IR 05000280/1991015

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Insp Repts 50-280/91-15 & 50-281/91-15 on 910520-22 & 0619. No Violations Noted.Major Areas Inspected:Isi Including Observation of Visual & Nondestructive Exams on Main Steam Sys Piping Welds
ML20128Q362
Person / Time
Site: Surry  Dominion icon.png
Issue date: 07/08/1991
From:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20128Q347 List:
References
50-280-91-15, 50-281-91-15, NUDOCS 9610210044
Download: ML20128Q362 (7)


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1 neep UNITED STATES

  • o NUCLEAR REGULATORY COMMISSION

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$ j 101 MARIETTA STREET, *

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Report Nos.: 50-280/91-15 and 50-281/91-15

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Licensee: Virginia Electric and Power Company Glen Allen, VA 23060 Docket Nos.: 50-280 and 50-281 License Nos.:

' DPR-32 and DPR-37 Facility Name: Surry I and 2

Inspection Conducted: Ma 20, 22, and June 19, 1991

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Inspector:} /)

L toley & f/

Date signed Accompa i ne - J. J. Blake, June 19, 1991 Approved b .

. . 41ake, Chief 7 /

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Date Signed erials and Processes Section E gineering Branch

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Division of Reactor Safety SUMMARY Scope:

This inspection routine(ISI) unannounced inspection was conducted in the areas of inservice including observation of visual and nondestructive examinations on main steam system piping welds; verification of licensee implementation of NRC Generic Letter 88-05, which required PWR licensees to establish a boric acid prevention program, verification of licensee implementation of NRC Generic Letter 90-05, which provides guidance to licensees for performing non-code repairs of ASME Code Class 1, 2, and 3 piping, and review of Erosion / Corrosion Inspection and Analysis Progra Results:

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In the areas inspected, violations or deviations were nat identifie This inspection indicated that ISI/ nondestructive examinations were conducted adequatel The licensee's assistance was very helpful in assuring that necessary personnel, procedures, and documents were available in a timely manne The inspector identified two inspector followui) items. The first involved a questionable visual inspection on a piping moc'ification, paragraph

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9610210044 910711 '

PDR ADOCK 05000200 G PDR

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2.a. The second involved the 10% acceptance criteria for boric acid corrosion included in Engineering Procedure 84, paragraph 3. At the close of the inspection the licensee was actively investigating the specifics of both items j to determine the possible deleterious affects on reactor plant components and I

to strengthen any programmatic deficiencies identified.

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REPORT DETAILS

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i Persons Contacted i

Licensee Employees i
*R. Bilyeu, Licensing Engineer i
  • H. Collar, Quality Assurance (QA) Supervisor B. Foster, Supervisor, Mechanical Engineering

D. Grady, Nondestructive Examination (NDE) Supervisor j *T. Huber, Inservice Inspection (ISI) Supervisor

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B. Johnson, Mechanical Design Engineering

*M. Kansler, Station Manager

D. Phelps, Mechanical Design Engineering

*J. Price, Assistant Station Manager

. *D. Rogers, Lead ISI Engineer

  • T. Sowers, Superintendent of Engineering

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Other licensee employees contacted during this inspection included craftsmen, engineers, technicians, and administrative personnel.

j NRC Resident Inspector f *J. York, Resident Inspector i

  • Attended exit interview '

' Observation of Visual, Liquid Penetrant, and Magnetic Particle Examinations - Unit 2 i

) The inspector observed the visual, liquid penetrant, and magnetic particle j examinations for four with fabricated in accordance main Work steam system Order (W.0. piping) welds 3800095205 and the that had been

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American National Standards Institute (ANSI) 831.1 Code (1967 Revision). )

{ The four welds are also considered by NRC Reg. Guide 1.26 and the 1980 '

Edition of Section XI, of the ASME Code, to be ASME Code Class 2 welds that

require both preservice and inservice inspections. Examinations for the j following welds were observed:

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Weld ID Methods of Examination

l i' 2-MS-119-18A Visual and Liquid Penetrant 2-MS-119-16A Visual and Magnetic Particle 2-MS-119-17A Visual and Liquid Penetrant 2-MS-119-19A Visual and Liquid Penetrant

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) Visual Exadnation (57050)

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The inspector observed a visual examiner conduct the final visual examinations for the piping modification welds listed above. The initial i

results of the examiner's inspections were that two welds (2-MS-119-16A i

and 2-MS-119-17A) were unacceptable due to surface roughness and that the i l

l other two welds (2-MS-119-18A and 2-MS-119-17A) were acceptable. The

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inspector however, had failed to observe the examiner use any measuring i

devise on either of the welds prior to his annotating the records that the i

final visual inspection for both of these welds were acceptable. In i

addition, the examiner had not brought a copy of the General Welding j Procedure (P-101) to the job in order to determine the proper weld size in accordance with the correct welding specification and the appropriate

material thickness. After being questioned by the inspector concerning i

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the examination, the visual examiner obtained a copy of the General )

i Welding Procedure and weld gages and proceeded to perform satisfactory examinations of the welds in question. All four welds were subsequently

found to be acceptable.

i Futher discussions with' the visual examiner j

indicated that he was convinced that he had performed weld size j

measurements with a welder's six inch scal However, the inspector did

not observed the examiner using the six inch scale until after he had

indicated that the two welds were acceptable.

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The inspector held preliminary discussions with the examiner's supervisor i concerning the above issue on May 22, 1991. However, due to illness the

i inspector was unable to pursue this matter further until June 19, 199 Discussions with the Supervisor of Quality Assurance on June 19th revealed i

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the following:

i i _ ne visual examiner qualification records indicated that he had

significant experience as a visual examiner.

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The quality assurance supervisor issued a memo to all inspection i

personnel on May 24, 1991, reminding them that they are responsible

for determining procedural requiraments, the inspection tools needed, and the proper acceptance criteria to be used prior to going to the job site.

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Virginia Power is presently in the process of performing an audit of all vendor inspection personnel at the Surry and North Anna l i facilities to determine the effectiveness of their vendor examiners l and to improve programmatic control of vendor activitie .

The inspector considers the actions taken by the licensee to date and i

i those presently in-process to be responsible actions on the part Virginia j Power and appropriate for the concern raised by the inspector. Therefore, i

pending review of the licensee's audit findings and additional j

surveillance of inspection activities by the inspector this item will be

$ tracked with Inspector Followup Item No. 50-281/91-15-02, " Visual Inspection of Piping Modification."

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l l 1 Liquid Penetrant Examination (57060)

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j i The inspector observed a nondestructive examination (NDE) examiner perform  !

. liquid penetrant examinations on welds no. 2-MS-119-18A,17A, and 19 t i

The examinations were conducted in accordance with approved procedure n NDE-PT101, Rev.0.

! Discontinuities revealed during the examination were

properly interpreted, evaluated, removed as necessary, and reexamine !

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i The examiner's technical skills, knowledge of procedural requirements, and

. adherence to these requirements were commendable.

. Magnetic Particle Examination (57070)

] The inspector also observed the NDE examiner perform a magnetic particle i

examination of weld no. 2-MS-119-16A. The examination was conducted in

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accordance with the approved procedure (NDE-MT-101 Rev.1). No discontinuities were observed during the examination of this wel The j examiner was proficient in the inspection method.

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Within the areas examined, no violation or deviation was identifie .

! Verification of Licensee Implementation of NRC Generic Letter 88-05 (92701)

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i NRC Generic Letter 88-05, Boric Acid Corrosion of Carbon Steel Reactor i Pressure Boundary Components in PWR Plants, requested licensees to provide i

assurances ensure that that a program has been implemented at their facilities to i

boric acid corrosion due to leakage will not lead to degradation of the reactor coolant pressure boundary. This program is to

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Determination cause significant of the principal locations where leaks may occur and

! boundar boric acid corrosion of the primary pressure '

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Procedures for locating small coolant leaks (i.e., leakage rates at

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less than technical specification limits).

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for conducting examinations and performing engineering

! evaluations leakage is locate to establish the impact on the RCS pressure boundary when

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Corrective action to prevent recurrences of this type of corrosio ;

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This response , basically statedthe that,licensee forwarded the Surry Power Station their letter has of response to N j procedural controls in place to accomplish each of the above NRC program

concerns. On May 22,1991, the inspector audited the licensee's program to 4 verify the adequacy of the boric acid prevention program in place. The j inspector found the licensee's program to be adequate with one possible exceptio ENG-84, - dated This exception was found in Surry's Engineering Procedure N December i

10,1987, and entitled, " Evaluation of Safety l

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Related Components with Excessive Boric Acid." Paragraph 5.8 of this procedure sets a Go/No-Go acceptance criteria of 10% for depth of

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corrosion on all reactor plant components. Although, 10% sounds i

reasonable for standard components, there are some reactor coolant components such as the reactor main coolant pumps (MCP) bolts and the t reactor vessel studs that are manufactured to critical drawing tolerance A l i

recent experience with boric acid corrosion on MCP bolts at another j utility revealed that the suggested bolt acceptance criteria, after

material lost due to corrosion, was much more stringent than the 10%

delineated in Engineering Procedure 84. The acceptance criteria on these i l'

i components are also low because even minor leakage on these components can

! cause corrosion rates of .400 inch per month and therefore serious damage can occur on these bolts between outages. The inspector held discussions '

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j with cognizant licensee personnel concerning notifying the equipment vendor and acquiring a list of components where the 10% acceptance

criteria would be inadequate. Inaddition, the licensee should seek i

i guidance from the vendor in establishing an appropriate acceptance criteri The licensee's actions regarding resolution of this issue will be tracked by Inspector Followup Item 50-280,281/91-15-01, " Acceptance

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i Criteria for Boric Acid Corrosion on Reactor Coolant Boundary Components."

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Within the area examined, no violation or deviation was identified.

j 4 4 Review of Licensee's implementation of NRC Generic Letter 90-05, " Guidance for performing Temporary Non-Code Repair of ASME Code Class 1, 2, and 3 l piping" (92701)

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The inspector held discussions with the Lead ISI Engineer to determine if i the guidance for performing temporary non-code repairs of ASME Code piping j

had been implemented in procedures at Surry. Procedural implementation of the Generic Letter Guidance is important in that it ensures programmatic

! criteria exist for these important repair activitie The discussions revealed that Virginia Power is presently revising Procedure No. VPAP-037, which is utilized for the repair and replacement of ASME Section XI components, to implement Generic Letter 90-05. The effective date for issuance of the revised procedure is August 1,199 Within the area examined, no violation or deviation was identifie .

Review of Erosion / Corrosion Inspection and Analysis Program (92701)

On June 19, 1991, the inspector reviewed the licensee's programs for -

erosion / corrosion inspection and analysis. The review was conducted by ~

interviewing the responsible personnel in the site Mechanical Design Engineering Grou The purpose of the review was to determine the scope of the site program for inspecting, testing, analyzing, and predicting erosion and erosion / corrosion problems at Surr The personnel interviewed were able to describe and trace the history of the inspection and analysis program at Surry and demonstrate the analysis procedures that are currently being use .-

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' The site uses programs that were developed in conjunction with EPR These programs are CHEC-NDE which is the inspection program, and CHEC and l

CHECMATE which are the modeling programs for single phase flow and i

two-phase plus chemistry. The site people further explained that they i

receive guidance and direction for the site inspection and analysis programs from a corporate engineering group located at the Innsbrook l Technical Center.

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This review showed that Virginia Power Co. has a very comprehensive program at for the the Surry inspection and analysis of erosion / corrosion of the piping station.

This program should provide sufficient warning to i

preclude another catastrophic failure at Surry. The scope of work that is

ongoing at Surry includes the replacement of carbon steel piping i

components with chrome-moly alloy steel whenever the inspections indicate that there is significant, flow-related, wall reductions.

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There were no violations or deviations identified during this part of the inspectio l

} Exit Interview

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The inspection scope and results were summarized on June 19, 1991, with l those persons indicated in paragraph 1. The inspector described the areas

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inspected and discussed in detail the inspection results listed belo Proprietary information is not contained in this repor Dissenting comments were not received from the licensee.

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i (0 pen) Inspector Followup Item 50-280,281/91-15-01, " Acceptance Criteria 1 for Boric Acid Corrosion on Reactor Boundary Components," paragraph 3

i (0 pen) Inspector Followup Item 50-281/91-15-02, " Visual Inspection of Piping Modification," paragraph :

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