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Category:Letter
MONTHYEARML23180A1512023-06-29029 June 2023 LLC, Request for Exemption to the Reporting Requirements of 10 CFR 50.46(a)(3) ML21102A3072021-04-15015 April 2021 OEDO-21-00155 - Lessons-Learned from the Design Certification Review of the NuScale Power, LLC, Small Modular Reactor ML21050A4312021-02-19019 February 2021 LLC - Lessons-Learned from the Design Certification Review of the NuScale Power, LLC Small Modular Reactor ML20247J5642020-09-11011 September 2020 Standard Design Approval for the NuScale Power Plant Based on the NuScale 600 Standard Plant Design Certification Application ML20231A8042020-08-28028 August 2020 Final Safety Evaluation Report for the NuScale Standard Plant Design ML20224A4602020-08-25025 August 2020 OEDO-20-00292-Response to the Advisory Committee on Reactor Safeguards Letter on NuScale Power, LLC, Report on the Safety Aspects of the NuScale Small Modular Reactor ML20231A5982020-08-25025 August 2020 OEDO-20-00285_NuScale Area of Focus - Boron Redistribution ML20210M8902020-07-29029 July 2020 Area of Focus - Boron Redistribution ML20195A5872020-07-13013 July 2020 LLC - Submittal of Draft Operator Licensing and Examination Standard for NuScale Small Modular Reactors ML20195C7662020-07-13013 July 2020 LLC Request for Standard Design Approval Based on the NuScale Standard Plant Design Certification Application ML20192A3262020-07-10010 July 2020 LLC, Submittal of Environmental Report: Revision Status ML20198M3932020-07-0202 July 2020 LLC Submittal of Revised Packing Slip for Submittal of the NuScale Standard Plant Design Certification Application, Revision 4.1, Dated June 19, 2020 ML20174A3472020-07-0101 July 2020 OEDO-20-00220 - Area of Focus - Probabilistic Risk Assessment and Emergency Core Cooling System Valve Performance ML20184A2872020-07-0101 July 2020 LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topic - Boron Redistribution and General Design Criterion 33, PM-0720-70785, Revision 0 ML20181A4322020-06-22022 June 2020 Final SER for NuScale TR-0516-49416 NON-Loss-of-Coolant Analysis Model, Rev 3 (Letter) ML20181A2702020-06-22022 June 2020 Final SER for NuScale TR-0516-49422 Loss-of-Coolant Analysis Model, Rev 2 (Letter) ML20198M3922020-06-19019 June 2020 LLC - Submittal of the NuScale Standard Plant Design Certification Application, Revision 4.1 ML20171A7312020-06-19019 June 2020 LLC, Submittal of Riser Flow Hole Methodology and Associated Changes to Final Safety Analysis Report Incorporating Its Use ML20157A2232020-06-0303 June 2020 Letter to NuScale Requesting -A for TR-0716-50350 ML20150C5172020-05-29029 May 2020 LLC Submittal of Presentation Materials Entitled NRC Public Meeting Presentation: Boron Redistribution and Associated Design and DCA Changes, PM-0620-70336, Revision 0 ML20150E1772020-05-29029 May 2020 LLC - Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topic - Extended Dhrs Operation and RCS Boron Redistribution (Closed Session), PM-0620-70243, Revision 0 ML20150C8812020-05-29029 May 2020 LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topic - Boron Redistribution and Associated Design and DCA Changes, PM-0620-70244, Revision 0 ML20149M1192020-05-28028 May 2020 LLC Summary of Impacts to Erai 8930 Response and Discussion on the Exemption from General Design Criterion 33 ML20141L8082020-05-20020 May 2020 LLC Submittal of Containment Response Analysis Methodology Technical Report, TR-0516-49084, Revision 3 ML20141N0122020-05-20020 May 2020 LLC Submittal of Changes to Final Safety Analysis Report, Section 6.2, Containment Systems, Section 6.3, Emergency Core Cooling System, and Technical Report TR-0516-49084, Containment Response Analysis Methodology Technical Report ML20141M7642020-05-20020 May 2020 LLC Submittal of Nuclear Steam Supply System Advanced Sensor Technical Report, TR-0316-22048, Revision 3 ML20141L7872020-05-20020 May 2020 LLC, Submittal of Second Updates to Standard Plant Design Certification Application, Revision 4 ML20141L8162020-05-20020 May 2020 LLC, Submittal of Long-Term Cooling Methodology, TR-0916-51299, Revision 3 ML20141M1142020-05-20020 May 2020 LLC Submittal of NuScale Instrument Setpoint Methodology Technical Report, TR-0616-49121, Revision 3 ML20141L8042020-05-20020 May 2020 LLC Submittal of Technical Specifications Regulatory Conformance and Development, TR-1116-52011, Revision 4 ML20128J3162020-05-18018 May 2020 OEDO-20-00167 - Response to the ACRS Letter on Combustible Gas Monitoring ML20133K0882020-05-12012 May 2020 LLC, Submittal of Presentation Materials Entitled Public Meeting Presentation: Topic - Emergency Core Cooling System (ECCS) Boron Distribution (Closed Session), PM-0420-69512, Revision 0 ML20133J9142020-05-11011 May 2020 LLC Submittal of Presentation Materials Entitled Public Meeting Presentation: Topic - Emergency Core Cooling System (ECCS) Boron Distribution, PM-0420-69511, Revision 0 ML20112F4552020-05-0101 May 2020 LLC, Design Certification Application Phases 5 and 6 Review Status ML20107F8492020-05-0101 May 2020 OEDO-2000140 - NuScale Area of Focus - Helical Tube Steam Generator Design ML20104A0792020-04-27027 April 2020 OEDO-20-00115 - Safety Evaluation Report for Topical Report TR-0516-49416, Revision 2, Non-Loss-of-Coolant Accident Analysis Methodology ML20099H0802020-04-0808 April 2020 LLC - Submittal of Presentation Materials Entitled NRC Public Meeting: Revisions to Nuscale'S EPZ Sizing Methodology Topical Report, PM-0420-69598, Revision 0 ML20098G2372020-04-0707 April 2020 Nuscale Power, LLC Submittal of Remaining Closure Items for the Emergency Core Cooling System Valve Failure Mode Effects Analysis Audit Items ML20097F1922020-04-0606 April 2020 Nuscale Power, LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: Nuscale Topic - Hydrogen/Oxygen Monitoring, PM-0420-69518, Revision 0 ML20094H6742020-04-0303 April 2020 LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation NuScale Topic-Probabilistic Risk Assessment with a Focus on Emergency Core Cooling System Analysis PM-0420-69559, Revision 0 ML20092L8992020-04-0101 April 2020 LLC - Submittal of Updates to Standard Plant Design Certification Application, Revision 4 ML20072M6682020-03-30030 March 2020 Response to NuScale Letter Dated February 24, 2020, on Planned SDA Application Content ML20072H3332020-03-0909 March 2020 LLC - Submittal of Presentation Materials Entitled Public Meeting Presentation: Topic - Emergency Core Cooling System (ECCS) Boron Distribution, PM-0320-69218, Revision 0 ML20057D9002020-03-0606 March 2020 Submittal of Errata to Final SE for NuScale Power, LLC TR-1010-859-NP-A, Quality Assurance Program Description for the NuScale Power Plant ML20062F7262020-03-0505 March 2020 Request for Withholding Information from Public Disclosure for Nuscale Power, LLC Letter Public ML20069A1572020-03-0404 March 2020 LLC - Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topical Report-Rod Ejection Accident Methodology, PM-0320-69146, Revision 0 ML20069A1772020-03-0404 March 2020 LLC - Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topical Report-Non-Loss-of-Coolant Accident, PM-0320-69141, Revision 0 ML20069A9632020-03-0404 March 2020 LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topical Report, Loss-of-Coolant Accident Evaluation Model, PM-0320-69138, Revision 0 ML20066G2802020-03-0303 March 2020 LLC, Submittal of Presentation Materials Entitled ACRS Subcommittee Presentation: NuScale Topic - Hydrogen Monitoring, PM-0220-69071, Revision 0 ML20066G2882020-02-28028 February 2020 LLC Submittal of Presentation Materials Titled ACRS Full Committee Presentation: NuScale - Steam Generator Design (Closed Session), PM-0220-69053, Revision 0 2023-06-29
[Table view] Category:Response to Request for Additional Information (RAI)
MONTHYEARRAIO-0420-69855, LLC, Submittal of Corrected Response to NRC Request for Additional Information No. 284 (Erai No. 9225) on the NuScale Design Certification2020-04-30030 April 2020 LLC, Submittal of Corrected Response to NRC Request for Additional Information No. 284 (Erai No. 9225) on the NuScale Design Certification ML19332A1202019-11-27027 November 2019 LLC Supplemental Response to NRC Request for Additional Information No. 484 (Erai No. 8930) on the NuScale Design Certification Application ML19304B4712019-10-31031 October 2019 LLC Supplemental Response to NRC Request for Additional Information No. 466 (Erai No. 9482) on the NuScale Design Certification Application ML19296D8052019-10-23023 October 2019 LLC Response to NRC Request for Additional Information No. 526 (Erai No. 9719) on the NuScale Design Certification Application ML19283E5302019-10-10010 October 2019 LLC Supplemental Response to NRC Request for Additional Information No. 522 (Erai No. 9681) on the NuScale Design Certification Application ML19260G7352019-10-0707 October 2019 Summary of Public Meeting with NuScale to Discuss Response to RAI 9681 ML19266A5872019-09-23023 September 2019 LLC Supplemental Response to NRC Request for Additional Information No. 518 (Erai No. 9659) on the NuScale Design Certification Application ML19262G9742019-09-19019 September 2019 LLC - Submittal of Changes to Final Safety Analysis Report, Tier 1, Section 3.11, Reactor Building and Section 3.13, Control Building, and Tier 2, Section 3.8.4, Design of Category I Structure and Section 14.3, Certified ... ML19262G5762019-09-19019 September 2019 LLC - Submittal of Changes to Final Safety Analysis Report, Section 14.2, Initial Plant Test Program, Table 14.2-2, Pool Cleanup Systems Test #2, and Table 14.2-50, Module Assembly Equipment Test #50 ML19259B8102019-09-16016 September 2019 LLC Supplemental Response to NRC Request for Additional Information No. 205 (Erai No. 9044) on the NuScale Design Certification Application ML19259A0922019-09-16016 September 2019 LLC Response to NRC Request for Additional Information No. 525 (Erai No. 9705) on the NuScale Design Certification Application ML19238A3722019-08-26026 August 2019 LLC Supplemental Response to NRC Request for Additional Information No. 197 (Erai No. 9051) on the NuScale Design Certification Application ML19238A3662019-08-23023 August 2019 LLC - Response to NRC Request for Additional Information No. 523 (Erai No. 9682) on the NuScale Design Certification Application ML19215A0032019-08-0202 August 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 202 (Erai No. 8911) on the NuScale Design Certification Application ML19215A0062019-08-0202 August 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 441 (Erai No. 9485) on the NuScale Design Certification Application ML19212A7622019-07-31031 July 2019 LLC Response to NRC Request for Additional Information No. 523 (Erai No. 9682) on the NuScale Design Certification Application ML19212A3752019-07-31031 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 483 (Erai No. 9516) on the NuScale Design Certification Application ML19212A7992019-07-31031 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 427 (Erai No. 9408) on the NuScale Design Certification Application ML19212A6892019-07-31031 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 205 (Erai No. 9044) on the NuScale Design Certification Application ML19210D1592019-07-29029 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 401 (Erai No. 9447) on the NuScale Design Certification Application ML19210D7342019-07-29029 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 520 (Erai No. 9642) on the NuScale Design Certification Application ML19210E1462019-07-29029 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 197 (Erai No. 9051) on the NuScale Design Certification Application ML19207B3812019-07-26026 July 2019 LLC - Response to NRC Request for Additional Information No. 427 (Erai No. 9408) on the NuScale Design Certification Application ML19207A5342019-07-26026 July 2019 LLC - Response to NRC Request for Additional Information No. 523 (Erai No. 9682) on the NuScale Design Certification Application ML19207B8522019-07-25025 July 2019 LLC Response to NRC Request for Additional Information No. 194 (Erai No. 8884) on the NuScale Design Certification Application ML19203A3152019-07-22022 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 325 (Erai No. 9268) on the NuScale Design Certification Application ML19203A3212019-07-22022 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 333 (Erai No. 9282) on the NuScale Design Certification Application ML19203A3092019-07-22022 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 54 (Erai No. 8837) on the NuScale Design Certification Application ML19203A3422019-07-22022 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 154 (Erai No. 8938) on the NuScale Design Certification Application ML19200A2482019-07-19019 July 2019 LLC Response to NRC Request for Additional Information No. 522 (Erai No. 9681) on the NuScale Design Certification Application ML19200A2082019-07-19019 July 2019 LLC - Response to NRC Request for Additional Information No. 524 (Erai No. 9691) on the NuScale Design Certification Application ML19199A1172019-07-18018 July 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 484 (Erai No. 8930) on the NuScale Design Certification Application ML19198A3252019-07-17017 July 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 249 (Erai No. 9135) on the NuScale Design Certification Application ML19196A3682019-07-15015 July 2019 LLC Response to NRC Request for Additional Information No. 516 (Erai No. 9647) on the NuScale Design Certification Application ML19191A2202019-07-10010 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 197 (Erai No. 9051) on the NuScale Design Certification Application ML19184A6152019-07-0303 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 386 (Erai No. 9316) on the NuScale Design Certification Application ML19176A5802019-06-25025 June 2019 LLC Supplemental Response to NRC Request for Additional Information No. 232 (Erai No. 9113) on the NuScale Design Certification Application ML19170A3702019-06-19019 June 2019 LLC Supplemental Response to NRC Request for Additional Information No. 232 (Erai No. 9113) on the NuScale Design Certification Application ML19168A2442019-06-17017 June 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 325 (Erai No. 9268) on the NuScale Design Certification Application ML19164A1452019-06-13013 June 2019 LLC - Submittal of Containment Response Analysis Methodology Technical Report, TR-0516 -49 08 4, Revision 1 ML19157A3262019-06-0606 June 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 232 (Erai No. 9113) on the NuScale Design Certification Application ML19154A6222019-06-0303 June 2019 LLC Supplemental Response to NRC Request for Additional Information No. 202 (Erai No. 8911) on the NuScale Design Certification Application ML19154A6052019-06-0303 June 2019 LLC Response to NRC Request for Additional Information No. 514 (Erai No. 9645) on the NuScale Design Certification Application ML19151A8372019-05-31031 May 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 377 (Erai No. 9380) on the NuScale Design Certification Application ML19140A4592019-05-20020 May 2019 LLC Supplemental Response to NRC Request for Additional Information No. 401 (Erai No. 9447) on the NuScale Design Certification Application ML19137A2902019-05-17017 May 2019 LLC Supplemental Response to NRC Request for Additional Information No. 156 (Erai No. 9031) on the NuScale Design Certification Application ML19137A2872019-05-15015 May 2019 LLC Response to NRC Request for Additional Information No. 519 (Erai No. 9656) on the NuScale Design Certification Application ML19126A2942019-05-0606 May 2019 LLC Supplemental Response to NRC Request for Additional Information No. 26 (Erai No. 8840) on the NuScale Design Certification Application ML19122A5092019-05-0202 May 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 494 (Erai No. 9548)on the Design Certification Application ML19121A6002019-05-0101 May 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 202 (Erai No. 8911) on Design Certification Application 2020-04-30
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Text
RAIO-0319-65005 March 28, 2019 Docket No.52-048 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738
SUBJECT:
NuScale Power, LLC Supplemental Response to NRC Request for Additional Information No. 463 (eRAI No. 9486) on the NuScale Design Certification Application
REFERENCES:
- 1. U.S. Nuclear Regulatory Commission, "Request for Additional Information No. 463 (eRAI No. 9486)," dated May 03, 2018
- 2. NuScale Power, LLC Response to NRC "Request for Additional Information No. 463 (eRAI No.9486)," dated June 28, 2018 The purpose of this letter is to provide the NuScale Power, LLC (NuScale) supplemental response to the referenced NRC Request for Additional Information (RAI).
The Enclosure to this letter contains NuScale's supplemental response to the following RAI Question from NRC eRAI No. 9486:
20.01-17 This letter and the enclosed response make no new regulatory commitments and no revisions to any existing regulatory commitments.
If you have any questions on this response, please contact Carrie Fosaaen at 541-452-7126 or at cfosaaen@nuscalepower.com.
Sincerely, Zackary W. Rad Director, Regulatory Affairs NuScale Power, LLC Distribution: Gregory Cranston, NRC, OWFN-8H12 Omid Tabatabai, NRC, OWFN-8H12 Samuel Lee, NRC, OWFN-8H12 : NuScale Supplemental Response to NRC Request for Additional Information eRAI No. 9486 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvalis, Oregon 97330, Office: 541.360.0500, Fax: 541.207.3928 www.nuscalepower.com
RAIO-0319-65005 :
NuScale Supplemental Response to NRC Request for Additional Information eRAI No. 9486 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvalis, Oregon 97330, Office: 541.360.0500, Fax: 541.207.3928 www.nuscalepower.com
Response to Request for Additional Information Docket No.52-048 eRAI No.: 9486 Date of RAI Issue: 05/03/2018 NRC Question No.: 20.01-17 Regulatory Basis:
10 CFR 52.47(a)(2) requires that a standard design certification applicant provide a description and analysis of the structures, systems, and components (SSCs) of the facility, with emphasis upon performance requirements, the bases, with technical justification therefor, upon which these requirements have been established, and the evaluations required to show that safety functions will be accomplished. In SECY 12-0025, the staff provided the Commission with proposed orders requiring mitigation strategies for beyond-design-basis external events to be issued to all power reactor licensees and holders of construction permits. In the paper, the staff indicated that for New Reactors that are currently under active staff review, the staff plans to ensure that the Commission-approved Fukushima recommended actions are addressed prior to licensing. On March 12, 2012, the NRC issued Orders EA-12-049 requiring operating nuclear plants to develop and implement strategies that will allow them to cope without ac power for an indefinite amount of time. The strategies must ensure that the reactor core and spent fuel pool are adequately cooled, and containment function is maintained. Currently the NRC is using JLD-ISG-2012-01, Compliance with Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, which endorses NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide, as guidance for review of how a reactor design responds to an external beyond-design-basis event. The Commission is currently proposing to amend its regulations to establish regulatory requirements for nuclear power reactor applicants and licensees to mitigate beyond-design- basis events (FRN Vol. 80, No. 219 pages 70610-701647, dated November 13, 2015),
and such rule would put the responsibility of addressing the plant response to a beyond-design-basis to the COL applicant. Because the rule is not yet final and there is not an SRP or DSRS section covering this chapter, the staff is using the JLD-ISG-2012-01 guidance to review this chapter.
NuScale Nonproprietary
Background:
During the Chapter 20.1 audit, the staff reviewed the station blackout transient analysis, which includes analytic results in support of the Extended Loss of AC Power (ELAP) conclusions in FSAR Chapter 20, and observed large fluctuations of the following parameters:
Steam generator water level from 18 - 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> during DHRS operation and from 24 - 47 hours5.439815e-4 days <br />0.0131 hours <br />7.771164e-5 weeks <br />1.78835e-5 months <br /> during ECCS operation, Energy transfer rates from 18 - 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, ECCS flow rates from 24 - 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, Core exit and lower riser void fractions form 18 - 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> during DHRS operation, and 24-72 hours during ECCS operation, and Core temperatures from 18 - 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
DHRS flow rate from 18 - 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
Request:
The staff requests the applicant to:
- 1. Identify and describe in sufficient detail the mechanism(s) responsible for the large fluctuations during DHRS operation from 18 - 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and
- 2. Identify and describe in sufficient detail the mechanism(s) responsible for the large fluctuations during ECCS operation, after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, for the parameters identified above, and
- 3. Provide an explanation of the effects on the core parameters due to these fluctuations.
NuScale Response:
The original response to RAI 9486, question 20.01-17 was submitted in NuScale Letter RAIO-0618-60652, dated June 28, 2018. The response answered the Staffs three questions.
Subsequent audit calls with NRC were held and as a result of audit calls, the NRC asked NuScale to docket the supporting documentation on riser uncovery during an extended loss of ac power (ELAP) in a supplemental response. The original response is supplemented with the information below.
Following a reactor scram, normal operating procedure will ensure reactor coolant system (RCS) temperature and inventory are kept sufficiently high by using secondary plant systems and makeup injection to maintain level in the pressurizer. However, when the module is under extended decay heat removal system (DHRS) cooling with no makeup injection available, (e.g.,
during a loss of all electrical power, as described in FSAR Chapter 20), the primary coolant NuScale Nonproprietary
could shrink below the top of the riser and disrupt the normal RCS circulation path. This scenario is referred to as riser uncovery. The following topics related to riser uncovery were discussed in the response to RAI 9508, question 15-7S1 submitted in NuScale letter RAIO-0319-64867, dated March 14, 2019: riser uncovery phenomena, NRELAP5 1D modeling of riser uncovery, DHRS performance, and core critical heat flux (CHF) and criticality potential during riser uncovery.
The RAI 9508 supplemental response concluded that:
The self-balancing mechanism of the decay heat removal system heat removal during riser uncovery is understood, The applied 1D riser and downcomer models are sufficient to demonstrate equilibrium is reached between heat removal and decay heat, and There is no safety concern during riser uncovery, with core CHF and fuel cladding temperatures showing significant margin to safety limits, and the core remaining subcritical.
These conclusions, which were applicable for the long term cooling conditions to demonstrate the core cooling ability of the ECCS (Emergency Core Cooling System) for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> after loss-of-coolant accidents (LOCA) and Non-LOCA events, are equally applicable for loss of electrical power conditions, which are analyzed using less conservative parameters than FSAR Chapter 15 events.
Impact on DCA:
There are no impacts to the DCA as a result of this response.
NuScale Nonproprietary