ML20147C263

Safety Evaluation Accepting Util Responses to Generic Ltr 83-28,Item 2.1 (Part 1) Re Equipment Classification of Reactor Trip Sys Components

ML20147C263
Person / Time
Site:	Davis Besse
Issue date:	01/12/1988
From:	NRC
To:
Shared Package
ML20147C252	List: ML20147C247 ML20147C263
References
GL-83-28, NUDOCS 8801190147
Download: ML20147C263 (3)

Text

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• • • • • SAFETY EVALUATION REPORT GENERIC LETTER 83-28, ITEM 2.1 (PART 1)

EQUIPMENTCLASSIFICATION(RTSCOMPONENTS)

DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 DOCKET NO. 50-346

_ INTRODUCTION AND

SUMMARY

On February 25, 1983, both of the scram circuit breakers at Unit 1 of the Salem Nuclear Power Plant failed to open upon an automatic reactor trip signal from the reactor protection system. This incident was terminated manually by the operator about 30 seconds after the initiation of the automatic trip signal. The failure of the circuit breakers was determined to be related to the sticking of the undervoltage trip attachment. Prior to this incident, on February 22, 1983, at Unit 1 of the Salem Nuclear Power Plant, an automatic trip signal was generated based on steam generator low-low level during plant start-up. In this case, the reactor was tripped manually by the operator almost coincidentally with the automatic trip.

Following these incidents, on February 28, 1983, the NRC Executive Director for Operations (EDO), directed the staff to investigate and report on the f

generic implications of these occurrences at Unit 1 of the Salem Nuclear Power Plant. The results of the staff's inquiry into the generic implications of l ]

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2 4- the Salem unit incidents are reported in NUREG-1000, "Generic Implications of the ATWS Events at the Salem Nuclear Power Plant." As a result of this investigation, the Commission (NRC) requested (by Generic Letter 83-28 dated July 8, 19831) all licensees of operating reactors, applicants for an operating license, and holders of construction permits to respond to generic issues raised by the analyses of these two ATWS events.

This report is an evaluation of the response submitted by the Toledo Edison Company, the licensee for the Davis-Besse Nuclear Power Station, Unit 1. for Item .1 (Part 1) of Generic Letter 83-28. The actual documents reviewed as part of this evaluation are listed in the references at the end of the report.

Item 2.1 (Part 1) requires the licensee to confirm that all Reactor Trip System components are identified, classified and treated as safety-related as indicated in the following statement:

Licensees and applicants shall confirm that all components whose functioning is required to trip the reactor are identified as safety-related on documents, procedures, and information handling systems used in the plant to control safety-related activities, including maintenance, work orders, and parts replacement.

EVALUATION The licensee for the Davis-Besse Nuclear Power Station, Unit 1, responded to the requirements of Item 2.1 (Part 1) with a submittal dated December 9, 19832, The licensee stated in this sutamittal that the equipment classification Q-list  :

has been developed to the component level for the reactor trip system.

< Quality assurance requirements are defined for the safety related structures, ,

! i I systems and components identified in the Q-list in plant documents such as engineering drawings, bills of material, design specification, contracts, purchase orders procedures and instructions.

s 3 f CONCLUSION

t-i Based on our review of these responses, we find the licensee's statements confirm that a program exists for identifying, classifying and treating components that are required for performance of the reactor trip function as I

safety related. This program meets the requirements of Item 2.1 (Part 1) of l

) the Generic Letter 83-28, and is therefore acceptable.

REFERENCES

1. NRC Letter, D. G. Eisenhut to all Licensees of Operating Reactors, Applicants for Operating License, and Holders of Construction Permitig f

1 "Required Actions Based on Generic Implications of Salem ATWS Events i (Generic Letter 83-28)," July 8, 1983.

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4 2. Letter, R. P. Crouse, Toledo Edison Co., to J. F. Stolz, NRC, 1

j December 9, 1983.  ;

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