/50 = (EOC30 PDA)(Slope)+(intercept)+(1.645)(StdErr)

Upper 95/50 = (2 .2 PDA)(1.01 )+(8.55)+(1.645)(7.53)

Upper 95/50 = 23 PDA Since the upper 95/50 PDA (23 PDA) does not exceed the conservative structural limit of 63.2 PDA, it is concluded that the circumferential PWSCC indication satisfied the SI PC.

Tube SGC R6 C48 was stabilized and plugged .

The axial PWSCC indication was sized using ETSS 96703.1 and the maximum measured amplitude was 0.29 Volts. CM for this indication was determined by comparing the flaw's

+Point voltage to the values provided in the In-Situ Guidelines.

Serial No.22-059 Attachment 1 Docket No. 50-281 page 24 of 28 Table 9: In-Situ Screening Values for Axial PWSCC Values SIPC 0.5 Volts AILPC Threshold 2.5 Volts Since the maximum measured +Point' signal amplitude (0.29 Volts) does not exceed the SIPC value (0.5 Volts) and does not exceed the AILPC threshold (2.5 Volts), it is concluded that the axial PWSCC indication satisfied both the SIPC and AILPC requirements.

Table 10 - OA Methodology OA (Mechanism) Methodoloav Structural Limit Note AVB Wear Mixed Arithmetic/Monte Carlo Structural Limit (64% TW) 1 FO Wear Plant Ooeratina Historv TSP/FOB Wear Mixed Arithmetic/Monte Carlo Structural Limit (56.6% TW) 1 Circ PWSCC Fully Probabilistic Multi-Cycle OA Lower 95/50 Burst Pressure> 3t.P 2 (TTSffS)

Axial PWSCC Fully Probabilistic Multi-Cycle OA Lower 95/50 Burst Pressure > 36P 2 (TTSffS)

Circ ODSCC Fully Probabilistic Multi-Cycle OA Lower 95/50 Burst Pressure > 3t.P 2 (TTS)

Axial ODSCC Fully Probabilistic Multi-Cycle OA Lower 95/50 Burst Pressure > 3t.P 2 (TSPs)

Axial ODSCC Fully Probabilistic Multi-Cycle OA Lower 95/50 Burst Pressure > 3LiP 2 (DNT/DNG)

1) For OA (plug on NOE sizing), four uncertainties must be considered (NOE, growth, burst relationship, and material properties). The Mixed Arithmetic/Monte Carlo methodology accounts for the four uncertainties as follows. The Arithmetic part accounts for NOE uncertainty by using the ETSS depth sizing regression equation together with a 95/50 value (of the ETSS standard deviation) to arrive at the limiting BOC %TW value. The limiting BOC % TW value is adjusted upward for growth allowance/uncertainty (to arrive at the EOG %TW value) and compared to the structural limit. The structural limit has been adjusted for burst relationship and material properties uncertainties using Monte Carlo methods. If the EOG %TW value is less than the structural limit, OA is projected to be met.

2) For the Fully Probabilistic Multi-Cycle OA, the lower 95/50 burst pressure must be greater than three times the primary-to-secondary differential pressure (3.1P).

Serial No.22-059 Attachment 1 Docket No. 50-281 page 25 of 28 Table 11 - OA Projected Condition During EOC33*

Structural Integrity Accident Induced Performance Criteria Leakage Performance Degradation Mechanism Criteria EOC33 EOC33 Limit Projection Limit Projection AVB Wear 64% 48.1%TW 470 GPO Zero Maximum Depth Leakaqe Foreign Object Wear 72% 35%TW 470 GPO Zero Maximum Depth Leakaqe TSP/FOB Wear 56.6% 52.8%TW 470 GPO Zero Maximum Depth Leakaqe Pittinq Dormant. No pro*ected pittinq.

Circumferential PWSCC within 4470 psi 7502 psi 470 GPO Zero tubesheet expansion Leakaqe Circumferential ODSCC @ 4470 psi 7364 psi 470 GPO Zero TTS Leakage Axial PWSCC @ TTS 4470 psi 4605 psi 470 GPO Zero Leakaqe Axial ODSCC @ TSPs 4470 psi 5502 psi 470 GPO Zero Leakage Axial ODSCC @ (DNT/DNG) 4470 psi 4933 psi 470 GPO Zero Leakage

• Although the Operational Assessment is projected to EOC33, an inspection is required to be performed during EOC31 due to the detection of stress corrosion cracking during EOC30.

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, Routine primary-to-secondary leak monitoring is conducted in accordance with station procedures. During the cycle preceding EOC30, no measurable primary-to-secondary leakage was observed in any Unit 2 SG.

i. The calculated accident induced LEAKAGE rate from the portion of the tubes below 17.89 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 Jess than 1.80 times the maximum operational primary to secondary LEAKAGE rate, the report should describe how it was determined, The permanent alternate repair criteria (PARC) requires that the component of operational leakage from the prior cycle from below the H-star distance be multiplied by a factor of 1.8 and added to the total accident leakage from any other source and compared to the allowable accident induced leakage limit. Since there is reasonable assurance that no tube degradation identified during this outage would have resulted in leakage during an accident, the contribution

Serial No.22-059 Attachment 1 Docket No. 50-281 page 26 of 28 to accident leakage from other sources is zero. Assuming that the prior cycle operational leakage is <1 GPO originated from below the H-star distance and multiplying this leakage by a factor of 1.8 as required by the PARC, yields an accident induced leakage value of <1.8 GPO.

This value is well below the 470 GPO limit for the limiting SG and provides reasonable assurance that the accident induced leakage performance criteria would not have been exceeded during a limiting design basis accident.

j. The results of the monitoring for tube axial displacement (slippage), If slippage is discovered, the implications of the discovery and corrective action shall be provided.

No indications of tube slippage were identified during the evaluation of bobbin probe examination data from any SG during EOC30.

Table 12 -Acronyms AILPC Accident Induced Leakage Performance Criteria NOD No Degradation Detected ARC Alternate Repair Criteria NOPD Normal Operating Pressure Differential AVB Anti-Vibration Bar NTE No Tube Expansion BLG Bulge OA Operational Assessment BOC Beginning Of Cycle OD Outside Diameter BPC Baffle Plate Cold ODSCC Outer Diameter Stress Corrosion Cracking BPH Baffle Plate Hot OVR Over Roll CM Condition Monitoring Assessment OXP Over Expansion DNG Ding PARC Permanent Alternate Repair Criteria DNT Dent PDA Percent Degraded Area ECT Eddy Current Test PLP Possible Loose Part EFPM Effective Full Power Months POD Probability Of Detection EOC End Of Cycle PWSCC Primary Water Stress Corrosion Cracking ETSS Examination Technique Specification Sheet sec Stress Corrosion Cracking EWM Entangled wire mass SG Steam Generator FAC Flow Assisted Corrosion SIPC Structural Integrity Performance Criteria FDB Flow Distribution Baffle SST Secondary Side Inspection FO Foreign Object TS Technical Specification FOSAR Foreign Object Search And Retrieval TSC Tube Sheet Cold GPD Gallons Per Day TSH Tube Sheet Hot HRS High Residual Stress TSP Tube Support Plate ISI In-Service Inspection TIS Top ofTubesheet LPM Loose Part Monitoring TW Through Wall LPS Loose Part Signal VOL Volumetric MBM Manufacturing Burnish Mark WAR Wear

Serial No.22-059 Attachment 1 Docket No. 50-281 page 27 of 28 Figure 5 - General Arrangement

Serial No.22-059 Attachment 1 Docket No. 50-281 page 28 of 28

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