IR 05000259/1988012

Insp Repts 50-259/88-12,50-260/88-12 & 50-296/88-12 on 880502-06.No Violations or Deviations Noted.Major Areas Inspected:Mark I Containment Program Mod & IE Bulletins 79-02 & 79-14

ML20150F727
Person / Time
Site:	Browns Ferry
Issue date:	06/20/1988
From:	Blake J, Robert Carrion, Chou R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20150F721	List: IR 05000259/1988012 ML20150F718
References
50-259-88-12, 50-260-88-12, 50-296-88-12, IEB-79-02, IEB-79-14, IEB-79-2, NUDOCS 8807190021
Download: ML20150F727 (11)

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SAC UNITED STATES

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, g'f op,#>g NUCLEAR REGULATORY COMMISSION 3 / REGION 11 j 101 MARIETTA STREET. * * ATLANTA, GEORGt A 30323

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RepoftNos.: 50-259/88-12, 50-260/88-12, and 50-296/88-12 Licensee: Tennessee Valley-Authority 6N 38A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Docket Nos.: 50-259, 50-260 and 50-296 License Nos.: DPR-33, DPR-52, and OPR-68 Facility Name: Browns Ferry 1, 2, and 3 Inspection Conducted: May 2-6, 1988 Inspectors: ht1[ C- 14 4 [~/1 -N R. C. C Date Signed

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he 6 - /t, - b 8 .C rio Date Signed Approved by: y fu f ' 8 . B1 ke, Thief 'D' ate Signed Ma ri s and Processes Section D is n of Reactor Safety SUMMARY Scope: This routine, announced inspection was in the areas of Mark I Containment Long Term Program Modification, IEB 79-02, and IEB 79-1 Results: No violations or deviations were identified, i

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REPORT DETAILS

l Persons Contacted Licensee Employees-J. Beason Principal Engineer

• R. V. Bair,d, Civil Engineer

• B. D. Burke,' Task Engineer

• 8. B. Caldwell, Task Engineer

• J. W. Davenport Operations J.Emens,AssociateElectric~ Engineer J. Foster,-QC-Inspector E. Gaines, Principal Engineer J. Gaines, QC-Inspector

• M. Hamnond, Supervisor of. QA Surveillance Walkdown

'*C. S. Hsieh,-Compliance Licensing Engineer S. M. Kane Regulatory Licensing Engineer

• J. D. Martin Assistant to Plant Manager J. Pawlik,PlantSystemEngineer

• J. Savage, Compliance Licensing Manager

• C. N. Simms, lead Civil Engineer-T. Temale, Nuclear Engineer J. G. Walker, Plant Manager

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Other licensee employees contacted included craftsmen, engineers mechanics, l

technicians, and office personne Other Organization Stone and Webster Engineering Corporation-G. Byrnes, QC Manager

• K. E. Conrad, Assistant QC Manager D. Hanley, Field Engineer W. Hurt, QC Inspector p NRC Region II

• K. P. Barr, Acting Assistant Director for Inspection Programs, TVA Project

• A. Johnson, Project Engineer, Browns Ferry NRC Resident Inspectors

• F. Christnot, Resident Inspector

• L. Paulk, Senior Resident Inspector

• Attended exit interview l

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2 Mark I containment Long Term Program Modification (25585, TI 2515/85)

(0 pen)TI2515/85, Unresolved Safety Issue A-7. This is the sixth inspec-tion on Mark I Containment Long Term Program (LTP) Modification. The previous inspectors did inspections on welding, pipe supports, and/or status reports, mspection Report No. 50-259,260,296/81-20 documented welding inspections on stiffener plates, ring girders, and vent header restraints of the Torus Modification; Inspection Resort No. 50-259, 260,296/85-26 reinspected seven pipe supports associated with torus modi'ications,- six on the RHR line and one on the Core Spray lin Inspection Report No. 50-259,260,296/85-30 reported a reins)ection of seven supports in Drywell and Torus Purge System associatec with the torus modification; Inspection Report No. 50-259,260,296/85-41 documented the status report which stated the licensee reinspected 564 pipe supports associated with torus modifications in Unit 3 and found 431 supports with discrepancies; and Inspection Report No. 50-259,260,296/87-07 reported a reinspection of eight supports of "Torus Attached External Pipings" with three discrepancie Background The Browns Ferry Units 1, 2, and 3 containment systems are one of the first generation General Electric (GE) Boiling Water Reactor (BWR) nuclear steam supply systems housed in a containment structure designated as the Mark I Containment System. The original design of the Mark I Containment System included pressure and temperature loads associated with a loss-of-Coolant Accident (LOCA), seismic loads, dead loads, jet-impingement loads, hydrostatic loads due to water in the suppression chamber, overload pressure test loads, and constructions loads. Due to additional hydrodynamic loads, which were discovered later resulting from the dynamic effects of drywell air and steam being rapidly forced into the suppression pool (torus)

during a postulated LOCA and from suppression pool response to Safety Relief Valve (SRV) operation generally associated with plant transient operating conditions, the NRC required licensees to have a detailed reevaluation of the Mark I containment System. The resolution of this issue was divided into a short-term program and a long-term progra The Short-Term Program (STP) provided a rapid assessment of the adequacy of the containment to maintain i.ts integrity and functional ca3 ability when subjected to the loads induced by a design-basis LOCA, and used NUREG-0408 as a guideline. The NRC had approved the Brown Ferry's STP. The long-term program was to main-tain a margin of safety when the MARK I containment structures and pipingsystemsaresubjectedtoadditionalhydrodynamicloadsandwas identified by NRC as Unresolved Safety Issue (USI) A-7, Mark I Containment Long Term Program which would use NUREG-0661 as the design criteri The licensee, based on detailed testing, analytical work and modifications completed by 1983, summarized and submitted the result to the NRC as a Plant Unique Analysis Report (PUAR) dated January 3,1984. The NRC reviewed the licensee's PUAR for the 2001 dynamic and structural load aspects against the design criter a, NUREG-0661 and approved the PUAR on May 6, 1985.

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This inspection and the subsequent inspections to come later are to verify that the licensee had modified the plant with appropriate procedures, design, analysis, calculations and in accordance with the licensee commitments stated in the PUA The ins discussions with the licensee's responsible engineers.pectors held The walkdown reinspection areas included -torus external and internal structure modifications, drywell to wetwell differential pressure . system, vacuum breaker, temperature monitoring system, and attached external piping systems. The structural modif< cations inside the torus and below the torus water line such as safety relief valve cuenchers (T-Quencher) and supports were also discusse Unit 2 :s first to prepare for restart after the three units were shut down for almost three years. Therefore, most of the walkdown reinspection was performed in Unit 2. To verify the licensee commitment and performance, the inspectors randomly selected the following .

restraints and structural components that had been QC final inspected to see if they complied with commitments and as-built drawings. The restraints and structures were reinspected with the assistance of the licensee's QC inspectors, engineers, and crafhe b. Torus Exterior Modifications A walkdown was conducted to examine the exterior "omfications made to the Unit 2 Torus as committed to in the PUAR. becifically, the following items were inspected: torus tiedowns, exwrnal ring girder reinforcement beams, cradle reinforcement plates, torus dynamic restraint snubber assemblies, and the torus shell reinforcement at each ECCS header torus penetratio These items were compared to those illustrated on the following engineering drawings:

Drawing Revision 48W1246-2 5 48W1248-1 17 48W1248-3 9 48N1253-1 5 48W1265-1 4 The outside (farthest from the drywell) torus tiedown assemblies of ring girders #11 and #13 as well as the inside (closest the drywell)

assembly of ring girder #13 were checked. In addition, the external ring girder reinforcement beams and the cradle reinforcement plate were checked at these locations. No discrepancies between the drawings and as-built condition of these items were identified. Bent plate 1\" x 12" and 1" web p' late for reinforcement beams and cradle flange scab plates 1 " x 6 conform to Figures 5-1 and 5-2 of the PUA The torus dynamic restraint snubber assembly and its associated wall-mounted plate at ring girder #13 were reviewed and found to conform to the engineering drawings and Figure 5-1 of the PUA . ...

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The torus shell reinforcement for ECCS header torus penetration No. X-2040 was checked. 5/8" bent plates were found to conform to

'the Drawing No. 48N1253-1 and paragraph No. 5.2.6 of the PUA Torus Interior Modification A walk-down of the Unit 2 torus interior was done to review modifi-cations resulting from commitments made in the PVA The following drawings were reviewed:

Drawing Revision 47W401-5 18-7 6-8 7-11 3-12 3 47W403-1 14-2 18 48N1218-4 13 48W1218-7 13-8 8-9 9 48N1218-10 8 48W1218-11 1-12 2 48N1240-1 6 48N1245-2 5-4 2-5 1 48N1247-1 6 48N1249-1 7 48N1250-1 6-2 4 48W1251-1 10 L -2 6

! -3 7 l -4 2 l 48W1257-1 8 l 48W1259-1 7 ! 48W1260-3 2 48N1261-1 9 2 6 48N1262-1 6 Because water was in the torus to approximately elevation 535"-0",

it was not possible to see the modifications made in the lower portion of the torus, including the T-Quenchers and their respective supports, the horizontal downcomer tie bar and its attachment details,

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the lower attachment details of the vent header restraints, the attachment details of the HPCI turbine exhaust pipe restraints, and the attachment details of the RHR pump test line restrain Although it was not possible to closely inspect (i.e., measure member dimensions welds, etc.) the modifications above the water level due totheirdIstance(and,therefore, inaccessibility)fromthewalkway, a visual accounting of the major components, including their configu-ration and general physical condition, was complete The main steam relief valve vent piping and associated supports and restraints were checked for conformance to Drawing Nos. 47W401-5,-7,-

-8,-11, and -12. In particular, the "stiffener boxes," where the main vent piping penetrates the vent header in groups of two or three, the attachments to the vent piping itself (including rigid restraints, clevises, etc.), and the ring girder attachments and end attachments of the restraints were reviewe The vent header reinforcement plate around the four center downcomers of the non-vent bays, as described in paragraph 6.11.3 of the PUAR, was reviewed against Drawing No. 48N1240-1 for drawing conformanc The diagonal bracing for the downcomer tie bars and their attachment to the downcomers v a the bent plate and over-sized pipe arrangement was checked for drawing conformance and found to be acceptabl The torus spray header supports, as described in paragraph 8.7.1 of the PVAR, were verified as conforming to the engineering drawing Nos. 48W1259-1 and -2, including attachments to the spray header and torus ring girder, plus associated stiffener and gusset plate The torus walkway and access platforms for the vacuum breakers and their associated supports, as described in paragraphs 9.1 and 9.2 and figures 9-1, 9-2, and 9-3 of the PUAR, were reviewed for drawing conformance against Drawing Nos. 48W1251-1, -2, -3, and -4, noting in particular the design features intended to mitigate effects of seismic and hydrodynamic events, including slotted holes, bolted connections, and physical separations (between the walkway, which is supported from the ring girder, and the vacuum breaker access platforms, which are susaended from the vent header). No discrepancies were identif'e d. Torus Attached External Piping Modifications Nine new/ modified external piping supports for Unit 2 were checked for drawing compliance. The following supports were reviewed:

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Support System Drawing Revision R-27 HPCI 478455-118 6 R-28 HPCI 478455-120 2 R-64 .HPCI 478455-121 1 I H-9 RHR 478452-705 2 H-10 RHR 478452-986 3 H-11 RHR 478452-463 4 R-92 RHR 478452-892 2 R-93 RHR 478452-962 3 R-96 RHR 478452-970 1 R-96 Rl!R 478452-971 0 With the exception of H-9, all supports met the acceptance criteri H-9 deviated slightly from the drawing". The attachment lugs (shown in detail A705) are specified to be 1/2 thick and were measured to be 3/8" thick. A review of the calculations determined that the 3/8" thick plate is adequate for the loading condition Pending the licensee actions to review and revise the calculations and drawing, this new open item is identified as IFI 50-260/88-12-0 . (0 pen) Pipe Support Base Plate Designs Using Concrete Expansion Anchor Bolts - IEB 79-02 (25528)

TVA aerformed anchor bolt pullout test and inspection for IE8 79-0 Repa< r work was done for the oversized bolt holes on base plates. A few modifications for anchor bolts were serformed which might be combined with the modification requirements for EEB 79-14. See Paragraph 4 for the additional informatio . (0 pen) Seismic Analysis for As-Built Safety-Related Piping Systams - IEB 79-14 (25529) Units 1 and 3 All three units were shut down almost three years dua to the safety concern The vast majority of site activity is currently concen-trated on Unit The licensee plans to resume the modification work and other activities in Units 1 and 3 after Unit 2 is restarted. All long term code requirements and compliances for Units 1 and 3 for IEB 79-02 and IE8 79-14 will be met before they are restarted, o Unit 2 A seismic technical issues meeting was held between TVA, Stone and 198 Webster,andNRC-0SPatNRC'sWhiteFlintOfficeonFebruary29}ng The purpose of this meeting was to reach a common understand of the Browns Ferry Nuclear Plant (BFN) seismic technical issues and direction of the program for the resolution of these issues. The programs will involve the modifications and calculations on Civil Structures which include torus integrity, 79-14/79-02 program, cable

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tray supports, conduit supports, HVAC, small bore piping, CRD piping, drywell steel platforms, penetrations, equipment qualification, et The 79-14/79-02 program is a part of the seismic design program. The 79-14/79-02 program will included approximately 30 systems, 240 stress problems and 4000 supports for Unit 2 and common area. TVA had completed 20 stress problems and 500 supports which were included ~

in torus attached The remaining 79-14 (including 79-02) piping and CR0 piping systems. program will include 220 supports. TVA requested the NRC ap3roval at a meeting for (a) 3 phase plan and schedule for implementation of 79-14/79-02 program, and (b) use of Sequoyah i,1terim operability criteria (1.2 Sy and Su for steel allowable and Factor of Safety = 2 for anchors) for pnase II modifications which will be completed before restart. All Cnit 2 restarthaseisIIIscheduled modications will meet the on December long term 1,198 Thecode NRCrequirements-is currently reviewing the proposal. TVA altio presented the current status and proposal for 79-14/79-02 program as shown below based on the 3 phase plan:

Phase 1 (Completed before April 1988)

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Completed walkdowns

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Developed data base of supports Assembled data packages

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Identified Approximate 600 discrepancies (3 Units)

510 Acceptable or Minor 90 Modifications

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Resolving audit findings Phase II (To be con:pleted by December 1,1988)

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Initiated verification walkdowns

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Initiated analyses and calculations (40% to be completed before restart)

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Continuing data base activities Phase III (Next outage from June 1,1990 to February 1,1991)

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Installing all modifications After TVA finished Phase I walkdown inspection for IEB 79-14 and IEB-79-02, the NRC's inspectors and TVA QA audit personnel frequently revealed the discrepancies between as-built drawings and as-built conditions and concluded that the Phase I walkdown inspection was inadequat TVA has hired Stone and Webster Engineering Corporation as its A/E firm to finish Phases II and III. The current status of Phase II is that Stone and Webster has completed its walkdown inspec-tion of 952 supports,11200 ft on piping, and 38 package . .. _ __ . _~

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(1) Activity Observation After the inspectors learned that TVA hired Stone and Webster Engineering Corporation to perform Phase II verification wa?k-downs for the IEB 79-14/79-02 program, the inspectors decidea to observe the performance of the Stone and Webster Walkdown Inspection Team during a detailed inspection of a piping syste A typical inspection team consists of one field engineer and one certified QC inspector. Each serves to verify the other person's Wor The inspectors randomly selected NI-201-5R and 6R from Isometric Drawing No. 47W400-200 for the Static, Thermo, Dynamic Analysis

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of Main Steam Drain Piping. The inspectors observed the inspection and records taken for support No. M0H-1A and the piping segment (3" 4 sch 160) from Support No. MDH-4 thru MGH-3 and M0H-1A to the connection of the 26"4 Main Steam Line D. The phase II Verification Walkdown Team measured and verified dimensions, pipe size, pipe schedule, elbow size, elbow schedule, support location, support identification, branch, reduced tee, etc., and recorded discrepancies for pipe. They meast. red member size, ipe wall thickness (when used as a support men.ber) with 0-Meter pocket sized ultrasonic equipment), connection weld size, rregular weld, weld length, plate size, general dimensions paintthickness,springcandetails,theattachedmemberdetalls, etc. , and recorded the discrepancies for Support No. MDH-1 Overall, the team members perforced the detail inspection per the walkdown inspection procedures. The inspectors raised questions such as gap, interference with other members, measure-ment tolerances, etc. , to evaluate their know%dge about the procedure's requirements. After observing th. ceam inspection, the inspectors questioned why the attached support member was not cross-referencad and why there was no mention about paint being chipped off of the spring can nor about rust on the bottom flange (plate) on support No. MDH-1A. The verification team members answered that the attached member was a miscellaneous Civil Structural membe Neither the Civil Structural member nor the chipped paint with rust were raquired to be recorded on the drawing, per the walkdown inspection procedures. Actually, the attached Civil Structural member is part of a tower which supports an approximately 30"4 pipe. The inspectors discussed the above two concerns of the cross reference and defects with the licensee responsible er.gineers and Stone and Webster managers (including QA). They agreed to review the procedures and set standards for these concern (2) Procedures Reviewed The inspectors reviewed the following procedures for adequac No major concerns were found except the above cross reference and defect recording problem ;. ..

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(i) WDP SWEC-003, SDSP-9.8, Piping Walkdown Procedure, TVA (ii) 8FEP PI 87-49, Pipe Support Verification Pro m n, TVA (iii) ' BFPP 8-8, Technical Procedure for 79-14/02'fi" and Pi)e Support Qualification, Task S012, St Weaster Engineering Corporatio (3) Audit Program for Phase II'Walkdown Inspection Stone and Webster did not have an audit program or procedure to verify the performance and accuracy of 79-14/79-02 Phase II walkdown inspections. IVA.does have activities and procedures for vendor performance verification. The licensee's responsible supervisor told the inspectors that TVA has two means to verify the . accuracy of the Stone and Webster's walkdown inspection First, the licensee QA engineers can observe the walkdown ins)ection activities performed by the Stone and Webster team mem)er Second, the ;icensee QA engineers can perform a reverification check on the piping or supports for ..tich the reinspection has been completed by the Stone and Wel ster Walk-down Team Member The licensee has performed about eleven surveillance observations on between 40 to 50 supports. Six to eight supports have been rechecked independently by the licensee QA inspectors. They only found two dimension discrepancies with 3-1/2" and 3" differences. The licensee plans to check 10% of the total walkdown reinspection pipings and su) ports. The licensee agreed with the inspector's request to recuce dramatically the surveillance observations and increase the independent recheck to assure the accuracy and performance of Stone and Webster walkdown team inspection The Procedure No. SDSP-3.3, Quality Assurance Surveillance Monitoring was received in the region office and is currently being reviewe (4) Walkdown Reinspection for IEB 79-14 Modifications As part of the IEB 79-14 review, two hangers were checked to assure the licensee performance on suppet modification These hangers are designed to support the Unit 1 control rod drive return line and are found on Drawings 4781600-50001, Re". O and 4781600-S0002, Rev. These two hangers were selected from a group on which all work had been completed, including QC in:pection. The field elk-down of these hangers determined that installation was correctly executed; the as-built configuratlon, including dimensions, piece marks, and welds satisfactorily met acceptance criteria. No violations or deviations were identified in this inspectio . Exit Interview

The inspection scope cod results were summarized on May 6,1988, with

those persons indicated in paragra.rh 1. The inspectors described the l areas ineected and discussed in detail the inspection findings.

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Dissenting comments were not received from the license The following new item was identified during this inspection:

Inspector Followup Item (IFI) 50-260/88-12-01, Si:'e Discrepancy at End ,

Attachment in Torus External Pipe Support. See paragraph 2(d).

The licensee did not identify as proprietary any of the material provided to or reviewed by the inspectors during this inspectio ,-

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