ML20092L626

Forwards Description of Methodology & Schedule for Verification of Each of 24 Identified Important Thermo-Lag Barrier Parameters,As Discussed in 950830 Meeting W/Nrc

ML20092L626
Person / Time
Site:	Oyster Creek
Issue date:	09/22/1995
From:	J. J. Barton GENERAL PUBLIC UTILITIES CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
C321-95-2277, GL-92-08, GL-92-8, NUDOCS 9509280053
Download: ML20092L626 (15)

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GPU Nuclear Corporation Nuclear  :::en: 388 Forked River, New Jersey 08731-0388 609 971-4000 Writer's Direct Dial Number:

September 22,1995 C321-95-2277 U. S. Nuclear Regulatory Commission Att: Document Control Desk Washington, DC 20555

Subject:

Oyster Creek Nuclear Generating Station (OCNGS)

Docket No. 50-219 Response to the Follow-Up to the Request for Additional Information Regarding Generic Letter (GL) 92-08 NRC letter dated August 22,1995 requested additional detailed information regarding methodology, plan and schedule for verifying important barrier parameters based on previous NRC guidance that some of the important parameters can only be verified by detailed examination. At the GPU Nuclear /NRC meeting on this issue, held August 30,1995, GPU Nuclear agreed to provide a more detailed description of the specific OCNGS QA Program requirements that support verification of important parameters, as well as to consider the performance of additional detailed examinations of a representative sample of in-plant configurations, where reasonable and appropriate. The attachment to this letter provides a detailed description of the methodology and schedule for verification of each of the twenty four (24) identified important barrier parameters, based on the issues discussed at the GPU Nuclear /NRC meeting held on August 30,1995.

It should be noted that the NRC letter dated August 22,1995 identified the stairwell enclosure as an installed Thermolag configuration at OCNGS. GPU Nuclear letter to NRC, dated September 16,1994, provided the results of the Appendix R safe shutdown reanalysis for this area, which concluded that the stairwell enclosure installation was not required to be b h h .-)

9509280053 950922 i PDR ADOCK 05000219 P PDR GPU Nuclear Corporation is a suosuuy of General Public Utilities Corporation

, l C321-95-2277 Page 2 a one-hour barrier. The stairwell enclosure installation was removed from the scope of the Generic Ixtter (GL) 92-08 evaluation program, and is no longer considered as an installed Thermolag configuration requiring a fire endurance rating.

Sincerely,

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g[ J. J. Barton Vice President and Director, Oyster Creek DJD/ pip Attachments c: Administrator, Region I Oyster Creek NRC Resident In.spector Oyster Creek NRC Project Manager A. Marion - NEI G. M. Holahan, Director, NRC Division of Systems Safety And Analysis 1

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. Attachment I OCNGS THERMOLAG BARRIER PARAMETER VERIFICATION METHODOLOGY The following provides a detailed description of the methodology to be utilized to verify each of the identified important Thermolag barrier parameters which are applicable to OCNGS.

The additional detailed examinations of representative installed configurations described 2

below will be performed by November 1,1995. The results of the examinations will be reflected in the OCNGS Thermolag evaluation report to be submitted by December 31,1995, as referenced in our previous submittals. The attached Table 1 provides a summary of parameter verification efforts as discussed in the August 30,1995 meeting.

1. Raceway Orientation (horizontal, vertical, radial bends)

Method of Verification: This parameter has been verified by documented visual examination during walkdowns which identified the horizontal, venical, or mdial bend orientation.

2. Conduit Method of Verification: This parameter has been verified by documented visual examination during walkdowns which identified that the barrier protected is conduit and the respective conduit size. Verification has also been performed through the review of design drawings. QA program records (OCNGS Quality Control Installation Inspection Checklist IN-044, Rev. O, Items 11 and 15) also verified the type of raceway and size per drawings and annotations attached to the Plant Inspection Report.

3. Junction Boxes and lateral Bends Method of Verification: This parameter has been verified by documented visual examination during walkdowns which identified the location and support mechanisms for each junction box and lateral bend, and by review of design drawings. QA program records (OCNGS Quality Control Installation Inspection Checklist IN-044, Rev. O, Items 11 and 15) also verified the type of raceway and size per drawings

. and annotations attached to the Plant Inspection Report.

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~ C321-95-2277 Attachment I, Page 2 4: Ladder-back Cable Trav with Sinnie Laver Cable Fill .

Method of Verification: None. This parameter is not applicable since OCNGS has not installed any Thermolag fire barriers on cable trays.

5. Cable Trav with T-Sectip_q Method'of Verification: None. This parameter is not applicable since OCNGS 4 has not installed any Thermolag fire barriers on cable  :

trays.

6. Raceway Material (Aluminum, steel)

Method of Verification: This parameter has been verified by review of raceway design and installation records which confirms that OCNGS installed steel raceway material.

7. Sgooort Protection. Thermal Shorts (Penetrating elements)

Method of Verification: This parameter has been verified by documented visual examination during walkdowns which identified that installed supports, attachments, and other penetrating elements are protected, and by review of design drawings.

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8. Air Droos Method of Verification: This parametar is verified by documented visual examination during walkdowns which identified the existence of air drop configurations, and by review of design drawings. QA program records (OCNGS Quality

Control Installation Inspection Checklist IN-044, Rev. O, Item 15) also verified the installation details. Two (2) installed air drop configurations located in fire

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C321-95-2277 1 Attachment I, Page 3 a

l zone TB-FZ-llD will be disassembled during installation l l

of upgrades since no test data is currently available to support establishment of a fire endurance rating. l Inspection during disassembly will further support the i validity of QA program installation requirements for air i i drops.

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9. Baseline Fire Barrier Panel Thickness i

Method of Verification: This parameter has been verified by review of QA l program records for source inspections, material receipt inspections, and installation inspections performed.

Individual Source Inspection Reports, Receipt inspection Checklists (Document No. R-6133-5076.1, Items 1 through 8) verified material thickness for preformed

! conduit and panel sections. OCNGS Quality Control

! Insta0so" Inspection Checklist IN-044, Rev. O, item 5 I

verified proper rating material minimum thicknesses i installed.

1 Destructive examination performed on a 3-hour,1-1/2 inch conduit barrier envelope has verified adequate material thickness for the preformed conduit sections and for the preformed panel sections which form a box around supports.

Additional detailed examinations of representative installed configurations will be performed to verify this

, parameter, per Attachment II.

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10. Preformed Conduit Panels Method of Verification: This parameter has been verified by documented visual examination during walkdowns which identified the existence of preformed conduit panels versus non-preformed material.

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i C321-95-2277. ,

- Attachment I, Page 4

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11. Panel Rib Orientation (Parallel or Perpendicular to the Raceway)

Method of Verifiggip11: This parameter only applies to configurations using board material. Detailed examinations of representative l installed configurations will be performed to verify this I parameter, per Attachment II.

12. Unsupoorted Spans Method of Verification: This parameter has been verified for conduit installations by visual examination which identified raceway suppon span distances. QA record review also suppons the i verif'ication of the parameter on the basis of GPU Nuclear Installation Procedure SP-9000-41-005, Rev. 4, Para. 8.1 requirements for maximum support spacing for conduits.

OCNGS Quality Control Installation Inspection Checklist IN-044, Rev. O, Item 8 verified banding supports and distances. Suppon spans for conduit sections is not a concern as proper band spacing and the conduit itself provide adequate suppon for preformed conduit barriers.

Verification of unsupponed Thermolag barrier spans for configurations using board material applies to box enclosures. Detailed examination of the ductwork fire barrier will be performed as described in Attachment II to verify this parameter.

As discussed in our meeting of August 30,1995, we have been unable to bound existing box enclosures such as penetration boxes to existing NEI tested configurations. Additional NEI testing is planned for box enclosures. The need for detailed examination on these configurations will be detennined once the details of construction for this testing are identified and pending results of the test.

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C32th5-2277 3-Attachment I, Page 5

13. Siress Skin Orientation (Inside or Outside)

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Method of Verification: This parameter has been verified by review of QA records of results of material and installation inspections performed (OCNGS Quality Control Installation ,

2 Inspection Checklist IN-044, Rev. O, Item 11).

Destructive examination performed on a 3-hour,1-1/2 inch conduit barrier envelope has verified the existence of stress skin on the inside and outside of preformed conduit sections and for preformed panel sections which form a box around supports.

' Additional detailed examinations of representative installed configurations will be performed to verify this parameter, per Attachment II.

14. Stress Skin Over Joints or No Stress Skin Over Joints i

, Method of Verification: This parameter has been verified by review of design i records which document that OCNGS did not install stress skin overjoints. Since OCNGS did not use this design feature, and since comparisons are made to test configurations without this feature, no additional verification of this parameter is required.

15. Stress Skin Ties or No Stress Skin Ties Method of Verification: This parameter has been verified by review of design records which document that OCNGS did not install stress skin ties. Since OCNGS did not use this design feature and since comparisons are made to test configurations without this feature, no additional verification of this parameter is required.

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Attachment I, Page 6

16. Dry-Fit. Post-Buttemd Joints or Pm-buttered Joints Method of Verification: This parameter has been verified by review of QA l program installation inspection (OCNGS Quality Control l Installation Inspection Checklist IN-044, Rev. O, Item 7 for pre-buttered joints, and Item 8 for post-fill and alignment verifications).

Destnictive examination performed on a 3-hour,1-1/2 ,

' inch conduit barrier envelope has verified acceptable pm-buttering and post-buttering of joints of prefonned -

conduit ' sections and for preformed panel sections which form a box around supports. Seven (7) joints were

examined.

Additional detailed examinations of representative installed configurations will be perfonned to verify this parameter, per Attachment II.

17. Joint Gao Width Method of Verification: This parameter was not an original design requirement and therefore was not verified by the QA program.

However, OCNGS installation requirements specified that preformed sections are to be butted together and l Installation Inspection checks for misalignment prior to pre-buttering would have minimized joint gap widths.

Detailed examinations of representative installed configurations will be perfonned to verify this parameter, per Attachment II.

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. ii C321-95-2277 -

Attachment I, Page 7 l 1

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' 18.- Butt Joints or Grooved and Scored Joints l J

1 Method of Verification: This parameter has been verified by documented visual examination during walkdowns which identified the existence of butt joints or grooved and scored joints. I Grooved and scored joints applies to prefabricated panels and preformed conduit sections on radial bends.

Grooving and scoring joints does not apply to straight sections of preformed conduit.

Detailed examinations of representative installed configurations will be performed tc verify this parameter, per Attachment II.

19. Steel Bands or Tie Wires Method of Verification: This parameter has been verified by documented visual examination during walkdowns, which identified the installation of steel bands or tie wires. OCNGS Quality Control Installation Inspection Checklist IN-044, Rev. O, Item 8 verified the installation of steel bands or wires.

20. Band / Wire Soacing Method of Verification: This parameter has been verified by documented visual examination during walkdowns. Verification is also provided by review of OCNGS Quality Control Installation Inspection Checklist IN-044, Rev. O, Item 8, which verified the allowable band / wire spacing.

Destructive examination performed on a 3-hour,1-1/2 inch conduit barrier envelope has verified 5 inch average band / wire spacing on preformed conduit sections and preformed panel sections which form a box around

. supports.

C321-95-2277

, Attachment I, Page 8

21. Hand / Wire Distance to Joints Method of Verification: This parameter is currently applicable to OCNGS and can be verified by visual examination. The reason it is applicable is because NEI tested configurations incorporated installation requirements to locate bands or tie wires within 2 inches of each joint. This was not a requirement for original installation of Thermolag barriers at OCNGS. Additional NEI testing will seek to demonstrate that the 2 inch requirement is unnecessary.

If this testing is unsuccessful it will be necessary to install additional bands at OCNGS to meet the 2 inch requirement as part of corrective action to restore opembility of raceway fire barriers at OCNGS.

22. No_Intenial Bands in Trays i

Method of Verification: None. This parameter is not applicable since OCNGS has not installed any Thermolag protected cable trays. l l

23. No Additional Trowel Material Over Sections and Joints or Additional Trowel Material Applied  !

Method of Verification: This parameter has been verified by review of design and installation records which confirms that, except for approved repair activities, the installation of additional trowel material over sections and joints was not a design requirement for OCNGS. Since OCNGS did not use this as a design feature and since comparisons are made to test configurations without this feature, no additional verification of this parameter is required.

24 No Edge Guards or Edge Guards l

Method of Verification: This parameter has been verified by documented visual examination during walkdowns which identified the installation of edge guards or no edge guards.

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TABLE 1 OCNGS .

SUMMARY

OF VERIFICATION FOR IMPORTANT BARRIER PARAMETERS VERIFIED BY ADDITIONAL DETAILED PARAMETER VERIFICATION REOUIRED EXAMINATION

1. Raceway Orientation Yes - Verified by visual examination. No (Horizontal, Vertical, Radial Bends)

2. Conduit Yes - Verified by visual examination, No review of design records, and QA records.

3. Junction Boxes and Lateral Bends Yes - Verified by visual examination, review of No design records, and QA records.

4. Ladder-back Cable Tray with Single Layer No - No trays protected by fire barriers. N/A Cable Fill

5. Cable Tray with T-Section No - No trays protected by fire barriers. N/A

6. Raceway Material (Aluminum / Steel) Yes - Verified by review of design and No installation records. All raceway constructed of steel.

7. Support Protection, Thermal Shorts Yes - Verified by visual examination and by No (Penetrating Elements) review of design drawings.

8. Air Drops Yes - Verified by visual examination, review Yes - when of design drawings, and by QA records. disassembled Expect to upgrade the only two minor installed configurations at Oyster Creek.

Will involve dismantling for upgrade.

9. Baseline Fire Barrier Panel'Illickness Yes - Verified by review of QA program Yes records.

10. Preformed Conduit Panels Yes - Verified by visual examination. No l

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TABLE 1 OCNGS ,

SUMMARY

OF VERIFICATION FOR IMPORTANT BARRIER PARAMETERS -

VERIFIED BY ADDITIONAL DETAILED PARAMETER VERIFICATION REOUIRED EXAhENATION l

11. Panel Rib Orientation Yes - To be established by detailed examination. Yes

12. Unsupported Spans Yes - Verified by visual examination and QA Yes program record review for raceway supports. Detailed examination to verify

unsupported Thermolag panel span on ductwork fire barriers will be performed.

For other box enclosures, need for detailed examination to be determined based upon future NEI testing.

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13. Stress Skin Orientation Yes - Verified by review of QA program Yes records review.

14. Stress Skin Over Joints or No Stress Skin Yes - Verified by review of design records. No I i Over Joints Oyster Creek did not apply this detail to original installation.

15. Stress Skin Ties or No Stress Skin Ties Yes - Verified by review of design records. No  ;

Oyster Creek did not apply this detail to original installation. '

16. Dry Fit, Post-buttered or Pre-buttered Joints Yes - Verified by review of QA program Yes records.

17. Joint Gap Width Yes - OCNGS did not apply this detail to original Yes  ;

installation. To be established by detailed examination.

18. Butt Joints or Grooved and Scored Joints Yes - Verified by visual examination. Yes ,

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TABLE 1 OCNGS ,

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SUMMARY

OF VERIFICATION FOR IMPORTANT BARRIER PARAMETERS VERIFIED BY ADDITIONAL DETAILED

. PARAMETER VERIFICATION REOUIRED EXAhDNATION

19. Steel Bands or Tie Wires Yes - Verified by visual examination and QA No program records review.

20. Band / Wire Spacing Yes - Verified by visual examination and QA No program records review.

21. Band Wire Distance to Joints Yes - Verified by visual examination. No

22. No Internal Bands on Tray No - No trays protected by fire barriers. N/A i

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23. No Additional Trowel Material Over Sections Yes - Verified by review of design and No and Joints or Additional Trowel Material installation records. Oyster Creek did not Applied apply this detail to original installation.

24. No Edge Guards or Edge Guards Yes - Verified by visual examination. No E

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i Attachment II OCNGS THERMOLAG DETAILED EXAMINATION PLAN i

I Introdudiqu '

A sample detailed examination program representative of the identified configurations will be performed to verify important parameters as detailed in Attachment I. The examination program demonstrates the accuracy of quality verification records for those parameters which can not be verified by visual examination.

Where verification is required and available by visual examination, GPU Nuclear has identified these parameters for each installed configuration. Demonstrating the accuracy of

. Quality Control records and investigating parameters which are important but not part of original installation records will further support reliance on records and examination results

to complete the list of data required to compare installed configurations with tested configurations using data from the NEI application guide. The number of configurations

included in the detailed examination program constitutes a representative sample of installed Thermolag fire barriers at OCNGS, 4

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SAMPLE SAMPLE PARAMETERS i CONFIGURATION POPULATION POINTS TO BE VERIFIED i l

A. Boxes (laterals I corner of I box l-3 way corner: 2 Baseline Fire Barrier 1 l

& LBDs,1-hour (3 panels) thickness Panel Thickness barriers only measurements on each

! installed) of 3 panels,2 Panel Rib Orientation 1

l thickness measurements on the Unsupported Spans 2 joints & i I

l measurement of joint Stress Skin Orientation gap widths, panel rib l orientation check Dry-Fit, Post-Buttered )

Joints or Pre-Buttered

' Joints Joint Gap Width Butt Joints or Grooved

& Scored Joints i

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SAMPLE SAMPLE PARAMETERS CONFIGURATION POPULATION POINTS TO BE VERIFIED j B.1-Hour Conduit I single conduit 1-4 way intersection: Baseline Fire Barrier i & Radial Bends butt joint of 4 2 thickness Panel Thickness preformed conduit measurements on each half sections of 4 preformed Stress Skin Orientation conduits,2 thickness measurements on each Dry-Fit, Post-Buttered of the 4 joints,2 Joints or Pre-Buttered circumference Joints readings each side of 4 joint. Joint Gap Width Butt Joints or Grooved

& Scored Joints C. 3-Hour Conduit I single conduit 1-4 way intersection: Baseline Fire Barrier

& Radial Bends buttjoint of 4 2 thickness Panel Thickness preformed conduit measurements on each half sections of 4 preformed Stress Skin Orientation conduits,2 thickness measurements on each Dry-Fit Post-Buttered

of the 4 joints,2 Joints or Pre-Buttered Joints circumference readings on each side of end joint, stress Joint Gap Width 4 skin check Butt Joints or Grooved i & Scored Joints i

D. HVAC Duct I representative 2 side panel Baseline Fire Barrier

, location on each of measurements,1 Panel Thickness the 3 accessible examination of a sides bottom panel: 2 Panet Rib Orientation thickness measurements on each Unsupported Spans

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of side panels,2 thickness Stress Skin Orientation measurements on panel bottom, & 2 Dry-Fit Post-Buttered joint gap width Joints or Pre-Buttered measurements, Panel Joints rib orientation check Joint Gap Width Butt Joints or Grooved

& Scored Joints