TXX-4650, Deficiency Rept SDAR-188 Re Width of as-built Seismic Gap Between All Major Plant Structures.Issue Being Pursued Under Comanche Peak Response Team Program Plan Item Iic

Deficiency Rept SDAR-188 Re Width of as-built Seismic Gap Between All Major Plant Structures.Issue Being Pursued Under Comanche Peak Response Team Program Plan Item Iic

ML20138P496
Person / Time
Site:	Comanche Peak
Issue date:	12/17/1985
From:	Counsil W TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	Johnson E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
SDAR-188, TXX-4650, NUDOCS 8512260138
Download: ML20138P496 (2)

Text

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. Log # TXX-4650 TEXAS UTILITIES GENERATING COMPANY File # 10110 NKYWA Y TOWER . 400 NORTH OLIVE STREET, L.B. 8 8 . DAILAN. TEX AS 78201 US70a'0EE'A December 17, 1985 h' g d) D W- g Mr. Eric H. Johnson, Acting Director ) R l 8 G85 ../

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Division of Reactor Safety and Projects "B U. S. Nuclear Regulatory Commission '

611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76012

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION DOCKET N05. 50-445 AND 50-446 SEISMIC GAP QA FILE: CP-85-27, SDAR-188

Dear Mr. Johnson:

In accordance with 10CFR50.55(e), we are submitting the enclosed written report of actions taken to correct a deficiency regarding the width of the as-built seismic gap between all major plant structures (Seismic Category I buildings to Seismic Category I buildings).

Supporting documentation is available at the CPSES site for your Inspector's review.

Very truly yours,

/ W Mr. W. G. Counsil JCH/grr Attachment c- NRC Region IV-(0 + 1 copy)

Director, Inspection & Enforcement (15 copies)

U. S. Nuclear Regulatory Commission .

Washington, D.C. 20555 8512260138 851217 PDR ADOCK 05000445 S PDR l

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, A DEVESION OF TEXA8 UTILITTES ELECTitlC COMPANY

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ATTACHMENT

SEISMIC GAP DESCRIPTION During recent construction and design adequacy programs, concrete debris

was identified in the separation gaps between the fuel and auxiliary buildings. Subsequent investigations have revealed that the actual seismic gaps in isolated areas between major plant structures are less

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than as specified in the design documents.

Evaluation of the as-built gap dimensions data indicates these con-ditions could result in a significant and possibly adverse increase in seismic Category I building response during a safe shutdown event (SSE) and alter the dynamic response characteristics of Category I structures.

4 SAFETY IMPLICATION In the event the conditions had remained undetected, the adequacy of the major plant structures and associated support systems could be impaired

, ' during a seismic event.

CORRECTIVE ACTION 1

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! Minimum acceptable gap widths have been reevaluated and established for all specified areas. Debris and minimum gap violations have been identified for disposition by removal of the debris and actual widening of the gap. Specific deviations will be evaluated on a case-by-case basis and incorporated into the design documents if acceptable. Further

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correction or removal activities will be implemented if required.

This issue is being pursued under the Comanche Peak Response Team Program Plan Item II.c.

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