ML072970053

Brunswick July-August Exam 50-325, 324/2007301 Final Simulator Scenarios (Scenario 2 of 4) (Section 4 of 4)

ML072970053
Person / Time
Site:	Brunswick
Issue date:	01/31/2007
From:	- No Known Affiliation
To:	Office of Nuclear Reactor Regulation
References
50-324/07-301, 50-325/07-301 50-324/07-301, 50-325/07-301
Download: ML072970053 (12)

See also: IR 05000325/2007301

Text

• SCRAM CARD*ENSURE SCRAM VALVES ARE OPEN BY MANUAL!-.

OR ARlTRIP"\\*

REACTOR PRESSURE BETWEEN 800 AND 1000 PSIG*CONTROL REACTOR VESSEL LEVEL BETWEEN+.170 AN-D+200 INCHES*INSERT NUCLEAR INSTRUMENTATION

."*PLACE RECIRC PUMP SPEED CONTROLLERS

TO 10%*ENSURE HEATER DRAIN PUMPS ARE TRIPPED*ENSURE TURBINE OIL SYSTEM OPERATING*PLACE SULCV IN SERVICE

(((\

• STEP RC/Q-15"",I PERFORM"ALTERNATE

CONTROL ROO INSERTION" (EOP*01*LEP*02)STEP BASES: I RC/Q-15 Concurrent

execution of this step with the remainder of this procedure optimizes efforts to achieve reactor shutdown.EOP-01-LEP-02 (Alternate

Control Rod Insertion)

addresses alternate methods of control rod insertion.

Reactor shutdown on control rod insertion alone is preferable

to injecting boron for the following reasons: a.Boron injection contaminates

the primary system, requiring extensive cleanup and subsequent

inspection

before continued plant operation is possible.*b.If a leak occurs below the elevation of the reactor water level being maintained, boron injection may not be successful

in shutting down the reactor.c.A reactor shutdown on boron is not necessarily

a stable condition;

if boron is subsequently

diluted or displaced by a leak or an operational

error, the reactor could return to criticality.

Several alternate methods for inserting control rods are presented in EOP-01-LEP-02.

See the Step Discussions

for EOP-01-LEP-02

for a detailed discussion

of these methods.*1001-37.5 Rev.8 Page 87 of 90 I

• • STEPS RCtO-OS through RCtO-10 (continued)

The Boron Injection Initiation

Temperature

is defined to be the greater of: a.The Suppression

Pool temperature

at which initiation

of a reactor scram is required by Technical Specifications, or b.The highest Suppression

Pool temperature

at which initiation

of boron injection using SLC will result in injection of the Hot Shutdown Boron Weight of boron before Suppression

Pool temperature

exceeds the Heat Capacity Temperature

Limit.Criterion b is a function of reactor power;a higher reactor power level causes higher integrated

heat energy to be rejected to the Suppression

Pool thus requiring a lower Suppression

Pool temperature

for initiation

of boron injection if the Heat Capacity Temperature

Limit is not to be exceeded before reactor shut down is achieved.At Brunswick, a single value is used for Boron Injection Initiation

Temperature

(110°F)for procedure simplification

.*1 001-37.5 Rev.8 Page 82 of 90 I

STEPS RC/O-OB through RC/O-10 YES NO RClQ*10 STEP BASES: If reactor power is above 2%, the operator is directed to inject boron.This is a conservative

action because with power above 2%, Suppression

Pool temperature

will steadily increase towards 110°F.This also allows sufficient

time for the Hot Shutdown Boron Weight of boron to be injected.The extra time may be needed since thealternatesystems

used for boron injection require significantly

more time to inject boron should the SLC System fail.The SLC system is initiated to shut down the reactor.As long as the core remains submerged (the preferred method of core cooling), fuel integrity and reactor vessel integrity are not directly challenged

even under

scram conditions.

A scram failure coupled with an MSIV isolation;

however, results in rapid heatup of the Suppression

Pool due to the steam discharged

from the reactor vesselviaSRVs.The challenge to containment

thus becomes the limiting factor which defines the requirement

for boron injection.

If Suppression

Pool temperature

and reactor pressure cannot be maintained

below the Heat Capacity Temperature

Limit, rapid depressurization

of the reactor vessel will be required.To avoid depressurizing

the reactor vessel with the reactor at power, it is desirable to shut down the reactor prior to reaching the Heat Capacity Temperature

Limit, thus minimizing

the quantity of heat rejected to the Suppression

Pool.The Boron Injection Initiation

Temperature

is defined so as to achieve this when practicable.

1001-37.5 Rev.8 Page 81 of 90 I

.*STEP RC/L-29 CAN REACTOR YES WATER LEVEL BE RESTORED ANO MAINTAINED

ABOVE LL*4

NO*STEP BASES: When reactor water level cannot be restored and maintained

above the LL-4, emergency depressurization

is required for the purpose of maximizing

injection flow from high head pumps and to permit injection from low-head pumps.Prior to emergency depressurization, high reactor pressure may have precluded injection from low-head pumps.Depressurizing

the reactor is preferred over restoring reactor water level through the use of systems which inject inside the shroud because: a.A large reactor power excursion may result from in-shroud injection.

b.Rapiddepressurization,by

itself, will reduce reactor power due to a substantial

increase in voids.c.Following the depressurization, reactor power will stabilize at a lower level.*1001-37.5 Rev.8 Page 29 of 90 I

• STEP RC/L-29 (continued)

Emergency depressurization

is not required until reactor water level cannot be restored and maintained

above LL-4 because: a.Adequate core cooling exists so long as reactor water level remains above LL-4, or even momentarily

drops below LL-4.b.The time during which reactor water level decreases to LL-4 can best be used to line up and start pumps in additional

injection systems listed in Table 1, which might not yet have been placed in service.**1001-37.5 Rev.8 Page 30 of 90 I

• STEPS RC/P-40 and RC/P-41 I (TERMINATE AND PREVENT\INJECTION TO THE REACTOR VESSEL FROM THE FOLLOWING SYSTEMS UNLESS THE SYSTEM IS BEING USED TO INJECT BORON:*CONDENSATEJFEEDWATER

• HPCI*RHR*CORE SPRAY*ALTERNATE COOLANT\INJECTION SYSTEMS J I RCIP-40 WHEN INJECTION TO THE REACTOR VESSEL FROM THE SPECIFIED SYSTEMS HAS BEEN TERMINATED

AND PREVENTED, RAPIDLY DEPRESSURIZE

THE REACTOR IRRESPECTIVE

OF RESULTING COOLDOWN RATE AS FOLLOWS I RClP-41

• STEP BASES:Injectioninto

the reactor vessel is terminated

and prevented before Emergency Depressurization

proceeds in order to prevent uncontrolled

injection of large amount of cold water as reactor pressure decreases below the shutoff head of operating system pumps.Injection from boron injection systems and CRD is not terminated

because operation of these systems may be needed to establish and maintain reactor shutdown.Further, the injection flow rates from these systems are small compared to those of the other systems used to control reactor water level.Injection from RCIC is not terminated

because the injection flow rate from this system is small, continued operation of the turbine aids in depressuring

the reactor vessel, and operation during reactor depressurization

is not expected to result in significant

injection flow rate variations.

Only when the listed systems have been terminated

and prevented is emergency depressurization

allowed.*1001-37.5 Rev.8 Page 66 of 90 I

(

• Section 3-The purpose of this section is to insert control rods by repeated manual scram, overriding

RPS if required.NOTE Manpower Required: Special Equipment:

1 Control Operator 4 jumpers (15,16,17, and 18)co: co: 1.2.Unit 1 Only: ENSURE the REACTOR MODE SWITCH, C71-S1, is in*SHUTDOWN.*

Unit 2 Only: IF steam flow is less than3X 10 6 lb/hr, THEN ENSURE the REACTOR MODE SWITCH, C72-S1,i"S

in RSHUTDOWNR.

NOTE Steps 3 and 4 may be performed concurrently.

3.IF an automatic scram signal is present AND power is available to the RPS bus, THEN INSTALL the following jumpers to bypass the reactor scram:**co: co: co: co: a.b.c.d.Jumper 15 in Panel H12-P609, Terminal Board DD, from the right side of Fuse C71A(C72A)-F14A

to Terminal 4 of Relay C71A(C72A)-K12E.

Jumper 16 in Panel H12-P609, Terminal Board BB, from the left side of Fuse C71A(C72A)-F14C

to Terminal 4 of Relay C71A(C72A)-K12G.Jumper 17 in Panel H12-P611, Terminal Board DD, from the right side of Fuse C71A(C72A)-F14B

to Terminal 4 of Relay C71A(C72A)-K12F.Jumper 18 in Panel H12-P611, Terminal Board BB, from the left side of Fuse C71A(C72A)-F14D

to Terminal 4 of Relay C71A(C72A)-K12H.I OEOP-01-LEP-02

Rev.25 Page 13 of 281

Section 3-Continued*4.INHIBIT ARI by performing

the following steps;co: co: co: a.b.c.PLACE ARI AUTO/MANUAL

INITIATION

switch, Cll(C12)-CS-5560, to"INOP".PLACE ARI RESET switch (spring return), Cll(C12)-CS-5562, to"RESET" and

for a minimum of five (5)seconds, THEN RELEASE.VERIFY the red"TRIP" light located above ARI INITIATION, Cll(C12)-CS-556l

is off.co: 5.ENSURE the DISCH VOL VENT&DRAIN TEST switch is in"ISOLATE".

6.VERIFY the following valves are closed: RESET RPS.d.DISCH VOL DRAIN VLV Cll(C12)-CV-FOll

• co: co: co: co: co: 7.a.b.c.DISCH VOL VENT VLV Cll(C12)-V139

DISCH VOL VENT VLV Cll(C12)-CV-F010

DISCH VOL DRAIN VLV Cll(C12)-V140

co: co: 8.9.IF RPS CANNOT be reset, THEN RETURN to Step C.6 on Page 2.PLACE the DISCH VOL VENT&DRAIN TEST switch to"NORMAL".10.VERIFY the following valves are open:*co: co:

co: co: a.b.c.d.DISCH VOL VENT VLV Cll(C12)-V139

DISCH VOL VENT VLV Cll(C12)-CV-F010

DISCH VOL DRAIN VLV Cll(C12)-V140

DISCH VOL DRAIN VLV Cll(C12)-CV-FOll

I OEOP-01-LEP-02

Rev.25 Page 14 of 281

• Section 3-Continued co: 11.WHEN the scram discharge volume has drained for approximately

2 minutes OR SDV HI-HI LEVEL RPS TRIP annunciator (A-OS 1-6)clears, THEN CONTINUE in this procedure.

NOTE" IF venting control rod over piston area in accordance

with Section 6, THEN the AO should be notified so venting can be secured, prior to inserting a manual SCRAM.CO: 12.Manually SCRAM the reactor.13.IF control rods moved inward, THEN PERFORM the following:

14.IF control rods DID NOT move inward, THEN RETURN to Step C.6 on Page2.**CO: CO: CO: a.b.IF all control rods are inserted to or beyond position DO, THEN RETURN to Step C.6 on Page 2.IF all control rods are NOT inserted to or beyond Position DO, THEN RETURN to Step S on Page 14.I OEOP-01-LEP-02

Rev.25 Page 15 of 281