ML17093A917
| ML17093A917 | |
| Person / Time | |
|---|---|
| Site: | Hatch, Vogtle  |
| Issue date: | 04/21/2017 |
| From: | Michael Orenak Plant Licensing Branch II |
| To: | Southern Nuclear Operating Co |
| Orenak M | |
| References | |
| CAC MF9350, CAC MF9351 | |
| Download: ML17093A917 (5) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 April 21, 2017 LICENSEE: Southern Nuclear Operating Company FACILITY: Edwin I. Hatch Nuclear Plant, Unit Nos. 1 and 2, and Vogtle Electric Generating Plant, Units 1 and 2
SUBJECT:
SUMMARY
OF MARCH 23, 2017, PRE-SUBMITTAL PUBLIC MEETING WITH SOUTHERN NUCLEAR OPERATING COMPANY, INC. TO DISCUSS THE PROPOSED LICENSE AMENDMENT REQUESTS REGARDING TSTF-542, "REACTOR PRESSURE VESSEL WATER INVENTORY CONTROLS," AND SURVEILLANCE REQUIREMENT 3.3.1.3 (CAC NOS. MF9350 AND MF9351)
On March 23, 2017, a Category 1 pre-submittal public teleconference was held between the U.S. Nuclear Regulatory Commission (NRC) staff and representatives of Southern Nuclear Operating Company, Inc. (SNC, the licensee). The purpose of the meeting was to discuss with the SNC staff its planned proposed license amendment submittals regarding (1) Technical Specification Task Force (TSTF)-542, "Reactor Pressure Vessel Water Inventory Controls," for the Edwin I. Hatch Nuclear Plant (HNP), Unit Nos. 1 and 2 and (2) a change to the NOTE of Technical Specifications Surveillance Requirement 3.3.1.3 concerning the in-core detector surveillances at the Vogtle Electric Generating Plant (VEGP), Units 1 and 2.
The meeting notice and agenda, dated March 13, 2017, are located at Agencywide Documents Access and Management System (ADAMS) Accession No. ML17079A033. The licensee's presentation slides are available in ADAMS at Package Accession No. ML17076A433. A list of meeting attendees is provided in the enclosure to this meeting summary.
Meeting Summary After introductions, the licensee proceeded into the discussions of the TSTF-542 variations for HNP, Unit Nos. 1 and 2. The NRC staff first provided an overall comment regarding the proposed changes to the HNP technical specifications (TS). The NRC staff noted that the descriptions provided in the draft document were difficult to follow and suggested that additional clarifications and/or be provided in the submittal.
The NRC staff inquired if the TS Table 3.3.5.1-1 functions are moving to TS Table 3.3.5.2-1.
The licensee stated that the changes are editorial in nature and clarifications will be made in the actual submittal.
The licensee discussed the proposed variations from TSTF-542 associated with the manual initiation logic for the core spray (CS) and low pressure coolant injection (LPCI) subsystems (last bullet on page 2 of 5 of the variation descriptions). The licensee stated that since HNP does not include a manual initiation logic function in its design for the CS or LPCI subsystems (similar to Dresden Nuclear Power Station), the associated TSTF-542 TS changes are not included in the variations for this function.
During the discussion of the surveillance requirement (SR) provided on page 3, the NRC staff
asked if the SR is a brand new surveillance, or if it has been moved from another location in the TS. The licensee stated that the surveillance is new because the TS does not have a SR requiring manual operation of the emergency cool cooling system (ECCS) injection/spray subsystem. However, they do operate the ECCS pumps during the required quarterly test with a manual initiation. The NRC staff requested the licensee to clarify if the change is editorial or a new technical change. The licensee agreed to clarify the intent and contest for the change.
The licensee requested that the proposed amendment be approved prior to the next refueling outage. The NRC staff suggests the submitted LAR describe the operational need for having the amendment issued by the requested date. The licensee stated that they planned to submit the amendment in early April 2017.
After a short break, the licensee discussed the proposed change to the VEGP SR 3.3.1.3. The NRC staff first requested information on the purpose of the change (i.e., the basis for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, or inaccuracy at 15 percent power) that was the basis of the operational difficulty. The licensee stated that the combination of the power and the time is creating difficulty. In particular, the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and 15 percent power contained within the NOTE in SR 3.3.1.3 is a backstop, meaning the surveillance can be done prior to 15 percent power at any time, but must be completed 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after surpassing 15 percent power. The operational difficulty arises when in-core detectors are inaccurate at 15 percent power because the plant is unstable during that stage of the power ascension, resulting in an inaccurate projection at 100 percent power. When the plant passes 20 percent power, the power ascension stops for operational needs and the reactor core is stable enough to take an accurate measurement. However, the licensee only has 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after passing 15 percent power to complete the surveillance measurements (the measurements take a couple hours}, so the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> limit results in a challenging time constraint on operations to take the measurements in time.
The NRC staff asked the licensee to clarify if its priority is a stable reactor core or an accurate measurement. The licensee stated they foremost want a stable reactor core due to the couple hours required to take the measurements.
The licensee also discussed provided some history for the note in SR 3.3.1.3. The original licensing basis for VEGP used the Constant Axial Offset Control (CAOC) methodology, and the TS 3.2.3 applicability was 15 percent, which is why the SR 3.3.1.3 NOTE currently requires 15 percent. In the 1990s, Westinghouse changed the methodology to the Relaxed Offset Control (RAOC) methodology, which resulted in 50 percent reactor power being needed for determining axial flux difference. The 15 percent in SR 3.3.1.3 had been a legacy value that should have been changed when the methodology was changed. Specifically, for VEGP, the methodology was changed on September 19, 1991, in amendment numbers 43 and 44 for VEGP, Unit 1, and amendment numbers 23 and 24 for VEGP, Unit 2 (ADAMS Accession No. ML012290256), respectively.
The NRC staff asked for the reasons that the change is being requested now, considering that VEGP has used 15 percent for the past 20 years. The licensee stated that recalibrating the instruments within the required 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is difficult. The 15 percent threshold is too low and calibrating the incore detectors takes several hours. The 50 percent is consistent with the safety analysis that stated the axial flux difference is not controlled below 50 percent reactor power.
The NRC staff asked if the SR 3.3.1.3 NOTE from 15 percent to 50 percent power will change any of the Updated Final Safety Analysis Report (UFSAR) Chapter 15 analyses. The licensee
stated that the UFSAR analyses already incorporate the 50 percent change due to the September 19, 1991, approval of amendment numbers 43 and 44 for VEGP, Unit 1, and amendment numbers 23 and 24 for VEGP, Unit 2, respectively.
No members of the public were in attendance. No Public Meeting Feedback Forms were received.
Please direct any inquiries to me at 301-415-3229 or Michael.Orenak@nrc.gov.
M~
Michael D Orenak, Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-321, 50-366, 50-424, and 50-425
Enclosure:
List of Attendees
LIST OF ATTENDEES MARCH 23, 2017, PUBLIC TELECONFERENCE WITH SOUTHERN NUCLEAR OPERATING COMPANY, INC.
REGARDING TSTF-542 FOR EDWIN I. HATCH NUCLEAR PLANT, UNIT NOS. 1 AND 2 AND SURVEILLANCE REQUIREMENT 3.3.1.3 FOR VOGTLE ELECTRIC GENERATING PLANT, UNITS 1 AND 2 NAME ORGANIZATION Michael Orenak U.S. Nuclear Regulatory Commission (NRC)
Russ Haskell NRC Rossnyev Alvarado NRC Diana Woodyatt NRC Margaret Chernoff NRC Khadijah West NRC Randy Hall NRC Alex Klein NRC Muhammad Razzaque NRC Summer Sun NRC Hang Vu NRC Ryan Joyce Southern Nuclear Operating Company (SNC)
Ozzie Vidal SNC Jimmy Collins SNC Bob Florian SNC Gary Smith SNC Enclosure
ML17093A917 OFFICE NRR/DORL/LPL2-1/PM NRR/DORL/LPL2-1/LA NRR/DE/EICB/BC N RR/DSS/STSB/BC MWaters AKlein NAME MOrenak KGoldstein (RAlvarado for)
DATE 4/12/2017 4/11/2017 4/12/2017 4/14/2017 OFFICE NRR/DSS/SRXB/BC NRR/DORL/LPL2-1/BC NRR/DORL/LPL2-1/PM NAME EOesterle MMarkley MOrenak DATE 4/17/2017 4/21/2017 4/21/2017