ML18017B077

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Interim Deficiency Rept Re Omission of Addl Reinforcing Steel in Unit 1 Containment Bldg Exterior Wall.Work & Technical Procedures Revised to Include Design Drawings for Exterior Wall.Corrective Action to Be Completed by 800630
ML18017B077
Person / Time
Site: Harris  Duke Energy icon.png
Issue date: 05/12/1980
From:
CAROLINA POWER & LIGHT CO.
To:
Shared Package
ML18017B076 List:
References
NUDOCS 8005200528
Download: ML18017B077 (4)


Text

CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT UNITS 1, 2, 3, 4 OMISSION OF ADDITIONAL REINFORCING STEEL IN UNIT //1 CONTAINMENT BUILDING EXTERIOR WALL ADJACENT TO THE CONSTRUCTION OPENING FOR THE EQUIPMENT HATCH INTERIM REPORT MAY 12, 1980 REPORTABLE UNDER 10CFR50.55(e)

PREPARED BY: CAROLINA POWER & LIGHT COMPANY

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INTRODUCTION Reinforcing steel bars are detailed on design drawings which identify bar type, size, and location. Numerous drawings are required for the contain-ment building exterior wall to provide construction adequate information for installation. Separate profile drawings were developed for both ver-tical and horizontal bars in each of ten rows around the circumference of the building. Bethlehem also provided fabrication and installation draw-ings for two plane bending required of bars around major penetrations.

Other design drawings were utilized for additional reinforcing steel around penetrations and construction openings.

DESCRIPTION On or about April 9, 1980, the construction inspector assigned solely to inspection of reinforcing steel in the containment exterior wall dis-covered additional vertical and horizontal bars omitted adjacent to the construction opening for the equipment hatch. Concrete had already been placed on the west side of the opening which should have partially embedded the bars. The bars were discovered as missing when the inspector was reviewing a drawing identifying reinforcing steel within the construc-tion opening. Prior to the inspector's observation, the inspector and craft personnel had assumed any additional reinforcing steel would have been within the construction joint perimeter based on normal construction practices, the large size of the opening, and the relative distance previously placed concrete was from the equipment hatch.

SAFETY IMPLICATIONS Reinforcing steel was omitted from the exterior wall. Engineering evalua-tion of the affected area determined modified reinforcing steel could be installed adjacent to the previously placed concrete with no loss of design integrity.

The condition of omission and corrective action recommended by the design engineer is documented in PW-C-1361.

The exterior wall would not have been completed without the discrepant condition of reinforcing steel being discovered at some check point prior to actual placement" of concrete within the construction opening. There-fore, the potential for a deficiency in construction/inspection functions resulting in a condition of safety significance did not exist.

CORRECTIVE ACTION Circumstances surrounding the omission of the, rebar in the containment building were thoroughly investigated, design rev'iew and modification to reinforcing steel has been completed, and acceptance by the quality control staff was received prior to continued concrete placement. NRC concurrence was also obtained. Craft work procedures and inspection technical procedures were revised to include an inventory control of design drawings for the exterior wall concrete placements to preclude recurrence.

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, u Audit of previous exterior wall concrete placements, drawing review of reinforcing steel in highly stressed/complex areas of Class I structures, review of other discipline similarities, and application of findings to the QA program are continuing. It is anticipated that completion of corrective action will be accomplished by June 30, 1980.

DETAILED REFERENCES

1. CP&L internal letter, M. A. McDuffie to T. H. Wyllie dated April 9, 1980.
2. CP&L internal letter, N. J. Chiangi to distribution dated April 10, 1980.

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3. NRC letter, James P. O'Reilly to J. A. Jones dated April 10, 1980.
4. Discrepancy Report DR-C-522 dated April 9, 1980.
5. Deficiency and Disposition Report, DDR No. 387 dated April 9, 1980.
6. Permanent Waiver PW-C-1361 approved April 12, 1980.
7. NRC letter, James P. O'Reilly to J. A. Jones dated April 15, 1980.
8. CP&L letter, J. A. Jones to James P. O'Reilly dated April 16, 1980.
9. CP&L letter, J. A. Jones to James P. O'Reilly dated April 18, 1980.
10. NRC letter, James P. O'Reilly to J. A. Jones dated April 22, 1980.

CP&L internal letter, M. A. McDuffie to R. M. Parsons dated April 22, 1980.

12. CP&L internal letter, R. M. Parsons to W. D. Goodman dated April 22, 1980.