ML16138A092
| ML16138A092 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 05/04/2016 |
| From: | Janak G South Texas |
| To: | Kelly Clayton NRC Region 4 |
| References | |
| NOC-AE-16003381 | |
| Download: ML16138A092 (21) | |
Text
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Nuclear Operating Cornpany Sou/II &as Proft:ctEklric ~tins Slatton P.a Bar 28J' ~.* ~ 7N:J May;10,,2016 NOC-AE-16003381
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10 CFR55 Kelly Clayton (Addressee Only)
Chief Examiner, Region IV U.S. Nuclear Regulatory Commission 1600 E. Lamar Blvd.
Arlington, TX 76011-4511 South Texas Project Units 1and2 Docket Nos. STN 50-49a, STN 50-499 Written Examination Results The written portion of the NRC License exam was administered on May 4, 2016 atthe South Texas Project. In accordance with NUREG 1021, Operator Licensing Examination Standards for Power Reactors, STP Nuclear Operating Company (STPNOC) Is submitting the following examination materials In electronic form on the enclosed CD-ROM.
- Master examinations and answer keys annotated to Indicate changes made
- Applicant questions/clarifications
- Examination performance analysis
- Applicant comments following the written examination
- Seating chart In addition, the following documentation is attached:
- Graded written examinations with cover sheet and clean copy of answer sheet The completed ES-201-3, Examination Security Agreement will be forwarded to you as soon as possible.
STP Nuclear Operating Company requests that NRC 'consider the attachments to this letter as Exempt from Public Disclosure. None of these exam .materials sho'uld go to the Pub.lie Document Room (ADAMS) for two years.
- There are no commitments in this letter.
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STI 34318026
NOC-AE-16003381 Page 2 of 3 If you have any questions, please contact Stan Mason at (361) 972-4356 or at (361) 972-7586.
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Gregory W. Janak Manager, Operations Training
Enclosure:
CD-Rom with Post-Exam Information Attachments: t. ES-401-3, Written Exam Grad1ng Quality Checklist
- 2. Graded Written Exams
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(paper copy without attachments) (electronic copy without attachments)
Laura Hurley Morgan. Lewis & Beckius LLP '
Operator Licensing Assistant, Region IV U.S. Nuclear Regulatory Commission Steve Frantz, Esquire i 1600 East Lamar Boulevard Arlington, TX 76011-4511 U.S. Nuclear ReguJatorv Commission Lisa M. Regner i~
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Regional Administrator, Region IV '
U.S. Nuclear Regulatory Commission NRG South Texas LP 1600 East Lamar Boulevard Arlington, TX 76011-451 1 Chris O'Hara Jim von Suskil I
Skip Zahn I Lisa M. Regner j
j Senior Project Manager CPS Energy j 1
U.S. Nuclear Regulatory Commission Kevin Pollo 1 One White Flint North (08H04) Cris Eugster ~
11555 Rockville Pike L. D. Blaylock 1 Rockvllle.* MD 20852 ']
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'I NRC Resident Inspector U. S. Nuclear Regulatory Commission P. 0. Box 289, Mall Code: MN116 Crain Caton & James, P.C.
Peter Nemeth I Wadsworth, TX 77483 Attention: Document Control Desk City of Austin Elaina Ball I
U.S. Nuclear Regulatory Commission John Wester Washington, DC 2055~0001 Texas Dept. of State Health Servlces Helen Watkins Robert Free RM without attachments
STPEGS LOT 20.1 Written Exam Student Questions and Clarifications 5/4/2016 The following are clarifications given to questions on the LOT 20.1 Written Exam:
RO Question #10 (EB #594)
Unit 1 was stable at 100 % power when a piping failure in the Generator Hydrogen Supply Header caused Main Generator hydrogen pressure to lower.
After the leak was isolated, the following conditions exist:
- Generator hydrogen pressure - 45 psig
- Generator output- 1300 MWe
- Generator reactive load - 300 MVARs OUT Based on these conditions, and referring to Figure 7.1 (attached), which of the following represents the HIGHEST ALLOWABLE amount the generator load should be reduced to?
A. 1225 MWe and 240 MVARs OUT.
B. 1225 MWe and 100 MVARs OUT.
C. 1175 MWe and 340 MVARs OUT.
A. 1175 MWe and 200 MVARs OUT.
Correct Answer D Student Question (1)-Doesn't the graph for the Main Generator Capability Curve have bolded lines for the indicated graph numbers?
Proctor Response - The graph given for the Main Generator Capability Curve is the same graph used in the Control Rooms.
No other clarification given. Use question as written.
STPEGS LOT 20.1 Written Exam Student Questions and Clarifications 5/4/2016 RO Question #12 (EB #2580)
The Unit is at 100% power with the following conditions:
- Rod Control is in automatic.
Subsequently:
- An inadvertent boration occurs that lowers Tave by 3°P.
Control rods will step in at a maximum of (1) steps per minute and will stop stepping in when the T error is (2)
A. (1) 6 (2) 1°P B. (1) 6 (2) 0°P
- c. (1) 33 (2) 1°P D. (1) 33 (2) 0°P Correct Answer A Student Question (1)- Where the stem states 'Control rods will step in ... ' and' ...
will stop stepping in ... ' shouldn't it state that 'Control rods will step out ..." and
' ... wt*11 stop steppmg
. out . . . '?.
Proctor Response - Had students change 'in' to 'out' where noted.
NOTE: As indicated in the stem of the question, an inadvertent boration would cause control rods to step out. This change does not cue students to the correct answer on this question or any other exam question on the exam and is considered a typographical error. A change to the exam key was also made.
STPEGS LOT 20.1 Written Exam Student Questions and Clarifications 5/4/2016 SRO Question tl47 (EB #2440)
A Reactor Trip and Safety Injection have occurred due to a Small Break LOCA with the following conditions:
- All Reactor Coolant Pumps (RCPs) are running.
- All LHSI Pumps are secured and in AUTO.
Subsequently:
- HHSI Pump B trips on overcurrent.
- RCS Pressure lowers to 390 psig and stabilizes.
Per OPOP05-EO-E010, Loss of Reactor or Secondary Coolant, RCPs should be ill and LHSI Pumps should be ill A. (1) running (2) secured in AUTO B. (1) secured (2) secured in AUTO
- c. (1) running (2) running A. (1) secured (2) running Correct Answer D Student Question (1) - Have the operator actions ofOPOP05-EO-E010, Loss of Reactor or Secondary Coolant, been taken?
Proctor Response-The stem of the question states 'Per OPOP05-EO-E010, Loss of Reactor or Secondary Coolant' the status 'should be.'
No Clarification given. Use question as written.
STPEGS LOT 20.1 Written Exam Student Questions and Clarifications 5/4/2016 SRO Question #57 (EB #2475)
During a Large Break LOCA, if the Safety Injection Accumulators failed to inject, what would be the effect on water being used to cool the core?
During the recirculation phase, if the Safety Injection Accumulators failed to inject, the ECCS water recirculated through the core would have a ill boron concentration and a ill pH.
A. (1) higher (2) lower B. (1) lower (2) lower
- c. (1) higher (2) higher D. (1) lower (2) higher Correct Answer D Student Question (1) - Is the first and second parts of the stem of the question referring to the same event?
Proctor Response - Yes. The first and second parts of the stem of the question are referring to the same event.
No other clarification given. Use question as written.
STPEGS LOT 20.1 Written Exam Student Questions and Clarifications 5/4/2016 The following are questions asked by students but no clarifications were given:
RO Question #95 (EB #2458)
The Unit is at 100% power with the following conditions:
- Train A and Train B RCFCs are running.
- Train A CCW Pump is running.
Subsequently:
- 13.8KV Standby BUS G loses power.
The Unit Supervisor will direct actions of...
A. Addendum 1, Sequencer Loading Verification of OPOP04-AE-00001, First Response to Loss of Any or All 13.8 KV or 4.16 KV Bus, and align 'B' Train CCW to the RCFCs.
B. Addendum 3, Equipment Placed in Pull-To-Lock ofOPOP04-AE-00001, First Response to Loss of Any or All 13.8 KV or 4.16 KV Bus, and place 'B' Train equipment in PTL.
C. OPOP02-HC-0002, Normal Containment Purge, Section 5 to start the Normal Containment Purge System.
D. OPOP02-HC-0001, Containment HVAC, Section 5 to re-start 'B' train RCFCs.
Correct Answer A Student Question 0)- Did the ESF DGs start and load the ESF 4.16KV Buses?
Proctor Response - No Clarification given. Use question as written.
LOT 20.1 NRC EXAM ANALYSIS - 5/4/2016 Bank# RO# SRO# ANSWER A B c D Total Missed 96 1 D 486 2 D 1101 3 c 2508 4 B 2489 5 D 2493 6 D 16 7 c 18 8 B 27 9 A 594 10 D 1 1 715 11 B 1 1 2580 12 A 816 13 B 2584 14 B 2582 15 B 1 1 1053 16 c 1189 17 A 1355 18 B 2597 19 B 1579 20 B 1584 21 D l 1 2 1689 22 A 2583 23 B 1755 24 D 1833 25 c 2502 26 c 2579 27 c I 2 3 2600 28 D 2599 29 c 2096 30 c 2097 31 B 1 1 2 2368 32 D 2442 33 B.
2446 34 A 3 3 2466 35 A 2 2 2469 36 D 3 3 2488 37 A 2601 38 B 2252 39 c 2305 40 D 1 1 2321 41 A 2323 42 D 1 1 2494 43 B 3 3
LOT 20.1 NRC EXAM ANALYSIS - 5/4/2016 Bank# RO# SRO# ANSWER A B c D Total Missed 2332 44 B 1 I 2 2333 45 c 2439 46 A 2440 47 D 2441 48 A 1 1 2444 49 D 2588 50 c 2467 51 c I I 2 2468 52 A 1 1 2470 53 A 2501 54 A 1 1 2473 55 c 1 1 2503 56 c 1 1 2475 57 D I I 2 1116 58 B 2477 59 c 2478 60 A 1 1 2479 61 A 1 1 2480 62 D 2481 63 D 2 2 2482 64 B 2589 65 A 2484 66 B 1 1 2486 67 c 2487 68 A 2490 69 c 2586 70 c 2116 71 D 2197 72 A 62 73 B 2581 74 A 1 1 2471 75 D 2461 76 A 2577 77 B 1 )
661 78 D 2505 79 A 968 80 A 1 ]
2598 81 B 1 l 2590 82 B 2445 83 B 2447 84 c 2448 85 c 2463 86 D 2450 87 c I 1
LOT 20.1 NRC EXAM ANALYSIS - 5/4/2016 Bank# RO# SRO# ANSWER A B c D Total Missed 2353 88 c 2452 . 89 A 2453 90 c I l 2454 91 A 2455 92 D 2449 93 -* c l I 2457 94 A 2458 95 A 2459 96 B 2460 97 B 2293 98 D 2464 99 c 2491 100 D RO #21 - 1 candidate chose distracter "A"; 1 candidate chose distracter "C"; (correct answer is "D").
Question is based on CCW alarm setpoints and alarm response. Distracters chosen indicate a lack of knowledge of CCW Alarm Response Procedures. Training is given in the lesson plan for CCW. LOT 201.12.
No changes to the exam are warranted.
LOT 20.1 NRC EXAM ANALYSIS - 5/4/2016 RO #27 -1 candidate chose distracter "A"; 2 candidates chose distracter "B"; (correct answer is "C").
This question was written based on the entry conditions for OPOP04-AE-0005, Offsite Power System Degraded Voltage. Simply stated the correct answer is C.
All 3 applicants missed this question in addition to 3 out of 4 licensed operators during validation of the question. The one licensed operator that got this question right was an SRO on shift because he had to enter the procedure the week before.
In reviewing the question we looked at validation comments and the STP Owner Communication Plan. Validation comments indicated that only SROs perform this procedure and when performing the procedure they get a peer check from other SROs. The STP Owner Communication Plan states that the electrical transmission distribution representatives will contact the Shift Manager (SRO) to provide information on the status of the transmission grid, such as current electrical voltage. Nowhere in the STP Owner Communication Plan does the RO get involved with these communications.
Based on this review it was determined that the entry conditions for OPOP04-AE-0005, Offsite Power System Degraded Voltage, are more complex than other AOP entry conditions. In addition, an SRO is responsible for the actions of this procedure and the question cannot be answered solely on fundamental knowledge of the entry conditions for OPOP04-AE-0005, Offsite Power System Degraded Voltage.
This question validated as an SRO question and the question is not linked to RO requirements.
Even though the question is technically correct, STP recommends that the NRC review this question for an exception to the NUREG 1021 SRO versus RO question requirements.
RO #31-1 candidate chose distracter "A"; 1 candidate ch,ose distracter "D"; (correct answer is "B").
Question is based on the interface between CCW and RCPs. Distracters chosen indicate a lack of knowledge of when and what is actually cooled by CCW in regards to the RCPs. Training is given in the lesson plan for RCPs and CCW. LOT 201.05 and 201.12.
No changes to the exam are warranted.
RO #34 - all 3 candidates chose distracter "B"; (correct answer is "A").
Question is based on knowledge of RO responsibilities during the Emergency Plan. The designated ENS Communicator is responsible for activating the Emergency Response Notification System. (ENRS) The responsibility was recently given to the ENS Communicator.
No changes to the exam are warranted, however, a CR Action has been created to evaluate if a change to LOT Training is needed to address this issue.
In addition, feedback from the candidates revealed that if the question stem had mentioned activating ERO pagers then they believe they would have picked the correct answer. The question stem will be evaluated to address this feedback.
LOT 20.1 NRC EXAM ANALYSIS - 5/4/2016 RO #35-2 candidates chose distracter "B"; (correct answer is "A").
Question is based on the actions and their basis in response to a SGTR. The distracter chosen indicates a lack of knowledge of the primary reason the RCS and ruptured SG pressures are equalized. Distracter 'B' is the secondary reason for this action and not the primary. Training is given in the lesson plan for OPOP05-EO-E030. LOT504.15 No changes to the exam are warranted.
RO #36 - all 3 candidates chose distracter "C"; (correct answer is "D").
Question was written in regards to the basis for OPOP04-Z0-0001, Control Room Evacuation.
During review with the students it was noted that in the basis on page four for tripping the Reactor/Main Turbine it states; 'The operator trips the reactor. The RNO directs the operator to open the reactor trip breakers. Remote reactor trip capability is not available at the ASP. Thus, the reactor should be tripped prior to Control Room evacuation.' Therefore 'C' is an acceptable answer because tripping the Reactor/Main Turbine is a control function not available at the ASP. See LOT 20.1 NRC Exam Applicant Comments.
Recommend changing answer key to allow both "C" & "D" to be the correct answers.
RO #43 - all 3 candidates chose distracter "D"; (correct answer is "B").
Question is based the types of ESF DG electrical trips and whether or not they are NORMAL only or NORMAL and EMERGENCY trips. Applicants choosing distracter "D" indicate a lack of knowledge on NORMAL versus EMERGENCY trips. Training is given during LOT 201.39 forESFDGs.
No changes to the exam are warranted.
RO #44-1 candidate chose distracter "C"; 1 candidate chose distracter "D"; (correct answer is "B).
Question is based on flow path for FHB Exhaust HVAC. Distractors chosen indicate a lack of knowledge of where the Radiation Monitors are in the flow stream. Training is given in the lesson plan for FHB HVAC. LOT 202.38.
No changes to the exam are warranted.
RO #51-1 candidate chose distracter "A"; 1 candidate chose distracter "D"; (correct answer is "C").
Question is based on knowledge of Differential Rod Worth and the effects of a dropped control rod on the RCS parameters. Distractors chosen indicate a lack of knowledge of how a dropped control rod effects RCS parameters given its position in the core. Training is given in the lesson plan for Reactor Theory Control Rod Worth. LOT 101.22.
No changes to the exam are warranted.
LOT 20.1 NRC EXAM ANALYSIS - 5/4/2016 RO #57 -1 candidate chose distracter "B"; 1 candidate chose distracter "C"; (correct answer is "D").
Question is based on knowledge of the effects on cooling water to the RCS during a LOCA if the SI Accumulators failed to inject. Distractors chosen indicate a lack of knowledge of how boron concentration and pH of recirc water would be affected. Training is given in the lesson plan for ECCS .. LOT 201.10.
No changes to the exam are warranted.
RO #63 -2 candidates chose distracter "B"; (correct answer is "D").
This question was written based on the system lesson plan for the Rod Control system. If there was no operator action Control Rod Bank 'D' will step in only as N42 failed high to try to lower what the system believes is a high reactor power. When there is no change between Reactor power and turbine power then the control rods will stop. Therefore 'D' is a correct answer.
During the exam review, the students that missed this question stated that they chose Answer 'B' based on the immediate action steps ofOPOP04-NI-0001, Nuclear Instrument Malfunction.
In reviewing this question and with the given failure of Power Range Channel N42 failing high, the operator would be required to perform the immediate action of0POP04-NI-0001, Nuclear Instrument Malfunction, which is to 'ENSURE "ROD BANK SELECTOR SW" in MAN.' This action will stop control rod movement and could happen before there is no mismatch between turbine and reactor power due to it being an immediate action. Therefore, with the question as written, 'B' is also a correct answer.
Based on the newly discovered technical information that supports a change in the answer key and looking at Answers 'B' and 'D' independently, they are both correct answers for the given condition. See LOT 20.1 NRC Exam Applicant Comments.
SRO #77- SRO candidate chose distracter "A"; (correct answer is "B").
Question is based on knowledge of procedure usage for a steam line rupture. Distractor chosen indicates a lack of knowledge for when a transition would be made to OPOP05-EO-EC21, Uncontrolled Depressurization of all Steam Generators. Training is given in the lesson plan for LOT 504.13 for faulted SGs and Lesson Plans for procedures OPOPOS-EO-EOIO, Loss of Reactor or Secondary Coolant, and OPOP05-EO-E020, Faulted Steam Generator Isolation.
No changes to the exam are warranted.
SRO #80- SRO candidate chose distracter "D"; (correct answer is "A").
Question is based on knowledge ofEOP implementation hierarchy. Distractor chosen indicates a lack of knowledge ofCSF procedure entry. Training is given in the lesson plan for LOT 504.04, Introduction to EOPs.
No changes to the exam are warranted.
LOT 20.1 NRC EXAM ANALYSIS - 5/4/2016 SRO #81 - SRO candidate chose distracter "A"; (correct answer is "B").
Question is based on knowledge of TS requirements for Intermediate Range Nuclear Instruments. Distractor chosen indicates a lack of knowledge of Nuclear Instrument TSs.
Training is given in the lesson plan for Technical Specifications. LOT 503.01.
No changes to the exam are warranted.
SRO #87 - SRO candidate chose distracter "D"; (correct answer is "C").
Question is based on knowledge of actions in OPOP05-EO-FRS 1, Response to Nuclear Power Generation ATWS. Distractor chosen indicates a lack of knowledge of when and how the procedure is exited. Training is given in the lesson plan for OPOP05-EO-FRS1, Response to Nuclear Power Generation ATWS. LOT 504.28.
No changes to the exam are warranted.
LOT 20.1 NRC EXAM ANALYSIS - 5/4/2016 SRO #90- SRO candidate chose distracter "D"; (correct answer is "C").
This question was based on actions taken in OPOP04-CR-0001, Loss of Condenser Vacuum. For most of the life of the Units at STP, operators have been trained through OPOP04-CR-0001, Loss of Condenser Vacuum, to reduce Main Turbine load to help restore condenser vacuum for a condenser vacuum leak. This would make 'C' the correct answer.
During the exam review the SRO candidate stated that he answered the question by choosing Answer 'D' because it is the correct flow path of the procedure.
In reviewing this question, it was discovered that a condition report, CR #16-4923, was written because during a Crew Performance Evaluation a crew performed a fast load reduction in the simulator for a similar condition as stated in this question when in actuality the procedure, OPOP04-CR-0001, Loss of Condenser Vacuum, did not call for a fast load reduction. In 2014 the procedure revised following main turbine repairs. During a loss of vacuum due to air in leakage, down powering the unit is not desirable because it brings the unit toward the restricted zone for turbine operation.
A fast load reduction is only required if the unit is in the restricted zone per Addendum 2 of the procedure. In the question given with the unit at 100% power the unit would be outside the restricted zone. Therefore 'C' cannot be the correct answer.
With the trend given in the stem of the question for condenser vacuum at 23.7" HG and slowly lowering, the procedure puts the unit in a loop at step 10 until condenser vacuum reaches 21" HG. When condenser vacuum reaches 21" HG, then at step 9 RNO the operator is to 'ENSURE Reactor is tripped, ENSURE Main Turbine is tripped and GO TO OPOP05-EO-EOOO, Reactor Trip or Safety Injection.' Therefore the correct answer is 'D'.
During further review it was noted that CR #16-4923 states the following: Conduct the performance analysis to determine appropriate course to address the following observation: During a recent simulator scenario and after limited polling of operators there is a mindset that during a loss of condenser vacuum events it is desirable to reduce turbine loading to mitigate the event. This is contrary to the direction provided in OPOP04-CR-0001.
A Performance Analysis was performed and a gap was identified and training will be required. The specifics of the training will be identified by a Training Analysis which is currently in progress.
Based on the newly discovered technical information that supports a change in the answer key, answer 'D' is the correct answer. See LOT 20.1 NRC Exam Applicant Comments.
LOT 20.1 NRC EXAM ANALYSIS - 5/4/2016 SRO #93 - SRO candidate chose distracter "D"; (correct answer is "C").
Question is based on knowledge of Emergency Plan entry level requirements. Distractor chosen indicates a lack of knowledge flow charts used for Emergency Plan implementation. Training is given in the lesson plan for Emergency Plan Classification. LOT 803 .14.
No changes to the exam are warranted.
POST-EXAM QUESTION CHALLENGES BY STP STP LOT 20.1 NRC WRITTEN EXAM 5/4/2016 Question #36 - EB 2469: (missed by all three applicants - all 3 chose 'C')
During a control room evacuation due to a fire, in accordance with OPOP04-ZO-OOOI, Control Room Evacuation, why is the Reactor/Main Turbine tripped before leaving the control room?
Because of...
A. a loss of Main Feedwater.
B. a loss of EHC control to the Main Turbine.
C. the lack of control functions available at the Auxiliary Shutdown Panel.
D. the possibility of spurious operation or unavailability of supporting equipment.
Keyed answer: D COMMENT: This question was written using the basis of0POP04-ZO-OOOI, Control Room Evacuation, Addendum 23. Page I of the basis section discusses the overall procedure and its strategy. It states in the final paragraph on page I; 'Evacuation of the Control Room due to a fire requires actions that are unique to the existing conditions due to the possibility of spurious operation or unavailability of specific components. When the evacuation is required due to a condition that does not involve fire, such as toxic gas or high radiation levels, there is no reason to assume that any safety related equipment may spuriously operate or become unavailable.' Therefore
'D' is a correct answer.
During the exam review, all three applicants stated that the basis supported 'C' being a correct answer.
In reviewing the question, the basis on page 4 for tripping the Reactor/Main Turbine states; 'The operator trips the reactor. The RNO directs the operator to open the reactor trip breakers. Remote reactor trip capability is not available at the ASP. Thus, the reactor should be tripped prior to Control Room evacuation.' Therefore 'C' is also a correct answer because tripping the Reactor/Main Turbine is a control function not available at the ASP.
Based on the newly discovered technical information that supports a change in the answer key, both 'C' and 'D' are correct for tripping the Reactor/Main Turbine before leaving the Control Room for a fire in the control room. STP recommends accepting both 'C' and 'D' as correct answers.
RECOMMENDATION: Accept both 'C' and 'D' as correct.
(ES-403, D.1.b, 3rd bullet)
NRC RESOLUTION:
POST-EXAM QUESTION CHALLENGES BY STP STP LOT 20.1 NRC WRITTEN EXAM 5/4/2016 Question #63 - EB 2481 (missed by SROI and ROI - both chose 'B')
The Unit is at 75% power with the following conditions:
- Control Bank 'D' is at 230 steps.
- Rod Control is in Auto.
Subsequently:
- Power Range Channel N42 fails high.
What effect will this failure have on the Rod Control system?
Control Bank 'D' will step . . .
A. OUT until stopped by C- I I (248 steps).
B. IN until the RO places Rod Control in Manual.
C. OUT until Tave and Tref are matched.
D. IN until no change is occuring between turbine and reactor power.
Keyed answer: D COMMENT: This question was written based on the system lesson plan for the Rod Control system. If there was no operator action Control Rod Bank 'D' will step in only as N42 failed high to try to lower what the system believes is a high reactor power. When there is no change between Reactor power and turbine power then the control rods will stop. Therefore 'D' is a correct answer.
During the exam review, the SROI and ROI both stated that they chose Answer 'B' based on the immediate action steps of0POP04-NI-OOOI, Nuclear Instrument Malfunction.
In reviewing this question and with the given failure of Power Range Channel N42 failing high, the operator would be required to perform the immediate action of0POP04-NI-OOOI, Nuclear Instrument Malfunction, which is to 'ENSURE "ROD BANK SELECTOR SW in MAN.' This action will stop control rod movement and could happen before there is no mismatch between turbine and reactor power due to it being an immediate action. Therefore, with the question as written, 'B' is also a correct answer.
Based on the newly discovered technical information that supports a change in the answer key and looking at Answers 'B' and 'D' independently, they are both correct answers for the given condition. STP recommends accepting both 'B' and 'D' as correct answers.
RECOMMENDATION: Accept 'B' or 'D' as correct.
(ES-403, D. I .b, 3rd bullet)
NRC RESOLUTION:
POST-EXAM QUESTION CHALLENGES BY STP STP LOT 20.1 NRC WRITTEN EXAM 5/4/2016 Question #90 EB- 2453: (missed by SROl - chose 'D,)
The Unit is at 100% power with the following conditions:*
- Main Condenser vacuum is 23. r HG and slowly lowering.
The low Main Condenser vacuum would be caused by a _ __..ill_l___ and the Unit Supervisor would direct ill (1) (2)
A. Condensate Pump trip and failure of a fast load reduction per OPOP04-CD-the standby pump to start 0001, Loss of Condensate Flow B. Condensate Pump trip and failure of the immediate actions ofOPOP05-EO-the standby pump to start EOOO, Reactor Trip or Safety Injection
- c. Condenser Air Removal Pump trip and a fast load reduction per OPOP04-CR-failure of the standby pumps to start 0001, Loss of Condenser Vacuum D. Condenser Air Removal Pump trip and the immediate actions of OPOP05-EO-failure of the standby pumps to start EOOO, Reactor Trip or Safety Injection Keyed answer: C See comments on next page.
POST-EXAM QUESTION CHALLENGES BY STP STP LOT 20.1 NRC WRITTEN EXAM 5/4/2016 COMMENT: This question was based on actions taken in OPOP04-CR-0001, Loss of Condenser Vacuum. For most of the life of the Units at STP, operators have been trained through OPOP04-CR-0001, Loss of Condenser Vacuum, to reduce Main Turbine load to help restore condenser vacuum for a condenser vacuum leak. This would make 'C' the correct answer.
During the exam review SROl stated that he answered the question by choosing Answer 'D' because it is the correct flow path of the procedure.
In reviewing this question, it was discovered that a condition report, CR #16-4923, was written because during a Crew Performance Evaluation a crew performed a fast load reduction in the simulator for a similar condition as stated in this question when in actuality the procedure, OPOP04-CR-0001, Loss of Condenser Vacuum, did not call for a fast load reduction. In 2014 the procedure revised following main turbine repairs. During a loss of vacuum due to air in leakage, down powering the unit is not desirable because it brings the unit toward the restricted zone for turbine operation.
A fast load reduction is only required if the unit is in the restricted zone per Addendum 2 of the procedure. In the question given with the unit at 100% power the unit would be outside the restricted zone. Therefore 'C' cannot be the correct answer.
With the trend given in the stem of the question for condenser vacuum at 23.7" HG and slowly lowering, the procedure puts the unit in a loop at step 10 until condenser vacuum reaches 21" HG. When condenser vacuum reaches 21" HG, then at step 9 RNO the operator is to 'ENSURE Reactor is tripped, ENSURE Main Turbine is tripped and GO TO OPOPOS-EO-EOOO, Reactor Trip or Safety Injection.' Therefore the correct answer is 'D'.
During further review it was noted that CR #16-4923 states the following: Conduct the performance analysis to determine appropriate course to address the following observation: During a recent simulator scenario and after limited polling of operators there is a mindset that during a loss of condenser vacuum events it is desirable to reduce turbine loading to mitigate the event. This is contrary to the direction provided in OPOP04-CR-OOO 1.
A Performance Analysis was performed and a gap was identified and training will be required. The specifics of the training will be identified by a Training Analysis which is currently in progress.
Based on the newly discovered technical information that supports a change in the answer key, answer 'D' is the correct answer. STP recommends the keyed answer be changed to 'D'.
RECOMMENDATION: Change keyed answer to 'D'.
(ES-403, D.1.b, 3rd bullet)
NRC RESOLUTION: