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CONTINu1No TRAININc--anR MID-to0P OPER.
NUMBER: cE-a0-88002-00 001-C PROGRAM:
MAINTENANCE / QC REVISION: ?
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AUTHOR:
G.R. BATE DATE:
8/8/88 APPROVED: 9/J. j7 S/h/
DATE:
g/p/pg
REFERENCES:
1.
NRC Generic Letter 87-12:
" Loss of RHR While RCS Partially Filled" 2.
GPC Response to NRC Generic Letter 87-12 3.
NOP-464 4.
LO-LP-60990-00-C
" Case Study on Loss of RJIR at Diablo Canyon" 5.
GPC Standing Order 1-87-48:
"RHR Operation with RCS Partially Filled" 6.
Procedures:
12000-Refueling Recovery a.
b.
12006-Unit Cooldown to Cold Shutdown c.
12007-Refueling Entry 5 M 'J.CS Dn ialw; o-j -_- _
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LIST OF OBJECTIVES 1.
State the initial conditions at Diablo Canyon prior to the loss of RHR cooling.
2.
Describe the ev2nts that led to the loss of RHR cooling at Diablo Canyon.
3.
Describe the possible consequences that could have resulted from a sustained loss of RHR cooling.
4.
List the instrumentation utilized at Diablo Canyon for monitoring reactor vessel level.
S.
List the instrumentation utilized at Diablo Canyon for monitoring core temperature.
l 6.
Describe actions taken at Diablo Canyon which had adverse affects on the loss of cooling event.
7.
Describe the actions to be taken by GPC to reduce the probability of a elmAlar event occurring at Plant Vogtle.
8.
List precautions which maintenance personnel must take while working on MWoe during drain-down conditione.
G E-HO-88002 001 -C.
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Initial conditicna at Diablo Canyon 1.
Mode 5 in preparation for first,refbaling 2.
Plant shutdown for 7 days 3.
Containment equipment hatch open 4.
Personnel air lock open.
S.
Containment purge in progrene 6.
Incore thermocouples disconnected in preparation for reactor vessel head removal 7.
LLRT of containment penetratione in progress 4.
RVLIS out of service due to work on PAM syteam 9.
Train 8 RHR pump operating with both heat exchangers in service and both +"aine cross-connected at 87 F 10.
No charging pumpe running (Diablo Canyon's ayaten of normal charging somewhat different than Vogtle's) 11.
RCS drained down to mid-loop in preparation for SG manway cover removal and channel heed entry.
12.
Reactor veneel vented to pressurizer i
l 13.
Reactor veneel level monitored by:
a.
Tygon tube (one inch) manometer connected to i
intermediate leg of loop 1 b.
Two electrical systems (wide and narrow range) 14.
Level controlled by balancing letdown and charging 15.
Temperature monitored by temperature elements in the RNR loop
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GE-H0 - 88002-00-001 - c PAoL317
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N00HALLY EXPECTED INITIAL CONDITIONS
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1.
The temperature of the RCS is less than 200 degrees Fahrenheit.
2.
A steam bubble is in the Pressurizer and level is maintained between l
17 po' cont and 80 percent using the cold calibrated level channel.
3.
Pressurizer pressure is 250 1 25 psig.
4.
One or two RCP's are in operation to equalize temperatures.
5.
One or both trains of RWR are in operation maintaining RCS temperature.
Flow in each operating RNR loop is 3000 gas.
6.
Charging and letdown are in operation and one train of RNR is cross connected to the letdown system.
7.
Both trains of the COPS are armed.
i 8.
SG's are at their normal level (45-55% narrow range) with a nitrogen i
blanket at 2 to 5 psig.
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9.
Safety injection signals from low steam line pressure. and low pressurizer pressure are blocked.
- 10. Both safety Injection Pumps have their power removed and all Safety Injection accumulators are isolated.
- 11. Both motor driven Auxiliary Feedwater Pumps have their control svitches in PULL-ftN.00C.
GE -HO - 80002 - OO - 001 - c -
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POTENTI' L DISTURBANCES TO THE DRAIN-00HN PROCESS A
I Svitan Potential cause
- 1. Automatic closure of RHR Instrument failure, error during suction valves from RCS hot 1sgs wintenance or testing l
- 2. Automatic oeening of Pressurizer Instrument failure, error during PORV's from COPS maintenance or testing
- 3. Automatic initiation of Emergency Instrument failure, error during Core Cooling Systes maintenance or testing
- 4. Automatic inttiatton of Aux 111ary Error during maintenance or Feedwater System testing
- 5. Automatic energtration of Error during maintenance or Pressurizer heaters testing l
- 6. Closure or opening of letdown Instrument failure. loss of pressure control valve instrument air, e. e 3r during maintenance or testing I
- 7. Closure or opening of RNR heat Control failure loss of, exchanger outlet valves instrument air, error during maintenance or testing
- 8. Closure or opening of RNR heat Instrument failure. loss of exchanger bypass valves instrument air, error during maintenance or testing
- 9. Ch4nge in charging flow Instrument failure loss of instrument air, error. during maintenance or testing l
GE-HO-t 8002-00-001 -C Page 5 of 7
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a 52 IPI-10614 I IRNR pump dascharge pressurellocal 10-1000 p.gg g 53 I IPI-10615 IRMit pump dascharge pressurellocal 30- 300 p.gg g 84 IFIS-0610 IFIS-0611 Ifect pump da scharge floes ILocal 10-1500 goe 3
% IPI-403 IPI-405 IRCS sende range pressure IGRCS 10-3000 peig 3 l
Se 1P1-408 IPI-418 IReactor vessel Pressure IEMCS 10-3000 peng g j
37 IP!-438 IPI-429-IReactor veneet pressure IENCS 10-3000 poig i I
SS IPI-0414 IPI-0415 1R65t pump discharge pressuretEMCS 10- 300 poig 3 39 IFI-41SA IFI-4194 IR>Wt to RCS cold leg floes IEDCS 10-5000 epig 3
310lFIC-415A IFIC-419A iM/A station for RNR heet IEMCS 10- 100 %
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gl11 HIC-404A IMIC-407A BR/A station for RMR heat IEMCS 10- 100 %
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leuchanger outlet valve i
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i 3198 LIHMe2 IPreneuriser level (cold) lenCS 10- 100%
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8208 FI-0469 IPftT pressure IGMCS 10- 100 peng I
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GE -HO - 88,002 - OO -OO1 - C i
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- 231' MINIMUM RWST LEVEL I
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223' RWST OUTLET N0ZZLE LEVEL I
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TOP SEAL PACKAN I
- + - 190' SOTTOM OF RCP SEAL PACKAGE I. 100' NOMMAL RCS LEVEh (1/2 LOOP PULL) 1
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- CENTEft.!W W RCP OISCHAASE PIPtNS I. 194' POW INLET P1 PINS 1
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CENTEft.!M fDet & DISCMAMSE P1P1W GE-HO-88002 001-C Page 7 of 7
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Georgia Power frv C VOGTLE ELECTRIC GENERATI TRAINifG lfSIN L*N TITLE:
CONT 1. WING TRAINING--RER MID-LOOP OPER.
NUMBER.CE-LP-88001-00k PROGRAM:
MAINTENANCE /Qc REVIS10N: 00 AUTHOR:
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G.R. BATE DATE: 8/s/es APPROVED: C}n.TS).,k DATE: g/q/gg INSTRUCTOR GUIELIES:
1.
LESSON PRESENTATION F0 PRAT--Lecture 2.
LIST OF EQUIPMENT / MATERIALS REQUIRED-Overhead Projector. Transparencies. Student Handout 3.
STUDENT EVALUATION M"lli0D-Quiz 4
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'CE-LP-88002-00 4 i
REFERENCES:
- 1.
NRC Generic Letter 87-121 - " Loss of RHR while RCS Partially Filled"-
i 2.
GPC Response to NRC Ceneric Letter 87-12 3.
NOP-464 4.
LO-LP-60990-00-C:
" Case Study.for the Loss of RHR Cooling at Diablo Canyon" 5.
CPC Standing Order 1-87-48:
"RER Operation with RCS Partially Filled" 6.
Procedures i
a.
12000--Refueling Recovery b.
12006--Unit Cooldown to Cold Shutdown c.
12007--Refueling Entry-d.
13005--RCS Draining 9
9 e
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2
- i..
Cro7 CE-LP-88002-00-C 1.
PURPOSE STATEMENT:
The purpose of this lesson is to provide the student with an understanding of the events 1 Leading up to, during, and corrective actions taken for the loss of RHR at Diablo Canyon Vatt 2 nuclear Power Plant and applicable actiors taken or to be taken to reduce the e:'ility of a similar event occurring at Plant Vogtle.
6.
LIST OF OBJECTIVES:
1.
State the initial conditions at Diablo Canyon prior to the loss of RHR cooling.
2.
Describe the events that led to the loss of RER cooling at Diablo Canyon.
/ 3.
Describe the possic".e consequences that could have resulted from a sustained loss of RHR cooling.
4 List the instrumentation utilized at Diablo Canyon for monitoring reactor vessel level.
3.
List the instrumentation utilized at Diablo Canyon for monitoring core temperature.
6.
Describe actions taken at Diablo Canyon which had adverse affects on the loss of coolfng event.
7.
Describe the actions to be taken by GPC to reduce the probability of a similar event occurring at Plant Vogtle.
8.
List precautions which maintenance personnel must take while working on MW0s during drain-down conditions.
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p, GE07 CE-LP-88002-00-C Ill.
LESSON OUTLINE:
NOTES I.
INTRODUCTION,
A.
Lesson covers following:
1.
Case study on loss of RHR cooling at Diablo Canyon"while the RCS was partially filled (37 additional events have occurred in the industry due to inadequate RCS water level).
2.
Actions taken by CPC in response to the NRC's generic letter 87-12 which questioned utilitiva to assess the safe operation of PWRs when RCS water level is drained down below the top of the reactor pressure vessel head.
3.
Precautions maintenance personnel should take when performing MW0s during drained-down conditions.
B.
Discuss Lesson Objectives CE-TP-88002-00-001 II.
PRESENTATION A.
Review of RCS/RHR/CVCS operation curing cold shutdown condition (mode 5) just prior to refueling (mode 6).
1.
Mode 5-Cold Shutdown s.
Reactor shutdown with Kaff less than 0.99.
b.
Tava less than or equal to 200 F.
2.
Mode 6-Refueling Reactor shutdown with Keff less than or equal a.
to 0.95.
b.
Ta<g less than or equal to 140 F.
~
3.
RCS CE-TP-88002-00-002 a.
All four RCPs off.
b.
PZR empty.
c.
RCS drained to a level fl mat has the hot les piping of the reactor hnif filled-(mid-loop).
4.
RHR a.
Both trains operable with at least one train operating.
4
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GE07 hP-1P-AR002~00~C lile LESSON OUTLINE:
NOTES b.,
RER inlat via at least one hot leg and returned to all four cold legs, Minimum flow requirement of 3000 gpm.
c.
d.
S' mall an'ount of flow (75 t; 120 gpm) sent into CVCS just upstream of letdown heat exchanger for continuous cleanup of reactor coolant.
5.
CVCS Normal inlet to CVCS from loop 3 cold leg, a.
b.
Three letdown orifices in service with icolation valves (LOIVs) open.
Only a small trickle of flow exists through c.
the letdown orifices since flow is dependent on differential pressure and the dp is very low in mode 5.
d.
PCV-131 controlled by PT for desired pressure.
PDP operating to maintain level by balancing e.
letdown and charging.
f.
Seal injection to RCPs injected into No. I seal and thermal barrier.
B.
Initial Conditions at Diablo Canyon prior to loss of GE-TP-88002-00-003 RHR cooling.
Obj. 1 1.
Mode 5 in preparation for first refueling.
2.
Plant shutdown for 7 days.
3.
Containment equipment hatch open.
4.
Personnel air lock open.
5.
Containment purge in progress.
o 6.
Incore thermocouples disconnected in preparation for reactor vessel head removal.
7.
LLRT of containment penetrations in progress.-
8.
RVLIS out of service due to work on PAM systems.
9.
Train B RH1 pump operating with both heat exchangers in service and both trains cross-connected at 87 F.
5
- orn, t
--- Ill.
LESSON OUTLINE:
CE-LP-88002-00-C NOTES 10.
No. charging pumps running (Diablo Canyon's system of normal charging somewhat dif f erent than Vogtle's).
11.
RCS drained down to mid-loop in preparation for SG manway cover ' removal and channel head entry.
12.
Reactor vessel vented to pressurizer.
13.
Reactor vessel level monitored by:
Obj. 4 Tygen tube (one inch) manometer cennected to a.
intermediate leg of loop 1.
b.
Two electrical systems (vide and narrow range).
14.
Level controlled by balancing letdown and charging.
- 15. Temperature monitored by temperature elements in Obj. S the RHR loop.
C.
Event Initiation Obj. 2 1.
Plant operator isolatad portion of RCP seal water return line to VCT in preparation for testing penetration for air leaks.
2.
All valves necessary for system isolation were independently verified to be closed.
, 3.,
One of the valves labeled " Valve 1" on the TP was improperly seated (operated by a reach rod).
4.
At 2043. a plant engineer opened a valve -(valve 2 -
on TP) to drain the seal water return line to the PC?T in preparation for LLRT (without nocifying the control room of the test start) then left the area.
~
5.
With valve 1 improperly seated, water from CVCS
~'l and RCS was draining into RCDT.
6.;
control room operator immediately noticas a decrease in VCT level.
me
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7.
-ABO notices and-reported increaned level in RCDT.
8.
Operators atter?ted to restore VBT level by increasing letdown flow from RHR into CVCS.
< 9.
Reactor vessel level started slowly decreasing as indicated.
I 6
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CS07 nF-LP-BB002-00-C lli.
LESSON OUTLINE.
NOTES
- 10. Optrators isolated chstging and letdown in an attempt to stop the leak,
- 11. With the loss of flow into the VCT, water level in VCT decreased rapidly since water was still draining.from VCT into RCDT at a rate of 30 spa.
12.
Reactor vessel level indicator in control room indicated level had stopped decreasing.
D.k?LossofRHRcooling 1.
At 2125 (42 minutes after engineer opened drain valve for his LLRT), control room operators noticed fluctuating amparaSe on running RHR pump.
2.
No. 2 RHR pump secured, then No. I pump started but was immediately secured due to fluctuating amps as well.
3.
RHR was lost at this point.
4.
Decay heet now began heating reactor coolant from 87 F.
5.
With loss of RHR, temperature indication of core was also lost since all incore thermocouples i
were dfsconnected.
6..
Vortexing and cavitation-was suspected as the cause of RHR motor amp fluctuation due to low level in the hot leg piping.
7.
Validity of electric reactor vessel indicators was suspect due to vortexing so A30 dispatched to check on tygon tube level inside containment.
8.,
Operators had intention of opening RER valves aligned to RWST to allow gravity fill to RCS, however, they requested a status of SG manway covsr removal to see if any personnel was in area of manway or inside of channel head.
9.
At 2138. VCT outlet valve was closed to stop VCT inventory loss.
- 10. At 2200, plant engineer opened vent valves associated with his LLRT penetration being drained and lef t the area to find HP technician to assist in LLRT.
- 11. At 2203, RHk pumps vented.
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-.m, GE-LP-88002-00-C 111.
LESSON OUTLINE:
NOTES
- 12. At 7221. No. 1 RHR pump started but still had fluctuating amps so pump was again stopped.
13.
At 2227. NOUE declared since RHR lost for more than one hour.
14.
Plant eng'ineer noticed large amount of water associated with his draining evolution.
- 15. At 2230, containment activity levels increasing I
and' air samples ordered.
E.
Restoration of RHR cooling 1.
At 2241, operators informed that SG manways not removed but some bolts had been detensioned.
2.
RWST to RHR valves were immediately opened for gravity fill into RCS.
3.
At 2250, leak path to RCDT isolated.
4 At 2254, No. 2 RER pump started and RER cooling flow established.
5.
Pump discharge temperatures rose to approximately 220 F and within 5 minutes temperatures dropped to less than 200 F.
6.
At 2258, personnel in containment reported steam venting from ruptured tygon tube on reactor vessel head vent and was then isolated.
7.
Containment evacuation was ordered.
8.
Steam leakage reported from SG manways.
9.
Decay heat had increased temperature of core from 87 F,to boiling during loss of RER.
- 10. Operators now restored plant to normal operation.
F.
Potential consequences due to loss of RHR cooling.
Obj. 3 1.
Boiling was occurring in reactor core.
2r Reactor vessel water level could have boiled dry and caused core damage with possible fission product release to containment atmosphere.
3.
Since air lock and equipment hatch open, fission products could have reached the environment.
8
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GE-LP-88002-00-C Ill.
LESSON OUTLINE.
NOTES G.
Detrimental Effects During Event 1.
Outage activities not coordinated with mid-loop operation planned for a lengthy period of time.
2.
Equipment hat'ch open during mid-loop operation.
3.
Only core temperature indication was from RER loop.
4.
Operators estimated heatup rate at 1 F/ min but was actually 2.7 F/ min.
5.
Procedural deficiencies were discovered.
6.
Shift briefing did not mention LLRT started, however, it was approved.
7.
Plant engineer did not inform control room of LLRT start.
8.
Work orders that have a potential of draining RCS should noc be performed when operating at mid-loop.
9.
Poor communications existed.
s 10.
Poor design of reach rod for improper seated valve.
11.
An ALERT should have been declared instead of NOUE.
H.
Plant Vogtle's action to reduce possibility of similar Obj. 7 event as Diablo Canyon loss of RHR.
1.
Generic letter 87-12 from NRC asked utilities various questions on how they planned to ensure safe operation of PWR plant during mid-loop operation.
2.
GPC's responaa to NRC--not all items discussed, only,those that are of interest to maintenance personnel, a.
QUESTION 1: Circumstances when plant would enter into drain-down condition?
b.
RESPONSE 11 1)
Refueling operations for head removal.
-2)-
Maintenance activities for various componeues such as RCP seal replacement.
SG tube inspections / replacement, repair of RCS boundary-valves, etc.
9 4
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GE-LP-88002-00-C Ill.
LESSON OUTLINE:
NOTES c.,
QUESTION 2: Conditions which plant would be in just prior to drain-down?
d.
RESPONSE 2: Discuss initial conditions briefly which are listed as appendix A of response letter.
GE-TP-88002-00-004 e.
QUESTION 3: Control systems and interlocks that could diaturb the drain-down process?
f RESPONSE 3: Discuss control systems and GE-TP-88002-00-005 interlocks which are listed as appendix C of response letter.
1)
If MWO issued for those listed systems, ensure supervision is aware of the consequences at mid-loop.
2)
If work has to be performed on any of these systems during mid-loop, care should be exercised to ensure procedural compliance is followed and a questioning attitude maintained throughout as any error could have an affect on reactor vessel level.
3)
If possible, no work should be performed which could affect reactor vessel level during mid-loop, g.
QUESTION 4: Equipment status change coordination?
h.
RESPONSE 4:
1)
Changes to status of equipment for maintenance, testing, or operations which affect plant conditions must be authorized by the shif t supervisor.
~
2)
The above statement is true for all
' modes.
3 1.
QUESTION 5: RCS overpressure protection?
j.;
RESPONSE 5:
1)
Protection from overpressure when reactor vessel head is in place during modes 4, 5, and 6 is provided by the COPS.
2)
If pressure is too great for the existing temperature, power operated relief valve (PORV) lifts to PRT.
10
"rni GE-LP-88002-00-C Ill.
LESSON OUTLINE:
NOTES k.,
QUESTION 6: Time required to replace containment equipment hatch if open?
1.
RESPONSE 6:. Replacement takes three to four hours and an additional 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> i
FOR LLRT.
J m.
QUESTION 7:
Instrumentation and alarms provided during RCS partial fill?
n.
RESPONSE 7:
1 1)
Permanent plant instrumentation a)
Discuss instruments listed in~ Table 2 of GPC response letter.
GE-TP-88002-00-006 (1) New procedure will require a minimum of two incore thermo-couples operable any time head installed ~and level below top head flange.
(2)
If head is to be removed.
disconnection of thermocouples is to be delayed until last possible moment and reinstalled at first opportunity after head replaced, b)
Alarms (1)
"RHR Pump Motor Overload" annun.
(2) "RHR Pump Discharge High Pressure" annun.
(3) No temperature alarus sanunciated in control room for use during 7-.
mid-loop operation.
T 2)
Temporary connections, piping, and instrumentation.
a)
One inch tygon tube connected to RCS at loop 1 intermediate. leg and pressurizer steam space.
(1). Care should be taken not to step on tygon tubing run and report any defects, kinks, twists, or air binding to supe rv! s ion.
11 L
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crn7 CE-LP-88002-00-C Ill.
LESSON OUTLINE:
NOTES (2) Tubing will have continuous slope to minimize air entrapment.
(3) Tubing will be protected by physical barriers when routed l
through traffic areas.
(4) Tubing will be positively 3
identified along route.
(5) - Tubing will. run upward along containment wall adjacent to elevation marks.
(6) Discuss elevation marks and GE-TP-88002-00-007 associated RCS component descriptions.
(7) Operations will assign a continuous watch station at tubing during mid-loop operation and v111 valkdown tubing every four hours to ensure tube is free of kinks. etc.
b)
RVLIS is available but not accurate enough for controlling level within a tight band of 6 to 12 inches.-
c)
Additional instrumentation planned but not part of letter to NRC, (1) Level instrument connected to one of RCS flow tape beneath SG and to RTD bypass manifold then wired to SI Accumulator-Tank level channel indicator in control room (channel L-952).
(2)
Level instrument connected across hot leg pipe with a 30-inch span.
d)
Installations will be part of MWO process.
o.
3 QUESTION : Pumps required to be operable to control RCS inventory?
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12
CE-LP-88002-00-C
~
Ill.
LESSON OUTLINE:
NOTES p.
RESPONSE 8:
1)
A mini. mum of one of three CVCS charging pumps is required to be operable, therefore, two pumps can be removed f rom service for maintenance.
2)
Both RHR pumps required to be operable in mode 6 with water level less than 23 feet above the RV flange or in mode 5 with the RCS loops not completely filled, a)
One train may be inoperable for up to two hours for surveillance testing.
b)
One. train may be deenergized for one hour provided dilution of RCS is not permitted and core outlet temperature is at least 10 F below saturation, q.
QUESTION 9: Training provided to affected personnel during RCS partial fill?
r.
RESPONSE 9:
1)
Haintenance Operation Quality Assurance t
i Program /MWO lesson details use of MW0s.
2)
Safety and Admin Controle lesson details l
proper use of admin, maintenance, and EP procedures.
3)
Equipment Clearance and Tagging lesson details personnel's responsibility i
l according to clearance and tagging j
procedure.
s.
QUESTION 10:
What are planned changes and when i
are they scheduled to be incorporated?
l t.
RESPONSE 10:
1)
Kinimum level during mid-loop will be 188 ft. instead of 187 ft. 6-inches to give_a one foot margin to mid-loop (short teru).
2)
If RER is lost for more than one hour or temperatures are greater than 200 F, an ALERT will be declared and containment closure verified (short term).
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LPSSON OUTLINE NOTES l
3)
Work will be limited that hcs potential to decrease RCS inventory when level l
below top head flange (short tera).
4)
Evaluation to be made to install structure aro'und equipment hatch to allow placement of polyethylene curtain over opening (long t e rm).
3.
Precautions for maintenance personnel during mid-loop operations.
Obj. 8 a.
Maintain questioning attitude toward MW0s.
b.
Any unusual or suspicious evolutions should i
be reported to supervision, such sa 1)
Unexpected sound of water flow.
2)
Steam leaks.
3)
Air hisses.
c.
WATCH OUT for tygon tube.
i III.
SUMMARY
1 l
A.
Review lesson objectives in preparation for quis.
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LIST OF OBJECTIVES l
1.
State the initial conditions at Diablo Canyon prior to the loss of RNR cooling.
2.
Describe the events that led to the loss of RHR cooling at Diablo Canyon.
3.
Describe the possible consequences that could have resulted from a sustained loss of RNR cooling.
4.
List the instrumentation utilized at Diablo Canyon for monitoring reactor vessel level.
5.
List the instrumentation utilized at Diablo Canyon for monitoring core temperature.
I 6.
Describe actions taken-at-Diablo Canyon which had adverse affecte on the loss of cooling event.
7.
Describe the actions to be taken by GPC to reduce the probability of a similar event occurring at Plant Vogtle.
8.
List precautions which maintenance personnel must take while working on MWoe during drain-down conditione.
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4 In,itial conditione at Diablo Canyon 1.
' Mode 5 in preparation for first refueling 2.
Plant shutdown for 7 days 3.
Containment equipment hatch open 4.
Personnel air lock open S.
Containment purge in progress 6.
Incore thermocouples disconnected in preparation for reactor vessel head removal 7.
LLRT of containment penetrations in progresa 8.
RVLIS out of service due to work on PAM syteme 9.
Train B RHR pump operating with both heat exchangere in service and both traine cross-connected at 87 F 10.
No charging pumps can. ting (Diablo Canyon's system of normal charging somewhat different than Vogtle's) 11.
RCS drained down to mal-loop in preparation for SG manway cover removal and channel head entry.
12.
Reactor vessel vented to preneurizer 13.
Reactor vessel itvtl monitored by a.
Tygon tube (one Anch) manometer connected to latermediate leg of loop i b.
Two electrical systeme (wide and narrow range) 14.
Level controlled by balancing letdown and charging 16.
Temperature monitored by temperature elementa in the RRR loop GE-TP-88002-00-003
. NODWALLY EXPECTED INf7fAL CONDITicNS 1.
The temperature of the RC$ is less than 200 degrees Fahrenholt.
2.
A steam bubble is in the Pressurizer and level is maintaine 17 percent and 80 percent using the cold calibrated level channel.
3.
Pressurizer pressure is 250 1 25 psig.
4.
One or two RCP's are in operation to equalize temperatures.
5.
One or both trains of RNR are in operation maintaining RCS, temperature.
Flow in each operating RNA loop is 3000 gem.
6.
Charging and letdown are in operation and one train of RMR is cross connected to the letdown system.
~
7.
Both trains of the ' COPS are armed.
I 8.
blanket at 2 to 5 psig.$G's are at their normal level (45-551 narro I
9.
Safety injection signals from low steam line pressure. and low L
pressurizer pressure are blocked.
- 10. Both Safety Injection pumps have their power removed and a Injection accumulators are isolated.
- 11. Both motor drivon Amal11ery Feedwater M have their switches in MA.L-M.
control t
I GE-TP-88002 004
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POTENint DISTURBAM(ES TO THE ORAIN-DOWN Pe0 CESS I
Sviten Potential Cauns
- 1. Automatic closure of RHR Instrusent failure, error during suction valves from RCS hot legs maintenance or testing
- 2. Automatic opening of Pressurizer Instrument failure, error during PORV's from COPS maintenance or testing
- 3. Automatic initiation of Emergency Instrument failure, error during Core Cooling System maintenance or testing
- 4. Automatic initiation of Auxiliary Error during maintenance or Feedwater System testing
- 5. Automatic energization of Error during maintenance or Pressuriter heaters testing
- 6. Closure or opening of letdown Instrument failure loss of pressure control valve instrument air, error during maintenance or testing
- 7. Closure or opening of RHR heat Control failure, loss of exchanger outlet valves instrument air, error during maintenance or testing
- 8. Closure or opening of NIR heat Instrument failure loss of exchanger bypass valves instrument air, error during -
atintenance or testing
- 9. Change in charging: flow Instrument failure loss of instrument air, error. during maintenance or testing G E-TP-81002-00-005
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8 hPI-0601,kPI-0602 IRNR pump suction pressure ILocal 10- 300,,ag g
31 82 IPI-10614 I 18168t pump-discharge preneurellocal 10-1000 p*19 I 33 A IPI-10615 IftHR pump discharge, pressurellocal 10- 300 pegg g 34 IFIS-0610 IFIS-0611 Iftet pump st ocharge f' lose ILocal 10-1500 goe 3
35 iPI-403 iPI-405 iftCS wide range pressure iGMCS 10-3000 p tg g 36 lPI-400 1P1-418 fftsactor vessel pressure IEDC S 10-3000 peng 3 37 IPI-430 iPI-428-Iftsactor vessel pressure IENICS 10-3000 peng a SS iPI-0614 IPI-0615 1RDet pump discharge preneurelEN4C3 10- 300 pelg g 39 1F1-6184 IFI-6194 IMDWt to f4CS cold leg flees IENCS 10-5000 gWe g
880lFIC-61SA IFIC-619A iM/A station for RHR heat IGMCS 10- 100 2 3
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I leuchanger hypese valve I
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l SillHIC-606A iMIC-6074 IM/A station for RHR heat IEWECS 10- 100 %
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I leuchanger outlet valve i
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a82tTR-0612 ITR-0613 l Pen recorder for RHR heat leMCS 10- 400 degF 3 4
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leuchanger inlet er cutlet i
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I Itemperatures I
I 3131FI-61SS IFI-4199 lease as 5 IPSDA,PSDel0-5000 opg I
3141FIC-6103 IFIC-4193. lease es e IP904,PSDSlo-100 %
I 315tHIC-6068 IMIC-6073 lease es 7 IPSDA PSDSto-100 1 8
3ielTI-4048 4TI 6 1899 heet enchanger outlet iPSDA,PSDS150-400 degF 4 3
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iteoperature I
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3171LT-1311 ILT-1321 Imeester veneet level leMCS 10- 120 %
I g18I(werasue3I(werteus3iCare Sait Thermecouples lERF i0-2300 degF 8 3
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IM per. train - 50 total Icesputer i I
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3198 LI-0442 lProeeuriser level (cold) leMCS 10- 100%
- I 3201 PI-0469 IFRT prcoeure iENICS I0- 100 pe19 8 4
GE -TP-88002 - OO -006
E ELEVAtl0N C.OMMNENT 281' MINIMUM RhsST LEVEL l
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223' RWST OUTLET NOZZLE LEVEL i
221' TOP OF STEAM GENERATOR U-TUSES I
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- PRESSURIZER SURSE LINE NOZZLE LEVEL 1-19 4' RV FLANGE - 193
- TW OP RCP SEAL P N l
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SOTTOM W RCP SEAL PACKAN l - 1 M '
POW 4AL lES LEVEL (1/2 L5 p P1A.L) l
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CENTERLINE OP RCP D!SCHAMSE PIP 1M5 g
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CENTERLIm RHR PUMP OIscManes P1PtMe GE-TP-88002-00-oo?
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