CNS-14-055, Technical Specification Bases Changes

Technical Specification Bases Changes

ML14127A436
Person / Time
Site:	Catawba
Issue date:	05/05/2014
From:	Henderson K Duke Energy Corp
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
CNS-14-055
Download: ML14127A436 (36)

Text

~ENERGY.

Kelvin Henderson Vice President Catawba Nuclear Station Duke Energy CN01VP I 4800 Concord Road York, SC 29745 CNS-14-055 o: 803.701.4251 f: 803.701.3221 May 5, 2014 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001

Subject:

Duke Energy Carolinas, LLC Catawba Nuclear Station, Units 1 and 2 Docket Nos. 50-413 and 50-414 Technical Specification Bases Changes Pursuant to 10CFR 50.4, please find attached changes to the Catawba Nuclear Station Technical Specification Bases. These Bases changes were made according to the provisions of Technical Specification 5.5.14, "Technical Specifications (TS) Bases Control Program."

Any questions regarding this information should be directed to Larry Rudy, Regulatory Affairs, at (803) 701-3084.

I certify that I am a duly authorized officer of Duke Energy Carolinas, LLC, and that the information contained herein accurately represents changes made to the Technical Specification Bases since the previous submittal.

Kelvin Henderson Vice President, Catawba Nuclear Station Attachment AooI www.duke-energy.com

U.S. Nuclear Regulatory Commission May 5, 2014 Page 2 xc:

V. M. 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. G.E. Miller NRC Project Manager (CNS)

U.S. Nuclear Regulatory Commission One White Flint North, Mail Stop O-8G9A 11555 Rockville Pike Rockville, MD 20852-2746 G. A. Hutto, Senior Resident Inspector Catawba Nuclear Station

~ENERGY.

Catawba Nuclear Station Duke Energy CN01VP I 4800 Concord Road York, SC 29745 May 5, 2014 Re:

Catawba Nuclear Station Technical Specifications Bases Please replace the corresponding pages in your copy of the Catawba Technical Specifications Manual as follows:

REMOVE THESE PAGES INSERT THESE PAGES LIST OF EFFECTIVE PAGES Entire Bases Section (pages 13 - 19)

Entire Bases Section (pages 13 - 19)

TAB 3.3.3 B 3.3.3-1 thru B 3.3.3-16 Revision 5 B 3.3.3-1 thru B 3.3.3-16 Revision 6 TAB 3.5.4 B 3.5.4-1 thru B 3.5.4-6 Revision 4 B 3.5.4-1 thru B 3.5.4-5 Revision 5 TAB 3.6.14 B 3.6.14-1 thru B 3.6.14-5 Revision 1 B 3.6.14-1 thru B 3.6.14-5 Revision 2 If you have any questions concerning the contents of this Technical Specification update, contact Kristi Byers at (803)701-3758.

Randy Hart Manager, Regulatory Compliance www.duke-energy.com

ii iii B 2.1.1-1 B 2.1.1-2 B 2.1.1-3 B 2.1.2-1 B 2.1.2-2 B 2.1.2-3 B 3.0-1 B 3.0-2 B 3.0-3 B 3.0-4 B 3.0-5 B 3.0-6 B 3.0-7 B 3.0-8 B 3.0-9 B 3.0-10 B 3.0-11 B 3.0-12 B 3.0-13 B 3.0-14 B 3.0-15 B 3.0-16 B 3.0-17 B 3.0-18 B 3.0-19 B 3.1.1-1 thru B 3.1.1-6 BASES Revision 1 Revision 2 Revision I Revision 0 Revision 1 Revision 1 Revision 0 Revision 0 Revision 0 Revision 1 Revision 1 Revision 2 Revision 3 Revision 3 Revision 2 Revision 2 Revision 3 Revision 2 Revision 3 Revision 3 Revision 3 Revision 3 Revision 3 Revision 1 Revision 1 Revision 0 Revision 0 Revision 0 Revision 3 4/08/99 3/01/05 6/21/04 9/30/98 12/19/03 12/19/03 9/30/98 9/30/98 9/30/98 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 3/19/07 5/05/11 Catawba Units 1 and 2 Page 13 4/11/14

B 3.1.2-1 thru B 3.1.2-5 B 3.1.3-1 B 3.1.3-2 B 3.1.3-3 B 3.1.3-4 B 3.1.3-5 B 3.1.3-6 B 3.1.4-1 thru B 3.1.4-9 B 3.1.5-1 thru B 3.1.5-4 B 3.1.6-1 thru B 3.1.6-6 B 3.1.7-1 B 3.1.7-2 B 3.1.7-3 B 3.1.7-4 B 3.1.7-5 B 3.1.7-6 B 3.1.8-1 thru B 3.1.8-6 B 3.2.1-1 thru B 3.2.1.-11 B 3.2.2-1 thru B 3.2.2-10 B 3.2.3-1 thru B 3.2.3-4 B 3.2.4-1 thru B 3.2.4-7 B 3.3.1-1 thru B.3.3.1-55 B 3.3.2-1 thru B 3.3.2-49 B 3.3.3-1 thru B.3.3.3-16 B 3.3.4-1 thru B 3.3.4-5 Revision 2 Revision 1 Revision 1 Revision 1 Revision 1 Revision 1 Revision 1 Revision 1 Revision 2 Revision 1 Revision 0 Revision 2 Revision 2 Revision 2 Revision 2 Revision 2 Revision 2 Revision 4 Revision 3 Revision 2 Revision 2 Revision 7 Revision 10 Revision 6 Revision 2 5/05/11 4/26/00 4/26/00 4/26/00 4/26/00 4/26/00 4/26/00 5/05/11 5/05/11 5/05/11 9/30/98 1/08/04 1/08/04 1/08/04 1/08/04 1/08/04 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 11/15/11 5/05/11 4/11/14 5/05/11 Catawba Units 1 and 2 Page 14 4/11/14

B 3.3.5-1 thru B 3.3.5-6 B 3.3.6-1 thru B 3.3.6-5 B 3.3.9-1 thru B 3.3.9-5 B 3.4.1-1 thru B 3.4.1-5 B 3.4.2-1 B 3.4.2-2 B 3.4.2-3 B 3.4.3-1 thru B 3.4.3-6 B 3.4.4-1 thru B 3.4.4-3 B 3.4.5-1 thru B 3.4.5-6 B 3.4.6-1 thru B 3.4.6-5 B 3.4.7-1 thru B 3.4.7-5 B 3.4.8-1 thru B 3.4.8-3 B 3.4.9-1 thru B 3.4.9-5 B 3.4.10-1 B 3.4.10-2 B 3.4.10-3 B 3.4.10-4 B 3.4.11-1 thru B 3.4.11-7 B 3.4.12-1 thru B 3.4.12-13 5 3.4.13-1 thru B 3.4.13-7 B 3.4.14-1 thru B 3.4.14-6 B 3.4.15-1 thru B 3.4.15-10 Catawba Units 1 and 2 Revision 2 Revision 6 Revision 2 Revision 3 Revision 0 Revision 0 Revision 0 Revision 2 Revision 2 Revision 3 Revision 4 Revision 5 Revision 3 Revision 3 Revision 1 Revision 0 Revision I Revision 2 Revision 4 Revision 4 Revision 7 Revision 3 Revision 6 5/05/11 08/02/12 5/05/11 5/05/11 9/30/98 9/30/98 9/30/98 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 08/02/12 3/4/04 9/30/98 3/4/04 10/30/09 5/05/11 5/05/11 3/15/12 5/05/11 5/05/11 Page 15 4/11/14

B 3.4.16-1 thru B 3.4.16-5 B 3.4.17-1 thru B 3.4.17-3 B 3.4.18-1 B 3.4.18-2 B 3.4.18-3 B 3.4.18-4 B 3.4.18-5 B 3.4.18-6 B 3.4.18-7 B 3.4.18-8 B 3.5.1-1 thru B 3.5.1-8 B 3.5.2-1 thru B 3.5.2-10 B 3.5.3-1 B 3.5.3-2 B 3.5.3-3 B 3.5.4-1 thru B.3.5.4-5 B 3.5.5-1 thru B 3.5.5-4 B 3.6.1-1 B 3.6.1-2 B 3.6.1-3 B 3.6.1-4 B 3.6.1-5 B 3.6.2-1 thru B 3.6.2-8 B 3.6.3-1 thru B 3.6.3-14 B 3.6.4-1 thru B 3.6.4-4 B 3.6.5-1 thru B 3.6.5-4 Revision 4 Revision 2 Revision 0 Revision 0 Revision 1 Revision 0 Revision 0 Revision 0 Revision 0 Revision I Revision 3 Revision 3 Revision 0 Revision 1 Revision 1 Revision 5 Revision 1 Revision 1 Revision 1 Revision 1 Revision 1 Revision 1 Revision 2 Revision 4 Revision 2 Revision 3 10/23/12 5/05/11 1/13/05 1/13/05 3/18/08 1/13/05 1/13/05 1/13/05 1/13/05 3/18/08 5/05/11 5/05/11 9/30/98 4/29/04 4/29/04 4/11/14 5/05/11 7/31/01 7/31/01 7/31/01 7/31/01 7/31/01 5/05/11 5/05/11 5/05/11 07/27/13 Catawba Units 1 and 2 Page 16 4/11/14

B 3.6.6-1 thru B 3.6.6-7 B 3.6.8-1 thru B 3.6.8-5 B 3.6.9-1 thru B 3.6.9-5 B 3.6.10-1 thru B 3.6.10-6 B 3.6.11-1 thru B 3.6.11-6 B 3.6.12-1 thru B 3.6.12-11 B 3.6.13-1 thru B 3.6.13-9 B 3.6.14-1 thru B 3.6.14-5 B 3.6.15-1 thru B 3.6.15-4 B 3.6.16-1 thru B 3.6.16-4 B 3.6.17-1 B 3.6.17-2 B 3.6.17-3 B 3.6.17-4 B 3.6.17-5 B 3.7.1-1 B 3.7.1-2 B 3.7.1-3 B 3.7.1-4 B 3.7.1-5 B 3.7.2-1 B 3.7.2-2 B 3.7.2-3 B 3.7.2-4 B 3.7.2-5 B 3.7.3-1 B 3.7.3-2 Catawba Units 1 and 2 Revision 6 Revision 3 Revision 6 Revision 2 Revision 5 Revision 5 Revision 4 Revision 2 Revision 1 Revision 3 Revision 1 Revision 0 Revision 0 Revision 0 Revision 1 Revision 0 Revision 0 Revision 0 Revision 1 Revision 1 Revision 0 Revision 0 Revision 2 Revision 1 Revision 3 Revision 0 Revision 0 Page 17 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 4/11/14 5/05/11 5/05111 3/13/08 9/30/98 9/30/98 9/30/98 3/13/08 9/30/98 9/30/98 9/30/98 10/30/09 10/30/09 9/30/98 9/30/98 6/23/10 9/08/08 10/30/09 9/30/98 9/30/98 4/11/14

B 3.7.3-3 B 3.7.3-4 B 3.7.3-5 B 3.7.3-6 B 3.7.4-1 thru B 3.7.4-4 B 3.7.5-1 thru B 3.7.5-9 B 3.7.6-1 thru B 3.7.6-3 B 3.7.7-1 thru B 3.7.7-5 B 3.7.8-1 thru B 3.7.8-8 B 3.7.9-1 thru B 3.7.9-4 B 3.7.10-1 thru B 3.7.10-9 B 3.7.11-1 thru B 3.7.11-4 B 3.7.12-1 thru B 3.7.12-7 B 3.7.13-1 thru B 3.7.13-5 B 3.7.14-1 thru B 3.7.14-3 B 3.7.15-1 thru B 3.7.15-4 B 3.7.16-1 B 3.7.16-2 B 3.7.16-3 B 3.7.16-4 B 3.7.17-1 thru B 3.7.17-3 B 3.8.1-1 thru B.3.8.1-29 B 3.8.2-1 B 3.8.2-2 Revision 0 Revision 0 Revision 1 Revision 2 Revision 2 Revision 3 Revision 4 Revision 2 Revision 5 Revision 3 Revision 10 Revision 3 Revision 6 Revision 4 Revision 2 Revision 2 Revision 2 Revision 2 Revision 2 Revision 0 Revision 2 Revision 5 Revision 0 Revision 0 9/30/98 9/30/98 9/08/08 10/30/09 5/05/11 5/05/11 08/02/12 5/05/11 08/09/13 5/05/11 10/24/11 10/24/11 1/09/13 5/05/11 5/05/11 5/05/11 9/27/06 9/27/06 9/27/06 9/27/06 5/05/11 07/27/13 9/30/98 9/30/98 Catawba Units 1 and 2 Page 18 4/11/14

B 3.8.2-3 B 3.8.2-4 B 3.8.2-5 B 3.8.2-6 B 3.8.3-1 thru B 3.8.3-8 B 3.8.4-1 thru B3.8.4. 10 B 3.8.5-1 B 3.8.5-2 B 3.8.5-3 B 3.8.6-1 thru B 3.8.6-7 B 3.8.7-1 thru B 3.8.7-4 B 3.8.8-1 thru B 3.8.8-4 B 3.8.9-1 thru B 3.8.9-10 B 3.8.10-1 thru B 3.8.10-4 B 3.9.1-1 thru B 3.9.1-4 B 3.9.2-1 thru B 3.9.2.4 B 3.9.3-1 thru B 3.9.3-5 B 3.9.4-1 thru B 3.9.4-4 B 3.9.5-1 thru B 3.9.5-4 B 3.9.6-1 thru B 3.9.6-3 B 3.9.7-1 thru B 3.9.7-3 Revision 0 Revision 1 Revision 2 Revision 1 Revision 4 Revision 10 Revision 0 Revision 2 Revision 1 Revision 4 Revision 3 Revision 3 Revision 2 Revision 3 Revision 3 Revision 4 Revision 4 Revision 4 Revision 3 Revision 2 Revision 1 9/30/98 5/10/05 5/10/05 5/10/05 5/05/11 5/05/11 9/30/98 7/29/03 7/29/03 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 5/05/11 0

Catawba Units 1 and 2 Page 19 4/11/14

PAM Instrumentation B 3.3.3 B 3.3 INSTRUMENTATION B 3.3.3 Post Accident Monitoring (PAM) Instrumentation BASES BACKGROUND The primary purpose of the PAM instrumentation is to display unit variables that provide information required by the control room operators during accident situations. This information provides the necessary support for the operator to take the manual actions for which no automatic control is provided and that are required for safety systems to accomplish their safety functions for Design Basis Accidents (DBAs).

The OPERABILITY of the accident monitoring instrumentation ensures that there is sufficient information available on selected unit parameters to monitor and to assess unit status and behavior following an accident.

The availability of accident monitoring instrumentation is important so that responses to corrective actions can be observed and the need for, and magnitude of, further actions can be determined. These essential instruments are identified by unit specific documents (Ref. 1) addressing the recommendations of Regulatory Guide 1.97 (Ref. 2) as required by Supplement 1 to NUREG-0737 (Ref. 3).

The instrument channels required to be OPERABLE by this LCO include two classes of parameters identified during unit specific implementation of Regulatory Guide 1.97 as Type A and Category I variables.

Type A variables are included in this LCO because they provide the primary information required for the control room operator to take specific manually controlled actions for which no automatic control is provided, and that are required for safety systems to accomplish their safety functions for DBAs.

Category I variables are the key variables deemed risk significant because they are needed to:

0 Catawba Units 1 and 2 B 3.3.3-1 Revision No. 6

PAM Instrumentation B 3.3.3 BASES BACKGROUND (continued)

Determine whether other systems important to safety are performing their intended functions; Provide information to the operators that will enable them to determine the likelihood of a gross breach of the barriers to radioactivity release; and Provide information regarding the release of radioactive materials to allow for early indication of the need to initiate action necessary to protect the public, and to estimate the magnitude of any impending threat.

These key variables are identified by the unit specific Regulatory Guide 1.97 analyses (Ref. 1). These analyses identify the unit specific Type A and Category I variables and provide justification for deviating from the NRC proposed list of Category I variables.

The specific instrument Functions listed in Table 3.3.3-1 are discussed in the LCO section.

APPLICABLE The PAM instrumentation ensures the operability of Regulatory SAFETY ANALYSES Guide 1.97 Type A and Category I variables so that the control room operating staff can:

Perform the diagnosis specified in the emergency operating procedures (these variables are restricted to preplanned actions for the primary success path of DBAs), e.g., loss of coolant accident (LOCA);

Take the specified, pre-planned, manually controlled actions, for which no automatic control is provided, and that are required for safety systems to accomplish their safety function; Determine whether systems important to safety are performing their intended functions; Determine the likelihood of a gross breach of the barriers to radioactivity release; Catawba Units 1 and 2 B 3.3.3-2 Revision No. 6

PAM Instrumentation B 3.3.3 BASES APPLICABLE SAFETY ANALYSES (continued)

Determine if a gross breach of a barrier has occurred; and Initiate action necessary to protect the public and to estimate the magnitude of any impending threat.

PAM instrumentation that meets the definition of Type A in Regulatory Guide 1.97 satisfies Criterion 3 of 10 CFR 50.36 (Ref. 4). Category I, non-Type A, instrumentation must be retained in TS because it is intended to assist operators in minimizing the consequences of accidents. Therefore, Category I, non-Type A, variables are important for reducing public risk.

LCO The PAM instrumentation LCO provides OPERABILITY requirements for Regulatory Guide 1.97 Type A monitors, which provide information required by the control room operators to perform certain manual actions specified in the unit Emergency Operating Procedures. These manual actions ensure that a system can accomplish its safety function, and are credited in the safety analyses. Additionally, this LCO addresses Regulatory Guide 1.97 instruments that have been designated Category I, non-Type A.

The OPERABILITY of the PAM instrumentation ensures there is sufficient information available on selected unit parameters to monitor and assess unit status following an accident. This capability is consistent with the recommendations of Reference 1.

LCO 3.3.3 requires two OPERABLE channels for most Functions. Two OPERABLE channels ensure no single failure prevents operators from getting the information necessary for them to determine the safety status of the unit, and to bring the unit to and maintain it in a safe condition following an accident.

Furthermore, OPERABILITY of two channels allows a CHANNEL CHECK during the post accident phase to confirm the validity of displayed information.

In some cases, the total number of channels exceeds the number of required channels, e.g., pressurizer level has a total of three Catawba Units 1 and 2 B 3.3.3-3 Revision No. 6

PAM Instrumentation B 3.3.3 BASES LCO (continued) channels, however only two channels are required OPERABLE. This provides additional redundancy beyond that required by this LCO, i.e.,

when one channel of pressurizer level is inoperable, the required number of two channels can still be met. The ACTIONS of this LCO are only entered when the required number of channels cannot be met.

Type A and Category I variables are required to meet Regulatory Guide 1.97 Category I (Ref. 2) design and qualification requirements for seismic and environmental qualification, single failure criterion, utilization of emergency standby power, immediately accessible display, continuous readout, and recording of display.

Performing the Neutron Flux Instrumentation and Containment Area Radiation (High-Range) surveillances meets the License Renewal Commitments for License Renewal Program for High-Range Radiation and Neutron Flux Instrumentation Circuits per UFSAR Chapter 18, Table 18-1 and License Renewal Commitments specification CNS-1274.00 0016.

Listed below are discussions of the specified instrument Functions listed in Table 3.3.3-1.

1, 2.

Reactor Coolant System (RCS) Hot and Cold Leg Temperatures RCS Hot and Cold Leg Temperatures are Category I variables provided for verification of core cooling and long term surveillance.

RCS hot and cold leg temperatures are used to determine RCS subcooling margin. RCS subcooling margin will allow termination of safety injection (SI), if still in progress, or reinitiation of SI if it has been stopped. RCS subcooling margin is also used for unit stabilization and cooldown control.

In addition, RCS cold leg temperature is used in conjunction with RCS hot leg temperature to verify the unit conditions necessary to establish natural circulation in the RCS.

Reactor coolant hot and cold leg temperature inputs are provided by a fast response resistance element in each loop.

RCS Hot and Cold Leg Temperature are diverse indications of RCS temperature. Core exit thermocouples also provide diverse indication of RCS temperature.

0 Catawba Units 1 and 2 B 3.3.3-4 Revision No. 6

PAM Instrumentation B 3.3.3 BASES LCO (continued)

3.

Reactor Coolant System Pressure (Wide Range)

RCS wide range pressure is a Category I variable provided for verification of core cooling and RCS integrity long term surveillance.

RCS pressure is used to verify delivery of SI flow to RCS from at least one train when the RCS pressure is below the pump shutoff head. RCS pressure is also used to verify closure of manually closed spray line valves and pressurizer power operated relief valves (PORVs).

In addition to these verifications, RCS pressure is used for determining RCS subcooling margin. RCS pressure can also be used:

to determine whether to terminate actuated SI or to reinitiate stopped SI; to determine when to reset SI and shut off low head SI; to manually restart low head SI; as reactor coolant pump (RCP) trip criteria; and to make a determination on the nature of the accident in progress and where to go next in the procedure.

RCS pressure is also related to three decisions about depressurization. They are:

to determine whether to proceed with primary system depressurization; to verify termination of depressurization; and to determine whether to close accumulator isolation valves during a controlled cooldown/depressurization.

Catawba Units 1 and 2 B 3.3.3-5 Revision No. 6

PAM Instrumentation B 3.3.3 BASES LCO (continued)

A final use of RCS pressure is to determine whether to operate the pressurizer heaters.

RCS pressure is a Type A variable because the operator uses this indication to monitor the cooldown of the RCS following a steam generator tube rupture (SGTR) or small break LOCA. Operator actions to maintain a controlled cooldown, such as adjusting steam generator (SG) pressure or level, would use this indication.

Furthermore, RCS pressure is one factor that may be used in decisions to terminate RCP operation.

Two channels of wide range RCS pressure are required OPERABLE.

4.

Reactor Vessel Water Level Reactor Vessel Water Level is provided for verification and long term surveillance of core cooling. It is also used for accident diagnosis and to determine reactor coolant inventory adequacy.

The Reactor Vessel Water Level Monitoring System provides a direct measurement of the collapsed liquid level above the fuel alignment plate. The collapsed level represents the amount of liquid mass that is in the reactor vessel above the core.

Measurement of the collapsed water level is selected because it is a direct indication of the water inventory.

Two channels of Reactor Vessel Water Level are required with plasma displays in the unit control room. Each channel consists of three differential pressure transmitters and a micro processor to calculate true vessel level or relative void content of the primary coolant.

5.

Containment Sump Water Level (Wide Range)

Containment Sump Water Level is provided for verification and long term surveillance of RCS integrity.

Catawba Units 1 and 2 B 3.3.3-6 Revision No. 6

PAM Instrumentation B 3.3.3 BASES LCO (continued)

Containment Sump Water Level is used to determine:

containment sump level accident diagnosis; when to begin the recirculation procedure; and whether to terminate SI, if still in progress.

Two channels of Wide Range Containment Sump Water Level are required OPERABLE. Each channel consists of wide range containment sump level indication, and two level switches.

6.

Containment Pressure (Wide Range)

Containment Pressure (Wide Range) is provided for verification of RCS and containment OPERABILITY.

Containment pressure is used to verify closure of main steam isolation valves (MSIVs), containment spray operation, and Phase B containment isolation when Containment Pressure - High High is reached.

Two channels of wide range containment pressure are required OPERABLE.

7.

Containment Area Radiation (Hi-gh Range)

Containment Area Radiation is provided to monitor for the potential of significant radiation releases and to provide release assessment for use by operators in determining the need to invoke site emergency plans. Containment radiation level is used to determine if a high energy line break (HELB) has occurred, and whether the event is inside or outside of containment.

Two channels of high range containment area radiation are provided. One channel is required OPERABLE. Diversity or backup information is provided by portable instrumentation or by sampling and analysis.

Catawba Units 1 and 2 B 3.3.3-7 Revision No. 6

PAM Instrumentation B 3.3.3 BASES LCO (continued)

8.

Not Used

9.

Pressurizer Level Pressurizer Level is used to determine whether to terminate SI, if still in progress, or to reinitiate SI if it has been stopped.

Knowledge of pressurizer water level is also used to verify the unit conditions necessary to establish natural circulation in the RCS and to verify that the unit is maintained in a safe shutdown condition.

Three channels of pressurizer level are provided. Two channels are required OPERABLE.

10.

Steam Generator Water Level (Narrow Range)

SG Water Level is provided to monitor operation of decay heat removal via the SGs. The Category I indication of SG level is the narrow range level instrumentation.

SG Water Level (Narrow Range) is used to:

identify the faulted SG following a tube rupture; verify that the intact SGs are an adequate heat sink for the reactor; determine the nature of the accident in progress (e.g., verify an SGTR); and verify unit conditions for termination of SI during secondary unit HELBs outside containment.

Four channels per SG of narrow range water level are provided.

Only two channels are required OPERABLE by the LCO.

Catawba Units 1 and 2 B 3.3.3-8 Revision No. 6

PAM Instrumentation B 3.3.3 BASES S

LCO (continued) 11, 12, 13, 14.

Core Exit Temperature Core Exit Temperature is provided for verification and long term surveillance of core cooling.

Adequate core cooling is ensured with two valid Core Exit Temperature channels per quadrant with two CETs per required channel. Core inlet temperature data is used with core exit temperature to give radial distribution of coolant enthalpy rise across the core. Core Exit Temperature is used to determine whether to terminate SI, if still in progress, or to reinitiate SI if it has been stopped. Core Exit Temperature is also used for unit stabilization and cooldown control.

Two OPERABLE channels of Core Exit Temperature are required in each quadrant to provide indication of radial distribution of the coolant temperature rise across representative regions of the core.

Two sets of two thermocouples (1 set per redundant power train) ensure a single failure will not disable the ability to determine the radial temperature gradient.

15.

Auxiliary Feedwater Flow AFW Flow is provided to monitor operation of decay heat removal via the SGs.

The AFW flow to each SG is determined by flow indicators, pump operational status indicators, and NSWS and condensate supply valve indicators in the control room. The AFW flow indicators are category 2, type D variables which are used to demonstrate the AFW assured source.

AFW flow is used three ways:

to verify delivery of AFW flow to the SGs; to determine whether to terminate SI if still in progress, in conjunction with SG water level (narrow range); and to regulate AFW flow so that the SG tubes remain covered.

0 Catawba Units 1 and 2 B 3.3.3-9 Revision No. 6

PAM Instrumentation B 3.3.3 BASES LCO (continued)

One channel per SG of AFW flow is required to be OPERABLE.

Diverse indication of AFW flow is provided by SG level.

16.

RCS Radiation Level The RCS radiation monitor provides indication of radiation levels within the primary coolant and alerts the operator to possible fuel clad failures.

One channel of RCS radiation level is required OPERABLE. This monitor was not installed to quantify accident conditions and cannot be assured flow following an accident. Diverse or backup information for this variable is provided by sampling and analysis of the primary coolant.

17.

RCS Subcooling Margin Monitor RCS subcooling margin monitoring indication is provided to allow unit stabilization and cooldown control. RCS subcooling margin monitoring indication will provide information to the operators to allow termination of SI, if still in progress, or reinitiation of SI if it has been stopped.

The margin to saturation is calculated from RCS pressure and temperature measurements. The average of the five highest core exit thermocouples are used to represent core conditions and the wide range hot leg RTDs are used to measure loop hot leg temperatures. The ICCM System performs the calculations and comparisons to saturation curves. A graphic display over the required range gives the operator a representation of primary system conditions compared to various curves of importance (saturation, NDT, etc.). Two trains of RCS Subcooling Margin Monitor are provided and two trains are required to be OPERABLE.

A backup program exists to ensure the capability to accurately monitor RCS subcooling. The program includes training and a procedure to manually calculate subcooling margin, using control room pressure and temperature instruments.

18.

Steam Line Pressure Steam Line Pressure is provided to monitor operation of decay heat removal via the SGs. Steam line pressure is also used to determine if a high energy secondary line rupture occurred and which SG is faulted.

Catawba Units 1 and 2 B 3.3.3-10 Revision No. 6

PAM Instrumentation B 3.3.3 BASES LCO (continued)

There are three channels of Steam Line Pressure provided for each SG. Two channels per SG are required OPERABLE by the LCO.

19.

Refuelinq Water Storage Tank Level RWST level monitoring is provided to ensure an adequate supply of water to the ECCS pumps during the switchover to cold leg recirculation.

Four channels of RWST level are provided. Only two channels are required OPERABLE by the LCO.

20.

Neutron Flux (Wide Range)

Wide Range Neutron Flux indication is provided to verify reactor shutdown.

Neutron flux is used for accident diagnosis, verification of subcriticality, and diagnosis of positive reactivity insertion.

Two channels of wide range neutron flux are required OPERABLE.

21.

Steam Generator Water Level (Wide Range)

SG Water Level (Wide Range) is used to verify that the intact SGs are an adequate heat sink for the reactor. One channel per steam generator is required OPERABLE by the LCO. Diverse indication is provided by Steam Generator Water Level (Narrow Range).

APPLICABILITY The PAM instrumentation LCO is applicable in MODES 1, 2, and 3.

These variables are related to the diagnosis and pre-planned actions required to mitigate DBAs. The applicable DBAs are assumed to occur in MODES 1, 2, and 3. In MODES 4, 5, and 6, unit conditions are such that the likelihood of an event that would require PAM instrumentation is low; therefore, the PAM instrumentation is not required to be OPERABLE in these MODES.

Catawba Units 1 and 2 B 3.3.3-11 Revision No. 6

PAM Instrumentation B 3.3.3 BASES ACTIONS A Note has been added in the ACTIONS to clarify the application of Completion Time rules. The Conditions of this Specification may be entered independently for each Function listed on Table 3.3.3-1. When the Required Channels in Table 3.3.3-1 are specified (e.g., on a per steam line, per loop, per SG, etc., basis), then the Condition may be entered separately for each steam line, loop, SG, etc., as appropriate.

The Completion Time(s) of the inoperable channel(s) of a Function will be tracked separately for each Function starting from the time the Condition was entered for that Function.

A..1 Condition A applies to all PAM instrument Functions. Condition A addresses the situation when one or more required channels for one or more Functions are inoperable. The Required Action is to refer to Table 3.3.3-1 and take the appropriate Required Actions for the PAM instrumentation affected. The Completion Times are those from the referenced Conditions and Required Actions.

B. 1 Condition B applies when one or more Functions have one required channel that is inoperable. Required Action A.1 requires restoring the inoperable channel to OPERABLE status within 30 days. The 30 day Completion Time is based on operating experience and takes into account the remaining OPERABLE channel, the passive nature of the instrument (no critical automatic action is assumed to occur from these instruments), and the low probability of an event requiring PAM instrumentation during this interval.

Catawba Units 1 and 2 B 3.3.3-12 Revision No. 6

PAM Instrumentation B 3.3.3 BASES ACTIONS (continued)

C..1 Condition C applies to PAM Instrument Functions when a single required channel is inoperable and a diverse channel for the affected function remains OPERABLE. The Required Action requires the affected channel be restored to OPERABLE status within 30 days. The 30 day Completion Time is based on operating experience and takes into account the remaining OPERABLE diverse channel, the passive nature of the instrument (no critical automatic action is assumed to occur from these instruments), and the low probability of an event requiring PAM instrumentation during this interval.

D._1 Condition D applies when the Required Action and associated Completion Time for Condition B or C are not met. This Required Action specifies initiation of actions in Specification 5.6.7, which requires a written report to be submitted to the NRC immediately. This report discusses the results of the root cause evaluation of the inoperability and identifies proposed restorative actions. This action is appropriate in lieu of a shutdown requirement since alternative actions are identified before loss of functional capability, and given the likelihood of unit conditions that would require information provided by this instrumentation.

E.1 and E.2 Condition E applies when a single required channel is inoperable and no diverse channel is OPERABLE. Required Action E.1 and E.2 requires restoring the required channel or the diverse channel to OPERABLE status within 7 days. The Completion Time of 7 days is based on the relatively low probability of an event requiring PAM instrument operation and the availability of alternate means to obtain the required information.

Continuous operation with the required channel and the diverse channel inoperable is not acceptable. Therefore, requiring restoration of either the required or diverse channel to OPERABLE status limits the risk that the PAM function will be in a degraded condition should an event occur.

Catawba Units 1 and 2 B 3.3.3-13 Revision No. 6

PAM Instrumentation B 3.3.3 BASES ACTIONS (continued)

F. 1 Condition F applies when one or more Functions have two inoperable required channels (i.e., two channels inoperable in the same Function).

Required Action F.1 requires restoring one channel in the Function(s) to OPERABLE status within 7 days. The Completion Time of 7 days is based on the relatively low probability of an event requiring PAM instrument operation and the availability of alternate means to obtain the required information. Continuous operation with two required channels inoperable in a Function is not acceptable because the alternate indications may not fully meet all performance qualification requirements applied to the PAM instrumentation. Therefore, requiring restoration of one inoperable channel of the Function limits the risk that the PAM Function will be in a degraded condition should an accident occur.

G.1 Not Used H.1 and H.2 If the Required Action and associated Completion Time of Conditions E or F are not met, the unit must be brought to a MODE where the requirements of this LCO do not apply. To achieve this status, the unit must be brought to at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and MODE 4 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

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

0 Catawba Units 1 and 2 B 3.3.3-14 Revision No. 6

PAM Instrumentation B 3.3.3 BASES SURVEILLANCE A Note has been added to the SR Table to clarify that SR 3.3.3.1 and REQUIREMENTS SR 3.3.3.3 apply to each PAM instrumentation Function in Table 3.3.3-1.

SR 3.3.3.1 Performance of the CHANNEL CHECK ensures that a gross instrumentation failure has not occurred. A CHANNEL CHECK is normally a comparison of the parameter indicated on one channel to a similar parameter on other channels. It is based on the assumption that instrument channels monitoring the same parameter should read approximately the same value. Significant deviations between the two instrument channels could be an indication of excessive instrument drift in one of the channels or of something even more serious. A CHANNEL CHECK will detect gross channel failure; thus, it is key to verifying the instrumentation continues to operate properly between each CHANNEL CALIBRATION. The high radiation instrumentation should be compared to similar unit instruments located throughout the unit.

Agreement criteria are determined by the unit staff, based on a combination of the channel instrument uncertainties, including isolation, indication, and readability. If a channel is outside the criteria, it may be an indication that the sensor or the signal processing equipment has drifted outside its limit. If the channels are within the criteria, it is an indication that the channels are OPERABLE.

As specified in the SR, a CHANNEL CHECK is only required for those channels that are normally energized.

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

SR 3.3.3.2 Not Used Catawba Units 1 and 2 B 3.3.3-15 Revision No. 6

PAM Instrumentation B 3.3.3 BASES SURVEILLANCE REQUIREMENTS (continued)

SR 3.3.3.3 CHANNEL CALIBRATION is a complete check of the instrument loop, including the sensor. The test verifies that the channel responds to measured parameter with the necessary range and accuracy. This SR is modified by two Notes. Note 1 excludes neutron detectors. The calibration method for neutron detectors is specified in the Bases of LCO 3.3.1, "Reactor Trip System (RTS) Instrumentation." Note 2 describes the calibration methods for the Containment Area - High Range monitor.

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

REFERENCES

1.

UFSAR Section 1.8.

2.

Regulatory Guide 1.97, Rev. 2.

3.

NUREG-0737, Supplement 1, "TMI Action Items."

4.

10 CFR 50.36, Technical Specifications, (c)(2)(ii).

Catawba Units 1 and 2 B 3.3.3-16 Revision No. 6

RWST B 3.5.4 B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS)

B 3.5.4 Refueling Water Storage Tank (RWST)

BASES BACKGROUND The RWST supplies borated water to the Chemical and Volume Control System (CVCS) during abnormal operating conditions, to the refueling pool during refueling and makeup operations, and to the ECCS during accident conditions.

The RWST supplies both trains of the ECCS through separate supply headers during the injection phase of a loss of coolant accident (LOCA) recovery. A motor operated isolation valve is provided in each header to isolate the RWST once the system has been transferred to the recirculation mode. The recirculation mode is entered when pump suction is transferred to the containment sump following receipt of the RWST-Low Level signal. Use of a single RWST to supply both trains of the ECCS is acceptable since the RWST is a passive component, and since injection phase passive failures are not required to be assumed to occur coincidentally with Design Basis Events.

The switchover from normal operation to the injection phase of ECCS operation requires changing centrifugal charging pump suction from the CVCS volume control tank (VCT) to the RWST through the use of isolation valves.

During normal operation in MODES 1, 2, and 3, the safety injection (SI) and residual heat removal (RHR) pumps are aligned to take suction from the RWST.

The ECCS pumps are provided with recirculation lines that ensure each pump can maintain minimum flow requirements when operating at or near shutoff head conditions.

When the suction for the ECCS pumps is transferred to the containment sump, the RWST flow paths must be isolated to prevent a release of the containment sump contents to the RWST, which could result in a release of contaminants to the atmosphere and the eventual loss of suction head for the ECCS pumps.

This LCO ensures that:

a.

The RWST contains sufficient borated water to support the ECCS during the injection phase; Catawba Units 1 and 2 B 3.5.4-1 Revision No. 5

RWST B 3.5.4 BASES BACKGROUND (continued)

b.

Sufficient water volume exists in the containment sump to support continued operation of the ECCS and Containment Spray System pumps at the time of transfer to the recirculation mode of cooling; and

c.

The reactor remains subcritical following a LOCA.

Insufficient water in the RWST could result in insufficient cooling capacity when the transfer to the recirculation mode occurs. Improper boron concentrations could result in a reduction of SDM or excessive boric acid precipitation in the core following the LOCA, as well as excessive caustic stress corrosion of mechanical components and systems inside the containment.

APPLICABLE During accident conditions, the RWST provides a source of borated SAFETY ANALYSES water to the ECCS. As such, it provides core cooling and replacement inventory and is a source of negative reactivity for reactor shutdown (Ref. 1). The design basis transients and applicable safety analyses concerning each of these systems are discussed in the Applicable Safety Analyses section of B 3.5.2, "ECCS-Operating"; and B 3.5.3, "ECCS-Shutdown." These analyses are used to assess changes to the RWST in order to evaluate their effects in relation to the acceptance limits in the analyses.

The RWST must also meet volume, boron concentration, and temperature requirements for non-LOCA events. The volume is not an explicit assumption in non-LOCA events since the required volume is a small fraction of the available volume. The deliverable volume limit is set by the LOCA and containment analyses. For the RWST, the deliverable volume is different from the total volume contained due to the location of the piping connection. The ECCS water boron concentration is an explicit assumption in the main steam line break (MSLB) analysis to ensure the required shutdown capability. This assumption is important in ensuring the required shutdown capability. Although the maximum temperature is a conservative assumption in the feedwater line break analysis, SI termination occurs very quickly in this analysis and long before significant RCS heatup occurs. The minimum temperature, minus an allowance for temperature uncertainty, is an assumption in the MSLB core response, the Inadvertent Operation of a Steam Generator Relief or Safety Valve, the Inadvertent Operation of Emergency Core Cooling System, and the Steam Generator Tube Failure analyses.

Catawba Units 1 and 2 B 3.5.4-2 Revision No. 5

RWST B 3.5.4 BASES APPLICABLE SAFETY ANALYSES (continued)

For a large break LOCA analysis, the RWST level setpoint equivalent to the minimum water volume limit of 377,537 gallons and the lower boron concentration limits listed in the COLR are used to compute the post LOCA sump boron concentration necessary to assure subcriticality with all rods in, minus the highest worth rod out (ARI N-1). The large cold leg break LOCA is the limiting case since boron accumulation in the core will be maximized during the cold leg recirculation phase due to core boiling.

The accumulation of boron in the core prevents the boron from returning to the sump, which leads to a boron diluted sump condition that may cause the core to become re-critical when switching over to hot leg recirculation. For the post LOCA injection phase, each reload cycle is verified to have all rods out (ARO) critical boron concentrations less than the minimum allowed RWST boron concentration.

The upper limit on boron concentration as listed in the COLR is used to determine the maximum allowable time to switch to hot leg recirculation following a LOCA. The purpose of switching from cold leg to hot leg injection is to avoid boron precipitation in the core following the accident.

In addition, this upper limit ensures that the equilibrium pH of the solution in the containment sump following the design basis LOCA is at least 7.5.

The RWST upper temperature limit of 1 00°F, plus an allowance for temperature measurement uncertainty, is also used in the containment OPERABILITY analysis. Exceeding this temperature will result in higher containment pressures due to reduced containment spray cooling capacity. For the containment response following an MSLB, the lower limit on boron concentration and the upper limit on RWST water temperature are used to maximize the total energy release to containment.

The RWST satisfies Criterion 3 of 10 CFR 50.36 (Ref. 2).

LCO The RWST ensures that an adequate supply of borated water is available to cool and cover the core in the event of a LOCA, to maintain the reactor subcritical following a DBA, and to ensure adequate level in the containment sump to support ECCS and Containment Spray System pump operation in the recirculation mode.

To be considered OPERABLE, the RWST must meet the water volume, boron concentration, and temperature limits established in the SRs.

Catawba Units 1 and 2 B 3.5.4-3 Revision No. 5

RWST B 3.5.4 BASES APPLICABILITY In MODES 1, 2, 3, and 4, RWST OPERABILITY requirements are dictated by ECCS OPERABILITY requirements. Since the ECCS must be OPERABLE in MODES 1, 2, 3, and 4, the RWST must also be OPERABLE to support their operation. Core cooling requirements in MODE 5 are addressed by LCO 3.4.7, "RCS Loops-MODE 5, Loops Filled," and LCO 3.4.8, "RCS Loops-MODE 5, Loops Not Filled."

MODE 6 core cooling requirements are addressed by LCO 3.9.4, "Residual Heat Removal (RHR) and Coolant Circulation-High Water Level," and LCO 3.9.5, "Residual Heat Removal (RHR) and Coolant Circulation-Low Water Level."

ACTIONS A._1 With RWST boron concentration or borated water temperature not within limits, they must be returned to within limits within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. Under these conditions, the ECCS cannot perform its design function. Therefore, prompt action must be taken to restore the tank to OPERABLE condition.

The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> limit to restore the RWST temperature or boron concentration to within limits was developed considering the time required to change either the boron concentration or temperature and the fact that the contents of the tank are still available for injection.

B.1 With the RWST inoperable for reasons other than Condition A (e.g.,

water volume), it must be restored to OPERABLE status within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.

In this Condition, the ECCS cannot perform its design function.

Therefore, prompt action must be taken to restore the tank to OPERABLE status or to place the plant in a MODE in which the RWST is not required. The short time limit of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to restore the RWST to OPERABLE status is based on this condition simultaneously affecting redundant trains.

C.1 and C.2 If the RWST cannot be returned to OPERABLE status within the associated Completion Time, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-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 Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

Catawba Units 1 and 2 B 3.5.4-4 Revision No. 5

RWST B 3.5.4 BASES SURVEILLANCE SR 3.5.4.1 REQUIREMENTS The RWST borated water temperature should be verified to be within the limits assumed in the accident analyses band. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.5.4.2 The RWST water volume should be verified to be above the required minimum level plus instrument uncertainty in order to ensure that a sufficient initial supply is available for injection and to support continued ECCS and Containment Spray System pump operation on recirculation.

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

SR 3.5.4.3 The boron concentration of the RWST should be verified to be within the required limits. This SR ensures that the reactor will remain subcritical following a LOCA and that the boron content assumed for the injection water in the MSLB analysis is available. Further, it assures that the resulting sump pH will be maintained in an acceptable range so that boron precipitation in the core will not occur and the effect of chloride and caustic stress corrosion on mechanical systems and components will be minimized. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

REFERENCES

1.

UFSAR, Chapter 6 and Chapter 15.

2.

10 CFR 50.36, Technical Specifications, (c)(2)(ii).

Catawba Units 1 and 2 B 3.5.4-5 Revision No. 5

Divider Barrier Integrity B 3.6.14 B 3.6 CONTAINMENT SYSTEMS B 3.6.14 Divider Barrier Integrity BASES BACKGROUND The divider barrier consists of the operating deck and associated seals, personnel access doors, and equipment hatches that separate the upper and lower containment compartments. Divider barrier integrity is necessary to minimize bypassing of the ice condenser by the hot steam and air mixture released into the lower compartment during a Design Basis Accident (DBA). This ensures that most of the gases pass through the ice bed, which condenses the steam and limits pressure and temperature during the accident transient. Limiting the pressure and temperature reduces the release of fission product radioactivity from containment to the environment in the event of a DBA.

In the event of a DBA, the ice condenser inlet doors (located below the operating deck) open due to the pressure rise in the lower compartment.

This allows air and steam to flow from the lower compartment into the ice condenser. The resulting pressure increase within the ice condenser causes the intermediate deck doors and the door panels at the top of the condenser to open, which allows the air to flow out of the ice condenser into the upper compartment. The ice condenses the steam as it enters, thus limiting the pressure and temperature buildup in containment. The divider barrier separates the upper and lower compartments and ensures that the steam is directed into the ice condenser. The ice is adequate to absorb the initial blowdown of steam and water from a DBA as well as the additional heat loads that would enter containment following the initial blowdown. The additional heat loads would come from the residual heat in the reactor core, the hot piping and components, and the secondary system, including the steam generators. During the post blowdown period, the Air Return System (ARS) returns upper compartment air through the divider barrier to the lower compartment. This serves to equalize pressures in containment and to continue circulating heated air and steam from the lower compartment through the ice condenser, where the heat is removed by the remaining ice. After its initiation, the containment spray system also aids in heat removal.

Catawba Units 1 and 2 B 3.6.14-1 Revision No. 2

Divider Barrier Integrity B 3.6.14 BASES BACKGROUND (continued)

Divider barrier integrity ensures that the high energy fluids released during a DBA would be directed through the ice condenser and that the ice condenser would function as designed if called upon to act as a passive heat sink following a DBA.

APPLICABLE Divider barrier integrity ensures the functioning of the ice condenser SAFETY ANALYSES to the limiting containment pressure and temperature that could be experienced following a DBA. The limiting DBAs considered relative to containment temperature and pressure are the loss of coolant accident (LOCA) and the steam line break (SLB). The LOCA and SLB are analyzed using computer codes designed to predict the resultant containment pressure and temperature transients. DBAs are assumed not to occur simultaneously or consecutively.

Although the ice condenser is a passive system that requires no electrical power to perform its function, the Containment Spray System, RHR Spray System, and the ARS also function to assist the ice bed in limiting pressures and temperatures. Therefore, the postulated DBAs are analyzed, with respect to containment Engineered Safety Feature (ESF) systems, assuming the loss of one ESF bus, which is the worst case single active failure and results in the inoperability of one train in the Containment Spray System, RHR Spray System, and the ARS.

Additionally, a 5.0 ft2 opening is conservatively assumed to exist in the divider barrier in the LOCA and SLB DBA analyses.

The limiting DBA analyses (Ref. 1) show that the maximum peak containment pressure results from the LOCA analysis and is calculated to be less than the containment design pressure. The maximum peak containment temperature results from the SLB analysis and is discussed in the Bases for LCO 3.6.5, "Containment Air Temperature."

In addition to calculating the overall peak containment pressures, the DBA analyses include calculation of the transient differential pressures that occur across subcompartment walls during the initial blowdown phase of the accident transient. The internal containment walls and structures are designed to withstand these local transient pressure differentials for the limiting DBAs.

The divider barrier satisfies Criterion 3 of 10 CFR 50.36 (Ref. 2).

Catawba Units 1 and 2 B 3.6.14-2 Revision No. 2

Divider Barrier Integrity B 3.6.14 BASES LCO This LCO establishes the minimum equipment requirements to ensure that the divider barrier performs its safety function of ensuring that bypass leakage, in the event of a DBA, does not exceed the bypass leakage assumed in the accident analysis. Included are the requirements that the personnel access doors and equipment hatches in the divider barrier are OPERABLE and closed and that the divider barrier seal is properly installed and has not degraded with time. An exception to the requirement that the doors be closed is made to allow personnel transit entry through the divider barrier. The basis of this exception is the assumption that, for personnel transit, the time during which a door is open will be short (i.e., shorter than the Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for Condition A). The divider barrier functions with the ice condenser to limit the pressure and temperature that could be expected following a DBA.

APPLICABILITY In MODES 1, 2, 3, and 4, a DBA could cause an increase in containment pressure and temperature requiring the integrity of the divider barrier.

Therefore, the LCO is applicable in MODES 1, 2, 3, and 4.

The probability and consequences of these events in MODES 5 and 6 are low due to the pressure and temperature limitations of these MODES.

As such, divider barrier integrity is not required in these MODES.

ACTIONS A.1 If one or more personnel access doors or equipment hatches (other than the pressurizer enclosure hatch) are inoperable or open, except for personnel transit entry, 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> is allowed to restore the door(s) and equipment hatches to OPERABLE status and the closed position. The 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Completion Time is consistent with LCO 3.6.1, "Containment,"

which requires that containment be restored to OPERABLE status within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.

Condition A has been modified by a Note to provide clarification that, for this LCO, separate Condition entry is allowed for each personnel access door or equipment hatch.

B..1 If the pressurizer enclosure hatch is inoperable or open, 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> are allowed to restore the hatch to OPERABLE status and the closed position. The 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> completion time is based on the need to perform Catawba Units 1 and 2 B 3.6.14-3 Revision No. 2

Divider Barrier Integrity B 3.6.14 BASES ACTIONS (continued) inspections in the pressurizer compartment during power operation and analysis performed that shows an open hatch (7.5 ft2 bypass area) during a DBA does not impact the design pressure or temperature of the containment.

C.1 If the divider barrier seal is inoperable, 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> is allowed to restore the seal to OPERABLE status. The 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Completion Time is consistent with LCO 3.6.1, which requires that containment be restored to OPERABLE status within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.

D.1 and D.2 If divider barrier integrity cannot be restored to OPERABLE status within the required Completion Time, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-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 Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

SURVEILLANCE SR 3.6.14.1 REQUIREMENTS Verification, by visual inspection, that all personnel access doors and equipment hatches between the upper and lower containment compartments are closed provides assurance that divider barrier integrity is maintained prior to the reactor being taken from MODE 5 to MODE 4.

This SR is necessary because many of the doors and hatches may have been opened for maintenance during the shutdown.

SR 3.6.14.2 Verification, by visual inspection, that the personnel access door and equipment hatch seals, sealing surfaces, and alignments are acceptable provides assurance that divider barrier integrity is maintained. This Catawba Units 1 and 2 B 3.6.14-4 Revision No. 2

Divider Barrier Integrity B 3.6.14 BASES SURVEILLANCE REQUIREMENTS (continued) inspection cannot be made when the door or hatch is closed. Therefore, SR 3.6.14.2 is required for each door or hatch that has been opened, prior to the final closure. Some doors and hatches may not be opened for long periods of time. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.6.14.3 Verification, by visual inspection, after each opening of a personnel access door or equipment hatch that it has been closed makes the operator aware of the importance of closing it and thereby provides additional assurance that divider barrier integrity is maintained while in applicable MODES.

SR 3.6.14.4 Conducting periodic physical property tests on divider barrier seal test coupons provides assurance that the seal material has not degraded in the containment environment, including the effects of irradiation with the reactor at power. The required tests include a tensile strength test. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.6.14.5 Visual inspection of the seal around the perimeter provides assurance that the seal is properly secured in place. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

REFERENCES

1.

UFSAR, Section 6.2.

2.

10 CFR 50.36, Technical Specifications, (c)(2)(ii).

Catawba Units 1 and 2 B 3.6.14-5 Revision No. 2