ND-21-0868, ITAAC Closure Notification on Completion of ITAAC 2.2.03.08b.01 (Index Number 175)

ITAAC Closure Notification on Completion of ITAAC 2.2.03.08b.01 (Index Number 175)

ML21270A105
Person / Time
Site:	Vogtle
Issue date:	09/24/2021
From:	Yox M Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
ND-21-0868
Download: ML21270A105 (6)

Text

Michael J. Yox

^Southern Nuclear Regulatory Affairs Director Vogtle 3 & 4 7825 River Road Waynesboro, GA 30830 706-848-6459 tel SEP 2 h 2021 Docket No.;52-025 ND-21-0868 10 CFR 52.99(c)(1)

U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001 Southern Nuclear Operating Company Vogtle Electric Generating Plant Unit 3 ITAAC Closure Notification on Completion of ITAAC 2.2.03.08b.01 [Index Number 1751 Ladies and Gentlemen:

In accordance with 10 CFR 52.99(c)(1), the purpose of this letter is to notify the Nuclear Regulatory Commission (NRC) of the completion of Vogtle Electric Generating Plant(VEGP)

Unit 3 Inspections, Tests, Analyses, and Acceptance Criteria (ITAAC) Item 2.2.03.08b.01 [Index Number 175]. This ITAAC verified that the PRHR Heat Exchanger could remove core decay heat during design basis events. This closure notification differs from the Uncompleted ITAAC Notification in that the LOFTRAN model was utilized to address the different initial conditions of the test (i.e., the Hot Leg (HL) and In-containment Refueling Water Storage Tank (IRWST) temperatures and the number of tubes plugged) to validate the PRHR Heat Exchanger performance. The closure process for this ITAAC is based on the guidance described in NEI 08-01,"Industry Guideline for the ITAAC Closure Process under 10 CFR Part 52", which is endorsed by the NRC in Regulatory Guide 1.215.

This letter contains no new NRC regulatory commitments. Southern Nuclear Operating Company(SNC) requests NRC staff confirmation of this determination and publication of the required notice in the Federal Register per 10 CFR 52.99.

If there are any questions, please contact Kelli Roberts at 706-848-6991.

Respectfully submitted.

Michael J. Yox ^

Regulatory Affairs Di/ector Vogtle 3 & 4

Enclosure:

Vogtle Electric Generating Plant(VEGP) Unit 3 Completion of ITAAC 2.2.03.08b.01 [Index Number 175]

MJY/DLW/sfr

U.S. Nuclear Regulatory Commission ND-21-0868 Page 2 of 3 To:

Southern Nuclear Operating Companv/ Georgia Power Company Mr. Peter P. Sena III Mr. D. L. McKinney Mr. H. Nieh Mr. M. D. Meier Mr. G. Chick Mr. S. Stimac Mr. P. Martino Mr. M. J. Yox Mr. A. S. Parton Ms. K. A. Roberts Ms. J.M. Coleman Mr. C. T. Defnall Mr. C. E. Morrow Mr. K. J. Drudy Mr. J. M. Fisher Mr. R. L. Belike Mr. S. Leighty Ms. A. C. Chamberlain Mr. J. C. Haswell Document Services RTYPE: VND.LI.L06 File AR.01.02.06 cc:

Nuclear Regulatory Commission Ms. M. Bailey Mr. M. King Mr. G. Bowman Ms. A. Veil M C. P. Patel M G. J. Khouri M C. J. Even M B. J. Kemker Ms. N. C. Coovert Mr. C. Welch Mr. J. Gaslevic Mr. O. Lopez-Santiago Mr. G. Armstrong Mr. M. Webb Mr. T. Fredette Mr. C. Santos Mr. B. Davis Mr. J. Vasquez Mr. J. Eargle Mr. E. Davidson Mr. T. Fanelli Ms. K. McCurry Mr. J. Parent Mr. B. Griman

U.S. Nuclear Regulatory Commission ND-21-0868 Page 3 of 3 Oqlethorpe Power Corporation Mr. R. B. Brinkman Mr. E. Rasmussen Municipal Electric Authority of Georgia Mr. J. E. Fuller Mr. 8. M. Jackson Daiton Utilities Mr. T. Bundros Westinahouse Electric Company. LLC Dr. L. Oriani Mr. D. C. Durham Mr. M. M. Corletti Mr. Z. 8. Harper Mr. J. L. Coward Other Mr. 8. W. Kline, Bechtel Power Corporation Ms. L. Matis, Tetra Tech NUS, Inc.

Dr. W. R. Jacobs, Jr., Ph.D., CDS Associates, Inc.

Mr. 8. Roetger, Georgia Public Service Commission Mr. R. L. Trokey, Georgia Public Service Commission Mr. K. C. Greene, Troutman Sanders Mr. 8. Blanton, Batch Bingham

U.S. Nuclear Regulatory Commission ND-21-0868 Enclosure Page 1 of 3 Southern Nuclear Operating Company ND-21-0868 Enclosure Vogtle Electric Generating Plant(VEGP) Unit 3 Completion of ITAAC 2.2.03.08b.01 [Index Number 175]

U.S. Nuclear Regulatory Commission ND-21-0868 Enclosure Page 2 of 3 ITAAC Statement Design Commitment 8.b) The PXS provides core decay heat removal during design basis events.

Inspections/Tests/Analvses

1. A heat removal performance test and analysis of the PRHR HX will be performed to determine the heat transfer from the HX. For the test, the reactor coolant hot leg temperature will be initially at a 350°F with the reactor coolant pumps running. The IRWST water level for the test will be above the top of the HX. The test will continue until the hot leg temperature is

< 250°F.

Acceptance Criteria

1. A report exists and concludes that the PRHR HX heat transfer rate with the design basis number of PRHR HX tubes plugged is; a 8.46 X 10^ Btu/hr with 250°F HL Temp and an initial IRWST temperature of 80°F.

The heat transfer rate measured in the test should be adjusted to account for differences in the HL and IRWST temperatures and the number of tubes plugged.

ITAAC Determination Basis Multiple ITAAC are performed to confirm the Passive Core Cooling System provides core decay heat removal during design basis events by testing and analysis of the Passive Residual Heat Removal(PRHR) Heat Exchanger(HX)subsystem to determine the heat transfer from the PRHR HX. The Reactor Coolant System (RCS) hot leg temperature will be initially ^ 350°F with the Reactor Coolant Pumps(RCPs) running. The In-containment Refueling Water Storage Tank (IRWST) water level for the test will be above the top of the PRHR HX, and the test will continue until the hot leg (HL)temperature is ^ 250°F.

The testing was performed in accordance with Unit 3 Work Order and Preoperational test procedure as documented in Reference 1 during Hot Functional Testing with the RCS at s 350°F, and the IRWST level was verified to be above the PRHR HX. The RCPs were verified to be running and the test was initiated by opening one of the PRHR HX outlet valves. RCS temperature was monitored, and the PRHR HX outlet valve was closed when temperature decreased to ^ 250°F. PRHR HX inlet temperature, RCS hot leg and cold leg temperatures, IRWST temperature and PRHR HX flow were trended during the test, and this information was provided to engineering to perform the heat transfer rate calculations.

As the actual test conditions differ from the assumptions originally used to develop the ITAAC acceptance criteria of 8.46 x 10^ Btu/hr, the heat transfer rate calculated using the UFSAR Chapter 15 LOFTRAN safety analysis code model was adjusted to account for differences in the initial conditions for the test (i.e., the HL and IRWST temperatures and the number of tubes plugged). This adjustment of the acceptance criteria using the LOFTRAN model is necessary to ensure a relevant, conservative comparison of the test results to the heat transfer rates predicted for the test using the LOFTRAN code.

U.S. Nuclear Regulatory Commission ND-21-0868 Enclosure Page 3 of 3 The as-tested performance of the PRHR HX subsystem yielded a heat transfer rate of 8.3916x10 Btu/hr. The equivalent calculation using the conservative LOFTRAN model yielded a heat transfer rate of 7.9474x10^ Btu/hr. As stated in Reference 2, this comparison clearly demonstrates that the actual PRHR HX subsystem performance exceeds that predicted In the LOFTRAN model at the as-tested conditions. As the test performed demonstrates that the PRHR HX subsystem meets Its design basis, It can be concluded that the PRHR HX subsystem would also meet the heat transfer capability at the safety analysis conditions associated with the 8.46x10^ Btu/hr value In the ITAAC acceptance criteria. As such, this ITAAC Is determined to be met.

References 1 and 2 are available for NRG Inspection as well as the ITAAC 2.2.03.08b.01 Completion Package (Reference 3).

ITAAC Finding Review In accordance with plant procedures for ITAAC completion. Southern Nuclear Operating Company(SNC) performed a review of all findings pertaining to the subject ITAAC and associated corrective actions. This review found there are no relevant ITAAC findings associated with this IT/\AC. The ITAAC completion review Is documented In the IT/\AC Completion Package for \TAAC 2.2.03.08b.01 (Reference 3) and Is available for NRC review.

ITAAC Completion Statement Based on the above Information, SNC hereby notifies the NRC that IT/VAC 2.2.03.08b.01 was performed for VEGP Unit 3 and that the prescribed acceptance criteria were met.

Systems, structures, and components verified as part of this ITAAC are being maintained In their as-designed, ITAAC compliant condition In accordance with approved plant programs and procedures.

References(available for NRC inspection)

1. SV3-PXS-ITR-800175, Rev. 0,"Unit 3 Recorded Results of PRHR Heat Exchanger Heat Transfer Rate Test: ITAAC 2.2.03.08b.01"

2. SV3-PXS-T2C-011, Rev. 0,"Vogtle Unit 3 PXS Hot Functional Test Results Validation for PRHR Performance"

3. 2.2.03.08b.01-U3-CP-RevO, IT/\AC Completion Package