ONS-2014-064, Technical Specification (TS) Bases Change

Technical Specification (TS) Bases Change

ML14142A281
Person / Time
Site:	Oconee
Issue date:	05/12/2014
From:	Batson S Duke Energy Carolinas, Duke Energy Corp
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
ONS-2014-064
Download: ML14142A281 (42)

Text

DUKE Scott L. Batson FMIDC~VVice President Oconee NuclearStation Duke Energy ONO1VP 17800 Rochester Hwy Seneca, SC 29672 o: 864.873.3274 ONS-2014-064 f 864.873.4208 Scott.Batson@duke-energy.com May 12, 2014 ATTN: Document Control Desk U.S, Nuclear Regulatory Commission 11555 Rockville Pike Rockville, Maryland 20852

Subject:

Duke Energy Carolinas, LLC Oconee Nuclear Station Docket Numbers 50-269, 50-270, and 50-287 Technical Specification (TS) Bases Change Please find attached a change to the Oconee Nuclear Station (ONS) TS Bases. This change was processed in accordance with the provisions of Technical Specification 5.5.15, "Technical Specifications (TS) Bases Control Program." TS Bases Change 2014-04 revises TS Bases 3.4.3, RCS Pressure and Temperature Limits, and 3.4.12, Low Temperature Overpressure Protection, to make necessary changes as a result of the 54 EFPY Pressure and Temperature limits approved by Amendments Nos. 384, 386, and 385.

Any questions regarding this information should be directed to Boyd Shingleton at (864) 873-4716.

Sincerely, Scott L. Batson Vice President Oconee Nuclear Station Attachment www.duke-energy.com

U. S. Nuclear Regulatory Commission May 12, 2014 Page 2 cc: Mr. Victor McCree, Regional Administrator U.S. Nuclear Regulatory Commission, Region II Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200 Atlanta, GA 30303-1257 Mr. James R. Hall, Senior Project Manager (ONS)

(By electronic mail only)

U. S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation 11555 Rockville Pike Mail Stop O-8B1 Rockville, MD 20852 Mr. Eddy Crowe Senior Resident Inspector Oconee Nuclear Station

U. S. Nuclear Regulatory Commission May 12, 2014 Page 3 bcc: w/o attachments Lara Nichols C. J. Wasik - ONS Jeff Robertson - MNS R. D. Hart - CNS Dan Westcott CR3 Lee Grzeck - BNP Dave Corlett - HNP Richard Hightower - RNP Julia Olivier - Fleet w/attachments Document Management ELL NSRB MR Coordinator (Ron Harris)

Licensing Working Group

luclearStation DUKE ENERGY Oconee Duke Energy 7800 Rochester Hwy Sen eca, SC 29672 May 12, 2014 Re: Oconee Nuclear Station Technical Specification Bases Change Please replace the corresponding pages in your copy of the Oconee Technical Specifications Bases Manual as follows:

REMOVE THESE PAGES INSERT THESE PAGES List of Effective Pages (LOEP) 1- 17 List of Effective Pages (LOEP) 1- 17 TS Bases Page B 3.4.3-1 thru 8 TS Bases Page B 3.4.3-1 thru 8 TS Bases Page B 3.4.12-1 thru 12 TS Bases Page B 3.4.12-1 thru 12 If you have any questions concerning the contents of this Technical Specification Bases update, contact Boyd Shingleton at (864) 873-4716.

's Wasik Regulatory Affairs Manager www.duke-energy.com

Attachment Oconee Nuclear Station Revised Technical Specification Bases Pages

OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE LOEP1 BASES REVISION 04/18/14 LOEP2 BASES REVISION 07/23/12 LOEP3 BASES REVISION 07/23/12 LOEP4 BASES REVISION 05/16/12 LOEP5 BASES REVISION 05/16/12 LOEP6 BASES REVISION 05/16/12 LOEP7 BASES REVISION 05/16/12 LOEP8 BASES REVISION 04/18/14 LOEP9 BASES REVISION 04/18/14 LOEP10 BASES REVISION 05/16/12 LOEP 11 BASES REVISION 11/13/12 LOEP12 BASES REVISION 08/08/12 LOEP13 BASES REVISION 01/16/14 LOEP14 BASES REVISION 01/16/14 LOEP15 BASES REVISION 05/16/12 LOEP16 BASES REVISION 07/25/13 LOEP 17 BASES REVISION 07/25/13 i BASES REVISION 06/03/11 ii 363/365/364 10/29/08 iii 355/357/356 4/2/07 iv 351/353/352 6/15/06 B 2.1.1-1 BASES REVISION 05/31/12 B 2.1.1-2 BASES REVISION 05/31/12 B 2.1.1-3 BASES REVISION 05/31/12 B 2.1.1-4 BASES REVISION 05/31/12 B 2.1.2-1 BASES REVISION 02/06/14 B 2.1.2-2 BASES REVISION 02/06/14 B 2.1.2-3 BASES REVISION 02/06/14 B 3.0-1 356/358/357 4/2/07 B 3.0-2 BASES REVISION 10/23/03 B 3.0-3 BASES REVISION 10/23/03 B 3.0-4 BASES REVISION 10/23/03 B 3.0-5 BASES REVISION 10/23/03 B 3.0-6 BASES REVISION 10/23/03 B 3.0-7 BASES REVISION 10/23/03 B 3.0-8 BASES REVISION 10/23/03 LOEPI

OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE B 3.0-9 BASES REVISION 10/23/03 B 3.0-10 BASES REVISION 10/23/03 B 3.0-11 BASES REVISION 10/23/03 B 3.0-12 BASES REVISION 10/23/03 B 3.0-13 BASES REVISION 10/20/11 B 3.0-14 BASES REVISION 10/23/03 B 3.0-15 BASES REVISION 10/23/03 B 3.1.1-1 BASES REVISION 05/16/12 B 3.1.1-2 BASES REVISION 05/16/12 B 3.1.1-3 BASES REVISION 05/16/12 B3.1.1-4 BASES REVISION 05/16/12 B 3.1.2-1 BASES REVISION 05/16/12 B 3.1.2-2 BASES REVISION 05/16/12 B 3.1.2-3 BASES REVISION 05/16/12 B 3.1.2-4 BASES REVISION 05/16/12 B 3.1.2-5 BASES REVISION 05/16/12 B 3.1.3-1 BASES REVISION 06/02/99 B 3.1.3-2 BASES REVISION 03/27/99 B 3.1.3-3 300/300/300 12/16/98 B 3.1.3-4 300/300/300 12/16/98 B 3.1.4-1 BASES REVISION 07/23/12 B 3.1.4-2 BASES REVISION 07/23/12 B 3.1.4-3 BASES REVISION 07/23/12 B 3.1.4-4 BASES REVISION 07/23/12 B 3.1.4-5 BASES REVISION 07/23/12 B 3.1.4-6 BASES REVISION 07/23/12 B 3.1.4-7 BASES REVISION 07/23/12 B 3.1.4-8 BASES REVISION 07/23/12 B 3.1.4-9 BASES REVISION 07/23/12 B 3.1.5-1 BASES REVISION 05/16/12 B 3.1.5-2 BASES REVISION 05/16/12 B 3.1.5-3 BASES REVISION 05/16/12 B 3.1.5-4 BASES REVISION 05/16/12 B 3.1.6-1 BASES REVISION 07/23/12 B 3.1.6-2 BASES REVISION 07/23/12 B 3.1.6-3 BASES REVISION 07/23/12 B 3.1.6-4 DELETE BASES REV. 07/23/12 LOEP2

OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE B 3.1.7-1 BASES REVISION 07/23/12 B 3.1.7-2 BASES REVISION 07/23/12 B 3.1.7-3 BASES REVISION 07/23/12 B 3.1.7-4 BASES REVISION 07/23/12 B 3.1.8-1 BASES REVISION 05/16/12 B 3.1.8-2 BASES REVISION 05/16/12 B 3.1.8-3 BASES REVISION 05/16/12 B 3.1.8-4 BASES REVISION 05/16/12 B 3.1.8-5 BASES REVISION 05/16/12 B 3.2.1-1 BASES REVISION 05/16/12 B 3.2.1-2 BASES REVISION 05/16/12 B 3.2.1-3 BASES REVISION 05/16/12 B 3.2.1-4 BASES REVISION 05/16/12 B 3.2.1-5 BASES REVISION 05/16/12 B 3.2.1-6 BASES REVISION 05/16/12 B 3.2.1-7 BASES REVISION 05/16/12 B 3.2.2-1 BASES REVISION 05/16/12 B 3.2.2-2 BASES REVISION 05/16/12 B 3.2.2-3 BASES REVISION 05/16/12 B 3.2.2-4 BASES REVISION 05/16/12 B 3.2.2-5 BASES REVISION 05/16/12 B 3.2.2-6 BASES REVISION 05/16/12 B 3.2.2-7 BASES REVISION 05/16/12 B 3.2.3-1 BASES REVISION 05/16/12 B 3.2.3-2 BASES REVISION 05/16/12 B 3.2.3-3 BASES REVISION 05/16/12 B 3.2.3-4 BASES REVISION 05/16/12 B 3.2.3-5 BASES REVISION 05/16/12 B 3.2.3-6 BASES REVISION 05/16/12 B 3.2.3-7 BASES REVISION 05/16/12 B 3.2.3-8 BASES REVISION 05/16/12 B 3.2.3-9 BASES REVISION 05/16/12 B 3.3.1-1 BASES REVISION 05/16/12 B 3.3.1-2 BASES REVISION 05/16/12 B 3.3.1-3 BASES REVISION 05/16/12 B 3.3.1-4 BASES REVISION 05/16/12 B 3.3.1-5 BASES REVISION 05/16/12 B 3.3.1-6 BASES REVISION 05/16/12 LOEP3

OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE B 3.3.1-7 BASES REVISION 05/16/12 B 3.3.1-8 BASES REVISION 05/16/12 B 3.3.1-9 BASES REVISION 05/16/12 B 3.3.1-10 BASES REVISION 05/16/12 B 3.3.1-11 BASES REVISION 05/16/12 B 3.3.1-12 BASES REVISION 05/16/12 B 3.3.1-13 BASES REVISION 05/16/12 B 3.3.1-14 BASES REVISION 05/16/12 B 3.3.1-15 BASES REVISION 05/16/12 B 3.3.1-16 BASES REVISION 05/16/12 B 3.3.1-17 BASES REVISION 05/16/12 B 3.3.1-18 BASES REVISION 05/16/12 B 3.3.1-19 BASES REVISION 05/16/12 B 3.3.1-20 BASES REVISION 05/16/12 B 3.3.1-21 BASES REVISION 05/16/12 B 3.3.1-22 BASES REVISION 05/16/12 B 3.3.1-23 BASES REVISION 05/16/12 B 3.3.1-24 BASES REVISION 05/16/12 B 3.3.1-25 BASES REVISION 05/16/12 B.3.3.1-26 BASES REVISION 05/16/12 B.3.3.1-27 BASES REVISION 05/16/12 B.3.3.1-28 BASES REVISION 05/16/12 B.3.3.1-29 BASES REVISION 05/16/12 B.3.3.1-30 BASES REVISION 05/16/12 B 3.3.2-1 BASES REVISION 12/14/04 B 3.3.2-2 BASES REVISION 12/14/04 B 3.3.2-3 BASES REVISION 12/14/04 B 3.3.3-1 BASES REVISION 05/16/12 B 3.3.3-2 BASES REVISION 05/16/12 B 3.3.3-3 BASES REVISION 05/16/12 B 3.3.3-4 BASES REVISION 05/16/12 B.3.3.3-5 BASES REVISION 05/16/12 B.3.3.3-6 BASES REVISION 05/16/12 B 3.3.4-1 BASES REVISION 05/16/12 B 3.3.4-2 BASES REVISION 05/16/12 B 3.3.4-3 BASES REVISION 05/16/12 B 3.3.4-4 BASES REVISION 05/16/12 B 3.3.5-1 BASES REVISION 05/16/12 B 3.3.5-2 BASES REVISION 05/16/12 B 3.3.5-3 BASES REVISION 05/16/12 B 3.3.5-4 BASES REVISION 05/16/12 LOEP4

OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE B 3.3.5-5 BASES REVISION 05/16/12 B 3.3.5-6 BASES REVISION 05/16/12 B 3.3.5-7 BASES REVISION 05/16/12 B 3.3.5-8 BASES REVISION 05/16/12 B 3.3.5-9 BASES REVISION 05/16/12 B 3.3.5-10 BASES REVISION 05/16/12 B 3.3.5-11 BASES REVISION 05/16/12 B 3.3.5-12 BASES REVISION 05/16/12 B 3.3.5-13 BASES REVISION 05/16/12 B 3.3.5-14 BASES REVISION 05/16/12 B 3.3.5-15 BASES REVISION 05/16/12 B 3.3.5-16 BASES REVISION 05/16/12 B 3.3.5-17 BASES REVISION 05/16/12 B 3.3.6-1 BASES REVISION 05/16/12 B 3.3.6-2 BASES REVISION 05/16/12 B 3.3.6-3 BASES REVISION 05/16/12 B 3.3.6-4 BASES REVISION 05/16/12 B 3.3.7-1 BASES REVISION 05/16/12 B 3.3.7-2 BASES REVISION 05/16/12 B 3.3.7-3 BASES REVISION 05/16/12 B 3.3.7-4 BASES REVISION 05/16/12 B 3.3.7-5 BASES REVISION 05/16/12 B 3.3.7-6 BASES REVISION 05/16/12 B 3.3.7-7 BASES REVISION 05/16/12 B 3.3.7-8 BASES REVISION 05/16/12 B 3.3.8-1 BASES REVISION 05/16/12 B 3.3.8-2 BASES REVISION 05/16/12 B 3.3.8-3 BASES REVISION 05/16/12 B 3.3.8-4 BASES REVISION 05/16/12 B 3.3.8-5 BASES REVISION 05/16/12 B 3.3.8-6 BASES REVISION 05/16/12 B 3.3.8-7 BASES REVISION 05/16/12 B 3.3.8-8 BASES REVISION 05/16/12 B 3.3.8-9 BASES REVISION 05/16/12 B 3.3.8-10 BASES REVISION 05/16/12 B 3.3.8-11 BASES REVISION 05/16/12 B 3.3.8-12 BASES REVISION 05/16/12 B 3.3.8-13 BASES REVISION 05/16/12 B 3.3.8-14 BASES REVISION 05/16/12 B 3.3.8-15 BASES REVISION 05/16/12 B 3.3.8-16 BASES REVISION 05/16/12 B 3.3.8-17 BASES REVISION 05/16/12 B 3.3.8-18 BASES REVISION 05/16/12 LOEP5

OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE B 3.3.8-19 BASES REVISION 05/16/12 B 3.3.8-20 Deleted 350/352/351 6/1/06 B 3.3.9-1 BASES REVISION 05/16/12 B 3.3.9-2 BASES REVISION 05/16/12 B 3.3.9-3 BASES REVISION 05/16/12 B 3.3.9-4 BASES REVISION 05/16/12 B 3.3.10-1 BASES REVISION 05/16/12 B 3.3.10-2 BASES REVISION 05/16/12 B 3.3.10-3 BASES REVISION 05/16/12 B 3.3.10-4 BASES REVISION 05/16/12 B 3.3.11-1 BASES REVISION 05/16/12 B 3.3.11-2 BASES REVISION 05/16/12 B 3.3.11-3 BASES REVISION 05/16/12 B 3.3.11-4 BASES REVISION 05/16/12 B 3.3.11-5 BASES REVISION 05/16/12 B 3.3.11-6 DELETE BASES REV 4/17/02 B 3.3.12-1 BASES REVISION 05/16/12 B 3.3.12-2 BASES REVISION 05/16/12 B 3.3.12-3 DELETE 320/320/320 9/26/01 B 3.3.13-1 BASES REVISION 05/16/12 B 3.3.13-2 BASES REVISION 05/16/12 B 3.3.13-3 BASES REVISION 05/16/12 B 3.3.13-4 BASES REVISION 05/16/12 B 3.3.14-1 BASES REVISION 05/16/12 B 3.3.14-2 BASES REVISION 05/16/12 B 3.3.14-3 BASES REVISION 05/16/12 B 3.3.14-4 BASES REVISION 05/16/12 B 3.3.15-1 BASES REVISION 05/16/12 B 3.3.15-2 BASES REVISION 05/16/12 B 3.3.15-3 BASES REVISION 05/16/12 B 3.3.16-1 BASES REVISION 05/16/12 B 3.3.16-2 BASES REVISION 05/16/12 B 3.3.16-3 BASES REVISION 05/16/12 B 3.3.16-4 BASES REVISION 05/16/12 B 3.3.17-1 BASES REVISION 05/16/12 B 3.3.17-2 BASES REVISION 05/16/12 B 3.3.17-3 BASES REVISION 05/16/12 B 3.3.18-1 BASES REVISION 05/16/12 B 3.3.18-2 BASES REVISION 05/16/12 B 3.3.18-3 BASES REVISION 05/16/12 B 3.3.18-4 BASES REVISION 05/16/12 LOEP6

OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE B 3.3.19-1 BASES REVISION 05/16/12 B 3.3.19-2 BASES REVISION 05/16/12 B 3.3.19-3 BASES REVISION 05/16/12 B 3.3.19-4 BASES REVISION 05/16/12 B 3.3.20-1 BASES REVISION 05/16/12 B 3.3.20-2 BASES REVISION 05/16/12 B 3.3.20-3 BASES REVISION 05/16/12 B 3.3.20-4 BASES REVISION 05/16/12 B 3.3.21-1 BASES REVISION 05/16/12 B 3.3.21-2 BASES REVISION 05/16/12 B 3.3.21-3 BASES REVISION 05/16/12 B 3.3.22-1 BASES REVISION 05/16/12 B 3.3.22-2 BASES REVISION 05/16/12 B 3.3.23-1 BASES REVISION 05/16/12 B 3.3.23-2 BASES REVISION 05/16/12 B 3.3.23-3 BASES REVISION 05/16/12 B 3.3.23-4 BASES REVISION 05/16/12 B 3.3.24-1 320/320/320 9/26/01 B 3.3.25-1 336/336/337 11/5/03 B 3.3.25-2 Delete,336/336/337 11/5/03 B 3.3.25-3 Delete,336/336/337 11/5/03 B 3.3.25-4 Delete,336/336/337 11/5/03 B 3.3.25-5 Delete,336/336/337 11/5/03 B 3.3.25-6 Delete,336/336/337 11/5/03 B 3.3.26-1 336/336/337 11/5/03 B 3.3.26-2 Delete,336/336/337 11/5/03 B 3.3.26-3 Delete,336/336/337 11/5/03 B 3.3.27-1 BASES REVISION 05/16/12 B 3.3.27-2 BASES REVISION 05/16/12 B 3.3.27-3 BASES REVISION 05/16/12 B 3.3.27-4 BASES REVISION 05/16/12 B 3.3.27-5 BASES REVISION 05/16/12 B 3.3.27-6 BASES REVISION 05/16/12 B 3.3.28-1 BASES REVISION 05/16/12 B 3.3.28-2 BASES REVISION 05/16/12 B 3.3.28-3 BASES REVISION 05/16/12 B 3.3.28-4 BASES REVISION 05/16/12 B 3.4.1-1 BASES REVISION 05/16/12 B 3.4.1-2 BASES REVISION 05/16/12 B 3.4.1-3 BASES REVISION 05/16/12 B 3.4.1-4 BASES REVISION 05/16/12 B 3.4.1-5 BASES REVISION 05/16/12 B 3.4.2-1 300/300/300 12/16/98 LOEP7

OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE B 3.4.2-2 300/300/300 12/16/98 B 3.4.3-1 BASES REVISION 04/18/14 B 3.4.3-2 BASES REVISION 04/18/14 B 3.4.3-3 BASES REVISION 04/18/14 B 3.4.3-4 BASES REVISION 04/18/14 B 3.4.3-5 BASES REVISION 04/18/14 B 3.4.3-6 BASES REVISION 04/18/14 B 3.4.3-7 BASES REVISION 04/18/14 B 3.4.3-8 BASES REVISION 04/18/14 B 3.4.4-1 BASES REVISION 05/16/12 B 3.4.4-2 BASES REVISION 05/16/12 B 3.4.4-3 BASES REVISION 05/16/12 B 3.4.4-4 BASES REVISION 05/16/12 B 3.4.5-1 BASES REVISION 05/16/12 B 3.4.5-2 BASES REVISION 05/16/12 B 3.4.5-3 BASES REVISION 05/16/12 B 3.4.5-4 BASES REVISION 05/16/12 B 3.4.6-1 BASES REVISION 05/16/12 B3.4.6-2 BASES REVISION 05/16/12 B 3.4.6-3 BASES REVISION 05/16/12 B 3.4.6-4 BASES REVISION 05/16/12 B 3.4.7-1 BASES REVISION 05/16/12 B 3.4.7-2 BASES REVISION 05/16/12 B 3.4.7-3 BASES REVISION 05/16/12 B 3.4.7-4 BASES REVISION 05/16/12 B 3.4.7-5 BASES REVISION 05/16/12 B 3.4.8-1 BASES REVISION 05/16/12 B 3.4.8-2 BASES REVISION 05/16/12 B 3.4.8-3 BASES REVISION 05/16/12 B 3.4.8-4 BASES REVISION 05/16/12 B 3.4.9-1 BASES REVISION 05/16/12 B 3.4.9-2 BASES REVISION 05/16/12 B 3.4.9-3 BASES REVISION 05/16/12 B 3.4.9-4 BASES REVISION 05/16/12 B 3.4.9-5 BASES REVISION 05/16/12 B 3.4.9-6 BASES REVISION 05/16/12 B 3.4.10-1 309/309/309 1/18/00 B 3.4.10-2 309/309/309 1/18/00 B 3.4.10-3 309/309/309 1/18/00 B 3.4.10-4 309/309/309 1/ 18/00 B 3.4.11-1 BASES REVISION 10/12/12 B 3.4.11-2 BASES REVISION 10/12/12 LOEP8

OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE B 3.4.11-3 BASES REVISION 10/12/12 B 3.4.11-4 BASES REVISION 10/12/12 B 3.4.11-5 DELETE BASES REV 10/12/12 B 3.4.12-1 BASES REVISION 04/18/14 B 3.4.12-2 BASES REVISION 04/18/14 B 3.4.12-3 BASES REVISION 04/18/14 B 3.4.12-4 BASES REVISION 04/18/14 B 3.4.12-5 BASES REVISION 04/18/14 B 3.4.12-6 BASES REVISION 04/18/14 B 3.4.12-7 BASES REVISION 04/18/14 B 3.4.12-8 BASES REVISION 04/18/14 B 3.4.12-9 BASES REVISION 04/18/14 B 3.4.12-10 BASES REVISION 04/18/14 B 3.4.12-11 BASES REVISION 04/18/14 B 3.4.12-12 BASES REVISION 04/18/14 B 3.4.13-1 BASES REVISION 05/16/12 B 3.4.13-2 BASES REVISION 05/16/12 B 3.4.13-3 BASES REVISION 05/16/12 B 3.4.13-4 BASES REVISION 05/16/12 B 3.4.13-5 BASES REVISION 05/16/12 B 3.4.13-6 BASES REVISION 05/16/12 B 3.4.14-1 BASES REVISION 05/16/12 B 3.4.14-2 BASES REVISION 05/16/12 B 3.4.14-3 BASES REVISION 05/16/12 B 3.4.14-4 BASES REVISION 05/16/12 B 3.4.14-5 BASES REVISION 05/16/12 B 3.4.14-6 BASES REVISION 05/16/12 B 3.4.15-1 BASES REVISION 05/16/12 B 3.4.15-2 BASES REVISION 05/16/12 B 3.4.15-3 BASES REVISION 05/16/12 B 3.4.15-4 BASES REVISION 05/16/12 B 3.4.15-5 BASES REVISION 05/16/12 B 3.4.16-1 355/357/356 4/2/07 B 3.4.16-2 355/357/356 4/2/07 B 3.4.16-3 355/357/356 4/2/07 B 3.4.16-4 355/357/356 4/2/07 B 3.4.16-5 355/357/356 4/2/07 B 3.4.16-6 355/357/356 4/2/07 B 3.4.16-7 355/357/356 4/2/07 B 3.5.1-1 BASES REVISION 05/16/12 B 3.5.1-2 BASES REVISION 05/16/12 B 3.5.1-3 BASES REVISION 05/16/12 B 3.5.1-4 BASES REVISION 05/16/12 B 3.5.1-5 BASES REVISION 05/16/12 LOEP9

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OCONEE NUCLEAR STATION TECHNICAL SPECIFICATIONS-BASES REVISED 04/18/14 LIST OF EFFECTIVE PAGES PAGE AMENDMENT BASES REVISION DATE B 3.8.5-1 BASES REVISION 05/16/12 B 3.8.5-2 BASES REVISION 05/16/12 B 3.8.5-3 BASES REVISION 05/16/12 B 3.8.5-4 BASES REVISION 05/16/12 B 3.8.5-5 BASES REVISION 05/16/12 B 3.8.5-6 BASES REVISION 05/16/12 B 3.8.6-1 BASES REVISION 05/16/12 B 3.8.6-2 BASES REVISION 05/16/12 B 3.8.6-3 BASES REVISION 05/16/12 B 3.8.6-4 BASES REVISION 05/16/12 B 3.8.7-1 BASES REVISION 05/16/12 B 3.8.7-2 BASES REVISION 05/16/12 B 3.8.7-3 BASES REVISION 05/16/12 B 3.8.8-1 BASES REVISION 05/16/12 B 3.8.8-2 BASES REVISION 05/16/12 B 3.8.8-3 BASES REVISION 05/16/12 B 3.8.8-4 BASES REVISION 05/16/12 B 3.8.8-5 BASES REVISION 05/16/12 B 3.8.8-6 BASES REVISION 05/16/12 B 3.8.8-7 BASES REVISION 05/16/12 B 3.8.8-8 BASES REVISION 05/16/12 B 3.8.8-9 BASES REVISION 05/16/12 B 3.8.9-1 BASES REVISION 05/16/12 B 3.8.9-2 BASES REVISION 05/16/12 B 3.8.9-3 BASES REVISION 05/16/12 B 3.8.9-4 BASES REVISION 05/16/12 B 3.9.1-1 BASES REVISION 05/16/12 B 3.9.1-2 BASES REVISION 05/16/12 B 3.9.1-3 BASES REVISION 05/16/12 LOEP15

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RCS P/T Limits B 3.4.3 B 3.4 REACTOR COOLANT SYSTEM (RCS)

B 3.4.3 RCS Pressure and Temperature (P/T) Limits BASES BACKGROUND All components of the RCS are designed to withstand effects of cyclic loads due to system pressure and temperature changes. These loads are introduced by startup (heatup) and shutdown (cooldown) operations, power transients, and reactor trips. This LCO limits the pressure and temperature changes during RCS heatup and cooldown, within the design assumptions and the stress limits for cyclic operation.

Figures 3.4.3-1 through 3.4.3-9 contain P/T limit curves for heatup, cooldown, and leak and hydrostatic (LH) testing. Tables 3.4.3-1 and 3.4.3-2 contain data for the maximum rate of change of reactor coolant temperature. The minimum temperature indicated in the P/T limit curves and tables of 60°F is the lowest unirradiated nil ductility reference temperature (RTNDT) of all materials in the reactor vessel. This temperature (60 0 F) is the minimum allowable reactor pressure vessel temperature if any head closure stud is not fully detensioned. There is no minimum allowable temperature limit for the reactor vessel if all of the studs are fully detensioned.

Figures 3.4.3-1, 3.4.3-2, 3.4.3-4, 3.4.3-5, 3.4.3-7 and 3.4.3-8 define an acceptable region for normal operation. The usual use of the curves is operational guidance during heatup or cooldown maneuvering, when pressure and temperature indications are monitored and compared to the applicable curve to determine that operation is within the allowable region.

The LCO establishes operating limits that provide a margin to brittle failure of the reactor vessel and piping of the reactor coolant pressure boundary (RCPB). The vessel is the component most subject to brittle failure, and the LCO limits apply mainly to the vessel. The limits do not apply to the pressurizer, which has different design characteristics and operating functions.

10 CFR 50, Appendix G (Ref. 1), requires the establishment of P/T limits for material fracture toughness requirements of the RCPB materials.

Reference 1 requires an adequate margin to brittle failure during normal operation, anticipated operational occurrences, and system hydrostatic tests. It mandates the use of the American Society of Mechanical Engineers (ASME), Boiler and Pressure Vessel Code,Section III, Appendix G (Ref. 2).

Linear elastic fracture mechanics (LEFM) methodology is used to determine the stresses and material toughness at locations within the RCPB. The LEFM methodology follows the guidance given by 10 CFR 50, Appendix G; ASME Code,Section III, Appendix G; and Regulatory Guide 1.99 (Ref. 3).

OCONEE UNITS 1, 2, & 3 B 3.4.3-1 BASES REVISION DATED 04/18/14 I

RCS P/T Limits B 3.4.3 BASES BACKGROUND Material toughness properties of the ferritic materials of the reactor (continued) vessel are determined in accordance with ASTM E 185 (Ref. 4), and additional reactor vessel requirements. These properties are then evaluated in accordance with Reference 2.

The actual shift in the nil ductility reference temperature (RTNDT) of the vessel material will be established periodically by evaluating the irradiated reactor vessel material specimens, in accordance with ASTM E 185 (Ref. 5) and Appendix H of 10 CFR 50 (Ref. 5). The operating P/T limit curves will be adjusted, as necessary, based on the evaluation findings and the recommendations of Reference 2.

The P/T limit curves are composite curves established by superimposing limits derived from stress analyses of those portions of the reactor vessel and head that are the most restrictive. At any specific pressure, temperature, and temperature rate of change, one location within the reactor vessel will dictate the most restrictive limit. Across the span of the P/T limit curves, different locations are more restrictive, and, thus, the curves are composites of the most restrictive regions.

The heatup curve represents a different set of restrictions than the cooldown curve because the directions of the thermal gradients through the vessel wall are reversed. The thermal gradient reversal alters the location of the tensile stress between the outer and inner walls.

The calculation to generate the LH testing curve uses different safety factors (per Ref. 2) than the heatup and cooldown curves.

The P/T limit curves and associated temperature rate of change limits are developed in conjunction with stress analyses for large numbers of operating cycles and provide conservative margins to nonductile failure.

Although created to provide limits for these specific normal operations, the curves also can be used to determine if an evaluation is necessary for an abnormal transient.

As stated in the tables associated with this LCO, reactor coolant (RC) temperature is cold leg temperature if one or more RC pumps are in operation; otherwise, it is the LPI cooler outlet temperature. An analysis examined the effects of initiating flow through a previously idle LPI train (i.e. either placing a train of LPI in operation or swapping from one train to the other) when none of the RC pumps are operating. The analysis assumed the initial temperature of the fluid entering the vessel to be the lowest expected temperature in an idle LPI cooler. As RC fluid is pumped through the system and returns to the reactor vessel, the temperature increases to a "stable" value. The duration of the temperature excursion is dependent on LPI flow and volume of the piping system. This analysis has determined that the brief temperature excursion caused by the fluid initially in the idle LPI train can be accommodated if, at the time the LPI header is put in service, the RCS pressure is less than 295 psig (Instrument Uncertainty Adjusted). This value is less limiting than the OCONEE UNITS 1, 2, & 3 B 3.4.3-2 BASES REVISION DATED 04/18/14 I

RCS P/T Limits B 3.4.3 BASES BACKGROUND LPI initiation pressure limit imposed by procedures to protect the LPI (continued) system from overpressure. The brief temperature excursion does not place the reactor vessel outside of the bounds of the stress analyses.

The criticality limit curve includes the Reference 1 requirement that it be 40°F above the heatup curve or the cooldown curve, and not less than the minimum permissible temperature for LH testing. However, the criticality curve is not operationally limiting; a more restrictive limit exists in LCO 3.4.2, "RCS Minimum Temperature for Criticality."

The consequence of violating the LCO limits is that the RCS has been operated under conditions that can result in brittle failure of the RCPB, possibly leading to a nonisolable leak or loss of coolant accident. In the event these limits are exceeded, an evaluation must be performed to determine the effect on the structural integrity of the RCPB components.

The ASME Code, Section Xl, Appendix E (Ref. 6) provides a recommended methodology for evaluating an operating event that causes an excursion outside the limits.

APPLICABLE The P/T limits are not derived from accident analyses. They are SAFETY ANALYSES prescribed during normal operation to avoid encountering pressure, temperature, and temperature rate of change conditions that might cause undetected flaws to propagate and cause nonductile failure of the RCPB, an unanalyzed condition. Reference 1 establishes the methodology for determining the P/T limits. Since the P/T limits are not derived from any accident analysis, there are no acceptance limits related to the P/T limits.

Rather, the P/T limits are acceptance limits themselves since they preclude operation in an unanalyzed condition.

RCS P/T limits satisfy Criterion 2 of 10 CFR 50.36 (Ref. 7).

LCO The three elements of this LCO are:

a. The limit curves for heatup and cooldown,

b. Limits on the rate of change of temperature, and

c. Allowable RC pump combinations.

The LCO is modified by three Notes. Note 1 states that for leak tests of the RCS and leak tests of connected systems where RCS pressure and temperature are controlling, the RCS may be pressurized to the limits of the specified figures. Note 2 states that for thermal steady state hydro tests required by ASME Section Xl RCS may be pressurized to the limits Specification 2.1.2 and the specified figures. The limits on the rate of change of reactor coolant temperature RCS P/T Limits are the same ones OCONEE UNITS 1, 2, & 3 B 3.4.3-3 BASES REVISION DATED 04/18/14 I

RCS P/T Limits B 3.4.3 BASES LCO used for normal heatup and cooldown operations. Note 3 states the RCS (continued) P/T limits are not applicable to the pressurizer.

The LCO limits apply to all components of the RCS, except the pressurizer. These limits define allowable operating regions and permit a large number of operating cycles while providing a wide margin to nonductile failure.

Table 3.4.3-1 includes temperature rate of change limits with allowable pump combinations for RCS heatup while Table 3.4.3-2 includes temperature rate of change limits with allowable pump combinations for RCS cooldown. The breakpoints between temperature rate of change limits in these two tables are selected to limit reactor vessel thermal gradients to acceptable limits. The breakpoint between allowable pump combinations was selected based on operational requirements and are used to determine the change of RCS pressure associated with the change in number of operating reactor coolant pumps.

The limits for the rate of change of temperature control the thermal gradient through the vessel wall and are used as inputs for calculating the heatup, cooldown, and LH P/T limit curves. Thus, the LCO for the rate of change of temperature restricts stresses caused by thermal gradients and also ensures the validity of the P/T limit curves.

The limits on allowable RC pump combinations controls the pressure differential between the vessel wall and the pressure measurement point and are used as inputs for calculating the heatup, cooldown and LH P/T limit curves. Thus, the LCO for the allowable RC pump combinations restricts the pressure at the vessel wall and ensures the validity of the P/T limit curves.

The LPI cooler outlet temperature during the brief period of stabilization does not need to be considered when determining heatup or cooldown rates or RCS P/T conditions when an LPI train is placed in operation with no operating RCPs. The period of stabilization is the time required to fully displace the stagnant fluid in the idle LPI train. The time required for stabilization is a function of LPI flow rate. Operating procedures control both placing a train of LPI in service and swapping trains of LPI to limit the duration of the temperature transient to a value that has been shown to be acceptable.

OCONEE UNITS 1, 2, & 3 B 3.4.3-4 BASES REVISION DATED 04/18/14 I

RCS P/T Limits B 3.4.3 BASES LCO Violating the LCO limits places the reactor vessel outside of the bounds of (continued) the stress analyses and can increase stresses in other RCPB components. The consequences depend on several factors, as follows:

a. The severity of the departure from the allowable operating P/T regime or the severity of the rate of change of temperature;

b. The length of time the limits were violated (longer violations allow the temperature gradient in the thick vessel walls to become more pronounced); and

c. The existences, sizes, and orientations of flaws in the vessel material.

APPLICABILITY The RCS P/T limits Specification provides a definition of acceptable operation for prevention of nonductile failure in accordance with 10 CFR 50, Appendix G (Ref. 1). Although the P/T limits were developed to provide guidance for operation during heatup or cooldown (MODES 3, 4, and 5) or LH testing, their applicability is at all times in keeping with the concern for nonductile failure. The limits do not apply to the pressurizer.

During MODES 1 and 2, other Technical Specifications provide limits for operation that can be more restrictive than or can supplement these P/T limits. LCO 3.4.1, "RCS Pressure, Temperature, and Flow Departure from Nucleate Boiling (DNB) Limits"; LCO 3.4.2, "RCS Minimum Temperature for Criticality"; and Safety Limit (SL) 2.1, "SLs," also provide operational restrictions for pressure and temperature and maximum pressure.

MODES 1 and 2 are above the temperature range of concern for nonductile failure, and stress analyses have been performed for normal maneuvering profiles, such as power ascension or descent.

ACTIONS A.1 and A.2 Operation outside the P/T limits during MODE 1, 2, 3, or 4 must be corrected so that the RCPB is returned to a condition that has been verified by stress analyses.

The 30 minute Completion Time reflects the urgency of restoring the parameters to within the analyzed range. Most violations will not be severe, and the activity can be accomplished in this time in a controlled manner.

Besides restoring operation to within limits, an evaluation is required to determine if RCS operation can continue. The evaluation must verify the RCPB integrity remains acceptable and must be completed before continuing operation. Several methods may be used, including comparison with pre-analyzed transients in the stress analyses, new analyses, or inspection of the components. The evaluation must be OCONEE UNITS 1, 2, & 3 B 3.4.3-5 BASES REVISION DATED 04/18/14 I

RCS P/T Limits B 3.4.3 BASES ACTIONS A.1 and A.2 (continued) completed, documented, and approved in accordance with established plant procedures and administrative controls.

ASME Code, Section Xl, Appendix E (Ref. 6) may be used to support the evaluation. However, its use is restricted to evaluation of the vessel beltline. The evaluation must extend to all components of the RCPB.

The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Completion Time is reasonable to accomplish the evaluation.

The evaluation for a mild violation is possible within this time, but more severe violations may require special, event specific stress analyses or inspections. A favorable evaluation must be completed before continuing to operate.

Condition A is modified by a Note requiring Required Action A.2 to be completed whenever the Condition is entered. The Note emphasizes the need to perform the evaluation of the effects of the excursion outside the allowable limits. Restoration alone per Required Action A.1 is insufficient because higher than analyzed stresses may have occurred and may have affected the RCPB integrity.

B.1 and B.2 If a Required Action and associated Completion Time of Condition A are not met, the unit must be brought to a lower MODE because: (a) the RCS remained in an unacceptable pressure and temperature region for an extended period of increased stress, or (b) a sufficiently severe event caused entry into an unacceptable region. Either possibility indicates a need for more careful examination of the event, best accomplished with the RCS at reduced pressure and temperature. With reduced pressure and temperature conditions, the possibility of propagation of undetected flaws is decreased.

If the required restoration activity cannot be accomplished within 30 minutes, Required Action B.1 and Required Action B.2 must be implemented to reduce pressure and temperature.

If the required evaluation for continued operation cannot be accomplished within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, or the results are indeterminate or unfavorable, action must proceed to reduce pressure and temperature as specified in Required Actions B.1 and B.2. A favorable evaluation must be completed and documented before returning to operating pressure and temperature conditions. However, if the favorable evaluation is accomplished while reducing pressure and temperature conditions, a return to power operation may be considered without completing Required Action B.2.

Pressure and temperature are reduced by bringing the unit to MODE 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and to MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion OCONEE UNITS 1, 2, & 3 B 3.4.3-6 BASES REVISION DATED 04/18/14 I

RCS P/T Limits B 3.4.3 BASES ACTIONS B.1 and B.2 (continued)

Times are reasonable, based on operating experience, to reach the required MODE from full power conditions in an orderly manner and without challenging unit systems.

C.1 and C.2 Actions must be initiated immediately to correct operation outside of the P/T limits at times other than MODE 1, 2, 3, or 4, so that the RCPB is returned to a condition that has been verified acceptable by stress analysis.

The immediate Completion Time reflects the urgency of initiating action to restore the parameters to within the analyzed range. Most violations will not be severe, and the activity can be accomplished within this time in a controlled manner.

In addition to restoring operation to within limits, an evaluation is required to determine if RCS operation can continue. The evaluation must verify that the RCPB integrity remains acceptable and must be completed prior to entry into MODE 4. Several methods may be used, including comparison with pre-analyzed transients in the stress analysis, or inspection of the components.

ASME Code, Section Xl, Appendix E (Ref. 6), may also be used to support the evaluation. However, its use is restricted to evaluation of the vessel beltline.

Condition C is modified by a Note requiring Required Action C.2 to be completed whenever the Condition is entered. The Note emphasizes the need to perform the evaluation of the effects of the excursion outside the allowable limits. Restoration alone, per Required Action C.1, is insufficient because higher than analyzed stresses may have occurred and may have affected RCPB integrity.

SURVEILLANCE SR 3.4.3.1 REQUIREMENTS Verification that operation is within limits is required when RCS pressure or temperature conditions are undergoing planned changes.

The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

Surveillance for heatup, cooldown, or LH testing may be discontinued when the definition given in the relevant plant procedure for ending the activity is satisfied.

OCONEE UNITS 1, 2, & 3 B 3.4.3-7 BASES REVISION DATED 04/18/14 I

RCS P/T Limits B 3.4.3 BASES SURVEILLANCE SR 3.4.3.1 (continued)

REQUIREMENTS This SR is modified by a Note that requires this SR to be performed only during system heatup, cooldown, and LH testing.

REFERENCES 1. 10 CFR 50, Appendix G.

2. ASME, Boiler and Pressure Vessel Code,Section III, Appendix G.

3. Regulatory Guide 1.99, Revision 2, May 1988.

4. ASTM E 185-82, July 1982.

5. 10 CFR 50, Appendix H.

6. ASME, Boiler and Pressure Vessel Code, Section Xl, Appendix E.

7. 10 CFR 50.36.

OCONEE UNITS 1, 2, & 3 B 3.4.3-8 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 B 3.4 REACTOR COOLANT SYSTEM (RCS)

B 3.4.12 Low Temperature Overpressure Protection (LTOP) System BASES BACKGROUND The LTOP System limits RCS pressure at low temperatures so the integrity of the reactor coolant pressure boundary (RCPB) is not compromised by violating the pressure and temperature (P/T) requirements of 10 CFR 50, Appendix G (Ref. 1). The reactor vessel is the limiting RCPB component for providing such protection. LCO 3.4.3, "RCS Pressure and Temperature (P/T) Limits," provides the allowable combinations for operational pressure and temperature during cooldown, shutdown, and heatup to keep from violating the Reference 1 limits.

The reactor vessel material is less ductile at reduced temperatures than at normal operating temperature. Also, as vessel neutron irradiation accumulates, the material becomes less resistant to pressure stress at low temperatures (Ref. 2). RCS pressure must be maintained low when temperature is low and may be increased only as temperature is increased.

Operational maneuvering during cooldown, heatup, or related anticipated transients must be controlled to not violate LCO 3.4.3. Exceeding these limits could lead to brittle fracture of the reactor vessel. LCO 3.4.3 presents requirements for administrative control of RCS pressure and temperature to prevent exceeding the P/T limits.

This LCO provides RCS overpressure protection in the applicable MODES by ensuring an adequate pressure relief capacity and a limit on coolant addition capability. The pressure relief capacity requires the power operated relief valve (PORV) lift setpoint to be reduced and administrative controls implemented which assure >_10 minutes available for operator action to mitigate an LTOP event. The administrative controls include limits on pressurizer level, limits on RCS pressure when RCS temperature is < 325 0 F, limits on RCS makeup flow, the number of available pressurizer heater banks, requirements for alarms and restrictions upon use of the High Pressure Nitrogen System.

The LTOP approach to protecting the vessel by limiting coolant addition capability requires controls upon RCS makeup flow, the number of available pressurizer heater banks, and requires deactivating HPI, and isolating the core flood tanks (CFTs).

Should one or more HPI pumps inject on an HPI actuation (HPI-ES) or a CFT discharge to the RCS, the pressurizer level and PORV may not prevent overpressurizing the RCS.

OCONEE UNITS 1, 2, & 3 B 3.4.12-1 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES BACKGROUND The administrative controls upon pressurizer level provides a (continued) compressible vapor space or cushion (either steam or nitrogen) that can accommodate a coolant insurge and prevent a rapid pressure increase, allowing the operator time to stop the increase. The PORV, with reduced lift setting, is the overpressure protection device that acts as backup to the operator in terminating an increasing pressure event.

With HPI-ES deactivated, the ability to provide RCS coolant addition is restricted. To balance the possible need for coolant addition, the LCO does not require the makeup system to be deactivated. Due to the lower pressures associated with the LTOP MODES and the expected decay heat levels, the makeup system can provide flow with the HPI pumps providing RCS makeup through the makeup control valve.

PORV Requirements As required for LTOP, the PORV is signaled to open if the RCS pressure approaches a limit set in the LTOP actuation circuit. The LTOP actuation circuit monitors RCS pressure and determines when an overpressure condition is approached. When the monitored pressure meets or exceeds the setting, the PORV is signaled to open. Maintaining the setpoint within the limits of the LCO ensures the Reference 1 limits will be met in any event analyzed for LTOP.

When a PORV is opened in an increasing pressure transient, the release of coolant causes the pressure increase to slow and reverse. As the PORV releases steam, the RCS pressure decreases until a reset pressure is reached and the valve is signaled to close. The pressure continues to decrease below the reset pressure as the valve closes.

Administrative Control Requirements Administrative controls are necessary to assure the operator has at least ten minutes available to mitigate the most limiting LTOP event. These administrative controls include the following:

1) Limits on RCS pressure based on RCS temperature;

2) Limits upon pressurizer level;

3) Limits upon makeup flow capability;

4) OPERABLE Alarms;

5) Controls upon use of the High Pressure Nitrogen System; and

6) Restricting the number of available pressurizer heater banks.

OCONEE UNITS 1, 2, & 3 B 3.4.12-2 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES BACKGROUND Administrative Control Requirements (continued)

Limiting RCS pressure based on RCS temperature provides a minimum margin to the RCS P/T limit. Restricting RCS makeup flow capability and pressurizer level and controls on the use of high pressure nitrogen limit the pressurization rate during an LTOP event. Restricting the number of available pressurizer heater banks limits the pressurization rate during an LTOP event. Alarms ensure early operator recognition of the occurrence of an LTOP event. The combination of minimum margin to the limit, limited pressurization rate and OPERABLE alarms ensure ten minutes are available for operator action to mitigate an LTOP event.

APPLICABLE Safety analyses (Ref. 3) demonstrate that the reactor vessel can be SAFETY ANALYSES adequately protected against overpressurization transients during shutdown. In MODES 1, 2, and in MODE 3 with RCS temperature exceeding 3250 F, the pressurizer safety valves will prevent RCS pressure from exceeding the Reference 1 limits. At nominally 325 0F and below, overpressure prevention falls to an OPERABLE PORV, a restricted coolant level in the pressurizer and other administrative controls.

The actual temperature at which the pressure in the P/T limit curve falls below the pressurizer safety valve setpoint increases as vessel material toughness decreases due to neutron embrittlement. Each time the P/T limit curves are revised, the LTOP System will be re-evaluated to ensure that its functional requirements can still be met with the PORV and pressurizer level/administrative controls method.

Transients that are capable of overpressurizing the RCS have been identified and evaluated. These transients relate to either mass input or heat input: actuating the HPI System, discharging the CFTs, energizing the pressurizer heaters, failing the makeup control valve open, losing decay heat removal, starting a reactor coolant pump (RCP) with a large temperature mismatch between the primary and secondary coolant systems, and adding nitrogen to the pressurizer. LTOP limits and restrictions take into account the presence of nitrogen and/or air in the RCS during LTOP conditions.

HPI actuation and CFT discharge are the transients that may result in exceeding P/T limits within < 10 minutes in which time no operator action is assumed to take place. Starting an RCP and adding nitrogen to the pressurizer are self limiting events. In the rest, operator action after that time precludes overpressurization. The analyses demonstrate that the time allowed for operator action is adequate, or the events are self limiting and do not exceed P/T limits.

OCONEE UNITS 1, 2, & 3 B 3.4.12-3 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES APPLICABLE The following controls are required during the LTOP MODES to ensure SAFETY ANALYSES that transients do not occur, which either of the LTOP overpressure (continued) protection means cannot handle:

a. Limiting RCS makeup flow capability;

b. Deactivating HPI-ES;

c. Immobilizing CFT discharge isolation valves in their closed positions; and

d. Limiting the number of available pressurizer heater banks.

The Reference 3 analyses demonstrate the PORV can maintain RCS pressure below limits when both makeup flow capability and the number of available pressurizer heater banks is restricted. Consequently, the administrative controls require makeup flow capability and the number of available pressurizer heater banks to be limited in the LTOP MODES.

Since the PORV cannot protect the reactor vessel for engineered safeguards actuation of one or more HPI pumps, or discharging the CFTs, the LCO also requires the HPI-ES actuation circuits be deactivated and the CFTs isolated. The isolated CFTs must have their discharge valves closed and the valve power breakers fixed in their open positions.

Fracture mechanics analyses established the temperature of LTOP Applicability at 3250 F. Above this temperature, the pressurizer safety valves provide the reactor vessel pressure protection. The vessel materials were assumed to have a neutron irradiation accumulation equal to 54 effective full power years (EFPYs) of operation for Units 1, 2, and 3.

This LCO will deactivate the HPI-ES actuation when the RCS temperature is _ 325 0 F.

Reference 3 contains the acceptance limits that satisfy the LTOP requirements. Any change to the RCS must be evaluated against these analyses to determine the impact of the change on the LTOP acceptance limits.

PORV Performance The fracture mechanics analyses show that the vessel is protected when the PORV is set to open at < 535 psig. The setpoint is derived by modeling the performance of the LTOP system for different LTOP events.

The PORV setpoint at or below the derived limit ensures the Reference 1 limits will be met.

OCONEE UNITS 1, 2, & 3 B 3.4.12-4 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES APPLICABLE The PORV setpoint is re-evaluated for compliance when the revised P/T SAFETY ANALYSES limits conflict with the LTOP analysis limits. The P/T limits are periodically (continued) modified as the reactor vessel material toughness decreases due to embrittlement induced by neutron irradiation. Revised P/T limits are determined using neutron fluence projections and the results of examinations of the reactor vessel material irradiation surveillance specimens. The Bases for LCO 3.4.3 discuss these examinations.

The PORV is considered an active component. Therefore, its failure represents the worst case LTOP single active failure.

Administrative Controls Performance Limiting RCS pressure when RCS temperature is < 325 0 F provides a minimum margin to the RCS P/T limit. Restricting RCS makeup flow capability, the number of available pressurizer heater banks, pressurizer level, and controls on the use of high pressure nitrogen limit the pressurization rate during an LTOP event. Alarms ensure early operator recognition of the occurrence of an incipient LTOP event. The combination of minimum margin to the limit, limited pressurization rate and OPERABLE alarms ensure ten minutes are available for operator action to mitigate an LTOP event.

RCS Vent Reguirements for Testing With the RCS depressurized, analyses show:

a. For HPI System testing, a vent of > 3.6 square inches is capable of mitigating the transient resulting from HPI-ES actuation testing in which three HPI pumps inject to the RCS through two injection flow paths.

b. For CFT Discharge Testing, a vent of >_201 square inches is capable of mitigating the transient resulting for discharge of both CFTs to the RCS.

The capacity of vents of these minimum sizes is sufficient to limit the RCS pressure to _ 400 psig, which is less than the maximum allowable pressure at minimum RCS temperature.

The RCS vent size will also be re-evaluated for compliance each time P/T limit curves are revised based on the results of the vessel material surveillance.

These vents are passive and not subject to active failure.

The LTOP System satisfies Criterion 2 and Criterion 3 of 10 CFR 50.36 (Ref. 4).

OCONEE UNITS 1, 2, & 3 B 3.4.12-5 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES LCO The LCO requires an LTOP System OPERABLE with a limited coolant input capability and a pressure relief capability. The LCO requires HPI to be deactivated and the CFTs to be isolated. For pressure relief, it requires the pressurizer coolant at or below a maximum level and the PORV OPERABLE with a lift setting < the LTOP limit.

The PORV is OPERABLE when its block valve is open, its lift setpoint is set at < 535 psig and testing has proven its ability to open at that setpoint, and power is available to the PORV and its control circuit.

An RCS vent path capable of mitigating the most limiting LTOP event (except for HPI-ES actuation or CFT discharge) has a minimum equivalent diameter of 1-3/32 inches, which is equal to the inner throat diameter of the PORV.

Implementation of the following administrative controls assure that _>10 minutes are available for operator action to mitigate an LTOP event:

1. RCS pressure:

< 375 psig when RCS temperature < 220°F

< 525 psig when RCS temperature > 220°F and < 325OF

2. Pressurizer level is maintained within the following limits:

a. RCS pressure is > 100 psig:

• <220 inches when RCS temperature < 3250 F

b. RCS pressure is < 100 psig:

< 310 inches when RCS temperature < 220 0F.

< 380 inches while filling or draining the RCS when RCS temperature < 160°F and no HPI pumps are running.

When the RCS pressure is < 100 psig, pressurizer level is normally maintained < 220 inches except for certain RCS evolutions. The specified pressurizer level limits provide assurance that at least 10 minutes is available for operator action during those evolutions. The temperature limits are based on operational limits for the evolutions and are used in the analyses to determine allowable pressurizer levels.

3. Makeup flow is restricted with the HP-1 20 (makeup control valve) travel stop set to < 98.0 gpm for all three units.

OCONEE UNITS 1, 2, & 3 B 3.4.12-6 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES LCO 4. Three audible pressurizer level alarms at _ 225 inches, _<260 (continued) inches, and _<315 inches from the temperature compensated pressurizer level indication.

5. Two audible RCS pressure alarms at 375 psig and 525 psig.

6. High pressure nitrogen system is administratively controlled to prevent inadvertent pressurization of the RCS.

7. Core Flood Tank(s) are isolated as required by the LCO by closing the appropriate isolation valve(s) (either CF-1 and/or CF-2), tagging open the valve breaker(s), and tagging the valve(s) in the closed position.

8. The HPI safety injection flowpaths must be deactivated.

a. Deactivating Train A of HPI is accomplished by either:

1) Shutting and deactivating valve HP-26 by tagging open the valve breaker and tagging the valve handwheel in the closed position, shutting valves HP-409 and HP-410 and tagging each valve switch in the closed position

2) Deactivating all HPI pumps aligned to HPI train A and tagging the pump breakers open.

b. Deactivating Train B of HPI is accomplished by either:

1) Shutting and deactivating valve HP-27 by tagging open the valve breaker and tagging the valve handwheel in the closed position, shutting valves HP-409 and HP-410 and tagging each valve switch in the closed position.

2) Deactivating all HPI pumps aligned to HPI train B and tagging the pump breakers open.

9. Pressurizer heater bank 3 or 4 must be deactivated.

Operational parameters identified in TS 3.4.12 and this TS Bases include allowances for instrument uncertainty.

APPLICABILITY This LCO is applicable in MODE 3 when any RCS cold leg temperature is

_<325 0 F, and in MODES 4, 5 and 6 when an RCS vent capable of mitigating the most limiting LTOP event is not open. The Applicability OCONEE UNITS 1, 2, & 3 B 3.4.12-7 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES APPLICABILITY temperature of 325 0 F is established by fracture mechanics analyses.

(continued) The pressurizer safety valves provide overpressure protection to meet LCO 3.4.3 P/T limits above 325 0 F. With the vessel head off, overpressurization is not possible. With an RCS vent capable of mitigating the most limiting LTOP event open, an LTOP event (including HPI-ES actuation or CFT discharge) is incapable of pressurizing the RCS above the RCS P/T limits.

A RCS vent _>3.6 square inches is capable of mitigating a HPI-ES actuation of three pumps through two flow paths to the RCS. A RCS vent

_ 201 square inches is capable of mitigating a discharge of both CFTs.

LCO 3.4.3 provides the operational P/T limits for all MODES. LCO 3.4.10, "Pressurizer Safety Valves," requires the pressurizer safety valves OPERABLE to provide overpressure protection during MODES 1, 2, and 3 above 325 0 F.

The Applicability is modified by two Notes. Note 1 states that CFT isolation is only required when the CFT pressure is more than or equal to the maximum RCS pressure for the existing RCS temperature, as allowed in LCO 3.4.3. This Note permits the CFT discharge valve surveillance performed only under these pressure and temperature conditions.

Note 2 permits the PORV to be inoperable when no HPI pumps are running and RCS pressure is < 100 psig. PORV operability is not required when RCS pressure is < 100 psig and HPI pumps are not operating since credible LTOP events progress relatively slowly, thus giving the operator ample time to respond.

ACTIONS A.1 With the HPI activated, immediate actions are required to deactivate HPI.

Emphasis is on immediate deactivation because inadvertent injection with one or more HPI pump OPERABLE is the event of greatest significance, since these events cause the greatest pressure increase in the shortest time.

The immediate Completion Times reflect the urgency of quickly proceeding with the Required Actions.

B.1, C.1, and C.2 An unisolated CFT requires isolation within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> only when the CFT pressure is at or more than the maximum RCS pressure for the existing temperature allowed in LCO 3.4.3.

OCONEE UNITS 1, 2, & 3 B 3.4.12-8 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES ACTIONS B.1. C.1, and C.2 (continued)

If isolation is needed and cannot be accomplished in 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, Required Action C.1 and Required Action C.2 provide two options, either of which must be performed in 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. By placing the unit in MODE 4 with the RCS temperature > 200 0 F, the CFT pressure of 650 psig cannot exceed the LTOP limits if both tanks are fully injected. Depressurizing the CFTs below the LTOP limit of 373 psig also prevents exceeding the LTOP limits in the same event.

The Completion Times are based on operating experience that these activities can be accomplished in these time periods and on engineering judgement indicating that a limiting LTOP event is not likely in the allowed times.

D.1, E.1, and E.2 With the PORV inoperable, overpressure relieving capability is lost, and restoration of the PORV within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> is required.

If restoration cannot be completed within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, either Required Action E.1 or Required Action E.2 must be performed. Required Action E.1 requires increasing RCS temperature within 23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br /> to exit the Applicability of the specification. With RCS temperature > 3250 F, the CFTs are not required to be isolated. Required Action E.2 requires the RCS be depressurized to less than 100 psig within 35 hours4.050926e-4 days <br />0.00972 hours <br />5.787037e-5 weeks <br />1.33175e-5 months <br />. With reactor pressure < 100 psig more time is available for operator action to mitigate an LTOP event.

These Completion Times also consider these activities can be accomplished in these time periods. A limiting LTOP event is not likely in these times.

F.1 and G.1 With Administrative Controls that assure >_10 minutes are available to mitigate the consequences of an event not implemented, the capability for operator action to mitigate an LTOP event may be lost. In this circumstance, compensatory measures must be established to monitor for initiation of an LTOP event. Establishing a dedicated operator within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to monitor for initiation of an LTOP event is sufficient to compensate for inoperability of makeup flow restrictions, having too many pressurizer heater banks available, inoperability of required alarms, or deviation from pressure, temperature or level limits. Establishing a dedicated operator is not sufficient to compensate for not deactivating HPI or isolating CFTs. If the Required Action and associated Completion Time of Condition F is not met, the RCS must be depressurized and an OCONEE UNITS 1, 2, & 3 B 3.4.12-9 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES ACTIONS F.1 and G.1 (continued)

RCS vent path capable of mitigating the most limiting LTOP event must be established within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. These Completion Times also consider that these activities can be accomplished in these time periods. A limiting LTOP event is not likely in these periods.

H.1 and H.2 With administrative controls which assure > 10 minutes are available to mitigate the consequences of an LTOP event not implemented and the PORV inoperable; or the LTOP System inoperable for any reason other than cited in Condition A through G, the system must be restored to OPERABLE status within one hour. When this is not possible, Required Action H.2 requires the RCS depressurized and vented within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

One or more vents may be used. A vent path capable of mitigating the most limiting LTOP event is specified. Because makeup may be required, the vent size accommodates inadvertent full makeup system operation.

Such a vent keeps the pressure from full flow of the makeup pump(s) with a wide open makeup control valve within the LCO limit.

The Completion Time is based on operating experience that these activity can be accomplished in this time period and on engineering judgement indicating that a limiting LTOP transient is not likely in this time.

SURVEILLANCE SR 3.4.12.1 and SR 3.4.12.2 REQUIREMENTS Verifications must be performed that HPI is deactivated, and the CFTs are isolated. These Surveillances ensure the minimum coolant input capability will not create an RCS overpressure condition to challenge the LTOP System. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.4.12.3 Verification that the pressurizer level is less than the volume necessary to assure > 10 minutes are available for operator action to mitigate an LTOP event by observing control room or other indications ensures a cushion of sufficient size is available to reduce the rate of pressure increase from potential transients.

OCONEE UNITS 1, 2, & 3 B 3.4.12-10 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES SURVEILLANCE SR 3.4.12.3 (continued)

REQUIREMENTS The 30 minute Surveillance Frequency during heatup and cooldown must be performed for the LCO Applicability period when temperature changes can cause pressurizer level variations. This Frequency may be discontinued when the ends of these conditions are satisfied, as defined in plant procedures.

The subsequent Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.4.12.4 Verification that the PORV block valve is open ensures a flow path to the PORV.

The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.4.12.5 A CHANNEL FUNCTIONAL TEST is required periodically. PORV actuation is not needed, as it could depressurize the RCS.

The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.4.12.6 Verification that administrative controls, other than limits for pressurizer level, that assure > 10 minutes are available for operator action to mitigate the consequences of an LTOP event are implemented is necessary periodically. This verification consists of a combination of administrative checks for alarm availability, verification that pressurizer heater bank 3 or 4 is deactivated, appropriate restrictions on pressurizer level, controls for High Pressure Nitrogen, etc., as well as visual confirmation using available indications that associated physical parameters are within limits.

OCONEE UNITS 1, 2, & 3 B 3.4.12-11 BASES REVISION DATED 04/18/14 I

LTOP System B 3.4.12 BASES SURVEILLANCE SR 3.4.12.6 (continued)

REQUIREMENTS The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.4.12.7 The CHANNEL CALIBRATION for the LTOP setpoint ensures that the PORV will be actuated at the appropriate RCS pressure by verifying the accuracy of the instrument string.

The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

REFERENCES 1. 10 CFR 50, Appendix G.

2. Generic Letter 88-11.

3. UFSAR, 5.2.3.7.

4. 10 CFR 50.36.

OCONEE UNITS 1, 2, &3 B 3.4.12-12 BASES REVISION DATED 04/18/14 I