ML17297A044
| ML17297A044 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 10/26/2017 |
| From: | Farideh Saba Plant Licensing Branch II |
| To: | Tennessee Valley Authority |
| Saba F, NRR/DORL/LPLII-2, 415-1447 | |
| References | |
| CAC MG0225, EPID L-2017-LRM-0018 | |
| Download: ML17297A044 (6) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 October 26, 2017 APPLICANT: Tennessee Valley Authority FACILITY: Watts Bar Nuclear Plant, Unit 2
SUBJECT:
SUMMARY
OF SEPTEMBER 26, 2017, PRESUBMITTAL MEETING WITH TENNESSEE VALLEY AUTHORITY REGARDING WATTS BAR NUCLEAR PLANT, UNIT 2 PENDING LICENSE AMENDMENT REQUEST TO LOAD TRITIUM PRODUCING BURNABLE ABSORBER RODS On September 26, 2017, a Category 1 public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of the Tennessee Valley Authority (TVA or the licensee) at NRC Headquarters, One White Flint North, 11555 Rockville Pike, Rockville, Maryland. The purpose of this meeting was for TVA staff to present information regarding (1) effluent dose limits and 2) spent fuel pool criticality in support of its pending (December 2017) license amendment request (LAR) to load tritium producing burnable absorber rods (TPBARs) in the Watts Bar Nuclear Plant (Watts Bar), Unit 2. The meeting notice and agenda, dated September 8, 2017, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML17268A216. Lists of attendees at both sessions of the meeting are enclosed with this memorandum.
During the first session (effluent dose limits), the licensee provided a presentation on the background, intent, technical basis, and schedule for the request. This presentation is available at ADAMS Accession No. ML17265A809. TVA staff began the presentation by providing an introduction and background for tritium production at Watts Bar. TVA staff stated that tritium production at Watts Bar, Unit 1 began in October 2003. However, the U.S. Department of Energy (DOE) subsequently determined that the amount of tritium being produced in Unit 1 was insufficient to meet stockpile needs and requested that tritium production be expanded to include Watts Bar, Unit 2. DOE notified TVA of the need for additional tritium in December 2015 and TVA agreed to this request in June 2016. TVA staff explained that the planned Watts Bar, Unit 2 LAR is in response to the DOE's request for additional tritium to support U.S. weapons stockpile needs and that its schedule supports DOE's schedule. The target for tritium production is to steadily ramp-up of production to approximately 2,800 grams every 18 months by December 2025. TVA plans to submit the LAR in December 2017, with requested approval by May 31, 2019, to support beginning production in November 2020.
TVA further discussed the project scope including plant modifications and engineering documentation, technical specification (TS) changes, and interface items. TVA stated it plans to increase the required minimum dilution flowrate setpoint from 20,000 gallons per minute (gpm) to 30,000 gpm, as part of the Watts Bar Unit 2 modifications. TVA also plans to add a reverse osmosis unit to the liquid radwaste system to provide additional capabilities for effluent management. However, TVA clarified that based on its evaluation of the impact on liquid radioactive effluents, this unit is not required to comply with the Title 1O of the Code of Federal Regulations (1 O CFR) Part 20.
TVA stated that the LAR for Unit 1 will be used as a precedent for the Unit 2 LAR. TVA will also provide discussions on the similarities and differences between the two units. The NRC staff noted that the Unit 1 LAR did not commit to NUREG-1672, "Safety Evaluation Report Related to the Department of Energy's Topical Report on the Tritium Production Core." The NRC staff asked whether TVA will use the same approach in the LAR for Unit 2. The NRC staff requested that TVA clearly indicate in the Watts Bar Unit 2 LAR where it follows the topical report and where it differs and that plant-specific items need to be discussed. TVA responded that the LAR will include new reactor vessel fluence evaluations for Unit 2 and new spent fuel rack criticality analyses for both Watts Bar Units 1 and 2.
During the meeting, the TVA stated that it will provide the results of an analysis of liquid and gaseous effluents that supports tritium production at Watts Bar, Unit 2. This new analysis will include the effects of tritium production at both Watts Bar, Units 1 and 2, updated primary and secondary radionuclide concentrations and the potential that minimum dilution flow required for radiological discharges into the cooling tower blowdown lines will increase. TVA stated that the results will demonstrate that the effluent concentration limits of Appendix B to 10 CFR Part 20 and the design guidelines of Appendix I to 10 CFR Part 50 will be met. The NRC staff noted that the effluent concentration results should also meet the Environmental Protection Agency's regulatory requirements in 40 CFR Part 190. TVA stated that its analysis was based on a "normal source term." The NRC staff clarified that there are different source terms that apply to different analyses and that this was a point of confusion between the staff and TVA for the recent Watts Bar, Unit 1, LAR to increase the number of TPBARs that can be irradiated. The staff clarified that there is a difference between a normal operating source term, an anticipated operational occurrence source term, a design-basis source term, and an accident source term.
TVA stated that it understood the distinctions and that the proper source term was used for the corresponding analysis in the development of the Watts Bar, Unit 2 LAR.
During the second session (spent fuel pool (SFP) criticality), TVA provided a presentation, which is available at ADAMS Accession No. ML17265A824. TVA explained that Watts Bar SFP racks, which originally resided in the Sequoyah Nuclear Plant, contains a single type of BORAL' racks and that no monitoring program was required at the time of licensing. The current SFP criticality analysis was performed by Holtec in 2000. The new analysis, which was also performed by Holtec, followed interim staff guidance (ISG) 2010-01, "Staff Guidance Regarding the Nuclear Criticality Safety Analysis for Spent Fuel Pools," and Nuclear Energy Institute (NEI) 12-16, "Guidance for Performing Criticality Analyses of Fuel Storage at Light-Water Reactor Power Plants." The analysis credits storage cell spacing, fixed neutron absorbers, and soluble Boron. TVA clarified that the Watts Bar Unit 2 LAR will include Unit 2 TPBARs; however, SFP criticality analysis will be provided for both Watts Bar units because Units 1 and 2 have a shared SFP.
TVA stated that the Watts Bar Unit 2 TPBAR LAR will propose changes to the Watts Bar TSs and adds several TSs for fuel storage and spent fuel pool. Specifically, TVA stated that TS 5.7.2.2.1, "Spent Fuel Storage Rack Neutron Absorber Monitoring Program," will be added to incorporate the NRG-approved topical report NEI 16-03-A, Revision 0, "Guidance for Monitoring of Fixed Neutron Absorbers in Spent Fuel Pools." NEI 16-03 offers two options for monitoring the condition of the neutron absorbing material in the SFP: In-situ testing (i.e.,
BADGER) and coupon testing. TVA faces challenges with both options. Watts Bar SFP storage racks have never had Boral' coupons; however, it is currently monitoring industry operating experience, participating in industry groups, monitoring fuel movement issues, and monitoring SFP chemistry. TVA believes that in-situ testing results will be overly conservative with BADGER; thus, TVA will consider harvesting coupons from an inservice Baral panel. TVA
further discussed issues with using a coupon program that should be resolved prior to using coupons. The NRC staff noted that one of challenges is with pre-characterizing coupons. The NRC staff also pointed out the structural integrity of the rack needs to be analyzed if coupons are harvested from the inservice Boral racks. TVA responded that it will carefully determine where to make the cuts, if that option is used.
The following action items were developed during the meeting.
From the first meeting, items to include in the TPBAR LAR
- Clearly state the areas where TVA is and is not following the topical report, especially where values are included.
- Regarding the new accident analyses, either provide the calculation or place it on a portal that can be accessed by NRC staff. Also, compare the calculation with NRC Regulatory Issue Summary 2006-04, "Experience with Implementation of Alternative Source Terms."
- Add a discussion of the 40 CFR Part 190 results and limits.
- Ensure that the discussion of realistic and design-basis source terms is clear.
- Ensure that the Watts Bar, Unit 2 contributions to the bioassay program and groundwater protection are clearly enumerated.
- Clearly state that because the TPBAR design ensures the criticality accident requirements of 10 CFR 50.68 are met, there is no environmental impact. Submit all the information for an environmental assessment with the LAR.
From the second meeting. item to include in the TPBAR LAR
- If the coupon program is pursued, ensure that a discussion of the structural integrity of the peripheral racks is included.
No regulatory decisions were made at the meeting. Four members of the public (one in person and three by teleconference), observed the first session. Three members of the public (one in person and two by teleconference), observed the second session of the meeting. No public meeting feedback forms were received.
Please direct any inquiries to me at 301-415-1447or Farideh.Saba@nrc.gov.
Farideh E. Saba, Senior Project Manager Plant Licensing Branch 2-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-391
Enclosures:
Lists of Attendees cc w/
Enclosures:
Distribution via Listserv
LIST OF ATTENDEES SEPTEMBER 26. 2017. MEETING WITH TENNESSEE VALLEY AUTHORITY REGARDING WATTS BAR NUCLEAR PLANT. UNIT 2. PENDING LICENSE AMENDMENT REQUEST TO LOAD TRITIUM PRODUCING BURNABLE ABSORBER RODS
- by teleconference Name Organization Farideh Saba U.S. Nuclear Regulatory Commission (NRC)
Undine Shoop NRC Kevin Hsueh NRC David Garmon NRC Ben Beasley NRC Bill Rautzen NRC Micheal Smith NRC Kristy Bucholtz* NRC Ed Schrull Tennessee Valley Authority (TVA)
Ben Hammargren TVA Mark Burzynski TVA Charles Davis TVA Steven Woods TVA Jeff McGuire TVA David Brown TVA Zita Martin TVA DouQ Pollock* TVA Kelly Cummins Department of Energy, National Nuclear Security Administration (NNSA)
Nanette Founds NNSA Robert Montgomery Public - Pacific Northwest National Laboratories (PNNL)
Ed Love* Public - PNNL David Senor* Public - PNNL Bill Freebairn* Public - S&P Global Platts Enclosure 1
LIST OF ATTENDEES SEPTEMBER 26. 2017. MEETING WITH TENNESSEE VALLEY AUTHORITY REGARDING WATTS BAR NUCLEAR PLANT. UNIT 2. PENDING LICENSE AMENDMENT REQUEST TO LOAD TRITIUM PRODUCING BURNABLE ABSORBER RODS SPENT FUEL POOL CRITICALITY
- by teleconference Name Organization Farideh Saba U.S. Nuclear Regulatory Commission (NRG)
Undine Shoop NRG Steven Bloom NRG Mathew Hamm NRG Alex Cherskin NRG Amrit Patel NRG Matt Yoder NRG Scott Krepel NRG Nate Jordan NRG Ed Schrull Tennessee Valley Authority (TVA)
Ben Hammargren TVA Mark Burzynski TVA Charles Davis TVA Steven Woods TVA Jeff McGuire TVA David Brown TVA Zita Martin TVA Doug Pollock* TVA Mike Pamula Holtec (TVA contractor)
Matt Ogrinc Evan Rosenbaum Bret Brickner Kelly Cummins Department of Energy, National Nuclear Security Administration (NNSA)
Nanette Founds NNSA Robert Montgomery Public - Pacific Northwest National Laboratories (PNNL)
Ed Love* Public - PNNL David Senor* Public - PNNL Enclosure 2
SUBJECT:
SUMMARY
OF SEPTEMBER 26, 2017, PRESUBMITTAL MEETING WITH TENNESSEE VALLEY AUTHORITY REGARDING WATTS BAR NUCLEAR PLANT, UNIT 2 PENDING LICENSE AMENDMENT REQUEST TO LOAD TRITIUM PRODUCING BURNABLE ABSORBER RODS DATED OCTOBER 26, 2017 DISTRIBUTION:
PUBLIC SKrepel, NRR RidsACRS_MailCTR ACherskin, NRR RidsNrrDorl APatel, NRR RidsNrrDorlLpl2-2 NJordan, NRR RidsNrrDraArcb MHamm, NRR RidsRgn2MailCenter MYoder, NRRN RidsN rrPMW attsBar DBrown, NRR RidsN rrLABClayton BRautzen, NRR FSaba, NRR MSmith, NRR TWertz, NRR JBowen, OEDO KBucholtz, NRR RidsNrrDmlrMenb RidsNrrDmlrMccb RidsN rrDssSnpb DGarmon, NRR ADAMS Access1on No.: ML17297A044 *b1y e-ma1*1 OFFICE DORULP2-2/PM DORULP2-2/LA ORA/ARCS/BC DSS/SNPB/BC*
BClayton NAME FSaba (LRonewicz, for) KHsueh RLukes DATE 10/26/2017 10/25/2017 10/26/2017 10/24/2017 OFFICE DMLR/MCCB/BC* DMLR/MENB/BC* DORULP2-2/BC DORULP2-2/PM BBeasley (JRikhoff, NAME SBloom for) UShoop FSaba DATE 10/25/2017 10/25/2017 10/26/2017 10/26/2017 OFFICIAL RECORD COPY