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| number = ML14094A275
| number = ML14094A275
| issue date = 05/19/2014
| issue date = 05/19/2014
| title = Summary of Telephone Conference Call Held on March 19, 2014, Between the U.S. Nuclear Regulatory Commission and Exelon Generation Company, LLC Concerning Draft Request for Additional Information, Set 18, Pertaining to the Byron Station and  
| title = Summary of Telephone Conference Call Held on March 19, 2014, Between the U.S. Nuclear Regulatory Commission and Exelon Generation Company, LLC Concerning Draft Request for Additional Information, Set 18, Pertaining to the Byron Station and
| author name = Robinson L R
| author name = Robinson L
| author affiliation = NRC/NRR/DLR/RPB1
| author affiliation = NRC/NRR/DLR/RPB1
| addressee name = Gallagher M P
| addressee name = Gallagher M
| addressee affiliation = Exelon Generation Co, LLC
| addressee affiliation = Exelon Generation Co, LLC
| docket = 05000454, 05000455, 05000456, 05000457
| docket = 05000454, 05000455, 05000456, 05000457
| license number =  
| license number =  
| contact person = Robinson L R, 415-4115
| contact person = Robinson L, 415-4115
| case reference number = TAC MF1879, TAC MF1880, TAC MF1881, TAC MF1882
| case reference number = TAC MF1879, TAC MF1880, TAC MF1881, TAC MF1882
| document type = Meeting Summary, Note to File incl Telcon Record, Verbal Comm, Request for Additional Information (RAI)
| document type = Meeting Summary, Note to File incl Telcon Record, Verbal Comm, Request for Additional Information (RAI)
Line 18: Line 18:


=Text=
=Text=
{{#Wiki_filter:May 19, 2014   LICENSEE: Exelon Generation Company, LLC FACILITY: Byron Station, Units 1 and 2 Braidwood Station, Units 1 and 2
{{#Wiki_filter:May 19, 2014 LICENSEE:       Exelon Generation Company, LLC FACILITY:       Byron Station, Units 1 and 2 Braidwood Station, Units 1 and 2


==SUBJECT:==
==SUBJECT:==


==SUMMARY==
==SUMMARY==
OF TELEPHONE CONFERENCE CALL HELD ON MARCH 19 , 2014, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION COMPANY, LLC CONCERNING DRAFT REQUEST FOR ADDITIONAL INFORMATION, SET 18, PERTAINING TO THE BYRON STATION AND BRAIDWOOD STATION, LICENSE RENEWAL APPLICATION (TAC NOS. MF1879, MF1880, MF1881, MF1882)
OF TELEPHONE CONFERENCE CALL HELD ON MARCH 19, 2014, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION COMPANY, LLC CONCERNING DRAFT REQUEST FOR ADDITIONAL INFORMATION, SET 18, PERTAINING TO THE BYRON STATION AND BRAIDWOOD STATION, LICENSE RENEWAL APPLICATION (TAC NOS. MF1879, MF1880, MF1881, MF1882)
The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Exelon Generation Company, LLC (Exelon o r t h e applicant), held a telephone conference call on March 19 , 2014, to discuss and clarify the staff's draft request for additional information (DRAI), Set 18, concerning the Byron Station, Units 1 and 2, and the Braidwood Station, Units 1 and 2, license renewal application. The telephone conference call was useful in clarifying the intent of the staff's DRAIs.
The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Exelon Generation Company, LLC (Exelon or the applicant), held a telephone conference call on March 19, 2014, to discuss and clarify the staffs draft request for additional information (DRAI),
Enclosure 1 provides a listing of the participants, and Enclosure 2 contains a listing of the DRAIs discussed with the applicant, including a brief description on the status of the items.
Set 18, concerning the Byron Station, Units 1 and 2, and the Braidwood Station, Units 1 and 2, license renewal application. The telephone conference call was useful in clarifying the intent of the staffs DRAIs. provides a listing of the participants, and Enclosure 2 contains a listing of the DRAIs discussed with the applicant, including a brief description on the status of the items.
The applicant had an opportunity to comment on this summary.
The applicant had an opportunity to comment on this summary.
  /RA/ Lindsay Robinson, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos.
                                                /RA/
5 0-454, 50-455, 50-456, and 50
Lindsay Robinson, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-454, 50-455, 50-456, and 50-457
-457


==Enclosures:==
==Enclosures:==
: 1. List of Participants
: 1. List of Participants
: 2. List of Draft Request for Additional Information cc w/encls: Listserv
: 2. List of Draft Request for Additional Information cc w/encls: Listserv


ML14094A275
ML14094A275                                     *concurred via email OFFICE LA:DLR*             PM: RPB1:DLR BC:RPB1:DLR PM:RPB1:DLR NAME YEdmonds               LRobinson         YDiazSanabria LRobinson DATE 5/8/14                 5/14/14           5/15/14           5/19/14
    *concurred via email O FF I CE  L A: D LR* PM: RPB1:DLR BC:RPB 1: D LR  P M:RPB 1: D LR N A M E YEdmonds LRobinson YDiazSanabria LRobinson DA T E 5/8/14 5/14/14 5/15/14 5/19/14


==SUBJECT:==
==SUBJECT:==


==SUMMARY==
==SUMMARY==
OF TELEPHONE CONFERENCE CALL HELD ON MARCH 19 , 2014, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION COMPANY, LLC CONCERNING DRAFT REQUEST FOR ADDITIONAL INFORMATION, SET 18, PERTAINING TO THE BYRON STATION AND BRAIDWOOD STATION, LICENSE RENEWAL APPLICATION , SET 18 (TAC NOS. MF1879, MF1880, MF1881, MF1882)
OF TELEPHONE CONFERENCE CALL HELD ON MARCH 19, 2014, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION COMPANY, LLC CONCERNING DRAFT REQUEST FOR ADDITIONAL INFORMATION, SET 18, PERTAINING TO THE BYRON STATION AND BRAIDWOOD STATION, LICENSE RENEWAL APPLICATION, SET 18 (TAC NOS. MF1879, MF1880, MF1881, MF1882)
DISTRIBUTION EMAIL: PUBLIC RidsNrrDlr Resource RidsNrrDlrRpb1 Resource RidsNrrDlrRar b Resource RidsOgcMailCenter RidsNrrPMByron Resource RidsNrrPMBraidwood Resource
DISTRIBUTION EMAIL:
----------------------------------
PUBLIC RidsNrrDlr Resource RidsNrrDlrRpb1 Resource RidsNrrDlrRarb Resource RidsOgcMailCenter RidsNrrPMByron Resource RidsNrrPMBraidwood Resource LRobinson DMcIntyre, OPA EDuncan, RIII JBenjamin, RIII AGarmoe, RIII JMcGhee, RIII JRobbins, RIII VMitlyng, RIII PChandrathil, RIII
LRobinson DMcIntyre, OPA EDuncan, RIII JBenjamin, RIII AGarmoe, RIII JMcGhee, RIII JRobbins, RIII VMitlyng, RIII PChandrathil, RIII ENCLOSURE 1 TELEPHONE CONFERENCE CALL BYRON STATION, UNITS 1 AND 2, AND BRAIDWOOD STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION LIST OF PARTICIPANTS March 19, 2014 P A R T I C I P A N T S A F F I L I A T IO N S  Lindsay Robinson U.S. Nuclea r R e gula t o r y Co mmissio n (NRC) William Holston NRC John Wise NRC Allen Hiser NRC Aloysius Obodoako NRC Ken Karwoski NRC John Hufnagel Exelon Generating Company, LLC (Exelon)
 
Don Warfel Exelon Al Fulvio Exelon Albert Piha Exelon Gary Becknell Exelon Al Fulvio Exelon Casey Muggleston Exelon Don Brindle Exelon ENCLOSURE 2 DRAFT REQUEST FOR ADDITIONAL INFORMATION BYRON STATION, UNITS 1 AND 2, AND BRAIDWOOD STATION, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION March 19, 2014 The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Exelon Generation Company, LLC (Exelon o r t h e applicant), held a telephone conference call on March 19 , 2014, to discuss and clarify the following draft request for additional information (DRAI), Set 18, concerning the Byron Station, Units 1 and 2, and the Braidwood Station, Units 1 and 2, license renewal application (LRA).
TELEPHONE CONFERENCE CALL BYRON STATION, UNITS 1 AND 2, AND BRAIDWOOD STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION LIST OF PARTICIPANTS March 19, 2014 PARTICIPANTS                          AFFILIATIONS Lindsay Robinson                       U.S. Nuclear Regulatory Commission (NRC)
DRAI 3.1.2.3.4
William Holston                       NRC John Wise                             NRC Allen Hiser                           NRC Aloysius Obodoako                     NRC Ken Karwoski                           NRC John Hufnagel                         Exelon Generating Company, LLC (Exelon)
-1 Applicability
Don Warfel                             Exelon Al Fulvio                             Exelon Albert Piha                           Exelon Gary Becknell                         Exelon Al Fulvio                             Exelon Casey Muggleston                       Exelon Don Brindle                           Exelon ENCLOSURE 1
:
 
DRAFT REQUEST FOR ADDITIONAL INFORMATION BYRON STATION, UNITS 1 AND 2, AND BRAIDWOOD STATION, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION March 19, 2014 The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Exelon Generation Company, LLC (Exelon or the applicant), held a telephone conference call on March 19, 2014, to discuss and clarify the following draft request for additional information (DRAI), Set 18, concerning the Byron Station, Units 1 and 2, and the Braidwood Station, Units 1 and 2, license renewal application (LRA).
DRAI 3.1.2.3.4-1 Applicability:
Byron and Braidwood, Unit 1
Byron and Braidwood, Unit 1


===Background===
==Background:==
License renewal application (LRA) Table 3.1.2
 
-4 addresses loss of fracture toughness in steam generator internal structural supports exposed to treated water > 482
License renewal application (LRA) Table 3.1.2-4 addresses loss of fracture toughness in steam generator internal structural supports exposed to treated water > 482 ºF at Byron and Braidwood Stations, Unit 1. The LRA states that the steam generator tube support lattice bar is fabricated from SA-240 410S martensitic stainless steel (SS), and the steam generator tube support lattice bar attachment component is fabricated from SA-351 CF3M cast austenitic SS. The LRA Table provides a note H for this component, material, and environment. Note H states that this aging effect (i.e., loss of fracture toughness) is not in NUREG-1801 for the component, material, and environment combination. Visual inspections and eddy current testing were proposed to manage this degradation mechanism.
ºF at Byron and Braidwood Stations, Unit 1. The LRA states that the steam generator tube support lattice bar is fabricated from SA-240 410S martensitic stainless steel (SS), and the steam generator tube support lattice bar attachment component is fabricated from SA
Issue:
-351 CF3M cast austenitic SS. The LRA Table provides a note H for this component, material, and environment. Note H states that this aging effect (i.e., loss of fracture toughness) is not in NUREG
The staff needs additional information concerning the degradation mechanism and the component/environment to ascertain whether the proposed aging management program is adequate.
-1801 for the component, material, and environment combination. Visual inspections and eddy current testing were proposed to manage this degradation mechanism.
Request:
Issue: The staff needs additional information concerning the degradation mechanism and the component/environment to ascertain whether the proposed aging management program is adequate. Request: Please provide a description briefly discuss the nature of these components (including their function) and the extent to which they are used throughout the steam generator; a sketch/diagram may be useful. Please discuss the susceptibility of these particular components to thermal aging embrittlement (
Please provide a description briefly discuss the nature of these components (including their function) and the extent to which they are used throughout the steam generator; a sketch/diagram may be useful. Please discuss the susceptibility of these particular components to thermal aging embrittlement (


==Reference:==
==Reference:==
Letter from C.I. Grimes, NRC, to Douglas J. Walters, Nuclear Energy Institute, License Renewal Issue No. 98
Letter from C.I. Grimes, NRC, to Douglas J.
-0030, "Thermal Aging Embrittlement of Cast Stainless Steel Components," dated May 19, 2000, ML003717179). Discuss how visual inspections and eddy current testing will be adequate to ensure any loss of fracture toughness that does occur will be limited such that the component will continue to be able to perform its intended safety function during normal operation, transient, and accident conditions. That is, discuss the possibility that the loss of fracture toughness would render the component incapable of performing its function without the component showing any visual evidence of cracking, deformation, or damage.
Walters, Nuclear Energy Institute, License Renewal Issue No. 98-0030, Thermal Aging Embrittlement of Cast Stainless Steel Components, dated May 19, 2000, ML003717179).
Discussion
Discuss how visual inspections and eddy current testing will be adequate to ensure any loss of fracture toughness that does occur will be limited such that the component will continue to be able to perform its intended safety function during normal operation, transient, and accident conditions. That is, discuss the possibility that the loss of fracture toughness would render the component incapable of performing its function without the component showing any visual evidence of cracking, deformation, or damage.
: The applicant requested clarification on the staff's request. The applicant requested the staff to identify the applicability of the question and whether there was a need for a sketch or diagram when discussing the steam generator components. The staff agreed to identify the applicability of the question for Byron Unit 1 and Braidwood Unit 1; and after further review, the staff agreed to remove the request for a sketch or diagram. The staff also added eddy currents to the scope of the request as indicated by the underlined portion in the Background and Request sections. All underlined portions indicated additions made to the original DRAI, and the strikethrough indicates a deletion.
ENCLOSURE 2
This question will be sent as a formal RAI titled: "RAI 3.1.2.3.4
 
-1." DRAI 3.0.3
Discussion: The applicant requested clarification on the staffs request. The applicant requested the staff to identify the applicability of the question and whether there was a need for a sketch or diagram when discussing the steam generator components. The staff agreed to identify the applicability of the question for Byron Unit 1 and Braidwood Unit 1; and after further review, the staff agreed to remove the request for a sketch or diagram. The staff also added eddy currents to the scope of the request as indicated by the underlined portion in the Background and Request sections. All underlined portions indicated additions made to the original DRAI, and the strikethrough indicates a deletion. This question will be sent as a formal RAI titled: RAI 3.1.2.3.4-1.
-3a   Applicability
DRAI 3.0.3-3a Applicability:
Byron and Braidwood
Byron and Braidwood
 
==Background:==


===Background===
In a letter dated January 13, 2014, the responses to RAIs 3.0.3-3 and B.2.1.23-1 state that cracking due to stress corrosion cracking is not an aging effect in outdoor air environments for stainless steel and aluminum components that have jacketed insulation.
:
In a letter dated January 13, 2014, the responses to RAIs 3.0.3
-3 and B.2.1.23-1 state that cracking due to stress corrosion cracking is not an aging effect in outdoor air environments for stainless steel and aluminum components that have jacketed insulation.
In regards to potential cracking due to halides in the atmosphere, the responses stated that (a) halide accumulation from the environment is not expected on components that are shielded by jacketed insulation and (b) insulated components located outdoors do not operate at high temperatures where concentration of environmental halides is expected to occur due to evaporation of any present moisture.
In regards to potential cracking due to halides in the atmosphere, the responses stated that (a) halide accumulation from the environment is not expected on components that are shielded by jacketed insulation and (b) insulated components located outdoors do not operate at high temperatures where concentration of environmental halides is expected to occur due to evaporation of any present moisture.
The Generic Aging Lessons Learned (GALL) Report aging management program (AMP) XI.M38, "External Surfaces Monitoring of Mechanical Components," recommends visual inspections for leakage to detect cracking on external surfaces that are exposed to an air environment containing halides.
The Generic Aging Lessons Learned (GALL) Report aging management program (AMP)
Issue: The staff recognizes that proper jacketing configuration can be a preventive measure for atmospheric halide intrusion; however, the staff considers a one
XI.M38, External Surfaces Monitoring of Mechanical Components, recommends visual inspections for leakage to detect cracking on external surfaces that are exposed to an air environment containing halides.
-time inspection of exposed metal for evidence of cracking as necessary to ensure that the jacketing at Byron and Braidwood is an effective barrier. Also, it is not clear to the staff why the absence of high operating temperatures would prevent moisture from evaporating on an outdoor component's surface.
Issue:
The staff recognizes that proper jacketing configuration can be a preventive measure for atmospheric halide intrusion; however, the staff considers a one-time inspection of exposed metal for evidence of cracking as necessary to ensure that the jacketing at Byron and Braidwood is an effective barrier. Also, it is not clear to the staff why the absence of high operating temperatures would prevent moisture from evaporating on an outdoor components surface.
Request:
For insulated stainless steel and aluminum components exposed to outdoor air, provide the technical justification for why exposed metal inspections for cracking are not necessary to confirm the effectiveness of the insulation jacketing in preventing halide intrusion. Alternatively, propose a baseline exposed metal inspection for cracking that may be used to validate the subsequent use of insulation-only inspections and revise the associated AMR items to include cracking as an applicable aging effect.


Discussion: The applicant requested clarification on the staffs request. Minor editorial comments were addressed. In the Background section, the staff decided to specify visual inspections, as indicated by the underlined portion in the last paragraph. It was noted by the applicant that the GALL Report AMP was improperly listed as XI.M38; it will be correctly labeled: XI.M36. The staff decided to include an additional discussion regarding potential leakage of nonwater-filled piping and piping components and agreed to revise the request per the following:
Request:
Request:
For insulated stainless steel and aluminum components exposed to outdoor air, provide the technical justification for why exposed metal inspections for cracking are not necessary to confirm the effectiveness of the insulation jacketing in preventing halide intrusion. Alternatively, propose a baseline exposed metal inspection for cracking that may be used to validate the subsequent use of insulation
For insulated stainless steel and aluminum piping and piping components exposed to outdoor air, provide the technical justification for why insulation does not need to be removed to conduct visual inspections to detect cracking in order to confirm the effectiveness of the insulation jacketing in preventing halide intrusion. Alternatively, propose to remove insulation during a baseline inspection for cracking that may be used to validate the subsequent use of insulation-only inspections and revise the associated AMR items to include cracking as an applicable aging effect. For nonwater-filled piping and piping components, state how potential leakage will be identified.
-only inspections and revise the associated AMR items to include cracking as an applicable aging effect.
This question will be sent as a formal RAI titled: RAI 3.0.3-3a.}}
Discussion
:  The applicant requested clarification on the staff's request. Minor editorial comments were addressed. In the Background section, the staff decided to specify "visual" inspections, as indicated by the underlined portion in the last paragraph. It was noted by the applicant that the GALL Report AMP was improperly listed as "XI.M38;" it will be correctly labeled: "XI.M36."  The staff decided to include an additional discussion regarding potential leakage of nonwater
-filled piping and piping components and agreed to revise the request per the following:
Request:
For insulated stainless steel and aluminum piping and piping components exposed to outdoor air, provide the technical justification for why insulation does not need to be removed to conduct visual inspections to detect cracking in order to confirm the effectiveness of the insulation jacketing in preventing halide intrusion. Alternatively, propose to remove insulation during a baseline inspection for cracking that may be used to validate the subsequent use of insulation
-
only inspections and revise the associated AMR items to include cracking as an applicable aging effect. For nonwater-filled piping and piping components, state how potential leakage will be identified.
This question will be sent as a formal RAI titled: "RAI 3.0.3
-3a."}}

Latest revision as of 22:08, 5 February 2020

Summary of Telephone Conference Call Held on March 19, 2014, Between the U.S. Nuclear Regulatory Commission and Exelon Generation Company, LLC Concerning Draft Request for Additional Information, Set 18, Pertaining to the Byron Station and
ML14094A275
Person / Time
Site: Byron, Braidwood  Constellation icon.png
Issue date: 05/19/2014
From: Robinson L
License Renewal Projects Branch 1
To: Gallagher M
Exelon Generation Co
Robinson L, 415-4115
References
TAC MF1879, TAC MF1880, TAC MF1881, TAC MF1882
Download: ML14094A275 (7)


Text

May 19, 2014 LICENSEE: Exelon Generation Company, LLC FACILITY: Byron Station, Units 1 and 2 Braidwood Station, Units 1 and 2

SUBJECT:

SUMMARY

OF TELEPHONE CONFERENCE CALL HELD ON MARCH 19, 2014, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION COMPANY, LLC CONCERNING DRAFT REQUEST FOR ADDITIONAL INFORMATION, SET 18, PERTAINING TO THE BYRON STATION AND BRAIDWOOD STATION, LICENSE RENEWAL APPLICATION (TAC NOS. MF1879, MF1880, MF1881, MF1882)

The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Exelon Generation Company, LLC (Exelon or the applicant), held a telephone conference call on March 19, 2014, to discuss and clarify the staffs draft request for additional information (DRAI),

Set 18, concerning the Byron Station, Units 1 and 2, and the Braidwood Station, Units 1 and 2, license renewal application. The telephone conference call was useful in clarifying the intent of the staffs DRAIs. provides a listing of the participants, and Enclosure 2 contains a listing of the DRAIs discussed with the applicant, including a brief description on the status of the items.

The applicant had an opportunity to comment on this summary.

/RA/

Lindsay Robinson, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-454, 50-455, 50-456, and 50-457

Enclosures:

1. List of Participants
2. List of Draft Request for Additional Information cc w/encls: Listserv

ML14094A275 *concurred via email OFFICE LA:DLR* PM: RPB1:DLR BC:RPB1:DLR PM:RPB1:DLR NAME YEdmonds LRobinson YDiazSanabria LRobinson DATE 5/8/14 5/14/14 5/15/14 5/19/14

SUBJECT:

SUMMARY

OF TELEPHONE CONFERENCE CALL HELD ON MARCH 19, 2014, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION COMPANY, LLC CONCERNING DRAFT REQUEST FOR ADDITIONAL INFORMATION, SET 18, PERTAINING TO THE BYRON STATION AND BRAIDWOOD STATION, LICENSE RENEWAL APPLICATION, SET 18 (TAC NOS. MF1879, MF1880, MF1881, MF1882)

DISTRIBUTION EMAIL:

PUBLIC RidsNrrDlr Resource RidsNrrDlrRpb1 Resource RidsNrrDlrRarb Resource RidsOgcMailCenter RidsNrrPMByron Resource RidsNrrPMBraidwood Resource LRobinson DMcIntyre, OPA EDuncan, RIII JBenjamin, RIII AGarmoe, RIII JMcGhee, RIII JRobbins, RIII VMitlyng, RIII PChandrathil, RIII

TELEPHONE CONFERENCE CALL BYRON STATION, UNITS 1 AND 2, AND BRAIDWOOD STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION LIST OF PARTICIPANTS March 19, 2014 PARTICIPANTS AFFILIATIONS Lindsay Robinson U.S. Nuclear Regulatory Commission (NRC)

William Holston NRC John Wise NRC Allen Hiser NRC Aloysius Obodoako NRC Ken Karwoski NRC John Hufnagel Exelon Generating Company, LLC (Exelon)

Don Warfel Exelon Al Fulvio Exelon Albert Piha Exelon Gary Becknell Exelon Al Fulvio Exelon Casey Muggleston Exelon Don Brindle Exelon ENCLOSURE 1

DRAFT REQUEST FOR ADDITIONAL INFORMATION BYRON STATION, UNITS 1 AND 2, AND BRAIDWOOD STATION, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION March 19, 2014 The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Exelon Generation Company, LLC (Exelon or the applicant), held a telephone conference call on March 19, 2014, to discuss and clarify the following draft request for additional information (DRAI), Set 18, concerning the Byron Station, Units 1 and 2, and the Braidwood Station, Units 1 and 2, license renewal application (LRA).

DRAI 3.1.2.3.4-1 Applicability:

Byron and Braidwood, Unit 1

Background:

License renewal application (LRA) Table 3.1.2-4 addresses loss of fracture toughness in steam generator internal structural supports exposed to treated water > 482 ºF at Byron and Braidwood Stations, Unit 1. The LRA states that the steam generator tube support lattice bar is fabricated from SA-240 410S martensitic stainless steel (SS), and the steam generator tube support lattice bar attachment component is fabricated from SA-351 CF3M cast austenitic SS. The LRA Table provides a note H for this component, material, and environment. Note H states that this aging effect (i.e., loss of fracture toughness) is not in NUREG-1801 for the component, material, and environment combination. Visual inspections and eddy current testing were proposed to manage this degradation mechanism.

Issue:

The staff needs additional information concerning the degradation mechanism and the component/environment to ascertain whether the proposed aging management program is adequate.

Request:

Please provide a description briefly discuss the nature of these components (including their function) and the extent to which they are used throughout the steam generator; a sketch/diagram may be useful. Please discuss the susceptibility of these particular components to thermal aging embrittlement (

Reference:

Letter from C.I. Grimes, NRC, to Douglas J.

Walters, Nuclear Energy Institute, License Renewal Issue No. 98-0030, Thermal Aging Embrittlement of Cast Stainless Steel Components, dated May 19, 2000, ML003717179).

Discuss how visual inspections and eddy current testing will be adequate to ensure any loss of fracture toughness that does occur will be limited such that the component will continue to be able to perform its intended safety function during normal operation, transient, and accident conditions. That is, discuss the possibility that the loss of fracture toughness would render the component incapable of performing its function without the component showing any visual evidence of cracking, deformation, or damage.

ENCLOSURE 2

Discussion: The applicant requested clarification on the staffs request. The applicant requested the staff to identify the applicability of the question and whether there was a need for a sketch or diagram when discussing the steam generator components. The staff agreed to identify the applicability of the question for Byron Unit 1 and Braidwood Unit 1; and after further review, the staff agreed to remove the request for a sketch or diagram. The staff also added eddy currents to the scope of the request as indicated by the underlined portion in the Background and Request sections. All underlined portions indicated additions made to the original DRAI, and the strikethrough indicates a deletion. This question will be sent as a formal RAI titled: RAI 3.1.2.3.4-1.

DRAI 3.0.3-3a Applicability:

Byron and Braidwood

Background:

In a letter dated January 13, 2014, the responses to RAIs 3.0.3-3 and B.2.1.23-1 state that cracking due to stress corrosion cracking is not an aging effect in outdoor air environments for stainless steel and aluminum components that have jacketed insulation.

In regards to potential cracking due to halides in the atmosphere, the responses stated that (a) halide accumulation from the environment is not expected on components that are shielded by jacketed insulation and (b) insulated components located outdoors do not operate at high temperatures where concentration of environmental halides is expected to occur due to evaporation of any present moisture.

The Generic Aging Lessons Learned (GALL) Report aging management program (AMP)

XI.M38, External Surfaces Monitoring of Mechanical Components, recommends visual inspections for leakage to detect cracking on external surfaces that are exposed to an air environment containing halides.

Issue:

The staff recognizes that proper jacketing configuration can be a preventive measure for atmospheric halide intrusion; however, the staff considers a one-time inspection of exposed metal for evidence of cracking as necessary to ensure that the jacketing at Byron and Braidwood is an effective barrier. Also, it is not clear to the staff why the absence of high operating temperatures would prevent moisture from evaporating on an outdoor components surface.

Request:

For insulated stainless steel and aluminum components exposed to outdoor air, provide the technical justification for why exposed metal inspections for cracking are not necessary to confirm the effectiveness of the insulation jacketing in preventing halide intrusion. Alternatively, propose a baseline exposed metal inspection for cracking that may be used to validate the subsequent use of insulation-only inspections and revise the associated AMR items to include cracking as an applicable aging effect.

Discussion: The applicant requested clarification on the staffs request. Minor editorial comments were addressed. In the Background section, the staff decided to specify visual inspections, as indicated by the underlined portion in the last paragraph. It was noted by the applicant that the GALL Report AMP was improperly listed as XI.M38; it will be correctly labeled: XI.M36. The staff decided to include an additional discussion regarding potential leakage of nonwater-filled piping and piping components and agreed to revise the request per the following:

Request:

For insulated stainless steel and aluminum piping and piping components exposed to outdoor air, provide the technical justification for why insulation does not need to be removed to conduct visual inspections to detect cracking in order to confirm the effectiveness of the insulation jacketing in preventing halide intrusion. Alternatively, propose to remove insulation during a baseline inspection for cracking that may be used to validate the subsequent use of insulation-only inspections and revise the associated AMR items to include cracking as an applicable aging effect. For nonwater-filled piping and piping components, state how potential leakage will be identified.

This question will be sent as a formal RAI titled: RAI 3.0.3-3a.