ML20149D748

Final Deficiency Rept CP-88-22 Re Svc Water Discharge Pipe Missile Protection.Initially Reported on 880128.Design Basis Document DBD-CS-081, General Structural Design Criteria, Established to Incorporate Tornado Missile Barrier Criteria

ML20149D748
Person / Time
Site:	Comanche Peak
Issue date:	02/05/1988
From:	Beck J, Counsil W TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
CP-88-22, TXX-88186, NUDOCS 8802100001
Download: ML20149D748 (2)

Text

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M EE log # TXX-88186 File # 10110 r C 903.5 1UELECTRIC

" # IU""b"'S ('I wnuun c.co a February 5, 1988 Exerwive ske Prendent V. S. Nuclear Regulatory Commission Attn: Document Ccntrol Desk Washington, D.C. 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION DOCKET NOS. 50-445 AND 50-446 SERVICE WATER DISCHARGE PIPE MISSILE PROTECTION SDAR: CP-88-22 (FINAL REPORT)

Gentlemen:

On January 28, 1988, we verbally notified your Mr. H. S. Phillips of a deficiency involving service water discharge pipe missile protection. We are conservatively reporting this issue under the provisions of 10CFR50.55(e).

The required information follows.

DESCRIPTI0tj During CPSES design validation of the Service Water System (SWS), missile protection design requirements were identified for the Service Water System discharge structure. The Service Water System discharge piping terminates at the discharge structure wall and the pipe ends are sub;ect to damage by tornado generated missiles. Due to the complexity associated with positively demonstrating that a tornado generated missile could never functionally impair the service water discharge pipe and parts of the discharge struture, we have elected to provide missile protection for this piping and structure.

The cause of this deficiency is inadequate tornado missile barrier design criteria. This deficiency is limited to the original design activities involving tornado missile protection.

SAFETY IMPLICATIONS failure to adequately protect the Service Water System discharge piping from postulated tornado generated missiles could cause disruption of the Service Water System supply of cooling water to safety related components within the plant.

This issue represents a deficiency in final design as approved and released for construction such that the design does not conform to the criteria and bases stated in the safety analysis report.

[$g es02200001 anonos A PDR ADOCK 0500o445 \

s PDR 400 horth Obve Street LB81 Dallas. Texas 1901 1

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TXX-88186 February 5,1988 Page 2 of 2 "

CORRECTIVE ACTION  ;

Tornado missile protection is being provided for the exposed ends of the Service Water System discharge piping by installing a removable concrete slab over the Service Water System discharge structure.

To prevent recurrence of this deficiency, Design Basis Document 0B0-C5-081, "General Structural Desien Criteria" has been established to incorporate the tornado missile barrier design criteria.

Corrective actions for Units 1 and 2 will be completed by September 26, 1988. ,

Very truly yours, W. G. Counsil By: i Jgph W. Beck Vice President, Nuclear Engineering c-Mr. R. D. Martin, Region IV l Resident inspectors, CPSES (3) t l

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