ML13197A095
| ML13197A095 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 07/11/2013 |
| From: | Arizona Public Service Co |
| To: | Division of Operating Reactor Licensing |
| Rankin J | |
| References | |
| TAC MF1932, TAC MF1933, TAC MF1934 | |
| Download: ML13197A095 (23) | |
Text
Implementation of STAR Program and Replacement of the 2/3 Cycle MTC Measurement Pre-Submittal Presentation to the NRC Date: 07/11/2013
Purpose
- Present and discuss with the NRC planned licensing changes
- Implementation of the Startup Testing Activity Reduction (STAR) Program at PVNGS
- Replacement of the 2/3 Cycle Moderator Temperature Coefficient (MTC) Measurement 2
Topics
- Replacement of the 2/3 Cycle MTC Measurement
- Licensing Approach
- Conclusion and Discussion 3
- Objectives
- Alternate method to validate core design
- Minimize the time the plant is in an abnormal configuration 4
- Overview
- Approved by NRC in WCAP-16011-P-A
- Participating plants only
- Successfully implemented at 8 CE units
- Incorporated into Improved Standard TS
- NUREG-1432, Rev 4
- TSTF 486 5
- Overview
- Adds
- Credits Pre-Operational Checks
- New Beginning of Cycle (BOC) Hot Zero Power (HZP) MTC surveillance methodology
- Applicability Requirements
- Replaces
- CEA Worth Measurement 6
- Current Methodology
- CEA worth measurement
- Require operation outside the normal TS LCOs
- Presents operational challenges
- Unit 3 LER 2012-001
- Unit 1 LER 2011-005
- Measure ITC at HZP with use of reactivity computer 7
- Proposed Methodology
- Replacement of CEA Worth Measurements
- Use applicability requirements
- Replacement will reduce the occurrence of problems associated with testing and minimize time in abnormal operating configuration 8
- Proposed Methodology (cont.)
- Alternate MTC verification
- Adjust predicted HZP MTC based on measured Critical Boron
- Increase availability of the control channels
- Align PVNGS with Improved Standard TS 9
- Applicability Requirements
- Found in Table 3-4 of WCAP-16011-P-A
- Compliance evaluated on a reload cycle-specific basis
- STAR only applied to cycles when compliance verified
- Maintain the effectiveness of the STAR Program in problem identification 10
- Applicability Requirements (cont.)
- Core design methods have a defined set of uncertainties based on a benchmark of predictions to actual plant measurements
- Core, fuel, CEA design are similar to that of a benchmarked core
- Cycle specific predictions independently verified by
- Comparison of 2 independent neutronics codes 11
- Applicability Requirements (cont.)
- Implementation of CEA Lifetime Program
- Limit CEA life within operation experience base
- Pre-operational checks verify core and CEA loading are consistent with design
- CEA Coupling checks performed during reactor restack
- Many favorable PVNGS unique design feature 12
- Benefits
- Minimize the time the plant is in an abnormal operating configuration
- Increase the availability of the control channels
- Operationally focused improvement 13
- WCAP 16011-P-A approach
- Compare STAR Program to Generic Program
- Generic Program based on ANSI/ANS 19.6.1-1997
- Identify set of core problems
- Design Predictions
- As-Built Core
- Test Performance 14
- WCAP 16011-P-A approach (cont.)
- Concluded STAR Program is as effective in detecting the Problems as the Generic Program
- STAR is an NRC approved and implemented alternative to current testing methodology.
15
- PVNGS Application
- Compared
- Design differences between PVNGS and original participating plants
- Differences in current PVNGS startup program and Generic Program
- Operating Experience since original STAR
- NRC and INPO
- PVNGS
- Implementing plants 16
- Results of Evaluations
- Contained in plant specific justification
- CASMO/SIMULATE as applied at PVNGS is acceptable for STAR
- The PVNGS STAR Program is as effective as the approved STAR Program and is an acceptable alternative to the current PVNGS startup testing program.
17
Replacement of 2/3 Cycle MTC Measurement
- Objective
- To replace the 2/3 cycle MTC measurement with alternate verification
- Overview
- Approved for all CE plants in CE NPSD-911-A and Amendment 1-A (TSTF 406)
- No measurement at 2/3 cycle if 40 EFPD measurement is within acceptance criteria
- Already implemented at many PWRs 18
Replacement of 2/3 Cycle MTC Measurement
- Current Topical only applicable for ROCS
& ANC
- PVNGS will demonstrate applicability of SIMULATE
- Conclusions
- SIMULATE is acceptable for use
- Replacement of the 2/3 cycle MTC measurement is acceptable at PVNGS including STAR Cycles 19
Licensing Approach
- Submit one LAR
- Application of STAR to PVNGS
- Replacement of 2/3 cycle MTC Measurement 20
Licensing Approach
- SR 3.1.4.1 (HZP verification)
- SR 3.1.4.2 (At power verifications)
- Add note allowing replacement of 2/3 cycle at power MTC Measurement (CE-NPSD-911 & TSTF 406) 21
Licensing Approach
- Proposed Schedule
- Submit November 2013
- Requesting NRC Approval in November 2014
- First use in Spring of 2015 22
Conclusion and Discussion
- Acceptable to replace the 2/3 cycle at power MTC measurement
- Submit both under a single LAR November 2013
- Requesting NRC approval November 2014 23