ML110880261

Licensee Slides from March 29, 2011 Pre-Licensing Meeting with Arizona Public Service Company to Discuss Potential Submittal of a License Amendment Request to Revise TS Pages

ML110880261
Person / Time
Site:	Palo Verde
Issue date:	03/29/2011
From:	Arizona Public Service Co
To:	Plant Licensing Branch IV
Gibson, Lauren, NRR/DORL/LPL4, 415-1056
Shared Package
ML110880244	List: ML110880261 ML110880275
References
TAC ME5233, TAC ME5234, TAC ME5235
Download: ML110880261 (26)

Text

Palo Verde Nuclear Generating Station (PVNGS)

License Amendment Request Pre-Licensing Meeting Palo Verde Nuclear Generating Station (PVNGS)

License Amendment Request Pre-Licensing Meeting Arizona Public Service Company (APS)

Presentation to U.S. Nuclear Regulatory Commission (NRC) Staff Rockville, MD - March 29, 2011 Arizona Public Service Company (APS)

Presentation to U.S. Nuclear Regulatory Commission (NRC) Staff Rockville, MD - March 29, 2011

Agenda Agenda

• Introductions

• November 2010 NRC/APS Meeting

• Revised License Amendment Request (LAR)

• APS Responses to NRC Questions

• Introductions

• November 2010 NRC/APS Meeting

• Revised License Amendment Request (LAR)

• APS Responses to NRC Questions

• APS Responses to NRC Questions

• Q&A

• APS Responses to NRC Questions

• Q&A 2

November 2010 NRC/APS Meeting November 2010 NRC/APS Meeting

• APS submitted LAR on August 25, 2010

• Nonconservative Technical Specification (TS)

- TS 3.7.4, Atmospheric Dump Valves (ADVs)

- Limiting Condition for Operation - two operable ADVs

• APS submitted LAR on August 25, 2010

• Nonconservative Technical Specification (TS)

- TS 3.7.4, Atmospheric Dump Valves (ADVs)

- Limiting Condition for Operation - two operable ADVs g

p p

- Single failure criterion - four operable ADVs

• PVNGS main steam system

• ADV design and licensing bases

• ADV tests and performance history

• NUREG-1432 Standard Technical Specifications

• Combustion Engineering plants g

p p

- Single failure criterion - four operable ADVs

• PVNGS main steam system

• ADV design and licensing bases

• ADV tests and performance history

• NUREG-1432 Standard Technical Specifications

• Combustion Engineering plants 3

November 2010 NRC/APS Meeting November 2010 NRC/APS Meeting

• Description of proposed LAR

- TS LCO 3.7.4

• Two ADV lines per Steam Generator (SG) to be operable

- Condition A

• One inoperable ADV line - Continued operation for up to 7

• Description of proposed LAR

- TS LCO 3.7.4

• Two ADV lines per Steam Generator (SG) to be operable

- Condition A

• One inoperable ADV line - Continued operation for up to 7 One inoperable ADV line Continued operation for up to 7 days

• Separate condition entry allowed for each SG

- Condition B

• Two inoperable ADV lines on one SG - Continued operation for up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />

- Condition C

• Four inoperable ADV lines - Continued operation for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> One inoperable ADV line Continued operation for up to 7 days

• Separate condition entry allowed for each SG

- Condition B

• Two inoperable ADV lines on one SG - Continued operation for up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />

- Condition C

• Four inoperable ADV lines - Continued operation for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 4

November 2010 NRC/APS Meeting November 2010 NRC/APS Meeting

• Feedback from NRC staff

• APS withdrew LAR on December 9, 2010

• NRC acknowledgment of December 21, 2010

- Pre-licensing meeting

• Feedback from NRC staff

• APS withdrew LAR on December 9, 2010

• NRC acknowledgment of December 21, 2010

- Pre-licensing meeting Pre licensing meeting

- Four NRC Staff questions Pre licensing meeting

- Four NRC Staff questions 5

Revised LAR Revised LAR

• Limiting Condition for Operation (LCO)

• Conditions

- Configurations with one or more inoperable ADVs

- Action statements

• Limiting Condition for Operation (LCO)

• Conditions

- Configurations with one or more inoperable ADVs

- Action statements

- Completion times

• Bases

- Safety analyses

- Single failures

- NUREG-1432 STS and STS Bases

- Other governing Technical Specifications

- Completion times

• Bases

- Safety analyses

- Single failures

- NUREG-1432 STS and STS Bases

- Other governing Technical Specifications 6

Revised LAR Revised LAR

• LCO 3.7.4, Atmospheric Dump Valves (ADVs)

- Four ADV lines shall be operable

- Modes 1, 2, 3, and 4 (when SG relied upon for heat removal)

• Bases for LCO

• LCO 3.7.4, Atmospheric Dump Valves (ADVs)

- Four ADV lines shall be operable

- Modes 1, 2, 3, and 4 (when SG relied upon for heat removal)

• Bases for LCO

• Bases for LCO

- Resolves non-conservative TS

- Design Basis Events

- General Design Criteria (GDC) 34 - Heat removal

- Safety analyses (e.g., LOCA) - credit one ADV per SG

- Single failure - one ADV per SG rendered inoperable

• Bases for LCO

- Resolves non-conservative TS

- Design Basis Events

- General Design Criteria (GDC) 34 - Heat removal

- Safety analyses (e.g., LOCA) - credit one ADV per SG

- Single failure - one ADV per SG rendered inoperable 7

Revised LAR Revised LAR

• Condition A

- One required ADV line inoperable

- Separate condition entry allowed for each SG

• Action

• Condition A

- One required ADV line inoperable

- Separate condition entry allowed for each SG

• Action

- Restore ADV line to operable status

• Completion time

- 7 days

- Restore ADV line to operable status

• Completion time

- 7 days 8

Revised LAR Revised LAR

• Bases for Condition A

- STS day CT for one inoperable ADV on one SG

- Separate condition entry (one ADV inoperable per SG)

• Plant configuration consistent with safety analyses Si l

f il t

t l t d d i

CT (GL 80 030)

• Bases for Condition A

- STS day CT for one inoperable ADV on one SG

- Separate condition entry (one ADV inoperable per SG)

• Plant configuration consistent with safety analyses Si l

f il t

t l t d d i

CT (GL 80 030)

• Single failure not postulated during CT (GL 80-030)

• Maintenance considerations

• Assessment of Risk - More than one hundred times below allowable RG 1.177 limits - Green RMAL

• More restrictive TS exist for certain electrical components that support ADV operability

• Single failure not postulated during CT (GL 80-030)

• Maintenance considerations

• Assessment of Risk - More than one hundred times below allowable RG 1.177 limits - Green RMAL

• More restrictive TS exist for certain electrical components that support ADV operability 9

Revised LAR Revised LAR 10

Revised LAR Revised LAR

• Bases for Condition A (continued)

- More restrictive TS

• TS LCO 3.8.4, DC Sources - Operating

• TS LCO 3.8.7, Inverters - Operating TS LCO 3 8 9 Di t ib ti S

t O

ti

• Bases for Condition A (continued)

- More restrictive TS

• TS LCO 3.8.4, DC Sources - Operating

• TS LCO 3.8.7, Inverters - Operating TS LCO 3 8 9 Di t ib ti S

t O

ti

• TS LCO 3.8.9, Distribution Systems - Operating

• Examples

- One DC electrical power distribution subsystem inoperable -

Restore within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />

- One AC vital instrument bus electrical power distribution subsystem inoperable - Restore within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />

- One inverter inoperable - Restore within 7 days

- Unit shutdown required if actions and CTs not met

• TS LCO 3.8.9, Distribution Systems - Operating

• Examples

- One DC electrical power distribution subsystem inoperable -

Restore within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />

- One AC vital instrument bus electrical power distribution subsystem inoperable - Restore within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />

- One inverter inoperable - Restore within 7 days

- Unit shutdown required if actions and CTs not met 11

Revised LAR Revised LAR

• Bases for Condition A (continued)

- Other guidance

• PVNGS TS 3.0.3

- LCO and actions not met / action not provided Take action within one hour to initiate unit shutdown

• Bases for Condition A (continued)

- Other guidance

• PVNGS TS 3.0.3

- LCO and actions not met / action not provided Take action within one hour to initiate unit shutdown

- Take action within one hour to initiate unit shutdown

• STS 3.7.4 Condition B hour CT for two inoperable ADVs

- CT is too restrictive for analyzed plant configuration

• NRC staff guidance (ML071230105)

-... The STS typically allows a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or longer Completion Time for Conditions where the remaining operable equipment is able to mitigate postulated accidents without assuming a concurrent single active failure....

- Take action within one hour to initiate unit shutdown

• STS 3.7.4 Condition B hour CT for two inoperable ADVs

- CT is too restrictive for analyzed plant configuration

• NRC staff guidance (ML071230105)

-... The STS typically allows a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or longer Completion Time for Conditions where the remaining operable equipment is able to mitigate postulated accidents without assuming a concurrent single active failure....

12

Revised LAR Revised LAR

• Condition B

- Two or more ADV lines inoperable AND

- Both ADV lines inoperable on one or more SGs

• Condition B

- Two or more ADV lines inoperable AND

- Both ADV lines inoperable on one or more SGs

• Action

- Restore all but one ADV line to operable status on each affected SG

• Completion time

- 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />

• Action

- Restore all but one ADV line to operable status on each affected SG

• Completion time

- 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 13

Revised LAR Revised LAR

• Bases for Condition B

- STS hour CT for two or more inoperable ADVs

- STS Bases hour CT based on the availability of the Steam Bypass Control System (SBCS) and

• Bases for Condition B

- STS hour CT for two or more inoperable ADVs

- STS Bases hour CT based on the availability of the Steam Bypass Control System (SBCS) and MSSVs, and the low probability of an event occurring during this period

- Condition B modified to account for Condition A separate condition entry

- Requires timely restoration of plant configuration to analyzed configuration MSSVs, and the low probability of an event occurring during this period

- Condition B modified to account for Condition A separate condition entry

- Requires timely restoration of plant configuration to analyzed configuration 14

Revised LAR Revised LAR

• Condition C (not revised)

- Required action and associated CT not met

• Actions and CTs

- Be in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and

• Condition C (not revised)

- Required action and associated CT not met

• Actions and CTs

- Be in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and

- Be in Mode 4 without reliance on SG for heat removal within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />

• Bases for Condition C

- Same as STS

- Same as current TS 3.7.4, Condition C

- Be in Mode 4 without reliance on SG for heat removal within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />

• Bases for Condition C

- Same as STS

- Same as current TS 3.7.4, Condition C 15

APS Responses to NRC Questions APS Responses to NRC Questions

• Question #1

- The licensee is requesting "A separate condition entry for each SG" for Condition "A" for one ADV inoperable for a 7-day completion time (CT).

• Question #1

- The licensee is requesting "A separate condition entry for each SG" for Condition "A" for one ADV inoperable for a 7-day completion time (CT).

Standard Technical Specifications (STS) do not permit separate condition entry. Please justify why separate entry condition would be acceptable.

Standard Technical Specifications (STS) do not permit separate condition entry. Please justify why separate entry condition would be acceptable.

16

APS Responses to NRC Questions APS Responses to NRC Questions

• Response to Question #1

- Separate entry is justified by ADV redundancy

• Two ADVs (one per SG) remain operable

• Plant configuration analyzed (e.g., LOCA)

- Other methods to support heat removal

• Response to Question #1

- Separate entry is justified by ADV redundancy

• Two ADVs (one per SG) remain operable

• Plant configuration analyzed (e.g., LOCA)

- Other methods to support heat removal pp

• Steam Bypass Control System (SBCS)

• Main Steam Safety Valves (MSSVs) pp

• Steam Bypass Control System (SBCS)

• Main Steam Safety Valves (MSSVs) 17

APS Responses to NRC Questions APS Responses to NRC Questions

• Question #2

- The licensee is requesting a 72-hour completion time for two ADVs inoperable on one SG for Condition "B.

STS Condition "B" does not allow two inoperable

• Question #2

- The licensee is requesting a 72-hour completion time for two ADVs inoperable on one SG for Condition "B.

STS Condition "B" does not allow two inoperable ADVs on one SG for more than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Please explain how a design-basis event could be mitigated if an accident on the SG with the operable ADV results in no ADVs available for accident mitigation.

ADVs on one SG for more than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Please explain how a design-basis event could be mitigated if an accident on the SG with the operable ADV results in no ADVs available for accident mitigation.

18

APS Responses to NRC Questions APS Responses to NRC Questions

• Response to Question #2

- Revised LAR is more restrictive

- Would not allow continued operation for up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> with two ADV lines inoperable on one SG

- Would allow continued operation for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in this

• Response to Question #2

- Revised LAR is more restrictive

- Would not allow continued operation for up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> with two ADV lines inoperable on one SG

- Would allow continued operation for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in this configuration

- Consistent with STS configuration

- Consistent with STS 19

APS Responses to NRC Questions APS Responses to NRC Questions

• Question #3

- STS does not permit separate entry conditions on multiple SGs, and the limiting condition for operation is written to address only one SG at a time; therefore, l

SG i i

d h

ADV

• Question #3

- STS does not permit separate entry conditions on multiple SGs, and the limiting condition for operation is written to address only one SG at a time; therefore, l

SG i i

d h

ADV only one SG is permitted to have two ADVs inoperable. In its LAR, the licensee assumes that STS Condition "B" allows two ADVs to be inoperable on two SGs for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and uses this logic on page 9 of its LAR to help justify that the proposed 72-hour CT is more conservative than STS. Please justify the assumption and provide additional information to show that the design basis can be met.

only one SG is permitted to have two ADVs inoperable. In its LAR, the licensee assumes that STS Condition "B" allows two ADVs to be inoperable on two SGs for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and uses this logic on page 9 of its LAR to help justify that the proposed 72-hour CT is more conservative than STS. Please justify the assumption and provide additional information to show that the design basis can be met.

20

APS Responses to NRC Questions APS Responses to NRC Questions

• Response to Question #3

- Addressed by responses to Questions #1 and #2

• Response to Question #3

- Addressed by responses to Questions #1 and #2 21

APS Responses to NRC Questions APS Responses to NRC Questions

• Question #4

- The NRC staff understands that the licensee is requesting a CT in order to perform maintenance and testing of the ADVs while the units are on-line.

• Question #4

- The NRC staff understands that the licensee is requesting a CT in order to perform maintenance and testing of the ADVs while the units are on-line.

Please provide information to show the testing is a mandatory or a self-imposed requirement based upon plant-specific equipment reliability.

Please provide information to show the testing is a mandatory or a self-imposed requirement based upon plant-specific equipment reliability.

22

APS Responses to NRC Questions APS Responses to NRC Questions

• Response to Question #4 TS 5.5.8, Inservice Testing Program

- Quarterly Test Frequencies Specified by ASME OM Code

• Check valve closure

- Instrument air and N2 accumulator supply check valves Use Drop Test Method supplied by N Accumulator

• Response to Question #4 TS 5.5.8, Inservice Testing Program

- Quarterly Test Frequencies Specified by ASME OM Code

• Check valve closure

- Instrument air and N2 accumulator supply check valves Use Drop Test Method supplied by N Accumulator

- Use Drop Test Method supplied by N2 Accumulator

• Bidirectional Open Test

• ADV Stroke timing / Fail Safe / N2 Supply System

- Performed quarterly and prior to startup following refueling

- Use Drop Test Method supplied by N2 Accumulator

• Bidirectional Open Test

• ADV Stroke timing / Fail Safe / N2 Supply System

- Performed quarterly and prior to startup following refueling 23

APS Responses to NRC Questions APS Responses to NRC Questions 24

APS Responses to Four Questions APS Responses to Four Questions

• Response to Question #4 (continued)

TS 5.5.8, Inservice Testing Program

- 2 Year Test Frequencies Specified by ASME OM Code

• Leak test (ISTC-3630)

- Palo Verde performs this test more frequently because credit is

• Response to Question #4 (continued)

TS 5.5.8, Inservice Testing Program

- 2 Year Test Frequencies Specified by ASME OM Code

• Leak test (ISTC-3630)

- Palo Verde performs this test more frequently because credit is taken for the quarterly closure verification of the check valves

• ADV Position Indication Test (ISTC-3700)

TS Surveillance Requirement (SR) 3.7.4.1

• Verify one complete cycle of each ADV every 18 months taken for the quarterly closure verification of the check valves

• ADV Position Indication Test (ISTC-3700)

TS Surveillance Requirement (SR) 3.7.4.1

• Verify one complete cycle of each ADV every 18 months 25

Summary Summary Q&A Q&A 26