ML20029C796
| ML20029C796 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde, Grand Gulf, South Texas  |
| Issue date: | 04/04/1994 |
| From: | Chaffee A Office of Nuclear Reactor Regulation |
| To: | Grimes B Office of Nuclear Reactor Regulation |
| References | |
| OREM-94-011, OREM-94-11, NUDOCS 9404290187 | |
| Download: ML20029C796 (19) | |
Text
April 4, 1994 j
6 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 MARCH 23, 1994 - BRIEFING 94-11 on March 23, 1994, we conducted an Operating Reactors Events Briefing (94-11) to inform senior managers from offices of the Commission, AEOD, RES, EDO, NRR, and regional offices of selected events that occurred since our last briefing on March 9, 1994. lists the attendees. presents the significant elements of the discussed events. contains reactor scram statistics for the week'ending March 13, 1994.
There were no scrams reported for week ending March 20, 1994.
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 cc w/ enclosures:
See next page DISTRIBUTION:
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W. Russell, NRR (12G18)
T. Polich (PDV)
F. Miraglia, NRR (12G18)
T.
Quay (PDV)
F. Gillespie, NRR (12G18)
P. O'Connor (PDIV-1)
Acting ADPR, NRR (12G18)
W. Beckner (PDIV-1)
S. Varga, NRR (14E4)
L.
Kokajko (PDIV-2)
J.
Calvo, NRR (14A4)
S. Black (PDIV-2)
G.
Lainas, NRR (14H3)
J. Roe, NRR (13E4)
J.
Zwolinski, NRR (13H24)
E. Adensam, NRR (13E4)
A. Thadani, NRR (12G18)
B.
Sheron, NRR (7D26)
M. Virgilio, NRR (BE2)
S.
Rosenoerg, NRR (10E4)
C.
Rossi, NRR (9A2)
B.
Boger, NRR (10H3)
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)
S. Rubin, AEOD (MN-5219)
M. Harper, AEOD (MN-9112)
W.
Bateman, EDO (17G21)
F. Ingram, PA (2G5)
A. Bates, SECY (16G15)
T. Martin, Region I R.
Cooper, Region I S.
Ebneter, Region II J. Johnson, Region II S. Vias, Region II J.
Martin, Region III E. Greenman, Region III L. Callan, Region IV A. Beach, Region IV K. Perkins, Region V S.
Richards, Region V bec:
Mr. Sam Newton, Manager Events Analysis Department Institute of Nuclear Power Operations 700 Galleria Parkway Atlanta, GA 30339-5957
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UNITED STATES.
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NUCLEAR REGULATORY COMMISSION I
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April 4, 1994 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 MARCH 23, 1994 - BRIEFING 94-11 On March 23, 1994, we conducted an Operating Reactors Events Briefing (94-11) to inform senior managers.from offices-of the Commission, AEOD, RES, EDO, NRR, and regional offices of selected events that occurred since our last briefing on March 9, 1994. lists the attendees. presents the significant elements of the discussed events. contains reactor scram statistics for the week ending.
March 13, 1994.
There were no scrams reported for week ending March 20, 1994.
No significant events were identified for input into the NRC Performance Indicator Program.
b' Alfred E. Chaffee, Chief Events Assessment Branch Division of Operating Reactor Support
Enclosures:
As stated cc w/ enclosures:
See next page
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ENCLOSURE 1 LIST OF ATTENDEES OPERATING REACTORS EVENTS FULL BRIEFING '(94-11)
MARCH 23, 1994 NAME OFFICE NAME OFFICE A.
CHAFFEE NRR E. ADENSAM NRR R. BENEDICT NRR C. THOMAS NRR D. SKEEN NRR C.
ROSSI NRR T. KOSHY NRR B. GRIMES NRR R. DENNIG NRR L. REYES-NRR T. YAMADA NRR S. VARGA NRR A.
BYRDSONG NRR J. ROE NRR-B.
HOLIAN NRR D.
LONG NRR S.
BL.CK NRR L. KOKAJKO NRR R. ECKENRODE NRR-M.
SLOSSON NRR K. ECCLESTON NRR D.
TATUM OEDO C. MAYBERRY NRR G.
HOLAHAN AEOD P. O'CONNOR NRR M. RUBIN.
OCM/IS G. DICK NRR J. SORENSEN OCM/KR L. TRAN NRR F. CHERNY RES G. HAMMER NRR C.
HRABAL RES-TELEPHONE ATTENDANCE (AT ROLL CALL)
Recions Resident Insoectors Region I Palo Verde Region II Grand ~ Gulf Region III Region IV Region V IIT/AIT Team Leaders Misc.
M. Wegner, AEOD-
)
i
76f
. ENCLOSURE 2'-
t OPERATING REACTORS EVENTS BRIEFING 94-11 LOCATION:
10 Bil, WHITE FLINT WEDNESDAY, MARCH 23, 1994'11:00 A.M.
PALO VERDE, SAFETY VALVE SETPOINT UNIT 1 TEST METHODS
- GRAND GULF STANDBY SERVICE WATER PUMP POTENTIAL COMMON CAUSE. FAILURE SOUTH TEXAS, DEFICIENT SURVEILLANCE OF l
UNITS 1 & 2 CONTROL ROOM AIR DAMPERS q
i i
1 PRESENTED BY:
EVENTS ASSESSMENT. BRANCH DIVISION 0FLOPERATING REACTOR 4
SUPPORT, NRR t
+-
]
94-11 PALO VERDE, UNIT 1 SAFETY VALVE SETPOINT TEST METHODS SEPTEMBER 14, 1993 PROBLEM MAIN STEAM SAFETY VALVES (MSSV) DECLARED IN0PERABLE.
CAUSE VALVE SETPOINTS DETERMINED TO BE OUTSIDE 1% TECHNICAL SPECIFICATION LIMIT.
SAFETY SIGNIFICANCE VALVE MIGHT BE ADJUSTED SUCH THAT ITS SETPOINT IS T00 HIGH.
DISCUSSION o
PALO VERDE HAS USFO TWO METHODS TO TEST VALVE SETPOINTS:
e LIVE STEAM AT OFFSITE TEST FACILITY (ACTUAL STEAM PRESSURE) e "TREVITEST" BY FURMANITE AMERICA INC.
(STEM PULLED MECHANICALLY) o LAST OUTAGE ALL MSSVs WERE TESTED, REFURBISHED AND SET AT WESTINGHOUSE LIVE STEAM TEST FACILITY.
VALVES THEN INSTALLED AT PALO VERDE AND OPERATED ONE CYCLE.
CONTACT:
R. BENEDICT, NRR/ DOR 3 AIT: TBD
REFERENCE:
MORNING REPORT #5-93-0063, SIGEVENT: TBD DATED 09/14/93 s-
94-11 J-
' PALO VERDE,. UNIT 1-2-
l IN AUGUST 1993, TREVITESTINGLINDICATED 8 0F 9 VALVES L
e l
L
- TESTED FAILED TO MEET.THE TECHNICAL SPECIFICATION LIMIT L
OF 1%.
THE READINGS VARIED FROM 1.8 TO 5.4 PERCENT LOW.
j e
TESTING WAS SUSPENDED.
1 THREE MORE PREVIOUSLY LIVE-STEAM-TESTED VALVES'WERE RE--
TESTED ON BOTH LIVE STEAM AND TREVITEST.
. RESULTS SHOWED A CONSISTENT OFFSET IN SETPOINT BETWEEN THE.TWO TEST METHODS.
ADDITIONAL TESTS SHOWED TREVITEST SETPOINTS GENERALLY e
LOWER THAN-LIVE STEAM SETPOINTS.
TREVITEST DETERMINES THE LIFT PRESSURE SETPOINT BY e
RELATING THE FORCE REQUIRED TO OPEN THE VALVE TO THE.
LIFT PRESSURE.
THE. AREA OVER WHICH THE-FORCE ACTSTIS q
NOMINALLY THE MEAN SEAT AREA-(MSA).
THE MSA IS USED TOl j
CONVERT THE LIFT FORCE T0 LIFT PRESSURE.
TREVITEST ASSUMED MSA BASED ON AVERAGE OF SEATLINNER AND OUTER DIAMETERS PER VALVE DESIGN.
THE RESULTING i
CALCULATED LIFT PRESSURE WAS LOW.
AS A RESULT, VALVES 1
READJUSTED USING TREVITEST MAY BE SET T00 HIGH DUE TO THIS ERROR.
1 THE MSA USED IN THE TREVITEST METHOD HAS BEEN ADJUSTED,-
)
e BASED ON COMPARATIVE TEST DATA, TO MINIMIZE SETPOINY 0FFSET.
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PALO VERDE, UNIT 1 94-11 o-THIS ADJUSTMENT APPLIES ONLY TO DRESSER / CONSOLIDATED MODEL 3707R VALVE.
OTHER MODELS NOT ADDRESSED.
FURMANITE NOTIFIED THE FOLLOWING LICENSEES ABOUT THE o
MSA ADJUSTMENT NEEDED FOR TREVITEST.
ALSO SENT LETTER TO NRC MARCH 16, 1994.
BYRON /BRAIDWOOD SURRY SOUTH TEXAS PROJECT DC. COOK FORT CALHOUN DIABLO CANYON FARLEY PALO VERDE t
SOME PLANTS DECLARED VALVES INOPERABLE AND REQUESTED e
ENFORCEMENT DISCRETION UNTIL VALVES CAN BE RESET.
F0LLOWUP REGION V REQUESTED TECHNICAL ASSISTANCE BY NRR TO EVALUATE DIFFERENCES IN TEST METHODS AND DETERMINE GENERIC ISSUES.
STAFF ALSO DETERMINING APPLICABILITY TO OTHER e
DRESSER / CONSOLIDATED VALVE MODELS AND TO CROSBY VALVES.
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94-GRAND GULF STANDBY SERVICE WATER. PUMP POTENTIAL COMMON CAUSE FAILURE MARCH 11, 1994 PROBLEM THE "B" STANDBY SERVICE WATER (SSW) PUMP SHAFT SLIPPED, i
CAUSING DAMAGE TO THE FIRST AND SECOND STAGE IMPELLERS.AND' 1
BOWLS.
l CAUSE CORROSION OF COUPLING BOLTS AND LOCK WASHERS ALLOWED SHAFT SEGMENTS TO SLIP.
SAFETY SIGNIFICANCE q
POTENTIAL COMMON CAUSE FAILURE OF A SAFETY RELATED SUPPORT SYSTEM.
DISCUSSION 1
e 03/03/94 - VIBRATION MEASUREMENTS WERE TAKEN DURING WEEKLY RUN OF "B" SSW PUMP DUE TO SUSPECTED SEAL LEAKAGE.
READINGS WERE DIFFERENT FROM BASELINE, S0 MORE MEASUREMENTS WERE TAKEN THROUGHOUT THE MORNING.
VIBRATION READINGS GOT PROGRESSIVELY WORSE AND THE PUMP e
WAS TAKEN OUT OF SERVICE TO TROUBLESHOOT.
COUPLING BOLTS AND LOCK WASHERS WERE FOUND CORRODED SUCH THAT THE IMPELLERS HAD DROPPED MORE THAN ONE INCH FROM THEIR PRESET POSITION, ALLOWING THEM T0.COME IN CONTACT WITH THE B0WLS.
CONTACT:
D. SKEEN, NRR/ DORS AIT: _HQ
REFERENCE:
10 CFR-50.72'#26921 SIGEVENT: IRQ L
..m.
-,,,,,,.,7
LGRAND' GULF 94-11 o'
AT LEASTl1 INCH OF METAL HAD BEEN WORN.AWAY FROM THE L
IMPELLERS AND BOWLS.
o THE "B" PUMP WAS REASSEMBLED USING SPARE IMPELLERS, BOWLS AND FASTENERS, AND RETURNED TO SERVICE ON 03/08/94.
a o
03/10/94 - THE "A" PUMP WAS REMOVED FROM SERVICE AND INSPECTED.
SIMILAR BUT LESS SEVERE CORROSION WAS FOUND 1
ON THE COUPLING BOLTS AND LOCKWASHERS.
1 o
THE IMPELLERS AND BOWLS OF THE "A" PUMP WERE JUST BEGINNING TO SHOW SIGNS OF WEAR (LESS-THAN 1/16 INCH).
o THE "A" PUMP WAS REASSEMBLED USING NEW BOLTING HARDWARE AND RETURNED TO SERVICE WITHIN 72 HOURS.
)
FOLLOWUP j
e QUARTERLY INSERVICE TESTING OF THE SSW PUMPS DID NOT l
DETECT THE PROBLEMS WITH THE IMPELLERS.
j AT.LEAST TWO OPPORTUNITIES TO IDENTIFY THE PROBLEM WITH e
THE "B" PUMP SHAFT WERE MISSED WHEN THE SHAFT WAS LIFT-CHECKED DURING REFUEL OUTAGES (RFO) 4 AND 6.
R e
SLIGHTLY HIGH VIBRATIONS WERE DETECTED DURING RFO 6 TESTING.
THE LIFT WAS RESET AND THE VIBRATIONS CEASED.
NO MAINTENANCE REQUIREMENT FOR REMOVAL AND INSPECTION OF THE PUMP SHAFT AND IMPELLERS EXISTED.
QUARTERLY 1
TESTING PER ASME CODE WAS BELIEVED TO'BE SUFFICIENT.
i 4
GRAND GULF 94.,
- o REGION II IS DRAFTING AN INFORMATION NOTICE TO ALERT INDUSTRY TO THE POTENTIAL COMMON CAUSE' FAILURE.
e-THE PUMP MANUFACTURER DESIGN DRAWING SPECIFIES CARBON STEEL BOLTSLBUT ONLY SPECIFIES STEEL LOCKWASHERS'FOR THE SHAFT COUPLINGS.
THE LICENSEE.USED CARBON STEEL-BOLTS WITH STAINLESS STEEL LOCKWASHERS FOR BOTH PUMPS WHEN THEY WERE REASSEMBLED.
o -THE LICENSEE PLANS TO DISASSEMBLE AND INSPECT THE PUMPS AGAIN AT THE NEXT REFUEL OUTAGE.
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GRAND GULF BRIEFING 94-11
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KEYED 7 COUPLING LY l,
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FIGURE 1 - STANDBY SERVICE WATER PUMP
-i
GRAND GULF
'- BRIEFING 94-19'-
-l PUMP SHAFT p
CAPSCREW LOCKWASHER w2 wgRETAINER l
V2 f".
Ph N
q-N m{4 N j
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8 SPLIT RING
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i SLEEVE KEY k
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FIGURE 2 - SSW PUMP COUPLING (TYPICAL OF 61 1
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94-11~
m SOUTH TEXAS, UNITS 1 & 2 DEFICIENT SURVEILLANCE OF CONTROL ROOM AIR DAMPERS FEBRUARY 1, 1994 u
PROBLEM d
THE BACKUP BATTERY THAT OPERATE THE DAMPERS IN THE CONTROL.
1 ROOM EMERGENCY FILTERING AND MAKE UP SYSTEM WAS NOT OPERABLE.
l CARSE BACKUP BATTERY SURVEILLANCE WAS NEVER PERFORMED.
SAFETY SIGNIFICANCE POTENTIAL DEGRADATION OF CONTROL ROOM VENTILATION SYSTEM DURING EMERGENCY OPERATION WITH A SINGLE TRAIN FAILURE.
BACKGRQHHQ e'
EACH SOUTH TEXAS NUCLEAR UNIT IS EQUIPPED WITH THREE 50% CAPACITY HVAC TRAINS, EACH WITH A MAKEUP AIR FILTER.
UNIT.
i e
THE FUNCTION OF THE MAKEUP AIR FILTER UNITS IS TO q
PROVIDE FILTERED MAKE UP AIR FOR MAINTAININGLPOSITIVE R
PRESSURE FOR CONTROL ROOM HABITABILITY DURING DESIGN BASIS EVENTS.
THE FANS ARE POWERED FROM THE RESPECTIVE SAFETY GRADE 120VAC POWER WITH A BACK UP FROM-SAFETY GRADE STATION BATTERY.
CONTACT:
T. K0 SHY, NRR/ DORS AIT: _HQ
REFERENCE:
10 CFR 50.72 #26721 SIGEVENT: _HQ a
e-e m
3
. SOUTH TEXAS, 94-11 UNITS 1 & 2 o
THE DAMPERS FOR THIS SYSTEM ARE POWERED NORMALLY BY CLASS 1E INVERTER WITH A LOCAL LITHIUM BATTERY FOR BACK UP.
DISCUSSIDH o
THE LICENSEE IDENTIFIED THAT ALL LeCAL BACK UP BATTERIES WERE DEPLETED.
o DAMPER CONTROLS AND THE LITHIUM BATTERIES WERE MADE-BY BORG WARNER.
o THIS DAMPER IS NORMALLY CLOSED AND IS MODULATED TO MAINTAIN 1000CFM MAKEUP WHEN THE SYSTEM IS IN SERVICE.
o
~ LOSS OF AC POWER AND THE FAILURE OF THE LOCAL BACK UP 4
BATTERY COULD LEAVE'THE DAMPER OPEN.
(THIS ASSUMES IE BATTERY DEPLETION AND EDG FAILURE IN THE SAME TRAIN).
o IF DAMPER IS IN OPEN CONDITION-SOME AMOUNT OF FILTERED AIR COULD FLOW BACK THROUGH THE AFFECTED TRAIN.-
o THE LICENSEE'S' FINAL EVALUATION DETERMINED THAT THE EXISTING FAILURES OF THE BACKUP BATTERIES IN ALL THREE-TRAINS WOULD NOT PREVENT THE SYSTEM:FROM PERFORMING ITS SAFETY FUNCTION DUE TO THE ABILITY OF THE. SYSTEM T0-PROVIDE ADEQUATE AIRFLOW TO THE CONTROL ROOM EVEN WITH BYPASS' FLOW THROUGH A FAILED-OPEN DAMPER.
o THE EQUIPMENT QUALIFICATION TEST REPORTS INDICATED THE BACK UP DAMPER BATTERY STATUS TO BE MONITORED BY THE PLANT COMPUTER; HOWEVER THIS FEATURE WAS NOT IMPLEMENTED AT'STP.
m.
. SOUTH TEXAS, 94-11 UNITS 1 & 2 o
NO SURVEILLANCE WAS PERFORMED ON THESE BATTERIES.
o.
THESE BATTERIES WERE NOT EQUIPPED WITH'AN AUTOMATIC CHARGING CAPABILITY.
o THE BATTERY QUALIFICATION PROGRAM INCORRECTLY INDICATED-10 YEAR SERVICE LIFE FOR THE BATTERY.
(REPLACEMENT WAS ASSUMED T0 BE BASED ON SURVEILLANCE SINCE IT WAS MONITORED BY PLANT COMPUTER) o THE LICENSEE REPLACED THE BATTERIES AND REVIEWED OTHER AREAS FOR SIMILAR OVERSIGHT.
o THE.SAME DESIGN AND THE PROBLEM WAS APPLICABLE TO FUEL HANDLING BUILDING EXHAUST SYSTEM.
LICENSEE ANALYSIS CONCLUDED THAT NO 0PERATOR ACTION IS NEEDED TO MAINTAIN OFFSITE AND CONTROL ROOM DOSES WITHIN LIMITS.
o BRAIDWOOD UNITS 1 & 2 REPORTED THE SAME PROBLEM AFTER SELLING THEIR SPARE BATTERIES TO SOUTH TEXAS UNITS.
FOLLOWUP o
FOLLOWUP DISCUSSIONS WITH THE MANUFACTURER DID NOT IDENTIFY ANY OTHER LICENSEES THAT ARE AFFECTED..
ENCLOSURE 3 REACTOR SCRAM Reporting Period: 03/07/94 to 03/13/94 VfD YtD
'A80VE BELOW YTD gg RL NT & UNIT RQgg
]Jf1
$$g CWPLICAfl0NS} }}} IgIM ' 03/12/94 NINE MILE POINT 2 100 SA Equipnent f ailure NO 1 0 1 ) l i i Notes Yeer To Date (YTD) Iotels Include Events Within the Calendar Year Irdicated By The Erd Date of the speelfled Reporting Period itS*10 Page:1 03/28/94
e COMPARISON OF WEEKLY SCRAM STATISTICS WITH INDUSTRY AVERAGES PERIOD ENDING 03/13/94 NUMBER 1994 1993 1992 1991* 1990* OF WEEKLY WEEKLY WEKLY WEEKLY WEEKLY SCRAM CAUSE SCRAMS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE (YTD) POWER GREATER THAN OR EQUAL TO 15% EQUlPMENT FAILURE
- 1 1.75 1.83 2.62 2.88 3.38 DESIGN /INSTALLAi!ON ERROR
- O 0.00 0.04 OPERATING ERROR
- 0 0.00 0.27 0.23 0.58 0.48 MAINTENANCE ERROR
- O 0.49 0.52 0.40 EXTERNAL
- 0 0.00 0.13 OTHER*
0 0.00 0.02 0.23 Subtotal 1 2.24 2.81 3.48 3.46 3.86 POWER LESS THAN 15% EQUlPMENT FAILURE
- O 0.19 0.38 0.40 0.29 0.40 DESIGN / INSTALLATION ERROR
- 0 0.10 OPERAflNG ERROR
- 0 0.10 0.13 0.13 0.15 0.08 MAINTENANCE ERROR
- O 0.00 0.02 0.06 EXTERNAL
- 0 0.00 0.04 OTHER*
O 0.00 0.06 $2 total 0 0.39 0.57 0.65 0.44 0.48 ) total 1 2.63 3.38 4.13 3.90 4.34 1994 1993 1992 1991 1990 NO. OF WEEKLY WEEKLY WEEKLY WEEKLY WEEKLY KRAM TYPE SCRAMS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE (yid) TOTAL AUTOMATIC SCRAMS 1 1.85 2.44 3.06 3.25 3.21 TOTAL MANUAL SCRAMS 0 0.78 0.94 1.02 0.65 1.19 TOTALS MAY DIFFER SECAUSE OF ROUNDING OFF
- Detailed breakdown not in database for 1991 and earlier
- EXTERNAL cause included in EQUIPMENT FAILURE
- MAINTENANCE ERROR and DESIGN / INSTALLATION ERROR causes included in OPERATING ERROR OTHER cause included in EQUIPMENT FAILURE 1991 and 1990 l l 1 1 ETS 14 Page 1 03/28/94 .J
9 7 FOTES 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 i OPERATING LICENSE. 2. PERSONNEL RELATED PROBLEMS INCLUDE HUMAN ERROR, PROCEDURAL DEFICIENCIES, AND MANUAL STEAM GENERATOR LEVEL CONTROL PROBLEMS. 3. COMPLICATIONS: RECOVERY COMPLICATED BY EQUI.PMENT 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 Manual and Automatic Scrams for 1992 ------------------ 212 Manual and Automatic Scrams for 1993 ------------------ 175 Manual and Automatic Scrams for 1994 --(YTD 03/13/94)-- 27 .}}