ML091120062
| ML091120062 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 03/31/2009 |
| From: | Dominion Nuclear Connecticut |
| To: | Caruso J Operations Branch I |
| Hansell S | |
| Shared Package | |
| ML082600232 | List: |
| References | |
| 50-336/09-301, TAC U01634, FOIA/PA-2011-0115 50-336/09-301 | |
| Download: ML091120062 (31) | |
Text
RO Question #2 The plant was operating at 100% power with all equipment in a normal alignment. Bus 24C is supplying Bus 24E. The "C" RBCCW Pump suddenly trips on fault. The Balance of Plant (BOP) operator starts the "B RBCCW Pump to supply Facility 2 and places the 'C' RBCCW Pump handswitch in Pull-To-Lock. NO other operator action is taken.
Then, a circuit failure in the Facility 2 ESAS Actuation Cabinet causes an inadvertent actuation of SIAS, CIAS, EBFAS and UV ALL plant systems and components function as designed (including those driven by the Facility 2 inadvertent actuation).
Which of the following correctly describes the condition of the RBCCW Pumps and Heat Exchanger TCVs based on the inadvertent ESAS actuation?
Q-35 (RO & I-SRO)
A The 'A' and 'B' RBCCW Pumps are running.
'A' heat exchanger TCV throttling on temperature.
'B' and 'C' heat exchanger TCVs full open.
B The 'A' and 'B' RBCCW Pumps are running.
'A' and 'B' heat exchanger TCVs throttling on temperature.
'C' heat exchanger TCVs full open.
C Only the 'A' RBCCW Pump is running
'A' heat exchanger TCV throttling on temperature.
'B' and 'C' heat exchanger TCVs full open.
D Only the 'A' RBCCW Pump is running
'A' and 'B' heat exchanger TCVs throttling on temperature.
'C' heat exchanger TCVs full open.
This is the choice designated as correct on the exam as given.
This choice is technically correct.
The following slides explain why.
Q-35 (RO & I-SRO)
The next three slides are pages from the Loss of RBCCW Abnormal Operating Procedure, AOP-2564 B RBCCW Pump SIAS/LNP Start Block Switch Explanation
Loss of RBCCW AOP-2564 Page 3, Step 1.2, Discussion Section Q-35 (RO & I-SRO)
Purpose and Function of the SIAS/LNP Block Switch
Loss of RBCCW AOP-2564 Page 15, Step 6.1 C RBCCW Pump Trip Q-35 (RO & I-SRO)
Loss of RBCCW AOP-2564 Page 16, Step 6.1g C RBCCW Pump Trip, Start the B RBCCW Pump Q-35 (RO & I-SRO)
The next slide is a page from the RBCCW System Normal Operating Procedure, OP-2330A Q-35 (RO & I-SRO)
Includes additional info on Includes additional info on the SIAS/LNP Block Switch
RBCCW System Procedure, OP-2330A, Page 11, Step 4.2, Shifting From A RBCCW Pump to B RBCCW Pump Q-35 (RO & I-SRO)
Additional info on the Additional info on the SIAS/LNP Block Switch
The B RBCCW Pump SIAS/LNP is in Block Switch, located on the pump breaker cubicle front panel.
Shown in the BLOCK position B RBCCW Pump 4160 VAC Breaker on 24E Q-35 (RO & I-SRO)
BLOCK position.
RBCCW PUMP B SIAS/LNP START MANUALLY BLOCKED annunciator on C-06/7 will alarm when the B RBCCW Pump handswitch is NOT in Pull-To-Lock and this switch is in BLOCK.
Q-35 (RO & I-SRO)
RBCCW Heat Exchangers Temperature Control Valves (TCV)
Q-35 (RO & I-SRO)
Q-35 (RO & I-SRO)
SIAS on either facility will fail 2-SW-8.1B full open
SRO Question #2 I-SRO Question #77 While performing a plant cooldown, the crew was about to place Shutdown Cooling (SDC) in service with "A" and "B" Reactor Coolant Pumps (RCPs) in service when Pressurizer Pressure Narrow Range Instrument, P-103-1, suddenly fails high.
Which of the following describes the impact of this failure and the action that the US must direct to stabilize the plant?
A The "A" Power Operated Relief Valve (PORV) will open and RCS pressure will rapidly lower.
Place the "A" LTOP switch to 'High', close PORV Block Valve, secure the "A" & "B RCPs, and Q-77/2 (I-SRO/SRO) g,
place SDC in service.
B The Facility 1 Safety Injection Tank (SIT) Outlet Valves will open causing the SITs to inject.
Override and close the SIT Outlet Valves and restore Pressurizer level to the desired setpoint.
C SDC Suction Isolation Valve, SI-652, will NOT open until the high pressure input is cleared.
Direct I&C to bypass or disconnect Pressurizer Pressure Narrow Range Instrument, P-103-1.
D The "B" Power Operated Relief Valve (PORV) will open and RCS pressure will rapidly lower.
Immediately place the associated PORV Block Valve to 'Close' and log into the LTOP Technical Specification LCO.
Correct Answer as given, which is believed to be invalid
Pressurizer Pressure Instruments 2 transmitters (PT-103/103-1) provide signals to:
Low temperature over pressure protection.
Low range (0 1600 psia) indication on C03 Q-77/2 (I-SRO/SRO)
Slide is from Reactor Coolant System L.P. RCS-00-C Low range (0-1600 psia) indication on C03.
Indication of both on C-21 panel.
SDC suction valve interlock Prevent suction valve from opening with RCS >265 psia.
Alarm if on SDC and > 280 psia.
Auto opening of SIT isolation valves at 300 psia increasing.
Q-77/2 (I-SRO/SRO)
The next slide is a page from the Shutdown Cooling System Text, SDC-00-C Explanation of How P-103 & P-103-1 Effect SI-651 & SI-652
Q-77/2 (I-SRO/SRO)
Effect of P-103 & P-103-1 High Pressure (real or failed) with SI-651 & SI-652 CLOSED Effect of P-103 & P-103-1 High Pressure (real or failed) with SI-651 & SI-652 OPEN
Q-77/2 (I-SRO/SRO)
Alarm response for P-103-1 high and with SI-651 OPEN.
Loss of Shutdown Cooling Procedure, AOP-2572, is not referenced.
SI-651 will not open until the p
failed instrument, P-103-1, is repaired or bypassed by I&C.
Q-77/2 (I-SRO/SRO)
Alarm response for P-103 high and with SI-652 OPEN.
Loss of Shutdown Cooling Procedure, AOP-2572, is not referenced.
SI-652 will not open until the p
failed instrument, P-103, is repaired or bypassed by I&C.
Next Slide
Q-77/2 (I-SRO/SRO)
Cut-Away of P-103 RCS Pressure input to SI-652 OPEN permissive, from P&ID 25203-32008, Sh. 33 SI-652 can not be opened until the failed instrument, P-103, is repaired or bypassed by I&C.
Q-77/2 (I-SRO/SRO)
Thi i th d
th The next slide is a page from the Loss of Shutdown Cooling Abnormal Operating Procedure, AOP-2572 This is the procedure the operators would normally use for guidance on the recovery of SDC as an RCS heat sink.
Q-77/2 (I-SRO/SRO)
Because there is no impact on the Shutdown Cooling System if P-103 or P-103-1 were to fail high with SI-651
& SI-652 OPEN, the Loss of Shutdown Cooling Procedure, AOP-2572, does not have guidance for this failure.
With SI-651 or SI-652 closed, SDC would not yet be in service. This scenario is addressed by the Alarm y
Response Procedure (following slide).
The question did not intend to solicit operator actions outside of written procedural guidance.
SRO Question #23 I-SRO Question #98 A Fuel Handling Accident has occurred inside Containment as evidenced by several Containment process and area radiation monitors rising or in alarm. All personnel were immediately evacuated.
In order to limit personnel exposure, per AOP-2577 (Fuel Handling Accident), the Shift Manager must ensure which of the following are performed?
A The Containment (Outage) Equipment Hatch must be closed no more than Q-98/23 (I-SRO/SRO)
A The Containment (Outage) Equipment Hatch must be closed no more than 30 minutes after the event.
B Containment Purge Valves, AC-4, 5, 6, and 7 must be closed no more than 50 minutes after the event.
C The Transfer Tube Isolation Valve, RW-280, must be closed no more than 50 minutes after the event.
D One train of CRACS must be operating in Recirculation mode no more than 30 minutes after the event.
Correct Answer as given Suggested Additional Correct Answer
Tech. Spec. Changes -
Alternate Source Term Q-98/23 (I-SRO/SRO)
The next three slides are excerpts from the Alternate Source Term presentation given in License Operator Requalification Training (LORT) that all License Upgrade candidates attended.
Cycle 07-6 Operator Training C07601
Partial implementation overview Done in Sept. - Nov. 2004 Initial changes to allow relaxation of CTMT Tech. Spec. Changes -
Alternate Source Term Q-98/23 (I-SRO/SRO) g and SFP closure during outages.
Change calculated doses due to FHA in CTMT or SFP Change times for isolating and going to recirc.
in CR Changes due to a cask drop in SFP
Full implementation phase overview Done 08/29/07 Implement Reg. Guide 1.183 as basis for source term.
Allow a consistent Design Basis for all accident dose Tech. Spec. Changes -
Alternate Source Term Q-98/23 (I-SRO/SRO)
Allow a consistent Design Basis for all accident dose assessments.
Allow more Cont. Room In-leakage Allow more CTMT by-pass leakage Allow more RWST valve backleakage (IST)
Increased Pri.-to-Sec. Leakrate limit Re-define Dose Equivalent I-131 Allow more time, (1 hr), for Cont. Rm. Isolation & recirc.
Allow more time for termination of CS (4 hrs)
Technical Specification Basis Changes Tech. Spec. Changes -
Alternate Source Term Q-98/23 (I-SRO/SRO)
The next slide is page 21 from the Unit 2 EOP Users Guide Procedure, OP-2260 Q-98/23 (I-SRO/SRO)
OP-2260 contains information that explains what changed to alter the correct choice for Question #98.
Q-98/23 (I-SRO/SRO)
The is a page from the Unit 2 EOP Users Guide Procedure, OP-2260 Change #3 was made to accommodate the change in the Alternate Source Term.
The next three slides are excerpts from the Fuel Handling Accident Abnormal Operating Procedure, AOP-2577 Q-98/23 (I-SRO/SRO)
AOP-2577 contains information used to develop the original question.
The following slides also explain what changed to alter the correct choice.
Excerpts from the Fuel Handling Accident Abnormal Operating Procedure, AOP-2577 Q-98/23 (I-SRO/SRO)
Information used to develop the original question.
Information that changed in Administrative Requirements, but has not yet been changed in AOP-2577.
Excerpts from the Fuel Handling Accident Abnormal Operating Procedure, AOP-2577 Q-98/23 (I-SRO/SRO)
Procedure use guidelines dictate that, due to the order of the steps in the procedure, the action to place CRACS in recirculation mode must be started before the action to close the must be started before the action to close the Containment Equipment Hatch (VERIFY Containment Closure established).
Additional procedural guidance given in Step 3.6, next slide.
Excerpts from the Fuel Handling Accident Abnormal Operating Procedure, AOP-2577 Q-98/23 (I-SRO/SRO)
Some Examinees felt that the order of the procedure steps implies that the actions directed before the Containment Closure step must be started within any existing time limit for the action to VERIFY Containment Closure is established (original correct answer to the question).