ML023180495

Technical Specification Bases (Tsb) Change 3.8.3 Distribution System - Operating

ML023180495
Person / Time
Site:	Oconee
Issue date:	11/04/2002
From:	Rosalyn Jones Duke Power Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML023180495 (6)

Text

Duke R. A.JONES Power. Vice President A Duke Energy Company Duke Power 29672 / Oconee Nuclear Site 7800 Rochester Highway Seneca, SC 29672 864 885 3158 864 885 3564 fax November 4, 2002 U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Attention: Document Control Desk

Subject:

Oconee Nuclear Station Docket Numbers 50-269, 270, and 287 Technical Specification Bases (TSB) Change Please see attached revisions to Technical Specification Bases (TSB) 3.8.8 Distribution System - Operating, which was implemented on October 24, 2002. The change revises the description in the LCO Bases Section of the associated equipment in each of the three ES power settings. Unit 2 is being modified to add an MCC per string (2XS4, 2XS5, and 2XS6). The Table (items 3A, 3B, and 3C) in the LCO Bases is revised to specifically reference the new MCCs. Each of the new MCCs listed is modified by a parenthetical statement indicating that it is only required to be a part of the ES power string when supplying safety related loads. This was necessary since safety related loads will be added later and there was no reason to consider the ES power string inoperable if the MCC became inoperable prior to the MCC actually powering safety related loads. The addition of MCCs 2XS4, 2XS5, and 2XS6, is part of the 600V Capacity modification to add more safety-related power capacity to the plant.

Attachment 1 contains the new TSB page and Attachment 2 contains the markup version of the Bases page.

If any additional information is needed, please contact Larry E. Nicholson, at (864-885-3292).

Very t uly yours, R. CAJones, Vice President Oconee Nuclear Site www duke-energy.corn

U. S. Nuclear Regulatory Commission November 4, 2002 Page 2 cc: Mr. L. N. Olshan Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Mr. L. A. Reyes, Regional Administrator U. S. Nuclear Regulatory Commission - Region II Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, Georgia 30303 Mel Shannon Senior Resident Inspector Oconee Nuclear Station Virgil R. Autry, Director Division of Radioactive Waste Management Bureau of Land and Waste Management Department of Health & Environmental Control 2600 Bull Street Columbia, SC 29201 "DistributionSystems - Operating B 3.8.8 BASES (continued)

APPLICABLE The initial conditions of accidents and transient analyses in the UFSAR, SAFETY ANALYSES Chapter 6 (Ref. 1) and Chapter 15 (Ref. 2), assume ES systems are OPERABLE. The AC, DC, and AC vital electrical power distribution systems are designed to provide sufficient capacity, capability, redundancy, and reliability to ensure the availability of necessary power to ES systems so that the fuel, Reactor Coolant System, and containment design limits are not exceeded. These limits are discussed in more detail in the Bases for Section 3.2, Power Distribution Limits; Section 3.4, Reactor Coolant System (RCS); and Section 3.6, Containment Systems.

The OPERABILITY of the AC, DC, and AC vital electrical power distribution systems is consistent with the initial assumptions of the accident analyses and is based upon meeting the design basis of the unit. This includes maintaining power distribution systems OPERABLE during accident conditions in the event of:

a. An assumed loss of all offsite power or all onsite AC electrical power; and

b. A worst-case single failure.

The distribution systems satisfy Criterion 3 of the 10 CFR 50.36 (Ref. 4).

LCO The AC, DC, and AC vital electrical power distribution systems are required to be OPERABLE. To be considered OPERABLE the AC Distribution System must include two energized main feeder buses capable of being automatically powered by a Keowee Hydro Unit. Each main feeder bus is considered OPERABLE if it is energized and connected to at least two ES power strings. Each of the three ES power strings is required to be energized. The three ES power Strings consist of the following:

1A) Switchgear TC 11B) Switchgear TD 1C) Switchgear TE 2B) Load Center X9 2C) Load Center 2A) Load Center X8 Xl0 3A) 600V MCC XS1, 3B) 600V MCC XS2, 3C) 600V MCC XS3, XS4 (Unit 2 only and XS5 (Unit 2 and XS6 (Unit 2 when supplying only when only when safety related supplying supplying safety loads), and safety related related loads) 1, 2, 3XSF loads) 4A) 208V MCC XS1 4B) 208V MCC XS2 4C) 208V MCC XS3 and 1,2, 3XSF OCONEE UNITS 1, 2, & 3 B 3.8.8-2 BASES REVISION DATED 10/24/02 I Distribution Systems - Operating B 3.8.8 BASES (continued)

APPLICABLE The initial conditions of accidents and transient analyses in the UFSAR, SAFETY ANALYSES Chapter 6 (Ref. 1) and Chapter 15 (Ref. 2), assume ES systems are OPERABLE. The AC, DC, and AC vital electrical power distribution systems are designed to provide sufficient capacity, capability, redundancy, and reliability to ensure the availability of necessary power to ES systems so that the fuel, Reactor Coolant System, and containment design limits are not exceeded. These limits are discussed in more detail in the Bases for Section 3.2, Power Distribution Limits; Section 3.4, Reactor Coolant System (RCS); and Section 3.6, Containment Systems.

The OPERABILITY of the AC, DC, and AC vital electrical power distribution systems is consistent with the initial assumptions of the accident analyses and is based upon meeting the design basis of the unit. This includes maintaining power distribution systems OPERABLE during accident conditions in the event of:

a. An assumed loss of all offsite power or all onsite AC electrical power; and

b. A worst-case single failure.

The distribution systems satisfy Criterion 3 of the 10 CFR 50.36 (Ref. 4).

LCO The AC, DC, and AC vital electrical power distribution systems are required to be OPERABLE. To be considered OPERABLE the AC Distribution System must include two energized main feeder buses capable of being automatically powered by a Keowee Hydro Unit. Each main feeder bus is considered OPERABLE if it is energized and connected to at least two ES power strings. Each of the three ES power strings is required to be energized. The three ES power Strings consist of the following:

1A) Switchgear TC 1B) Switchgear TD 1C) Switchgear TE 2A) Load Center X8 2B) Load Center X9 2C) Load Center X10 3A) 600V MCC XS1 Xsq 0(uý.,ýkz and 1, 2,3XSF 0,IJ Wlt, 4A) 208V MCC XS1 and 1, 2, 3XSF (U.,, A2 C..d,* (%

OCONEE UNITS 1, 2, & 3 B 3.8.8-2 Amendment Nos. 300, 300, & 300