ML081350257

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Revisions to Technical Specifications Bases Manual, Rev. 2 to Text 3.7.1, RHRSW System and UHS & Rev. 2 to 3.7.2, ESW System
ML081350257
Person / Time
Site: Susquehanna Talen Energy icon.png
Issue date: 05/05/2008
From: Gerlach R
Susquehanna
To: Gerlach R
Office of Nuclear Reactor Regulation
References
Download: ML081350257 (25)


Text

May.

05, 2008 Pagel of 1 MANUAL HARD COPY DISTRIBUTION DOCUMENT TRANSMITTAL 2008-23691 USER INFORMATION:

Name: GERLACH*ROSE M EMPL#:028401 CA#:0363 Address: NUCSA2 Phone#:

254-3194 TRANSMITTAL INFORMATION:

TO:

GERLACH*ROSE M 05/05/2008 LOCATION:

USNRC FROM:

NUCLEAR RECORDS DOCUMENT CONTROL CENTER (NUCSA-2)

THE FOLLOWING CHANGES HAVE OCCURRED TO THE HARDCOPY OR ELECTRONIC MANUAL ASSIGNED TO YOU.

HARDCOPY USERS MUST ENSURE THE DOCUMENTS PROVIDED MATCH THE INFORMATION ON THIS TRANSMITTAL.

WHEN REPLACING THIS MATERIAL IN YOUR HARDCOPY MANUAL, ENSURE THE UPDATE DOCUMENT ID IS THE SAME DOCUMENT ID YOU'RE REMOVING FROM YOUR MANUAL.

TOOLS SOM THE HUMAN PERFORMANCE TOOL BAG SHOULD BE UTILIZED TO ELIMINATE THE CHANCE OF RORS.

ATTENTION:

"REPLACE" directions do not affect the Table of Contents, Therefore no TOC will be issued with the updated material.

TSB2 -

TECHNICAL SPECIFICATIONS BASES UNIT 2 MANUAL REMOVE MANUAL TABLE OF CONTENTS DATE: 04/25/2008 ADD MANUAL TABLE OF CONTENTS DATE: 05/02/2008 CATEGORY:

DOCUMENTS TYPE:

TSB2 ID:

TEXT 3.7.1 ADD:

REV:

2 REMOVE:

REV:l CATEGORY:

ID:

TEXT REMOVE:

DOCUMENTS TYPE:

TSB2 3.7.2 REV: 1 PDD:

REV: 2 ANY DISCREPANCIES WITH THE MATERIAL PROVIDED, CONTACT DCS @ X3107 OR X3136 FOR ASSISTANCE.

UPDATES FOR HARDCOPY MANUALS WILL BE DISTRIBUTED WITHIN 3 DAYS IN AV~

pop1 2,

May.

05, 2008 Page 2 of 2 I

ACCORDANCE WITH DEPARTMENT PROCEDURES.

PLEASE MAKE ALL CHANGES AND ACKNOWLEDGE COMPLETE IN YOUR NIMS INBOX UPON COMPLETION OF UPDATES.

FOR ELECTRONIC MANUAL

USERS, ELECTRONICALLY REVIEW THE APPROPRIATE DOCUMENTS AND ACKNOWLEDGE COMPLETE IN YOUR NIMS INBOX.

SSES MA.NUAL~

Manual Name:

TSB2 Manual.Title: TECHNICAL SPECIFICATIONS BASES UNIT 2 MANUAL Table Of Contents Issue Date:

05/02/2008 Procedure Name Rev TEXT LOES 90

Title:

LIST OF EFFECTIVE SECTIONS Issue Date 04/23/2008 Change ID Change Number TEXT TOC

Title:

TABLE OF CONTENTS 13 04/23/2008 TEXT 2.1.1 3

Title:

SAFETY LIMITS (SLS) REACTOR 10/04/2007 CORE SLS TEXT 2.1.2

Title:

SAFETY LIMITS (SLS) i 10/0,4/2007\\i

.REACTOR COOLANT SYSTEM (RCS)

PRESSURE SL TEXT 3.0 2

10/1-2/2006,

Title:

LIMITING CONDITION FOR OPERATION-(LCO). APPLICABILITY TEXT 3. 1. 1

Title:

REACTIVITY TEXT 3.1.2

Title:

REACTIVITY TEXT 3.1.3

Title:

REACTIVITY TEXT 3.1.4

Title:

REACTIVITY TEXT 3.1.5

Title:

REACTIVITY TEXT 3.1.6

Title:

REACTIVITY CONTROL -SYSTEMS SM>03/24/2005 SHUTDOWN MARGIN (SDM) 0 11/18/2002 CONTROL SYSTEMS REACTIVITY ANOMALIES

/

/

1 CONTROL SYSTEMS 3'

CONTROL SYSTEMS 07/06/2005 CONTROL ROD 09/29/2006 CONTROL ROD OPERABILITY SCRAM TIMES 1

07/06/2005 CONTROL SYSTEMS CONTROL ROD SCRAM ACCUMULATORS 2

03/24/2005 CONTROL SYSTEMS ROD PATTERN CONTROL Pagel of a Report 'Date: 05/02/08 Page I of 8

Report-Date: 05/02/08

SSES-MANUAL Manual Name:

TSB2 Manual

Title:

TECHNICAL SPECIFICATIONS BASES UNIT. 2 MANUAL TEXT 3.1.7 3

10/04/2007

Title:

REACTIVITY CONTROL SYSTEMS STANDBY LIQUID CONTROL (SLC)

SYSTEM.

TEXT 3.1.8 2

10/04/2007

Title:

REACTIVITY CONTROL SYSTEMS SCRAM DISCHARGE VOLUME: (SDV)

VENT AND DRAIN VALVES TEXT 3.2.1

Title:

POWER DISTRIBUTION.

TEXT 3.2.2

Title:

POWER DISTRIBUTION 3

04/09/2007 LIMITS AVERAGE PLANAR LINEAR HEAT GENERATION RATE (APLHGR).

2 04/.03/2007 LIMITS MINIMUM CRITICAL POWER RATIO (MCPR)

TEXT 3.2.3 1

10/.04/2007

Title:

POWER DISTR:IBUTION LIMITS LINEAR-HEAT GENERATION RATE LHGR TEXT 3.3.1.1

Title:

INSTRUMENTATION 3

04/09/2007 REACTOR.PROTECTION SYSTEM (RPS.)

INSTRUMENTATION TEXT 3.3.1.2

.1 04/09/2007

Title:

INSTRUMENTATION SOURCE RANGE MONITOR (SRM)

INSTRUMENTATION TEXT 3.3.2.1 2

04/09/2007

Title:

INSTRUMENTATION CONTROL ROD BLOCK INSTRUMENTATION TEXT 3.3.2.2 0

11/18/2002

Title:

INSTRUMENTATION FEEDWATER -

MAIN TURBINE HIGH WATER LEVEL TRIP INSTRUMENTATION TEXT 3.3.3.1 6

12/17/2007

Title:

INSTRUMENTATION POST ACCIDENT MONITORING (PAM)

INSTRUMENTATION TEXT 3.3.3.2 1

04/18/2005

Title:

INSTRUMENTATION REMOTE SHUTDOWN SYSTEM TEXT 3.3.4.1 0

11/18/2002

Title:

INSTRUMENTATION END OF CYCLE RECIRCULATION PUMP TRIP (EOC-RPT)

INSTRUMENTATION W

e 2 of 8

!..Report Date: 05/02/08 Pag

..... SSES MANUAL Manual Name:

TSB2 Manual

Title:

TECHNICAL SPECIFICATIONS BASES UNIT 2 MANUAL TEXT 3.3.4.2 0

11/18/2002

Title:

INSTRUMENTATION ANTICIPATED TRANSIENT WITHOUT SCRAM RECIRCULATION PUMP TRIP (ATWS-RPT)

INSTRUMENTATION TEXT 3.3.5.1 3

07/06/2005

Title:

INSTRUMENTATION EMERGENCY CORE COOLING SYSTEM. (ECCS)

INSTRUMENTATION TEXT 3.3.5.2 0

11/18/2002

Title:

INSTRUMENTATION REACTOR CORE ISOLATION COOLING (RCIC)

SYSTEM INSTRUMENTATION TEXT 3.3.6.1

Title:

INSTRUMENTATION TEXT 3.3.6.2

Title:

INSTRUMENTATION TEXT 3.3.7.1

Title:

INSTRUMENTATION INSTRUMENTATION TEXT 3.3.8.1

Title:

INSTRUMENTATION 3

10/04/2007 PRIMARY CONTAINMENT ISOLATION INSTRUMENTATION 2

10/04-/2007, SECONDARY CONTAINMENT ISOLATION INSTRUMENTATION 1

10/04/2007 CONTROL ROOM EMERGENCY-OUTSIDE AIR SUPPLY (CREOAS)

SYSTEM 3

12/17/2007 LOSS OF, POWER (LOP)

INSTRUMENTATION TEXT 3.3.8.2 0

11/18/2002

Title:

INSTRUMENTATION REACTOR PROTECTION SYSTEM (RPS)

ELECTRIC POWER MONITORING TEXT 3.4.1 3

04/09/2007

Title:

'REACTOR COOLANT SYSTEM (RCS)

RECIRCULATION LOOPS OPERATING TEXT 3.4.2 0

11/18/2002

Title:

REACTOR COOLANT SYSTEM (RCS)

JET PUMPS TEXT 3.4.3 1

01/16/2006

Title:

REACTOR COOLANT SYSTEM (RCS)

SAFETY/RELIEF VALVES (S/RVS)

TEXT 3.4.4

Title:

REACTOR COOLANT 0

11/18/2002 SYSTEM (RCS) RCS OPERATIONAL LEAKAGE Page 3 df 8

Report Date: 05/02/08 Page 3 of -_8 Report Date: 05/02/08

SSES MANUAL, Manual Name:

TSB2 Manual

Title:

TECHNICAL SPECIFICATIONS BASES UNIT 2 MANUAL TEXT 3.4.5

Title:

REACTOR COOLANT 2

04/19/2007 SYSTEM (RCS)

RCS PRESSURE ISOLATION-VALVE (PIV).LEAKAGE TEXT 3.4.6 1

04/18/2005

Title:

REACTOR COOLANT SYSTEM (RCS)

RCS LEAKAGE DETECTION INSTRUMENTATION TEXT 3.4.7

Title:

REACTOR COOLANT TEXT 3.4.8

Title:

REACTOR COOLANT HOT SHUTDOWN TEXT 3.4.9

Title:

REACTOR COOLANT COLD SHUTDOWN 2

10/04/2007 SYSTEM. (RCS)

RCS SPECIFIC-ACTIVITY 1

,04/18/2005 SYSTEM (RCS)

RESIDUAL HEAT REMOVAL -(RHR)

SHUTDOWN COOLING SYSTEM 0

.-11/18/2002 SYSTEM. (RCS)

RESIDUAL HEAT REMOVAL (RHR)

SHUTDOWN COOLING -SYSTEM TEXT 3.4.10 2

05/10/2006

Title:

REACTOR COOLANT SYSTEM-(RCS)

RCS PRESSURE AND TEMPERATURE (P/T.,) LIMITS TEXT 3.4.11 0

11/18/2002

Title:

REACTOR COOLANT SYSTEM (RCS)

REACTOR STEAM DOME PRESSURE TEXT 3.5.1 3

01/16/2006

Title:

EMERGENCY CORE COOLING SYSTEMS (ECCS)

AND REACTOR:CORE ISOLATION COOLING (RCIC)

SYSTEM ECCS OPERATING TEXT 3.5.2 0

11/18/2002

Title:

EMERGENCY CORE COOLING SYSTEMS (ECCS)

AND REACTOR CORE ISOLATION. COOLING-(RCIC)

SYSTEM ECCS -

SHUTDOWN TEXT 3.5.3 1

04/18/2005

Title:

EMERGENCY CORE COOLING SYSTEMS (ECCS)

AND REACTOR CORE ISOLATION COOLING (RCIC)

SYSTEM RCIC SYSTEM TEXT 3.6.1.1 2

10/04/2007

Title:

CONTAINMENT SYSTEMS PRIMARY CONTAINMENT TEXT 3.6.1.2 0

11/18/2002

Title:

CONTAINMENT SYSTEMS PRIMARY CONTAINMENT AIR LOCK Page 4 of 8 Report Date: 05/02/08

,Page 4 of

-8 Repo.rt Date: 05/02/08

SSES MANUAL Manual Name:

TSB2 Manual

Title:

TECHNICAL SPECIFICATIONS' BASES -UNIT 2 MANUAL TEXT 3.6.1.3

Title:

CONTAINMENT TEXT 3.6.1.4

Title:

CONTAINMENT TEXT 3.6.1.5

Title:

CONTAINMENT TEXT 3.6.1.6

Title:

CONTAINMENT TEXT 3.6.2.1

Title:

CONTAiNMENT TEXT 3.6.2:2

Title:

CONTAINMENT TEXT 3.6.2.3

Title:

CONTAINMENT TEXT 3.6.2.4

Title:

CONTAINMENT TEXT 3.6.3.1

Title:

CONTAINMENT TEXT 3.6.3.2

Title:

CONTAINMENT TEXT 3.6.3.3

Title:

CONTAINMENT TEXT 3.6.4.1

Title:

CONTAINMENT 8

01/23/2008 SYSTEMS PRIMARY CONTAINMENT ISOLATION VALVES (PCIVS) 0

.11/18/2002 SYSTEMS CONTAINMENT PRESSURE 1

10/05/2005 SYSTEMS DRYWELL AIR TEMPERATURE 0

11/18/2002 SYSTEMS SUPPRESSION CHAMBER-TO-DRYWELL VACUUM BREAKERS 2

12/17/2007 SYSTEMS SUPPRESSION. POOL AVERAGE TEMPERATURE 0

11/18/2002 SYSTEMS SUPPRESSION POOL WATER LEVEL 1

01/16/2006 SYSTEMS RESIDUAL HEAT REMOVAL (RHR)

SUPPRESSION POOL COOLING 0

11/18/2002 SYSTEMS RESIDUAL HEAT REMOVAL (RHR)

SUPPRESSION POOL SPRAY 2

06/13/2006 SYSTEMS PRIMARY CONTAINMENT HYDROGEN RECOMBINERS 1

04/18/2005 SYSTEMS DRYWELL AIR FLOW SYSTEM 0

11/18/2002 SYSTEMS PRIMARY CONTAINMENT OXYGEN CONCENTRATION 7

10/04/2007 SYSTEMS SECONDARY CONTAINMENT Page 5 of *8 Report Date: 05/02/08 Page 5 of

-8 Report Date: 05/02/08

SSES.

MANTAL Manual Name:

TSB2 Manual

Title:

TECHNICAL SPECIFICATIONS BASES-UNIT 2 MANUAL TEXT 3.6.4.2 2

01/03/2005

Title:

CONTAINMENT SYSTEMS SECONDARY CONTAINMENT ISOLATION VALVES (SCIVS:)

TEXT 3.6.4.3 4

09/21/2006

Title:

CONTAINMENT SYSTEMS STANDBY GAS TREATMENT (SGT)

SYSTEM TEXT 3.7.1

Title:

PLANT SYSTEMS ULTIMATE HEAT 2

.,05/02/2008 RESIDUAL HEAT REMOVAL SERVICE WATER (RHRSW)

SYSTEM AND THE SINK(UHS)

TEXT 3.7.2

Title:

PLANT TEXT 3.7.3

Title:

PLANT TEXT 3.7.4

Title:

PLANT TEXT 3.7.5

Title:

PLANT TEXT 3.7.6

Title:

PLANT TEXT 3.7.7

Title:

PLANT TEXT 3.8.1 2

05/02/2008 SYSTEMS EMERGENCY SERVICE WATER (ESW)

SYSTEM 0

11/18/2002 SYSTEMS CONTROL ROOM EMERGENCY OUTSIDE AIR SUPPLY (CREOAS)

SYSTEM' 0

11/18/2002 SYSTEMS CONTROL ROOM FLOOR COOLING SYSTEM 1

10/04/2007 SYSTEMS MAIN CONDENSER OFFGAS 1

,01/i7/2005 SYSTEMS MAIN TURBINE BYPASS SYSTEM 1

10/04/2007 SYSTEMS SPENT FUEL STORAGE POOL WATER LEVEL, 7

04/23/2008

Title:

ELECTRICAL POWER-SYSTEMS AC SOURCES -

OPERATING TEXT 3.8.2 0

11/18/2002

Title:

ELECTRICAL POWER SYSTEMS AC SOURCES -

SHUTDOWN TEXT 3.8.3 1

04/23/2008

Title:

ELECTRICAL POWER SYSTEMS DIESEL FUEL OIL LUBE OIL AND STARTING AIR Page6 of 8 Report Date: 05/02/08 Page 6 of

.8 Report Date: 05/02/08

'SSES MANTJAL Manual Name

TSB2 Manual

Title:

TECHNICAL SPECIFICATIONS BASES UNIT 2 MANUAL TEXT 3. 8.4

Title:

ELECTRICAL TEXT 3.8.5

Title:

ELECTRICAL TEXT 3.8.6 Title-ELECTRICAL TEXT 3.8.7

Title:

ELECTRICAL 2

.12/14/2006 POWER SYSTEMS DC SOURCES -

OPERATING 1

1-2/14/2006 POWER SYSTEMS DC SOURCES -

SHUTDOWN 1

12/14/2006 POWER SYSTEMS BATTERY CELL PARAMETERS 3

03/31/2006 POWER SYSTEMS DISTRIBUTION SYSTEMS OPERATING TEXT 3. 8.8

Title:

ELECTRICAL TEXT-3.9.1

Title:

REFUELING TEXT 3.9.2

Title:

REFUELING TEXT 3.9.3

Title:

REFUELING TEXT 3.9.4

Title:

REFUELING TEXT 3.9.5

Title:

REFUELING TEXT 3.9.6

Title:

REFUELING TEXT 3.9.7

Title:

REFUELING 0

11/18/2002 POWER SYSTEMS DISTRIBUTION SYSTEMS SHUTDOWN 0

11/1,8/2002 OPERATIONS REFUELING EQUIPMENT INTERLOCKS 0

11/18/2002 OPERATIONS REFUEL POSITION ONE-ROD-OUT INTERLOCK 0

11/18/2002 OPERATIONS CONTROL ROD POSITION 0

11/18/2002 OPERATIONS CONTROL ROD POSITION INDICATION 0

11/18/2002 OPERATIONS CONTROL ROD OPERABILITY -

REFUELING 1

10/04/2007 OPERATIONS REACTOR PRESSURE VESSEL (RPV)

WATER LEVEL 0

11/18/2002 OPERATIONS RESIDUAL HEAT REMOVAL (RHR)

HIGH WATER LEVEL Page7 of 8 Report Date: 05/02/08 Page 7 of

-8 Report Date: 05/02/08

SSES MANUAL, Manual Name:

TSB2 Manual

Title:

TECHNICAL SPECIFICATIONS BASES UNIT 2 MANUAL TEXT 3.9.8 0

11/18/2002

.Title:'

REFUELING OPERATIONS RESIDUAL HEAT REMOVAL (RHR)

LOW WATER LEVEL TEXT 3.10.1 1

01V231/2008,

Title:

SPECIAL OPERATIONS INSERVICE LEAK AND HYDROSTATIC TESTING OPERATION TEXT 3.10.2 0

11/18/2002

Title:

SPECIAL OPERATIONS REACTOR MODE SWITCH INTERLOCK TESTING TEXT 3.10.3 0

11/18/2002

Title:

SPECIAL OPERATIONS SINGLE CONTROL-ROD WITHDRAWAL

-. HOT SHUTDOWN TEXT 3.10.4

Title:

SPECIAL OPERATIONS_.

TEXT -.10.5

Title:

SPECIAL OPERATIONS TEXT 3.10.6

Title:

SPECIAL OPERATIONS TEXT 3.10.7

Title:

SPECIAL OPERATIONS.

TEXT 3.10.8

Title:

SPECIAL OPERATIONS 0

11/18/2002 SINGLE CONTROL ROD WITHDRAWAL COLD SHUTDOWN 0

11/18:/202 SINGLE CONTROL ROD DRIVE (CRDY REMOVAL REFUELING 0

11/18/2002 MULTIPLE CONTROLROD WITHDRAWAL -REFUELING 1

03/24/2005 CONTROL ROD TESTING. -

OPERATING 2

04/09/2007 SHUTDOWN mARGIN (SDM)

TEST REFUELING Page8 of 8

Report Date: 05/02/08 Page 8 of

.8 Report Date: 05/02/08

PPL Rev. 2 RHRSW System and UHS B 3.7.1 B 3.7 PLANT SYSTEMS B 3.7.1 Residual Heat Removal Service Water (RHRSW) System and the Ultimate Heat Sink (UHS)

BASES BACKGROUND The RHRSW System is designed to provide cooling water for the Residual Heat Removal (RHR) System heat exchangers, required for a safe reactor shutdown following a Design Basis Accident (DBA) or transient. The RHRSW System is operated whenever the RHR heat exchangers are required to operate in the shutdown cooling mode or in the suppression pool cooling or spray mode of the RHR System.

The RHRSW System consists of two independent and redundant subsystems. Each subsystem is made up of a header, one pump, a suction source, valves, piping, heat exchanger, and associated instrumentation. Either of the two subsystems is capable of providing the required cooling capacity to maintain safe shutdown conditions. The two subsystems are separated so that failure of one subsystem will not affect the OPERABILITY of the other subsystem. One Unit I RHRSW

-subsystem and the associated (same division) Unit 2 RHRSW subsystem.

constitute a single RHRSW loop. The two RHRSW pumps in a loop can each, independently, be aligned to either Unit's heat exchanger. The RHRSW System is designed with sufficient redundancy so that no single.

active component failure can prevent it from achieving its design function.

The RHRSW System is described in the FSAR, Section 9.2.6, Reference 1.

Cooling water is pumped by the RHRSW pumps from the UHS through the tube side of the RHR heat exchangers. After removing heat from the RHRSW heat exchanger, the water is discharged to the spray pond (UHS) by way of the UHS return loops. The UHS return loops direct the return flow to a network of sprays that dissipate the heat to the atmosphere or directly to the UHS via a bypass header.

The system is initiated manually from the control room except for the spray array bypass manual valves that are operated locally in the event of a failure of the spray array bypass valves. The system can be started any time the LOCA signal is manually overridden or clears.

(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-1 Revision 3

PPL Rev. 2 RHRSW System and UHS B 3.7.1 BASES BACKGROUND (continued)

The ultimate heat sink (UHS) system is composed of approximately 3,300,000 cubic foot spray pond and associated piping and spray risers.

Each UHS return loop contains a bypass line, a large spray array and a small spray array. The purpose of the UHS is to provide both a suction source of water and a return path for the RHRSW and ESW systems.

The function of the UHS is to provide water to the RHRSW and ESW systems at a temperature less than the 970F design temperature of the RHRSW and ESW systems. UHS temperature is maintained less than the design temperature by introducing the hot return fluid from the RHRSW and ESW systems into the spray loops and relying on spray cooling to maintain temperature. The UHS is designed to supply the RHRSW and ESW systems with all the cooling capacity required during a combination LOCA/LOOP for thirty days without fluid addition. The UHS is described in the FSAR, Section 9.2.7 (Reference 1).

APPLICABLE SAFETY ANALYSES The RHRSW System removes heat from the suppression pool to limit the suppression pool temperature and primary containment pressure following a LOCA. This ensures that the primary containment can perform its

-function of limiting. the release of radioactive materials to the environment following a LOCA. The ability of the RHRSW System to support long term cooling of the reactor or primary containment is discussed in the FSAR, Chapters 6 and 15 (Refs. 2 and 3, respectively). These analyses explicitly "

assume that the RHRSW System will provide adequate cooling support to the equipment required for safe.shutdown. These analyses include the evaluation of the long term primary containment response after a design-basis LOCA.

The safety analyses for long term cooling were performed for various RHRSW and UHS configurations combinations of RHR System failures.

As discussed in the FSAR, Section 6.2.2 (Ref. 2) for these analyses, manual initiation of the OPERABLE RHRSW subsystem and the associated RHR System is required. The maximum suppression chamber water temperature and pressure are analyzed to be below the design temperature of 220°F and maximum allowable pressure of 53 psig.

(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-2 Revision 4

PPL Rev. 2 RHRSW System and UHS B 3.7.1 BASES APPLICABLE The UHS design takes into account the cooling efficiency of the spray SAFETY arrays and the evaporation losses during design basis environmental ANALYSES conditions. The spray array bypass header provides the flow path for the (continued)

ESW and RHRSW system to keep the spray array headers from freezing.

The small and/or large spray arrays are placed in service to dissipate heat returning from the plant. The UHS return header is comprised of the spray array bypass header, the large spray array, and the small spray array.

The spray array bypass header is capable of passing full flow from the RHRSW and ESW systems in each loop. The large spray array is capable of passing full flow from the RHRSW and ESW systems in each loop. The small spray array supports heat dissipation when low system flows are required.

The RHRSW System, together with the UHS, satisfy Criterion 3 of the NRC Policy Statement. (Ref. 4)

LCO Two RHRSW subsystems are required to be OPERABLE to provide the

- required redundancy to ensure that the system functions to remove post accident heat loads, assuming the worst case single active failure occurs' coincidentwith-the loss of offsite power.

An RHRSW subsystem is considered OPERABLE when:

a. One pump is OPERABLE; and
b. An OPERABLE flow path is capable of taking suction from the UHS and transferring the water to the RHR heat exchanger and returning it to the UHS at the assumed flow rate, and
c. An OPERABLE UHS.

The OPERABILITY of the UHS is based on having a minimum water level at the overflow weir of 678 feet 1 inch above mean sea level and a maximum water temperature of 850F; unless either unit is in MODE 3. If a unit enters MODE 3, the time of entrance into this condition determines the appropriate maximum ultimate heat sink fluid temperature. If the earliest unit to enter MODE 3 has been in that condition for less than twelve (12) hours, the peak temperature to maintain OPERABILITY of the ultimate heat sink remains at 85 0F. If either unit has been in MODE 3 for more than twelve (12) hours but less than twenty-four (24) hours, the OPERABILITY temperature of the ultimate heat sink becomes 87 0F. If either unit has been in MODE 3 for twenty-four (24) hours or more, the OPERABILITY temperature of the ultimate heat sink becomes 880F.

(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-3 Revision 3

PPL Rev. 2 RHRSW System and UHS B 3.7.1 BASES LCO In addition, the OPERABILITY of the UHS is based on having sufficient (continued) spray capacity in the UHS return loops. Sufficient spray capacity is defined as one large and one small spray array in one loop.

This OPERABILITYdefinition is supported by analysis and evaluations performed in accordance with the guidance given in Regulatory Guide

  • 1.27.

APPLICABILITY In MODES 1, 2, and 3, the RHRSW System and the UHS are required to be OPERABLE to support the OPERABILITY of the RHR System for primary containment cooling (LCO 3.6.2.3, "Residual Heat Removal (RHR)

Suppression Pool Cooling," and LCO 3.6.2.4, "Residual Heat Removal (RHR) Suppression Pool Spray") and decay heat removal (LCO 3.4.8, "Residual Heat Removal (RHR) Shutdown Cooling System-Hot Shutdown"). The Applicability is therefore consistent with the requirements of these systems.

In MODES 4 and 5, the OPERABILITY requirements of the RHRSW System are deterrnined by the RHR shutdown cooling subsystem(s) it supports (LCO 3.4.9, "Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown"; LCO 319.7, "Residual Heat' Removal (RHR) -

High Water Level"; and LCO 3.9.8, "Residual Heat Removal (RHR) - Low Water Level").

In MODES 4 and 5, the OPERABILITY requirements of the UHS is determined by the systems it supports.

ACTIONS The ACTIONS are modified by a Note indicating that the applicable Conditions of LCO 3.4.8, be entered and Required Actions taken if the inoperable RHRSW subsystem results in inoperable RHR shutdown cooling (SDC) (i.e., both the Unit 1 and Unit 2 RHRSW pumps in a loop are inoperable resulting in the associated RHR SDC system being inoperable). This is an exception to LCO 3.0.6 because the Required Actions of LCO 3.7.1 do not adequately compensate for the loss of RHR SDC Function (LCO 3.4.8).

Condition A is modified by a separate note to allow separate Condition entry for each valve. This is acceptable since the Required Action for this Condition provide appropriate compensatory actions.

(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-4 Revision 3

PPL Rev. 2 RHRSW System and UHS B 3.7.1 BASES ACTIONS (continued)

A. 1 With one spray loop bypass valve not capable of being closed on demand, the associated Unit 1 and Unit 2 RHRSW subsystems cannot use the spray cooling function of the affected UHS return loop. As a result, the associated RHRSW subsystem must be declared inoperable.

With one spray loop bypass valve not capable of being opened on demand, a return flow path is not available. As a result, the associated RHRSW subsystems must be declared inoperable.

With one spray array bypass manual valve not capable of being closed, the associated Unit 1 and Unit 2 RHRSW subsystems cannot use the spray cooling function of the affected UHS return path if the spray array bypass valve fails to close. As a result, the associated RHRSW subsystems must be declared inoperable.

With one spray array bypass manual valve not open, a return flow path is

-not available. As a result, the associated RHRSW subsystems must be declared inoperable.

With one large spray array valve not capable of being opened on demand, the associated Unit 1 and Unit 2 RHRSW subsystems cannot use the full required spray cooling. capability of the affected UHS return path. With one large spray array valve not capable of being closed on demand, the associated Unit 1 and Unit 2 RHRSW subsystems cannot use the small spray array when loop flows are low as the required spray nozzle pressure is not achievable for the small spray array. As a result, the associated RHRSW subsystems must be declared inoperable.

With one small spray array valve not capable of being opened on demand, the associated Unit 1 and Unit 2 RHRSW subsystems cannot use the spray cooling function of the affected UHS return path for low loop flow rates. For a single failure of the large spray array valve in the closed position, design bases LOCA/LOOP calculations assume that flow is reduced on the affected loop within 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> after the event to allow use of the small spray array. With one small spray array valve not capable of being closed on demand, the associated Unit.1 and Unit 2 RHRSW subsystems cannot use the large spray array for a flow path as the required nozzle pressure is not achievable for the large spray array. As a result, the associated RHRSW subsystems must be declared inoperable.

' O(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-5 Revision 3

PPL Rev. 2 RHRSW System and UHS B 3.7.1 BASES ACTIONS With any UHS return path valve listed in Tables 3.7.1-1, 3.7.1-2, or 3.7.1-3 (continued) inoperable, the UHS return path is no longer single failure proof.

For combinations of inoperable valves in the same loop, the UHS spray capacity needed to support the OPERABILITY of the associated Unit 1 and Unit 2 RHRSW subsystems is affected. As a result, the associated RHRSW subsystems must be declared inoperable.

The 8-hour completion time to establish the flow path provides sufficient time to open a path and de-energize the appropriate valve in the open position.

The 72-hour completion time is based on the fact that, although adequate UHS spray loop capability exists during this time period, both units are affected and an additional single failure results in a system configuration that will not meet design basis accident requirements.

If an additional RHRSW subsystem on either Unit is inoperable, cooling capacity less than the minimum required for response to a design basis

-event would exist. Therefore, an 8-hour Completion Time is appropriate.

The 8-hour Completion Time provides sufficient time to restore inoperable equipment and there is a low probability that a design basis event would "

occur during this period.

B.1 Required Action B.1 is intended to ensure that appropriate actions are taken if one Unit 2 RHRSW subsystem is inoperable. Although designated and operated as a unitized system, the associated Unit 1 subsystem is directly connected to a common header which can supply the associated RHR heat exchanger in either unit. The Unit 1 subsystems" are considered capable of supporting Unit 2 RHRSW subsystem when the Unit 1 subsystem is OPERABLE and can provide the assumed flow to the Unit 2 heat exchanger. A Completion time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, when one Unit 1 RHRSW subsystem is not capable of supporting the Unit 2 RHRSW subsystems, is allowed to restore the Unit 2 RHRSW subsystem to OPERABLE status. In this configuration, the remaining OPERABLE Unit 2 RHRSW subsystem is adequate to perform the RHRSW heat removal function. However, the overall reliability is reduced because a single failure in the OPERABLE RHRSW subsystem (continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-5a Revision 0

PPL Rev. 2 RHRSW System and UHS B 3.7.1 BASES ACTIONS B.1 (continued could result in loss of RHRSW function. The Completion Time is based on the redundant RHRSW capabilities. afforded by the OPERABLE subsystem and the low probability of an event occurring requiring RHRSW during this period.

With one RHRSW subsystem inoperable, and both of the Unit 1 RHRSW subsystems capable of supporting their respective Unit 2 RHRSW subsystems, the design basis cooling capacity for both units can still be maintained even considering a single active failure. However, the configuration does reduce the overall reliability of the RHRSW System.

Therefore, provided both of the Unit 1 subsystems remain capable of supporting their respective Unit 2 RHRSW subsystems, the inoperable RHRSW subsystem must be restored to OPERABLE status within 7 days.

The 7-day Completion Time is based on the remaining RHRSW System heat removal capability.

C.1 Required Action C.1 is intended to ensure that appropriate actions are taken if both Unit 2 RHRSW subsystems are inoperable. Although designated and operated as a unitized system, the associated Unit 1 subsystem is directly connected to a common header which can supply the associated RHR heat exchanger in either unit. With both Unit 2 RHRSW subsystems inoperable, the RHRSW system is still capable of-performing its intended design function. However, the loss of an additional RHRSW subsystem on Unit 1 results in the cooling capacity to be less than the minimum required for response to a design basis everit.

Therefore, the 8-hour Completion Time is appropriate. The 8-hour Completion Time for restoring one RHRSW subsystem to OPERABLE status, is based on the Completion Times provided for the RHR suppression pool spray function.

With both Unit 2 RHRSW subsystems inoperable, and both of the Unit 1 RHRSW subsystems capable of supporting their respective Unit 2 RHRSW subsystem, if no additional failures occur which impact the RHRSW System, the remaining OPERABLE Unit 1 subsystems and flow paths provide adequate heat removal capacity following a design basis LOCA. However, capability for this alignment is not assumed in long term containment response analysis and an additional single failure in the RHRSW System could reduce the system capacity below that assumed in the safety analysis.

(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-6 Revision 2

PPL Rev. 2 RHRSW System and UHS B 3.7.1 BASES ACTIONS C.1 (continued)

Therefore, continued operation is permitted only for a limited time. One inoperable subsystem is required to be restored to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Completion Time for restoring one inoperable RHRSW subsystem to OPERABLE status is based on the fact that the alternate loop is capable of providing the required cooling capability during this time period.

D.1 and D.2 If the RHRSW subsystems cannot be restored to OPERABLE status within the associated Completion Times, or the UHS is determined to be inoperable, the unit must be placed in a MODE in which the LCO does not apply. To achieve this status; the unit must be placed in at least MODE 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in MODE 4 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 unit conditions from full power conditions in an orderly manner and without challenging unit systems.

SURVEILLANCE SR 3.7.1.1 1 REQUIREMENTS This SR verifies the water level to be sufficient for the proper operation of the RHRSW pumps (net positive suction head and pump vortexing are considered in determining this limit). The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency is based on operating experience related to trending of the parameter variations during the applicable MODES.

SR 3.7.1.2 Verification of the UHS temperature, which is the arithmetical average of the UHS temperature near the surface, middle and bottom levels, ensures that the heat removal capability of the ESW and RHRSW Systems are within the assumptions of the DBA analysis. The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Frequency is based on operating experience related to trending of the parameter variations during the applicable MODES.

(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-6a Revision 2

PPL Rev. 2 RHRSW System and UHS B 3.7.1 BASES SURVEILLANCE REQUIREMENTS SR 3.7.1.3 (continued)

Verifying the correct alignment for each manual, power operated, and automatic valve in each RHRSW subsystem flow path provides assurance that the proper flow paths will exist for RHRSW operation. This SR does not apply to valves that are locked, sealed, or otherwise secured in position, since these valves are verified to be in the correct position prior to locking, sealing, or securing. A valve is also allowed to be in the nonaccident position, and yet considered in the correct position, provided it can be realigned to its accident position. This is acceptable because the RHRSW System is a manually initiated system.

This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

The 31-day Frequency is based on engineering judgment, is consistent with the procedural controls governing valve operation, and ensures correct valve positions.

SR 3.7.1.4 The UHS spray array bypass valves are required to actuate to the closed position for the UHS to perform its design function. These valves receive an automatic signal to open upon emergency service water (ESW) or residual heat removal service water (RHRSW) system pump start and are required to be operated from the control room or the remote shutdown panel. A spray bypass valve is considered to be inoperable when it cannot be closed on demand. Failure of the spray bypass valve to close on demand puts the UHS at risk to exceed its design temperature. The failure of the spray bypass valve to open on demand makes one return path unavailable, and therefore the associated RHRSW subsystems must be declared inoperable. This SR demonstrates that the valves will move to their required positions when required. The 92-day Test Frequency is based upon engineering judgement and operating/testing history that indicates this frequency gives adequate assurance that the valves will move to their required positions when required.

(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-6b Revision 1

PPL Rev. 2 RHRSW System and UHS B 3.7.1 BASES SURVEILLANCE REQUIREMENTS (continued) k SR 3.7.1.5 The UHS return header large spray array valves are required to open in order for the UHS to perform its design function. These valves are manually actuated from either the control room or the remote shutdown panel, under station operating procedure, when the RHRSW system is required to remove energy from the reactor vessel or suppression pool.

This SR demonstrates that the valves will move to their required positions when required. The 92-day Test Frequency is based upon engineering judgement and operating/testing history that indicates this frequency gives adequate assurance that the valves will move to their required positions when required.

SR 3.7.1.6 The small spray array valves HV-01224A2 and B2 are required to operate in order for the UHS to perform its design function. These valves are

-manually actuated from the control room or the remote shutdown panel, under station operating procedure, when the RHRSW system is required to remove energy from the reactor vessel-or suppression pool. This SR demonstrates that the-valves-will move to their required positions when required. The 92-day Test Frequency is based upon engineering judgment and operating/testing history that indicates this frequency gives adequate assurance that the valves will move to their required positions when required.

SR 3.7.1.7 The spray array bypass manual valves 012287A and B are required to operate in the event of a failure of the spray array bypass valves to close in order for the UHS to perform its design function.

REFERENCES

1. FSAR, Section 9.2.6.
2. FSAR, Chapter 6.
3. FSAR, Chapter 15.
4. Final Policy Statement on Technical Specifications Improvements, July 22, 1993 (58 FR 39132).

SUSQUEHANNA - UNIT 2 TS / B 3.7-6c Revision 1

PPL Rev. 2 ESW System B 3.7.2 B 3.7 B 3.7.2 PLANT SYSTEMS Emergency Service Water (ESW) System BASES BACKGROUND The ESW System is designed to provide cooling water for the removal of heat from equipment, such as the diesel generators (DGs), residual heat removal (RHR) pump coolers, and room coolers for Emergency Core Cooling System equipment, required for a safe reactor shutdown following a Design Basis Accident (DBA) or transient. Upon receipt of a loss of offsite power or loss of coolant accident (LOCA) signal, ESW pumps are automatically started after a time delay.

The ESW System consists of two independent and redundant subsystems. Each of the two ESW subsystems is made up of a header, two pumps, a suction source, valves, piping and associated instrumentation. The two subsystems are separated from each other so an active single failure in one subsystem will not affect the OPERABILITY of the other subsystem. A continuous supply of water is provided to ESW

-from the Service Water System for the keepfill system. This supply is not required for ESW operability.

Cooling water is pumped from the-Ultimate Heat Sink (UHS) by the ESW-..

pumps to the essential components through the two main headers. Afte-r removing heat from the comp6n.ents, the water is discharged to the spray pond (UHS) by way of a network of sprays that dissipate the heat to the.

atmosphere or directly to the UHS via a bypass header.

APPLICABLE SAFETY ANALYSES Sufficient water inventory is available for all ESW System post LOCA cooling requirements for a 30 day period with no additional makeup water-source available. The ability of the ESW System to support long term cooling is assumed in evaluations of the equipment required for safe reactor shutdown presented in the FSAR, Chapters 4 and 6 (Refs. 1 and 2, respectively).

The ability of the ESW System to provide adequate cooling to the identified safety equipment is an implicit assumption for the safety analyses evaluated in References 1 and 2. The ability to provide onsite emergency AC power is dependent on the ability of the ESW System to cool the DGs. The long term cooling capability of the RHR and core spray pumps is also dependent on the cooling provided by the ESW System.

The ESW System satisfies Criterion 3 of the NRC Policy Statement. (Ref.

3)

(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-7 Revision 3

PPL Rev. 2 ESW System B 3.7.2 BASES LCO The ESW subsystems are independent of each other to the degree that each has separate controls, power supplies, and the operation of one does not depend on the other. In the event of a DBA, one subsystem of ESW is required to provide the minimum heat removal capability assumed in the safety analysis for the system to which it supplies cooling water. To ensure this requirement is met, two subsystems of ESW must be OPERABLE. At least one subsystem will operate, if the worst single active failure occurs coincident with the loss of offsite power.

A subsystem is considered OPERABLE when it has two OPERABLE pumps, and an OPERABLE flow path capable of taking suction from the UHS and transferring the water to the appropriate equipment and returning flow to the UHS. If individual loads are isolated, the affected components may be rendered inoperable, but it does not necessarily affect the OPERABILITY of the ESW System. Because each ESW subsystem supplies all four required DGs, an ESW subsystem is considered OPERABLE if it supplies at least three of the four DGs

_provided no single DG does not have an ESW subsystem capable of supplying flow.

An adequate section source is not addressed in this LCO since the minimum net positive suction head of the ESW pumps is bounded by the" Residual Heat Removal Service Water System requirements-(LCO 3.7.1, "Residual -Heat Removal System and Ultimate Heat Sink (UHS)").

The ESW return loop requirement, in terms of operable UHS return paths or UHS spray capacity, is also not addressed in this LCO. UHS operability, in terms of the return loop and spray capacity is addressed in the RHRSW/ UHS Technical Specification (LCO 3.7.1, "Residual Heat Removal Service Water System and Ultimate Heat Sink (UHS)).

APPLICABILITY In MODES 1, 2, and 3, the ESW System is required to be OPERABLE to support OPERABILITY of the equipment serviced by the ESW System.

Therefore, the ESW System is required to be OPERABLE in these MODES.

In MODES 4 and 5, the OPERABILITY requirements of the ESW System is determined by the systems it supports.

(continued)

SUSQUEHANNA - UNIT 2 TS / B 3.7-8 Revision 2

PPL Rev. 2 ESW System B 3.7.2 BASES (continued)

ACTIONS The ACTIONS are modified by a Note indicating that the applicable Conditions of LCO 3.8.1, be entered and Required Actions taken if the inoperable ESW subsystem results in inoperable DGs (i.e., the supply from both subsystems of ESW is secured to the same DG). This is an exception to LCO 3.0.6 because the Required Actions of LCO 3.7.2 do not adequately compensate for the loss of a DG (LCO 3.8.1) due to loss of ESW flow.

A.1 With one ESW pump inoperable in each subsystem, both inoperable pumps must be restored to OPERABLE status within 7 days. With the unit in this condition, the remaining OPERABLE ESW pumps are adequate to perform the ESW heat removal function; however, the overall reliability is reduced because a single failure could result in loss of ESW function. The 7 day Completion Time is based on the remaining ESW heat removal capability and the low probability of an event occurring during this time period.

B.1 With one or both ESW subsystems not capable of supplying ESW flow to two or mole DGs, the capability to supply ESW to at least three DGs from each ESW subsystem must be restored within 7 days. With the units in this condition, the remaining ESW flow to DGs is adequate to maintain the full capability of all DGs; however, the overall reliability is reduced because a single failure could result in loss of the multiple DGs. The 7 day Completion Time is based on the fact that all DGs remain capable of -

responding to an event occurring during this time period.

C.1 With one ESW subsystem inoperable for reasons other than Condition B, the ESW subsystem must be restored to OPERABLE status within 7 days.

With the unit in this condition, the remaining OPERABLE ESW subsystem is adequate to perform the heat removal function. However, the overall reliability is reduced because a single failure in the OPERABLE ESW subsystem could result in loss of ESW function.

(continued)

SUSQUEHANNA-UNIT 2 B 3.7-9 Revision 0

PPL Rev. 2 ESW System B 3.7.2 BASES ACTIONS C.1 (continued)

The 7 day Completion Time is based on the redundant ESW System capabilities afforded by the OPERABLE subsystem, the low probability of an accident occurring during this time period, and is consistent with the allowed Completion Time for restoring an inoperable Core Spray Loop, LPCI Pumps and Control Structure Chiller.

D.1 and D.2 If the ESW subsystem cannot be restored to OPERABLE status within the associated Completion Time, or both ESW subsystems are inoperable for reasons other than Condition A and B (i.e., three ESW pumps inoperable),

the unit must be placed in a MODE in which the LCO does not apply. To achieve this status, the unit must be placed in at least MODE 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in MODE 4 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 unit conditions from full power conditions in an orderly manner and without challenging unit systems.

SURVEILLANCE SR 3.7.2.1 REQUIREMENTS Verifying the correct alignment for each manual, power operated, and automatic valve in each ESW subsystem flow path provides assurance that the proper flow paths will exist for ESW operation. This SR does not apply to valves that are locked, sealed, or otherwise secured in position, since these valves were verified to be in the correct position prior to locking, sealing, or securing. A valve is also allowed to be in the nonaccident position, and yet considered in the correct position, provided it can be automatically realigned to its accident position within the required time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

This SR is modified by a Note indicating that isolation of the ESW System to components or systems may render those (continued)

SUSQUEHANNA - UNIT 2 B 3.7-10 Revision 0

PPL Rev. 2 ESW System B 3.7.2 BASES SURVEILLANCE REQUIREMENTS SR 3.7.2.1 (continued) components or systems inoperable, but does not necessarily affect the OPERABILITY of the ESW System. As such, when all ESW pumps, valves, and piping are OPERABLE, but a branch connection off the main header is isolated, the ESW System is still OPERABLE.

The 31 day Frequency is based on engineering judgment, is consistent with the procedural controls governing valve operation, and ensures correct valve positions.

SR 3.7.2.2 This SR verifies that the automatic valves of the ESW System will automatically switch to the safety or emergency position to provide cooling water exclusively to the safety related equipment during an accident event. This is demonstrated by the use of an actual or simulated initiation signal. This SR also verifies the automatic start capability of the ESW pumps -in each subsystem.

Operating experience has shown that these components usually pass the SR when performed at the 24 month Frequency. Therefore, this Frequency is concluded to be acceptable from a reliability standpoint.

REFERENCES

1. FSAR, Chapter 4.
2. FSAR, Chapter 6.
3. Final Policy Statement on Technical Specifications Improvements, July 22, 1993 (58 FR 39132)

SUSQUEHANNA - UNIT 2 B 3.7-11 Revision 0