GO2-11-029, Response to Request for Additional Information License Renewal Application

Response to Request for Additional Information License Renewal Application

ML110320419
Person / Time
Site:	Columbia
Issue date:	01/28/2011
From:	Gambhir S Energy Northwest
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
GO2-11-029
Download: ML110320419 (18)

Text

EN ERGY EGSudesh K. Gambhir Vice President, Engineering

-I4Richland,

//EI P.O. Box 968, WA Mail 99352-0968 Drop PE04 NORTH W EST Ph. 509-377-8313 F. 509-377-2354 sgambhia@energy-northwest.com January 28, 2011 G02-11-029 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001

Subject:

COLUMBIA GENERATING STATION, DOCKET NO. 50-397 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION

References:

1) Letter, G02-1 0-11, dated January 19, 2010, WS Oxenford (Energy Northwest) to NRC, "License Renewal Application"

2) Letter dated December 27, 2010, NRC to SK Gambhir (Energy Northwest), "Request for Additional Information for the Review of the Columbia Generating Station, License Renewal Application," (ADAMS Accession No. MLI103550603)

Dear Sir or Madam:

By Reference 1, Energy Northwest requested the renewal of the Columbia Generating Station (Columbia) operating license. Via Reference 2, the Nuclear Regulatory Commission (NRC) requested additional information related to the Energy Northwest submittal.

Transmitted herewith in the Attachment is the Energy Northwest response to the Request for Additional Information (RAI) contained in Reference 2. Enclosure 1 contains Amendment 26 to the Columbia License Renewal Application. One new commitment and one revised commitment are included in this response.

If you have any questions or require additional information, please contact Abbas Mostala at (509) 377-4197.

Aa-

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 2 of 2 I declare under penalty of perjury that the foregoing is true and correct. Executed on the date of this letter.

Respectfully, KGambhir Vice President, Engineering

Attachment:

Response to Request for Additional Information

Enclosure:

License Renewal Application Amendment 26 cc: NRC Region IV Administrator NRC NRR Project Manager NRC Senior Resident Inspector/988C EFSEC Manager RN Sherman - BPA/1 399 WA Horin - Winston & Strawn AD Cunanan - NRC NRR (w/a)

BE Holian - NRC NRR RR Cowley - WDOH

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 1 of 9 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION "Request for Additional Information for the Review of the Columbia Generating Station, License Renewal Application,"

(ADAMS Accession No. ML103550603)

Gavula RAIs B.2.26-6 and B.2.42-4

Background:

Pursuant to 10 CFR 54.21 (a)(3), a license renewal applicant is required to demonstrate that the effects of aging on structures and components subject to an aging management review (AMR) will be adequately managed so that their intended functions will be maintained consistent with the current licensing basis for the period of extended operation.

In its review of the Fire Water System and Open-Cycle Cooling Water System Programs, the staff identified that the applicant has plant-specific operating experience for loss of material due to cavitation erosion in both its fire protection and standby service water systems. As a result, the staff issued requests for additional information (RAIs) B.2.26-5 and B.2.42-3 regarding the extent of condition review performed to identify the potential for cavitation erosion in other systems at the station and the actions taken to manage the aging effects of cavitation erosion at susceptible locations.

In its response, dated September 27, 2010, Energy Northwest stated that the root cause analysis performed in 2002 had incorrectly concluded that high energy systems were addressed by the flow-accelerated corrosion (FAC) program, although it was later determined that the existing FAC program does not check for cavitation erosion. The response also stated that a piping system cavitation guide had been developed using several industry documents; however, the criteria for predicting locations with the potential for cavitation erosion were not provided. The response further stated that Energy Northwest did not intend to provide justification of the incomplete 2002 extent of condition review, as this is a current license issue which had been entered into the corrective action program and would include an extent of condition review. The response also stated that repetitive preventative maintenance tasks were established to ensure that ultrasonic inspections occur at the locations susceptible to cavitation erosion in the fire protection piping.

License renewal application (LRA) Section B.2.26 and Commitment No.26 state an enhancement to the Fire Protection Program to " ... perform either

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 2 of 9 ultrasonic testing or internal visual inspection of representative portions of the above-ground fire protection piping, which normally do not experience flow." The LRA does not include any information regarding what specific examinations will be performed to manage cavitation erosion.

Issue:

Given that the extent of condition review for cavitation erosion at the station was incomplete, the staff cannot evaluate whether all of the aging effects requiring management have been identified for the components in those systems susceptible to cavitation erosion, or whether the existing aging management programs are adequate to manage loss of material due to cavitation erosion for all susceptible components.

In addition, since the criteria for predicting locations with a potential for cavitation erosion were not provided, a comparison with the mechanism-specific criteria in NRC-approved Electric Power Research Institute (EPRI) TR-1 12657, "Revised Risk-Informed Inservice Inspection Evaluation Procedure," could not be made.

Given that the Fire Protection Program enhancement allows either ultrasonic testing or visual inspections to detect loss of material, it is unclear to the staff how the ultrasonic inspections at the locations susceptible to cavitation erosion in the fire protection piping are included within the scope of the Fire Protection Program.

Request:

1) Provide the complete list of AMR line items that are susceptible to loss of material due to cavitation erosion and describe any proposed changes to the existing aging management programs required to manage loss of material due to cavitation erosion for these components.

2) Describe the criteria used in the extent of condition evaluation for cavitation erosion, and, if it is different, also describe the criteria in the above referenced piping system cavitation guide. If either set of criteria are less conservative than the mechanism-specific criteria in NRC-approved EPRI TR-1 12657, "Revised Risk-Informed Inservice Inspection Evaluation Procedure," provide the technical bases to demonstrate that the criteria used will provide reasonable assurance that component intended functions will be maintained during the period of extended operation.

3) Clarify how the repetitive preventative maintenance tasks which perform ultrasonic inspections at the locations susceptible to cavitation erosion in the fire protection piping are included within the scope of the Fire Protection Program.

Energy Northwest Response:

1) The complete list of AMR line items that are known to be susceptible to loss of material due to cavitation erosion is at the end of this response. The systems that are

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 3 of 9 considered susceptible to cavitation are standby service water (SW), plant service water (TSW), circulating water (CW), tower makeup (TMU), and fire protection (FP). Two systems, condensate (COND) and reactor feedwater (RFW), were not included in the original scope of the resolution of PER 202-1977. CR 223391 was written to screen COND and RFW for cavitation. A commitment is being added to Table A-1 to ensure that the COND and RFW systems are screened and evaluated for cavitation prior to entering the period of extended operation (PEO); if the in-scope portion of either system is determined to be susceptible to loss of material due to cavitation erosion, then a program(s) will be modified or created to manage the loss of material. The commitment and revised Table A-1 are included in Amendment 26.

The Open Cycle Cooling Water Program in LRA section B.2.42 already includes a required enhancement to address loss of material due to cavitation erosion and does not need modification. Changes are needed to adequately manage cavitation erosion of the FP system and the changes are discussed in the response to part 3 of this RAI for the Fire Water Program.

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 4 of 9 Table 3.3.2-1 Aging Management Review Results - Circulating Water System Row Component Intended Material Environment Aging Effect Aging Management NUREG- Table 1 Notes No. Type Function(s) Requiring Program 1801 Item Management Volume 2 Item 5 Piping Pressure Steel Raw water Loss of material Open-Cycle Cooling VII.C1-19 3.3.1-76 B boundary (Internal) Water 10 Valve Body Pressure Gray Cast Raw water Loss of material Open-Cycle Cooling VI1.C1-19 3.3.1-76 B boundary Iron (Internal) Water 13 Valve Body Pressure Steel Raw water Loss of material Open-Cycle Cooling VII.C1-19 3.3.1-76 B boundary (Internal) Water Table 3.3.2-22 Aging Management Review Results -Fire Protection System Row Component Intended Material Environment Aging Effect Aging NUREG- Table Notes No. Type Function(s) Requiring Management 1801 1 Item Management Program Volume 2 Item 91 Piping Structural Steel Raw water Loss of Fire Water VII.G-24 3.3.168 A integrity (Internal) material 168 Valve Body Pressure Gray Cast Raw water Loss of Fire Water VII.G-24 3.3.168 A boundary Iron (Internal) material Table 3.3.2-28 Aging Management Review Results - Plant Service Water System Row Component Intended Aging Effect 'Aging NUREG-Now Type Function(s) Material Environment Requiring Management Volume 1 Item Notes Management Program 2 Item 19 Piping Structural Steel Raw water Loss of material Open-Cycle VII.C1-19 3.3.176 B integrity (Internal) LossofmateriaCooling Water 35 Valve Body Structural Steel Raw water Loss Open-Cycle VII.C1-19 3.3.176 B I I integrity Steel _(Internal) mr Cooling Water Iof 3.3.17

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 5 of 9 Table 3.3.2-42 Aging Management Review Results - Standby Service Water System Row Component Intended Material Environment Aging Effect Aging NUREG- Table 1 Notes No. Type Function(s) Requiring Management 1801 Item Management Program Volume 2 Item 48 Piping Pressure Stainless Raw water Loss of Open-Cycle VII.C1-15 3.3.179 B boundary Steel (Internal) material Cooling Water 54 Piping Pressure Steel Raw water Loss of Open-Cycle VII.C1-19 3.3.176 B boundary (Internal) material Cooling Water 101 Valve Body Pressure Steel Raw water Loss of Open-Cycle VII.C1-19 3.3.176 B boundary (Internal) material Cooling Water Table 3.3.2-43 Aging Management Review Results - Tower Makeup Water System Row Component Intended Material Environment Aging Effect Aging NUREG- Table 1 Notes No. Type Function(s) Requiring Management 1801 Item Management Program Volume 2 Item 13 Piping Pressure Steel Raw water Loss of Open-Cycle VII.C1-19 3.3.176 B boundary (Internal) material Cooling Water 37 Valve Body Pressure Steel Raw water Loss of Open-Cycle VII.C1-19 3.3.176 B boundary (Internal) material Cooling Water

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 6 of 9

2) The criteria used for the extent of condition evaluation for cavitation and erosion for PER 202-1977 were contained in Energy Northwest document "Piping System Cavitation Evaluation Guide". Those criteria have since been captured in Energy Northwest Engineering Standards Manual MES-7, "Pipe Sizing Guide" as Appendix A.

The Piping System Cavitation Guide addressed the potential for cavitation in water system piping components, including valves (control and standard), orifices, and piping elbows. The Guide was developed to address a corrective action Problem Evaluation Request (PER) 202-1977, Pinhole Leak on Weld on the Downstream Side of SW-V-12B. It was intended to be a generic guide to aid system engineers in identifying/predicting locations in their water system piping with potential for sustaining cavitation damage. Once potential locations of cavitation are identified, vibration or acoustic measurements and piping wall thickness measurements can be taken to confirm the presence of cavitation and/or cavitation damage.

The guide gave an overview on the types and severity levels of cavitation. In order to help system engineers narrow down potential sources of cavitation in water systems, a list of indications that there is potentially a problem with cavitation in a component or components of a water piping system and a checklist were included. Indications included noise in a system or component, elbows with water flow in excess of 24 ft/s, valves used for throttling operations that are not designed for throttling, such as gate, ball, and butterfly valves, and valves that are closed or opened against full system pressure and flow, especially high recovery valves, such as gate, ball, cone, angle, and butterfly valves. One can assume that cavitation will occur at some point during the closing or opening operation.

Guidelines and a table of inlet pressure range versus minimum pressure drop for incipient cavitation potential was provided for orifices.

Once components with potential for cavitation are identified, the incipient cavitation number (ICN) for the components can be calculated to help better identify which components are candidates for taking measurements (vibration, thickness, etc.) to confirm presence of cavitation. The ICN was explained that since incipient cavitation does not cause damage unless only a small part of the flow is involved, use of the ICN should give conservative results.

A formula was provided to calculate the ICN for valves and orifices with a threshold ICN for high recovery valves, such as gate, ball, cone, angle, and butterfly of 15 or less, and for low recovery valves, such as globe valves, an ICN of 8 or less [ref. 3]. For orifices, an ICN of 8 or less would indicate potential for incipient cavitation [ref. 4]. Note that if the valve is a control valve that is designed for the pressure drop that it is subjected to, an ICN of 8 or less may not be indicative of potential cavitation problems.

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 7 of 9 ICN 1 (a,) = [Pinlet- (Pvap- Patn)] (formula from Ref. 3)

(Pinlet - Poutlet)

Where:

Piniet = Gage Pressure at Inlet of Valve or Orifice (psig)

Poutlet = Gage Pressure at Outlet of Valve or Orifice (psig)

Pvap = Absolute Vapor Pressure of Fluid at Fluid Temperature (psia)

Patm = Atmospheric Pressure (psi)

The formula below can be used to calculate the ICN number for elbows. For elbows, an ICN of 6 or less would indicate potential for incipient cavitation [ref. 6].

ICN 2 (a 2) = 2[(Piet+ (o12)(V )) - (Pvap - Patm)] (formula from Ref. 1) 2 (p)(V)

Where:

Piniet = Gage Pressure at Inlet of Elbow (psfg) - Note: If pressure at inlet of elbow is unknown, can use 0 psfg for a very conservative result.

Pvap Absolute Vapor Pressure of Fluid at Fluid Temperature (psfa)

Patm = Atmospheric Pressure (psf) p = Mass Density of Fluid at Fluid Temperature (slugs/ft3)

V = Fluid Velocity in Pipe (ft/s)

References:

(Note- As used in guide, but not all are used in above discussion)

1. EPRI report for predicting cavitation in power plants.

2. Chemical Engineers' Handbook, Fifth Edition

3. ISA-RP75.23-1995, Considerationsfor Evaluating Control Valve Cavitation, Approved 6/2/1995.

4. NUREG/CR-6031, Cavitation Guide for Control Valves, Table 6.4

5. WNP-2 Specifications, Mechanical EngineeringCriteria,Div. 1, Section 1E, p. 1E-54

6. ME-02-96-28, Evaluation of Cavitation Potentialin the SW System, Washington Public Power Supply System Mechanical Engineering Calculation The criteria used in the extent of condition evaluation for cavitation erosion (now captured in MES-7) and EPRI TR-1 12657 Rev. B-A is different for valves. Both methods use the same equation for elbows. EPRI TR-1 12657 Rev. B-A uses a different formula for valves, different initial screening criteria, and different threshold values. The EPRI formula uses Pdownstream while the MES-7 method uses Pinlet.

MES-7 uses a values of LT 15 or 8 for cavitation analysis, based on high recovery and low recovery valves, respectively. These a values come from ISA-RP75.23-1995. It has been observed that these a values are higher than found on page 93 of EPRI TR-103198-T1, which states that a should be LT 5 with a velocity of GT 30 ft/s. The MES-7

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 8 of 9 a values should be higher, as the MES-7 values for a are for incipient cavitation, while the EPRI TR-103198-Tl a value is for "cavitation erosion". Incipient cavitation does not cause erosion; it causes intermittent noise.

The levels of cavitation, from less to more severe, are incipient, critical (constant),

incipient damage and choking. Incipient and critical forms of cavitation are considered acceptable in piping design, as these forms cause little or no damage. These levels have cavitation values of descending value, meaning the lower the value the greater the damage potential. For example, EPRI TR-103198-T1, Figure 35 on page 74, gives cavitation numbers of approximately 7, 5.3, 2.9 and 1.7 for 90 degree bends in 6 inch pipe for incipient, critical (constant), incipient damage and choking, respectively.

Therefore, if the bend has a calculated a value of 6, it may be experiencing incipient cavitation but not critical, damage or choking cavitation.

It should also be noted that EPRI TR-103198-T1 describes the following correlation as a "rather coarse criteria" for identification of potential cavitation erosion:

Pd Pv < 5 Equation 1 A

and V > 10 m/s.

The V > 10 m/s is significant in that a review of NUREG/CR-6031 examples reveals that in all the cases described, damaging forms of cavitation did not occur until velocities exceeded 30 ft/s. A review of Columbia Generating Station (Columbia) piping velocities indicates that most flow rates are less than 15 ft/s (feedwater was the exception at 27 ft/s) with none exceeding 30 ft/s. Therefore, this equation would not apply to Columbia.

Cavitation erosion occurs after incipient cavitation occurs. Therefore, it is not inconsistent for MES-7 to use a higher acceptance criterion, since MES-7 uses the more conservative incipient cavitation as a design point. In other words, the MES-7 acceptance criteria was based on minimizing incipient cavitation, the lowest and a non-damaging form of cavitation, while the EPRI TP-103198 acceptance criteria allows incipient and critical cavitation, but not damaging cavitation. Therefore, MES-7 provides more margin to actual damaging cavitation than the EPRI document.

It has been observed that the equation above uses downstream pressure while the equation in MES-7 uses upstream pressure. The use of upstream pressure results in a higher calculated cavitation value in a scale where lower values are more damaging.

This would be non-conservative, if the acceptance values in MES-7 were based on the EPRI document. However, the acceptance values are based on ISA RP75.23-1995.

Per NUREG/CR-6031, page 13, it is acceptable to use upstream pressure. It is also acceptable to use downstream pressure. Per NUREG/CR-6031, page 14 equation 2.3 the two methods are related by:

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 9 of 9 au ad + 1 Where subscript 'u' equates to upstream pressure and 'd' to downstream pressure.

Therefore, Equation 1 above is equivalent to:

Pu - Pv

• .- <6 6 Ap MES-7 uses an acceptance value of 8 or 15, both of which are more conservative than 6, since they place a more restrictive limit on the pressure drop across the component (allow less pressure drop).

In conclusion, the use of upstream pressure is an acceptable practice per NUREG/CR-6031, and the acceptance values of MES-7 are conservative in respect to EPRI TR-103198-T1, equation 100.

3) Energy Northwest will enhance the Fire Water Program (FWP) to credit ultrasonic examination in cavitation susceptible locations. The associated LRA amendment 26 pages are included as enclosure 1. The commitment associated with the Table A-i, Item 26 change is included as enclosure 1.

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE RENEWAL APPLICATION Page 1 of 1 License Renewal Application Amendment 26 Section No. Page No. RAI Response Table A-1 RAIs B.2.26-6 and Line Item 26 A-51 B.2.42-4 Table A-i -5 RAls B.2.26-6 and Line Item 26 B.2.42-4 Table A-1 RAIs B.2.26 and Line Item 67 A-68c B.2.42-4 Table A-1 RAIs B.2.26 and Line Item 67 A-68d B.2.42-4 TBl2.26 BRAIs B.2.26-6 and BA6-la B.2.42-4 B.2.42-4 RAIs B.2.26-6 and B.2.26 B-11l2a

Columbia Generating Station License Renewal Application Technical Information Table A-1 Columbia License Renewal Commitments FSAR Enhancement Commitment Supplement or Item Number Location Implementation (LRA App. A) Schedule

25) Fire Protection The Fire Protection Program is an existing program that will be A.1.2.25 Ongoing Program continued for the period of extended operation.

26) Fire Water The Fire Water Program is an existing program that will be continued A.1.2.26 Enhancement Program for the period of extended operation, with the following prior to the period enhancements: of extended

• Perform either ultrasonic testing or internal visual inspection of operation.

representative portions of above ground fire protection piping that Then ongoing.

are exposed to water, but do not normally experience flow, after the issuance of the renewed license, but prior to the end of the current operating term and at reasonable intervals thereafter, based on engineering review of the results.

• Either replace sprinkler heads that have been in place for 50 years or submit representative samples to a recognized laboratory for field service testing in accordance with NFPA 25 recommendations. Perform subsequent replacement or field service testing of representative samples at 10-year intervals thereafter or until there are no sprinkler heads installed that will reach 50 years of service life during the period of extended operation.

" Perform hardness testing (or equivalent) of the sprinkler heads as part of their NFPA sampling, to determine whether loss of material due to selective leaching is occurring.

I - - - -

llnserl A from Page A-51a ___ _ - I lnsert B from Page A-51a I Insert C from Page A-51a Final Safety Analysis Report Supplement Page A-51 JSi'a," 2010 26 2 jAmendment meent

Columbia Generating Station License Renewal Application Technical Information Insert A to Paqe A-51

• Perform ultrasonic testing of representative portions of above ground fire protection piping that is exposed to flowing water during periodic tests, and susceptible to a loss of material due to erosion (wall thinning).

Insert B to Paqe A-51

• Perform visual inspection of a representative sample of copper alloy > 15% Zn Fire Protection components exposed to water for evidence of cracking (presence of ammonia) within the 10-year period prior to entering the period of extended operation (i.e., between year 30 and 40).

• Perform an additional visual inspection of a representative sample of copper alloy > 15% Zn Fire Protection components exposed to water for evidence of cracking (presence of ammonia) within the 10-year period after entering the period of extended operation (i.e., between year 40 and 50).

Insert C to Page A-51

• Address loss of material due to cavitation erosion with activities such as scheduled inspections of the fire protection piping locations that have had indications of cavitation erosion in the past.

Final Safety Analysis Report Supplement Page A-51a [Amendment AMdmnt 2

Columbia Generating Station License Renewal Application Technical Information Insert A into Paqe A-68b FSAR Enhancement Item Number Commitment Supplement or Location Implementation (LRA App. A) Schedule

65) ISI Columbia will prepare and submit the ISI Program Plan for the LRA Appendix -Upon submittal fourth 10-year interval no later than 2015. (The third 10-year B of the IS[

ISI interval extends from December 2005 until December, Program Plan 2015.) The small bore piping program will be included in the for the fourth fourth 10-year interval ISI program plan as an augmented 10-year interval inspection. The locations to be inspected, the sample size, the inspection methodology will be included in the program plan.

66) Structures Perform a one-time internal inspection of the spent fuel pool tell Prior to the period Monitoring Program tale drain lines prior to the period of extended operation to of extended confirm the drain lines are free of obstructions. Unexpected operation.

inspection result of clogged lines will require a condition report be documented and further engineering evaluation of adverse impacts to the spent fuel pool structure and to identify the periodicity of drain cleaning and maintenance process.

67) Structures Perform a one-time boroscope inspection of the containment Prior to 12/31/15 Monitoring Program sand pocket drain lines to confirm the absence of clogged drain lines and that a flow path exists for identification of any potential leakage into the sand pocket region. Unexpected inspection results (clogged drain lines) will be documented under corrective action process.

Insert new row 68 from page A-68d Final Safety Analysis Report Supplement Page A-68c Amendment 22 o 1 jAmendment 26 *'

Columbia Generating Station License Renewal Application Technical Information Insert into page A-68c FSAR Enhancement Item Number Commitment Supplement or Location Implementation (LRA App. A) Schedule

68) Ensure that the condenstate (COND) and reactor feedwater (RFW) Prior to the period systems are screened and evaluated for cavitation prior to entering of extended the period of extended operation (PEO). If the in-scope portion of operation.

either system is determined to be susceptible to loss of material due to cavitation erosion, then a program(s) will be modified or created to manage the loss of material Final Safety Analysis Report Supplement Page A-68d Amendment 26

Columbia Generating Station License Renewal Application Technical Information Insert A to Page B-111

, 3) ultrasonic testing of representative portions of water suppression piping that is exposed to flowing water during periodic tests for evidence of erosion, a4;4 4) copper alloy > 15% Zn components exposed to water and visual inspection of a representative sample of same for evidence of cracking.- -I 1 and 5) inspection of the fire protection piping locations that have had indications of cavitation erosion in the past.

Aging Management Programs Page B-111 a AmR4e4*A92-jAmendment 26 *-ý

Columbia Generating Station License Renewal Application Technical Information Insert A to Paqe B-112 Perform ultrasonic testing of representative portions of above ground fire protection piping that is exposed to flowing water during periodic tests, and susceptible to a loss of material due to erosion (wall thinning). Perform engineering review of the results and trends to determine future inspection intervals and expansion of representative portions, if needed.

Insert B to Page B-1 12 E Scope of Program, Detection of Aging Effects -

Perform visual inspection of a representative sample of copper alloy > 15% Zn Fire Protection components exposed to water (with presence of ammonia) for evidence of cracking within the 10-year period prior to entering the period of extended operation, and within 10 years after entering the period of extended operation.

Address loss of material due to cavitation erosion with activities such as scheduled inspections of the fire protection piping locations that have had indications of cavitation erosion in the past.

Aging Management Programs Page B-112a APe~dM8Rt2 jThendm~tH Ij-