IR 05000412/1993021

Insp Rept 50-412/93-21 on 930830-0903 & 1004-08.No Violation Noted.Major Areas Inspected:Isi Program,Scope of ISI Work, Eddy Current Exam Program for SG Tubes,Erosion/Corrosion Monitoring Program for High Energy Sys & SG Leakage Program

ML20059G324
Person / Time
Site:	Beaver Valley
Issue date:	10/22/1993
From:	Michelle Beardsley, Modes M, Patnaik P NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20059G323	List: IR 05000412/1993021 ML20059G320
References
50-412-93-21, NUDOCS 9311080067
Download: ML20059G324 (8)

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U. S. NUCLEAR REGULATORY COMMISSION

REGION I

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REPORT / DOCKET NOS. 50-412/93-21 LICENSE N NPF-73 i LICENSEE: Duquesne Light Company Post Office Box 4  ?

Shippingport, Pennsylvania 15077 FACILITY NAME: Beaver Valley Power Station, Unit 2

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INSPECTION DATES: August 30 - September 3 and October 4-8,1993 INSPECTORS: b bbhi - lo/.B /H

' Date C. Beardslee, Reactor Engineer Materials Section, EB, DRS

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f. PO t%'m t o 2.2. 9 3 P. Patnaik, Reactor Engineer Date Materials Section, EB, DRS APPROVED BY: _/fs f/M // f7'

iiichael C. Modes, CiiiF ~ ' Date Materials Section, EB, DRS 93110 DR BOO 67 931101 ADDCK 05000412 PDR

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Areas Inspected: Review of inservice inspection (ISI) program, scope of ISI work, eddy :

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current examination program for steam generator tubes, erosion / corrosion monitoring program for high energy systems and steam generator leakage monitoring progra Results: Licensee's ISI program and the scope of ISI work for the fourth refueling outage '

complied with the 1983 edition of ASME Code Section XI including the summer '83 addendum. The steam generator tube examination met the requirements of the technical ..

specification. The erosion / corrosion monitoring program, however, lacked the use of any I predictive methodology in selection of components for thickness examination and the number of components examined appeared to be small in relation to the total population to assure a high degree of confidence in erosion / corrosion evaluations. The limiting leak rate of 7

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250 gpd prior to power reduction during a primary-to-secondary leak should be evaluated to assess conservatism against potential tube rupture in the presence of an active degradation mechanis :

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. J DETAILS INSERVICE INSPLCTION (ISO (73753) Scope i

The conduct of inservice inspection using ultrasonic, magnetic particle and liquid penetrant examination ensures integrity of the pressure boundary. During this inspection, reviews of 3 j

the ten-year ISI plan, the scope of work for the outage, a sampling of inservice inspection ;

data, and observation of work activities were performed to ascertain if the requirements of the applicable ASME Code,Section XI, and the technical specifications were me .2 Findings Duquesne Light Company (DLC), the licensee for Beaver Valley Unit 2, conducted an

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inservice inspection during the fourth refueling outage of the unit in accordance with the ASME Code,Section XI,1983 edition, including the summer 1983 addendum. The unit is in the second inspection period of the Hrst inspection interval and the ongoing outage (fourth .

refueling) is the last outage of the second period. The inspector reviewed the ten-year ISI plan and the relief requests to the NRC on welds which are impractical to examine in accordance with the applicable code. Within the scope of the review, the inspector did not Gnd any discrepanc l The inspector reviewed the scope of inservice inspection work for the outage. The components listed in the work scope were identi6able from the ten-year plan. The examination requirement for each component complied with that of the applicable ASME ,

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Code,Section XI. The percentage of welds examined by the end of the second period also i

met the speciGed percentage of the 1983 ASME Code,Section X !

The inspector performed surveillance of the storage area for the ultrasonic calibration block ]

The storage facility appeared to be adequate. The general condition of the calibration blocks with regard to corrosion, is good. The quality services department (QSD) personnel performed routine surveillance of NDE activities during inservice inspection. The level of '

i stafHng to implement the inservice inspection program was found to be adequat ;

During ultrasonic examination of girth weld No. 8 on "B" steam generator, two indications '

were recorded which were subsequently characterized for shape, size and geometry by the licensee's nationally certified American Society of Nondestructive Testing level III

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personnel. The inspectors witnessed the ultrasonic scan of the weld and concurred with the licensee's disposition of the indication as stated belo !

• The indication #200 was verified using a 45 degree search unit and was believed to be a welded attachment or a pad on the vessel inside surface k>cated outside the weld examination volum l

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• The indication #400 was verified using a 60 degree search unit to be a spot indication with little length or throughwall depth. This indication was plotted to fall outside the weld and is believed to be a laminar non-metallic inclusion. The inspectors also reviewed the construction radiograph to confirm this indication. The radiograph, however, did not show any indication at the area of concer Both indications were considered acceptable in accordance with the applicable ASME Code Section X .3 Conclusion The licensee exercised adequate control over inservice inspection activities during the fourth ;

refueling outage of Beaver Valley Unit 2. The inservice inspection program, during the outage, was found to be in compliance with the applicable ASME Section XI Code and the regulatory requirement .0 LONG-TERM EROSION / CORROSION (E/C) MONITORING (49001)

The inspector reviewed the scope of work during the fourth refueling outage as regards E/C monitoring of components in the high energy sys* ems. The licensee selected twenty components (twelve were previously examined) for erosion / corrosion monitoring during the current outage. The selection of components was primarily based on operating experience, industry experience and engineering judgemen The inspector expressed concern that the number of components selected by the licensee for E/C examination was small in relation to the total component population and was below the number of components typically examined at other plants. The inspector was also concerned -

that the licensee did not use any of the predictive methods available to the industry in ranking of components susceptible to erosion / corrosion. The licensee stated that the unit has operated exclusively on morpholine pH control since startup and firmly believes that the unit has experienced virtually no measurable erosion / corrosion due to maintaining a high pH chemistry with morpholine. The licensee, however, expressed their intent to perform a systematic review of systems susceptible to E/C using the EPRI recommended computer model "CHECMATE" starting with the feedwater syste Based on the results of the analysis, additional components will be examined for erosion / corrosion during the outage. The inspector requested the licensee's tentative plan and schedule for erosion / corrosion analysis and examination of components in other susceptible systems during upcoming outage a

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5 STEAM GENERATOR EDDY CURRENT EXAMINATION (73753)

The steam generator (SG) eddy current examination of Beaver Valley Unit 2 was in progress during the inspection. The licensee planned to perform bobbin coil examinations of 100 percent of the tubes in each steam generator. Additional examinations using the rotating pancake coil (RPC) were also planned as follow * 150 tubes in the tubesheet in each steam generator

• All Row I and Row 2 U-bends in each steam generator (approximately 186 per S/G)

• All distorted signals from the support plates  ;

During this inspection, the licensee's data acquisition and so ; e resolution of data due to

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differences between the primary and the secondary analysis were witnessed. These activities were performed in accordance with the licensee's procedure and the data analysis guidelin ,

During the inspecdon, the following procedures were reviewed: ,

• Multifrequency Eddy Current Examination of 0.875 in. OD x 0.050 in, wall tubing in Westinghouse RSGs using the M1Z-18/18A (Procedure ISI-428, Rev. 5) j l

• Technical Procedure for the Evaluation of Eddy Current Data for Debris, Sludge and l Secondary Side Loose Parts in Steam Generators (Procedure ISI-462, Rev. 5) )

• Administrative Procedure for Processing NDE Data (Procedure ISI-69, Rev.18)

• Administrative Procedure for the Written Practice of Personnel Qualification in Eddy !

Current Examination (Procedure ISI-24, Rev.16)

• Unit #2 - Steam Generator Analysis Guidelines (Procedure ISI-El-8, Rev. 2)

The inspector determined from the review that the above procedures and the data analysis j

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guidelines meet the applicable ASME Code and the industry standards. The personnel

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performing the eddy current examination were appropriately certified in accordance with SNT-TC-1 A,1980, requirements. level IIA and level III personnel, who are qualified to perform analysis of eddy current results, were trained on the Unit 2 site specific steam generator tube materials and conditions, and on the " Unit 2 - Steam Generator Analysis Guidelines." Also, prior to the start of eddy current testing, these personnel took a written and practical examination to demonstrate their site specific knowledge and eddy current

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analysis capabilitie i

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6 Conclusions

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For those areas inspected, the eddy current examination program met the industry standards and the regulatory requirement . STEAM GENERATOR LEAKAGE MONITORING, UNIT 1 The licensee's primary-to-secondary leak rate monitoring program as outlined in j BVPS-1/BVPS-2 Chemistry Manual 5.12 was reviewed. The program for Unit 1' addresses ;

specific actions to be taken to prevent rapidly propagating fatigue cracks from causing a ;

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steam generator tube rupture event. This program was implemented in response to NRC BuHetin No. 88-02, " Rapidly Propagating Fatigue Cracks in Steam Generator Tubes."

During this inspection, the inspector reviewed chemistry logs pertaining to blow down and s

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condenser air ejector radiation monitors for isotopic activity. It was noted that the licensee has routinely sampled each steam generator three times per week to detect the presence of a primary-to-secondary leakag ,

In addition to effluent monitoring, Beaver Valley Unit 1 incorporates an N-16 steam generator leak monitoring system which is based on the detection of radioactive N-16 in the ;

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steam. Each main steam line is monitored by a detector and an associated microprocessor to provide a means to calculate a steam generator leak rate in gallons per day. - The inspector reviewed "Radcon Instrument Procedure 2.30," on the N-16 steam generator leak monitoring system and had no commen l During review of the licensee's primary-to-secondary leak rate monitoring program as outlined in Chemistry Manual 5.12, the inspector questioned the conservatism of the limiting ;

leak rate of 250 gallons / day prior to reducing plant power to fifty percent within one hou ;

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The steam generator tubes in Unit I have experienced some limited denting at the top support plate, along with an active tube degradation mechanism of stress corrosion in the outer ;

surface. In regard to some of the recent tube failures at other plants, the inspector requested j the licensee to reevaluate the limiting leak rate prior to reducing power to fifty percent in !

order to prevent tube rupture due to a rapidly propagating fatigue crack or a stress corrosion

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t i MODIFICATION TO AUXILIARY FEEDWATER SYSTEM (55050) 1

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The inspectors reviewed several aspects of a major modification (#2002) to the auxiliary feedwater system, which, in part, consisted of replacing / relocating several valves. The l 10 CFR 50.59 safety evaluation, which was found to be adequate, and radiographs of several' :l ASME Class 2 welds were reviewed. The inspector noted tha' the initial weld reject rate i appeared to be high, but there were no major concerns because the welds were consequently ,

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l repaired and found to be acceptable for service. The inspector also observed welding being .

performed as part of this modification. The weld data sheet, weld map, and welding

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procedure were reviewed and found on location as required. In addition, quality control hold points were being adhered to and quality assurance involvement was eviden ' ENTRANCE AND EXIT MEETINGS

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Members of the licensee's management, engineering, and technical staff were informed of-i the scope and the purpose of the inspection at the entrance meeting which took place on August 30,1993. The findings of the inspection were presented to and discussed with members of the licensee's management at the exit meetings on September 3,1993, and October 8,1993. The licensee concurred with the findings of the inspection and did not voice any objections. A list of attendees of the exit meeting on October 8,1993, is attached to this report as Attachment ;

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i ATTACIIMENT I Duauesne Licht Company

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G. Alberti ISI Coordinator A. Dulick Manager, Chemistry ,

J. Finke Sr. Engineer J. Giocondi NDE Supervisor K. Grada Manager, QSU *

G. Kammerdeiner Director, Materials Engineering A. Mossa Sr. QA NDE Specialist i

T. Noonan General Manager, Nuclear Engineering & Safety D. Orndorf Chemistry Operations Director i

M. Pergar Director, Quality Services B. Sepelak Licensing Engineer J. Sieber Sr. Vice President and CNO W. Sikorski Director, ISI D. Spoerry Division Vice President - Nuclear Operations i

G. Thomas Division Vice President - Nuclear Services N. Tonet Manager, Nuclear Safety i

U.S. Nuclear Reculatory Commission (USNRC)

C. Beardslee Reactor Engineer

P. Patnaik Reactor Engineer L. Rossbach Senior Resident Inspector  ;

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