ML20058M589
| ML20058M589 | |
| Person / Time | |
|---|---|
| Site: | Fermi, Saint Lucie, Crystal River, McGuire, LaSalle  |
| Issue date: | 09/27/1993 |
| From: | Chaffee A Office of Nuclear Reactor Regulation |
| To: | Grimes B Office of Nuclear Reactor Regulation |
| References | |
| OREM-93-036, OREM-93-36, NUDOCS 9310060242 | |
| Download: ML20058M589 (17) | |
Text
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September 27, 1993 MEMORANDUM FOR:
Brian K.
Grimes, Director Division of Operating Reactor Support FROM:
Alfred E.
Chaffee, Chief Events Assessment Branch Division of Operating Reactor Support
SUBJECT:
OPERATING REACTORS EVENTS BRIEFING SEPTEMBER 22, 1993 - BRIEFING 93-36 On September 22, 1993, we conducted an Operating Reactors Events Briefing (93-36) to inform senior managers from offices of the EDO, NRR, AEOD, RES, and regional offices of selected events that occurred since our last briefing on September 15, 1993. lists the attendees. presents the significant elements of the discussed events. contains reactor scram statistics for the week ending September 19, 1993.
No significant events were identified for input into the NRC Performance Indicator Program.
[ original signed by]
Alfred E.
Chaffee, Chief Events Assessment Branch Division of Operating Reactor Support
Enclosures:
As stated DISTRIBUTION:
TCentral-Files' cc w/ enclosures:
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T. Murley, NRR (12G18)
J.
Kennedy (PDIII-2)
F. Miraglia, NRR (12G18)
J.
Dyer (PDIII-2)
F.
Gillespie, NRR (12G18)
J. Wilcox (DRIL/RSIB)
J.
Partlow, NRR (12G18)
V. Nerses (PDII-3)
S.
Varga, NRR (14E4)
D. Matthews (PDII-3)
J.
Calvo, NRR (14A4)
G.
Lainas, NRR (14H3)
J.
Roe, NRR (13E4)
J.
Zwolinski, NRR (13H24)
E. Adensam, NRR (13E4)
W.
Russell, NRR (12G18) i J.
Wiggins, NRR (7D26)
A.
Thadani, NRR (8E2)
S.
Rosenberg, NRR (10E4)
C.
Rossi, NRR (9A2)
B.
Boger, NRR (10H3) 4 F.
Congel, NRR (10E2)
D.
Crutchfield, NRR (11H21)
W. Travers, NRR (11B19)
]
D.
Coe, ACRS (P-315)
E.
Jordan, AEOD (MN-3701)
G.
Holahan, AEOD (MN-9112)
L.
Spessard, AEOD (MN-3701)
K.
Brockman,-AEOD (MN-3206) i S.
Rubin, AEOD (MN-5219)
M. Harper, AEOD (MN-9112) i G.
Grant, EDO (17G21)
R.
Newlin, GPA (2GS)
E.
.i A.
Bates, SECY (16G15)
T. Martin, Region I l
W.
Kane, Region I l
R.
Cooper, Region I S.
Ebneter, Region II E. Merschoff, Region II S. Vias, Region II i
J. Martin, Region III E. Greenman, Region III J.
Milhoan, Region IV B.
Beach, Region IV B.
Faulkenberry, Region V K.
Perkins, Region V bec:
Mr. San Newton, Manager Events Analysis Departnent I
Institute of Nuclear Power Operations 700 Galleria Parkway Atlanta, GA 30339-5957 i
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UNITED STATES n
{s o,E NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555 o
/g September 27, 1993 i
MEMORANDUM FOR:
Brian K.
Grimes, Director Division of Operating Reactor Support FROM:
Alfred E.
Chaffee, Chief Events Assessment Branch Division of Operating Reactor Support
SUBJECT:
OPERATING REACTORS EVENTS BRIEFING SEPTEMBER 22, 1993 - BRIEFING 93-36 On September 22, 1993, we conducted an Operating Reactors Events Briefing (93-36) to inform senior managers from offices of the EDO, NRR, AEOD, RES, and regional offices of selected events that occurred since our last briefing on September 15, 1993. lists the attendees. presents the significant elements of the discussed events. contains reactor scram statistics for the week ending September 19, 1993.
No significant events were identified for input into the NRC Performance Indicator Program.
7 Al red E.
Chaffee, Chief Events Assessment Branch Division of Operating Reactor Support
Enclosures:
As stated cc w/ enclosures:
See next page
-e i
ENCLOSURE 1 LIST OF ATTENDEES OPERATING REACTORS EVENTS FULL BRIEFING (93-36)
SEPTEMBER 22, 1993 NAME OFFICE NAME OFFICE A. CHAFFEE NRR H.
CONRAD
YAMADA-NRR T. GREENE NRR V.
NERSES NRR J.
ZARZUELA NRR G.
CARUSO NRR-E.
BENNER NRR B.
SIEGEL NRR E. GOODWIN NRR L. MARSH NRR J.
CARTER NRR C.
ROSSI NRR B.
GRIMES NRR F. MIRAGLIA NRR J. WILCOX NRR J.
ROE NRR W.
ENG NRR S.
VARGA.
NRR M. VIRGILIO NRR A. RAMEY-SMITH OEDO S.
ROSENBERG NRR V.
BENAROYA AEOD K. KARWOSKI NRR W. MINNERS RES J.
STROSNIDER NRR TELEPHONE ATTENDANCE (AT ROLL CALL)
Recions Resident Inspectors Region I Region II Region III Region V IIT/AIT Team Leaders Misc.
e 9
i ENCLOSURE 2 l
.0PERATING REACTORS EVENTS BRIEFING 93-36 LOCATION:
10 B11, WHITE FLINT l
WEDNESDAY, SEPTEMBER 22, 1993, 11:00 A.M.
o LASALLE, UNIT'l LOSS OF STATION. AUXILIARY l
TRANSFORMER (AIT) r i
MCGUIRE, UNIT 1 SHUTDOWN FROM STEAM GENERATOR ~
TUBE LEAK
{
i PRESENTED BY:
EVENTS ASSESSMENT BRANCH DIVISION OF OPERATING' REACTOR-l SUPPORT, NRR t
=
.=
93-36 LASALLE, UNIT 1 LOSS OF STATION AUXILIARY TRANSFORMER SEPTEMBER 14, 1993 PROBLEM PLANT EXPERIENCED A LOSS OF 0FFSITE POWER.
CAUSE THE CAUSE WAS FAILURE OF STATION AUXILIARY TRANSFORMER (SAT).
SAFETY SIGNIFICANCE LOSS OF 0FFSITE POWER IS PRECURSOR TO A STATION BLACK 0UT EVENT.
DISCUSSION o
ON SEPTEMBER 14, 1993 WHILE AT 100% F0WER, LASALLE EXPERIENCED A REACTOR SCRAM DUE TO LOSS OF 0FFSITE POWER.
o UNIT 2 LOST SPENT FUEL P0OL COOLING.
o THE SAT TRIPPED DUE TO A BUS FAULT.
THE AFFECTED BUSES (152,141Y,142X, AND 142Y) FAST TRANSFERRED TO UNIT AUXILIARY TRANSFORMER (UAT).
o THE "B" TURBINE DRIVEN FEED PUMP CONTROL VALVE CLOSED AND THE REACTOR SCRAMMED ON LOW WATER LEVEL.
CONTACT:
T. GREENE, NRR/0EAB AIT:
YES
REFERENCE:
10 CFR 50.72 #26060 SIGEVENT:
TBD AND PN39352
LASALLE, UNIT 1 93-36 o
THE MAIN GENERATOR TRIPPED ON REVERSE CURRENT CAUSING LOSS OF REACTOR PROTECTION SYSTEM (RPS) BUSES AND UAT.
o ALL THREE EMERGENCY DIESELS GENERATORS STARTED AND LOADED BUSES 141Y AND 142Y.
o DECAY HEAT WAS REMOVED VIA THE SAFETY RELIEF VALVES (SRVs).
SEVERAL PROBLEMS WERE ENCOUNTERED WITH THE OPERATION OF THE SRVs.
o REACTOR CORE. ISOLATION COOLING WAS USED TO SUPPLY MAKEUP WATER AND TO HELP CONTROL PRESSURE.
THE HIGH PRESSURE CORE SPRAY ALSO WAS USED TO CONTROL PRESSURE.
o UNIT 1 EMERGENCY BUSES WERE CROSS-TIED TO UNIT 2 0FFSITE POWER AND 2 0F 3 EDGs PLACED IN STANDBY.
o THE MOTOR GENERATOR SET FOR RPS "B" BUS FAILED.
THIS FAILURE LOCKED-IN SEVERAL CONTAINMENT ISOLATION SIGNALS, SOME WHICH AFFECTED THE SHUTDOWN COOLING SUCTION SUPPLY VALVES FROM THE REACTOR COOLANT SYSTEM.
THEREFORE, NORMAL SHUTDOWN COOLING WAS UNAVAILABLE AND SUPPRESSION POOL COOLING STARTED.
o IT TOOK 29 HOURS TO BACK FEED THE NON-EMERGENCY BUSES VIA THE MAIN STARTUP TRANSFORMER BECAUSE THREE PROCEDURES WERE NEEDED.
o LICENSEE'S EMERGENCY OPERATING PROCEDURES REQUIRED LICENSEE DEPART FROM THEIR TECHNICAL SPECIFICATIONS AND THEREFORE MAKE A 10 CFR 50.54X REPORT.
LASALLE, UNIT 1 93-36 o
LICENSEE DECLARED AN ALERT IN ACCORDANCE WITH THE GENERAL STATION EMERGENCY PLAN.
o POWER WAS RESTORED TO THE "B" RPS BUS.
THE ISOLATION SIGNALS WERE RESET AND SHUTDOWN COOLING INITIATED.
FOLLOWUP o
CLOSURE OF TURBINE DRIVEN FEED PUMP CONTROL VALVE PROBABLY CAUSED BY FAST TRANSFER.
o AN AIT WAS SENT TO THE SITE ON SEPTEMBER 15, 1993.
TEAM LEADER IS J.D. WILC0X.
SOME PRELIMINARY FINDING ARE:
e THERE IS A PREVENTIVE MAINTENANCE PROBLEM.
e THE THREE PROCEDURES USED TO BACK FEED NEED TO BE INCORPORATED INTO ONE.
e THERE SEEMS TO BE A PROBLEM WITH CORRECTIVE ACTIONS BECAUSE LESSONS LEARNED FROM SIMILAR PREVIOUS EVENT NOT EMPLOYED.
e THERE IS A DESIGN PROBLEM WITH THE SAT.
e THERE WAS GOOD COMMUNICATION BETWEEN THE CONTROL STAFF AND THEIR MANAGEMENT.
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93-36 McGUIRE, UNIT 1 SHUTDOWN FROM STEAM GENERATOR TUBE LEAK AUGUST 21, 1993 PROBLEM STEAM GENERATOR (SG) TUBE LEAK OF 176 GALLONS PER DAY (GPD)
CAUSE CIRCUMFERENTIAL SG TUBE CRACK AB0VE SLEEVE JOINT SAFETY SIGNIFICANCE SG TUBE LEAKS MAY BE PRECURSORS TO SG TUBE RUPTURES DISCUSSION AUGUST 21:
UNIT AT 100% POWER 2250:
RADIATION ALARMS FROM STEAM LINE NITROGEN-16 AND CONDENSER EJECTOR RAD MONITORS I
AUGUST 22:
0036:
CHEMISTRY SAMPLES ANALYZED INDICATED SG "A" HAD A LEAK 0F 176 GPD (TECH SPEC LIMIT 500 GPD THROUGH ANY ONE SG)
BASED ON INTERNAL ADMINISTRATIVE LIMITS (50 GPD THROUGH ANY ONE SG) SHUTDOWN COMMENCED CONTACT:
J. ZARZUELA, NRR/0EAB AIT:
NO
REFERENCE:
PN29338 SIGEVENT: TBD
MCGUIRE, UNIT 1 93-36 0521:
REACTOR SHUTDOWN 0635:
C00LDOWN AND DEPRESSURIZATION COMMENCED IN ACCORDANCE WITH ABNORMAL PROCEDURE LICENSEE PERFORMED PRESSURE TEST AT 530 PSI IN SECONDARY SIDE AND FOUND:
LEAK
- LEAKING SG (GPD)
TUBES TYPE OF DEFECT A
185 4
3X 1Y B
15 3
2X 1Z C
0 0
D 2
1 1X 8
6 1
1 X:
SMALL LEAKS THROUGH UPPER JOINT OF SLEEVED TUBE (H0T LEG).
Y:
TUBE 39-72 0F SG "A"; RESPONSIBLE FOR THE LEAK THAT LED TO PLANT SHUTDOWN.
CIRCUMFERENTIAL CRACK (120
- 180 ) AB0VE SLEEVE JOINT.
Z:
TUBE 41-43 0F SG "B"; 75* CIRCUMFERENTIAL CRACK IN THE U-BEND, COLD LEG, ABOUT 6" AB0VE THE TANGENT.
O MCGUIRE, UNIT 1 93-36 DEFECTS TYPE X ALL SIX TUBES WITH LEAKS THROUGH UPPER WELD WERE SLEEVED IN 1990 OUTAGE.
396 MORE TUBES SLEEVED DURING THAT OUTAGE.
CLEANING PROCESS FOR TUBE SURFACE WAS IMPROVED FOLLOWING 1990 OUTAGE.
DEFECTS TYPE Y TWO TUBES PULLED AND ANALYZED: 39-72 0F SG "A" AND ANOTHER ONE FOR REFERENCE.
LICENSEE ASSERTS TUBE 39-72 0F SG "A" FAILED BECAUSE IT WAS MORE SUSCEPTIBLE TO PWSCC THAN TYPICAL, THEREFORE STANDARD STRESS RELIEF HEAT TREATMENT AFTER SLEEVING NOT ADEQUATE.
QUALIFICATION OF HEAT TREATMENT PROCEDURE WAS CORRECT FOR NORMAL TUBES, BUT THE TUBE WAS AN OUTLIER IN MATERIAL PROPERTIES (VERY HIGH YIELD STRENGTH).
THIS RAISES GENERIC QUESTION AS TO W!! ETHER SLEEVING STRESS RELIEF PROCEDURE WAS ADEQUATE FOR ACTUAL TUBE POPULATION.
LICENSEE TO SHUT DOWN UNIT 2 BY EARLY OCTOBER AFTER CONNECTING UNIT 1 TO GRID, IN ORDER TO PLUG ANY TUBE SUSCEPTIBLE TO THE PHENOMENON AFFECTING 39-72 IN SG "A" UNIT 1.
MCGUIRE, UNIT 1 93-36 DEFECTS TYPE Z DURING APRIL 1993 OUTAGE, THE CIRCUMFERENTIAL CRACK IN THE U-BEND WAS NOT DETECTED.
REVIEWING THOSE APRIL 1993 RECORDS, LICENSEE CONCLUDED THAT INDICATIONS SHOULD HAVE TRIGGERED ADDITIONAL EXAMINATION.
CONSERVATIVELY ASSESSING P0TENTIAL FOR OTHER CRACKS LIKE THE MISSED ONE IN TUBE 41-43 0F SG "B",
LICENSEE HAS IDENTIFIED 31 NON-CRACK LIKE INDICATIONS THAT WILL BE PLUGGED.
FOLLOW UP LICENSEE PLUGGING TUBES IN UNIT 1; PREPARING INSPECTION PROGRAM FOR UNIT 2 B&W TO CONTACT OTHER LICENSEES P0TENTIALLY AFFECTED BY THIS PROBLEM REGION II AND NRR CLOSELY FOLLOWING INSPECTION RESULTS MATERIALS AND CHEMICAL ENGINEERING BRANCH CONSIDERING NEED FOR AN INFORMATION NOTICE
McGuire, Unit 1 Briefing 93-36 TUBE / SLEEVE QRIENTATION I
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- i
i ENCLOSURE'3-
)
REACTOR SCRAM I
.e i
Reporting Period: 09/13/93 to 09/19/93
[
YTD YTD ABOVE -
BELOW YTD
'E!!1 PLANT 8 UWIT
]5MS 11!1 CAlfSI CPPLICATIONS
.M3 Ill..
IQIAL 09/13/93 GRAND GULF 1 100 SA Other to 1-0' 1:
09/14/93 LASALLE 1 100 SA Ecpipment Felture to 3
0 3
i 09/17/93 FERMI 2 17 Set E gipment Falture no 3
1 4
?
09/18/93-SAINT LUCIE 1 75 5 84 External NO 1
0 1
09/18/93 CRYSTAL RIVER 3 100 SA E wipment failure no 1
0
- 1 i
6 i
.t h
i i
i 1
i
.. j i
I t
- Ostes Year To Date (Yt9) Totsis include Events Within Yhe talender Year Irsficated By The End Date of The specified soporting Period ETS-10 p*8'1 09/21/93 i
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^
c COMPARISDN OF WEEKLY SCRAM STATISTICS WITH INDUSTRY AVERAGES PERICD ENDING 09/19/93 t
trJesER 1993 1992 1991*
1990*
1989*
OF WEERY WEERY WEEKLY WEENY WEnY SCRAM CAUSE-SCRAMS AVERAGE AVERAGE AVERAGE AVERAGE-AVERAGE (YTD)
PotAR GREATER ThAN OR EQUAL TO 15%
EQUIPMENT FAILURE
- 3 1.8 2.6 2.9 3.4 3.1 DESIGN / INSTALLATION ERROR
- O 0.1 CPERAflWG ERROR
- 0 0.3 0.2 0.6 0.5 1.0 MINTENANCE ERROR
- 0 0.6 0.4 EXTERNAL
- 1 0.1 OTHER*
1 0.0 0.2 0.1 S stotet 5
2.9 3.4 3.5 3.9 4.2 l
POWER LESS TNAN 15%
l EQUIPMENT FAILURE
- 0' O.3 0.4 0.3 0.4 0.3 DESIGN / INSTALLATION ERROR
- 0 0.0 OPERATING ERROR
- O 0.2 0.1 0.2 0.1 0.3 MAINTENANCE ERROR
- O 0.0 0.1 EXTERNAL
- 0 0.0 CTHER*
0 0.0 0.1 S@totet 0
0.5 0.7 0.5 0.5 0.6 i
TOTAL 5
3.4 4.1 4.0 4.4 4.8 i
I e
1993 1992 1991 1990 1989 i
Wo. OF WEE nY WEENY WEERY WEENY EERY SCRAM TYPE SC3 TAMS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE i
(YTC)
TOTAL AUTouTIC SCRAMS 3-2.6 3.1 3.3 3.2 3.9 l
TOTAL MANUAL SCRAMS 2
0.9 1.0 0.7 1.2 0.9 l
1 TOTALS MAY DlFFER SECAUSE OF ROUNDING OFF
- Detailed breakdown ret in detsbese for 1991 and earlier I
- EXTERNAL coise included in EQUIPMENT FAILURE 7
MAINTENANCE ERROR and DESIGN / INSTALLATION ERROR causes inchssed in OPERATING ERROR
{
- OTHER cause Incha$ed in EQUIPMENT FAILURE 1991 and 1990 i
5 ETS.14 Peper 1 09/21/93
}
m n,
r NOTES
- 1.
PLANT SPECIFIC DATA BASED ON INITIAL REVIEW OF 50.72 REPORTS FOR THE WEEK OF INTEREST.
PERIOD IS MIDNIGHT SUNDAY THROUGH MIDNIGHT SUNDAY.
SCRAMS ARE DEFINED AS REACTOR PROTECTIVE ACTUATIONS WHICH RESULT IN ROD MOTION, AND EXCLUDE PLANNED TESTS OR SCRAMS AS PART OF PLANNED SHUTDOWN IN ACCORDANCE WITH A PLANT PROCEDURE.
THERE ARE 111 REACTORS HOLDING AN OPERATING LICENSE.
2.
PERSONELL RELATED PROBLEMS INCLUDE HUMAN ERROR, PROCEDURAL DEFICIENCIES, AND MANUAL STEAM GENERATOR LEVEL CONTROL PROBLEMS.
3.
COMPLICATIONS: RECOVERY COMPLICATED B'I EQUIPMENT FAILURES OR PERSONNEL ERRORS UNRELATED TO CAUSE OF SCRAM.
4.
"OTHER" INCLUDES AUTOMATIC SCRAMS ATTRIBUTED TO ENVIRONMENTAL CAUSES (LIGHTNING), SYSTEM DESIGN, OR UNKNOWN CAUSE.
OEAB SCRAM DATA Manual and Automatic Scrams for 1987 ------------------ 435 Manual and Automatic Scrams for 1988 ------------------ 291 Manual and Automatic Scrams for 1989 ------------------ 252 Manual and Automatic Scrams for 1990 ------------------ 226 Manual and Automatic Scrams for 1991 ------------------ 206 i
Manual and Automatic Scrams for 1992 ------------------ 212 Manual and Automatic Scrams for 1993 --(YTD 09/19/93)-- 131 i
1 l
,