ML073440022

Westinghouse Eagle - 21 Process Protection System

ML073440022
Person / Time
Site:	Watts Bar
Issue date:	12/05/2007
From:	Bajestani M Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML073440022 (3)

Text

Tennessee Valley Authority, Post Office Box 2000, Sprng City, Tennessee'37381-2000 December 5, 2007 U.S. Nuclear Regulatory Commission ATTN:

Document Control Desk Mail Stop:

OWFN P1-35 Washington, D.C.

20,555-0001 In the Matter of Tennessee Valley Authority

))

Docke-t No.

50-391 WESTINGHOUSE EAGLE-WATTS BAR NUCLEAR PLANT (WBN)

UNIT 2 -

21 PROCESS PROTECTION SYSTEM The purpose of this letter is to notify the NRC that consistent with WBN Unit 1, TVA intends to use the Westinghouse Eagle-21 process protection system on WBN Unit 2.

The Westinghouse Eagle-21 process protection system is currently installed on WBN Unit 1.

TVA chose the Westinghouse Eagle-21 process protection system for WBN Unit 2 based on fidelity with WBN Unit 1, familiarity with the system, its proven design and the reliability it has shown in service at both WBN and Sequoyah.

The WBN Unit 2 Westinghouse Eagle-21 process protection system will be constructed to the same specification and standards as the WBN Unit 1 Eagle-21 system.

WBN Unit 2 hardware will be identical or equivalent to WBN Unit 1.

WBN Unit 2 safety related firmware will be identical to the WBN Unit 1 firmware.

DO3c

U.S. Nuclear Regulatory Commission Page 2 December 5, 2007 The Eagle-21 system was approved by the NRC for WBN Unit 1 prior to initial power operation in References 1 and 2.

In Reference 2, the staff concluded that TVA provided adequate diversity and defense against postulated common-mode failures.

The Westinghouse safety system setpoint methodology was approved for WBN Units 1 and 2 in Reference 3.

TVA has made one design change to the WBN Unit 1 Eagle-21 system under 10 CFR 50.59 after initial licensing.

An. external unidirectional communications interface was installed between the Eagle-21 test subsystem and the plant process computer.

This non-safety-related change allows the process computer to acquire data from the Eagle-21 system.

This same modification will be performed for the WBN Unit 2 Eagle-21 system.

If you have any questions, please contact me at (423) 365-2351.

Sincerely, Masoud estani Watts Unit 2 Vice President

References:

1. NRC letter dated June 13,

1989, "Eagle-21 System for Watts Bar Nuclear Plant"

2. NUREG-0847 Supplement No.

13 - Safety Evaluation Report related to the operation of Watts Bar Nuclear Plant Units I and 2, April 1994

3. NUREG-0847 Supplement No.

15 - Safety Evaluation Report related to the operation of Watts Bar Nuclear Plant Units 1 and 2, June 1995

U.S. Nuclear Regulatory Commission Page 3 December 5, 2007 cc:

Lakshminarasimh Raghavan U.S. Nuclear Regulatory Commission MS 08H4A One White Flint North 11555 Rockville Pike Rockville, Maryland 20852-2738 Joseph Williams, Senior Project Manager (WBN Unit 2)

U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Rockville, Maryland 20852-2738 Loren R. Plisco, Deputy Regional Administrator for Construction U.

S. Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center, Suite 23T85 61 Forsyth Street, SW, Atlanta, Georgia 30303-8931 U.

S.

Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, Georgia 30303-8931 NRC Resident Inspector Unit 2 Watts Bar Nuclear Plant 1260 Nuclear Plant Road Spring City, Tennessee 37381