ML19270F054

Final Deficiency Rept Re Difference Between Design Drawings & Actual Plant Configuration.Error Found in Drawing Certification Process,Where a Portion of Residual Heat Removal Sys Was Modified Bedore Certificate of Drawings

ML19270F054
Person / Time
Site:	Sequoyah
Issue date:	01/04/1979
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML19270F051	List: ML19270F050 ML19270F054
References
NUDOCS 7901250087
Download: ML19270F054 (2)

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ENCLOSURE SEQUOYAH NUCLEAR PLANT PLANT CONFIGURATION DIFFERENT FROM DRAWINGS OF RECORD NCR 2P, 3P FINAL REPORT Description of Deficiency Preoperational drawings of record are design drawings which have been certified as showing the actual system configuration at the time Construction transfers responsibility for the system to Power Production.

These drawings consequently show what equipment has been installed and tested by Construction. Nonconformance 2P describes an error in the TVA drawing certification process where a modification to a portion of the Residual Heat Removal System had been completed before certifica-tion of the preoperational drawings of record for those systems. This modification was inadvertently onitted from the drawings that were certified "as constructed." In nonconformance 3P, several systems were found where wiring was not as it was shown on the drawings of record.

Theae nonconformances are exampics of a problem which nay affect other plant systems. It may have permitted Construction to install or modify equipment on other systems without Power Production being aware of the situation during preoperational testing of that system.

Safety Implication Since these deficiencies indicate a Sequoyah generic problem, the exact implications cannot be completely determined. The deficiencies could permit drawings to be certified which do not reflect the exact plant configuration. Therefore, if test or operational procedures, maintenance schedules, etc., were written depending on information shown on the drawings of record, inadequate or incorrect procedures may result.

If this occurred on a safety-related system, it could be postulated that the safe operation of the system could be affected. Consequently, this could adversely affect plant safety.

Corrective Action To correct the specific deficiencies on the identified nonconforming systems, the drawings of record have been changed to reflect the actual configuration. To correct the generic aspects of this deficiency, the importance of drawings of record accurately reflecting actual construc-tion at the time of system transfer has been reemphasized to Construction and Power Production personnel. This was accomplished in Construction in the regular weekly training sessions involving all engineering personnel on October 2, 1978, and was covered more specifienlly in the electrical and coordination units on October 23, 1978. Also, at some time before transfer of a system, the configuration is " fixed" and no further work is done on 79012500 3

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1 that nyutem without strict controls. At that time, nteps are taken to

. . , ensure the system drawings of record represent the "as constructed" plant configuration. Procedures are also available to control any plant changes after this point and to ensure the design drawings and any required testing reflect these changes on a timely basis. An a further check, TVA procedurca require all systen drawings of record to refIect the "au constructed" configuration of thelr respective system before the issuance of the operating license of the plant. These procedures are being revised to emphanize the requirements for accurate "an conutructed" drawings.

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