ML20212Q219
| ML20212Q219 | |
| Person / Time | |
|---|---|
| Site: | Big Rock Point File:Consumers Energy icon.png |
| Issue date: | 08/27/1986 |
| From: | Frisch R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8609040090 | |
| Download: ML20212Q219 (22) | |
Text
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W Consumers Power moissanus n9EMAW5 PResRE55 oeneral officas: 1945 West Parnait Road, Jackson, MI 49201. (517) 788 0550 August 27, 1986
- Director, Nuclear Reactor Regulation US Nuclear Regulatory Commission Washington, DC 20555 DOCKET 50-155 - LICENSE DPR BIG ROCK POINT PLANT -
ADDITIONAL INFORMATION SUPPORTING ALTERNATE SHUTDOWN SYSTEM TECHNICAL SPECIFI-CATION CHANGE REQUEST Consumers Power Company submitted an Alternate Shutdown System Technical.
Specification Change Request dated September 30, 1985. This submittal was subsequently superceded by our March 4 and April 21, 1986 submittals. As a result of preliminary NRC review of our initial submittal, a concern was raised over our proposed 60 day Limiting Condition for Operation on the #1 Control Rod Drivo Pump. To resolve this concern, we committed to the Big Rock Point Senior Resident Inspector to perform an analysis which would determine the feasibility of modifying #2 Control Rod Drive Pump power supply and/or change the proposed Limiting Condition for Operation on the #1 Control Rod Drive Pump. This analysis has been completed and is being submitted as additional supporting information for the Alternate Shutdown System Technical Specification Change Request.
Probabilistic Risk Assessment methods were used which included event tree and fault tree analysis. The Big Rock Point PRA was used as a source for system and equipment inilure data which was used in the quantification of the trees.
The results of the analysis show that there is a minimal change in the calcu-lated core damage probability for reduction in the proposed #1 Control Rod
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Drive Pump Limiting Condition for Operation from 60 days to 14 days. The results also indicate that the cost benefit of modifying #2 Control Rod Drive Pump power supply (in excess of $10,000/manrem saved) does not justify a modification.
The greatest inpact to the primary system makeup reliability (and thus the core damage probability) comes from taking credit for an operator manually opening the redundant core spray valves and using the diesel fire pump to supply water to the primary system. This makeup source is completely separate from the control rod drive / emergency diesel generator supply and therefore not OC0886-0128-NLO2 8609040090 860827 PDR ADOCK 05000155 P
Director, Nuclear Reactor Regulation 2
Big Rock Point Additional Information - Alternate Shutdown System TSCR August 27, 1986 dominated by the same failures (namely the emergency generator diesel failure rate and the operator error associated with aligning the rod drive pump (s) to the diesel generator). Furthermore, the current procedure giving the operator guidance in responding to a fire (EMP3.10) has in place statements regarding opening these valves.
Based on the results of this analysis, no changes are planned to be imple-mented to the current proposed #1 Control Rod Drive Pump Limiting Condition for Operation or the #2 Control Rod Drive Pump power supply scheme.
hA Ralpt R Frisch Senior Licensing Analyst CC Administrator, Region III, USNRC NRC Resident Inspector - Big Rock Point Plant Attachment l
OC0886-0128-NLO2 l
l
4 ATTACHMENT Consumers Power Company Big Rock Point Plant 4
Docket 50-155 1
ANALYSIS OF AN ALTERNATE POWER SUPPLY TO THE #2 CRD PUMP IN CASE OF FIRES August 27, 1986 i
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f 19 Pages OC0886-0128-NLO2
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ANALYSIS OF AN ALTERNATE POWER SUPPLY TO THE #2 CRD PUNP - IN CASE OF FIRES
SUMMARY
This analysis was performed to provide a cost / benefit analysis of a proposed modification to the #2 CRD pump power supply.
The analysis attempts to weigh the effect of several options available to provide primary coolant inventory make-up in the event of a fire.
These options include:
1.
' Switching the #2 CRD pump power supply to the #1 pump power supply whenever the #1 pump is out for maintenance. This is considered the lowest cost pump power supply modification.
2.
Providing for a remote switch over capability from the equipment lock, such that the #2 pump can be powered from the emergency diesel whenever needed.
3.
Changing the current proposed, 60 day Limiting Condition of Operation on the #1 CRD pump to 14 days.
4.
Use of the diesel fire pump to provide make-up through manually opened redundant core spray valves M07070 and M07071.
To begin the comparison of the options, a base must be established. The base used was the plant "as is."
The fire event tree was updated and re-quantified to provide a base-line core damage probability. The fire event tree is presented in Figure 1 (Page 10). Sequences for which primary system make-up is important are summarized in Table 1 (Page 14). As part of this base-line, a separate analysis was performed to determine the amount of time the CRD pump and EDG need to be run to keep water level above the low reactor water set point. A summary of the results of this analysi.* is presented in Table 2 (Page 15).
With the base-line core damage known, the relative affects of the modifications on the core damage probability can be calculated.
(The change in Primary System Make-Up Reliability was used rather than the core damage probability, as they are prcportional.)
RA0786-0150A-BQ01
e Page 2 RESULTS The following lists the options in decreasing affect on the Primary System make-up reliability (most impact to base line).
OPTION PCS MAKE-UP UNRELIABILITY (4)
FPS and Core Spray 0.002 I
9 (2) Remote Switchover of #2 CRD Pump 0.153
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(1) Equipment Lock Switchover of #2 Pump 0.154 (3) 14 day LCO on #1 CRD Pump 0.155 i
Base-line #1 CRD Pump only 0.157 The major contributors to PCS make-up reliability for Options 1,2,3 and the Base-line are the emergency diesel generator and the human error factor, which accounts for the great similarity amoung the values.
Conclusion The greatest impact to primary coolant make-up reliability comes from taking credit for a system which is completely separate from the control rod drive make-up system, including associated condensate supply equipment and power supplies.
Therefore little benefit is gained from the modifications allowing the #2 control rod drive pump to be powered by the #1 control rod drive power supply circuits.
i Reduction of the Limiting Condition of Operation (LCO) from 60 days to 14 days also provides little benefit to the primary coolant system make-up reliability.
Detailed Analysis To assess the impact of installing equipment necessary to run the #2 control rod drive pump from the emergency diesel generator, thru the #1 pump alternate i
shutdown system circuitry, the change in core damage probability must be determined (or primary system make-up unreliability can be used).
A somewhat simplified fault tree is shown in Figure 2 (Page 13) representing two methods of providing make-up water to the primary system. One method is thru the control rod drive pumps powered by the emergency diesel generator.
The second method is thru the redundant core spray valves M07070 and M07071, l
with water from the fire protection system. The valves for this method must i
be manually opened following fires that disable power and control circuitry.
j No credit was taken for the control rod drive booster pump as a means of j
providing make-up water.
It should be noted that this pump is designed to RA0786-0150A-BQ01
a a
Page 3 i
provide approximately 100 gpm at approximately 100 psia discharge head, has provisions for being powered through the alternate shutdown system and by itself could be considered redundant to the CRD pumps once primary system pressure has been lowered by main condenser or emergency condenser operation.
The quantification was determined assuming that the only power supply to the rod drive pumps is the emergency diesel generator, and that only the diesel fire pump is available for core spray water.
Also, the 5 hour5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> mission time for the emergency diesel generator and the control rod drive pump was used for all sequences (no credit was taken for 2
shorter mission times associated with low PCS leakage or MS1V closure sequences).
i The control rod drive out for maintenance value was assumed to be connected with a 60 day LCO. This assumption was made because there is currently no LCO on the pump and the impact of a 14 LCO was requested.
It is assumed that with the LCO being reduced, the out for maintenance value will also be reduced proportionally.
The different values used for the quantification are listed in Table 3 (Page 16).
- 2 CRD PUMP POWER SUPPLY OPTIONS Option #1 This option, for which a cost estimate is included, was felt to be the lowest cost option. This modification would involve swiaching over the #2 pump power supply cables to the #1 pump power supply cables whenever the #1 pump is taken out of service. The #2 pump could then be powered from the emergency diesel generator in case of a fire.
Problems with the modification include the confusion of running the #2 pump from the #1 pump controls, and only being able to power the pump from the EDG when the #1 pump is taken out of service.
If the #1 pump were to fail to run,
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an operator would (if he could) go into containment to provide the switchover, i
The modification is, however, relatively low in cost.
Option #2 This option would provide for remote switchover of the pumps from the equipment lock area.
In this way, the #2 pump can be powered by the EDG, should the #1 pump fail to run any time during the fire sequence. The modification would
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involve running cables from the #2 pump to the equipment lock area, a new l
penetration, and several transfer switches (one of which may need to be remote controlled). This option is assumed to cost at least three times that of Option #1.
The major problem associated with this modification is the relatively high cost of the equipment.
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RA0786-0150A-BQ01
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CALCULATIONS NEEDED FOR PCS MAKE-UP OUANTIFICATION EMERGENCY DIESEL GENERATOR FAILURE FTS + OFM + FTR(5 HOUR MISSION TIME) 1.79E-3 + 3.OOE-3 + (1.97E-2)*5
.1194 CONTROL ROD DRIVE PUMP FAILURE - 2 PUMPS,60 DAY LCO
(#1 OFM)*(#2 FTS + #2 FTR) + #1 FTS + #1 FTR (3.17E-3)*(3.E-4+(1.91E-4)*5) + 3.E-4 +(1.91E-4)*5 1.3E-3 CONTROL ROD DRIVE PUMP FAILURE - 1 PUMP,14 DAY LCO
- 1 OFM(14/60) + #1 FTS + #1 FTR (3.17E-3)*(14/60) + 3.E-4 + (1.Y1E-4)*5 1.99E-3 CV-4090 FAILS TO ALLOW WATER TO CRD PUMPS FTO + FTRO 1.OE-3 + (1.01E-6)*5 1.OE-3 DIESEL FIRE PUMP FAILS TO SUPPLY WATER FTS + FTR (5 hrs) + OFM + HRA 3.06E-3 + (2.E-5)*5 + 1.33E-4 + 1.E-3 4.3E-3 FAILURE TO SUPPLY FIRE WATER AS PCS MAKE-UP DFP + VALVE FTO + HRA 4.3E-3 + 1.OE-4 +.0075
.0116 BOTH CRD PUMPS POWERED BY EDG, REMOTE SWITCHOVER
(#1 OFM + FTS + FTR)*(#2 FTS + FTR)
(3.17E-3 + 3E-4 + (1.91E-3)*5)*(3E-4 + (1.91E-3)*5) 1.28E-4
a 5
CALCULATION OF PCS MAKEUP UNRELIABILITY VALUES CASE 1
- 1 PUMP DN EDG W/ CORE SPRAY (CV4090 + EDG + CRD + HRA)*CS
(.157)*(.0116) 0.002 CASE 5 BOTH PUMPS CAPABLE OF BEING POWERED FROM THE EDG W/ REMOTE SWITCHOVER CV4090 + EDG + CRD + HRA 1.OE-3 +.1194 + 1.28E-4 +.0323 0.153 l
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e COST BENEFIT ANALVSIS THIS SECTION IS INCLUDED TO DETERMINE THE COST BENEFIT OF PROVIDING ALTERNATE SHUTDOWN CAPABILITIES FOR THE #2 CRD PUMP.
MODIFICATIONS: WOULD HAVE TO PURCHASE AND INSTALL A DISCONNECT SWITCH, A TRANSFER SWITCH AND CABLE.THE SETUP WOULD BE AS SHOWN:
TRANSFER DISE0WNECT TKANSFER WITCH SWITCM SWITC.M BUS 2A g
TEMrotAn CABLE NZ CRD W I CRD Eub BuslA PUMP PUMP THERE ARE A LOT OF DIFFERENT METHODS TO ACCOMPLISH THE SAME END RESULT.
SUCH AS TWO TRANSFER SWITCHES,HARD WIRING. ECT.THE METHOD ABOVE WAS CHOSEN TO MINIMIZE COSTS.IT IS FELT THAT TWO DISCONNECTS (CHEAPER)
WOULD NOT BE ACCEPTABLE DUE TO THE POSSIBILITY OF SHORTING BUS 1A TO BUS OA.THEREFORE A TRANSFER SWITCH 15 UTILIZED.
NOTE THAT THIS SETUP WOULD INVOLVE RUNNING THE NUMBER O PUMP FROM THE NUMBER 1 NORMAL POWER SUPPLY AND CONTROLS,WHICH MAY CREATE A SIGNIFICANT AMOUNT OF CONFUSION FOR THE OPERATORS.ALSO NOTE THAT THE CRD PUMP CIRCUIT 3 ARE CONSIDERED CLASS 1E AND SEISMIC TO BE CONSISTANT WITH THE ALTERNATE SHUTDOWN MODIFICATIONS.
PARIS ESTMATED COST LABOR TRANSFER
$30,000 150,000(EST)
SWITCH DISCONNECT J20,000 SWITCH CABLE /
110,000 TERMINALS CABLE RECPTS 110,000 SUB TOTAL 170,000 CONTINGENCY 17,000 TOTAL 177,000
+
LADOR =
t170,000 **
- NOTE: THE GhAND TOTAL DOES NOT INCLUDE MAN-HOURS FOR THE FACILITY CHANGE PACKAGE OR THE EXTENSIVE FROCEDURE CHANGES AND TRAINING
COST DENEFIT CALCULATIONS ES'iIMATED COST T130,000 CORE DAMAGE-ORIGINAL 5.OE-5 FOR SEQUENCE FF,MYC PCS MAF EUP UNRELI ABILITY 0.157 DASE CASE PCS MAVEUP Ur4 RELIABILITY 0.154 WITH MODIFICATION CHANGE IN PCS MnUEUP O.003 CHANGE IN COHE DAMAGE (CD)+tPCSMU/PCbMUI. n can 9.6E-7 PUFLIC ESIINAIED DOSE (D,)
600,GOUmrem CONI AINMI.NI FAILURE 1.O PRCPAli! LILY YEAhS LEFT IN LICENSE 18 COSI OF THE MODIFICATION (CD)*(CONT FAIL PkuB)*(D,.)*(YEARS)
CUSI BENEFI'l
=
$100.000
=
( 9. 6E-7 ) * ( 1. O) * ( 600,000) * ( 18) 112,500/manrom
=
THLHEFORE THE MODIFICATION IS NOT COST EFFECTIVE.
Page 8 Results The results are shown in Table 4 (Page 17). They indicate that for an in-containment switchover of the control rod drive pumps, no improvement is realized by the modification. Due to the type of modification, i.e.. switching the #2 pump when the #1 pump is out of service, the switch must be done every time the #1 is out, requiring " normal" plant operations using the #2 pump on the #1's circuitry.
If, on the other hand, an external containment switchover is possible, the #2 pump can be powered anytime the #1 is either out for maintenance or fails to run (even when containment is inaccessible). This modification does show a significant benefit when control rod drive pump reliability is looked at.
However, any benefit gained by adding the #2 pump is tempered when human error and the diesel generator are included. This tempering shows up when the primary coolant system make-up reliability is looked at.
In the four cases where the emergency diesel generator is used, the PCS aske-up unreliability does not differ significantly (cases 1,2,3, and 5).
In case #4, a totally separate make-up system was analysed, that being manus 11y opening the redundant core spray valves (M07070 and M07071) and using the diesel fire pump for aske-up water. This method does not rely on the emergency diesel generator nor the control rod drive pumps. The fire water thru core spray was chosen because, at the point make-up is needed, the primary coolant conditions are approximately P=40 pois and liquid level of 32 feet (1 foot above low reactor water level). These values were taken from the one-loop emergency condenser cooldown with an open MSIV, and a 10 sps water leak (
Table 2. Case #4). The primary systes pressure is well below the pressure point for core spray actuation (approximately 100 psia).
Should the recommendation be made to improve the CRD aske-up unreliability factor in the PCS unreliability value, credit should be taken for the CRD booster pump, which may be able to supply more water to the PCS at reduced pressures than the CRD pump.
Conclusions The following can be concluded from this analysis:
1.
The primary coolant system make-up unreliability, with the #1 CRD pump powered from the EDC, and no credit for core spray, is dominated by the EDC failure rate and the human error deficiencies associated with wiring the #1 CRD pump to the EDG.
2.
The PCS make-up unreliability with either pump powered from the EDC, and no credit for core spray, shows a marginal improvement. The value is still dominated by the EDC failure rate and the human error deficiency.
3.
The PCS make-up unreliability with a 14 day LCO on the #1 CRD pump, with no #2 pump capabilities and no core spray, shows a marginal improvement, the value still being dominated by the EDC and the HRA.
RA0786-0150A-BQ01
Page 9 4.
The PCS make-up unreliability with the #1 pump on the EDG and credit taken for the core spray make-up shows a significant improvement.
5.
Due to the minimal core damage probability reduction that would be realized by adding switch over capabilfties to the #2 CRD pump, no change should be made to the existing circuit y, and if necessary credit can as taken for the CRD booster pump.
6.
The cost-benefit for the low cost option (Option #1) shows that the modification does not provide a significant benefit to the health and safety of the public to justify the cost.
There is only minimal improvement in the ability to maintain the core covered following a fire through use of the second CRD pump or by reducing historical maintenance outage rates for the first CRD pump by imposition of LCOs. The basic reasons are that make-up requirements following a fire are minimal, making the second pump available or minimizing maintenance does not address the most significant sources of make-up unavailability, and installed plant equipment exist thst are available 4fter a fire which are independent to the CRD make-up train and pro $ide redundancy that a second CRD pump or reduced maintenance does not.
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RA0786-0150A-BQ01
10 FIGURE 1 FIRE EVENT TREE FIRE RPS Ff Fas M
Ev i
Z Em Y
C 1
- SEE TREE 1A **************
8 *************
3 9 *******
4 7*
]
2*
- FfMYC 10 *******
6 4 *
- FfMEmC 6*
13 *************
8 14 *******
9 3*
12 *
- FfMIYC 11
- 15 ******* 11 1
- 5*
oo*****
- FfMIEmC 16 ************* 13 17 ******* 14
- FfMIZYC e
10 ******* 16
- FfMEvC
- FfFas
- ATWs t
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-c.
11 EVENT TREE 1H MAIN CONDENSER COOLDOWN I
2 Ev Y
Em C
- 1a 5a ***************** 2a 6a ******* 3a la
- 4a
- oo*********
- Ff!EmC 3a
- 7a ******* 5a
- FflYC 2a
- Ba ******* 7a
- Ff!EvC 9a ******* 9a
- Ff!ZC
EVENT HEADINGS FIRE THE INITIATING FIRE FREQUENCY FOR A FIRE IN THE ROOM BEING OUANTIFIED.
RPO AUTOMATIC REACTCR SCRAM Ff THE PROBABILITY THAT TnE FIRE COULD AFFECT SOME SAFETY SYSTEMS AND THE PROBABILITY THAT ALL SAFETY SYSTEMS ARE AFFECTED i
Foo THE ACTIVATION OF THE ALTERNATE SHUTDOWN BUILDING WHICH INCLUDES TRANSFER OF THE EMERGENCY CONDENSER OUTLET VALVES j
M THE MAIN CONDENSER AS A HEAT SINK INCLUDING SOME IMPORTANT ASSOCIATED SYSTEMS (FEEDWATER. CONDENSATE.& CIRCULATING WATER)
Ev EMERGENCY CONDENSER OUTLET VALVES MO-7053 h MO-7063 1
PCS ISOLATION BY A COMBINATION OF THE STOP VALVE OR TURBINE 1
4 ADMISSION VALVES AND THE BYPASS OR BYPASS ISOLATION VALVES i
Z PCS ISOLATION BY THE MS!V (MO-7050)
Em EMERGENCY CONDENSER MAKE-UP FROM EITHER THE DEMIN WATER SYSTEM i
OR THE FIRE PROTECTION SYSTEM Y
PCS INVENTORY MAKEUP BY EITHER THE CONTROL ROD DRIVE SYSTEM OR i
THE FEEDWATER SYSTEM C
AUTOMATIC OR MANUAL ACTUATION OF THE RDS/ CORE SPRAY SYSTEMS
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Rua-TREE Fc1e. Peanday Un.nor In%NitHty f%EuP i
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, _ _ _ _ _ _. _, _, _ _... _ _ _ _ _ -. _. _.. ~. _... _. _ _. _....,, - - -. _. _.,. _. _ _ _ _ _. _.... _.... _ _...., _ _ _ _ _ _ _ _ _. _ _ _ _ - _ _ - _ _ _ - _ _ _.
F\\C,URE 3
13a MONITORS OMIT 5 MONITORINb 0.0034 PCS LEVEL N PCS LEVEL READS LEVEL RERDING ERROR 0.004 CORRECT PCS LEVEL, HIGH PERFORMS SWP OmlSSON OF SRT 0.00b EMr 3.10.5.3 B EMP 3.10.b.16 SELECT 5 SELET. TION E.2 tor 0.001 TRS-1901 rRS 14on PERFORMS STEP OMISS16N OF SRP 0.00b EMP3.10.5.3C EMP 3. AS.3C SEl.ECTS set.ECDON ERROR O.000'l DISC-1991 Olst - 194I O MI5510M 0F OSE OF 50P-18 0.00k SELECT 5 ISa 150' 4.Z E-9 h
SELEG5 SB
\\Sb' l.L E-10 s
th SELECTION ERROR 3.0 E-1 C.ONT K01. SWITCH s N lha 7 5ELELTION ERROR 20 E-8 y BUTTON
- s OMISSION 0F STEP 0.006 E MP 3.10.6.3 E SELECTION ERROR 0 004 TRS-199Z O. 0M 3
' 15a SELECTION ERROR. UWTROL SWITO4 0 001 the' FAILS Tb n6Ti(.E DIESEL STMilnb 0.000)
ISb SEACn0N ERROR PUSH BUTTON 0.001 15hf FRil5 tb NOTRE DIESEL STWindh 0 0000\\
11e 5Et&CiaN ERROR.CDNWOLSWft.Il 0.001 lbo FAILS TO NOTX.E OlESEL STBRHW.i 0 000t 17 SELEC.110N ERROR, N5H BUT10N 0 002.
Ilo FALLS To NoT)CE DIESEL 5%RTINb O.00001 H R A EVENT TREh CONTROL K0b DRWENMP POWERED FROM THE E MER6 ENC 9 0IESEL C,E9EPAToR 1
i
13b FibORE 4 MONITOR 5 OMIT 5 MONITORINb O.0034 KS 11WL PC.S LEVEL IPEADS LEWL R QOt% ERROR O.00%
CORRECr PCS LEVEL. H)6R SELEUS ELT10N ERROR
),2, E-y VALVES CARE SPRm VALVES 0 0075 WKR EVENTTREE FOR MANVAU.S OPEWIN6 CORE SPRA'i vat.VE5 M01010 AND M07071
'l
Page 14 TABLE 1 Fire Event Tree CRD Makeup Sequences Sequence Description F MYC Failure of Fire Supression Successful Emergency Condenser Valve Main Condenser PCS Isolation PCS Makeup Emergency Condenser Makeup RDS/ Core Spray F MIYC Failure of Fire Supression Successful Imergency Condenser Valve Main Condenser MSIV PCS Isolation by Turbine / Condenser Valves Emergency Condenser Makeup PCS Makeup RDS/ Core Spray l
l RA0786-0150A-BQ01 1
Page 15 TABLE 2 CRD Makeup Requirements Following a Fire CRD Pump
- Mission Time Time To To Preclude Low Reactor Level Within Case Low level let 72 Hrs 1.
Primary System Isolated 2 sps PCS Leakage (Normal Leakage) 2 Emergency Condenser Loop Cooldown 234 Hrs.
O Hrs.
i 2.
Primary Systes Isolated I
10 spa PCS Leakage (Tech Spec l
1eakage) l 2 Emergency Condenser Loop Cooldown 43 Hrs.
1 Hr.
l l
l 3.
Primary System Open to Main Condenser **
10 spm PCS Leakage (Tech Spec Leakage) 2 Emergency Condenser Loop Cooldown 25 Hrs.
2} Hrs.
I l
4.
Primary System Open to Main Condenser **
l 10 spa PCS Leakage (Tech Spec j
Leakage) 1 Emergency Condenser Loop Cooldown 14 Hrs.
- 3) Hrs.
- Single CRD pump operation (25 spa) Assumed
- Steam Flow to main condenser through Air Ejectors and Bypass Warsing Line I
l RA0786-0150A-BQ01 i
l
16 r
a TABLE 3 VALUES NEEDED FOR QUANTIFICATION i
i CRD PUMP FAILURE TO RUN(FTR) 1.91E-4/ hour PRA-II-345 l
CRD PUMP FAILURE TO START (FTS) 3.00E-4/ demand 11-345 i
CRD OUT FOR MAINTENANCE (OFM) 3.17E-3/ year 11-349 CV-4090 FAILURE TO OPEN(FTO) 1.00E-3/ demand II-346 CV-4090 FAILURE TO REMAIN OPEN 1.01E-3/ hour 11-345 EDG-FTS 1.79E-2/ demand 11-345 l
i EDG-FTR 1.97E-2/ hour 11-345 i
J EDG-OFM 3.00E-3/ year 11-349 MANUAL VALVE FTO 1.00E-4/ demand II-345 DIESEL FIRE PUMP FTS 3.06E-3/ demand 11-345 DFP FTR 2.50E-5/ hour 11-345 i
DFP OFM 1.33E-4/ year 11-349 HUMAN RELIABILITY ANALYSIS CRD #1 TO EDG
.0323 FIGURE 3 i
]
MANUALLY OPENING CORE SPRAY
.0075 FIGURE 4 J
1' j
VALVES MO-7070 AND 7071 1
I, 1
l l
1 f
l l
1 i
1
4 17
-e TABLE 4 CASE NUMEER CRD PUMP PCS MAKEUP AFFECTED UNRELIABILITY UNRELIABILITY CORE DAMAGE PROBfBILITY.
01: 1 PUMP ON EDG 4.4E-3 0.157 5.3E-5 t
02 2 PUMPS ON EDG 1.3E-3 0.154 5.2E-5 (OPTION 1) 1 03: 1 PUMP ON EDG
.2.0E-3 0.155 5.2E-5 14 DAY LCO C4: 1 PUMP DN EDG 4.4E-3 0.002 1.1E-7 CORE SPRAY C5: 2 PUMP DN EDG 1.28E-4 0.153 5.2E-5 (OPTION 2)
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