ML14133A687

Summary of Telephone Conference Call Held on May 6, 2014, Between the U.S. Nuclear Regulatory Commission and Exelon Generation Company, LLC Concerning Draft Request for Additional Information, Set 25, Pertaining the Byron Station and Braidw

ML14133A687
Person / Time
Site:	Byron, Braidwood
Issue date:	05/19/2014
From:	Robinson L License Renewal Projects Branch 1
To:
Robinson L, 415-8411
References
TAC MF1879, TAC MF1880, TAC MF1881, TAC MF1882
Download: ML14133A687 (6)

Text

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

SUMMARY

OF TELEPHONE CONFERENCE CALL HELD ON MAY 6, 2014, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION COMPANY, LLC CONCERNING DRAFT REQUEST FOR ADDITIONAL INFORMATION, SET 25, PERTAINING TO THE BYRON STATION AND BRAIDWOOD STATION, LICENSE RENEWAL APPLICATION (TAC NOS. MF1879, MF1880, MF1881, AND 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 May 6, 2014, to discuss and clarify the staffs draft request for additional information (DRAI),

Set 25, concerning the Byron Station, Units 1 and 2, and the Braidwood Station, Units 1 and 2, license renewal application. The staff also discussed its concern with the applicants responses to previous staff request for additional information (RAI) (ADAMS Accession Number:

ML14063A495) regarding the 10-year frequency for visual inspections for evidence of corrosive environments associated with high strength structural bolting in containment. 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

ML14133A687 *concurred via email OFFICE LA:DLR PM: RPB1:DLR BC:RPB1:DLR PM:RPB1:DLR NAME IKing LRobinson YDiazSanabria LRobinson DATE 5/14/14 5/15/14 5/15/14 5/19/14

SUMMARY

OF TELEPHONE CONFERENCE CALL HELD ON MAY 6, 2014, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION COMPANY, LLC CONCERNING DRAFT REQUEST FOR ADDITIONAL INFORMATION, SET 25, PERTAINING TO THE BYRON STATION AND BRAIDWOOD STATION, LICENSE RENEWAL APPLICATION (TAC NOS. MF1879, MF1880, MF1881, AND MF1882)

DISTRIBUTION EMAIL:

PUBLIC RidsNrrDlr Resource RidsNrrDlrRpb1 Resource RidsNrrDlrRarb Resource RidsNrrDlrRasb 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 May 6, 2014 PARTICIPANTS AFFILIATIONS Lindsay Robinson U.S. Nuclear Regulatory Commission (NRC)

Michael Marshall NRC William Holston NRC James Medoff NRC Angie Buford NRC John Hufnagel Exelon Generating Company, LLC (Exelon)

Don Warfel Exelon Al Fulvio Exelon Jim Annett Exelon Paul Cervenka Exelon Casey Muggleston Exelon ENCLOSURE 1

DRAFT REQUEST FOR ADDITIONAL INFORMATION BYRON STATION, UNITS 1 AND 2, AND BRAIDWOOD STATION, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION May 6, 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 May 6, 2014, to discuss and clarify the following draft request for additional information (DRAI),

Set 25, concerning the Byron Station, Units 1 and 2, and the Braidwood Station, Units 1 and 2, license renewal application (LRA).

DRAI 3.5.2.3.15-1 Applicability:

Byron Station (Byron) and Braidwood Station (Braidwood), all units

Background:

License renewal application (LRA) Table 3.5.2-15, Structural Commodity Group: Structural Commodity Group Summary of Aging Management Evaluation, includes two plant-specific age management review (AMR) items: lead (Pb) penetrations seals that are exposed to (1) indoor uncontrolled air and (2) indoor air with borated water leakage. The LRA identifies that there are no aging effects that are applicable to the exposure of these seals to these environments. The AMR items cite generic Note J, which states that neither the component nor the materials and environment are evaluated in the Generic Aging Lessons Learned (GALL) Report. The AMR items also a reference a plant-specific Note 9 on the AMR table, which states:

This material and environment applies to the lead wool used for packing penetrations for radiation shielding. Operating experience has shown the air-indoor uncontrolled and air with borated water leakage environments to contain insignificant quantities of moisture, humidity, condensation, and contaminants during normal operation. Therefore, there are no aging effects associated with the lead material in the normal dry, air - indoor uncontrolled and air with borated water leakage environments.

Per 10 CFR 54.21(a)(3), the licensee is required to demonstrate that the effects of aging will be adequately managed during the period of extended operation for each structure or component that is scoped in for license renewal in accordance with the requirements in 10 CFR 54.4 and has been screened in for an AMR in accordance with the requirement in 10 CFR 54.21(a)(1).

Since the applicant has identified air with borated water leakage environment as an applicable environment for these seal materials, the applicant must evaluate the seal materials applicable aging effects under exposure to the both containment air environment and postulated sources of borated water.

Issue:

The applicable plant-specific AMR item in LRA Table 3.5.2-15 identifies the indoor air with borated water leakage environment as an applicable environment for these ENCLOSURE 2

containment penetration seals. However, plant-specific Note 9 for the AMR item only addressed the impacts of moisture, humidity, condensation and impurity contaminants in the containment air would have on the lead (Pb) seal materials (i.e., lead packing wool). The plant-specific Note for the AMR item did not address the impact that borated water would have on these seal materials if the borated water were to leak onto these penetration seal materials. It is not clear to the staff whether the aging effect of loss of material due to boric acid corrosion would not be considered if the lead packing wool is exposed to an indoor air with borated water leakage environment Request:

Provide the technical basis as to why loss of material due to boric acid corrosion of the lead packing wool used in the penetration seals has not been identified as an aging effect requiring management for the applicable AMR item in LRA Table 3.5.2-15. Amend the application, accordingly, if it is determined that loss of material due to postulated boric acid corrosion is an applicable aging effect requiring management for these penetration seals.

Discussion: The applicant requested clarity on the staffs concern. No edits were proposed.

This question will be sent as part of the formal request titled: RAI 3.5.2.3.15-1.