ML20280A695
| ML20280A695 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 10/13/2020 |
| From: | Booma Venkataraman NRC/NRR/DORL/LPL3 |
| To: | Entergy Nuclear Operations |
| Venkataraman B | |
| Shared Package | |
| ML20280A694 | List: |
| References | |
| EPID L-2020-LRO-0051 | |
| Download: ML20280A695 (6) | |
Text
October 13, 2020 Vice President, Operations Entergy Nuclear Operations, Inc.
Echelon One 1340 Echelon Parkway Jackson, MS 39213
SUBJECT:
PALISADES NUCLEAR PLANT -
SUMMARY
OF SEPTEMBER 11, 2020, CONFERENCE CALL WITH ENTERGY NUCLEAR OPERATIONS INC.
REGARDING THE FALL 2020 STEAM GENERATOR TUBE INSPECTIONS AT PALISADES NUCLEAR PLANT (EPID L-2020-LRO-0051)
Dear Sir or Madam:
On September 11, 2020, a conference call was held between the U.S. Nuclear Regulatory Commission (NRC) staff and representatives of Entergy Nuclear Operations Inc. (the licensee) regarding the ongoing steam generator inspection activities at Palisades Nuclear Plant. A list of the participants is provided as Enclosure 1. The conference call summary is provided as. The licensee-provided draft information for the outage call on September 9, 2020 (Agencywide Documents Access and Management System (ADAMS) ML20280A697), with responses to staff questions and then subsequently updated the information after the call and provided a revised document on September 12, 2020 (ADAMS Accession No. ML20280A696).
Based on the information provided by the licensee, the NRC staff did not identify any issues that warranted immediate follow-up action. However, the NRC staff asked to be notified if any unusual conditions were detected during the remainder of the outage.
If you have any questions, please contact me at 301-415-2934 or via e-mail at Booma.Venkataraman@nrc.gov.
Sincerely,
/RA/
Booma Venkataraman, Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-255
Enclosures:
- 1. List of Participants
- 2. Conference Call Summary cc: Listserv
ML20280A694 (Package)
OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DORL/LPL3/BC NAME BVenkataraman SRohrer NSalgado DATE 10/06/20 10/13/20 10/13 /20 OFFICE NRR/DORL/LPL3/PM NAME BVenkataraman DATE 10/13/20
LIST OF PARTICIPANTS SEPTEMBER 11, 2020, CONFERENCE CALL WITH ENTERGY NUCLEAR OPERATIONS, INC.
PALISADES NUCLEAR PLANT FALL 2020 STEAM GENERATOR TUBE INSPECTIONS DOCKET NO. 50-255 U.S. NUCLEAR REGULATORY COMMISSION Andrew Johnson Paul Klein George Makar Booma Venkataraman Leslie Terry Paul Laflamme Courtney St. Peters ENTERGY NUCLEAR OPERATIONS INC.
Jim Miksa Barb Dorson Dustin Daggett FRAMATOME Dan Meatheany Celeste Bell Craig Kelley
CONFERENCE CALL
SUMMARY
SEPTEMBER 11, 2020, CONFERENCE CALL WITH ENTERGY NUCLEAR OPERATIONS, INC.
PALISADES NUCLEAR PLANT FALL 2020 STEAM GENERATOR TUBE INSPECTIONS DOCKET NO. 50-255 On September 11, 2020, the U. S. Nuclear Regulatory Commission (NRC) staff (including staff from the Corrosion and Steam Generator Branch of the Division of New and Renewed Licenses) participated in a conference call with Entergy Nuclear Operations, Inc. (the licensee),
regarding the ongoing steam generator (SG) inspection activities at Palisades Nuclear Plant.
The licensee-provided draft information for the outage call on September 9, 2020 (Agencywide Documents Access and Management System (ADAMS) ML20280A697), with responses to staff questions in Enclosure 3, and then subsequently updated the information after the call and provided a revised document on September 12, 2020 (ADAMS Accession No. ML20280A696).
Palisades has two Combustion Engineering Model 2530 replacement SGs. Each SG has 8,219 mill-annealed Alloy 600 tubes with a nominal outside diameter of 0.750 inches and a nominal wall thickness of 0.042 inches. Stainless steel, lattice-type tube supports, diagonal straps, and vertical straps support the tubes at various locations. The tubes were expanded through the full depth of the tubesheet using an explosive process.
The following abbreviations are in the September 12, 2020, document provided by the licensee:
%TW - Percent Through-Wall
+Pt - Plus-point AILPC - Accident Induced Leakage Performance Criteria C* - C-star CL - Cold Leg ECT - Eddy Current Testing EFPY - Effective Full Power Year EPRI - Electric Power Research Institute ETSS - Examination Technique Specification Sheet GPD - Gallons Per Day HL - Hot Leg N/A - Not Applicable NDE - Non-Destructive Examination PDA - Percent Degraded Area psi - pounds per square inch 1R27 or RF27 - Unit 1 Refueling Outage 27 RPC - Rotating Pancake Coil SIPC - Structural Integrity Performance Criteria TEC - Tube End Cold TEH - Tube End Hot TRA - Trackable Anomaly TSPs - Tube Support Plates TSH - Tubesheet Hot TTS - Top-of-tubesheet TW - Through-Wall V - Volts The NRC staff discussed several topics regarding the ongoing inspections during the conference call with the licensee. Information exchanged during the call and not included in the licensee-provided information is summarized below:
At the time of the call, the eddy current inspections were 97 percent complete.
The staff inquired if any of the SG tube eddy current indications could be sources of the very low-level primary-to-secondary leakage noted during the previous operating cycle.
The licensee stated that none of the indications detected during the outage were deep enough to be considered a source of the primary-to-secondary leakage.
At the time of the call, the licensee had identified 31 tubes in SG A and 17 tubes in SG B that required plugging. This number is higher than indicated in the document provided by the licensee, which had been developed when inspections were only 90 percent complete.
In response to a staff question, the licensee noted that the 100 percent inspection of historical trackable indications included approximately three to four objects that are just outside some tubes that have been tracked since the initial baseline inspection of the SGs. The indications have been monitored every outage with no change.
The staff asked about the sizing parameters of the two axial outside diameter stress corrosion cracking indications in SG B that were closest to the condition monitoring limit, as shown in the figure on page 5 of the document provided by the licensee. The licensee stated the sizing parameters were:
o a maximum depth of 55 percent TW, a maximum length of 0.46 inches, and a signal amplitude of 0.51 volts; o a maximum depth of 62 percent TW, a maximum length of 0.3 inches, and a signal amplitude of 0.76 volts.
The licensee confirmed that the current inspection is the last planned SG inspection before plant shutdown.
The staff asked to be contacted by the licensee if they experienced any unexpected or unusual inspection findings in the remainder of the SG inspections.
The NRC staff did not identify any issues that required follow-up action at the time of the call.
After the call, the NRC staff noted a numerical discrepancy in the September 9, 2020, document provided by the licensee. The licensee-provided an updated document that corrected the discrepancy on September 12, 2020.