ML111330624
| ML111330624 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood  |
| Issue date: | 06/09/2011 |
| From: | Nicholas Difrancesco Plant Licensing Branch III |
| To: | |
| DiFrancesco N, NRR/DORL/LPL3-2, 415-1115 | |
| Shared Package | |
| ML111330636 | List: |
| References | |
| TAC ME4815, TAC ME4816, TAC ME4817, TAC ME4818 | |
| Download: ML111330624 (11) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 June 9, 2011 LICENSEE:
Exelon Generation Company, LLC FACILITY:
Byron Station, Unit Nos. 1 and 2, (Byron) and Braidwood Station, Units 1 and 2 (Braidwood)
SUBJECT:
SUMMARY
OF MAY 18, 2011, MEETING WITH EXELON GENERATION COMPANY, LLC, PRE-APPLICATION DISCUSSION ON FORTHCOMING BYRON AND BRAIDWOOD MEASUREMENT UNCERTAINTY RECAPTURE (MUR) LICENSE AMENDMENT REQUEST (LAR) (TAC NOS. ME4815, ME4816, ME4817, AND ME4818)
On May 18, 2011, a Category 1 public meeting teleconference was held between the U.S.
Nuclear Regulatory Commission (NRC) and representatives of Exelon Generation Company, LLC (EGC, the licensee). The purpose of the meeting was to discuss project updates to a forecasted June 2011, LAR submittal for a MUR power uprate of approximately 1.63 percent to 3645 megawatts thermal. A prior pre-application meeting was held at NRC headquarters November 4, 2010, as discussed in a meeting summary dated November 29, 2010 (Agencywide Document Access and Management System (ADAMS) Accession No. ML103260212).
The licensee's presentation (see Enclosure 2) summarized the regulatory and technical bases for the planned application, as well as key analyses and potential modifications planned for inclusion in the planned application. Key discussion points between the NRC staff and the licensee include:
- 1. The licensee plans to submit a MUR LAR with a 12-month review schedule. The MUR request will include additional analyses in the areas of margin-to-overfill (MTO) analyses for the steam generator tube rupture (SGTR) accident, and VIPRE code correlation updates to enhance departure from nucleate boiling (DNB) analysis margins (see Slide 5).
The licensee and NRC staff discussed Regulatory Issue Summary (RIS) 2002-03, "Guidance on the Content of Measurement Uncertainty Recapture Power Uprate Applications," in the filling of MUR requests. RIS 2002-03 contains templates for the content of MUR applications and advised licensees that MUR reviews would be completed in 6 - 8 months for typical applications and 1 - 2 years for MUR applications which contained other requests.
- 2. The NRC staff provided feedback in several technical areas based on the proposed request and recent NRC experience with similar reviews. These include:
- a. NRC staff reiterated the need for EGC to address the specific limitations and conditions associated with NRC approval of any Topical Reports utilized in any new or updated analysis methodologies (e.g., VIPRE).
-2
- b. Ensure justification for duration of revised and new operator manual actions is provided (e.g., SGTR MTO analysis). The justification should include demonstration of timed operator actions and key tasks. The staff noted similar reviews where NRC has conducted site audits to verify analysis assumptions.
- c. Ensure that revised dose analysis inputs and assumptions are well documented within the LAR.
- d. Ensure licensing basis review of the planned steam generator power operated relief valve power supply modifications is conducted. Licensee should evaluate how changes to the electric power supply affect the facilities Updated Final Safety Analysis Report and ensure these are reflected in the MUR LAR as appropriate. NRC staff suggested that the licensee explain the interface between the MUR LAR and the EGC's response to the NRC verification inspection report letter containing several regulatory commitments dated March 2, 2011 (ADAMS Accession No. ML110620089).
- 3. The NRC staff discussed several best practices when developing power uprate licensing submittals:
- a. The NRC staff recommended that the licensee identify all related/supporting Title 10 of the Code of Federal Regulations (10 CFR) Section 50.59 reviews prior to submission of the LAR to prevent unplanned changes to the NRC staff review.
- b. The NRC staff recommended that the licensee seek prior review and approval of complex analyses (e.g., best-estimate loss-of-coolant accident [as approved in December 2010, for Braidwood and Byron], DNB analysis). This best practice minimizes the potential of NRC staff questions, resulting in reanalysis being performed during NRC staff review. When similar situations have occurred, applications are often delayed or withdrawn.
- c. The NRC regulations at 10 CFR Part 50, Appendix B, Criterion XVI, require that licensees complete corrective actions promptly. The NRC staff noted that disposition of present facility corrective actions are most effectively addressed in NRC reviews independent of a LAR for power uprate.
- d. The NRC staff discussed recent power uprate reviews where licensees had requested power uprates which included multiple dependent safety analyses which complicated NRC staff reviews {e.g., Point Beach extended power uprate LAR, approved on May 3, 2011 (ADAMS Accession No. ML111170513).
- 4. The licensee inquired into the NRC staff concerns associated with the planned Braidwood and Byron MUR application. The NRC staff noted that NRR resources assume a MUR application typically requires 6 months to review (following NRC staff acceptance of the application). Additional analyses make the proposed MUR request more complex, requiring additional resources, and introduces uncertainty into review templates and schedules.
-3 The NRC staff noted that no regulatory decisions were made during this meeting. The NRC staff will perform an acceptance review of the licensee's application in accordance with NRC regulation and agency procedures when received.
No members of the public were in attendance. No public meeting feedback forms were received.
Please direct any inquiries to me at 301-415-1115, or nicholas.difrancesco@nrc.gov.
Sincerely, Nicholas J. DiFrancesco, Project Manager Plant Licensing Branch 111-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. STN-456, STN-457, STN 50-454, and STN 50-455
Enclosures:
- 1. List of Attendees
- 2. Licensee Handout cc w/encl: Distribution via ListServ
LIST OF ATTENDEES MAY 18, 2011, PUBLIC MEETING TElECONFERNCE WITH EXElON GENERATION COMPANY, llC, PRE-APPLICATION DISCUSSION ON FORTHCOMING BYRON AND BRAIDWOOD MEASUREMENT UNCERTAINTY RECAPTURE LICENSE AMENDMENT REQUEST Name Affiliation J. lehning NRC/NRR J. Zimmerman NRC/NRR S.Sun NRC/NRR T. Alexion NRC/NRR S. Gardocki NRC/NRR T. Mossman NRC/NRR D. Duvigneaud NRC/NRR T. Tate NRC/NRR N. DiFrancesco NRC/NRR E. Brown NRC/NRR J. Purciarello NRC/NRR J. Rommel Exelon D. Benyak Exelon K. Borton Exelon J. Wilson Exelon L. Dworakowski Exelon J. Bauer Exelon D. Baran Exelon A. Wong Exelon J. DelaRosa Exelon L. Schofield Exelon D. Spitzer Exelon
LICENSEE HANDOUT MAY 18. 2011. PUBLIC MEETING WITH EXELON GENERATION COMPANY. LLC, PRE-APPLICATION DISCUSSION ON FORTHCOMING BYRON AND BRAIDWOOD MEASUREMENT UNCERTAINTY RECAPTURE LICENSE AMENDMENT REQUEST
Exelon~
Nuclear
Introductions
Byron and Braidwood Stations NRC Pre-Application Public Meeting Analyses Supporting Measurement Uncertainty R.ecapture (MUR.) Power Uprate May 18, 2011 Exelon Participants
-/ John Rommel - Engineering Director, Power Uprate
-/ Darin Benyak - Licensing Director, Corporate
-/ Kevin Borton - Licensing Manager, Power Uprate
-/ Jeff Wilson - Manager of Projects, Power Uprate
-/ Joe Bauer - Principal Regulatory Engineer, Power Uprate
-/ Dave Baran - lead Engineer, Power Uprate
-/ Annie Wong - lead Analyst, Power Uprate
-/ Jessica DelaRosa - lead Dose Analyst, Power Uprate
-/ Lisa Schofield - Sr Regulatory Engineer, Licensing
-/ lydia Dworakowski - Braidwood, Regulatory Assurance
-/ Doug Spitzer - Byron Station, Regulatory Assurance Exelen.
Nuclear
PURPOSE:
,./ Review the Basis for the Exelon Forthcoming MUR Application AGENDA:
,./ Summary of Nov 4, 2010 Pre-application Meeting
- LAR Development and Objective
- Key Analyses
- Modifications
- Nov 4 Meeting Conclusion
- Submittal and Power Ascension Schedule
,./ Confirm Need for Related VIPRE and SGTR/MTO Analyses
,./ NRC Feedback Exel....,n.
Nuclear Summa of Nov 2010 Meetl MUR LAR Development and Objective
./ Combined MUR amendment request for Byron and Braidwood Stations Units 1 and 2 to increase power approximately 1.63%
(3586.6 Mvvth to 3645 Mvvth)
./ 10 CFR 50 Appendix K, ECCS Evaluation Models
./ Regulatory Issue Summary (RIS) 2002-03 "Guidance on the Content of Measurement Uncertainty Recapture Power Uprate Applications"
./ Cameron Check-Plus Leading Edge Flow Meter (LEFM) L TR (ER-80P, ER-157P)
./ NRC LlC-109, "Acceptance Review Procedures"
./ LAR will be formatted similar to the North Anna and Prairie Island MUR submittals addressing previous NRC MUR Industry Requests for Additional Information (RAI)
Exel....,n.
Nuclear
of Nov 2010 M Key Analyses (supporting MUR) v" VIPRE Computer Code; ABB-NV and WLOP Correlations
- These NRC-approved codes are necessary to demonstrate adequate DNB margin under MUR conditions (NOTE: inadequate DNB margin results under MUR conditions using the current ONB correlations)
VIPRE is a thermal-hydraulic code used by Westinghouse for DNBR analysis ABB-NV is a critical heat !lux correlation applicable to the non-mixing vane grid region WLOP is a critical heat !lux correlation for low pressure applications v" Revised Steam Generator Tube Rupture (SGTR) Analysis
- Westinghouse re-analysis Is necessary and the associated core heat transfer coefficients are power dependent which will result in a reduction in MTO of approximately 20 ft3 at MUR conditions
- Westinghouse analysis uses an NRC-approved method (WCAP 10698-P-A and Supplement 1)
Exelon.
Nuclear Sum...;IIlrv of Nov 2010 Modifications
./ Modifications Supporting MUR
- HP Turbine Modifications
- BOP Modifications
- LEFM Modification Initial calibration at Alden Research Laboratory using site specific piping model Final commissioning on site after installation confirms system performance NRC criteria for utilizing LEFM technology will be addressed in the LAR LEFM installation
- SGTRIMTO-Related Modifications Add AFWvalve Instrument air accumulators (Unit 1 and Unit 2)
Replace SG PORV trim to increase steam !low (Unit 1 only)
Add Uninterruptible power supplies for SG PORVs Install High Head Safety Injection system manual isolation valves Exelon.
Nuclear
Current Schedule Submittal and Power Ascension Schedule
./ LAR Submittal Target Date: June 2011
./ LAR Approval Target Date: June 2012
./ LEFM Installation and Power Ascension Schedule Site/Unit Install LEEM Power Ascension BYR U1 03111 Complete 11/12 (post outage)
BYR U2 09111 09112 (mid-cycle)
BRWU1 04112 11112 (mid-cycle)
BRWU2 04111 Complete 12112 (post outage)
Exelon.
Nuclear of Nov 2010 Meetl Meeting Conclusion
,/ Conclusions taken from NRC Meeting Summary LeHer. dated November 29.2010 The licenaee's presentation (see Enclosure 2) 8UI'IImarized the regulatory and technical bases for the planned application. as well as key analyses and lXlIentiai modlfications planned for inclusion in the planned application. Key dlacussion points between the NRC staff and the licensee:
- 1. The licensee plans to provide revised dose and marglMo-overfili analyses for the steam generator tube rupture accident (see Slide 9). The NRC stated that the review of these analyses could not be perfonned within the target 6-month review schedule for a MUR, and would Ukely require 12 months. The Neen... PlOted that they anticipate a 12-montll review.
- 2. The NRC staff reinforced the need for the licensee to eddress the specific limitalionl and conditions YS. approved Topical Repor1ll for any new or updated analysis methodologies.
- 3. The NRC staff noted that its approval of the prerequisite ASTRUMIBELOCA amendment (see Slide 7) would fikely ocx:ur before the April 2011, MUR apprlCation submittal.
Exelon.
Nuclear
Need for VIPRE and SGTRIMTO Required for MUR Operations
-/ VIPRE computer Code; ABB-NV and WLOP Correlations
-/ Steam Generator Tube Rupture (SGTR) Revised Analysis
- Westinghouse re-analysis is necessarY and the associated core heat transfer coefficients are power dependent which result in a reduction in MTO at MUR conditions
-/ Exelon will be requesting a MUR LAR 12 month approval Exelen.
Nuclear Discussion Feedback Exelen.
Nuclear
-3 The NRC staff noted that no regulatory decisions were made during this meeting. The NRC staff will perform an acceptance review of the licensee's application in accordance with NRC regulation and agency procedures when received.
No members of the public were in attendance. No public meeting feedback forms were received.
Please direct any inquiries to me at 301-415-1115, or nicholas.difrancesco@nrc.gov.
Sincerely, IRA!
Nicholas J. DiFrancesco, Project Manager Plant Licensing Branch 111-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. STN-456, STN-457, STN 50-454, and STN 50-455
Enclosures:
- 1. List of Attendees
- 2. Licensee Handout cc w/encl: Distribution via ListServ DISTRIBUTION:
PUBLIC AUlses, NRR BParks, NRR LPL3-2 RtF GCasto, NRR T Alexion. NRR Rids AcrsAcnw_MailCTR Resource UShoop, NRR SGardocki, NRR RidsNrrAdro Resource RTaylor, NRR TMossman, NRR RidsNrrDorl Resource AMendiola, NRR AAttard, NRR RidsNrrDorlLpl3-2 Resource TTate. NRR DDuvigneaud, NRR RidsNrrPMByron Resource NDiFrancesco. NRR RAlvarado, NRR RidsNrrPMBraidwood Resource GWilson. NRR AObodoako. NRR RidsNrrLASRohrer Resource SSun. NRR CTucci, NRR RidsOgcRP Resource EBrown, NRR BBartlet, Rill DMerzke, EDO R-III PChung NRR JBenjamin, Rill RidsRgn3MailCenter Resource LBenton, NRR VMitlyng, OPA R-III JPurciarello, NRR Package Accession No. ML111330636 Meeting Notice Accession No. ML111090650 Meef109 SA' N ML111330624 NRC-001 ummary ccesslon o.
OFFICE DORULPL3-2!PM DORULPL3-2/LA DORULPL3-21BC DORULPL3-21PM NAME NDiFrancesco SRohrer JZimmerrnan NDiFrancesco DATE 6/08/11 6/08/11 6/8111 6/9/11 OFFICIAL RECORD COpy