IR 05000324/1992040

Insp Repts 50-324/92-40 & 50-325/92-40 on 921102-06 & 16-20. No Violations or Deviations Noted.Major Areas Inspected: Miscellaneous Structural Steel Verification Program & Anchorage of safety-related Motor Control Ctrs

ML20126E453
Person / Time
Site:	Brunswick
Issue date:	12/15/1992
From:	Chou R, Lenahan J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20126E447	List: IR 05000324/1992040 ML20126E444
References
50-324-92-40, 50-325-92-40, NUDOCS 9212290148
Download: ML20126E453 (12)

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Report Nos.: 50-325/92-40 and 50 324/92J40 t Licensee: Carolina Power and Light Company P. O. Box 1551 Raleigh, NC 27602 Docket Nos.: 50-325 and 50-324 License Nos.: DPR-71 and DPR-62 Facility Name: Brunswick 1 and 2 Inspection Conducted: November 2-6 and November 16-20, 1992 Inspectors:

J. J. Lenaha f/ V

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/ IVkt-R. C. Chou- mber 16-20 only) Date Signed Approved by: -/ // v I N J. J. BlqKe/ Chie F .Date Signed Materiap ind Processes Section Engineering Branch Division of Reactor Safety SUMMARY Scope:

This special, announced inspection was conducted in .the areas of the miscellaneous structural steel-verification program, anchorage of safety-related motor control centers and electrical back panels, repairs to masonry block' walls'.and licensee action on previous. inspection finding .

Results:

In the areas inspected, violations or deviations were not identifie Strengths or weaknesses were not identified during this i_nspectio :

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9212290148 921215 PDR ADOCK 05000324 PDR

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REPORT DETAILS Persons Contacted Licensee Employees H. Beane, Manager, Quality Control (QC)

P. Brown, System Engineer

• • • S. Callis, Licensing Engineer

• • J. Brown,-Unit 2 Plant Manager

• • • T. Eason, QC Supervisor

• • • S. Floyd, Manager Regulatory Compliance

• R. Godley, Manager, NRC Compliance L. Grzeck, Project Engineer, Misc. Steel, NED

• R. Knott, Principal Engineer, Nuclear Engineer Department (NED)

• • • J. Leininger, Onsite Manager, NECD

• A. Lucas, Vice_-President, Engineering

• • R. Morgan, Site Manager, Brunswick

• R. Tripp, Civil Engineer, NED

• • • S. Vann, Misc. Steel Project Manager, NED Other licensee employees contacted during this inspection included engineers, technicians, and administrative personne Other Organizations R. Bizzak, Civil / Structural Engineer - TENERA T. Logan, Site Manager, Bechtel E. Thomas, Senior Civil Engineer, Bechtel ,

NRC Resident inspectors  !

• • • R.-Prevatte, Senior Resident Inspector

• P. Byron, Resident Inspector

• D. Nelson, Resident ~ Inspector

• Attended November 6 exit interview

• • Attended November 20 exit intetview

• • • Attended both exit' interviews Miscellaneous Steel Verification. Project - Units-I and 2-(37700)_

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The Miscellaneous Steel Verification Project (MSVP) was previously inspected during inspections documented in NRC_ Inspection Report numbers 50-325, 324/92-20, 92-23,_92-27, and 92-33.. Details of the MSVP are described in these reports. During the current inspection, the inspectors reviewed design calculations;- examined repairs to_. structural _

steel platforms?in the drywell; and reviewed results- of licensee QC walkdowns and Bechtel QA audits. Details of the inspection are summarized below:

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4 2 Review of Bechtel- Design Calculations-The basic goal of the MSVP is to identify any irregularities in installation of the miscellaneous steel, and to determine if the -

irregularities effect the structural integrity of the miscellaneous steel platforms. -The irregularities will be evaluated for startup (operability) in accordance with FSAR criteria, as supplemented by the licensee, in submittals to the NRC Office of Nuclear Reactor Regulation (NRR). The licensee's design criteria and the overall MSVP have been reviewed and accepted by NRR, as documented in a Safety Evaluation Report' dated October 8, 199 The inspectors reviewed the following Bechtel procedures which control evaluation of the irregularities and provide design criteria for the evaluations:

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EDPI-4.90.02, Revision 0, Miscellaneous Steel Verification-Progra MSVP C-001, Revision 1, Civil Design Criteria for Irregularity Evaluation for the Miscellaneous Steel Verification Progra Calculation ORXB-1000, Guidelines for Addressing Generic Irregularities for Reactor Building Miscellaneous Stee During.an inspection conducted September- 14-18, 1992, documented in Inspection Report numbers 50-325,324/92-27, errors were found -

in two of four calculations reviewed by the inspectors. -This was,

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identified to the licensee as an-example'of violation 324/92-27-02. Subsequent to the inspection, further review of other Bechtel-

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calculations by licensee engineers disclosed calculation error The errors involved failure to properly document assumptions or design methods, failure to properly document conclusions in the:

calculations, math errors, transposition errors, or failure to-adhere-to-design criteria. After these problems were'identifled, Bechtel revised their program for eva?uation of the. irregularities:

by adding-additional review ~ steps to-their design _ control. program.-

The design engineers also received training in the design control process, with emphasis on proper documentation of assumptions,.

references and conclusions in the calculation-package 'The inspectors examined the calculations-listed in the Table below. The types of irregularities evaluated by the calculations l are also listed in the Table. The calculations were reviewed for l~ completeness, accuracy, adherence to design criteria and L procedural requirements, and acceptability of calculation methods in accordance with American Institute of Steel Construction (AISC) -

code criteria and good engineering practices.

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TABLE Review of Calculations for Evaluation of Walkdown Irregularities-Item Calculation Re Walkdown (1) Types of (2) Review (3)

_ No N N Package No, Irreaularities Comments-

1. RB2-1008 0 2-RB-C-EL 96'-0" -Insufficiant thread (K-L/21R-22R) engagement-Loose bolts RB2-1009 0 2-RB-D-EL.34'-9" -Loose bolts (N P/23R 24R) RB2-1020 0 2-RB-B-EL.29'-0" -Loose bolts Thickness of (S-T/20R-21R) -Bolt size base plate on difference p. 10 of the-Insufficient calculation thread engagement should be-1" instead of c ll".

- RB2-1021 0 2-RB-C-EL.103'-8" -Loose bolts (K-L/22R-23R)

5, 2RB-1022 0 2-RB-A-EL.34'9" -Insufficient thread -

(M-N/18R-19R) engagement-

-Missing nut t-Missing member (cross-brace)- RB-1025 0 2-RB-A-EL.60'-1" -One line weld- at Torsion (M-N/19R-20R) one connection' was not- -

considered in-the qualifi-cation of wel Magnitude.of torsion was negligible, RB2-1026 0 2-RB-D-EL.78'-6" -Gap between clip-

.(P-S/21R-22R) angle and web-Loose bolts 8, 2RB2-1034 0 2-RB-A-EL.ll4'-Sj"-Loose bolts (L-M/20R-21R) - <

~ RB2-1089 0 2-RB-D-EL.40'-0" -A single line weld (S-T/23R-24R)

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1 RB2-1209 0 2-RB-D- EL . 4 ' - 4 '/, -Insufficient A moment (S-T/22R-24R) weld length ' induced by eccentricity was not considered in weld qualifi-catio Magnitude of moment wa negligibl tiotes:

(1) Walkdown package number indicates location of structural steel. E.G. 2-RB-C-El 96'-0" (K-L/21R-22R) covers structural steel located at elevation 96'-0" between column lines K to L, and 21R to 22 (2) Calculations are for evaluation of irregularities for restart identified during Phase I walkdowns, except for item number 9 which covers irregularities identified during the Phase II walkdown (3) Discrepancies identified under Review Comments did not affect conclusions of calculations regarding operability for restar Based on review of the above calculations, the inspectors concluded that the calculations were satisfactory. The discrepancies identified under review comment listed in the above table were minor and did not affect operability of the connections. However, the inspectors did express concern regarding the comments and the need for designers / checkers /

reviewers to pay attention to details, especially in evaluation of the more complex irregularities. The inspectors also noted the need for more detailed sketches in the calculations to clarify assumptions and justifications and provide basis for design methods. This comment had also been identified by licensee reviewers and will be addressed in calculations completed in the future. Additional design calculations will be reviewed during future inspection Examination of Repairs to Miscellaneous Structural Steel Deficiencies (irregularities) identified in the structural steel are being repaired under trooble tickets, (i.e., maintenance work orders,) or plant modifications. The trouble tickets address correction of irregularities which can be repaired using existing plant procedures and drawings. Plant modifications are issued to cover repairs not covered by existing drawings ard procedure The inspector reviewed 25 trouble tickets issued to tighten approximately 200 loose bolts and replace approximately 25 missing i

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nuts / bolts in the Unit 2 reactor building and drywell. The inspector also reviewed five trouble tickets issued to repair corrosion on connections in the Unit 2 drywell and reactor building. The inspector reviewed the drawings (sketches) listed below which were issued under Plant Modification 92 077. These sketches show details for reinforcement of welds on 55 shear plates in the Unit 2 drywel Sketches reviewed were as follows:

Numbers SK 92077-C-1000 through C-1002, SK 92077-C-1006, Sheets 1 through 11, SK 92077-C-1009, Sheets 1 through.4, and SK 92077-C-1010, Sheet I through 9. The original construction drawings specified partial penetration welds on these connections. When inspecting the welds the Bechtel walkdown personnel were unable to determine if the existing welds were actually partial penetration welds. It did not appear that the shear plates had been prepared with a 30" bevel as specified on the drawings prior to making the original weld. The existing welds appear to be small single sided fillet welds which were incapable of carrying the design load The inspector walked down the Elevation 17 platform in the Unit 2 drywell and examined several shear plates where the weld reinforcement was completed. The new welds examined were acceptable. Accessibility problems necessitated revisions to the plant modification sketches for some connection details. These revisions were approved by Bechtel design engineers and the weld reinforcements were accomplished in accordance with the revised design details. Additional connection repairs will be examined in future inspection Licensee Review of Walkdown Inspection Results Subsequent to the NRC inspections documented in Inspection Report numbers 50-325, 324/92-27, the licensee initiated a program to review and assess the accuracy of Bechtel's Phase II walkdown -

inspection results. This program included verification of the accuracy of randomly selected walkdown packages by licensee QC inspection personnel, and review and assessment of the finding of Bechtel QA audits and the Bechtel ten percent reverification program. The inspector reviewed the findings of the licensee QC inspectors. The QC personnel identified some additional deficiencies not noted by the Phase II walkdown personnel in the four packages they reviewed. Several concerned flame cut holes and lack of washers. A few concerned missing bolts and differences were noted in inspection of a few welds. The licensee has combined the QC inspection finding with the results of the Bechtel QA audits and reverification programs to trend the data and determine if what additional actions, if any, are required to improve the Phase II walkdown results. The inspector will examined this area in a future inspectio Violations or deviations were not identifie I - - - ----- _--_ _________ ________ __

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6 Recirculation System Piping Whip Restraints During the walkdown in the drywell to examine the structural steel wold repairs, the inspector noted inconsistencies with some of the whip-restraints for the recirculation discharge and suction piping. The inconsistencies involved loose wire rope restraint on a few restraints on Train B, while the wire ropes were " tight" on corresponding restraints on Train A. Some loose lock nuts were also identified. The inspector walked the recirculation piping down with licensee system engineers who indicated all the wire rope restraints should have been tight. The system engineers initiated trouble tickets'to-addres.s these potential problems. Review of the construction / installation drawings disclosed setting of the whip restraints was based on results of thermal expansion testing performed during hot functio'nal testing pe.rformed at the end of coastruction. The inspector will review this data in a future inspection and review actions to disposition the trouble tickets.-

This item will be tracked as Inspector Follow-Item 324/92-40-01,- .

Recirculation System Piping Whip Restraint Clearance Violations or deviations were not identifie . Repairs to Hasonry Block Walls Units 1 and 2 (37700)

The licensee has performed a detailed review of masonry block w W classified as non-safety related during the original IEB 80-11 (Masonry Wall Design) analysis. The licensee has also reviewed the design criteria and functional requirements for masonry walls. Based on the results of these reviews, the licensee identified deficiencies on 51 masonry walls in the diesel generator building, control building, and the reactor buildings which required modification to comply with the licensee's updated design criteria and functional (operability)

requirement Examples of the reasons for modifications to masonr block walls included change in design function; (specifically control room habitability which required reclassification of six control room masonry walls from non-safety related to safety-related,)-installation-of safety-related equipment on or in proximity to masonry walls originally classified as non-safety related; and tornado design-considerations. The inspector examined modifications completed on the masonry block walls listed below and verified that the modifications were completed in accordance with design requirements. The modification design details are shown on the sketched listed below. Walls examined were as follows:

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Control Building Elevation 49, Wall-10c, Drawing N SK-910ll-C-Il59, Sheets 1 thru 4

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Control Building Elevation 49, Wall IF, Drawing.N SK-91011-C-1040, Sheets 20 through 23

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Control Building Elevation 49, Wall 6A, South Face, Drawing N SK-910ll-C-1040, Sheets 25, 27, and 29.

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Diesel Generator Building Elevation 50, Walls llA, llB, Drawing No. SK-910ll-C-ll54, Sheet 1 through 7

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Diesel Generator Building Elevation 50, Walls lit and llD, Drawing No. SK-910ll-C-ll87, Sheets 1 through 7 The inspector concluded that the walls were constructed in accordance with the design drawing detail Violations or deviations were not identifie . Modifications Required for Tornado Design Considerations - Units 1 and 2 (37700)

The inspector reviewed design drawings issued for tornado venting modifications to masonry walls in the diesel generator building and reactor buildings. These modifications consists of installation of - ,

either rupture discs or fire dampers, in the walls. Drawing reviewed were as follows: Numbers SK-92069-C-1000-C-1002, SK 92069-C-1003, Sheets 1 through 3, SK 92069-C-1007, Sheets 1 through 3, for modification to diesel generator building walls, including the AFFF mechanical equipment room, and numbers SK-92069-C-1021, SK 92069-C-1022, Sheets 1 and 2, SK-92069-C-1023, and SK 92069-C-1024, Sheets-1 and 2, for installation of automatic dampers in one wall of the resin storage room in the Units 1 and 2 reactor building .

The inspector examined work in progress for the modifications in the diesel generator building north and south airlocks and AFFF mechanical equipment room. This work included cutting of openings in the masonry block walls and installation of support frames for the rupture discs or fire damper _

The inspector also examined the completed modification to wall 6H in the control buildin This modification consisted of installation of a 1/2 inch thick steel cover plate over an opening in an external wall on the a roof of the control building elevator machine room. The purpose of the modification was to shield internal walls in the control building from tornado wind pressure. Modification details are shown on drawing number SK-910ll-C-ll57, Sheets 1 and The modification was constructed in accordance with design drawing detail Violations or deviations were not identifie . Action on Previous Inspection Findings (92701, 92702) (Closed) Deviation (325, 324/92-14-06), Failure to Construct Structural Steel in Accordance with FSAR Commitments. The licensee's corrective actions for this deviation are stated in a letter to NRC dated August 7, 1992, Subject: Brunswick Steam Elactric Plant, Unit Nos. I and 2, Reply to Notice of Violation and Notice of Deviation. The licensee initiated the Miscellaneous Steel Verification Program (MSVP) to ensure compliance with design

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i criteria delineated in the FSAR. The MSVp is discussed in detail  !

in Paragraph 2 of this report. The MSVP has been approved by the l NRC Office of Nuclear Reactor Regulation (See Safety Evaluation l Report dated October 8, 1992) and has been inspected by Region 11 inspectors, (0 pen) Unresolved item (325, 324/92-14 04) Structural Steel i Drawings Do Not Reflect As Built Conditions. This problem concerned the fact that the structural steel drawings for site structures have not been updated to show as-built condition After completion of Phase 11 of the MSVP, the structural steel drawings will be revised to reflect existing as-built condition ,

Licensee engineers are currently reviewing drawing index files to '

locate various structural steel drawings for use by Bechtel in-completing the MSV It appears some drawing may have been lost or misplaced 20 years ago at the end of construction, in cases where the drawings can not be located, an as built drawing is prepared for the structural steel during the Phase II walkdow This steel is then analyzed during the Phase 11 evaluation portion -

of the MSVP and any deficiencies will be identified and corrected to meet FSAR criteria. The Phase 11 portion of the MSVP is-scheduled for completion in late 1993. This item will remain open pending review of the updated as-built drawings for structural-steel, after completion of the MSV , (0 pen) Inspector followup item (325, 324/92-14-01), Evaluate Attachments to Masonry Block Walls. The inspector reviewed CP&L

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procedure DG Ill.19, NED Design Guide for Verification of Drilled in Anchors in Masonry Walls. This design-guide was-written to verify the adequacy of drilled-in anchors which attach various equipment to masonry walls at Brunswick. The procedure specifies the inspection and evaluation methodology for various type of anchors, including self-drilling anchors, wedge anchors, stud anchors, toggle bolts, and powder-actuated fasteners. The inspection program consisted of walkdown . inspections of all 137 safety-related masonry walls to identify attachments supported by .

anchors to the walls, and identification. of the type of-anchor Through bolted installations were not included in the scope of this program, since through bolting with a backing plate provides positive anchorage to masonry walls. A total of 39 walls were identified which had attachments supported-by some type of ancho A testing program was then conducted to determine the load carrying capacity of various types of anchors. The inspector examined the results of the testing performed on powder-actuated- .

fasteners and self-drilling anchors installed in the masonry _

walls. The testing consisted of determining the pull-out loads-on these type of anchors. Self-drilling anchors installed in solid (grouted) cells of masonry walls were not included in the pull-out

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testing progra Inspection / testing ci %ese types of anchors '

were limited to verification that the cells had been grouted by-drilling pilot holes in the wall The capacity of toggle bolts, and self-drilled anchors installed in grouted cells was developed

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analytically. Anchor installation parameters and design values were developed based on the pull-out test results and analytical program. A confirmatory walkdown inspection was then conducted to identify anchors which did not meet installation criteria, e.g.,

fastener not snug tight, missing hardware, cracks in masonry block near or adjacent to the anchors, thread engagement, etc. Trouble tickets were initiated to correct problem identified during the confirmatory walkdow The results of testing and inspection program are summarized in a report titled, Final Project Report for Verification on Anchors in the Masonry Walls. The inspector raiewed a draf t copy of this repor Licensee engineers stated the report will be completed and issued in December 199 Pending review of the completed final report, and further review of the inspection and test data, Ifl 325, 324/92-14-01 will remain open, d. (Closed) Unresolved item 325, 324/92-33-02, Adequacy of Licensee's Corrective Actions to Resolve MCC Anchorage Problems. In early 1989, .icensee engineers discovered that a number of 1/2 inch diameter anchor bolts / nuts were missing from six Motor Control Centers (MCC) on elevation 20 of the Unit I reactor buildin lionconformance report (NCR) number A 89 015 was issued to evaluate and disposition this problem. The inspectors reviewed calculation number 1-01534A-128, Unit 1 Reactor Building Elevation 20 MCC Anchor Evaluation. The calculation results indicated that the MCC were operable with the missing nuts. However licensee engineers issued six trouble tickets to install the missing nuts / bolt The NCR was closed out based on the calculation results and the initiation of the trouble ticket Review of the trouble tickets during a previous inspection (See NRC Report Nos. 50 325, 324/92-23) disclosed that the trouble tickets had never been complete The inspectors questioned licensee engineers why anchorage for other MCCs were not inspected in 1989 when the anchorage problem was originally discovered, and why the trouble tickets were issued when the MCC were operabl These discussioni, disclosed that the trouble tickets were issued to upgrade the MCC anchorage to comply with construction's details shown on drawing number 9527-F-18061, Unit 1 Motor Control Center foundations. Licensee engineers responsible for the original resolution of NCR A-89-015 stated that other MCCs were not inspected at the time since the six MCCs with missing anchors were determined to be operable, and that inspection of a sample or all of the remaining MCCs and other floor mounted electrical equipment would be accomplished under the planned program for seismic verification of nuclear plant equipment required by NRC to close out Unresolved Safety Issue USI-A-4 The work specified on the trouble tickets was not required for the six MCC to meet operability requiremeni.s. Since the licensee, on their own initiative, decided to reopen the entire question regarding MCC anchorage during the current outage, and conducted detailed inspection of all 46 MCCs installed at the plant, the inspector has no further question regarding adequacy of the corrective actions taken in 1989. The licensee also initiated k

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inspections of other floor mounted equipment to determined if this equipment was adequately anchored. This investigation was performed by EQE Consultants, who determined that although some of this electrical equipment had anchorage deficiencies,.the

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equipment was operable under the A-46 criteria. EQE recommended modifications (enhancements) to eight cabinets to restore the design margin. This work for the enhancements is planned for <

completion in the futur !

Results of inspection of the 46 MCCs by licensee engineers was reviewed during inspection 92-33. This inspector questioned the status of enhancements and repairs specified in EER 92-026 During the current inspection, the inspectors examined the following records documenting completions of corective actions:-  ;

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Plant-Modification 91-041, Field Revision 035, drawing- 4 number SK-9104441-C-1064, for repairs to MCC 2XE, 2XF, 2XG, '

and 2XH. Work completed October 12, 1992

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Trouble ticket WR/J0-92-AUU41 to tighten loose bolts on MCC IXG. Work completed September 24, 1992 ,

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Trouble tickets WR/J0-92-AVUZ1 and ALTJ1 to tighten loose bolts on MCC 1XDB. Work completed on September 24, 199 The question regarding justification for considering the 1/4 inch diameter " shipping" bolts in calculation 1-01534A-128 will_be addressed under unresolved item 325, 324/92-18-01. -The inspectors have no further questions at-this time regarding adequacy of the licensee's corrective actions to resolve the MCC anchorage deficiencies, (0 pen) Unresolved item 325, 324/92 18 01 Welding Qualification of ,

Motor Control- Center Panel Anchorage.- This unresolved item was opened due to use of incorrect weld size by-licensee engineers in calculation number 521706 C-001. During the current inspectio l the inspectors reviewed calculation No. 52171-C-003, Cabinet Base Weld Evaluation, Revision 0._ The inspector-raised the following '

concerns regarding this calculation:

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-- Justification of the use of a four percent damping value for-Operating Base Earthquake (OBE) seismic acceleration-value Justification of the value of 1650 pounds for cabinet'

weights on page 6 of_the calculations

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Justification _ for using the corner of the cabinets as a pivot point to calculate tensile loads on-the cabinet anchorage .icensee engineers stated they would provide the information to justify these assumptions to the inspectors. The question-

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regarding justification of the use of the 1/4 inch diameter

" shipping" bolts in calculation 1-01534A-128 will also be addressed under this unresolved item. This item will remain open pending further review by NR . Exit interview The inspection scope and results were summarized on November 6 and November 20, with those persons indicated in paragraph 1. The inspectors described the areas inspected and discussed in detail the inspection results. Proprietary information is not contained in this report. Dissenting comments were not received from the license Inspector followup Item 324/92-40 01, Recirculation System Piping Whip-Restraint Clearance, e

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