Text

Supplement to Response to Second Request for Additional Information on License Amendment Request for Adoption of Technical Specification Task Force (TSTF)-425, Revision 3
	ML15363A239
Person / Time
Site:	Columbia
Issue date:	12/28/2015
From:	Hettel W; Energy Northwest
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	GO2-15-173
	Download: ML15363A239 (45)
	v • d • e

W. Grover Hettel Vice President, Operations P.O. Box 968, Mail Drop PE23 Richland, WA 99352-0968 Ph. 509-377-2425 F. 509-377-4674 wghettel@energy-northwest.com December 28, 2015 GO2-15-173 10 CFR 50.90 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001

Subject:

COLUMBIA GENERATING STATION, DOCKET NO. 50-397 SUPPLEMENT TO RESPONSE TO SECOND REQUEST FOR ADDITIONAL INFORMATION ON LICENSE AMENDMENT REQUEST FOR ADOPTION OF TECHNICAL SPECIFICATION TASK FORCE (TSTF)-425, REVISION 3

References:

1. Letter, GO2-15-007, dated March 17, 2015, WG Hettel (Energy Northwest) to NRC, License Amendment Request for Adoption of Technical Specification Task Force Traveler (TSTF)-425, Revision 3

2. Letter, GO2-15-152, dated November 17, 2015, WG Hettel (Energy Northwest) to NRC, Response to Second Request for Additional Information on License Amendment Request for Adoption of Technical Specification Task Force (TSTF)-425, Revision 3

3. Email, dated December 7, 2015, Balwant Singal (NRC) to Lisa Williams (Energy Northwest), FW: List of Amendments not Incorporated in Markup/Clean TS pages for Columbia TSTF-425 Rev 3 LAR

Dear Sir or Madam:

In Reference 1, Energy Northwest submitted a license amendment request (LAR) to adopt TSTF-425, Revision 3. In Reference 2, Energy Northwest submitted responses to Nuclear Regulatory Commission (NRC) requests for additional information (RAIs),

which included a number of revisions to the proposed Technical Specification (TS) changes in Reference 1.

G02-15-173 Page 2 of 2 Via Reference 3 and subsequent phone call, the NRC requested revised markups and clean pages for the proposed Technical Specification (TS) changes submitted in References 1 and 2 to reflect TS changes approved in Amendments 229-235 and also those to be approved in Amendment 236, which is a license amendment to adopt TSTF-423 (End States). The request also included a noted error on TS page 3.3.4.1-3 and an update to the TS Bases related to Surveillance Requirement (SR) 3.6.1 .3.8. details the impacts of the aforementioned TS Amendments on the proposed TS changes previously submitted in References 1 and 2. Attachment 2 provides revised TS markups as described in Attachment 1. Attachment 3 provides the TS clean pages. Attachment 4 provides a revised TS Bases markup for SR 3.6.1.3.8 for information only as discussed in the subsequent phone call.

After benchmarking other nuclear power plants on the implementation activities for TSTF-425, Energy Northwest requests to change the implementation timeframe from 120 days to 180 days after receiving approval.

There are no new commitments being made to the NRC by this letter.

If there are any questions or if additional information is needed, please contact Ms. L. L.

Williams, Licensing Supervisor, at 509-377-8148.

I declare under penalty of perjury that the foregoing is true and correct. Executed this

~ dayof ~ ,20~.

Respectfully, W. G. Hettel Vice President, Operations Attachments: As stated.

cc: NRC Region IV Administrator NRC NRA Project Manager NRC Sr. Resident Inspector - 988C CD Sonoda - BPA 1399 (email)

WA Horin - Winston & Strawn (email)

RR Cowley-WDOH (email)

EFSEC (email)

GO2-15-173 Page 1 of 2 See list below for the impacts to the proposed Technical Specification (TS) changes in References 1 and 2 from changes approved in Amendments 229-235 and also those to be approved in Amendment 236, which is a license amendment to adopt TSTF-423 (End States):

1. Amendment 229 Amendment 229 changed TS Surveillance Requirement (SR) 3.5.1.4 and TS SR 3.5.2.5. Revised Markup and Clean TS pages incorporating the approved change are provided in Attachments 2 and 3, respectively.

2. Amendment 230 Amendment 230 changed the allowed Completion Time for Condition A for TS 3.5.1, TS 3.6.1.5, and TS 3.6.2.3. This change revised the pagination of these Specifications. As such, revised Markup and Clean TS pages are provided in Attachments 2 and 3, respectively.

3. Amendment 231 - no impact to any of the proposed changes previously submitted in References 1 and 2.

4. Amendment 232 Amendment 232 affected TS Table 3.3.1.1-1. Previously, in Reference 2, markups to TS 3.3.1.1 were submitted that rolled TS Table 3.3.1.1-1 onto different pages.

Due to the delay in implementation of Amendment 232, which was approved by Amendment 235, this page rolling is not desired. Therefore, revised Clean TS pages are provided in Attachment 3 such that the pagination of TS Table 3.3.1.1-1 is no longer affected. Additionally, only pages with Applicability of After Implementation of PRNM Upgrade are included since the Prior to Implementation of PRNM Upgrade are no longer applicable.

5. Amendment 233 Amendment 233 changed TS SR 3.7.1.1. Revised Markup and Clean TS pages incorporating the approved change are provided in Attachments 2 and 3, respectively.

6. Amendment 234 - no impact to any of the proposed changes previously submitted in References 1 and 2.

7. Amendment 235 - no impact to any of the proposed changes previously submitted in References 1 and 2.

GO2-15-173 Page 2 of 2

8. Amendment 236 is anticipated to be approved by NRC in early first quarter 2016.

Revised Markup and Clean TS pages incorporating the approved changes are provided in Attachments 2 and 3, respectively. Revisions to the following Specifications revised by Amendment 236 are included: TS 3.4.4, TS 3.5.1, TS 3.6.1.6, TS 3.6.1.7, TS 3.6.2.3, TS 3.7.1, TS 3.7.4, TS 3.8.1, and TS 3.8.7.

Additionally, a revised Markup and Clean TS page for correction of Amendment numbers on TS page 3.3.4.1-3 is provided in Attachments 2 and 3, respectively.

References:

1. Letter, GO2-15-007, dated March 17, 2015, WG Hettel (Energy Northwest) to NRC, License Amendment Request for Adoption of Technical Specification Task Force Traveler (TSTF)-425, Revision 3

2. Letter, GO2-15-152, dated November 17, 2015, WG Hettel (Energy Northwest) to NRC, Response to Second Request for Additional Information on License Amendment Request for Adoption of Technical Specification Task Force (TSTF)-

425, Revision 3

GO2-15-173 Marked Up Technical Specification Pages

EOC-RPT Instrumentation 3.3.4.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.3.4.1.2.a Perform CHANNEL CALIBRATION. The Allowable 24 months Value shall be:

TTV - Closure: 7% closed.

SR 3.3.4.1.2.b Perform CHANNEL CALIBRATION. The Allowable 18 months Value shall be:

TGV Fast Closure, Trip Oil Pressure - Low:

1000 psig.

SR 3.3.4.1.3 Verify TTV - Closure and TGV Fast Closure, Trip 18 months Oil Pressure - Low Functions are not bypassed when THERMAL POWER is 30% RTP.

SR 3.3.4.1.4 Perform LOGIC SYSTEM FUNCTIONAL TEST, 24 months including breaker actuation.

SR 3.3.4.1.5 -------------------------------NOTE------------------------------

Breaker arc suppression time may be assumed from the most recent performance of SR 3.3.4.1.6.

Verify the EOC-RPT SYSTEM RESPONSE TIME is 24 months on a within limits. STAGGERED TEST BASIS SR 3.3.4.1.6 Determine RPT breaker arc suppression time. 60 months In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.3.4.1-3 Amendment No. 168,169,225

SRVs - < 25% RTP 3.4.4 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.4.1 Verify the safety function lift setpoints of the required In accordance SRVs are as follows: with the Inservice Testing Program Number of Setpoint SRVs (psig) 2 1165 +/- 34.9 4 1175 +/- 35.2 4 1185 +/- 35.5 4 1195 +/- 35.8 4 1205 +/- 36.1 SR 3.4.4.2 -------------------------------NOTE------------------------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify each required SRV opens when manually 24 months actuated.

In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.4.4-2 Amendment No.149,169,225,236

ECCS - Operating 3.5.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.1.1 Verify, for each ECCS injection/spray subsystem, 31 days the piping is filled with water from the pump discharge valve to the injection valve.

In accordance with the SR 3.5.1.2 ------------------------------NOTE------------------------------- Surveillance Low pressure coolant injection (LPCI) subsystems Frequency may be considered OPERABLE during alignment Control Program and operation for decay heat removal with reactor steam dome pressure less than 48 psig in MODE 3, if capable of being manually realigned and not otherwise inoperable.

Verify each ECCS injection/spray subsystem 31 days manual, power operated, and automatic valve in the flow path, that is not locked, sealed, or otherwise secured in position, is in the correct position.

SR 3.5.1.3 Verify ADS accumulator backup compressed gas 31 days system average pressure in the required bottles is 2200 psig.

SR 3.5.1.4 Verify each ECCS pump develops the specified flow In accordance rate with the specified differential pressure between with the Inservice reactor and suction source. Testing Program DIFFERENTIAL PRESSURE BETWEEN REACTOR AND SYSTEM FLOW RATE SUCTION SOURCE LPCS 6200 gpm 128 psid LPCI 7200 gpm 26 psid HPCS 6350 gpm 200 psid Columbia Generating Station 3.5.1-4 Amendment No. 169,205,225,229,236

ECCS - Operating 3.5.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.1.5 -------------------------------NOTE------------------------------

Vessel injection/spray may be excluded.

Verify each ECCS injection/spray subsystem 24 months actuates on an actual or simulated automatic initiation signal.

SR 3.5.1.6 -------------------------------NOTE------------------------------

Valve actuation may be excluded.

Verify the ADS actuates on an actual or simulated 24 months automatic initiation signal.

SR 3.5.1.7 -------------------------------NOTE------------------------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify each required ADS valve opens when 24 months on a manually actuated. STAGGERED TEST BASIS for each valve solenoid SR 3.5.1.8 -------------------------------NOTE------------------------------

ECCS actuation instrumentation is excluded.

Verify the ECCS RESPONSE TIME for each ECCS 24 months injection/spray subsystem is within limits.

In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.5.1-5 Amendment No. 169,205,225,236

ECCS - Shutdown 3.5.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.2.3 Verify, for each required ECCS injection/spray 31 days subsystem, the piping is filled with water from the pump discharge valve to the injection valve.

SR 3.5.2.4 ------------------------------NOTE------------------------------- In accordance One low pressure coolant injection (LPCI) with the subsystem may be considered OPERABLE during Surveillance alignment and operation for decay heat removal, if Frequency capable of being manually realigned and not Control Program otherwise inoperable.

Verify each required ECCS injection/spray 31 days subsystem manual, power operated, and automatic valve in the flow path, that is not locked, sealed, or otherwise secured in position, is in the correct position.

SR 3.5.2.5 Verify each required ECCS pump develops the In accordance specified flow rate with the specified differential with the Inservice pressure between reactor and suction source. Testing Program DIFFERENTIAL PRESSURE BETWEEN REACTOR AND SYSTEM FLOW RATE SUCTION SOURCE LPCS 6200 gpm 128 psid LPCI 7200 gpm 26 psid HPCS 6350 gpm 200 psid SR 3.5.2.6 -------------------------------NOTE------------------------------

Vessel injection/spray may be excluded.

Verify each required ECCS injection/spray 24 months subsystem actuates on an actual or simulated automatic initiation signal.

Columbia Generating Station 3.5.2-3 Amendment No.169,205,225,229

RHR Drywell Spray 3.6.1.5 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.1.5.1 Verify each RHR drywell spray subsystem manual, 31 days power operated, and automatic valve in the flow In accordance with path that is not locked, sealed, or otherwise secured the Surveillance in position, is in the correct position or can be Frequency Control aligned to the correct position.

Program SR 3.6.1.5.2 Verify each spray nozzle is unobstructed. 10 years Columbia Generating Station 3.6.1.5-2 Amendment No. 169,225,230

Reactor Building-to-Suppression Chamber Vacuum Breakers 3.6.1.6 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME E. Two or more lines with E.1 Restore all vacuum 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months one or more reactor breakers in two lines to building-to-suppression OPERABLE status.

chamber vacuum breakers inoperable for opening.

F. Required Action and F.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months associated Completion Time of Condition A, B AND or E not met.

F.2 Be in MODE 4. 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.1.6.1 ------------------------------NOTES-----------------------------

1. Not required to be met for vacuum breakers that are open during Surveillances.

2. Not required to be met for vacuum breakers open when performing their intended function.

Verify each vacuum breaker is closed. 14 days SR 3.6.1.6.2 Perform a functional test of each vacuum breaker. In accordance with the Inservice Testing Program SR 3.6.1.6.3 Verify the full open setpoint of each vacuum breaker 24 months is 0.5 psid.

In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.6.1.6-2 Amendment No. 149,169,225,236

Suppression Chamber-to-Drywell Vacuum Breakers 3.6.1.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME D. One or more D.1 Close one open vacuum 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months suppression chamber-to- breaker disk.

drywell vacuum breakers with two disks not closed.

E. Required Action and E.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months associated Completion Time of Condition C or D AND not met.

E.2 Be in MODE 4. 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.1.7.1 -------------------------------NOTE------------------------------ In accordance with the Not required to be met for vacuum breakers that are Surveillance Frequency open during Surveillances. Control Program Verify each vacuum breaker is closed. 14 days SR 3.6.1.7.2 Perform a functional test of each required vacuum 31 days breaker.

AND Within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after any discharge of steam to the suppression chamber from the safety/relief valves SR 3.6.1.7.3 Verify the full open setpoint of each required vacuum 24 months breaker is 0.5 psid.

Columbia Generating Station 3.6.1.7-2 Amendment No. 169,202,225,236

RHR Suppression Pool Cooling 3.6.2.3 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.2.3.1 Verify each RHR suppression pool cooling 31 days subsystem manual, power operated, and automatic valve in the flow path that is not locked, sealed, or otherwise secured in position, is in the correct position or can be aligned to the correct position.

SR 3.6.2.3.2 Verify each RHR pump develops a flow rate In accordance 7100 gpm through the associated heat exchanger with the Inservice while operating in the suppression pool cooling Testing Program mode.

In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.6.2.3-2 Amendment No. 169,225,230

SW System and UHS 3.7.1 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME C. Required Action and C.1 --------------NOTE---------------

associated Completion LCO 3.0.4.a is not Time of Condition B not applicable when entering met. MODE 3.

Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months D. Required Action and D.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months associated Completion Time of Condition A not met. AND 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months OR D.2 Be in MODE 4.

Both SW subsystems inoperable.

OR UHS inoperable for reasons other than Condition A.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.1.1 Verify the average water level in the UHS spray 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months ponds is 432 feet 9 inches mean sea level.

SR 3.7.1.2 Verify the average water temperature of each UHS 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months spray pond is 77F.

In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.7.1-2 Amendment No. 169,225,233,236

SW System and UHS 3.7.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.1.3 -------------------------------NOTE------------------------------

Isolation of flow to individual components does not render SW subsystem inoperable.

Verify each SW subsystem manual, power 31 days operated, and automatic valve in the flow path servicing safety related systems or components, that is not locked, sealed, or otherwise secured in position, is in the correct position.

SR 3.7.1.4 Verify average sediment depth in each UHS spray 92 days pond is < 0.5 ft.

SR 3.7.1.5 Verify each SW subsystem actuates on an actual or 24 months simulated initiation signal.

In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.7.1-3 Amendment No. 149,169,225,236

Control Room AC System 3.7.4 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME D. Required Action and D.1 Place OPERABLE control Immediately associated Completion room AC subsystem in Time of Condition A not operation.

met during OPDRVs.

OR D.2 Initiate action to suspend Immediately OPDRVs.

E. Required Action and E.1 Initiate action to suspend Immediately associated Completion OPDRVs.

Time of Condition B not met during OPDRVs.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.4.1 Verify each control room AC subsystem has the 24 months capability to remove the assumed heat load.

In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.7.4-2 Amendment No. 169,199,225,227,236

AC Sources - Operating 3.8.1 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME F. Required Action and F.1 ---------------NOTE--------------

associated Completion LCO 3.0.4.a is not Time of Condition A, B, applicable when entering C, D, or E not met. MODE 3.

Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months G. Three or more required G.1 Enter LCO 3.0.3. Immediately AC sources inoperable.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.1.1 Verify correct breaker alignment and indicated 7 days power availability for each offsite circuit.

SR 3.8.1.2 ------------------------------NOTES-----------------------------

1. All DG starts may be preceded by an engine prelube period and followed by a warmup In accordance period prior to loading. with the Surveillance

2. A modified DG start involving idling and gradual Frequency acceleration to synchronous speed may be Control Program used for this SR as recommended by the manufacturer. When modified start procedures are not used, the time, voltage, and frequency tolerances of SR 3.8.1.7 must be met.

Verify each required DG starts from standby 31 days conditions and achieves steady state:

a. Voltage 3910 V and 4400 V and frequency 58.8 Hz and 61.2 Hz for DG-1 and DG-2; and

b. Voltage 3910 V and 4400 V and frequency 58.8 Hz and 61.2 Hz for DG-3.

Columbia Generating Station 3.8.1-5 Amendment No. 169,181,225,236

Distribution Systems - Operating 3.8.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME C. Required Action and C.1 ---------------NOTE--------------

associated Completion LCO 3.0.4.a is not Time of Condition A or B applicable when entering not met. MODE 3.

Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months D. Division 1 250 V DC D.1 Declare associated Immediately electrical power supported feature(s) distribution subsystem inoperable.

inoperable.

E. One or more Division 3 E.1 Declare High Pressure Immediately AC or DC electrical Core Spray System power distribution inoperable.

subsystems inoperable.

F. Two or more divisions F.1 Enter LCO 3.0.3. Immediately with inoperable electrical power distribution subsystems that result in a loss of function.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.7.1 Verify correct breaker alignments and indicated 7 days power availability to required AC and DC electrical power distribution subsystems.

In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.8.7-2 Amendment No. 149,169,225,236

GO2-15-173 Clean Technical Specification Pages

RPS Instrumentation (After Implementation of PRNM Upgrade) 3.3.1.1 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME I. As required by Required I.1 Initiate alternate method to 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months Action D.1 and detect and suppress referenced in thermal hydraulic instability Table 3.3.1.1-1. oscillations.

AND

NOTE-------------

LCO 3.0.4 is not applicable.

I.2 Restore required channels 120 days to OPERABLE J. Required Action and J.1 Reduce THERMAL 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months associated Completion POWER to less than the Time of Condition I not value specified in the met. COLR.

SURVEILLANCE REQUIREMENTS

NOTES----------------------------------------------------------

1. Refer to Table 3.3.1.1-1 to determine which SRs apply for each RPS Function.

2. When a channel is placed in an inoperable status solely for performance of required Surveillances, entry into associated Conditions and Required Actions may be delayed for up to 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months provided the associated Function maintains RPS trip capability.

SURVEILLANCE FREQUENCY SR 3.3.1.1.1 Perform CHANNEL CHECK. In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.3.1.1-11 Amendment No. 169,225,226

RPS Instrumentation (After Implementation of PRNM Upgrade) 3.3.1.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.3.1.1.2 -------------------------------NOTE------------------------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after THERMAL POWER 25% RTP.

Verify the absolute difference between the average In accordance power range monitor (APRM) channels and the with the calculated power 2% RTP while operating at Surveillance Frequency 25% RTP.

Control Program SR 3.3.1.1.3 -------------------------------NOTE------------------------------

Not required to be performed when entering MODE 2 from MODE 1 until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after entering MODE 2.

Perform CHANNEL FUNCTIONAL TEST. In accordance with the Surveillance Frequency Control Program SR 3.3.1.1.4 Perform CHANNEL FUNCTIONAL TEST. In accordance with the Surveillance Frequency Control Program SR 3.3.1.1.5 Verify the source range monitor (SRM) and Prior to intermediate range monitor (IRM) channels overlap. withdrawing SRMs from the fully inserted position SR 3.3.1.1.6 -------------------------------NOTE------------------------------

Only required to be met during entry into MODE 2 from MODE 1.

Verify the IRM and APRM channels overlap. In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.3.1.1-12 Amendment No. 169,225,226

RPS Instrumentation (After Implementation of PRNM Upgrade) 3.3.1.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.3.1.1.7 Calibrate the local power range monitors. In accordance with the Surveillance Frequency Control Program SR 3.3.1.1.8 Perform CHANNEL FUNCTIONAL TEST. In accordance with the Surveillance Frequency Control Program SR 3.3.1.1.9 Deleted.

SR 3.3.1.1.10 ------------------------------NOTES---------------------------

1. Neutron detectors are excluded.

2. For Function 1, not required to be performed when entering MODE 2 from MODE 1 until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after entering MODE 2.

3. For Functions 2.b and 2.f, the recirculation flow transmitters that feed the APRMs are included.

In accordance with Perform CHANNEL CALIBRATION. the Surveillance Frequency Control Program SR 3.3.1.1.11 Deleted.

SR 3.3.1.1.12 Verify Turbine Throttle Valve - Closure, and In accordance with Turbine Governor Valve Fast Closure Trip Oil the Surveillance Pressure - Low Functions are not bypassed when Frequency Control THERMAL POWER is 30% RTP. Program SR 3.3.1.1.13 Perform CHANNEL FUNCTIONAL TEST. In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.3.1.1-13 Amendment No. 169,225,226

RPS Instrumentation (After Implementation of PRNM Upgrade) 3.3.1.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.3.1.1.14 Perform LOGIC SYSTEM FUNCTIONAL TEST. In accordance with the Surveillance Frequency Control Program SR 3.3.1.1.15 ------------------------------NOTES-----------------------------

1. Neutron detectors are excluded.

2. Channel sensors for Functions 3 and 4 are excluded.

Verify the RPS RESPONSE TIME is within limits. In accordance with the Surveillance Frequency Control Program SR 3.3.1.1.16 ------------------------------NOTES-----------------------------

1. For Function 2.a, not required to be performed when entering MODE 2 from MODE 1 until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after entering MODE 2.

2. For Functions 2.b and 2.f, the CHANNEL FUNCTIONAL TEST includes the recirculation flow input processing, excluding the flow transmitters.

Perform CHANNEL FUNCTIONAL TEST. In accordance with the Surveillance Frequency Control Program SR 3.3.1.1.17 Verify the OPRM is not bypassed when APRM In accordance Simulated Thermal Power is greater than or equal to with the the value specified in the COLR and recirculation Surveillance drive flow is less than the value specified in the Frequency COLR. Control Program Columbia Generating Station 3.3.1.1-14 Amendment No. 169,225,226

EOC-RPT Instrumentation 3.3.4.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.3.4.1.2.a Perform CHANNEL CALIBRATION. The Allowable In accordance with Value shall be: the Surveillance Frequency Control TTV - Closure: 7% closed. Program SR 3.3.4.1.2.b Perform CHANNEL CALIBRATION. The Allowable In accordance with Value shall be: the Surveillance Frequency Control TGV Fast Closure, Trip Oil Pressure - Low: Program 1000 psig.

SR 3.3.4.1.3 Verify TTV - Closure and TGV Fast Closure, Trip In accordance with Oil Pressure - Low Functions are not bypassed the Surveillance when THERMAL POWER is 30% RTP. Frequency Control Program SR 3.3.4.1.4 Perform LOGIC SYSTEM FUNCTIONAL TEST, In accordance with including breaker actuation. the Surveillance Frequency Control Program SR 3.3.4.1.5 -------------------------------NOTE------------------------------

Breaker arc suppression time may be assumed from the most recent performance of SR 3.3.4.1.6.

Verify the EOC-RPT SYSTEM RESPONSE TIME is In accordance with within limits. the Surveillance Frequency Control Program SR 3.3.4.1.6 Determine RPT breaker arc suppression time. In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.3.4.1-3 Amendment No. 168,169,225

SRVs - < 25% RTP 3.4.4 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.4.1 Verify the safety function lift setpoints of the required In accordance SRVs are as follows: with the Inservice Testing Program Number of Setpoint SRVs (psig) 2 1165 +/- 34.9 4 1175 +/- 35.2 4 1185 +/- 35.5 4 1195 +/- 35.8 4 1205 +/- 36.1 SR 3.4.4.2 -------------------------------NOTE------------------------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify each required SRV opens when manually In accordance actuated. with the Surveillance Frequency Control Program Columbia Generating Station 3.4.4-2 Amendment No. 149,169,225,236

ECCS - Operating 3.5.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.1.1 Verify, for each ECCS injection/spray subsystem, In accordance the piping is filled with water from the pump with the discharge valve to the injection valve. Surveillance Frequency Control Program SR 3.5.1.2 ------------------------------NOTE-------------------------------

Low pressure coolant injection (LPCI) subsystems may be considered OPERABLE during alignment and operation for decay heat removal with reactor steam dome pressure less than 48 psig in MODE 3, if capable of being manually realigned and not otherwise inoperable.

Verify each ECCS injection/spray subsystem In accordance manual, power operated, and automatic valve in the with the flow path, that is not locked, sealed, or otherwise Surveillance secured in position, is in the correct position. Frequency Control Program SR 3.5.1.3 Verify ADS accumulator backup compressed gas In accordance system average pressure in the required bottles is with the 2200 psig. Surveillance Frequency Control Program SR 3.5.1.4 Verify each ECCS pump develops the specified flow In accordance rate with the specified differential pressure between with the Inservice reactor and suction source. Testing Program DIFFERENTIAL PRESSURE BETWEEN REACTOR AND SYSTEM FLOW RATE SUCTION SOURCE LPCS 6200 gpm 128 psid LPCI 7200 gpm 26 psid HPCS 6350 gpm 200 psid Columbia Generating Station 3.5.1-4 Amendment No. 169,205,225,229,236

ECCS - Operating 3.5.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.1.5 -------------------------------NOTE------------------------------

Vessel injection/spray may be excluded.

Verify each ECCS injection/spray subsystem In accordance actuates on an actual or simulated automatic with the initiation signal. Surveillance Frequency Control Program SR 3.5.1.6 -------------------------------NOTE------------------------------

Valve actuation may be excluded.

Verify the ADS actuates on an actual or simulated In accordance automatic initiation signal. with the Surveillance Frequency Control Program SR 3.5.1.7 -------------------------------NOTE------------------------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify each required ADS valve opens when In accordance manually actuated. with the Surveillance Frequency Control Program SR 3.5.1.8 -------------------------------NOTE------------------------------

ECCS actuation instrumentation is excluded.

Verify the ECCS RESPONSE TIME for each ECCS In accordance injection/spray subsystem is within limits. with the Surveillance Frequency Control Program Columbia Generating Station 3.5.1-5 Amendment No. 169,205,225,236

ECCS - Shutdown 3.5.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.2.3 Verify, for each required ECCS injection/spray In accordance subsystem, the piping is filled with water from the with the pump discharge valve to the injection valve. Surveillance Frequency Control Program SR 3.5.2.4 ------------------------------NOTE-------------------------------

One low pressure coolant injection (LPCI) subsystem may be considered OPERABLE during alignment and operation for decay heat removal, if capable of being manually realigned and not otherwise inoperable.

Verify each required ECCS injection/spray In accordance subsystem manual, power operated, and automatic with the valve in the flow path, that is not locked, sealed, or Surveillance otherwise secured in position, is in the correct Frequency position. Control Program SR 3.5.2.5 Verify each required ECCS pump develops the In accordance specified flow rate with the specified differential with the Inservice pressure between reactor and suction source. Testing Program DIFFERENTIAL PRESSURE BETWEEN REACTOR AND SYSTEM FLOW RATE SUCTION SOURCE LPCS 6200 gpm 128 psid LPCI 7200 gpm 26 psid HPCS 6350 gpm 200 psid Columbia Generating Station 3.5.2-3 Amendment No. 169,205,225,229

ECCS - Shutdown 3.5.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.2.6 -------------------------------NOTE------------------------------

Vessel injection/spray may be excluded.

Verify each required ECCS injection/spray In accordance subsystem actuates on an actual or simulated with the automatic initiation signal. Surveillance Frequency Control Program Columbia Generating Station 3.5.2-4 Amendment No.

RHR Drywell Spray 3.6.1.5 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.1.5.1 Verify each RHR drywell spray subsystem manual, In accordance power operated, and automatic valve in the flow with the path that is not locked, sealed, or otherwise secured Surveillance in position, is in the correct position or can be Frequency aligned to the correct position. Control Program SR 3.6.1.5.2 Verify each spray nozzle is unobstructed. In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.6.1.5-2 Amendment No. 169,225,230

Reactor Building-to-Suppression Chamber Vacuum Breakers 3.6.1.6 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME E. Two or more lines with E.1 Restore all vacuum 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months one or more reactor breakers in two lines to building-to-suppression OPERABLE status.

chamber vacuum breakers inoperable for opening.

F. Required Action and F.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months associated Completion Time of Condition A, B AND or E not met.

F.2 Be in MODE 4. 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.1.6.1 ------------------------------NOTES-----------------------------

1. Not required to be met for vacuum breakers that are open during Surveillances.

2. Not required to be met for vacuum breakers open when performing their intended function.

Verify each vacuum breaker is closed. In accordance with the Surveillance Frequency Control Program SR 3.6.1.6.2 Perform a functional test of each vacuum breaker. In accordance with the Inservice Testing Program Columbia Generating Station 3.6.1.6-2 Amendment No. 149,169,225,236

Reactor Building-to-Suppression Chamber Vacuum Breakers 3.6.1.6 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.1.6.3 Verify the full open setpoint of each vacuum breaker In accordance is 0.5 psid. with the Surveillance Frequency Control Program Columbia Generating Station 3.6.1.6-3 Amendment No.

Suppression Chamber-to-Drywell Vacuum Breakers 3.6.1.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME D. One or more D.1 Close one open vacuum 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months suppression chamber-to- breaker disk.

drywell vacuum breakers with two disks not closed.

E. Required Action and E.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months associated Completion Time of Condition C or D AND not met.

E.2 Be in MODE 4. 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.1.7.1 -------------------------------NOTE------------------------------

Not required to be met for vacuum breakers that are open during Surveillances.

Verify each vacuum breaker is closed. In accordance with the Surveillance Frequency Control Program Columbia Generating Station 3.6.1.7-2 Amendment No. 169,202,225,236

Suppression Chamber-to-Drywell Vacuum Breakers 3.6.1.7 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.1.7.2 Perform a functional test of each required vacuum In accordance breaker. with the Surveillance Frequency Control Program AND Within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after any discharge of steam to the suppression chamber from the safety/relief valves SR 3.6.1.7.3 Verify the full open setpoint of each required In accordance vacuum breaker is 0.5 psid. with the Surveillance Frequency Control Program Columbia Generating Station 3.6.1.7-3 Amendment No.

RHR Suppression Pool Cooling 3.6.2.3 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.2.3.1 Verify each RHR suppression pool cooling In accordance subsystem manual, power operated, and automatic with the valve in the flow path that is not locked, sealed, or Surveillance otherwise secured in position, is in the correct Frequency position or can be aligned to the correct position. Control Program SR 3.6.2.3.2 Verify each RHR pump develops a flow rate In accordance 7100 gpm through the associated heat exchanger with the Inservice while operating in the suppression pool cooling Testing Program mode.

Columbia Generating Station 3.6.2.3-2 Amendment No. 169,225,230

SW System and UHS 3.7.1 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME C. Required Action and C.1 --------------NOTE---------------

associated Completion LCO 3.0.4.a is not Time of Condition B not applicable when entering met. MODE 3.

Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months D. Required Action and D.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months associated Completion Time of Condition A not met. AND 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months OR D.2 Be in MODE 4.

Both SW subsystems inoperable.

OR UHS inoperable for reasons other than Condition A.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.1.1 Verify the average water level in the UHS spray In accordance ponds is 432 feet 9 inches mean sea level. with the Surveillance Frequency Control Program SR 3.7.1.2 Verify the average water temperature of each UHS In accordance spray pond is 77F. with the Surveillance Frequency Control Program Columbia Generating Station 3.7.1-2 Amendment No. 169,225,233,236

SW System and UHS 3.7.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.1.3 -------------------------------NOTE------------------------------

Isolation of flow to individual components does not render SW subsystem inoperable.

Verify each SW subsystem manual, power In accordance operated, and automatic valve in the flow path with the servicing safety related systems or components, Surveillance that is not locked, sealed, or otherwise secured in Frequency position, is in the correct position. Control Program SR 3.7.1.4 Verify average sediment depth in each UHS spray In accordance pond is < 0.5 ft. with the Surveillance Frequency Control Program SR 3.7.1.5 Verify each SW subsystem actuates on an actual or In accordance simulated initiation signal. with the Surveillance Frequency Control Program Columbia Generating Station 3.7.1-3 Amendment No. 149,169,225,236

Control Room AC System 3.7.4 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME D. Required Action and D.1 Place OPERABLE control Immediately associated Completion room AC subsystem in Time of Condition A not operation.

met during OPDRVs.

OR D.2 Initiate action to suspend Immediately OPDRVs.

E. Required Action and E.1 Initiate action to suspend Immediately associated Completion OPDRVs.

Time of Condition B not met during OPDRVs.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.4.1 Verify each control room AC subsystem has the In accordance capability to remove the assumed heat load. with the Surveillance Frequency Control Program Columbia Generating Station 3.7.4-2 Amendment No. 169,199,225,227,236

AC Sources - Operating 3.8.1 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME F. Required Action and F.1 ---------------NOTE--------------

associated Completion LCO 3.0.4.a is not Time of Condition A, B, applicable when entering C, D, or E not met. MODE 3.

Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months G. Three or more required G.1 Enter LCO 3.0.3. Immediately AC sources inoperable.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.1.1 Verify correct breaker alignment and indicated In accordance with power availability for each offsite circuit. the Surveillance Frequency Control Program SR 3.8.1.2 ------------------------------NOTES----------------------------

1. All DG starts may be preceded by an engine prelube period and followed by a warmup period prior to loading.

2. A modified DG start involving idling and gradual acceleration to synchronous speed may be used for this SR as recommended by the manufacturer. When modified start procedures are not used, the time, voltage, and frequency tolerances of SR 3.8.1.7 must be met.

Verify each required DG starts from standby In accordance with conditions and achieves steady state: the Surveillance Frequency Control

a. Voltage 3910 V and 4400 V and frequency Program 58.8 Hz and 61.2 Hz for DG-1 and DG-2; and

b. Voltage 3910 V and 4400 V and frequency 58.8 Hz and 61.2 Hz for DG-3.

Columbia Generating Station 3.8.1-5 Amendment No. 169,181,225,236

Distribution Systems - Operating 3.8.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME C. Required Action and C.1 ---------------NOTE--------------

associated Completion LCO 3.0.4.a is not Time of Condition A or B applicable when entering not met. MODE 3.

Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months D. Division 1 250 V DC D.1 Declare associated Immediately electrical power supported feature(s) distribution subsystem inoperable.

inoperable.

E. One or more Division 3 E.1 Declare High Pressure Immediately AC or DC electrical Core Spray System power distribution inoperable.

subsystems inoperable.

F. Two or more divisions F.1 Enter LCO 3.0.3. Immediately with inoperable electrical power distribution subsystems that result in a loss of function.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.7.1 Verify correct breaker alignments and indicated In accordance power availability to required AC and DC electrical with the power distribution subsystems. Surveillance Frequency Control Program Columbia Generating Station 3.8.7-2 Amendment No. 149,169,225,236

GO2-15-173 Marked Up Technical Specification Bases Pages For Information Only

PCIVs B 3.6.1.3 BASES SURVEILLANCE REQUIREMENTS (continued)

SR 3.6.1.3.6 Verifying that the full closure isolation time of each MSIV is within the specified limits is required to demonstrate OPERABILITY. The full closure isolation time test ensures that the MSIV will isolate in a time period that does not exceed the times assumed in the DBA and transient analyses. The Frequency of this SR is in accordance with the Inservice Testing Program.

SR 3.6.1.3.7 Automatic PCIVs close on a primary containment isolation signal to prevent leakage of radioactive material from primary containment following a DBA. This SR ensures that each automatic PCIV will actuate to its isolation position on a primary containment isolation signal. The LOGIC SYSTEM FUNCTIONAL TEST in LCO 3.3.6.1, "Primary Containment Isolation Instrumentation," overlaps this SR to provide complete testing of the safety function. The 24 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage and the potential for an unplanned transient if the Surveillance were performed with the reactor at power. Operating experience has shown that these components usually pass this Surveillance when performed at the 24 month Frequency. Therefore, the Frequency was concluded to be acceptable from a reliability standpoint.The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.6.1.3.8 during the interval This SR requires a demonstration that a representative sample of reactor instrument lines excess flow check valves (EFCVs) are OPERABLE by verifying that each tested valve actuates to the isolation position on an actual or simulated instrument line break condition. The representative sample consists of an approximately equal number of EFCVs, such that each EFCV is tested at least once every 10 years (nominal). In addition, the EFCVs in the sample are representative of the various plant configurations, models, sizes and operating environments. This ensures that any potentially common problem with a specific type or application of EFCV is detected at the earliest possible time. This SR provides assurance that the reactor instrumentation lines EFCVs will perform as designed. The excess flow check valves in reactor instrument lines are tested by providing an instrument line break signal with pressure at 85 psig to 1050 psig, and at no more than 212°F, RPV coolant temperature, while the EFCV is being exercised. Testing within this Columbia Generating Station B 3.6.1.3-12 Revision 73

PCIVs B 3.6.1.3 pressure range provides a high degree of assurance that these valves will close during an instrument line break while at normal operating pressure.

Columbia Generating Station B 3.6.1.3-13 Revision 73

PCIVs B 3.6.1.3 BASES SURVEILLANCE REQUIREMENTS (continued)

The 24 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage and the potential for an unplanned transient if the Surveillance were performed with the reactor at power. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The nominal 10 year interval is based on performance testing. Furthermore, any EFCV failures will be evaluated to determine if additional testing in that test interval is warranted to ensure overall reliability is maintained. Operating experience has demonstrated that these components are highly reliable and that failures to isolate are very infrequent. Therefore, testing of a representative sample was concluded to be acceptable from a reliability standpoint (Reference 5). In addition, due to operational concerns, the Surveillance should not be performed during MODES 1, 2, or 3. This restriction has been established to limit the thermal cycles at the containment penetration.

SR 3.6.1.3.9 The TIP shear isolation valves are actuated by explosive charges. An in place functional test is not possible with this design. The explosive squib is removed and tested to provide assurance that the valves will actuate when required. The replacement charge for the explosive squib shall be from the same manufactured batch as the one fired or from another batch that has been certified by having one of the batch successfully fired.

Other administrative controls, such as those that limit the shelf life and operating life, as applicable, of the explosive charges, must be followed.

The Frequency of 24 months on a STAGGERED TEST BASIS is considered adequate given the administrative controls on replacement charges and the frequent checks of circuit continuity (SR 3.6.1.3.4).The Surveillance Frequency is controlled under the Surveillance Frequency Control Progra.

SR 3.6.1.3.10 This SR ensures that the leakage rate of secondary containment bypass leakage paths is less than the specified leakage rate. This provides assurance that the assumptions in the radiological evaluations that form the basis of the FSAR (Ref. 1) are met. The leakage rate of each bypass leakage path is assumed to be the maximum pathway leakage (leakage through the worse of the two isolation valves) unless the penetration is isolated by use of one closed and de-activated automatic valve, closed manual valve, or blind flange. In this case, the leakage rate of the isolated bypass leakage path is assumed to be the actual pathway leakage through the isolation device. If both isolation valves in the Columbia Generating Station B 3.6.1.3-14 Revision 73