ML20073E005

Provides Confirmation That Equipment Designed to Mitigate Effects of ATWS Installed,Per Unresolved Safety Issue A-9. Diverse Scram Sys Installed During Sixth Refueling Outage Completed on 900705

ML20073E005
Person / Time
Site:	Davis Besse
Issue date:	04/24/1991
From:	Shelton D CENTERIOR ENERGY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
REF-GTECI-A-09, REF-GTECI-SY, TASK-A-09, TASK-A-9, TASK-OR 1932, NUDOCS 9104300010
Download: ML20073E005 (2)

Text

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'% CENTERf0R ENERGY  :

Donned C. Shehon 300 A M son Avenue Vce Presdent Nuclear toledo, OH 436520001 l Davis Besse (419)249 2300 Docket Number 50-346 License Number NPF-3 Serial Number 1932 April 24, 1991 l United States Nuclear Regulatory Commission Document Control Desk Vashington, D. C. 20555 l

Subject:

Status of Anticipated Transients Vithout Scram Modifications

-(Unresolved Safety Issue A-9)

' Gt.1tlemeni On Aprl) 5, 1991, the Nuclear Regulatory Commission (NRC) staff requested that Toledo Edison (TE) provide a status on the implementation of requirements relating to Unresolved Safety Issue (USI) A-9, " Anticipated Transients Vithout Scram (ATVS)." 10 CFR 50.62, the ATVS Rule, provided specific requirements for the installation of equipment designed to mitigate the effects of an ATVS. The purpose.of this letter is to provide confirmation that these requirements have been met.

Section (c)(1) of 10 CFR 50.62 requires that each pressurized vater reactor have equipment to automatically initiate the Auxiliary Feedvater System and initiate a turbine trip under conditions indicative of an ATVS.- To meet

this requirement,!TE proposed to take credit for an existing system (i.e.,

Steam and Feedvater Rupture Control System).that would perform this function.- No plant modifications were necessary. This approach was

-approved by the NRC in a' letter dated September 29, 1989 (Log Number 3077).-

Section'(c)(2) of 10 CFR 50.62 requires the installation of a Diverse Scram System (DSS):that is independent from the existing Reactor Protection System. The DSS was installed at Davis-Besse Nuclear Power Station during-the sixth refueling outage, which was completed on' July _5, 1990.

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.- Docket-Nu est 50-346 License Number NPF-3 Serial Number 1932 Page 2 Should you have any questions regarding this matter, please contact Mr. R. V. Schrauder, Manager - Nuclear Licensing, at (419) 249-2366.- l l

l Very ly yours, l' ~%

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-cc P. H. Byron, DB-1 NRC Senior Resident Inspector A. B. Davis, Regional Administrator, NRC Region III J. R. Itall, NRC Senior Project Manager H. D. Lynch, NRC Senior Project Manager Utility Radiological Safety Board