ML19156A459
| ML19156A459 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 06/05/2019 |
| From: | Exelon Generation Co |
| To: | NRC/RGN-III/DRS/OLB |
| Roach G | |
| Shared Package | |
| ML17214A858 | List: |
| References | |
| Download: ML19156A459 (4) | |
Text
Dresden 2019 Initial License Exam Outline Review Comments 1
Simulator Scenario Outline Comments General Comments o NRC: In Scenarios 1 and 3, how will Critical Task RPV 5.12 be assessed with regards to power excursions greater than 5%? During an ATWS power indication is generally not stable as various actions outside of pressure control (SLC injection, lowering level, tripping RR pumps, inserting rods) all have an impact on power. In addition, why was inhibiting ADS and terminating and preventing injection from certain systems (e.g. core spray) not considered as possible Critical Tasks during scenarios including ATWS conditions?
Facility: Clarification: This critical task is not met if erratic reactor control results in a significant (> 5%) increase in reactor power when maintaining pressure within the prescribed control band was achievable. Achievable means within the control of the operating team to maintain within band using available pressure control methods.
o NRC: In Scenario 2, are Critical Tasks PC 1.1 and PC 1.2 appropriate for this scenario? D-1 only indicates a small steak leak. Will containment conditions challenge primary containment integrity if Drywell Sprays are not used? Action is only considered a Critical Task if its omission will result in direct adverse consequences or significant degradation in the mitigative capability of the plant.
Facility: During preparation and validation containment pressure exceeded 9 psig which is the EOP directed pressure to initiate drywell sprays to preclude chugging.
o NRC: Scenario 2, Critical Task RPV 2.3 suggests that not all ADS/SRV valves open for blowdown. There is no event specifically listed on the D-1 which indicates a failure of an SRV/ADS valve. I am assuming earthquake damage causes ADS/SRV to malfunction.
Facility: ERV malfunction was removed at the suggestion of the technical validators/facility representative. Removed Critical task RPV 2.3 from the D-1 for scenario 2.
o NRC: Scenario 2, Event 3 has the potential to lead to a manual scram if crew assesses multiple control rods moving simultaneously. Is there any value to moving to event to just before major event?
Facility: This was not a concern by technical reviewers/validators during development. If desired this event may be moved to later in the scenario with little impact.
o NRC: Scenario 3, Event 2, requires the ATC to raise power with RR flow from an IC of 70%. Presuming that Event 1 results in a loss of an RFP, how much room for power increase is available with only 2 functioning RFPs?
Dresden 2019 Initial License Exam Outline Review Comments 2
Facility: During development/validation, sufficient margin to operating limits was available to raise power 50 MWE.
o NRC: What are the indications for Scenario 3, Event 4? I do not believe the crew will receive an annunciator for this failure.
Facility: 902-5 F-3, ROD DRIVE HI TEMP, will alarm in Scenario 3, event 4 o NRC: The spare scenario outline was not provided with the submittal.
Facility: Dresden Station has not included the spare scenario D-1 or D-2 in previous ILE submittals. Unless administered, it is not desired that the spare scenario be made publically available.
Technical Specification Event Concerns:
o NRC: Scenario 4, Event 4 requires a Tech Spec call for a failed IRM channel. Is this a required channel or can it just be placed in bypass without entering a TS? If so, simply referring to TS is not sufficient to credit this event for an SRO TS call.
Facility: The Tech Spec call is based on a phone call received during event 4. The Tech Spec call is not directly related to the initiating IRM event. The Tech Spec could be added as a separate event on the D-1 and D-2 to eliminate confusion.
o NRC: Scenario 1, Event 2, spurious HPCI initiation Tech Spec call should include all TS affected by failed instrumentation which led to system initiation. Recent lessons learned for a similar event on the 2018 LaSalle ILE resulting in significant changes to D-2s after exam given.
Facility: Without being informed by maintenance personnel of the specific failure the SRO would be unable to determine the Tech Spec call relating to the failed instrumentation. This information is not in the D-2 because it is not desired to have this Tech Spec determined at this time.
Dresden 2019 Initial License Exam Outline Review Comments 3
JPM Outline Comments General Comments o NRC: RO Admin JPM, PERFORM CALCULATION FOR RADIOACTIVE DISCHARGE TO RIVER, was previously performed during the 2017 NRC Exam as an SRO Admin JPM. It is understood that the 2017 NRC exam and 2017 NRC retake only included SRO candidates and that the 2015 and 2016 NRC exams were used as previous 2 NRC exams for RO admin JPM selection. But, as this JPM was on the 2017 NRC exam it raises two questions. Why is this appropriate to now ask as an RO Admin JPM? Why is this not coded as previous two exams?
Facility: This JPM has been administered to both SRO and RO candidates on the same NRC exam in previous years. Either license level could be expected to perform this task. The NSO is tasked with entering the determining and entering the alarm setpoints into the SPING. This specific instance was not coded as previous two exams due to one of the critical tasks requiring a decision to be made that is different from the 2017 NRC exam.
o NRC: SRO Admin JPM, DETERMINE ACTIONS REQUIRED FOR A SECURITY THREAT, appears to require the use of SAFEGUARDS material. How will this be controlled during the review and administration process?
Facility: The body of the JPM does not contain any safeguard information. When this JPM was previously administered on an NRC exam, the concern regarding safeguards information was only on the content contained in the JPM itself.
o NRC: None of the control room systems/evolutions is coded as an engineered safety feature (EN) as required by NUREG 1021, ES-301, Page 13 and note on ES-301-2.
Facility: JPMs D, E, and H are ESF systems and have been coded as such on the ES-301-2 forms.
Dresden 2019 Initial License Exam Outline Review Comments 4
Overall Operating Exam Comments o NRC: SRO-I #2 should have Events 6, 7 and 8 counted as major events on their ES-301-5 form for Scenario 3 as the BOP for consistency with other operators and the Scenario 3 ES-D-1 form. This will change their total to 7 for major events during the scenario set.
Facility: This has been updated on the ES-301-5 for SRO-I #2.
Written Exam Outline/Audit Exam Outline o NRC: Potential conflict between RO written exam question covering K/A 295033 High Secondary Containment Radiation Levels, Generic 2.4.2 Knowledge of system set points, interlocks and automatic actions associated with EOP entry conditions and Operating Test Scenario 4, Event 7 Emergency Depressurize on 2 areas above max safe radiation levels.
Facility: The facility recognizes the potential but believes there is no conflict.
o NRC: Potential conflict between RO written exam question covering Tier 3 K/A 2.3.7, Ability to comply with radiation work permit requirements during normal or abnormal conditions and SRO Admin JPM SELECT PERSONNEL FOR RADIATION WORK.
Facility: The facility recognizes the potential but believes there is no conflict.
o NRC: Potential conflict between SRO written exam question covering Tier 3 K/A 2.4.25 Knowledge of fire protection procedures and SRO Admin JPM INITIATE A FIREWATCH.
Facility: The facility recognizes the potential but believes there is no conflict.