ML20236U647

Forwards Safety Evaluation Re Assessment of Errors in Util Analysis for Small Break Loca,Per 860718 Request.Incorrect Values Used in Analysis Result in Incomplete Compliance W/ 10CFR50,App K.Performance Requirements of 10CFR50.46 Met

ML20236U647
Person / Time
Site:	Davis Besse
Issue date:	11/27/1987
From:	Crutchfield D Office of Nuclear Reactor Regulation
To:	Norelius C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20236U649	List: ML20236U647 ML20236U653
References
TAC-62086, NUDOCS 8712030258
Download: ML20236U647 (1)

Text

SO -3 YG November 27',1987) l.

l MEMORANDUM T0: Charles G. Norelius, Director DISTRIBUTION Division of Reactor Projects, Doctet4He/ PD31 Plant Region III .NRC & Local PDRs GHolahan RIngram l 'FROM: Dennis M. Crutchfield, Director- ADeAgazio EJordan Division of Reactor Projects - III, 0GC JPartlow IV, V & Special Projects ACRS'(10)

Office of Nuclear Reactor Regulation-

SUBJECT:

REVIEW OF TOLEDO EDISON COMPANY ASSESSMENT OF INPUT ERRORS DISCOVERED IN SMALL BREAK LOSS-OF-COOLANT ACCIDENT ANALYSIS TIA86-29FM(TAC 62086)

Your memorandum to G. Holahan dated July 18, 1986, requested NRR assistance to review the effects of certain non-conservative assumptions erroneously .

1 used by Toledo Edison in'its analyses for Small Break Loss-of-Coolant accidents.

The non-conservative assumptions ~related to the low pressure trip setpoint,.

steam generator water level, main feedwater flow coastdown, and using both steam generators for decay heat removal.

]

The NRR staff has reviewed analyses presented by Toledo Edison and other documentation available. Based on this review, the staff agrees that certain  !

of the values used in the SBLOCA analyses are' incorrect'resulting in incomplete compliance with 10 CFR 50, Appendix K but concludes that there is reasonable ,

assurance that the Davis-Besse ECCS satisfies 10 CFR 50.46' performance i requirements and, therefore, operation of the plant poses.no undue risk to public health and safety. The Safety Evaluation supporting this conclusion is ,

enclosed.

This completes our efforts on TIA 86-29 FM.

original sianed bv GMH for/

Dennis M. Crutchfield, Director I Division of Reactor Projects -'111 IV, V & Special Projects ,

Office of Nuclear Reactor Regulation  !

j CONTACT: Albert De Agazio, NRR 49-28186 '

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ADeAgazio ilio GHolahan DCrutchfield <

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