IR 05000298/1997004

Insp Rept 50-298/97-04 on 970407-11 w/in-office Insp Continuing Until 970421.No Violations Noted.Major Areas Inspected:Insp Consisted of Review of Licensee Planned & Implemented Activities Associated W/Erosion Program

ML20148B199
Person / Time
Site:	Cooper
Issue date:	05/06/1997
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
Shared Package
ML20148B190	List: IR 05000298/1997004 ML20148B185
References
50-298-97-04, 50-298-97-4, NUDOCS 9705120262
Download: ML20148B199 (16)

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ENCLOSURE U.S. NUCLEAR REGULATORY COMMISSION

REGION IV

Docket No.: 50-298 License No.: DPR-46 Report No.: 50-298/97-04 Licensee: Nebraska Public Power District Facility: Cooper Nuclear Station l Location: P.O. Box 98 Brownville, Nebraska Dates: April 7-11,1997, with iPoffice inspection continuing until April 21, 1997 Inspector: Clifford A. Clark, Reactor Inspector, Maintenance Branch Division of Reactor Safety l Approved By: Dr. Dale A. Powers, Chief, Maintenance Branch Division of Reactor Safety .

. ATTACHMENT: Supplemental Information

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9705120262 970506 PDR ADOCK 05000298 O PDR

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EXECUTIVE SUMMARY

! Cooper Nuclear Station

] NRC Inspection Report 50-298/97-04 i

This inspection consisted of a review of the licensee's planned and implemented activities I

associated with the erosion / corrosion monitoring program and the inservice inspection

! program. The inspection report covers a 1-week period on site, with followup in the office j performed by one region-based inspecto Maintenance

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Licensee reviews in 1993,1994, and 1995 failed to properly account for l erosion / corrosion monitoring program results of service water system degradation.

As a result of these oversights, Diesel Generator 1 became inoperable when a leak l

' occurred in its lube oil cooler (Section M1).

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Erosion / corrosion and inservice inspection procedures and records were adequately developed for the identified tasks. Examination personnel and equipment were properly certified (Sections M3.1 and M3.2).  ;

Erosion / corrosion and nondestructive inservice inspector examinations were properly performed by knowledgeable contract personnel (Sections M4.1 and M4.2).

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-3-Report Details Summary of Plant Status The unit was in Mode 5 for Refueling Outage RFO17 during this inspection perio ii. Maintenance M1 Conduct of Maintenance i l Inspectiors Scope (49001)  !

The inspector reviewed the information available on a February 28,1997, failure of service water piping to Diesel Generator 1 lube oil heat exchange Observations and Findinas The inspector reviewed the information and noted that on February 28,1997,a pinhole leak (a self-disclosing condition) was discovered in service water piping to the lube oil heat exchanger for Diesel Generator 1, and the generator was declared inoperable. The leak occurred in a 6 by 8-inch reducer downstream of Air -

Operated Valve SW-AOV-2797AAV, and was documented in Problem. identification Report 2-12489. The problem identification report was not, however, classified as a condition adverse to qualit The f ailed reduce was being monitored in the licensee's erosion / corrosion program under the microbiologically-induced corrosion inspection scope. The applicable j erosion / corrosion program identification for this reducer was SW-DG-1-R-2. The i following background information was provided for the inspector's review:

• The reducer was replaced in 1991 as a result of a similar leakage, i

• Ultrasonic thickness examination was performed on the reducer during the -

1993 refueling outage. Wall thinning was identified, and the component was )

evaluated by design engineering for structural integrity. As a result of an !

inadequate review, the 1993 design engineering evaluation did not recognize ;

the .1991 replacement of the reducer and, therefore, used a calculated 14.22 years for the time that the component had been inservic * In May 1994, a review of the calculated operating years for service water components was performed. The review identified the 1991 replacement of the subject reducer. The updated calculated operating years was forwarded I to design engineering for incorporation into the service water pipe stress calculation performed for erosion / corrosion considerations. As a result of an

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inadequate review, the updated operating years determination was not incorporated into the results of the calculation. Based upon the change in calculated operating time, the reducer wall thinning rate should have been increased from 0.013 to 0.083 inch per yea * The reducer structural integrity was reviewed in 1995, to verify readiness for startup from the 1994 1995 unscheduled shutdown. As a result of an inadequate review, this evaluation used the originally-provided, erroneous wear rate of 0.013 inch per year, and concluded that the remaining service life would be an additional 12.3 year * Unfortunately, the reducer was omitted from the 1995 outage erosion / corrosion inspection scope based upon the information provided in the 1995 evaluatio The licensee evaluation of this reducer failure noted the following:

• Multiple protection barriers (i.e., missed opportunities) were broken, which resulted in the failure to determine the need to replace the reducer prior to its developing a through-wall lea * The failures of these protection barriers indicated a lack of consistent program ownership. The erosion / corrosion program experienced significant turnover of program ownership in the period from 1993 through August 1996. Compounding the inconsistency in the program ownership was the early stage of development of the microbiologically-induced corrosion monitoring element for the service water system. Further, microbiologically-induced corrosion monitoring for the service water system had been based solely upon maintenance experience and engineering judgement. This was because the licensee was not aware of any suitable predictive model available for industry use for service water application The inspector reviewed recent licensee corrective actions implemented for this reducer failure and noted the following:

• The affected reducer was replaced, and Diesel Generator 1 was returned to an operable status. Additional service water components in Diesel Generator 1, and similar components in Diesel Generator 2, were ultrasonically examined to ensure there were no similar degradation * A Problem identification Report 2-12502 was issued upon discovery that some components adjacent to the failed reducer also contained areas of wall thinning. This condition was identified during the replacement of the failed reducer. These components were subsequently either evaluated acceptable or identified for replacement during the current 1997 refueling outag \

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The 1997 erosion / corrosion inspection scope was reviewed by the licensee to ensure that microbiologically-induced corrosion examinations of the service water system had not been inappropriately omitted. Subsequently, all microbiologically-induced corrosion examinations of the service water i system were found to have been included, i

The wear rate calculations for the service water system were reviewed by !

the licensee to ensure that they adequately reflected known replacement l history for affected components. No additional component replacements j were found which had not already been incorporated into the wear rate calculation The inspector noted that the licensee had implemented the following actions to prevent recurrence:

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• The vacant erosion / corrosion program owner position had been fille i

• Tools for a more effective program management had been establishe !

These tools included the erosion / corrosion program document and an

, inspection database. The licensee representative stated these tools were i flexible enough to grow with the program, and provide a basis to ensure consistency in the program in the event of a future turnover of the program owne Based on available information, the inspector could not determine the scope of this implementation problem with the erosion / corrosion monitoring program and the adherence to the requirements for reporting quality-related problems. This is an unresolved item pending further NRC review (50-298/97004-01). Conclusions Licensee reviews in 1993,1994, and 1995 failed to proporly account for erosion / corrosion monitoring program results of service water system degradatio As a result of these oversights, Diesel Generator 1 became inonerable when a leak occurred in its lube oil coole M3 Maintenance Procedures and Documentation M 3.1 Review of Erosion / Corrosion Monitorina Certifications, Procedurss, cnd itucurds Insoection Scope (49001)

The inspector interviewed licensee and contract personnel involved in erosion / corrosion activities. The inspector also reviewed the erosion / corrosion monitoring documents, completed Refueling Outage RFO17 erosion / corrosion examination records, and contractor equipment and personnel certification record _ _ - _ _ _ _ ___ _-_-

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6-b. Observations and Findinas The licensee's "1997 Pipe Monitoring inspection Scope," recommended inspecting a total of 215 components for the vt.rious pipe wall monitorng efforts at Cooper Nuclear Station. The specific programs and areas of concer1 and the number of recommended component inspections were as noted below:

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• Erosbn/ corrosion program - 96 components

• Augmented erosion / corrosion program - 17 components

• Components downstream of throttling devices - 18 components

• Microbiologically-induced corrosion program - 72 components

• Small bore piping - 12 components As of March 10,1997, the scope of components scheduled to be examined during the current Refueling Outage RFO17 for the various pipe wall monitoring efforts, had increased (as a result of further licensee reviews) to 235 component The inspector found that in the last year the licensee used the Electric Power Research Institute's Checworks f amily of codes, along with otner industry information and experience, to identify and rank suspected locations in piping systems for the Refueling Outage RF017 erosion / corrosion inspections. The inspector noted that the licensee had modeled 1076 components in a Checworks database, which was currently undergoing an offsite independent 'fication of data input. The licensee representative identified that the following systems were included in the Checworks database:

• Condensate

• Turbine cross-under piping

• Extraction steam

• Heater drains

• Reactor feedwater

• Reactor water cleanup l

l The inspector determined that contractor equipment and personnel certification records were complete and current. Refueling Outage RFO17 erosion / corrosion examination data packages identified approximately 20 data packages available as of March 10,1997. The inspector found them to be complete (for the stage of development they had undergone).

c. Conclusions The inspector concluded that erosion / corrosion records and procedures were adequate for the identified tasks. Examination personnel and equipment were properly certified in accordance with procedure requirement ____-____- _ ________ _ -

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M3.2 Review of inservice Inspection Certifications, Procedures, and Records Insocction Scope (73753)

The inspector reviewed the inservice inspection documents and equipment and personnel certification records. The inspector also interviewed contract and licensee personnel.

l l Observations and Findinos The inservice inspection examinations were scheduled to be performed in Refueling Outage RF017 in accordance with the ASME,Section XI, " Inservice Inspection Program Plan," the first inspection of the first 40 month period of the third Ten-Year j interval. The inservice inspection program plan was written in accordance with the requirements of the 1989 Edition of Section XI of the ASME Boiler and Pressure l Code, no addenda. The inspector found that the documents (procedures, records,

! and reports) had been developed in accordance with licensee procedures, regulatory requirements, and applicable ASME Code requirement '

t The inspector determined the contractor equipment and personnel certification records were complete and current. The various Refueling Outage RFO17 inservice )

inspection examination records available March 10,1997, were found.to be j complete (for the stage of development they had undergone). j Conclusions l l

l The inspector concluded that the inservice inspection procedures and records were l adequate for the identified tasks. The inspector found the equipment and examiners ,

l were properly certified in accordance with ASME Code requirement l l

l M4 Maintenance Staff Knowledge and Performance j i

M4.1 Erosion / Corrosion Staff l Inspection Scone (49001)

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i The inspector observed contract personnel perform erosion / corrosion ultrasonic thickness examinations of condensate and extraction steam piping. The inspector ,

assessed licensee and contract personnel knowledge and performance in this are '

i Observations and Findinas

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As a result of a licensee management decision to stop site work in order to conduct '

i briefings on safe work practices, there were a limited number of erosion / corrosion examinations available for inspector observation.

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The inspector observed ultrasonic thickness examinations property performed i by qualified nondestructive examination personnel on Condensate Piping

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Components CH E-9-2819-6 and CH-R-4-2819-4, and Extraction and Bleed Steam Component BS-A-18-2812- ,

i Conclusions The inspector concluded that the observed erosion / corrosion ultrasonic t examinations were performed in accordance with the appropriate procedures by  ?

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M4.2 inservice Insoection Staff I t insoection Scope (73753) l l

The inspector observed inservice inspection examinations and assessed the contract and licensee personnel knowledge and performance in this area, Observations and Findinas As a result of the management decision to stop site work, there were a limited

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number of inservice inspection examinations available for inspector observation.

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The inspector observed a magnetic particle examination performed by qualified nondestructive examination personnel on Main Steam Piping Weld RAS-CF-14 (Report R 120). Conclusions The inspector concluded that the observed nondestructive examination was performed in accordance with the appropriate procedure by knowledgeable contract personne M8 Miscellaneous Maintenance issues (92902)

M8.1 (Closed) Violation 50-298/95015-01: Failure to Establish Reference Svstem for Welds

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The inspecturs, while observing 1995 nondestructive examinations of Section XI repair / replacement activities on welds, discovered that some welds installed during the second 10-year interval of the inservice inspection program had not  ;

been phvsically marked in ac

ordance with the requirements of Appendix IV of )

l Section XI. The 1980 ASME Code, Winter 1981 Addenda,Section XI, Mandatory l Appendix Ill, Article 111-4000, Paragraph 111-4330, stated, in part, "[clircumferential ;

welds in Class 1 and 2 piping requiring volumetric examination shall be marked [in ;

i reference to weld centerline) once before or during'preoperational examination to l

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establish a reference point." Since preservice examination was not performed at <

Cooper Nuclear Station, existing welds were excluded from this requirement and before 1991, there was no reference system, including perrnanently marking for determining the actual centerline of welds at Cooper Nuclear Statio The licensee initiated Condition Report 95-1192 to address this inspector-identified I deficiency. The licensee reviewed the docementation of examinations performed on I repair / replacement welds during the second 10-year inservice inspection interval.

l The licensee found that those welds which had not been marked at one time during l the second 10-year interval had subsequently been either replaced arJ appropriately marked, or were reconciled as no longer requiring marking in accordace with Section XI Code requirements. The licensee representative noted that a contributing l factor to not marking the welds may have been the lack of adequate technical l knowledge of ASME Section XI in 1984, when the second 10-interval inservice inspection program was developed. The licensee representative noted that since that time, an experienced inservice inspection engineer had been hired.

The inspector interviewed personnel, reviewed documentation, and verified that l adtninistrative controls were in place in Procedures 0.30, "ASME Section XI l Repair / Replacement and Temporary Non-Code Repair Pro;adure," Revision 11, anJ l 3.28.1.2, "Wrid Preparatior, and Marking for ISI," Re. vision 1 C1, to ensure future

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repair / replacement welds were appropriately marked for inservice inspectio i M8.2 (Closed) Violation 50-298/95015-02: Failure to initiate a Condition Report l Calibration blocks from the Duane Arnold Nuclear Plant were shipped to Cooper !

l Nuclear Station for use in performing inservice inspection program examination The licensee's inservice inspection staff temporarily lost control of them prior to the engineering department's inspection acceptance and release. During that time, the calibration blocks were used by contractor technicians to calibrate and perform ultrasonic examinations. This happened despite the inservice inspection coordinator informing the contractor technicians not to use the blocks until the engineering department had verified the blocks were within acceptable tolerances and released them for use. Even though these calibration blocks were identified by the licensee's engineering department, a condition report was not prepared to document and ( correct this deficiency until the inspector discussed this issue with licensee personnel. This failure to initiate condition reports had been a continuing problem at

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l Cooper Nuclear Station, j The licensee initiated Condition Report 95-1109 to address this deficiency involving l

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the lack of control over calibration blocks. The licensee identified that the personnel involved in this issue were reinstructed as to the expectation that the condition report process was to be used to document potential conditions adverse to quality.

, Additionally, this issue was described to licensee personnel in a posted newsletter on outage progress and activities.

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l The inspector interviewed personnel, reviewed documentation, and verified that identified corrective actions had been accomplishe V. Manaaement Meetinas

X1 Exit Meeting Summary

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The inspector presented the inspection results to members of licensee management at the conclusion of the inspection. The licensee personnel acknowledged the findings presente The inspector asked the licensee personnel whether any materials examined during the inspection should be considered proprietary. No proprietary information was identified.

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I' ATTACHMENT l

SUPPLEMENTAL INFORMATION PARTIAL LIST OF PERSONS CONTACTED Licensee Terry Ackerman, Engineer, inservice Inspection Michael Bennett, Supervisor, Licensing Michael Boyce, Manager, Engineering Special Projects Bradford Houston, Manager, Licensing David Madsen, Senior Engineer, Licensing James Pelletier, Senior Manager, Engineering Michael Spencer, Supervisor, Engineering Programs NRC Mary Miller, Senior Resident inspector

.Chris Skinner, Resident Inspector INSPECTION PROCEDURES USED IP 49001 Inspection of Erosion / Corrosion Monitoring Programs IP 73753 Inservice inspection IP 92902 Followup - Maintenance  !

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ITEMS OPENED AND CLOSED

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( Opened 50-298/97004-01 URI Problem in the implementation of the erosion / corrosion monitoring progra Closed 50-298/95015-01 VIO Failure to establish reference system for weld /95015-02 VIO Failure to initiate a condition report.

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-2-LIST OF DOCUMENTS REVIEWED Procedure Revision Title 1'

. O.30 11 "ASME Section XI kepair/Replacemert and Temporary Non-4 Code Repair Procecure" i

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3.10 "Examinatior and Evaluation of Pipe Wall Thinning"

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3.28 2 " Inservice Inspection and Testing Programs"

3.2 " Inservice inspection Program implementation" 3.28. "Visualinspection of Pressure Retaining Bolting and Integral Attachments, VT-1" 3.28. C1 " Weld Preparation and Marking for ISI" UT-CNS-102V1 0 " Procedure for Manual Ultrasonic Examination of Similar and Dissimilar Metal Piping Welds" UT-CNS-104VO 2 " Procedure for Manual Ultrasonic Planar Flaw Sizing" UT CNS-106V1 0 " Procedure for Manual Ultrasonic Examination of Ferritic Piping 1

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and Vessel Welds 2" and Less in Thickness" GE-ADM 1001 0 " Procedure for Performing Linearity Checks on Ultrasonic Instruments" Erosion / Corrosion Outaae Reoorts

" Piping Wall Thickness Monitoring Program Spring 1993 Outage Inspection Report,"

dated Marcn 17,1996

" Piping Wall Thickness Monitoring Program Fall 1995 Outage Inspection Report,"

dated March 17,1996 inservice inspection Audit QA Audit 95-23, " Inservice . Inspection," dated January 17,1996 Contractor Eouloment/ Examiner Certifications Erosion / Corrosion - Sonic Systems International, In Inservice inspection - GE Nuclear Energy l

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Condition Reports

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.i 4-CR 95-1192 CR 97-0284 Problem identification Report 2-12489 2-12502 Other Documents

" Cooper Nuclear Station Erosion / Corrosion Monitoring Program," dated January 10,1996

"1997 Pipe Monitoring inspection Scope," (no date of issue)

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ATTACHMENT SUPPLEMENTAL INFORMATION PARTIAL LIST OF PERSONS CONTACTED

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Licensee

Terry Ackerman, Engineer, inservice Inspection 1 Michael Bennett, Supervisor, Licensing '

Michael Boyce, Manager, Engineering Special Projects Bradford Houston, Manager, Licensing David Madsen, Senior Engineer, Licensing James Pelletier, Senior Manager, Engineering i Michael Spencer, Supervisor, Engineering Programs i

. NRC Mary Miller, Senior Resident inspector

Chris Skinner, Resident inspector j INSPECTION PROCEDURES USED l

' i IP 49001 Inspection of Erosion / Corrosion Monitoring Programs l

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IP 73753 Inservice inspection i IP 92902 Followup - Maintenance

ITEMS OPENED AND CLOSED Opened 50-298/97004-01 URI Problem in the implementation of the erosion / corrosion monitoring progra Closed l 50-298/95015-01 VIO Failure to establmh reference system for weld /95015-02 VIO Failure to initiate a condition repor _ _ . _ _ _ _ _ _ _ _ __ _ _ . _

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-2-LIST OF DOCUMENTS REVIEWED Procedure Revision Title  ;

0.30 11 "ASME Section XI Repair / Replacement and Temporary Non-Code Repair Procedure" 3.10 " Examination and Evaluation of Pipe Wall Thinning i

3.28 2 " Inservice inspection and Testing Programs"

3.2 " Inservice inspection Program Implementation" l

3.28. " Visual inspection of Pressure Retaining Bolting and integral Attachments, VT-1" 3.28. C1 " Weld Preparation and Marking for ISI" l

UT-CNS-102V1 O " Procedure for Manual Ultrasonic Examination of Similar and i Dissimilar Metal Piping Welds" )

UT-CNS-104VO 2 " Procedure for Manual Ultrasonic Planar Flaw Sizing" l

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UT-CNS-106V1 0 " Procedure for Manual Ultrasonic Examination of Ferritic Piping j and Vessel Welds 2" and Less in Thickness" I GE ADM-1001 0 " Procedure for Performing Linearity Checks on Ultrasonic Instruments" Erosion / Corrosion Outaae Reports

" Piping Wall Thickness Monitoring Program Spring 1993 Outage inspection Report,"

dated March 17,1996

" Piping Wall Thickness Monitoring Program Fall 1995 Outage inspection Report,"

dated March 17,1996 Inservice insoection Audit QA Audit 95 23, " Inservice Inspection," dated January 17,1996 Contractor Eauioment/ Examiner Certifications Erosion / Corrosion - Sonic Systems International, In Inservice Inspection - GE Nuclear Energy

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Condition Reports CR 95-1109 CR 95-1192 l

CR 97-0284 Problem Identification Report j

2-12489  !

2-12502 Other Documents

" Cooper Nuclear Station Erosion / Corrosion Monitoring Proarsm," dated January 10,1996 I

"1997 Pipe Monitoring inspection Scope," (no date of issue) i l

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