ULNRC-06019, Response to Request for Additional Information Set 25 on License Renewal Application

Response to Request for Additional Information Set 25 on License Renewal Application

ML13217A074
Person / Time
Site:	Callaway
Issue date:	08/02/2013
From:	Ameren Missouri
To:	Office of Nuclear Reactor Regulation
Shared Package
ML13217A084	List: ML13217A073 ULNRC-06019, Response to RAI Set 25 Amendment 25 to LRA ULNRC-06019, Response to Request for Additional Information Set 25 on License Renewal Application
References
ULNRC-06019
Download: ML13217A074 (35)

Text

ULNRC-06019 August 2, 2013 Page 1 of 4 CALLAWAY PLANT UNIT 1 LICENSE RENEWAL APPLICATION REQUEST FOR ADDITIONAL INFORMATION (RAI) Set #25 RESPONSE

ULNRC-06019 August 2, 2013 Page 2 of 4 RAI B2.1.20-2

Background:

License renewal application (LRA) Section B2.1.20 stated that there were 19 Class 1 small-bore socket welds in the population of American Society of Mechanical Engineers (ASME) Code Class 1 piping less than 4 inches and greater than or equal to 1-inch nominal pipe size. During the staff audit of the aging management programs (AMPs) the applicant stated that a recount, subsequent to its December 15, 2011, LRA submission, indicated that there were 23 Class 1 small-bore socket welds within the scope of the One-Time Inspection of ASME Code Class 1 Small-Bore Piping Program. By letter dated July 18, 2012, the staff issued request for additional information (RAI) B2.1.20-1 requesting that the applicant verify the total population of ASME Code Class 1 socket welds within the scope of the AMP. In its response dated August 21, 2012, the applicant stated that there are 77 small-bore socket welds in the scope of the AMP. In a telephone conference call held on April 11, 2013, the staff requested additional clarification from the applicant to explain the reasons for the large discrepancy between the different counting results for the number of socket welds, and whether any errors in the counting process have been corrected.

Issue:

By letter dated April 15, 2013, the applicant supplemented its response to RAI B2.1.20-1. The supplemental response provided an explanation of how the error counting the number of socket welds occurred. In its response the applicant stated that the list of socket welds was developed from its Inservice Inspection (lSI) database, using the fields for ASME Category and Item Number. The applicant also stated the error occurred because some small-bore socket welds are exempt from ASME Section XI lSI volumetric and surface examinations and therefore, were never assigned any category and Item Numbers. The staff noted that a similar error could have also occurred when counting in-scope items for other AMPs in the LRA.

Request:

State whether the issue was entered in the Corrective Action Program, and provide the basis to justify that there is adequate assurance that other programs within the LRA are not subject to similar errors or omissions. Otherwise justify why a similar error could not, and did not occur elsewhere in the LRA.

Callaway Response The reporting of the incorrect number of ASME Class 1 small-bore socket welds in the as-submitted Callaway License Renewal Application (LRA) was entered into the Corrective Action Program as an adverse condition.

As part of the evaluation of the adverse condition, an extent of condition review was performed.

The original error was introduced during the process of developing a sample population (i.e.,

counting in-scope items) for the One-Time Inspection of ASME Code Class 1 Small-Bore Piping aging management program (AMP). Therefore, the extent of condition for the error was determined to be all instances where sample population numbers are cited in the LRA. To identify all instances, the as-submitted LRA and all responses to NRC Requests for Additional Information (RAIs) pertaining to the safety review of the LRA were electronically searched for mention of sampl (this spelling was specifically used to ensure that occurrences of the words

ULNRC-06019 August 2, 2013 Page 3 of 4 sample and sampling were identified) and population. Through this search, only two instances were identified where a sample population was developed in support of an AMP and cited in the LRA. Both instances are found within the One-Time Inspection of ASME Code Class 1 Small-Bore Piping AMP. Within that AMP, Callaway provided both the number of small-bore socket welds and the number of small-bore butt welds.

LRA Appendix A1.20 and Appendix B2.1.20 state, There are 77 Class 1 small-bore socket welds in the population of ASME Code Class 1 piping less than NPS 4 and greater than or equal to NPS 1 at Callaway. The number of socket welds was reviewed for accuracy. The number of Class 1 small-bore socket welds less than NPS 4 and greater than or equal to NPS 1 was confirmed to be 80. This minor change is the result of two one-inch Class 1 socket welds and a two-inch Class 1 socket weld that were identified through independent drawing reviews.

This constitutes a 4% change from the previous value and does not impact the examination population of 8 socket welds.

In addition, LRA Section B2.1.20 states, There are 340 Class 1 small-bore butt welds less than NPS 4 and greater than or equal to NPS 1 at Callaway. At least 25 butt welds will be included in the examination population. The number of butt welds was reviewed for accuracy. The number of Class 1 small-bore butt welds less than NPS 4 and greater than or equal to NPS 1 was confirmed to be 343. This minor change is the result of several one-inch Class 1 butt welds that were identified through drawing reviews and adjustments resulting from the original miscount of socket welds. This constitutes a 1% change from the original value and does not impact the examination population of 25 butt welds.

Callaway is dedicated to continuously improving the quality of the License Renewal Application.

Through ongoing review and critique of the application and associated documentation, questions arise that may result in corrections to the application. An example of this questioning attitude and continuous improvement is contained within Amendment 25. Callaway recently identified that the LRA states that the Essential Service Water (ESW) pump casing is exposed to a plant indoor air environment; however, the LRA did not state that the suction bell of the ESW pump casing is also submerged in a raw water environment. The occurrence of this error was entered into the Corrective Action Program (CAP) and the error was reviewed for extent of condition and impact on the LRA. The extent of condition review revealed that corrections were also needed to address submerged fire water system sump pump casings, and supports for the diesel fuel oil transfer pumps and piping that are submerged in the diesel fuel oil storage tanks.

An LRA amendment was prepared and the corrected information was reviewed by the Strategic Teaming and Resource Sharing (STARS) and Callaway License Renewal project groups and individual SMEs.

The Callaway LRA and all RAI responses and/or amendments are subjected to a thorough review process that includes originator and verification reviews by the STARS and Callaway License Renewal project groups, and concurrence reviews by individual Subject Matter Experts (SMEs). To limit the possibility of introducing a new error, all changes to the LRA are reviewed to determine if they impact related content elsewhere in the application. If an error is identified, the CAP process is followed. As evidenced by the limited occurrences of errors, the process by which Callaway prepares and reviews the LRA, RAI responses, and LRA amendments has been effective in assuring the accuracy and completeness of Callaway's documentation. In the event that an error or omission in docketed information is identified, the LRA and supporting documents are revised and the application and/or RAI responses are amended as needed. In

ULNRC-06019 August 2, 2013 Page 4 of 4 accordance with 10 CFR 54.13, the NRC is notified of an error or omission as part of the application and/or RAI response amendment process.

LRA Appendix A1.20 and Appendix B2.1.20 have been revised as shown in Amendment 25 in to update the confirmed number of Class 1 small-bore butt welds less than NPS 4 and greater than or equal to NPS 1 and Class 1 small-bore socket welds less than NPS 4 and greater than or equal to NPS 1.

Additionally, LRA Table 3.3.2-4, Table 3.3.2-20, Section 3.5.2.1.12, and Table 3.5.2-12 have been revised as shown in Amendment 25 in Enclosure 2 to correctly identify those components in the ESW, fire protection and fuel oil systems that are exposed to a submerged external environment.

Corresponding Amendment Changes Refer to the Enclosure 2 Summary Table "Amendment 25, LRA Changes for a description of LRA changes with this response.

ULNRC-06019 August 2, 2013 Page 1 of 31 Amendment 25, LRA Changes Summary Table Affected LRA Section LRA Page(s)

Table 2.1-2 2.1-22 Section 2.1.5.7 2.1-23 Table 3.1-1 3.1-50 Table 3.2-1 3.2-33 Section 3.3.2.1.4 3.3-8 Table 3.3-1 3.3.81 Table 3.3.2-4 3.3-95, 3.3-96, and 3.3-99 Table 3.3.2-20 3.3-210 and 3.3-216 Table 3.4-1 3.4-31 Section 3.5.2.1.12 3.5-17 and 3.5-18 Table 3.5.2-12 3.5-157, 3.5-160, 3.5-161, and 3.5-163 Table 4.3-6 4.3-35 Table 4.3-7 4.3-36 Section A1.10 A-6 Section A1.20 A-11 and A-12 Section A2.1 A-21 Section B2.1.7 B-31, B-32, and B-33 Section B2.1.10 B-41 through B-45 Section B2.1.20 B-72, B-73, and B-74

ULNRC-06019 August 2, 2013 Page 2 of 31 Callaway Plant License Renewal Application Amendment 25 Revised to indicate that LR-ISG-2012-01 has been issued.

Table 2.1-2, NRC Interim Staff Guidance Associated with License Renewal, (Page 2.1-

22) is revised as follows (new text underlined and deleted text shown in strikethrough):

Table 2.1-2 NRC Interim Staff Guidance Associated with License Renewal Issue Number Purpose Discussion Status LR-ISG-2006-03 Staff Guidance for Preparing Severe Accident Mitigation Alternatives (SAMA) Analyses The staff has issued LR-ISG-2006-03.

LR-ISG-2011-01 Aging Management of Stainless Steel Structures and Components in Treated Borated Water The staff has issued LRISG-2011-01.

LR-ISG-2011-02 Aging Management Program for Steam Generators The staff has issued LR-ISG-2011-02.

LR-ISG-2011-03 Aging Management Program for Buried and Underground Piping and Tanks The staff has issued LR-ISG-2011-03 LR-ISG-2011-04 Updated Aging Management Criteria for Reactor Vessel Internal Components of Pressurized Water Reactors This ISG has been issued in draft for public comment.

LR-ISG-2011-05 Ongoing Review of Operating Experience The staff has issued LRISG-2011-05.

LR-ISG-2012-01 Wall Thinning Due to Erosion Mechanisms This ISG has been issued in draft for public comment. The staff has issued LR-ISG-2012-01.

ULNRC-06019 August 2, 2013 Page 3 of 31 Callaway Plant License Renewal Application Amendment 25 Revised the discussion of LR-ISG-2012-01 to indicate that it is final, and to provide the location where wall thinning due to erosion mechanisms is discussed.

Section 2.1.5.7, (LR-ISG-2012-01) Wall Thinning Due to Erosion Mechanisms, (Page 2.1-23) is revised as follows (new text underlined and deleted text shown in strikethrough):

2.1.5.7 (LR-ISG-2012-01) Wall Thinning Due to Erosion Mechanisms This LR-ISG was issued in draft for public comment as final and is applicable to Callaway.

Wall thinning due to erosion mechanisms is discussed in B2.1.7, Flow-Accelerated Corrosion, and B2.1.10, Open-Cycle Cooling Water System.

ULNRC-06019 August 2, 2013 Page 4 of 31 Callaway Plant License Renewal Application Amendment 25 Changes made to incorporate LR-ISG-2012-01.

Table 3.1-1, Summary of Aging Management Programs in Chapter IV of NUREG-1801 for Reactor Vessel, Internals, and Reactor Coolant System, (Page 3.1-50) is revised as follows (new text underlined):

Table 3.1-1 Summary of Aging Management Programs in Chapter IV of NUREG-1801 for Reactor Vessel, Internals, and Reactor Coolant System Item Number Component Type Aging Effect / Mechanism Aging Management Program Further Evaluation Recommended Discussion 3.1.1.110 Not Applicable - BWR only

ULNRC-06019 August 2, 2013 Page 5 of 31 Callaway Plant License Renewal Application Amendment 25 Changes made to incorporate LR-ISG-2012-01.

Table 3.2-1, Summary of Aging Management Programs in Chapter V of NUREG-1801 for Engineered Safety Features, (Page 3.2-33) is revised as follows (new text underlined):

Table 3.2-1 Summary of Aging Management Programs in Chapter V of NUREG-1801 for Engineered Safety Features Item Number Component Type Aging Effect / Mechanism Aging Management Program Further Evaluation Recommended Discussion 3.2.1.065 Any material, piping, piping components, and piping elements exposed to treated water, treated water (borated)

Wall thinning due to erosion Flow-Accelerated Corrosion (B2.1.7)

No Not applicable. Callaway has not experienced wall thinning due to erosion in any Engineered Safety Features systems.

ULNRC-06019 August 2, 2013 Page 6 of 31 Callaway Plant License Renewal Application Amendment 25 The following change was made to add wall thinning as an aging effect requiring management for the essential service water system.

Section 3.3.2.1.4 (Page 3.3-8) is revised as follows (new text underlined):

3.3.2.1.4 Essential Service Water System Aging Effects Requiring Management The following essential service water system aging effects require management:

Cracking and changes in material properties Cracking, blistering, change in color Loss of material Loss of preload Wall thinning

ULNRC-06019 August 2, 2013 Page 7 of 31 Callaway Plant License Renewal Application Amendment 25 Changes made to incorporate LR-ISG-2012-01.

Table 3.3-1, Summary of Aging Management Programs in Chapter VII of NUREG-1801 for Auxiliary Systems, (Page 3.3-81) is revised as follows (new text underlined):

Table 3.3-1 Summary of Aging Management Programs in Chapter VII of NUREG-1801 for Auxiliary Systems Item Number Component Type Aging Effect / Mechanism Aging Management Program Further Evaluation Recommended Discussion 3.3.1.126 Any material, piping, piping components, and piping elements exposed to treated water, treated water (borated), raw water Wall thinning due to erosion Flow-Accelerated Corrosion (B2.1.7)

No Consistent with NUREG-1801 for material, environment, and aging effect, but a different aging management program for raw water systems Open-Cycle Cooling Water System (B2.1.10) is credited.

ULNRC-06019 August 2, 2013 Page 8 of 31 Callaway Plant License Renewal Application Amendment 25 Changes made to incorporate LR-ISG-2012-01 and to add an external environment of raw water for the Essential Service Water pumps.

Table 3.3.2-4 (Page 3.3-95, 3.3-96 and 3.3-99) is revised as follows (new text underlined):

Table 3.3.2-4 Auxiliary Systems - Summary of Aging Management Evaluation - Essential Service Water System Component Type Intended Function Material Environment Aging Effect Requiring Management Aging Management Program NUREG-1801 Item Table 1 Item Notes Piping LBS, PB, SIA Carbon Steel Raw Water (Int)

Wall thinning Open-Cycle Cooling Water System (B2.1.10)

VII.C1.A-409 3.3.1.126 E, 5 Pump PB Stainless Steel Raw Water (Ext)

Loss of material Open-Cycle Cooling Water System (B2.1.10)

VII.C1.A-54 3.3.1.040 A

Plant Specific Notes:

1 External Surfaces Monitoring of Mechanical Components program (B2.1.21) is used instead of Open Cycle Cooling Water program (B2.1.10) to manage the aging of the external surfaces of nonsafety-related components exposed to raw water.

2 HDPE piping is in an underground vault and potentially exposed to groundwater.

3 HDPE components in a plant indoor air environment are not exposed to an aggressive chemical environment that would concentrate contaminants and degrade HDPE chemical and mechanical properties. HDPE is not exposed to ozone, ionizing radiation or a UV source (sunlight or fluorescent light) that would result in aging. Operating temperatures do not exceed 140°F. HDPE components in a plant indoor air environment have no aging effects requiring aging management.

4 This TLAA is applicable to the high-density polyethylene (HDPE) piping. Section 4.7.7 describes the evaluation of this TLAA for the replacement ESW piping.

5.

Open-Cycle Cooling Water System program (B2.1.10) is used instead of Flow-Accelerated Corrosion program (B2.1.7) to manage wall thinning due to erosion of carbon steel piping exposed to raw water.

ULNRC-06019 August 2, 2013 Page 9 of 31 Callaway Plant License Renewal Application Amendment 25 Changes made to add an external environment of raw water for the Fire Protection sump pumps and valve pit pump.

Table 3.3.2-20 (Page 3.3-210 and 3.3-216) is revised as follows (new text underlined):

Table 3.3.2-20 Auxiliary Systems - Summary of Aging Management Evaluation - Fire Protection System Component Type Intended Function Material Environment Aging Effect Requiring Management Aging Management Program NUREG-1801 Item Table 1 Item Notes Pump PB Cast Iron (Gray Cast Iron)

Raw Water (Ext)

Loss of Material Selective Leaching (B2.1.19)

VII.G.A-51 3.3.1.072 B

Pump PB Cast Iron (Gray Cast Iron)

Raw Water (Ext)

Loss of material External Surfaces Monitoring of Mechanical Components (B2.1.21)

VII.G.A-33 3.3.1.064 E, 3 Notes for Table 3.3.2-20:

Standard Notes:

A Consistent with NUREG-1801 item for component, material, environment, and aging effect. AMP is consistent with NUREG-1801 AMP.

B Consistent with NUREG-1801 item for component, material, environment, and aging effect. AMP takes some exceptions to NUREG-1801 AMP.

C Component is different, but consistent with NUREG-1801 item for material, environment, and aging effect. AMP is consistent with NUREG-1801 AMP.

D Component is different, but consistent with NUREG-1801 item for material, environment, and aging effect. AMP takes some exceptions to NUREG-1801 AMP.

E Consistent with NUREG-1801 for material, environment, and aging effect, but a different aging management program is credited or NUREG-1801 identifies a plant-specific aging management program.

G Environment not in NUREG-1801 for this component and material.

ULNRC-06019 August 2, 2013 Page 10 of 31 Plant Specific Notes:

1 The fire water storage tanks rest on a sand cushion surrounded by a reinforced concrete ring beam.

2 PVC in a wastewater environment is unaffected by water, concentrated alkalies, nonoxidizing acids, oils, ozone, or humidity changes.

PVC in a waste water environment is not exposed to direct sunlight or ionizing radiation. Therefore PVC in a wastewater environment has no aging effect.

3.

The external surface of these pumps will be managed by the External Surfaces Monitoring of Mechanical Components program (B2.1.21).

ULNRC-06019 August 2, 2013 Page 11 of 31 Callaway Plant License Renewal Application Amendment 25 Changes made to incorporate LR-ISG-2012-01.

Table 3.4-1, Summary of Aging Management Programs in Chapter VIII of NUREG-1801 for Steam and Power Conversion Systems, (Page 3.4-31) is revised as follows (new text underlined):

Table 3.4-1 Summary of Aging Management Programs in Chapter VIII of NUREG-1801 for Steam and Power Conversion System Item Number Component Type Aging Effect / Mechanism Aging Management Program Further Evaluation Recommended Discussion 3.4.1.060 Any material, piping, piping components, and piping elements exposed to treated water Wall thinning due to erosion Flow-Accelerated Corrosion (B2.1.7)

No Not applicable. Callaway has not experienced wall thinning due to erosion in any Steam and Power Conversion System within the scope of License Renewal.

ULNRC-06019 August 2, 2013 Page 12 of 31 Callaway Plant License Renewal Application Amendment 25 The following change was made to add submerged (structural) as an environment for supports.

Section 3.5.2.1.12 (Pages 3.5-17 and 3.5-18) is revised as follows (new text underlined):

3.5.2.1.12 Supports Materials The materials of construction for the supports component types are:

Carbon Steel Concrete High Strength Low Alloy Steel (Bolting)

Lubrite Stainless Steel Environment The supports component types are exposed to the following environments:

Atmosphere/ Weather (Structural)

Borated Water Leakage Fuel Oil Plant Indoor Air (Structural)

Submerged (Structural)

ULNRC-06019 August 2, 2013 Page 13 of 31 Callaway Plant License Renewal Application Amendment 25 Changes made to add stainless steel mechanical equipment supports Class 2 and 3 in an external environment of submerged for the Essential Service Water pump supports. Also added carbon steel supports ASME 2 and 3 and mechanical equipment supports Class 2 and 3 in an external environment of fuel oil for the fuel oil storage tank fuel oil transfer pumps and associated piping.

Table 3.5.2-12 (Page 3.5-157, 3.5-160, 3.5-161 and 3.5-163) is revised as follows (new text underlined):

Table 3.5.2-12 Containments, Structures, and Component Supports - Summary of Aging Management Evaluation - Supports (Continued)

Component Type Intended Function Material Environment Aging Effect Requiring Management Aging Management Program NUREG-1801 Item Table 1 Item Notes Supports ASME 2 and 3 SS Carbon Steel Fuel Oil (External)

Loss of material ASME Section XI, Subsection IWF (B2.1.28)

None None G, 3 Supports Mech Equip Class 2 and 3 SS Carbon Steel Fuel Oil (External)

Loss of material ASME Section XI, Subsection IWF (B2.1.28)

None None G, 3 Supports Mech Equip Class 2 and 3 SS Stainless Steel Submerged (Structural)

(Ext)

Loss of material ASME Section XI, Subsection IWF (B2.1.28)

None None G

Notes for Table 3.5.2-12:

Standard Notes:

A Consistent with NUREG-1801 item for component, material, environment, and aging effect. AMP is consistent with NUREG-1801 AMP.

C Component is different, but consistent with NUREG-1801 item for material, environment, and aging effect. AMP is consistent with NUREG-1801 AMP.

ULNRC-06019 August 2, 2013 Page 14 of 31 E

Consistent with NUREG-1801 for material, environment, and aging effect, but a different aging management program is credited or NUREG-1801 identifies a plant-specific aging management program.

G Environment not in NUREG-1801 for this component and material.

Plant Specific Notes:

1 NUREG-1801 does not provide a line to evaluate stainless steel components outdoors under the ASME Section XI, Subsection IWF program (B2.1.29).

2 NUREG-1801 does not provide a line in Chapter III.B1.2 to evaluate a stainless steel component in an air-outdoor environment.

3.

IWF-1230 exempts supports from examination requirements that are connected to piping that is exempt from volumetric, surface, and VT-1 or VT-3 visual examination in accordance with IWD-1220. According to IWD-1220, Class 3 components and piping segments, 4-inch diameter and smaller, are exempt from VT-1 visual examination. See NUREG-1961 (PVNGS SER), Section 3.5.2.3.14.

ULNRC-06019 August 2, 2013 Page 15 of 31 Callaway Plant Unit 1 Page 4.3-35 License Renewal Application Amendment 25 Callaway Plant License Renewal Application Amendment 25 The pressurizer shell at support lug CUF value in the Plant Specific Limiting Locations Section of Table 4.3-6 was corrected from 0.922 to 0.992.

Table 4.3-6 pressurizer shell at support lug line (Page 4.3-35) was revised as follows (new text underlined and deleted text shown in strikethrough):

Table 4.3-6 Licensing Basis Uen for the Sentinel Locations Location Material CUF Fen Uen CUF-Fen Basis Further Eval.

Req.

Plant Specific Limiting Locations Pressurizer Shell at Support Lug Low Alloy Steel 0.92200.992 2.455 2.435 Design basis CUF NUREG/CR-6583 maximum Fen Yes

ULNRC-06019 August 2, 2013 Page 16 of 31 Callaway Plant Unit 1 Page 4.3-36 License Renewal Application Amendment 25 Callaway Plant License Renewal Application Amendment 25 The pressurizer shell at support lug Design CUF value in the Pressurizer Section of Table 4.3-7 was corrected from 0.922 to 0.992.

Table 4.3-7 pressurizer shell at support lug line (Page 4.3-36) was revised as follows (new text underlined and deleted text shown in strikethrough):

Table 4.3-7: Sentinel Locations for EAF Monitoring System Thermal Zone Material Component NUREG

/CR-6260 Design CUF Avg.

Fen Est. Uen Pressurizer PZR Lower Head SS

6. Pressurizer Heater Penetration N

0.562 13.117 7.372 PZR Spray SS

7. Pressurizer Spray Nozzle N

0.411 9.013 3.704 PZR SRV/PORV SS

8. Safety Valve Piping N

0.975 11.486 11.199 PZR Upper Head SS

9. Pressurizer Upper Instrument Nozzle N

0.236 13.117 3.096 LAS

10. Pressurizer Shell at Support Lug N

0.92200.992 2.455 2.435

ULNRC-06019 August 2, 2013 Page 17 of 31 Callaway Plant Unit 1 Page A-6 License Renewal Application Amendment 25 Appendix A Final Safety Analysis Report Supplement A1.10 OPEN-CYCLE COOLING WATER SYSTEM The Open-Cycle Cooling Water System program manages loss of material, wall thinning, reduction of heat transfer, cracking, blistering, change in color, and hardening and loss of strength for components within the scope of license renewal and exposed to the raw water of the essential service water system and heat exchangers and other components in other systems serviced by the essential service water system.

The program is consistent with commitments as established in responses to NRC Generic Letter 89-13, Service Water System Problems Affecting Safety-Related Components and includes:

(a) surveillance and control of biofouling, (b) tests to verify heat transfer, (c) routine inspection and maintenance program, (d) system walkdown inspection, and (e) review of maintenance, operating, and training practices and procedures.

The Open-Cycle Cooling Water System program includes the essential service water system that transfers heat from the safety-related structures, systems and components to the ultimate heat sink as defined in NRC Generic Letter 89-13. Periodic heat transfer testing or inspection and cleaning of heat exchangers with a heat transfer intended function is performed in accordance with commitments to NRC Generic Letter 89-13 to verify heat transfer capabilities.

ULNRC-06019 August 2, 2013 Page 18 of 31 Callaway Plant Unit 1 Page A-11 License Renewal Application Amendment 25 Appendix A Final Safety Analysis Report Supplement A1.20 ONE-TIME INSPECTION OF ASME CODE CLASS 1 SMALL-BORE PIPING The One-Time Inspection of ASME Code Class 1 Small-Bore Piping program manages cracking of ASME Code Class 1 piping less than four inches nominal pipe size (NPS 4) and greater than or equal to NPS 1.

For ASME Code Class 1 small-bore piping, the Risk-informed (RI-ISI) ISI program requires volumetric examinations (by ultrasonic testing) on selected butt weld locations to detect cracking. Weld locations are selected based on the guidelines provided in EPRI TR-112657, Revised Risk-Informed Inservice Inspection Evaluation Procedure. Ultrasonic examinations are conducted in accordance with ASME Section XI with acceptance criteria from paragraph IWB-3000 for butt welds.

The program will include a volumetric or opportunistic destructive examination of socket welds to identify potential cracking. Callaway has experienced one case of cracking, in 1995, of an ASME Code Class 1 small-bore piping butt weld resulting from cyclical loading which was mitigated with a design change to prevent recurrence. Eight small-bore Class 1 socket welds will be selected for examination, which represents 10 percent of the population. There are 77 80 Class 1 small-bore socket welds in the population of ASME Code Class 1 piping less than NPS 4 and greater than or equal to NPS 1 at Callaway. Alternatively, an opportunistic destructive examination may be used in lieu of volumetric examinations. An opportunistic destructive examination may be performed when a weld is removed from service for reasons other than inspection. Because more information can be obtained from a destructive examination than from a nondestructive examination, each weld destructively examined will be considered equivalent to having volumetrically examined two welds.

Socket welds that fall within the weld examination sample will be examined following ASME Section XI Code requirements. If a qualified volumetric examination procedure for socket welds endorsed by the industry or the NRC is available and incorporated into the ASME Section XI Code at the time of the small-bore inspections, then this will be used for the volumetric examinations. If no volumetric examination procedure for ASME Code Class 1 small-bore socket welds has been endorsed by the industry or the NRC and incorporated into ASME Section XI at the time Callaway performs inspections of small-bore piping, a plant procedure for volumetric examination of ASME Code Class 1 small-bore piping with socket welds will be used.

The program includes controls to implement an alternate plant-specific periodic inspection aging management program should evidence of ASME Class 1 small bore piping cracking caused by intergranular stress corrosion cracking or fatigue be confirmed by review of Callaway operating

ULNRC-06019 August 2, 2013 Page 19 of 31 Callaway Plant Unit 1 Page A-12 License Renewal Application Amendment 25 experience prior to the period of extended operation or by the examinations performed as part of this program.

The One-Time Inspection of ASME Code Class 1 Small-Bore Piping program is a new program and inspections will be completed and evaluated within six years prior to the period of extended operation.

In conformance with 10 CFR 50.55a(g)(4)(ii), the ISI program is updated during each successive 120-month inspection interval to comply with the requirements of the latest edition of the ASME Code specified twelve months before the start of the inspection interval. Callaway will use the ASME Code Edition consistent with the provisions of 10 CFR 50.55a during the 10-year period prior to the period of extended operation (fourth interval).

ULNRC-06019 August 2, 2013 Page 20 of 31 Callaway Plant Unit 1 Page A-21 License Renewal Application Amendment 25 Appendix A Final Safety Analysis Report Supplement A2

SUMMARY

DESCRIPTIONS OF TIME-LIMITED AGING ANALYSIS AGING MANAGEMENT PROGRAMS A2.1 FATIGUE MONITORING The Fatigue Monitoring program manages fatigue cracking caused by anticipated cyclic strains in metal components of the reactor coolant pressure boundary. The program ensures that actual plant experience remains bounded by the transients analyzed in the design calculations and fatigue crack growth analyses, or that corrective actions maintain the design and licensing basis. The Fatigue Monitoring program tracks the number of transient cycles and will track cumulative fatigue usage at monitored locations. The Fatigue Monitoring program tracks fatigue by one of the following methods:

1) The Cycle Counting (CC) monitoring method tracks transient event cycles affecting the location to ensure that the numbers of transient events analyzed by the fatigue analyses are not exceeded. This method does not calculate cumulative usage factors (CUFs).

2) The Cycle-Based Fatigue (CBF) monitoring method utilizes the CC results and stress intensity ranges generated with the ASME III methods that use three dimensional six component stress-tensor methods to perform CUF calculations for a given location. The fatigue accumulation is tracked to determine approach to the ASME allowable fatigue limit of 1.0.

3) The Stress-Based Fatigue (SBF) monitoring method computes a "real time" stress history for a given component from data collected from plant instruments to calculate transient pressure and temperature, and the corresponding stress history at the critical location in the component.

The stress history is analyzed to identify stress cycles, and then a CUF is computed. The CUF will be calculated using a three dimensional, six component stress tensor method meeting ASME III NB-3200 requirements, or a method will be benchmarked consistent with the NRC Regulatory Issue Summary RIS 2008-30.

The program will also consider the effects of the reactor water environment for a set that includes the NUREG/CR-6260 sample locations for a newer-vintage Westinghouse Plant, and plant-specific bounding EAF locations. If a cycle count or cumulative usage factor value increases to a program action limit, corrective actions include fatigue reanalysis, repair, or replacement. Action limits permit completion of corrective actions before the design limit is exceeded. The sentinel location analysis, when refined, will be revisited to confirm bounding Reactor Coolant Pressure Boundary Environmentally Assisted Fatigue susceptible sentinel locations are updated appropriately and remain bounded consistent with the refined analysis.

ULNRC-06019 August 2, 2013 Page 21 of 31 Callaway Plant Unit 1 Page B-31 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS B2.1.7 Flow-Accelerated Corrosion Program Description The Flow-Accelerated Corrosion (FAC) program manages aging effects of wall thinning on the internal surfaces of carbon or low alloy steel piping, elbows, reducers, expanders, and valve bodies which contain high energy fluids (both single phase and two phases). The program implements the EPRI guidelines in NSAC-202L-R3 to detect, measure, monitor, predict, and mitigate component wall thinning.

Analytical evaluations and periodic examinations of locations that are most susceptible to wall thinning due to FAC are used to predict the amount of wall thinning. Program activities include analyses to determine critical locations, baseline inspections to determine the extent of thinning at these critical locations, and follow-up inspections to confirm the predictions. Inspections are performed using ultrasonic, visual or other approved testing techniques capable of detecting wall thinning. Repairs and replacements are performed as necessary.

Where applicable, analyses to determine critical locations in piping and other components susceptible to FAC are performed utilizing CHECWORKSTM, a predictive code that uses the implementation guidance of NSAC-202L-R3. For each examined component, a verified and validated computer program, called FAC Manager Web Edition, is utilized in conjunction with CHECWORKSTM to calculate component wear, wear rate, and the next scheduled inspection. If a component's remaining life cannot be demonstrated to be more than one operating cycle, then corrective action is required, such as repair, replacement, or reevaluation.

No preventive attributes are directly associated with the FAC program. However, it is recognized that water chemistry monitoring to control pH and dissolved oxygen content, as well as the chromium content of the piping material, are effective in reducing FAC. The program considers water treatment changes that may affect the FAC rates.

The Open-Cycle Cooling Water System program (B2.1.10) manages wall thinning due to erosion in the essential service water (ESW) system. Outside the ESW system, Callaway has not experienced wall thinning due to erosion in components within the scope of License Renewal.

NUREG-1801 Consistency The Flow-Accelerated Corrosion program is an existing program that is consistent with NUREG-1801,Section XI.M17, Flow-Accelerated Corrosion.

ULNRC-06019 August 2, 2013 Page 22 of 31 Callaway Plant Unit 1 Page B-32 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS Exceptions to NUREG-1801 None Enhancements None Operating Experience The following discussion of operating experience provides objective evidence that the FAC program will be effective in ensuring that intended functions are maintained consistent with the current licensing basis for the period of extended operation:

1. A review of a 10 year period of corrective action reports showed that there has been one FAC-related leak or rupture at Callaway during that time.

In August 1999, the six-inch normal drain line from the first stage moisture separator reheater drain tank to the 6B high pressure feedwater heater ruptured. The severe FAC damage was caused by unusual two-phase flow conditions set up by a combination of a long horizontal line followed by two elbows in close proximity combined with inside pipe discontinuities such as weld backing rings. The wear rate predicted by the then-current version of CHECWORKSTM was only 0.003 in./year, so that it wasn't scheduled to be inspected until Refuel 10, which started six weeks following the failure.

As corrective action for the above event, over 40 locations with similar geometry and fluid conditions were inspected immediately. No similar problems were identified by these inspections. The carbon steel piping and fittings in this line were replaced with FAC-resistant materials. This pipe was added to Callaways FAC program.

2. A review of refueling outage FAC inspection reports since 2001 showed that wall thinning was identified during the FAC program inspections. There were cases where the allowable thickness determined in accordance with the program guidelines was reached and more rigorous stress analyses were performed to justify continued service and to postpone the replacement. In other cases, the component was repaired or replaced. In Refuel 11 (Spring 2001), unexpected wall thinning was found in feedwater piping, requiring expansion of the scope of the inspections and extensive replacement of the piping. The locations had not been modeled in CHECWORKSTM due to personnel error. In Refuel 13 (Spring 2004), the scope of inspections was expanded due to inspection results.

Replacements for each outage are scheduled proactively, determined by the projected remaining service life based on FAC analyses, by programmatic strategy, and cost comparison to further inspections. Most replacements are of FAC-resistant materials such as stainless steel and chrome-moly alloy.

ULNRC-06019 August 2, 2013 Page 23 of 31 Callaway Plant Unit 1 Page B-33 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS The operating experience of the Flow-Accelerated Corrosion program shows that the program effectively monitors and trends the aging effects of FAC on piping and components and takes appropriate corrective action prior to loss of intended function. Occurrences that would be identified under the Flow-Accelerated Corrosion program will be evaluated to ensure there is no significant impact to safe operation of the plant and corrective actions will be taken to prevent recurrence. Guidance for re-evaluation, repair, or replacement is provided for locations where aging is found. There is confidence that the continued implementation of the Flow-Accelerated Corrosion program will effectively identify aging prior to loss of intended function.

Conclusion The continued implementation of the Flow-Accelerated Corrosion program provides reasonable assurance that aging effects will be managed such that the systems and components within the scope of this program will continue to perform their intended functions consistent with the current licensing basis for the period of extended operation.

ULNRC-06019 August 2, 2013 Page 24 of 31 Callaway Plant Unit 1 Page B-41 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS B2.1.10 Open-Cycle Cooling Water System Program Description The Open-Cycle Cooling Water (OCCW) System program manages loss of material, wall thinning, reduction of heat transfer, cracking, blistering, change in color, and hardening and loss of strength for those components that are exposed to the raw water environment of the essential service water (ESW) system and heat exchangers and other components in other systems serviced by the essential service water system.

The activities for this program are consistent with the Callaway commitments to the requirements of NRC Generic Letter 89-13, Service Water System Problems Affecting Safety-Related Components and provide for management of aging effects in raw water cooling systems through tests, inspections and component cleaning. System and component testing, visual inspections, nondestructive examination (i.e., ultrasonic testing and eddy current testing), and biocide and chemical treatment are conducted to ensure that aging effects are managed such that system and component intended functions and integrity are maintained.

Periodic heat transfer testing or inspection and cleaning of heat exchangers with a heat transfer intended function is performed in accordance with Callaway commitments to NRC Generic Letter 89-13 to verify heat transfer capabilities.

Routine inspections and maintenance of the OCCW System program ensure that corrosion, erosion, sediment deposition and biofouling cannot degrade the performance of safety-related systems serviced by the essential service water system.

The guidelines of NRC Generic Letter 89-13 are utilized for the surveillance and control of biofouling. Procedures provide instructions and controls for biocide injection. Periodic inspections are performed for the presence of mollusks and biocide treatments are applied as necessary.

System walkdowns are performed periodically to assess the material condition of OCCW system piping and components. Compliance with the licensing basis is ensured by review of system design basis documents as well as periodic performance of self assessments.

Callaway uses internal coatings only on the component cooling water heat exchanger end bells, channels, and tubesheets; the control room air conditioner tubesheets; the class 1E electrical equipment air conditioner tubesheets; and the essential service water system strainers. This amount of coating surface area is relatively small and its aging has not been a concern for essential service water system performance.

ULNRC-06019 August 2, 2013 Page 25 of 31 Callaway Plant Unit 1 Page B-42 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS Examination of polymeric materials by OCCW System program will be consistent with examinations described in the Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components program (B2.1.23).

The external surfaces of the buried OCCW components are managed by the Buried and Underground Piping and Tanks program (B2.1.25). The aging management of closed-cycle cooling water systems is described in B2.1.11, Closed Treated Water Systems program, and is not included as part of this program.

NUREG-1801 Consistency The Open-Cycle Cooling Water System program is an existing program that, following enhancement, will be consistent with NUREG-1801,Section XI.M20, Open-Cycle Cooling Water System.

Exceptions to NUREG-1801 None Enhancements Prior to the period of extended operation, the following enhancements will be implemented in the following program elements:

Parameters Monitored or Inspected (Element 3), Detection of Aging Effects (Element 4), and Acceptance Criteria (Element 6)

Procedures will be enhanced to include polymeric material inspection requirements, parameters monitored, and acceptance criteria. Examination of polymeric materials by OCCW System program will be consistent with examinations described in the Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components program (B2.1.23).

Procedures will be enhanced to include inspection and cleaning, if necessary, of the air-side of safety-related air-to-water heat exchangers cooled by essential service water.

Preventive Actions (Element 2), Parameters Monitored or Inspected (Element 3), Detection of Aging Effects (Element 4), and Acceptance Criteria (Element 6)

Procedures will be enhanced to inspect the essential service water strainers for coating degradation.

ULNRC-06019 August 2, 2013 Page 26 of 31 Callaway Plant Unit 1 Page B-43 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS Preventive Actions (Element 2), Parameters Monitored or Inspected (Element 3), Detection of Aging Effects (Element 4), Monitoring and Trending (Element 5) and Acceptance Criteria (Element 6)

Procedures will be enhanced to inspect for coating detachment indications that could affect downstream components during internal coatings inspections and specify acceptance criteria for coating detachment indications. Coatings detachments that are not repaired or removed to leave sound coating bonded to the surface will be evaluated to confirm coating manufacturer installation requirements, tested using techniques identified in ASTM-D7167 to confirm if the coating is bonded to the surface, and trended.

Operating Experience The following discussion of operating experience provides objective evidence that the Open-Cycle Cooling Water System program will be effective in ensuring that intended functions are maintained consistent with the current licensing basis for the period of extended operation:

1. In 2000, during routine maintenance, Asiatic clams were found in an RHR room cooler, blocking approximately 15 percent of the tubes. In subsequent inspections, clams were found in several service water and essential service water heat exchangers and room coolers. It was determined that the clams originated in the waste treatment clearwell, from which they were flushed into the suction of the service water pumps. The service water pumps distributed the clams to the heat exchangers and room coolers. As corrective action, procedures were strengthened to require more frequent inspections and provide for a more robust chemistry program to control the clams. Corrective action also included plant modifications, such as installing strainers on the discharge line of the service water pumps.

2. In 2001, through-wall corrosion had been observed in the RHR pump room cooler. The exact cause could not be determined but was believed to be from microbiologically influenced corrosion attack. The cooler was repaired.

3. Performance of the containment coolers degraded over time due to debris from the service water system, so that by 2001 there was very little margin available. The design of the original containment cooler coils did not allow them to be mechanically cleaned, and flushing was ineffective. The coils for containment coolers A and B were replaced in Refuel 11 (Spring 2001), and the coils for C and D were replaced in Refuel 12 (Fall 2002). The replacement coils have a removable cover plate which permits access to mechanically clean individual tubes.

ULNRC-06019 August 2, 2013 Page 27 of 31 Callaway Plant Unit 1 Page B-44 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS

4. In 2007, Callaway revised the program so that the component cooling water heat exchangers are the only heat exchangers that are performance tested. In order to maintain heat removal capability of the other NRC Generic Letter 89-13 heat exchangers, Callaway cleans and inspects heat exchangers at regular intervals, as well as performs flow and pressure measurements according to the essential service water flow balance procedure. The inspections check for micro-fouling, and include thermographies or ultrasonic examinations of internal surfaces. These maintenance activities supplement the commitment to thermal performance testing made in response to NRC Generic Letter 89-13. The primary and additional monitoring methods have been determined for each of the NRC Generic Letter 89-13 heat exchangers, in accordance with the guidance of EPRI Technical Report 1007248, Alternative to Thermal Performance Testing and/or Tube-side Inspections of Air-to-Water Heat Exchangers.

5. In 2007 while performing UT inspections, it was discovered that the top portion of the 'B' ESW pump discharge piping was partially eroded. Extent of condition inspections identified a similar condition on the discharge of the 'A' ESW pump. The piping segments were replaced and added to the Raw Water monitoring program to inspect the segments for erosion.

56. From 2008 to 2009, the buried portions of the ESW supply from the ESW pump house and return to the ultimate heat sink cooling tower were replaced with high-density polyethylene (HDPE) piping. In addition, sections of above ground or underground carbon steel piping that interfaces with the buried piping was replaced with stainless steel piping. These modifications were performed as a result of the material condition of the ESW system. These modifications were performed as a result of corrective action documents that have been written concerning pinhole leaks, pitting, and other localized degradation of the ESW piping system.

67. In 2009, the replacement of the emergency diesel generator jacket water heat exchangers was evaluated due to loss of material in the tubes. The evaluation determined that a better material of construction and a better design would minimize aging effects due to raw water environment in the emergency diesel generators. The replacement jacket water heat exchangers and the emergency diesel generator lube oil coolers had tubes made of AL6XN stainless steel and were replaced in Refuel 17 (Spring 2010). The emergency diesel generator intercoolers were replaced in Refuel 18 (Fall 2011), and also have tubes fabricated from AL6XN stainless steel.

78. In 2009, room cooler flow rates had been observed to be low in the RHR pump room cooler and the containment spray pump room cooler. The low flow rates were

ULNRC-06019 August 2, 2013 Page 28 of 31 Callaway Plant Unit 1 Page B-45 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS determined to be from material that was dislodged during weld repairs from the outage prior to flow testing. The coolers were flushed to remove the debris, and flow rates were restored to their normal operating condition.

89. Prior to 2010, the coils for the following safety-related room coolers were replaced due to performance or aging issues: auxiliary building north penetration room cooler, auxiliary building south penetration room cooler, component cooling water pump room cooler train A, component cooling water pump room cooler train B, and spent fuel pool room cooler A. The material for the replacement coils is AL6XN stainless steel.

The above examples provide objective evidence that the existing Open-Cycle Cooling Water System program preventive, condition, and performance monitoring activities prevent or detect aging effects. Occurrences that would be identified under the Open-Cycle Cooling Water System program will be evaluated to ensure there is no significant impact to safe operation of the plant and corrective actions will be taken to prevent recurrence. Guidance for re-evaluation, repair, or replacement is provided for locations where aging is found.

There is confidence that the continued implementation of the Open-Cycle Cooling Water System program will effectively identify aging prior to loss of intended function.

Conclusion The continued implementation of the Open-Cycle Cooling Water System program, following enhancement, will provide reasonable assurance that aging effects will be managed such that the systems and components within the scope of this program will continue to perform their intended functions consistent with the current licensing basis for the period of extended operation.

ULNRC-06019 August 2, 2013 Page 29 of 31 Callaway Plant Unit 1 Page B-72 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS B2.1.20 One-Time Inspection of ASME Code Class1 Small-Bore Piping Program Description The One-Time Inspection of ASME Code Class 1 Small-Bore Piping program manages cracking of ASME Code Class 1 piping less than four inches nominal pipe size (NPS) and greater than or equal to NPS 1.

For ASME Code Class 1 small-bore piping, the Risk-informed (RI-ISI) ISI program requires volumetric examinations (by ultrasonic testing) on selected butt weld locations to detect cracking. Weld locations are selected based on the guidelines provided in EPRI TR-112657, Revised Risk-Informed Inservice Inspection Evaluation Procedure. There are 340 343 Class 1 small-bore butt welds less than NPS 4 and greater than or equal to NPS 1 at Callaway. At least 25 butt welds will be included in the examination population. Ultrasonic examinations are conducted in accordance with ASME Section XI with acceptance criteria from paragraph IWB-3000 for butt welds.

The program will include a volumetric or opportunistic destructive examination of socket welds to identify potential cracking. Callaway has experienced one case of cracking, in 1995, of an ASME Code Class 1 small-bore piping butt weld resulting from cyclical loading which was mitigated with a design change to prevent recurrence. Eight small-bore Class 1 socket welds will be selected for examination, which represents 10 percent of the population. There are 77 80 Class 1 small-bore socket welds in the population of ASME Code Class 1 piping less than NPS 4 and greater than or equal to NPS 1 at Callaway.

Alternatively, an opportunistic destructive examinations examination may be used in lieu of a volumetric examination. An opportunistic destructive examination may be performed when a weld is removed from service for reasons other than inspection. Because more information can be obtained from a destructive examination than from a nondestructive examination, each weld destructively examined will be considered equivalent to having volumetrically examined two welds. When selecting socket welds for examination, consideration will be given to selecting welds which are susceptible to cracking resulting from stress corrosion, cyclical (including thermal, mechanical, and vibration fatigue) loading, or thermal stratification and thermal turbulence. At least one socket weld selected for examination will have a risk ranking of "high", as determined by the RI-ISI program.

Socket welds that fall within the weld examination sample will be examined following ASME Section XI Code requirements. If a qualified volumetric examination procedure for socket welds endorsed by the industry or the NRC is available and incorporated into the ASME Section XI Code at the time of the small-bore inspections, then this will be used for the

ULNRC-06019 August 2, 2013 Page 30 of 31 Callaway Plant Unit 1 Page B-73 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS volumetric examinations. If no volumetric examination procedure for ASME Code Class 1 small-bore socket welds has been endorsed by the industry or the NRC and incorporated into ASME Section XI at the time Callaway performs inspections of small-bore piping, a plant procedure for volumetric examination of ASME Code Class 1 small-bore piping with socket welds will be used.

The program includes controls to implement an alternate plant-specific periodic inspection aging management program should evidence of ASME Class 1 small bore piping cracking caused by intergranular stress corrosion cracking or fatigue be confirmed by review of Callaway operating experience prior to the period of extended operation or by the examinations performed as part of this program.

The One-Time Inspection of ASME Code Class 1 Small-Bore Piping program inspections will be completed and evaluated within the six-year period prior to the period of extended operation.

In conformance with 10 CFR 50.55a(g)(4)(ii), the ISI program is updated during each successive 120-month inspection interval to comply with the requirements of the latest edition of the ASME Code specified twelve months before the start of the inspection interval.

Callaway will use the ASME Code Edition consistent with the provisions of 10 CFR 50.55a during the 10 year period prior to the period of extended operation (fourth interval).

NUREG-1801 Consistency The One-Time Inspection of ASME Code Class 1 Small-Bore Piping program is a new program that, when implemented, will be consistent with NUREG-1801,Section XI.M35, One-Time Inspection of ASME Code Class 1 Small-Bore Piping.

Exceptions to NUREG-1801 None Enhancements None Operating Experience The following discussion of operating experience provides objective evidence that the One-Time Inspection of ASME Code Class 1 Small-Bore Piping program will be effective in

ULNRC-06019 August 2, 2013 Page 31 of 31 Callaway Plant Unit 1 Page B-74 License Renewal Application Amendment 25 Appendix B AGING MANAGEMENT PROGRAMS ensuring that intended functions are maintained consistent with the current licensing basis for the period of extended operation:

1 A review of plant-specific operating experience indicates that one event of cracking has been observed for an ASME Code Class 1 small-bore pipe butt weld less than NPS 4.

In 1995, an ASME Class 1 butt weld on a two inch RCS Loop D crossover leg to chemical and volume control system excess letdown line developed a crack. The most probable cause was the combined effects of 1) high stresses resulting from interference with a flange/plate and 2) normal system vibration. The flange/plate was removed to prevent recurrence of this weld failure. A volumetric examination (UT) of the weld performed during Refuel 17 (Spring 2010) using the techniques described in MRP-146 identified no indications. There have been no additional failures since 1995.

Occurrences that would be identified under the One-Time Inspection of ASME Code Class 1 Small-Bore Piping program will be evaluated to ensure there is no significant impact to safe operation of the plant and corrective actions will be taken to prevent recurrence. Guidance for re-evaluation, repair, or replacement is provided for locations where aging is found.

There is confidence that the implementation of the One-Time Inspection of ASME Code Class 1 Small-Bore Piping program will effectively identify aging prior to loss of intended function.

Industry and plant specific operating experience will be evaluated in the development and implementation of this program.

Conclusion The implementation of the One-Time Inspection of ASME Code Class 1 Small-Bore Piping program will provide reasonable assurance that aging effects will be managed such that the systems and components within the scope of this program will continue to perform their intended functions consistent with the current licensing basis for the period of extended operation.