ML19322D181
| ML19322D181 | |
| Person / Time | |
|---|---|
| Site: | Oconee, Crane  |
| Issue date: | 08/24/1979 |
| From: | Robert Lewis NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Bryan S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML19322D180 | List: |
| References | |
| TASK-TF, TASK-TMR NUDOCS 8002100025 | |
| Download: ML19322D181 (19) | |
Text
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NUCLEAR REGULATORY COMMISSlQN
?... !q,.,,fr _ ;.idi. i REGION 11 c,. Ypyg;y 1.8 101 MARIETTA sT., N.W., sulTE 3100
%4 * %/ * [
ATLANTA, G EORGIA 30303
%,4 AUG 2 41973 MEMORANDU'1 FOR:
Samuel E. Bryan, A/D for Field Coordination, DROI, IE FROM:
R. C. Lewis, Acting Chief, Reactor Operations and Nuclear Support Branch, RII SG.ECT :
IhTORMATION,_FOR NRC/TMI SPECIAL INQUIRY GROUP (H10-000113-H07)
Enclosed please find the information on Oconee as requested in paragraph 3 of the enclosure to the meno dated August 1, 1979, from S. E. Bryan.
It is our unicrstanding that paragraphs I and 2 will be pro -ided by other Offices.
t u.
R. C. Lewis, Acting Chief Reactor Operations and Nuclear Support Branch E:iclosure :
Oc::ee 1, 2, 3
+
CONTACT:
R. Mart.in 212-5534 I
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ENCLOSURE OCONEE 1. 2. 3 s
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The following list of significant operational events, incidents, occurrences and transients is provided in response to the July 24, 1979 request. The list was devehped by reviewing inspection reports, enforcement history, LER files and the
~
^ icer.see's log of incidents.
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??.eacter Trips The licensee's re. cords on' reactor. trips were examined and operational problems are summarized below.
Cause Unit 1 Unit 2 Unit 3 low Reactor Coolant Flow 4
4 0
1:tegrated-Control System 15 6
S inability to handle trans-ient resulting in high RC
- cutle teep, RC Pressure er Reactor Power.
- -:igh RC = Pressure due to 18 9
3 1:ss cf feedwater 3:anua". Trios
- 38 28 22 Total 75 -
47 33
ntentio:al. Manual Trips when performing tes.s'and other manual trips as recuired
~:7 pr:cedures
' Teedvarer System
- si T:e cperational problems experienced with the cain feedwater system have ieen a loss of one or both main feedwater pumps. Each pump has approximately a 60 percent capacity and with reactor power a,t or greater than 60 percent, a higi pressure reactor trip or manual trip results upon less of one main.
feed pu=p.
The pump loss problem has generally been traced to a ICS mal-function.
- C.her problems with the main feedwater system'have included mechanical f il a ures a.d less cf main feed pump condenser vacuum.
Feedvater system problems investigated by the licensee tc date are listed telew:
MAIN FEEDi?.;TEI SYSTEM
. :3 e Incident Unit-No.
Reportabl5 C OII;'79 Reactor Manually Tripped i
No When "B" Feedwater Pump Tripped 9
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a
,p, g.
n En:lo,sure (Oconea 1, 2, 3).
MAIN FEEDWATER SYSTEM Datt Incident Unit No.
Reportable 10/30/78 Reactor Trip Following 2
No Loss of FDW Valve Dif-ferential Pressure Control 10/03/78 Reactor Trip on High 2-No Pressure Due to FDW Pump B Trip 10/17/78 Reactor Trip on High 2
No Pressure FDW Pump B Tripped 1h18/75 Reactor Trip Due to FDW 1
No Swing when put in Auto 05/21/77 Reactor Trip. Following 3
No Problem With Feedwater Block Valves 10/ ~_2/ 76 Feedwater Pum,6 B Trip 2
No During Turbine Trip Test 01/02/76 Manual Trip Due to Loss 3
No of Both FW Pumps OE/_9/75 Manual Trip Due to Loss 2
No of FWP on low Vacuum 05/23/75 Trip Due to Loss of 2
No Feedwater 05/05/75_
Trip Due to FDW Pump A 2
No Trip During Thrust Bearing Wear Trip Test C2/27/75 Manual Reactor Trip 2
Nc
~ Following FW Pump Turbine Trip on Vacuum
- ,':E/74
. Runbach-to 15% Due to 2
No Decrease in FDW Flov
~
12 / C 9/ 7.'-
Reactor Trip on Reactor 3
N:
Prctection System High i
Flux Feedwater Lemand l
i I
1
- L_
h.
En-;fscre'(Ocone21,i2,3) -
~
MAIN FEEDWATER SYSTEM Date In~cident Unit No.
Reportable 10/17/74 Unit 3Trippehfrom16%
3 No Full Power.Due to Loss 3
of Feedwater 10/13/74
. Trip Due~to Loss of FDW 3
No Reactor Protection System Ch. A, B, and C Tripped 04/26/74 Manual Trip From 5% Full Power on Loss of FDW Pump
. Turbine 3.~
Emergency Feedwater System The problems with the emergency feedwater system have been associated with periodic surveillance testing of the turbine driven pump. The turbine trip mechanism would become out-of-adjustment, due to vibrations, and when a test start was initiated, the turbine would trip and the stop valve would ~
close.
This has been corrected through the preventive maintenance program.
On one occasion insufficient lube oil system pressure caused the turbine to fail to start on test.
Adjustments to the oil pressure switch were made and system operability restored.
!c date, the number of recorded incidents related tc. emergency feedwater systems are one for Unit 1, two for Unit 2, and five for Unit 3.
EMERGENCY FEEDWATER SYSTEi!
Late Incident Unit No.
Reportable G7/25/79 Emergency Feedwater Pump 2
No Was Declared Inoperable (Seal Leak) 06/21/79 Emergency FDW Pump Tur-2 Ne bine Rendered Inoperable
- 2/16/7,9 Emergency FDW Pump Would 3
No.
Not Start 11/C1/7SL Emergency FDW Pump Failed 1
No to Start During PT/1/A/600/11-h
.g 3b s'.
an n.
3ne p:ure (Oconte.I', 2, 3).
EMERGENCY FEEDWATER SYSTE.'1
-Date Incident-Unit No.
Reportable 04/27/78 Emergency FDW' Pump Turbine 3
No Failed to Start 11/13/76 Emergency FDW Pump Line 3
No From Hotwell Bent by Secondary Side Water Hanmer -
04/30/75-Emergency FDW Pump 3
UE-287/75-5 Discovered to Be Inoperable 01/21/75 Energency FDW Pump 3
No Recirc. Line Leak While Feeding Unit 2 OTSG's Sa f et-z Related Instrumentation 0peratienal problems incolving safety related instrumentation are divided ir.to two cain categories. These are failure of the. centrci rod drive (CRD) ireakers to instantaneously trip and required safeguards pressure tr:nsmitters te drift out of calibration.
The CRD events are summarized below and were partially respcasible for issuance of IEB 79-09; the ptcblem has been corrected at Oconee. Regulatory f:llcrup on these events is documented in IE Inspection Repcrts 50-269/79-5.
5 -270/79-5, 50-287 '79-5, 50-269/79-7, 50-270/79-7, 50-257/79-7 and the rcutine. followup on each reportable event.
CONTROL R0D DRI\\T.
Late Incident Unit No.
Reportable
~
C_/OS/79 CRD Breaker CB-1 Failed 1
RO-269/79-5 to Open During On-line Test 01/22/?9 CRD Breaker CE-1 Failed 1
RO-269/79-5 to Open During On-Line Test 0*./IE/79 CRD Breaker e10 Did Not 3
R3-25 7 '7 c-2 Trip During On-Line Test, IP/0/B/305/3A f.
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- nclesure (0 cones 1,12, 3) - ~
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CONTROL ROD DRIVE E4:e' Incident Unit No.
Repcrtable 12/17/78 CRD Breaker #11 Failed 3
No to Open During Startup 05'/07/75 CRD Breaker Failed in 3
A0-287/75-11 Untripped Condition 01/20/74 Failure of CRD Breaker 2
No CB-4 to Close on Unit Startup O?/23/73 Evaluation of CRD Breaker 1
No Unit to Trip When 1 X 3 Transformer Failed on April 23, 1973 The problem of engineered safeguards pressure transmitters drifting out of calibration has not been com Adjustments were made to the surveillance program related~pletely corrected.
to this instrumentation as a temporary fix. The -
t licensee is continuing its investigation and inspector followup continues.
'ihen the instrument calibration drif ts beyond the technical specification setpoint limit, the licensee repcrts the event as an LER.
The te=norary corrective action taken has been to adjust the setpoint conservatively and to perform surveillance of ten enough so that the drift is caught before the
!S setpoint is exceeded.
Subsequently, there have been no reportable events.,
The long terc corrective action being pursued by the licensee is to test a spare transmitter in an envircament similar to that where the instrumentaticr is in use. This work is underway.
Casual facters and final results of the test program are expected within several months.
This item is carried as an inspection followup item and will be closed in a future inspection report.
~he events related to this problem are liste'd below.
ENGINEERED SAFEGUARDS FRESSURE TRANSMITTERS
- ate Incident Unit No.
Repcrtable 10/23/75 ES Channel 3 RB Narrow 2
RO-: 2/75211 Range Pressure Trans-mitter Out of Calibration 05/11/7S Reactor Building Piessure RC-;i! 75-21 Trans=itters Out cf Calibratica r
I is
. _.. ~,
fr.cl:sure (Oconse 1, 2,l 3)
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' ENGINEEPID SAFEGUARDS PPISSURE TRANSMITTERS' Late Incident Unit No.
Reportable F
08/08/78-Reactor Building Pressure 1
RO-269/7c-17 Transmitter Less than Technical Specification Value 04/04/78 Analog Channel 12 Reactor 2
R0-270/78-5 Building Narrow Range Pressure' Transmitter Found Out of Technical Specification Value
' 12/05/77 Found ES Reactor Building 2
RO-270/77-16 Pressure Transmitter Valued Out of Service 11/28/77 Inoperable Pressure and 3
R0-287/77-16 Flow in Reac_ tor Protection System Channel A 06/19/75 ES Pressure Transmitter 3
A0-257/75-S Found Out of Calibration OTHER SArETY PILATED INSTRDENTATION Este Incident Unit No.
Repor:able 07/24/79 Feed Breaker to CTI 1
Not Issued (Transformer) k'ould Not Close - Isolated Main Feed Bus
. 05/22/79 PS-68 (Pressure Switch)
'2 RO-270/79-3 Discovered with a Setting in Excess of 4 psig
- 2/11/78 Reactor Trip on Pressure /
1 R0-269'75-27 Tecp. (Short in Coil of Tavg. Recorder)
- 1/25/75.
Engineered Safeguards 3
R0-257/75-IS
~ Analog Channel B. Tripped on Reactor Building High
~
Pressure
- -./23/75-ES Channel A Tripped
,, _ :..c-;-
-(Degraded Mode)-
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n
.-..~7
-n: h sure (0 conte 1, 2, 3) ~
OTER SAFETY REI.ATED INSTRIDENTATION Date Inc"ident Unit No.
Reportable 01/03/77 Reactor Trip on High 1
No Reactor Coolant Pressure
.=
Due to Failed ICS Module-05/28/75 Reactor Building High 1
A0-269/75-6 Pressure, Trip.
Pressure
-Svitch Set Over Limit 5.
Safety Related Ventilation The penetration' room ventilation system has been declared inoperable on a
~
number of occasions. A 1 ak in the main feedvater line that passes through the penetration room vill increase the humidity to saturation condition vithin the room and if the ventilation system was placed into operation, the high humidity would affect the cha. coal filters rendering them ineffective.
The licensee uses a humidity limit of <70% to declare the ventilation system
- perable. Above 70% relative humidity, the system is inoperable and Technical-Specification gives required action. To correct this problem, the licensee is chasidering alternate means for providing proper ventilation. In addition, a seal veld around the feedvater check valve hinge pin has bhen tried to eliminate the source of humidity. Final resolution for this problem has not been det' ermined. The events are listed below:
SAFETY RELATED VENTILATION Date Incident 17 nit No.
Reportable en 07/IS/79
. Penetration Room 1
-Not Issued Ventilation System Declared Inoperative 12/07/78 Penetration Room 3
. R0-2S7/78-19 Ventilation Trains A&B Inoperative
,i/29/77-Both Train's of Penetration 1
R0-269/77-21 Room Ventilation System Inoperable J
10/20/73 Penetration Roo= Integrity 1
No Breached I.
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.n:2:s.:re (0 con:e 1, 2, 3) '
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LP System The operational problems on the low pressure injection system have beea pri-arily valve failures and borated water storage tank level instrumentation proble=s.
The most recent problem has been the discovery of a tube leak on IA LPI cooler.
On two occasions, 2-LP-21 failed to open during a surveillance test. The problem was determined to be electrical and nas been repaired. Also, LP 12 and 14 on Units 1 and 2 experienced a broken guide stem.
These four valves have been replaced and no problems have been encountered since replacement.
(The LP 12 and 14 on Unit 3 are of a different design and did not recuire replacement.)
LOW PRESSURE INJECTION SYSTEM - VALES Date Incident Unit No.
Reportable Ct/05/77 2LP-21 Failed to Open 2
RO-270/77-6 During Reactor Building Spray Logic. Test
' ' / 21. 75 2LP-21 Failed to Open 2
E-2 70/ 75 - 19 During Checkout
- -/25f75 Guide Pin Discovered 2
A0-270/75-10 J
. Missing Frem 2LP-12
- 7/02/74 Piece Missing From 2LP-12, 2
E-2 70 / 72.- 3 Piece Missing From 2LP-14 The level instrumentation on the bcrated water storage tank failed on a
- r. umber of occasions due to purging of the sensing lens.
Additional heat tracing and insulation has been added to the sensing lines to correct this problem.
In addition, operators check the sensing line daily during freezing veather to verify that the insulation is present and that the heat trac;ng is energized.
The events are listed below.
Regulator'y fcl1.cw up is documented in Inspection Report 50-269/77-3, 50-270/77-3, and 50-2S7/. -3, during routine reviev and followup of the LER's listed below.
i 3
BORATED WATER STORAGE TA.'E i
Date Incident Unit No.
' Reportable
- /.9; 7S Borated Water Storage 1
RO-269,75-23
)
Tank Level 1 Trans-mitter Found Out of Calibratidn i
- 5/06/77 Channel 1 of FA
- ST Level
- ?-2; In.trumer.ta tion Jr.g e ra: ' e f
P 0 0 2 G R Fm aj
End_':::ure (0: ente 1, 2, 3)
BORATED WATER STORAGE TA.E Late Incident Unit No.
Reportable 01/16/77 BWST Level Instrument 1
R0-269/77-13 Channel Inoperable 01/12/77 BWST Level Instr.
1 R0-269/77-13 Channel Inoperable O!./09/77 BWST Level Instrument 1
RO-269/77-13 Inoperable Due to Plugged Impulse Line 01/11/77 Lost One Channel of BWST 2
R0-270/77-1 Level Instr. Due to Frozen Impulse Line 11/21/76 One Channel of BWST Level 3
RO-257/76-21 Instr.:
Frozen Impulse -
Line 12/19;75 Soth EWST Level Channels 1
A0-269/75-15 Inoperable Due to Frozen Impulse Lines
- il'. 75 Bust Level Instruments Out 3
A0-2E7'75-10 of Calibration - Level in Tank Low 12;'22/73 Loss of Eoth BEST Level 1
A0-269:'75-6 Channels
." I Syste:
An error in the ECCS small break analysis was reported by B&W and DPC in' April 1978.
The licensee has submitted a design change tc.NRR. The change was approved and has been installed at Unit 3.
Follovap is documented in IE Inspecticn Report 50-287/79-15 and 50-287/79-15.
The LER. RO-269/75-11,
.<as riven the routine follovup.
R: Sys.e:
The problems with RCS involved the reactor coolant and the specimen sample hcider.
Problems with RC pumps have beea:
- 1) me. tor oil fires. 2) seal water leakage; and 3) high RC flot.
niifications have been ccepleted to the pump acter c _'. s; ster
. i
.L e f i r:-
pr:ble: nas been resolved..'lodifica tions fe r the Eingham.;:: 7 =.- sea'.s have
- een ins.alled and this prcbler ap, rears tc be res:_.e:.
m%
h p)o/ M, $,. O fg U L g ',,
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Incl:sure (Ocon e 1, 2, 3) '
The high reactor coolant flow problem was identified on Oconee I during initial power escalation testing.
It was also identified en Oconee Units 2 and 3.
Investigation and followup on this item resulted in a change to the fuel assembly hol'ddown spring constant.
Discussions with NRR and the licensee resolved the "tta..
Inspection Reports discussing the high RC flow issue are as follows:
0-1 0-2 0-3 50-269/73-4 50-270/75-7 50-287/74-53 50-269/76-12 50-270/76-12 50-2S7/75-2 50-287/75-7 50-270/76-12 REACTOR COOLANT SYSTEM Date Incident Unit No.
Reportable 06/19/77 Motor 3B1 Reactor 3
No Coolant Pump, Over-heated 11;05/76 Explosion / Fire on 1A2 RC 1
No Pump While Adding Oil 04/D2/75 Indicated RC 51ow 113.67%
2 UE -27 0:' 75 - 7 of Design 01/31/75 Small Oil Fire on 2BI 2
No RC Pump 05/19/74 Leak From 2B1 RC Pump 2
No During Heatup 01/22/74 Unit 2 Trip From Approxi-2 Ne mately 20% FP - Seal Leak on 2B2 RCP caused Loss of RC Water to Reactor Building 07/2:-/72 RC Flow Greater than 100%
1 Yes 05/09/ 3 Rapid loss of Oil to I
No
~
Reactor Coolant Pump 2A1
'$0gg dB@]M$1 i
En:lesure sOconee 1, 2, 3) '
REACTOR C001. ANT SYSTEM Late Incident Unit No.
Reportable 03/27/73 Oil Spill on Reactor 1
No Pump 1B1 03/06/73 Reactor Coolant Pump 1
No 1A1 Fire 9.
Keovee Hydro (Emergency Power System)
There have been two kinds of problems with Keowee. One was administrative and the second was problems with a field flashing breaker. Both are con-sidered resolved.
The administrative controls weaknesses led to events that resulted in not having the Keovee unit available as required by Technical Specifications.
Regulatcry efforts resulted in higher controls and more formal procedures fcr maintaining the status of the units.
Since 1977. no major problems have been identified with administrative control.
I. December '77 a problem with the field flashing breaker on Keowee Unit 2 was :dentified.
This event and subsequent events were rep rted as 1.ER's.
The faul.y breaker was replaced and the problem was reselred.
A prellet with Cutler-Hacmer relays was reported tc.NRC and IES 75-04 was
- .s s u e d.
The problem dealt with the emergency power stitchin; logic system.
All Cutler-liammer relays iniclved were replaced 1 - Lvember 1975.
The 7-d' =m has been resolved.
!ie even.s involving Keowee are summarized below.
IE fellowup is discussed briefly in Inspection Reports 50-269/78-13, 50-270/78-12. 50-257/78-12, 5r.-265-/76-6, 50-270/76-6, 50-257/76-6, and 50-269/76-4.
120'EE HYDRO (EFERGENCY POWER SOURCE)
Da.e Incident Unit Nc.
~ Reportable
- 5 ".5 TE Keovee !2 Field
- 1. 2. 3 RO-269/78-14 Flashing Breaker Failed to Close i
05/10;'78 Keovee 92 Field I, 2, 3 RO-269/75'14 Flashing Breaker Failed to Close M/.! E Emergency Startup
- 2. 2. J KO-26975-l'.
of Keowee Inhibited k
g [gb[n e.f"3 M
O m
G
mm En: :sure (Oconee 1, 2, 3) '
KE0kT.E HYDRO (EMERGENCY P0kIE SOUR 2E;
.a te Incident Unit No.
Reportable 03/22/78 Keowee #2 Failed to 1, 2, 3 R0-269/78-9 Start - General Field Flashing Breaker 03/14/78 (Cutler Hacmer Relays 1, 2, 3 n?-269/78-7 Rep.) Keowee #2 Failed to Start - General Field Flashing Breaker Problem 03/10/75 Keowee #2 Field Flashing 1, 2, 3 R0-269/78-6 Breaker Failed to Close 0_/22/78 Keowee Uni't 2 Failed to 1, 2, 3 R0-269/78-3 Start Due to General Field Flashing Breaker 0:/05;'75 Keowee Unit _.2 Failed to 1, 2, 3 R0-269/78-1 Start Due to Problem k'ith Generator Field
~
'._!09/77 Keovee Uni: 2 Failed to
- . 2. 3 R0-269 ~7-29 Start Due to Preble with Generator Field
.5/17/77 Emergency lockout cf 1, 2, i R0-269/~7-17 Keowee Units During Test 1./G4/76 ES (Engineered Safe-3
'o guards) Start of Both Keowee Units During Test 0i/30/76 Keowee Unit Not Avail-
- 1. 2, 2 R0-269/76-15 able to Supply 230 KT Yellow Bus 1/16!76 Emergency Start on 1
Ne Keowee Ch. A by Button Somehow Pushed
- /09*i6 Keovee Unit 1 Tripped
- 1. 2 From Underground During Unit 2 Maintenance 9b Q,
L
[-<,+x j
En-k:sure(Oconee1,2,3) ~
KE0 WEE HYDRO (EMERGENCY POWER SOURCE)
Date Incident Unit No.
Reportable 07/01/76 Keowee Unit 2.Wouldn't 1, 3 No Operate 22 MWE Because of Air Circuit Breaker #2 Problem 06/10/76 Partial Failure to Kewoee 1, 3 R0-269/76-10 Unit 2 06/08/76 Keowee Isolated From Both 1, 3 R0-269/76-9 Overhead and Underground Feeders 06/.07/76 Keowee ACB-#1 Fai]ure -
1, 3 R0-269/76-8 Not Available to Overhea'd Line C5/26/76 Keowee Unit _1 Removed 1, 2, 3 R0-257/76-7 from Service Without Connecting Unit 2 to Underground I'.; C 5; 75 Keowee Unit 2 Failed 1, 2, 3 A0-:i9,75-13 to Start Due to Exci-tation Breaker Problem 27/25/75 One String of Keowee 2, 3 A -27; 75-13 and One S itching Station Batteries Out of Service 07/02/75 Keowee Unit 2 Became N/A A0- 25 c.' 75-8 Inoperable As Did Lee Gas Turbine Ed. ~_1. 75 Keowee Unit 1 Tripped 3
Ne on ES (Engineered Safeguards) & Didn't Restart 0-f30/75 Keowee Unit 2 Tripped 1
A0-26 9.' 75 2 ',
After Emergency Start C
'. 7 ' 7 5 Keowee Unit 1 Locked 2
A! 5-6 Out fr.~ nile Connected to Underground During Energency Start Tes:
m T\\
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n w_-e -m f
En b stre (Ocon = 1, 2, 3) '
KE0'dE HYDRO (EFERGENCY POWER SCUECE)
- ate Incident Unit Nc.
Reoortable 02/11/75 Keowee Energency Start 3
UE-287/75-1 Button in Unit 3 Control Room Not Operable O'./23/74 Trip of Keowee During 1
UE-269/70-1 Emert acy Start Tests 1/29/7',
Keovee Unit 1 Removed N/A A0-269/74-1 From Service 03/21/73 Unit i Keovee Not 1
No Available for Emergency-06/27'73 Keowee Unit 1 Tcilure 1
UE-269/73-5 to Start (Normal Start)
^
,uacrant 1_t ana. 3. ower Os cilla tio__n_
- quadrant power tilt problem was first observed at
'C' pcwer fellowing star::p after refueling on Unit 1, cycle 4.
DFC and 1D. inves-igated and mee:ings were held with IEE, NRR, E&W, and DPC.
The probler has been res:_ced. Reference reports are listed below.
117 - 1447, Oconee Unit 1, Cycle 4 - Reload Report. ': arch 1977
'.e t ter, W. O. Pa rker to E. G. Ca se, 10 77 letter, W. O. Parker to E. G. Case,11/9/77
'.e:.ter, W. O. Parker to E. G. Case,1-23-7EI J
~_et.er, W. O. Pa rker to E. G. Case, 12-14-77 Meeting in Bethesda, Maryland, NRC, PPC, and E&W
.. pcwer oscillation and a oscillating quadrant power tilt was identified on Cconee Unit 3. These subjects are discussed in IE Inspectic Reports 50-287/
75 '. 50-257/78-20, 50-287/78-26, and 5_0-287/75-31.
T.ue problems have been extensively investigated by the licensee and by n.s :casu_tants using experiments ano, analysis.
.ne resu.ts and ccnclusions are ;_blished in a report availa'le from DPC:
"$hvestigation of Low Anomalies at
.,o
. Oconee 2" (E-S010', by F. E.'.Seff
, binson, Tec.nnology Ior r.nergy corp.
in: s.
- t..
The :_E.:.'s related to these problecs a re listed belco.
i' 9
,.bt-
=4 4
. m.
g
<L 3,', Tiv 7
In: :.sure (Oconee 1, 2, 3) '
QUADR.U;T TILT.C?D POWER OSCILLATIO::
Late Incident Unit !;o.
Reportable 12/08/79 Quadrant Power Tilt 3
R0-287/78-20 Above Steady State Limit l
i 06/17/79 Reactor Quadrant 1
RO-269/79-19 Power Tilt Above Steady S. tate limit 05/07/79 Quadrant Power Tilt 1
RO-269/79-13 Beyond Error Adjust-limit l
f
{
GS/1S/78 Quadrant Tilt Above 1
RO-269/7S-18 Steady State Positive 03/06/78 Quadrant Power Tilt 1
R0-269/78-16 Beyond Limit.(Greater than 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />) 12/05'77 Uncoupled Axial Power 3
Shaping Rod 02f25/77 Rod /6 Group Drcpped 1
R0-269/77-7 Causing Runback &
Quadrant Pcwer Tilt
....,. -.: _os s e Droppec. Roc a uroup a-ra-2.u.<10 3 Tilt Exceeded limit 11.
Condenser Circulating Wa ter System
- rmally the CCW System circulates water froc.' Lake Keovce thrcugh the condenser and baci to Keovee.
Upon loss of power to the CCW pumps, an emergency line opens and the CCW continues to operate as an unassisted si.rhon for decay heat removal and emergency cooling requirements.
The valves that must cperate to the system have failed, on test a number ci tires. The prcblem is
- r.ve rt thcught to be caused due to environmental conditicns at the valve locatier..
The valves are located in a valve pit outside and dar.:pness causes electrical failure.
The item is currently being reviewed by IE.
Sur.ary of events are listed below.
l O
4 4
_r__--__------
- - - - - - ~ ~
E2i csure (Ocenea 1, 2, 3) ~
Q CONDENSER CIRCUIATING W1.TER SYSTE" Eate Incident Unit No.
Reportable 06/30/79 5 of 6 Condenser 2
No Circulating Water Emergency Discharge Valves Found Closed C7/21/77 CCW-8 Found Electrically 1, 2, 3 No Inoperable (Emergency Condition Valve) 09/22/76 CCW-8 Failed to Operate 3
No During PT 04i :C '76 CCW-8 Failed During Test 2
No 03/:C/76 CCW-8 Failed to Operate 1
No Electrically During Test
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C,/lci75 3CCW-93 and CCW-8 Didn't 3
EE-87/75-4 Open During CCW Test
' -/:7 73 Inoperability of Valve 1
CCW-8 Tarbine Euilding Flooding C: October 10, 1976, an incident occurred that resulte.i n f1 coding cf the turbine building to a depth of about one foot.
Lead resp:nsibility for e ca'_u2 tion and resolution was transferred to NRR cn Octcher 29, 1976.
The licensee's corrective action is described in R0-2S7/76-15. In addition, a standby shutdown facility is currently under construction te provide a reliable ultimate heat sink in case a flood' occurs that results in severe dstage tc the turbine building. This action is discussed in a letter from W. O. Parker to E. G. Case, dated latiruary 1,1975.
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