05000482/LER-1996-002, :on 960130,lost a Train ESW Due to Icing on Trash Racks.Contingency Plans Developed to Be Implemented Whenever Lake Temp Drops to 40F or Lower & Air Bubblers Being Maintained in Outer Bays to Sweep Frazil Ice
| ML20100Q414 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 02/29/1996 |
| From: | Lindsay W WOLF CREEK NUCLEAR OPERATING CORP. |
| To: | |
| Shared Package | |
| ML20100Q393 | List: |
| References | |
| LER-96-002, LER-96-2, NUDOCS 9603110626 | |
| Download: ML20100Q414 (12) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv), System Actuation 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(vi) 10 CFR 50.73(a)(2)(x) |
| 4821996002R00 - NRC Website | |
text
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WOLF CREEK GENERATING STATION 05000482 1 OF 12 TITLE (4)
Loss of A Train Essential Service Water Due to Icing on the Trash Racks EVENT DATE (5)
LER NUMBER (6)
REPORT DATE (7)
OTHER FACILITIES INVOLVED (8)
MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR F AckJTY NAME DOCKET NUMBER NUMBER NUMBER 01 30 96 96 002 00 02 29 96 C***""
'^ " "^""
OnRATING THIS REPORT IS SUBMITTED PURSUANT TO TKB REQUIREMENTS OF 10 CFR 5: (Check one or more) (11) 1 20.402(0) 20.405(c) 50.73(a)(2)(iv) 73 71(b)
POWER 20.40e(a)(1)(l) 50 36(c)(1) 50.73(a)(2)(v) 73 71(c) 98.3 %
20 405(a)(1)(u) 50 36(c)(2) 50 73(a)(2)(vu) i OTHER 20 405(a)(1)(iii) 50.73(a)(2)(!)
50 73(a)(2)(viii)(A) 50.73(a)(2)(vi)
- ;.jg 20.405(a)(1)(iv) 50.73(a)(2)(u) 50.73(a)(2)(vin)(B) 20.405(a)(1)(v) 50.73(a)(2)(un) 50.73(a)(2)(x) s LICENSEE CONTACT FOR THIS LER (12)
]
NAME TELEPHONE NUMBER (include Area Code)
William M.
Lindsay Manager Performance Assessment 336-364-8831 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
CAUSE
system COMPONENT MNACTURER REPORTABLE
CAUSE
avu REM COMPONENT MANUFACTURER REPORTABLE TO NPROS TO NPROS SUPPLEMENTAL REPORT EXPECTED (14)
EXPECTED MONTH DAY YEAR YES X
NO (tf yes completed EXPECTED SUBMISSION DATE)
ABSTRACT:
On January 30, 1996, at 0337 CST, operators in the Wolf Creek Generating Station (WCGS) Control Room manually tripped the reactor due to ice build-up on the circulating water (CW) traveling screens. The ice inhibited flow to the CW pumps and caused pressure and flow oscillations. As part of the initial actions taken when the ice was discovered, the A and B Essen*ial Service Water System (ESWS) pumps were started. Approximately six hours later, the A ESWS pump was secured due to decreasing bay level and high differential pressure across the strainer. The cause of decreasing bay level was later determined to be ice build-up on the ESWS trash racks.
The B ESWS train experienced similar icing conditions, but remained operable. Based on ESWS conditions and the inoperability of the turbine driven auxiliary fcedwater pump due to a packing leak, a Notification of t.ir,m al Event (NUE) was declared at 0846 CST.
The NUE was terminated later that day, but was relnstated on January 31, 1996, due to continued icing conditions in the ESWS bays (refer to WCNOC LER 96-001-00 regarding the loss of CW and the subsequent reactor trip).
9603110626 960229 U
PDR ADOCK 05000482 S
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Wolf Creek Generating Station 05000482 96 002 00 2
OF 12 TEXT (if more space is required, use additional copies of NRC Form 366A) (17)
PLANT CONDITIONS AT THE TIME OF EVENT MODE:
1 Power level:
98.3%
RCS Temperature:
584.6' Fahrenheit (F)
RCS Pressure:
2235 psig Mind Speed:
10-25 MPH Lake Level:
1086.4 Air Temperature:
Approximately 7'F Dtwpoint:
Approximately l'F Windchill:
- - 12*F to -3 3*F Circulating Water Condenser Inlet Temperature:
32.4*F l
l The A and C Circulating Water (CW) pumps (KE-P]
were running and the B CW pump was tagged
)
out for preventive maintenance.
The A and C Service Water (SW) pumps (KG-P) were supplying service water. Service Water pump B was tagged out for maintenance.
The low flow SW pump was available.
The Circulating Water Screenhouse (CWSH) traveling screens (KE-SCN] were in the manual mode on slow.
BASIS FOR RhPORTABILITY On January 30, 1996, at 0337 CST, Wolf Creek Generating Station (WCGS) Control Room operators manually tripped the reactor (AB-RCT) which resulted in actuation of the reactor protection system (JD] and multiple engineered safety features (JE]. The decision to trip the reactor was based on icing conditions on the circulating water (CW) traveling screens preventing flow to the CW pumps (refer to LER 96-001-00).
At 0747 CST, the A Essential Service Water System (ESWS) pump (BI-P) was secured due to decreasing bay level and high differential pressure across the strainer (BI-STR).
The dscreasing bay level and high differential pressure were later determined to be caused by ice build-up on the ESWS trash racks (BI-RCK).
At 0846 CST, a Notice of Unusual Event (NUE) was declared based on icing in the A ESWS bay and the inoperability'of the turbine driven auxiliary feedwater pump (TDAFWP) (BA-P].
The NUE was terminated at 1758 CST, on January 30, 1996.
Another NUE was declared on January 31, 1996, at 1000 CST, due to continued icing conditions in the ESWS bays.
The inoperability of the ESWS A train was due to the failure of the ESWS design to meet the environmental conditions of the original plant design basis. This event is being reported due to the discovery of a design deficiency pursuant to 10 CFR 50.73 (a) (2) (vi).
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Wolf Creek Generating. Station 05000482 96 002 00 3
OF 12 l
TEXT (if more space is required, use addmonal copes of NRC Form 366A) (17)
DESCRIPTION OF EVENT
Events on Janumev 30, 1996 At 0149 CST, CW alarms annunciated in the Control Room. The Site Watch was dispatched to investigate the cause. At 0158 CST, CW traveling screen emergency alarms annunciated in the Control Room. The alarms indicata increased differential pressure across the j
traveling screens (lake level versus bay level).
The Site Watch reported that the CW J
traveling screens to bays 1 and 3 were frozen and not rotating. At 0158 CST, due to oscillating-SW pressure, the B ESWS pump was started and the ESWS was isolated from.the SW System. At 0211 CST, the A ESWS pump was started. The operator closed the SW supply.
valves (KG-V] for ESWS (EF HV-23, 24, 25 and 26) ~ and opened the return lines from ESWS to
)
SW (EF HV-39, 40, 41 and 42),
The ESWS header valves returning to the Ultimate Heat Sink (UHS) (BS] (EF HV-35 ond 38) were also closed to maximize flow back through the SW header (refer to Figure One).
(To ensure some warming line flow is maintained, EF HV-37 is 90%
open and EF HV-38 is 65% open when in the closed position.)
The system was aligned in this manner with the intent of increasing flow to the SW header while continuing to supply the existing SW loads.
It was not recognized at the time that this alignment would reduce warming line flow.
At 0337 CST, the Control Room received word from the Site Watch that the CW hay levels were 12-13 feet below normal and that the low flow SW pump was vibrating. Control Room operators manually tripped the reactor, secured the CW pumps, fast-closed the Main Steam Isolation Valves (SB-ISV), broke condenser vacuum (KE-COND) and controlled the reactor coolant system (RCS) (AB) temperature with the steam generator atmospheric relief valves (SB-RV).
At 0503 CST, while stabilizing the plant in MODE 3, the Control room was notified the TDAFWP was spraying water. At 0505 CST, the Turbine Building Watch reported to the Control Room that the TDAFWP shaft gland packing was leaking and notified Maintenance. At 0514 CST, the TDAFWP inboard seal packing was determined to have failed and the pump was declared inoperable.
Steam generator water levels were being maintained by the two Motor Driven Auxiliary Feedwater Pumps. (MDAFWP) (BA-P).
The packing was replaced and the TDATWP declared functional at 1411 CST, on January 30, 1996.
The required surveillances for operability will be completed during 9 tart-up from Refuel VIII.
At 0747 CST, the Control Room received a report that A ESWS bay level was low.
The A ESWS pump was secured due to low discharge prassure and high differential pressure across the btrainer. The Control Room declared an NUE at 0846 CST, based on the Administrative Tree l
of the Emergency Action Levels (EALs) due to the potential degradation of the ESWS system and che inoperability of the TDAFWP.
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RavIsson NUMBER MUMBER Wolf' Creek Generating Station 05000482 96 002 00 4
OF 12 TEXT (if more space is required, use additional copes of NRC Form 366A) (17)
I At 0800 CST, the relief crew Supervising Operator, while in the Control Room supporting the on-shift. crew, identified the abnormal ESWS/SW valve line-up and brought it to the attention of the on-shift Supervising Operator. Operators then correct ly aligned the ESWS return flow to the UHS per procedur'. SYS EA-120, "SW System Startup."
At-1230 CST, maintenance personnel reported to the Control Room that tents and temporary haaters (HTR) were installed on both A and B ESWS bays. The heaters blew warm air onto ths surface of the bays in an attempt to dissipate the ice.
At 1531 CST, MODE 4 was entered. At 1543 CST, the A ESWS pump was placed in service. At 1745 CST, the A ESWS train was declared operable based on the following:
1.
ESWS system was filled, vent.ed, and running properly;
- 2. Supplemental heating was available and functioning (one kerosene fired space heater [HTR) per train was ducted and tented to the ESWS outer bay in front of the trash racks, and two electric heaters per train in the ESWS pumphouse, were ducted to the bays); and,
- 3. A decision was made to station a continuous watch to observe the bay levels, watch for icing, and monitor the kerosene fired space heaters.
At 1758 CST, the NUE was terminated based on the operability of the A ESWS train. At this time, the accumulation of fra:ril ice on the ESWS trash racks had not been discovered.
At '
j 1923 CST, Control Room operators secured the A ESWS due to fluctuating pump discharge pressure and flow. At 1934 CST, the Site Watch reported a decrease in the A bay level.
i Control Room operators reviewed the EALS, and determined that none were applicable since B ESWS was operable, the plant was in MODE 4, and no auxiliary feedwater was required.
At i
2002 CST, the Control Room received a report from personnel at the ESWS pumphouse that the B bay level was slowly decreasing. At 2012 CST, the Control Room commenced a RCS cooldown j
using t}.e B train Residual Heat Removal System [BP).
This caused an increase in the warming line water temperature to the B ESWS.
The level in the B bay subsequently recovered.
At 2044 CST, the Site Watch reported to the Control Room that the A ESWS bay level was normal.
He then rolled the A ESWS traveling screen, and it moved treely in f,he slow opeed.
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1 Wolf Creek Generating Station 05000482 96 002 00 5
OF 12 TEXT (If more space is required, use additional copes of NRC Form 366A) (17)
At'2100 CST, the Control Room reviewed the EALs and decided that a Site Area Emergency (SAE) would be appropriate if the B ESWS bay level decreased below 1070' (the Technical Specification limit for th3 UHS) or if the B ESWS pump would not run.
At 2128 CST, the Site Watch reported that both A and B ESWS bay levels were equal with the lake level (1086.4').
The A ESWS pump was again started at 2214 CST, and secured at 2227 CdT, due to dscreasing flow and pressure.
Events of Jannmev 31, 1996 At approximately 0730 CST, the Vice President Operations and the Manager Operations decided that if the.B ESriS bay level reduced to 1083' an Alert would be the appropriate EAL.
At 0843 CST, divers went into the A ESWS bay.
At 0855 CST, the divers were out of the bay and reported that the trash racks had a build-up of ice that was preventing flow and inhibiting suction to the A ESWS pump. At 1000 CST, an NUE was declared using the Administrative Tree of the EALs due to a potential degradation of the ESWS.
At 1435 CST, emergency temporary modification (TMO) 96-007-EF was authorized to provide air sparging (introduction of air or gas into a liquid) to the A ESWS warming line. The air was supplied from a temporary air compressor [ CMP) into the warming line veit line.
Additionally, two air hoses were lowered into the outer bay, their open end weighted with heavy objects to prevent movement, to introduce air directly into the A ESWS outer bay.
A flanged connection to the ESWS chemical injection header was.also used to inject heated water from a portable tank heater into the warming line.
At 1548 CST, divers entered the A ESWS bay and found the ice blockage had moved two feet l
back from the trash rack. At 2045 CST, it was reported to the Control Room that the ice l
had cleared the bay area. At 2100 CST, per temporary procedure 96-006, the Control Room aligned SW return flow to the UHS which increased the heat load to the ESWS warming lines.
At 2248 CST, the plant entered MODE 5.
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OF 12 i
TEXT (11 more space is required, use additional copies of NRC Form 366A) (17)
Events of February 1.
1231 At 0243 CST, the A ESWS pump was started per SYS EF-200, " Operation of the ESWS System."
At 2149 CST, the Control Room authorized temporary mcdification (TMO) 96-008-ZE which lowered the air bubbler on the A ESWS outer bay from its previous position, of approximately 15 feet below the water level, to the bottom of the outer bay.
The A ESWS pump parameters were monitored during this evolution to verify that pump performance would be acceptable with the air bubbler at any elevation in the outer bay.
At 2330 CST, the Control Room received a report that temporary procedure 96-010 was complete and all the operating parameters on the A ESWS pump were acceptable.
The Vice President Plant Operations chartered an Incident Investigation Team (IIT) to perform a thorough root cause evaluation of the event. The team'was composed of 26 i
individuals including personnel from Wolf Creek Generating Station, other nuclear I
utilities, vendors, the Institute of Nuclear Power Operations, and the U. S. Army Corps of Engineers.
EY9nts of February 2.
1996 At 1005 CST, the A ESWS was declared operable and the NUE terminated, based on consistent bay level and steady pressure and flow readings.
ROOT CAUSE The root cause of this event was deficiencies in the warming line design verification on l
the original ESWS warming line. The errors resulted in an insufficient warming line flow rate based on the actual warming line temperature.
Icing conditions were hastened by ESWS valves being misaligned for approximately 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> when the system was started on January 30, 1996 Detailed explanation:
The accumulation of frazil ice starts when water becomes supercooled or drops below its freezing temperature. The water will supercool first at the surface, and when turbulence is present, will mix through the entire lake depth.
Smal;l crystals of ice - frazil ice -
will be carried along with the supercooled water.
Because the crystals are supercooled, and rapidly grow in size, they stick to any object they come into contact with, including trash racks.
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OF 12 TEXT (If more space is required, use addmorial copies of NRC Form 366A) (17)
A design calculation performed in 1976 specified a warming line flow rate of 4000 gpm for che prevention of frazil ice.
This was determined using valid, conservative methods, but assumed that the temperature of the warming line flow would be at least 3'F above freezing. When the ESWS icing conditions developed, the estimated actual warming line temperature was approximately 1*F above freczing. Using current U.S. Army Corps of Engineers' recommendations, the flow required to prevent frazil ice for a warming line flow temperature of l'F abcVe freezing would be approximately 4,050 gpm.
The UHS and warming line piping diameters and elevations are such that portions of these lines operate with partial pipe flows and with the dry portions not vented. This condition was apparently not foreseen by the piping designer. The calculation methodology used for sizing the warming line was therefore invalid.
The warming line flow rate during an accident line-up for the piping as-built configuration cannot be readily calculated or measured with a high degree of certainty.
It is estimated to have been about 2500 gpm.
Warming line flow was further reduced to an estimated 1700 gpm for approximately 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> on January 30, 1996, due to an improper valve lineup.
Contributing Factor to the Root Cause The incorrect alignment of the ESWS system at approximately 0200 CST, on January 30, 1996, restricted warming line flow to the ESWS intake bay trash racks and hastened the accumulation of frazil ice.
This lineup was corrected at 0800 when ESWS return flow was aligned to the UHS per procedure SYS EA-120.
The ESWS valve misalignment occurred when the operator performed the ESWS/SW valve lineup, without the use of a procedure, as directed by the Shift Supervisor.
The alarm response procedure failed to provide the steps required to place ESWS in service, and the specific ESWS/SWS lineup procedure was not used.
This is only acceptable as an immediate response I
and requires a timely verification when such actions are taken without approved procedures. The root cause was a failure on the part of the Control Room crew to provide timely verification of the ESWS line-up.
Imprecise communications about this lineup contributed to this event.
Failure to have the procedure in 'tand increased the potential that the line-up could be done incorrectly, and made effective crew communication and timely verification more important. Three examples of ineffsetive crew communications contributed to the incorrect line-up:
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OF 12 TEXT (if more space is required, use additional copies of NRC Form 366A) (17)
When the shift Supervisor instructed the Reactor Operator to start the ESWS pumps, e
he did not fully communicate his expectations to isolate the ESWS from the SW.
When the Reactor Operators were walking the control boards during shift turnover, the oncoming Reactor Operator did not gain a full understanding from the on-shift Reactor Operator of the abnormal ESWS line-up.
When the on-coming Reactor Operator recognized the abnormal line-up, he failed to communicate his observation to his Supervising Operator.
Corrective Actions Cn=nleted for the Desian Error The below contingency plans were developed as short term corrective actions to be implemented whenever the lake. temperature is 40*F or lower until long term actions are implemented. Refinements to the contingency plans will be made as appropriate based upon technical reviews.
1.
Air bubblers are being maintained in each outer bay to sweep frazil ice from the ESWS trash racks. Once the lake reaches the critical environmental conditions to produce frazil ice, and the ESWS pumps' suction begin to pull supercooled water with frazil ice into the inlet, air bubblers provide a brooming, or sweeping effect upward across the trash rack to prevent or break-off frazil l a accumulation.
Air bubbling also creates a high circulation ratio which promotes mixing and heat transfer. As a minimum, two air compressors are located at the ESWS pumphouse. A minimum of one air compressor is aligned for bubbling the outer bay with an additional compressor as a backup.
2.
Tents will be maintained over the grating of the outer bay to provide additional freeze protection.
3.
A dedicated cognizant individual will be stationed at the ESWS pumphouse 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> a day.
This individual will:
- 1) monitor the air compressors, 2) monitor the tents, and 3) watch for formation of ice in the outer bays.
The Control Room will be notified immediately upon compressor failure, tent degradation or ice formation in the outer bay.
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Corrective Actiana to be ca-lated for th= Danicm Error l
1 The. hydraulics of the ESWS discharge to the UHS and the warming line to the ESWS pumphouse will be changed to establish and distribute the proper amount of flow to the ESWS pumphouse warming line.
Due to the low amount of heat (approximately l'F temperature rise) available, a higher flowrate than the original-design (4,000 gpm) may be required.
The upper limit for this warming line flow will be dictated by the UHS cooling characteristics and the temperature range chosen'for this mode of operation. To achieve the proper flow, back pressure on the ESWS discharge to the UHS must be raised downstream of the ESWS warming line tee.
The back pressure orifices located upstream-in the powerblock ESWS discharge lines will be re-evaluated to prevent increasing the overall backpressure on the ESWS to an unacceptable level. These corrective actions will be completed by October 1, 1996.
Corrective Actions for tha Mimaliera==at of ESNB 1.
By the end of Refuel VIII, methods for tracking urgent control room actions and subsequent verification of acceptability of these actions will be evaluated.
2.
Enhanced communication training will be provided to the Control Room crews. The training will stress using clear concise instructions, and not taking the watch until the relieving individual has a full understanding of ~~ abnormal conditions.
Through Instructor and Shif t Supervisor interventions, comn acations will be critiqued to verify not only compliance with standards, but to also ensure a complete understanding of all the issues by all crew members. The need to bring abnormal conditions to the attention of supervision will be reinforced.
Enhanced communication training will be provided to the Control Room crews by May 31, 1996.
3.
The alarm procedures for the top-level alarms will be revised. These revisions will incorporate all expected short term operator actions into the applicable alarm procedure. The alarm procedures for the ESWS, SW system, and CW system will be revised prior to entry into MODE 4 from Refuel VIII.
A priority based schedule for the remaining alarm procedures will also be developed by MODE 4.
All alarm precedure revisions will be completed by October 1, 1996.
~
NRC FORM 366 U.S.,
NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 j
(5-92)
EXPIRES 5/31/95 j
ESTIMATED BURDEN PER RESPONSE TO COMPLY
=
+
WITH THIS INFORMATION COLLECTION REOUEST:
. LICENSEE EVENT REPORT (LER) 50.0 HRS.
FORWARD COMMENTS REGARDING l
j TEXT CONTINUATION STME TO THE NNM M RECORDS MANAGEMENT BRANCH (MNBB 7714), U.S.
1 1-NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 206550001, AND TO THE PAPERWORK REDUCTION j
PROKCT (31500104), OFFICE OF MANAGEMEM AND i
BUDGET, WASHINGTON. DC 20503.
FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3).
YEAR SEQUEbrTIAL REVIs tost NUMBER MMBER l
- - Wolf Creek Generating Station 05000482 96 002 00 10 OF 12 TEXT (if more space is required, use add bonal copes of NRC Form 366A) (17)
I
SAFETY SIGNIFICANCE
The ESWS is a safety-related system thal frovides cooling for components required for safe i
shutdown of the reactor. The ESWS consists of two redundant cooling water trains,'and the system is normally not in operation. During normal plant operations, the ESWS within the i~
power block receives water from the nonsafety-related SW system. The SW supplies ESWS
~
loads and other station heat loads. After removing heat from plant components, the heated water is returned to the SW System and/or the UHS depending on plant conditions.
~
Following an engineered safety features (ESP) signal, the ESWS is isolated from the SW by automatically closing the associated ESWS/SW interface motor-operated valves (MOV).
Both ESWS pumps are automatically started after the receipt of an ESF signal..
After removing heat from plant components, the water is returned to the UHS.
Freeze protection for the ESWS is provided by varming lines from each ESWS discharge line to the UHS during normal,
?
off normal, and accident conditions. The ESWS is designed so that during system operation, freezing of the trash racks is prevented due to warming lines per Updated 4
Safety Analysis Report (USAR) Section 9.2.1.2.
The ice blockage would have prevented the A ESWS from performing its intended design function. However, the B ESWS and SW were available throughout the event.
The significance of this event was elevated based on the inoperability of the TDAFWP. The TDAFWP was declared inoperable, at 0514 CST, on January 30, 1996, due to a packing leak on the inboard seal. At 1411 CST, the packing was replaced and the TDAFWP declared functional.
PREVIOUS SIMILAR OCCURRENCES There have been no previous occurrences where frazil ice accumulation on or inadequate warming line flow to ESWS trash racks has caused the system to become inoperable.
etc FOPN, ass u.s. uncLsaa asogLAronx cceoussIon APraovso sY cMa No. 3150-0104 (5 92)
EXPIRES 5/31/95 ESTNATED BURDEN PER RESPONIE TO COWLY WTH THIS INFORMATION COUJiCTION REQUE8n LICENSEE EVENT REPORT (LER) 50A HRS.
FORWARD COMMENTS REGARDING N CON M M BURDEN ESTNATE TO THE INPORMATION AND RECORDS MANAGEMENT BRANCH (nsS8 7714), U.S.
NUCU!AR REGULATORY COMMISSION, WASHINGTON, DC 206064001, Alm TO THE PAPERWORK REDUCTION PROJECT (31504104), OFFICE Op umansumT AND bud 0er, WASHINGTON, DC 20003.
FACILITY NAME (1) h a NUMBER (2)
LER NUMBER (s)
PAGE (3)
Ysaa ss0UmrrlaL asysstem weesa massa Wolf Creek Generating Station 05000482 96 002 00 II OF 12 TEXT (if more space a requwen, use adebonal copass of NRC Form 366A) (17)
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WRC FORM ass u.s. 44UcI. san asoutAronY cosetIssIou APPacvru aY cMa No. 31s0 0104
~~
(5-92)
EXPIRBS S/31/95 ESTRAATED SIAtDEN PfiR RESPONSE TO cot #LY WITH T)tB IPPORMATION COUJiCTION REQUEST:
LICENSEE EVENT REPORT (LER) 60.0 HRS.
FOfMARD COMMENTS REGARDING N CM6W BURDEN ESTR4 ATE TO THE INFOfE4ATION AND RECORDS MANAGEMINT BRANCH p 7714), U.S.
NUCLEAR REGULATORY COMMISSION, VMSHINGTON, DC 200660001. AND TO TIE PAPIBMOfWC ftEDUCTION PROJECT (31804104), OFFICE OF uaN AND BUDGET, WASHINGTON DC20003.
FACILITY.""2 (1) h4-NUMBER (2)
LER siUneSR (6)
, PAGE (3) i Yana sageurnas, navissam musosa susmaa Wolf Creek Generating Station 05000482 96 002 00 12 or 12 4.
TEXT Of more spam is requwen, use modeones copies of NRC Form 366A) (17)
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