ML19341A315
| ML19341A315 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 01/15/1981 |
| From: | Crouse R, Rowles W TOLEDO EDISON CO. |
| To: | |
| Shared Package | |
| ML19341A312 | List: |
| References | |
| NUDOCS 8101220582 | |
| Download: ML19341A315 (12) | |
Text
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O Docket No. 50-346 License No. NPF-3 Serial No. 678 January 15, 1981 Attachment A APPLICATION FOR AMENDMENT TO FACILITY OPERATING LICENSE NO. NPF-3 FOR DAVIS-BESSE NUCLEAR POWER STATION UNIT 1 Enclosed are forty (40) copies of the requested changes to the Davis-Besse Nuclear Power Station Unit No. 1 Facility Operating License No.
NPF-3, together with the supporting Safety Evaluation and Analysis for the requested change. This requested change deals with the proposal to deautomate the valve shifts caused by Incident Level 5 of the Safety Features Actuation System.
The proposed Technical Specifications changes include pages:
3/4 1-17, 3/4 3-13, 3/4 3-48, 3/4 3-50, 3/4 5-3, 3/4 5-6, 3/4 5-7, 3/4 6-11 and B3/4-12.
By cc:/
W. C. Rowles Director, Nuclear Services For R. P. Crouse Vice President, Nuclear Sworn and subscribed before me this 15th day of January 1981.
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Notary Public n.,. -.
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f.',.. -.. T i 8101220 f TA
Docket No. 50-346-License No. NPF-3 Serial No. 678 January 15, 1981 Attachment A APPLICATION FOR AMENDMENT TO FACILITY OPERATING LICENSE NO. NPF-3 FOR DAVIS-BESSE NUCLEAR POWER STATION UNIT 1 Enclosed are forty (40) copies of the requested changes to the Davis-Besse Nuclear Power Station Unit No. 1 Facility Operating License No.
NPF-3, together with the supporting Safety Evaluation and Analysis for the requested change. This requested change deals with the proposal to deautomate the valve shif ts caused by Incident Level 5 of the Safety Features Actuation System.
The proposed Technical Specifications changes include pages:
3/4 1-17, 3/4 3-13, 3/4 3-48, 3/4 3-50, 3/4 5-3, 3/4 5-6, 3/4 5-7, 3/4 6-11 and B3/4-12.
By cc:/
W. C. Rowles Director, Nuclear Services For R. P. Crouse Vice President, Nuclear Sworn and subscribed before me this 15th day of January 1981.
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Notary Eublic
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I'; 3.
Docket No. 50-346 License No. NPF-3 Attachment A Serial No. 678 January 15, 1981 I.
Changes to Davis-Besse Nuclear Power Station Unit No. 1 Technical Specifications Appendix A, changes pages:
3/4 1/17 3/4 5-6 3/4 3-13 3/4 5-7 3/4 3-48 3/4 6-11 3/4 3-50 B 3/4 1-2 3/4 5-3 See proposed changes attached A.
Time Required to Implement This change will be implemented during the first outage af ter NRC approval for which the plant will be in Operational Mode 4 for greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
B.
Reason for Change (Facility Change Request 80-278 Rev A) these changes have been proposed during discussion with NRC to address potential problems resulting from inadvertent or premature actuation of SEAS Level 5.
C.
Safety Evaluation - attached.
ATTACHMENT A Safety Evaluation and Analysis for FCR 80-278 Rev. A Safety Evaluation At present, the suctions to the decay heat (DH) and containment spray (CS) pumps are automatically transferred from the Borated Water Storage Tank (BWFr) to the Containment Emergency Sump on a Safety Features Actuation System (SFAS) trip of incident level 5.
This occurs at a BWST level between 49.5 and 55 inches. This change proposes the above described automatic transfer of these pumps be changed to manual. Because this modification removes an automated safety feature that would now be manual, the possibility of an accident of a different type not previously in the Safety Analysis Report may be increased. This therefore, identifies a unreviewed safety question. The following analysis is provided to justify this modification.
Analysis The safety function of this transfer is to protect these pumps from cavitation for lack of proper net positive suction heads and to transfer these pump suctions to the containment emergency sump during the recircu-lation mode of operation. The SFAS incident le,yel 5 trip will be used as an interlock to prevent a premature manual transfer. The following table shows the BWST levels required by this analysis for this suction transfer to be successfully performed as a manual transfer.
Table 1 BWST Level BWST Volume Description (Inches)
(Callons)
Develop Minimum Level to Transfer Suction to Containment Emergency Sump 1.
Accident Analysis minimum level to start 36 the transfer per the original analysis 2.
Instrument string inaccuracy and drift 13.5 3.
Lowes..ala inuicated reading to sta.t 49.1 control room operator action to transfer Develop Minimum Contained Volume 1.
SFAS Incident Level 5 Interlock 96 Trip-Setpoint 2.
Interlock Trip Tolerance
+ 4.5 3.
Highest (lowest) indicated level that 100.5 (91.5) interlock trip can occur 4.
Instrument string inaccuracy and drift j-, 13.5 5.
Highest (lowest) actual level that 114 (78) 122,778 interlock trip can occur (this volume
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- BW5T Level BWST Volume Description (Inches)
(Gallons) may not be available for the decay heat or containment spray pump) 6.
Instrument String drift i
1.2 7.
Highest (lowest) allowable 101.7 (90.3) interlock trip 8.
360,000 gallons required to be added 334.3 360,000 for Emergency Core Cooling System
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(ECCS) analysis 9.
Lowest safe indicated level for ECCS 448.3 482,778 Analysis in Modes 1, 2, 3, & 4 As shown in the above table, a control room operator will manually perform this transfer when the safety grade level indicators in the control room indicate between 49.5 and 96 inches (4.125 and 8 feet) of BWST level.
This will give a control room operator about 4 minutes to make the transfer safely. Since the plant under the conditions existing at this point will be in an emergency situation for a mininum of 23 minutes, the station procedures will instruct a control room operator to be looking at the BWST level indicators to initiate the manual transfer. As observed from the above calculation table, the minimum level requirements of BWST will be met if the transfer is initiated within 4 minutes after the indicated BWST level drops to 8 feet.
A control room operator will manually perform this transfer about 23 minutes after the initial SFAS trip that started all high pressure injection, low pressure injection and containment spray pumps assuming at their maximum flow. The accident analysis requires 360,000 gallons to be added for ECCS analysis when in modes 1, 2, 3 & 4.
As shown in the above table, this condition will still be met and the attached Technical Specifications are changed accordingly.
This change to manual transfer will provide the same safety function as is performed oy the present automatic transfc: - discussed above.
Hence, no adverse environment will be created by the change and the safety function of the DH and CS pumps will not be affected. This analysis is considered justifiable to support this proposed modification.
i
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ATTACHMENT B AP 3005.56,2 1
BWST LOLO LVL, XFER TO EMER SUMP 1.
STMPTOM 1.1 This alarm is generated when any one of the four SEAS BWST level bistables trips.
1,2 Setpoint: 8 feet water 1.3 Source Designation: LSL 1525A, LSL 1525B, LSL 1525C, and/or LSL 1525D
' 2.
IMMEDIATE OPERATOR ACTION 2.1 Verify that the BWST level is at 8 feet per LI 1525 A, B, C, and D.
2.2 Verify a LOCA condition exists.
2.3 Transfer pump suction to the emergency sump by blocking SFAS incident level 2 for DH9A and DH9B and then opening DH9A and DH9B using HISDH9A and HISDH9B. Verify that the.BWST outlet valves DH7A and DH7B start to close as DH9A and DH9B start to open. Verify the transfer is complete by checking the indicating lights on DH7A and B and DH9A and B and by checking that low pressure injection flow has not sub-stantially changed.
3.
SUPPLEMENTARY ACTIONS 3.1 Refer to EP 1202.06, Loss of Reactor Coolant, Reactor Coolant Pressure
SP 1104.04.15 31 DH 831 (DH 830) when DH Pump 1-1 (1-2) line flow is higher..Then balance the flow to 1500 gpm per line by adjusting the flow control. valves DH14A and DH14B.
If no air is available to DH14A and DH14B, the DH injec-tion valve DHlB (DHlA) can be throttled under emergency conditions. This motor operated valve only moves while control switch is held.
9.2.3 Deleted
- 10. RECIRCULATION FROM THE CONTAINMENT VESSEL EMERGENCY SUMP Following a LOCA, the BWST level will decrease until at the 8 feet level the
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operator must manually transfer the suction of the DH and CS Pumps to the emer-The operator will open the emergency sump outlet valves DH9A and gency sump.
DH9B and close the BWST outlet valves DH7A and B.
This operation must be com-pleted before the level falls below 5 feet.
No operator signoff is required for Section 10.
10.1 Prerequisites 10.1.1 Low Pressure Injection in progress.
10.1.2 Borated Water Storage Tank water level has reached the low level transfer setpoint (8 feet) as read on LI1525A, B, C, or D,
i 10.1.3 The annunciator "BWST LOLO LVL, XFER TO EMER SUMP" may or may not have been received.
10.2 Procedure 4
10.2.1 Block SEAS incident level 2 on DH9A and DH9B.
10.2.2 Open DH9A and DH9B using HISDH9A and HISDH9B.
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10.2.3 Verify that DH7A and DH7B start to close as DH9A and DH9B start to open.
10.2.4 Verify that the transfer is complete by checking the indicating lights on DH9A and B and DH7A and B and by checking that the Low Pressure Injection flow was not significantly changed.
l 10.2.5 Continue low pressure injection as needed.
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33 SP 1104.04.15 NOTE: The preceding three steps establish the
" piggyback" mode of operation.
If this operation is being formed to provide RCS makeup at high pressure, no further action is required until makeup is no longer needed at which time the pumps may be stopped and DH 63 and DH 64 closed.
If this operation is the result of an RCS leak and the BWST level is approaching
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8 feet, continue with the remaining stans.
j 15 11.2.4 Close the high pressure injection pump minimum recirculation valves to the BWST.
This is to minimize the contamination of the BWST and maintain off site radiation levels as low as possible.
15 NOTE:
If, DH 64 (DH 63) and HP 32 (HP 31) are both open, computer alarm Q488 (Q489) will occur.
Close HP 32 (KP 31).,
15 CAUTION:
If the high pressure injection flowrate drops to j$35 GPM per pump due to an increase in RCS pressure, stop the high pressure injection pumps 1-1 and 1-2 so as not to damage them.
11.2.5
- SEE' ATTACHED SHEET FOR STEP 11.2.5*
A 7
11.2.6 When Reactor Coolant Pressure is low enough for 15 l the Decay Heat Pumps to discharge directly to t he Reactor Cont sat System at a flow of 2000 gpm, begin Decay Heat System recirculation cf the Containment Vessel Emergency Sump as follows:
15 11.2.6.1 Stop the High Pressure Injec-tion Pumps 1-1 and 1-2 if their flow is not needed.
11.2.6.2 Shut the Decay Heat Pump discharge valves to the High Pressure Injection Pump Suction Dh 63 and DH 64.
Section 11 Completed
_Date
11.2.5 When BWST level reaches 8 feet, transfer pump suction to the emergency sump by blocking SFAS incident level 2 for DH9A and DH9B and then opening DH9A and DH98 using HISDH9A and HISDH9B. Verify that the BWST outlet valves DH7A and DH7B start to close as DH9A and DH98 start to
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open. Verify the transfer is complete by checking the indicating lights on DH7A and B and DH9A and B and by checking that low pressure injection flow has not substantially changed.
4 m
EP 1202.0614 6
E 3
METERS, the hot leg termperature -
E$0E If either the RCS TSAT or the incore thermocouple temperatures x - := o. w indic'a tions,
EE*gt indicate super-heated conditions for the existing refer to AB 1203.06, Inadequate Core Cooling
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' pressure, An increase in the source or intermediate Guidelines.
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- range nuclear instrumentation may also indicate an, n af 0 E 5dxE" inadequate core cooling situation.
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"S0"S 2.4.1.3
'If both main and auxiliary feedwater is lost, refer to o u.,< uu E##E@
43 1203.05, Complete Loss of Main and Auxiliary Feed-water, to aid in restoring auxiliary feedwater ip the U.E*. " "
E m.$ D %
event both OTSGs are dry.
"E5Yf g *$$w 2.4.1.5 Determine the availability of reactor coolant pumps
- o. D
- d (RCPs).
If any RCPs are running, go to 2.4.2.
If all u EI ei RCPs are off, go to 2.4.3.
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- El ggg,,
2.4.2 Actions with at itast one RCP r6nning no<oo Ue@"#
Maintain one RCP running per loop (stop other pumps).
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2.4.2.1 Oow3*
Continued operation of at least one RCP is desirable.
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The only conditions requiring RCPs be stopped would be E$$$3 eUw5*
if RCS pressure falls below 1650 psig such that SFAS I E $.o M incident level 2 is actuated or if the RCP vibration E5 as measured by the Bentley-Nevada equipment. exceeds 30 mills. Note that the X2 (times-two) switch on the i
- O' I <.o J
jE))=5 Bentley-Nevada equipment must be used for the expanded range.
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I 2.4.2.2 Allow RCS pressure to stabilize.
If RCS pressure cen-g[j$g gog tinues to decrease past secondary side pressure, the M*
3e leak is large and section 3 should. be consulted.
M G c oo 30.8%eE 2.4.2.3 Establish and maintain OTSG cooling by adjusting steas c e " 3.E E pressure via the turbine bypass valves and/or atmos-m7*"5 phetic wat valves.
Cccidown at 100 F per hour to y
ach t.s t' : n RCS or~; cure of 250 psig.
Track the cool-
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g-gg down on Figures 2 at.d 3.
Isolate core flood tanks M
3ggacg when 50 F subcooling (using RCS T METERS) is SAT g uoggg attained and RC pressure is less than 700 psig.
yg5g7g
. 3,lopk.SFAs level :3.wher" leas than 600 psis.
ueyg
=g 2.4.2.4
.Go into LPI ' cooling desNibed in 2.5.'1 ' ~
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,{gg]e, u vs a m.c 3Eugag 2.4.3 Actions with no RCPs running cc0AE*
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> A m 2.4.3.1 Verify that the OTSG 1evel is maintained at 96" on the u g c4 ugy startup range by auxiliary feedwater.
5 a.g c g,
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4 EEEE*3 NOTE:
If desired, the OTSG IcVel may be raised as high mmaop as 95% on the operate range to improve RCS coeling 4
but the transition must be slow enough to prevent excessive changes in RCS pressure and temperature.
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EP 1202.06.13 16 2.7 Discussion For the purposes of this procedure, a medium sized leak is one for which the BPI pump capacity is sufficient to maintain pressurizer level or RCS If the HPI pumps cannot keep up with the leak, then RC pres
- pressure.
sure will fall until the LPI system can provide additional makeup; this is defined as a large leak and is discussed in the next section.
Depending on the size of the leak, the RCS pressure will slowly or quickly fall to the 1600 psig pressure setpoint of the SFAS for level 1 add 2 Note that for small breaks with a complete loss of feedwater, actuation.
RCS pressure may not fall low enougt.- to actuate SFAS levels 1 and 2.
Manual actuation of SFAS could be accomplished by actuating each component in level 1 or 2 or by actuating levels 1, 2, 3, and 4,
Manual except C.S. pumps, by means of the manual actuation pushbutton.
actuation will result in natural circulation of the RCS and an SFRCS u0 actuation. Operator action shall be taken to re-establish the seal o
nu0*
injection and CCW to the MU Pumps to allow continuous operation of the Manual actuation should NOT be used unless the SFAS setpoints are
.EEEd RCPs.
Once HPI is initiated and reached and the actuation does not occur.
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level is restored to enable pressure control, a cooldown can be. started.
The cooldown should proceed normally with the exception that one of the e%.Ef
$$"5 ECCS pumps must remain in operation in the injection mode to makeup the M S' 3
- water lost out of the leak. HPI can be shutdown within the limits of 9eO" item 6 of 2.6.1.
5 i3 "
d If possible the depressurization/cooldown will be complete before the g
BWST low level is reached and the "piggybacking" of the HPI and Decay 5Ao Heat Pumps will not be necessary. If the depressurization/cooldown cannot
'E d E 5
- a. E e N be coupleted in time, the pressurizer level may be maintained by aligning
!l3.
the Decay Heat Pumps to take a suction from the emergency sump and discharge U !"$
to the suction of the HPI pumps.
DI.*i 80333 A flow path from the RCS hot leg to the DH System must be established u
@d me 2 within seven days to prevent boron concentration buildup as described in E $ 0 " 8.
Section 3.4.8.
If this flow path cannot be established, an alternate path through the auxiliary spray line must be used.
.E O " E.E "n0*"
If an operator blocks an SFAS signal and changes the status of the actua-3 % 3 *3 ted equipment, he is responsible for assuring proper equipment operation e08eE and re-initiation if requitad until the SFAS is reset. For guidance on g
OcGTU resetting the SFAS after a real or erroneous trip, see Section 4.0.
U e d c:
E.E For additional details on possible consequences of a medium sized leak, o
- a. " E. $
see The Evaluation of Transient Behavior and Small Reactor Coolant
!$3TO System Breaks in the 177 Fuel Assembly Plant - Section 5 (B&W).
"$sEm T8$"u Notes on Step 2.4.3.5 0 U.E O I When this step is reached, auxiliary feedvater has established a 96" level u
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N6"m3 in the OTSGs and no RCS flow exists (forced or natural). Depending on the Uu$e8 size of the break, the RCS may repressurize enough to reach the code safety valves setpoint.
If the electromatic relief is available, the RCS pressure
"$"38 s
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may be reduced manually.
If not, the RCS pressure will be relieved by the
[*"Euo break and the safeties if the pressure goes that high. At some pressure, the energy escaping from the break (and the electromatic or safeties if used) 9 t
EP 1202.0&l4 9
IS e
1.4 Supplementary Actions u
u a
ec E$'5.3 Implement Site Emergency Procedure, EI.1300,04, UTE8U' EOa E
CAUTION: DO NOT BLOCK AND OVERRIDE ANY SAFETY EQUIPMENT EXCEPT AS SPECI-OmEdM FIED IN SECTION 2.4.3.
U$ tie
,, 5 w g 5.3 x g g becomes unbaJanecd, throttle the HPI valves and split the flow a t g 3 g, between the injection lines. Do NOT throttle the line with the high flow below the flow rate shown on Figure 4.0.
Assure "S0y 3 j " >,$,S proper HPI operation per Section 5.0 of SP 1104.07, "HPI O)."a
. Operating Procedure".
E o. E U.E bet"
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- 2 u83&E 3 0
- E.t E 3$
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3.4.2 Verify the LPI pumps are injecting into the RCS when RCS pres-sure decreases to approximately 200 psig by reading FI DH2B and 5 gag a
FI LH2A on C5716.
No throttling of the LPI valves is required
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if both LPI pumps are in operation. since mechanical stops are ggggg installed on the cooler outlet valves. Assure proper LPI opera-Etmg4 tion per Section 9 of SP 1104.04, "LPI Operating Procedure".
I E $ -o $
gA 3.4.3 If a DH Pump has failed and a break does not exist outside of
""A g'$ < ]
containmente close the suction on the disabled pump, open DH831 A
3 a. " $ "
or DH830, and balance flous using DH14A and DH14B if available
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"u5AA or DHlA and DHlB if DH14A and DH14B cannot be throttled.
c' O 5 E ~E such as reactor coolant pumps, E eo e
- 3.4.4 Stop any non essential equipment ~
- EDEN makeup pumps, etc.
Although the RCPs will probably trip on a d
EI5 loss of CCW an'd seial injection, DO NOT STOP MORE THAN ONE RCP S
Soc PER LOOP UNLESS A MINIMUM OF 3000 gpm TOTAL DECAY HEAT FLOW HAS 0Uc" 5
BEEN ESTABLISHED.
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= m " 3 'E E k
3.4.5 If LPI flow is greater than 1000 goe per cump for 20 minutes, the m]
25 operator may stop the HP1 pumps. Unless the HP1 pumps are peggy-backed, the HPI pumps must be stopped before the suction is manual-
,gg,g pg ly transferred to the emergency sump on low BWST level (8 feet).
3ggagg If LPI flow is less than 1000 gpm per pump, open HPI to LPI cross-g waegg ggy yg connect-.as per_Section. ll of the DH and LPI Operating Procedure, E
m34gcg SP 1104.04 before the suction is transferred to the emergency sump.
E"$5e$
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3.4.7 See Section 4.0 of this procedure for guidance before overriding.
c e d 'E 3 C any other safety equipment.
0.E N #5E
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tion, assure CS 1530 and CS 1531 throttle when recirculating
% { O S.$ C
$u f rom the emergency sump.
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D:ckst Ns. 50-346 l
Licinas N3. NPF-?
Serial No. 678 ATTACEMENT C January 15, 1981 Description of Operation During normal plant operation the BWST Outlet Valve is open and the corresponding Containment Emergency Sump Valve is closed. An inter-lock exists between the two valves that would prevent the sump valve from being opened until the BWST Outlet Valve is fully closed.
On a Level 2 SFAS actuation, the valves will remain in their normal position. At this point, the blocking of Level 2 SFAS signals will still not allow the Containment Emergency Sump Valve from being opened until the BWST Outlet Valve is closed. When Level 5 of SFAS is ac-tuated neither valve will move. At this point, if the Level 2 SFAS signal is blocked, the Level 5 signal will block the interlock allowing the operator to manually open the Containment Emergency Sump Valve.
When the Containment Emergency Sump Valve begins to open, another inter-lock between the two valves will start closing the BWST Outlet Valve.
The transfer to the sump will be totally manual and no automatic opera-tion will be involved.
- - -.