ML15159A900

Telephone Conference Call Held on May 20, 2015, Between the U.S. Nuclear Regulatory Commission and Exelon Generation Co., LLC, Requests for Additional Information, Set 3 Pertaining to the LaSalle County Station License Renewal Application (

ML15159A900
Person / Time
Site:	LaSalle
Issue date:	07/06/2015
From:	Mitchell J S License Renewal Projects Branch 1
To:	Exelon Generation Co
Mitchell J, NRR/DLR, 415-3019
References
DLR-15-0294, TAC MF5346, TAC MF5347
Download: ML15159A900 (11)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 July 6, 2015 LICENSEE: Exelon Generation Co., LLC FACILITY: LaSalle County Station, Units 1 and 2

SUBJECT:

SUMMARY OF TELEPHONE CONFERENCE CALL HELD ON MAY 20, 2015, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION CO., LLC, CONCERNING REQUESTS FOR ADDITIONAL INFORMATION, SET 3 PERTAINING TO THE LASALLE COUNTY STATION LICENSE RENEWAL APPLICATION (TAC NOS. MF5347 AND MF5346)

The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Exelon Generation Co., LLC (Exelon or the applicant) held a telephone conference call on May 20, 2015, to discuss and clarify the staff's draft requests for additional information (DRAIs) provided in Enclosure 2 concerning the LaSalle County Station, Units 1 and 2, license renewal application. The telephone conference call was useful in clarifying the intent of the staff's DRAIs.

Enclosure

1 provides a listing of the participants and Enclosure 2 contains 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. Sincerely,

/RA/ Jeffrey S. Mitchell, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374

Enclosures:

1. List of Participants

2. Summary of Telephone Conference Call cc: Listserv July 6, 2015 LICENSEE: Exelon Generation Co., LLC FACILITY: LaSalle County Station, Units 1 and 2

SUBJECT:

SUMMARY OF TELEPHONE CONFERENCE CALL HELD ON MAY 20, 2015, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION CO., LLC, CONCERNING REQUESTS FOR ADDITIONAL INFORMATION, SET 3 PERTAINING TO THE LASALLE COUNTY STATION LICENSE RENEWAL APPLICATION (TAC NOS. MF5347 AND MF5346)

The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Exelon Generation Co., LLC (Exelon or the applicant) held a telephone conference call on May 20, 2015, to discuss and clarify the staff's draft requests for additional information (DRAIs) provided in Enclosure 2 concerning the LaSalle County Station, Units 1 and 2, license renewal application. The telephone conference call was useful in clarifying the intent of the staff's DRAIs. Enclosure 1 provides a listing of the participants and Enclosure 2 contains 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.

Sincerely, /RA/ Jeffrey S. Mitchell, Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374 Enclosures: 1. List of Participants

2. Summary of Telephone Conference Call

cc: Listserv DISTRIBUTION: See next page ADAMS Accession Number: ML15159A900 *Concurred via e-mail OFFICE LA:DLR* PM:RPB1:DLR PM:RPB1:DLR BC:RPB1:DLR PM:RPB1:DLR NAME SWoods JMitchell RPlasse YDiaz-Sanabria JMitchell DATE 6/16/15 6/19/15 6/19/15 6/25/15 7/6/15 OFFICIAL RECORD COPY Memo to Exelon Generation Co. from J. Mitchell dated July 6, 2015 SUBJECT: SUMMARY OF TELEPHONE CONFERENCE CALL HELD ON MAY 20, 2015, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND EXELON GENERATION CO., LLC, CONCERNING REQUESTS FOR ADDITIONAL INFORMATION, SET 3 PERTAINING TO THE LASALLE COUNTY STATION LICENSE RENEWAL APPLICATION (TAC NOS. MF5347 AND MF5346) DISTRIBUTION: E-MAIL: PUBLIC RidsNrrDlr Resource RidsNrrDlrRpb1 Resource RidsNrrDlrRpb2 Resource RidsNrrDlrRerb Resource RidsNrrDlrRarb Resource RidsNrrDlrRasb Resource RidsNrrDlrRsrg Resource RidsNrrPMLaSalle Resource ---------------

J. Mitchell R. Plasse D. Drucker B. Wittick J. Wachutka, OGC D. McIntyre, OPA M. Kunowski, RIII V. Mitlyng, RIII P. Chandrathil, RIII H. Logaras, RIII C. Lipa, RIII S. Sheldon, RIII R. Ruiz, RIII J. Robbins, RIII ENCLOSURE 1 TELEPHONE CONFERENCE CALL LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION LIST OF PARTICIPANTS MAY 20, 2015 PARTICIPANTS AFFILIATION Jeffrey Mitchell U.S. Nuclear Regulatory Commission (NRC)

Mark Yoo NRC Catherine Nolan NRC Bill Holston NRC Naeem Iqbal NRC John Hufnagel Exelon Generation Co., LLC (Exelon)

Deb Spamer Exelon Wayne Choromanski Exelon Mark Miller Exelon Jim Jordan Exelon Paul Weyhmuller Exelon

ENCLOSURE 2 SUMMARY OF TELEPHONE CONFERENCE CALL LASALLE COUNTY STATION, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION MAY 20, 2015 The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Exelon Generation Co., LLC (Exelon or the applicant) held a telephone conference call on May 20, 2015, to discuss and clarify the following draft requests for additional information (DRAIs) concerning the LaSalle County Station (LSCS), Units 1 and 2 license renewal application (LRA). DRAI 2.3.3.12-1: Background: For LaSalle County Station, Units 1 and 2, the staff reviewed the LRA; drawings; UFSAR, Section 9.5.1, Fire Protection System," and Fire Protection Report (FPR) which describe the fire protection program at LSCS Units 1 and 2, and how it complies with the requirements of 10 CFR 50.48, "Fire protection," and the guidelines of Appendix A to Branch Technical Position (BTP) Auxiliary Power System (ASP) 9.5-1. Issue: The following boundary drawing shows the following fire protection systems/components as not within the scope of license renewal (i.e., not colored in green): LRA Drawing Systems/Components Location LR-LAS-M-78, Sheet 1 Flame arrestors F4 LR-LAS-M-78, Sheet 1 CO2 fire suppression system components C4 and C5 Request: Verify whether the fire protection systems/components listed above are within the scope of license renewal in accordance with 10 CFR 54.4(a) and whether they are subject to an aging management review (AMR) in accordance with 10 CFR 54.21(a)(1). If they are not within the scope of license renewal and are not subject to an AMR, the staff requests that the applicant provide justification for the exclusion. Teleconference Summary: The staff clarified a question regarding the location of the flame arrestors in question and confirmed the specific CO2 system components in question. The staff will correct the drawing locations to be grids E4 and E5, instead of F4, in the final RAI letter.

- 2 - DRAI 2.3.3.12-2: Background: LRA Section 2.3.3.12, "Fire Protection System," indicates that fire pumps take suction from the service water tunnel and supply water to the fire main ring header and yard fire hydrants. Issue: It is not clear to the NRC staff if the service water tunnel has been appropriately identified as a component type within the scope of license renewal and subject to an AMR. Request: Verify whether the service water tunnel is within the scope of license renewal in accordance with 10 CFR 54.4(a) and whether the service water tunnel is subject to an AMR in accordance with 10 CFR 54.21(a)(1). If the service water tunnel is not within the scope of license renewal and is subject to an AMR, the staff requests that the applicant provide justification for the exclusion. Teleconference Summary: The applicant demonstrated that the information requested in this DRAI is provided in LRA Section 2.4.5. The staff determined the information in Section 2.4.5 adequately addresses this DRAI, and this DRAI will be deleted from the final RAI letter. DRAI 2.3.3.12-4: Background: LRA Section 2.3.3.12, "Fire Protection System," indicates the drains from fire water system components and areas protected by the fire water system which are identified with the Plant Drainage System. LRA Section 2.3.3.16, "Plant Drainage System," indicates that the portions of the floor drain systems in the Auxiliary Building, Diesel Generator Building, and Turbine Building are credited for the removal of fire water from areas containing safe-shutdown equipment and are in scope for Fire Safe Shutdown. Further, Section 2.3.3.16 indicates that the portions of the floor drain system in the Diesel Generator Building are credited to prevent the accumulation of oil in areas containing safe-shutdown equipment and are in scope for Fire Safe Shutdown. Table 2.3.3-16, "Components Subject to Aging Management Review," of the LRA does not include fire water and oil floor drains as a component type subject to an AMR. Issue: It is not clear to the NRC staff if the Auxiliary Building, Diesel Generator Building, and Turbine Building fire water floor drains and Diesel Generator Building floor drains credited to prevent oil accumulation have been appropriately identified as a component type subject to an AMR.

- 3 - Request: Verify whether the fire water floor drains and Diesel Generator Building oil floor drains are subject to an AMR in accordance with 10 CFR 54.21(a)(1). If they are not subject to an AMR, the staff requests that the applicant provide justification for the exclusion. Teleconference Summary: The applicant did not have any questions on this DRAI. This DRAI will be re-numbered in the final RAI set as RAI 2.3.3.12-3, due to the deletion of DRAI 2.3.3.12-2 (DRAI 2.3.3.12-3, not discussed during this call, will be re-numbered to RAI 2.3.3.12-2). DRAI B.2.1.9-1: Background: LRA Section B.2.1.9 describes the following operating experience related to jet pumps that are included in the scope of the applicant's Boiling Water Reactor (BWR) Vessel Internals program. In 2004, the applicant visually inspected all the Unit 1 jet pump riser brace RS-8 and RS-9 welds. The applicant noted indications at the RS-9 welds on the jet pump 5 and 6 sections of the jet pump 5/6 riser brace, and noted one indication on the jet pump 9 side of the jet pump 9/10 riser brace. As a result, the applicant initiated a corrective action program issue report and installed a clamp at the slip joint on all 20 jet pumps. Section 4.3.4 of BWRVIP-41 indicates that flow-induced vibration caused by leakage at jet pump slip joints has been known to occur and cause damage to reactor internals. The following reference also indicates that, in addition to slip joint leakage, flow pressure pulsations from recirculation pumps at vane passing frequency (also called pump resonance) and flow-induced vibration from turbulent flow are potential causes for jet pump degradation.

• Jet Pump Degradation Management, EPRI-NRC Technical Exchange Meeting Presentation, May 25-26, 2010 (ADAMS Accession Number ML101590703) In addition, Section 2.3.8 and its subsections of BWRVIP-41 describe degradation assessment and recommended inspections for jet pump restrainer bracket assembly. These sections indicate that excessive wear on the wedge bearing surface and misalignment has been observed in the industry operating experience. These sections also indicate that excessive wear at the wedge bearing surface is an indication of substantial vibration and may indicate that other jet pump components may be damaged. Issue: The LRA does not clearly address whether the applicant's program resolved the concern about jet pump vibration resulting from slip joint leakage flow instability, pump resonance or turbulent flow. The LRA does not address assessment of plant-specific operating experience regarding jet pump vibration and loss of material due to wear of jet pump wedges and restrainer brackets at their interfaces. The staff needs additional information to determine whether the program

- 4 - needs to be enhanced with additional aging management activities and inspections based on adequate assessment of operating experience. Request: 1. Discuss how the applicant's program resolved the concern about jet pump vibration for Units 1 and 2. 2. Provide the assessment of plant-specific operating experience regarding jet pump vibration and loss of material due to wear of jet pump wedges and restrainer brackets at their interfaces. As part of the response, clarify why a program enhancement is not necessary for adequate management of jet pump degradation (such as fatigue and wear) due to jet pump vibration. Teleconference Summary: The applicant did not have questions on this DRAI.

DRAI B.2.1.17-2: Background: LRA Section B.2.1.17 states an exception (Exception No. 2) to performing charcoal filter deluge testing. The LRA exception states that visual inspections will be performed on one of the 11 charcoal filter deluge systems every five years. AMP XI.M27, as modified by LR-ISG-2012-02, "Aging Management of Internal Surfaces, Fire Water Systems, Atmospheric Storage Tanks, and Corrosion Under Insulation," states that deluge valves should be trip-tested annually at full flow or tested with air to ensure nozzles are not obstructed. LR-ISG-2012-02 also states that tests may be performed during plant shutdowns on a refuel cycle interval. Issue: During the audit, the staff noted that the proposed visual inspections of the charcoal filter system will only be conducted on the stainless steel portion of the piping downstream of a normally closed isolation valve. The upstream carbon steel piping will not be inspected. Deluge testing, as recommended by AMP XI.M27, Table 4a, "Fire Water System Inspection and Testing Recommendations," would demonstrate that both the stainless steel and carbon steel portions are not experiencing potential flow blockage. It is unclear to the staff how the use of visual examinations of the stainless steel portions of the deluge system piping will provide reasonable assurance that flow blockage is not occurring in the upstream carbon steel piping. A basis was not provided for conducting the visual inspections every 5 years when Table 4a recommends an inspection interval of no longer than a refueling outage interval. Request: Justify the use of performing visual examinations in lieu of full flow or air tests for the charcoal filter deluge testing. In addition, provide the basis for the 5-year frequency of the aforementioned testing.

- 5 - Teleconference Summary: The applicant did not have questions on this DRAI. DRAI B.2.1.17-3: Background: The "acceptance criteria" program element of AMP XI.M27, as amended by LR-ISG-2012-02 states, "[if] the presence of sufficient foreign organic or inorganic material to obstruct pipe or sprinklers is detected during pipe inspections, the material is removed and its source is determined and corrected." Issue: During the audit, the staff reviewed corrective action process procedure, PI-AA-230, to determine if the procedure included sufficient specificity to be consistent with the "acceptance criteria" program element of AMP XI.M27. It is unclear to the staff that foreign organic or inorganic material sufficient to obstruct piping or sprinklers will be removed and its source determined and corrected if it is detected during pipe inspections. Therefore, the staff cannot conclude that there is reasonable assurance that flow blockage due to foreign organic or inorganic material will not occur during the period of extended operation. Request: Justify how the Fire Water System Program "acceptance criteria" program element is sufficient to provide reasonable assurance that the intended function of fire water system piping will be met during the period of extended operation. Teleconference Summary: The applicant clarified the title and document number of corrective action process procedure PI-AA-230. The staff will correct the title and document number in the final RAI letter. The applicant did not have questions on this DRAI. DRAI B.2.1.17-4: Background: Procedure LOS-FP-SR3, "Fire Protection Water Spray/Sprinkler Systems Headers, Nozzles and Sprinkler Integrity Inspection," includes criteria for visually inspecting sprinkler systems for corrosion. The frequency of inspecting sprinklers per the Technical Requirements Manual (TRM), Section 3.7.k, is every 24 months. AMP XI.M27, Table 4a, recommends that annual visual inspections for leakage, loss of fluid in the glass bulbs, and loading be conducted.

- 6 - Issue: LOS-FP-SR3 does not include inspections for leakage, loss of fluid in the glass bulbs, and loading. No basis was provided for conducting the sprinkler inspections every 2 years in lieu of the recommended annual inspections in AMP XI.M27. Request Justify the exclusion of the visual inspection criteria for leakage, loss of fluid in the glass bulbs, and loading from sprinkler inspections. Also, justify the frequency of inspections for the sprinklers. Teleconference Summary: The applicant did not have questions on this DRAI. DRAI B.2.1.17-5: Background: National Fire Protection Association (NFPA) 25, "Standard for the Inspection, Testing, and Maintenance of Water Based Fire Protection Systems," Section 13.2.5.3 states, "[w]hen there is a 10 percent reduction in full flow pressure when compared to the original acceptance test or previously performed tests, the cause of the reduction shall be identified and corrected if necessary." LOS-FP-A3, states, "[if] any of the recorded pressure drops vary from the previous test by greater than 5 psi, we [system engineering] will generate an IR [Issue Report] if the data varies substantially." Issue: It is not clear to the staff how the stated testing parameters are consistent with NFPA 25, as referenced by AMP XI.M27. Request: Justify how performing analysis and trending on changes in pressure will provide reasonable assurance that the main drain test will be consistent with NFPA 25, Section 13.2.5.3, as referenced by AMP XI.M27. Teleconference Summary: The staff clarified that the NFPA 25 section being referenced should be Section 13.2.5.2, instead of Section 13.2.5.3. The staff will correct the section number in the final RAI letter. The applicant did not have further questions on this DRAI.

- 7 - DRAI B.2.1.17-6: Background: During a search of the operating experience database, there were many issue reports generated on the fire water protection system regarding degradation of flow characteristics (i.e., C factor) in the underground fire loop. The fire protection system is a raw water system. Plant drawing LR-LAS-M-775, Sheet 1, provided during the audit, shows the fire protection yard loop with annotated flow testing node points. Data was provided to the staff on the C factor from years 2006 through 2014. The piping segment from the diesel driven fire pump to node 515 shows a significant degrading trend. Issue: It is unclear to the staff how the piping segment from the diesel driven fire pump to node 515 will be able to perform its intended function during the period of extended operation due to its significant degrading trend. Request: Justify how the degrading section of the fire protection yard loop from the diesel driven fire pump to node 515 will be able to perform its intended function during the period of extended operation with its current significant degrading trend. Teleconference Summary: The applicant did not have questions on this DRAI.