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| number = ML18012A308
| number = ML18012A308
| issue date = 01/18/2018
| issue date = 01/18/2018
| title = Public Meeting Summary of the December 19, 2017, Public Meeting with Nuscale Power, LLC Related to Chapters 7
| title = Public Meeting Summary of the December 19, 2017, Public Meeting with NuScale Power, LLC Related to Chapters 7
| author name = Tabatabai O
| author name = Tabatabai O
| author affiliation = NRC/NRO/DNRL/LB1
| author affiliation = NRC/NRO/DNRL/LB1
| addressee name = Lee S S
| addressee name = Lee S
| addressee affiliation = NRC/NRO/DNRL/LB1
| addressee affiliation = NRC/NRO/DNRL/LB1
| docket = 05200048
| docket = 05200048
Line 15: Line 15:


=Text=
=Text=
{{#Wiki_filter:January 18, 2018  
{{#Wiki_filter:January 18, 2018 MEMORANDUM TO:                 Samuel S. Lee, Chief Licensing Branch 1 Division of New Reactor Licensing Office of New Reactors FROM:                           Omid Tabatabai, Senior Project Manager     /RA/
 
Licensing Branch 1 Division of New Reactor Licensing Office of New Reactors
MEMORANDUM TO:   Samuel S. Lee, Chief Licensing Branch 1 Division of New Reactor Licensing Office of New Reactors FROM:   Omid Tabatabai, Senior Project Manager  
/RA/     Licensing Branch 1 Division of New Reactor Licensing Office of New Reactors  


==SUBJECT:==
==SUBJECT:==
Line 24: Line 22:
==SUMMARY==
==SUMMARY==
OF THE DECEMBER 19, 2017, PUBLIC MEETING WITH NUSCALE POWER, LLC, TO DISCUSS THE U.S.
OF THE DECEMBER 19, 2017, PUBLIC MEETING WITH NUSCALE POWER, LLC, TO DISCUSS THE U.S.
NUCLEAR REGULATORY COMMISSION STAFF QUESTIONS RELATED TO THE INITIAL TEST PROGRAM FOR THE ENABLE NONSAFETY CONTROL SWITCH AND VARIOUS PROTECTION SYSTEM TESTS  
NUCLEAR REGULATORY COMMISSION STAFF QUESTIONS RELATED TO THE INITIAL TEST PROGRAM FOR THE ENABLE NONSAFETY CONTROL SWITCH AND VARIOUS PROTECTION SYSTEM TESTS On December 19, 2017, representatives of the U.S. Nuclear Regulatory Commission (NRC) and NuScale Power, LLC (NuScale) held a public teleconference meeting to discuss the NRC staffs questions related to the Initial Test Program for the Enable Nonsafety Control Switch and various protection system tests, as they relate to the Chapter 7, Instrumentation and Controls, of the NuScale Design Certification Application (DCA). A complete copy of NuScales DCA is available on the NRC public Web page at https://www.nrc.gov/reactors/new-reactors/design-cert/nuscale/documents.html. captures the summary of the topics discussed during the teleconference. The agenda and list of meeting attendees are included in Enclosures 2 and 3, respectively. The meeting notice for this meeting is available in Agencywide Documents Access and Management System under Accession No. ML17292B031.
 
Docket No. 52-048
On December 19, 2017, representatives of the U.S. Nuclear Regulatory Commission (NRC) and NuScale Power, LLC (NuScale) held a public teleconference meeting to discuss the NRC staff's questions related to the Initial Test Program for the Enable Nonsafety Control Switch and various protection system tests, as they relate to the Chapter 7, "Instrumentation and Controls,"
of the NuScale Design Certification Application (DCA). A complete copy of NuScale's DCA is available on the NRC public Web page at https://www.nrc.gov/reactors/new-reactors/design-cert/nuscale/documents.html. Enclosure 1 captures the summary of the topics discussed during the teleconference. The agenda and list of meeting attendees are included in Enclosures 2 and 3, respectively. The meeting notice for this meeting is available in Agencywide Documents Access and Management System under Accession No. ML17292B031.  
 
Docket No. 52-048


==Enclosures:==
==Enclosures:==
: 1. Meeting Summary
: 1. Meeting Summary
: 2. Agenda 3. Attendee  
: 2. Agenda
: 3. Attendee CONTACT: Omid Tabatabai, NRO/DNRL 301-415-6616


CONTACT:  Omid Tabatabai, NRO/DNRL              301-415-6616
ML18012A308         *via email                 NRC-001 OFFICE  NRO/DNRL/LB1:PM NRO/DNRL/LB1:LA NRO/DEI/ICE:BC* NRO/DCIP/QAB3:BC* NRO/DNRL/LB1:PM NAME     OTabatabai       MMoore         IJung           KKavanagh         OTabatabai DATE     1/11/2018       1/17/2018     1/17/2018       1/18/2018         1/18/2018 U.S. NUCLEAR REGULATORY COMMISSION
 
ML18012A308     *via email   NRC-001OFFICE NRO/DNRL/LB1:PM NRO/DNRL/LB1:LA NRO/DE I/ICE:BC* NRO/DCIP/QAB3:BC* NRO/DNRL/LB1:PM NAME OTabatabai MMoore IJung KKavanagh OTabatabai DATE 1/11/2018 1/17/2018 1/17/2018 1/18/2018 1/18/2018 Enclosure 1 U.S. NUCLEAR REGULATORY COMMISSION  


==SUMMARY==
==SUMMARY==
OF THE DECEMBER 19, 2017, TELECONFERENCE WITH NUSCALE POWER, LLC
OF THE DECEMBER 19, 2017, TELECONFERENCE WITH NUSCALE POWER, LLC
: 1. System Level Test No. 63-3 The U.S. Nuclear Regulatory Commission (NRC) staff discussed NuScale's Power, LLC (NuScale) Initial Test Program (ITP). Spec ifically, the NRC staff discussed Table 14.2-63, "Module Protection System Test," No. 63-3. This test verifies interlock and permissive functions. During the public meeting, the NRC staff asked the applicant to provide an  
: 1. System Level Test No. 63-3 The U.S. Nuclear Regulatory Commission (NRC) staff discussed NuScales Power, LLC (NuScale) Initial Test Program (ITP). Specifically, the NRC staff discussed Table 14.2-63, Module Protection System Test, No. 63-3. This test verifies interlock and permissive functions. During the public meeting, the NRC staff asked the applicant to provide an explanation as to why the F-1 interlock is not included in Design Control Document (DCD), Part 2 - Tier 1. The applicant stated that a change had been processed and communicated to the NRC staff for DCD, Part 2 - Tier 1, Table 2.5-2, which now includes the F-1 interlock. The applicant agreed to provide the reference of this change to the NRC staff.
: 2. System Level Test No. 63-4 The NRC staff discussed Table 14.2-63, No. 63-4. This test method states that all combinations of the two-out-of-four logic are tested for each reactor trip and engineered safety features (ESF) actuation. During the public meeting, the NRC staff asked whether all combinations of logic included logic combinations of the permissive signal being in and out. The applicant stated that the logic combinations including the permissive were not included and will be tested during the site acceptance testing (SAT). Completion of SAT by the combined license holder is encompassed in inspections, tests, analyses, and acceptance criteria (ITAAC) 2.5.2 (DCD, Part 2 - Tier 1, Section 2.5, Table 2.5-7, Item No. 1). The NRC staff determined that further discussion is needed on whether a prerequisite is required for the preoperational test that depends upon the completion of SAT activities.
: 3. System Level Test No. 63-6 The NRC staff discussed Table 14.2-63, No. 63-6. This test verifies manual and automatic actuation of the ESF equipment. During the public meeting, the NRC staff asked the applicant to provide an explanation on how all functionality of the enable nonsafety switch is being tested. The applicant proposed to revise Test No. 63-6 to add a step after item (ii).b. to attempt to operate the ESF equipment from the main control room (MCR), thus testing that control from the MCR via the Module Control System cannot be completed unless the enable nonsafety control switch is used. The applicant agreed to provide a markup to System Level Test No. 63-6 by January 2018 that describes this clarification. Additionally, the applicant stated that the rest of the MPS-related MCR control functions will be tested during SAT.
: 4. System Level Test No. 63-7 The NRC staff discussed Table 14.2-63: No. 63-7. This test verifies stroke time of containment isolation valves (CIVs). Test Method refers to Table 6.2-10, however the NRC staff was not able to find Table 6.2-10 in the NuScale design certification application. Table 6.2-4, Containment Penetrations, list stroke times for CIVs, but does not appear to include all CIVs. During the public meeting, the NRC staff asked the applicant what the correct reference for the CIV stroke times should be. The applicant stated that the correct table is DCD Tier 2, Enclosure 1


explanation as to why the F-1 interlock is not included in Design Control Document (DCD), Part 2 - Tier 1. The applicant stated that a change had been processed and communicated to the NRC staff for DCD, Part 2 - Tier 1, Table 2.5-2, which now includes the F-1 interlock. The applicant agreed to provide the reference of this change to the NRC staff.
Table 6.2-5, Containment Isolation Valve Design Information. The applicant agreed to provide a markup to System Level Test No. 63-7 by January 2018 that describes this clarification.
: 2. System Level Test No. 63-4 The NRC staff discussed Table 14.2-63, No. 63-4. This test method states that all combinations of the two-out-of-four logic are tested for each reactor trip and engineered safety features (ESF) actuation. During the public meeting, the NRC staff asked whether all combinations of logic included logic combinations of the permissive signal being in and out. The applicant stated that the logic combinations including the permissive were not included and will be tested during the site acceptance testing (SAT). Completion of SAT by the combined license holder is
: 5. System Level Test No. 63-8 The NRC staff discussed Table 14.2-63, No. 63-8. This test verifies response times for ESF and reactor trip functions. Response time from signal generation to component actuation is broken up into two tests. Test No. 63-7 tests the stoke time of the CIVs, while Test No. 63-8 test the de-energization of the solenoid valves. DCD Tier 2, Table 7.1-6, Design Basis Event Actuation Delays Assumed in the Plant Safety Analysis, list the actuation delays times. It is unclear to the NRC staff on how the applicant is testing the response time from signal generation to component actuation. During the public meeting, the NRC staff asked the applicant where the verification of the complete system response time was completed. The applicant is to provide a response at a later date.
: 6. System Level Test No. 63-9 The NRC staff discussed Table 14.2-63, No. 63-9. This test verifies controls in place for tunable parameters. The NRC staff discussed the following three topics with the applicant:
a) Test does not define which parameters can be modified.
b) Test does not verify indication in control room for when the maintenance work station communication is enabled.
c) Test does not include controls in place regarding calibration of the module protection system.
During the public meeting, the applicant committed to provide the NRC staff with a discussion on how tunable parameters are defined and whether Test No. 63-9 includes the correct reference for actions required for an operator to modify tunable parameters.
: 7. Plant Protection System Test No. 64 The NRC staff discussed Table 14.2-64, Plant Protection System (PPS) Test No. 64. This test verifies functionality of the PPS for control room habitability system. DCD Tier 2, Chapter 7 does not describe functions of the PPS. During the public meeting, the NRC staff asked the applicant to provide a reference to where the PPS functions are described. The applicant stated that the PPS functions are described in DCD Tier 2, Section 9.4, Air Conditioning, Heating, Cooling, and Ventilation System, but would verify upon receipt of NRCs question via email.
2


encompassed in inspections, tests, analyses, and acceptance criteria (ITAAC) 2.5.2 (DCD, Part 2 - Tier 1, Section 2.5, Table 2.5-7, Item No. 1). The NRC staff determined that further discussion is needed on whether a prerequisite is required for the preoperational test that depends upon the completion of SAT activities.
U.S. NUCLEAR REGULATORY COMMISSION
: 3. System Level Test No. 63-6 The NRC staff discussed Table 14.2-63, No. 63-6. This test verifies manual and automatic actuation of the ESF equipment. During the public meeting, the NRC staff asked the applicant
 
to provide an explanation on how all functionality of the enable nonsafety switch is being tested. The applicant proposed to revise Test No. 63-6 to add a step after item (ii).b. to attempt to operate the ESF equipment from the main control room (MCR), thus testing that control from the MCR via the Module Control System cannot be completed unless the enable nonsafety control switch is used. The applicant agreed to provide a markup to System Level Test No. 63-6 by January 2018 that describes this clarification. Additionally, the applicant stated that the rest of the MPS-related MCR control functions will be tested during SAT.
: 4. System Level Test No. 63-7 The NRC staff discussed Table 14.2-63:  No. 63-7. This test verifies stroke time of containment isolation valves (CIVs). Test Method refers to Table 6.2-10, however the NRC staff was not able to find Table 6.2-10 in the NuScale design certification application. Table 6.2-4, "Containment Penetrations," list stroke times for CIVs, but does not appear to include all CIVs. During the public meeting, the NRC staff asked the applicant what the correct reference for the CIV stroke times should be. The applicant stated that the correct table is DCD Tier 2, 2  Table 6.2-5, "Containment Isolation Valve Design Information."  The applicant agreed to provide a markup to System Level Test No. 63-7 by January 2018 that describes this clarification.
: 5. System Level Test No. 63-8 The NRC staff discussed Table 14.2-63, No. 63-8. This test verifies response times for ESF and reactor trip functions. Response time from signal generation to component actuation is broken up into two tests. Test No. 63-7 tests the stoke time of the CIVs, while Test No. 63-8 test the de-energization of the solenoid valves. DCD Tier 2, Table 7.1-6, "Design Basis Event Actuation Delays Assumed in the Plant Safety Analysis," list the actuation delays times. It is unclear to the NRC staff on how the applicant is testing the response time from signal generation to component actuation. During the public meeting, the NRC staff asked the applicant where the verification of the complete system response time was completed. The applicant is to provide a response at a later date.
: 6. System Level Test No. 63-9 The NRC staff discussed Table 14.2-63, No. 63-9. This test verifies controls in place for tunable parameters. The NRC staff discussed the fo llowing three topics with the applicant:
a) Test does not define which parameters can be modified. b) Test does not verify indication in control room for when the maintenance work station communication is enabled. c) Test does not include controls in place regarding calibration of the module protection system. During the public meeting, the applicant committ ed to provide the NRC staff with a discussion on how tunable parameters are defined and whether Test No. 63-9 includes the correct reference for actions required for an operator to modify tunable parameters.
: 7. Plant Protection System Test No. 64 The NRC staff discussed Table 14.2-64, "Plant Protection System (PPS) Test No. 64."  This test verifies functionality of the PPS for control room habitability system. DCD Tier 2, Chapter 7 does not describe functions of the PPS. During the public meeting, the NRC staff asked the applicant to provide a reference to where the PPS functions are described. The applicant stated that the PPS functions are described in DCD Tier 2, Section 9.4, "Air Conditioning, Heating, Cooling, and Ventilation System," but would verify upon receipt of NRC's question via email. 
 
Enclosure 2 U.S. NUCLEAR REGULATORY COMMISSION  


==SUMMARY==
==SUMMARY==
OF THE DECEMBER 19, 2017, TELECONFERENCE WITH NUSCALE POWER, LLC MEETING AGENDA 1:00-1:10 p.m. Meeting Introductions 1:10-1:20 p.m. Discussion of Initial Test Program for the Enable Nonsafety Control Switch 1:20-1:50 p.m. Discussion of Various Module Protection System Tests 1:50-2:00 p.m. Meeting Conclusion  
OF THE DECEMBER 19, 2017, TELECONFERENCE WITH NUSCALE POWER, LLC MEETING AGENDA 1:00-1:10 p.m.       Meeting Introductions Discussion of Initial Test Program for the Enable 1:10-1:20 p.m.
Nonsafety Control Switch 1:20-1:50 p.m.       Discussion of Various Module Protection System Tests 1:50-2:00 p.m.       Meeting Conclusion Enclosure 2


Enclosure 3 U.S. NUCLEAR REGULATORY COMMISSION  
U.S. NUCLEAR REGULATORY COMMISSION


==SUMMARY==
==SUMMARY==
OF THE DECEMBER 19, 2017, TELECONFERENCE WITH NUSCALE POWER, LLC LIST OF ATTENDEES
OF THE DECEMBER 19, 2017, TELECONFERENCE WITH NUSCALE POWER, LLC LIST OF ATTENDEES NuScale Carl Dumsday Steve Pope Steve Mirsky Scott Patterson Rufino Ayala Chris Maxwell NRC Staff Luis Betancourt Dinesh Taneja Joseph Ashcraft Ashley Ferguson Aaron Armstrong Taylor Lamb Enclosure 3}}
 
NuScale Carl Dumsday Steve Pope Steve Mirsky  
 
Scott Patterson  
 
Rufino Ayala Chris Maxwell NRC Staff Luis Betancourt Dinesh Taneja Joseph Ashcraft Ashley Ferguson Aaron Armstrong Taylor Lamb}}

Latest revision as of 19:50, 3 February 2020

Public Meeting Summary of the December 19, 2017, Public Meeting with NuScale Power, LLC Related to Chapters 7
ML18012A308
Person / Time
Site: NuScale
Issue date: 01/18/2018
From: Omid Tabatabai
NRC/NRO/DNRL/LB1
To: Samson Lee
NRC/NRO/DNRL/LB1
Tabatabai O
References
Download: ML18012A308 (6)


Text

January 18, 2018 MEMORANDUM TO: Samuel S. Lee, Chief Licensing Branch 1 Division of New Reactor Licensing Office of New Reactors FROM: Omid Tabatabai, Senior Project Manager /RA/

Licensing Branch 1 Division of New Reactor Licensing Office of New Reactors

SUBJECT:

SUMMARY

OF THE DECEMBER 19, 2017, PUBLIC MEETING WITH NUSCALE POWER, LLC, TO DISCUSS THE U.S.

NUCLEAR REGULATORY COMMISSION STAFF QUESTIONS RELATED TO THE INITIAL TEST PROGRAM FOR THE ENABLE NONSAFETY CONTROL SWITCH AND VARIOUS PROTECTION SYSTEM TESTS On December 19, 2017, representatives of the U.S. Nuclear Regulatory Commission (NRC) and NuScale Power, LLC (NuScale) held a public teleconference meeting to discuss the NRC staffs questions related to the Initial Test Program for the Enable Nonsafety Control Switch and various protection system tests, as they relate to the Chapter 7, Instrumentation and Controls, of the NuScale Design Certification Application (DCA). A complete copy of NuScales DCA is available on the NRC public Web page at https://www.nrc.gov/reactors/new-reactors/design-cert/nuscale/documents.html. captures the summary of the topics discussed during the teleconference. The agenda and list of meeting attendees are included in Enclosures 2 and 3, respectively. The meeting notice for this meeting is available in Agencywide Documents Access and Management System under Accession No. ML17292B031.

Docket No.52-048

Enclosures:

1. Meeting Summary
2. Agenda
3. Attendee CONTACT: Omid Tabatabai, NRO/DNRL 301-415-6616

ML18012A308 *via email NRC-001 OFFICE NRO/DNRL/LB1:PM NRO/DNRL/LB1:LA NRO/DEI/ICE:BC* NRO/DCIP/QAB3:BC* NRO/DNRL/LB1:PM NAME OTabatabai MMoore IJung KKavanagh OTabatabai DATE 1/11/2018 1/17/2018 1/17/2018 1/18/2018 1/18/2018 U.S. NUCLEAR REGULATORY COMMISSION

SUMMARY

OF THE DECEMBER 19, 2017, TELECONFERENCE WITH NUSCALE POWER, LLC

1. System Level Test No. 63-3 The U.S. Nuclear Regulatory Commission (NRC) staff discussed NuScales Power, LLC (NuScale) Initial Test Program (ITP). Specifically, the NRC staff discussed Table 14.2-63, Module Protection System Test, No. 63-3. This test verifies interlock and permissive functions. During the public meeting, the NRC staff asked the applicant to provide an explanation as to why the F-1 interlock is not included in Design Control Document (DCD), Part 2 - Tier 1. The applicant stated that a change had been processed and communicated to the NRC staff for DCD, Part 2 - Tier 1, Table 2.5-2, which now includes the F-1 interlock. The applicant agreed to provide the reference of this change to the NRC staff.
2. System Level Test No. 63-4 The NRC staff discussed Table 14.2-63, No. 63-4. This test method states that all combinations of the two-out-of-four logic are tested for each reactor trip and engineered safety features (ESF) actuation. During the public meeting, the NRC staff asked whether all combinations of logic included logic combinations of the permissive signal being in and out. The applicant stated that the logic combinations including the permissive were not included and will be tested during the site acceptance testing (SAT). Completion of SAT by the combined license holder is encompassed in inspections, tests, analyses, and acceptance criteria (ITAAC) 2.5.2 (DCD, Part 2 - Tier 1, Section 2.5, Table 2.5-7, Item No. 1). The NRC staff determined that further discussion is needed on whether a prerequisite is required for the preoperational test that depends upon the completion of SAT activities.
3. System Level Test No. 63-6 The NRC staff discussed Table 14.2-63, No. 63-6. This test verifies manual and automatic actuation of the ESF equipment. During the public meeting, the NRC staff asked the applicant to provide an explanation on how all functionality of the enable nonsafety switch is being tested. The applicant proposed to revise Test No. 63-6 to add a step after item (ii).b. to attempt to operate the ESF equipment from the main control room (MCR), thus testing that control from the MCR via the Module Control System cannot be completed unless the enable nonsafety control switch is used. The applicant agreed to provide a markup to System Level Test No. 63-6 by January 2018 that describes this clarification. Additionally, the applicant stated that the rest of the MPS-related MCR control functions will be tested during SAT.
4. System Level Test No. 63-7 The NRC staff discussed Table 14.2-63: No. 63-7. This test verifies stroke time of containment isolation valves (CIVs). Test Method refers to Table 6.2-10, however the NRC staff was not able to find Table 6.2-10 in the NuScale design certification application. Table 6.2-4, Containment Penetrations, list stroke times for CIVs, but does not appear to include all CIVs. During the public meeting, the NRC staff asked the applicant what the correct reference for the CIV stroke times should be. The applicant stated that the correct table is DCD Tier 2, Enclosure 1

Table 6.2-5, Containment Isolation Valve Design Information. The applicant agreed to provide a markup to System Level Test No. 63-7 by January 2018 that describes this clarification.

5. System Level Test No. 63-8 The NRC staff discussed Table 14.2-63, No. 63-8. This test verifies response times for ESF and reactor trip functions. Response time from signal generation to component actuation is broken up into two tests. Test No. 63-7 tests the stoke time of the CIVs, while Test No. 63-8 test the de-energization of the solenoid valves. DCD Tier 2, Table 7.1-6, Design Basis Event Actuation Delays Assumed in the Plant Safety Analysis, list the actuation delays times. It is unclear to the NRC staff on how the applicant is testing the response time from signal generation to component actuation. During the public meeting, the NRC staff asked the applicant where the verification of the complete system response time was completed. The applicant is to provide a response at a later date.
6. System Level Test No. 63-9 The NRC staff discussed Table 14.2-63, No. 63-9. This test verifies controls in place for tunable parameters. The NRC staff discussed the following three topics with the applicant:

a) Test does not define which parameters can be modified.

b) Test does not verify indication in control room for when the maintenance work station communication is enabled.

c) Test does not include controls in place regarding calibration of the module protection system.

During the public meeting, the applicant committed to provide the NRC staff with a discussion on how tunable parameters are defined and whether Test No. 63-9 includes the correct reference for actions required for an operator to modify tunable parameters.

7. Plant Protection System Test No. 64 The NRC staff discussed Table 14.2-64, Plant Protection System (PPS) Test No. 64. This test verifies functionality of the PPS for control room habitability system. DCD Tier 2, Chapter 7 does not describe functions of the PPS. During the public meeting, the NRC staff asked the applicant to provide a reference to where the PPS functions are described. The applicant stated that the PPS functions are described in DCD Tier 2, Section 9.4, Air Conditioning, Heating, Cooling, and Ventilation System, but would verify upon receipt of NRCs question via email.

2

U.S. NUCLEAR REGULATORY COMMISSION

SUMMARY

OF THE DECEMBER 19, 2017, TELECONFERENCE WITH NUSCALE POWER, LLC MEETING AGENDA 1:00-1:10 p.m. Meeting Introductions Discussion of Initial Test Program for the Enable 1:10-1:20 p.m.

Nonsafety Control Switch 1:20-1:50 p.m. Discussion of Various Module Protection System Tests 1:50-2:00 p.m. Meeting Conclusion Enclosure 2

U.S. NUCLEAR REGULATORY COMMISSION

SUMMARY

OF THE DECEMBER 19, 2017, TELECONFERENCE WITH NUSCALE POWER, LLC LIST OF ATTENDEES NuScale Carl Dumsday Steve Pope Steve Mirsky Scott Patterson Rufino Ayala Chris Maxwell NRC Staff Luis Betancourt Dinesh Taneja Joseph Ashcraft Ashley Ferguson Aaron Armstrong Taylor Lamb Enclosure 3