ML14219A476
| ML14219A476 | |
| Person / Time | |
|---|---|
| Site: | Summer, Vogtle  |
| Issue date: | 08/07/2014 |
| From: | Laura R NRC/NRO/DCIP/CQAB |
| To: | |
| Laura R | |
| References | |
| Download: ML14219A476 (21) | |
Text
Ope ating E pe ience Operating Experience 8/7/2014 1
OpE shows Initial Testing Important to...
V if l
b il d
i d
lid d
i Verify plant built as designed, validate design Identify inadequacies, adverse system interactions.
OpE for Initial Testing is considered because...
R l
i DCD Regulatory commitments - DCD Experiences from Part 50 Plant Startup d
l Industry Operating Lessons - Plant Events 8/7/2014 2
Design Control Document Section 14.2.5, Rev 19 Utili ti f R t
O ti
& St t
E i
i Utilization of Reactor Operating & Startup Experience in Development of Test Program Past PWR Operating Experience & Testing Experience Used to Develop Initial Test Program Other Sources of OpE Used in AP1000 ITP Question: How is this being done for Vogtle?
Summer?
Summer?
8/7/2014 3
Safety Culture in Pre-operational Phases of Nuclear P
Pl P
j d
d Power Plant Projects dated 2012 Source: IAEA Safety Report Series - # 74
(
)
(Publication 1555)
Safety culture includes questioning attitude, i
i l l i
i h
organizational learning, proactive approach Operating Experience is important component of O
i ti l L i
Organizational Learning Proper safety perspective for Initial Testing - one that proves SSCs are functional that proves SSCs are functional 8/7/2014 4
INTERNATIONAL 2011 European Summary Report on Construction and Commissioning p
y p
g International reporting System (IRS) - Web Search 18 hits DOMESTIC NRC Circulars & Information Notices - 16 hits NRC Licensee Event Reports LERs - 155 hits NUREG 1055 Improving Quality in Design / Construction of NPPs, 1984 NUREG V l IRS S R
NUREG-1275 Volume 1 - IRS Summary Report NUREG-0969, Zimmer Project, 1983 INDUSTRY INDUSTRY INPO Documents and References - SOERs, SERs WEB SEARCHES 8/7/2014 5
WEB SEARCHES Industry, Domestic, International
Preoperational Testing Lessons Learned p
g Adequate Planning for Preoperational Test execution Plan Transition from Construction to Testing System & Organizational Turnover System & Organizational Turnover Adequate Test Procedure Quality assures Adequate Test Procedure Quality assures Fidelity between Preoperational/Startup Tests and Design Basis Documents - DCDs FSAR g
8/7/2014 6
Preoperational Testing Lessons Learned Preoperational Testing Lessons Learned F
ti l t ti i fi l b i
t l
Functional testing is final barrier to reveal construction deficiencies resulting in SSCs bl t f
d i
f ti unable to perform design function 8/7/2014 7
European Commission Joint Research Center S
R t
N l
P Pl t C t
ti Summary Report on Nuclear Power Plants Construction, Commissioning and Manufacturing Events, 2011 Analysis to identify events from construction and commissioning of NPPs Three sources of information NRC Licensee Event Reports (LERs)- 309 LERs applicable Incident Reporting S stem (IRS) 24 reports applicable Incident Reporting System (IRS)-247 reports applicable Working Group on Regulation for New Reactors (WGRNR)
- 26 WGRNR events were applicable to study 8/7/2014 8
European Commission Joint Research Center S
R t M j C
l i
Summary Report Major Conclusions Items most affected by construction or commissioning deviations are I&C (19%), electrical components (17%),
welds (14%), valves (10%) and pipes (9%).
Average detection time of the initial defect is about 8 years after the start of commercial operation.
Common cause failures can be high for some materials:
more than 50 % for civil work and fire protection, 45 % for 8/7/2014 9
electrical components (the average is 34 %)
International Lessons Learned...
E C
i i
J i t R h C t
European Commission Joint Research Center Summary Report Major Conclusions More than 75 % of the events are found fortuitously, and the rate of detection is particularly high for civil work, electrical components I&C pipes and valves electrical components, I&C, pipes and valves.
Some items such as civil work (structure, anchorages,
)
d l i
l hibi ll h supports) and electrical components exhibit all three: a long detection time, a high rate of common cause failure and a high rate of fortuitous detection.
8/7/2014 10 g
International Lessons Learned...
E C
i i
J i t R h C t
European Commission Joint Research Center Summary Report Major Conclusions The conclusions emphasize the need to minimize the number of deficiencies during construction manufacturing and of deficiencies during construction, manufacturing and commissioning of a new reactor, as they can be major latent failures for a long time and can have safety consequences fafter reactors start to operate.
8/7/2014 11
Inadequate Pre-Operational Testing Results in Plant q
p g
Operation with SSCs not functioning per design BWR: HPCI/RCIC flow not calibrated correctly since startup LER 353/2-2007-03 PWR: Protection Instrument Calibration Graphs inadequate since startup LER 305/2009-06 8/7/2014 12
Inadequate Pre-Operational Testing Results in Plant q
p g
Operation with SSCs not functioning per design PWR: Inadequate PMT of frequency relay setting results in dual unit loss of offsite power LER 413/2012-01 BWR: wiring errors in EDG control logic circuit results in inability to locally operate EDG from the Safe Shutdown Panel LER 324/2008-06 8/7/2014 13
OpE Shows Effective Preoperational Testing Important to...
Identify unrecognized Intersystem Dependencies Identify Single Point Vulnerabilities Avoid Unwanted Consequences Plant events - domestic & foreign (next slides) g
(
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Scrams with complications Multiple train failures Increases in Core Damage Frequency Increases in Core Damage Frequency 8/7/2014 14
Reactor Transients, LOOPS and Scrams with Complications Recent nuclear plants events involve examples where multiple trains of equipment were affected by single event or common cause failure Other significant events involve the common cause failure of non-Other significant events involve the common cause failure of non safety related electrical equipment h
d h
l f l d
h ld The events provide insights on potential failure modes that could be avoided with proper attention to design and testing during the construction and initial testing phases 8/7/2014 15
Reactor Transients, LOOPS and Scrams with Complications Complications BWR Dual Unit Scram & LOOP 2013 D fi i l
i l
i i
h i
h d
di Deficient electrical connections in the switchyard grounding system due to poor workmanship existing since original construction LER 373/2013-02 BWR Scram with Complications 2013 P
t difi ti t
ti h
ld id tif i
l i t Proper post modification testing should identify single point vulnerability in non-safety systems that impacts plant safety LER 293/2013-01 8/7/2014 16
Reactor Transients, LOOPS and Scrams with Complications Complications Foreign BWR Scram, LOOP & Complicated LOOP 2006 g
p Preoperational testing should identify EDS design vulnerabilities such as proper phase connections of protection relays. IN 2006-18.
y PWR Scram, 345kV Open Phase & Fault 2012 Preoperational testing should verify design of the under-voltage protection intended to identify degraded grid conditions LER 454/2012-01 8/7/2014 17
Four Recent Significant Events Highlight that...
Pl t
t d b i
l i t Plant events are caused by single point vulnerabilities & common mode failures Events result from design errors, inadequate design modifications and reviews, and g
inadequate work control or work practices Events caused by unrecognized workmanship or installation errors from original construction.
8/7/2014 18
Four Recent Significant Events highlight that...
Functional testing is the final barrier to reveal construction deficiencies construction deficiencies Robust and comprehensive test program can p
p g
identify design and installation deficiencies Proper consideration of Operational Experience helps assure Initial Testing is effective 8/7/2014 19
Q ti
?
Questions?
8/7/2014 20
NRC Inspection Procedures for New NRC Inspection Procedures for New Reactor Plant Initial Test Programs
- IP 70367, Part 52, Inspection of Preoperational Test Program
- IP 70702, Inspection of Preoperational Test 0 0,
spect o o
eope at o a est Program Performance
- NRC AP1000 Preoperational Test Program Inspection Planning Tool Inspection Planning Tool
T ti f
th AP1000 T t
- IP 72304, Startup Testing for the AP1000, Test Procedure Review, Test Witnessing and Test Results Evaluation (under final review for issuance) issuance)