ND-22-0747, ITAAC Closure Notification on Completion of ITAAC 2.1 .02.08d.ii (Index Number 33)

ITAAC Closure Notification on Completion of ITAAC 2.1 .02.08d.ii (Index Number 33)

ML22355A605
Person / Time
Site:	Vogtle
Issue date:	12/21/2022
From:	Coleman J Southern Nuclear Operating Co
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
ND-22-0747
Download: ML22355A605 (1)

Text

Jamie M. Coleman 3/4e: Southern Nuclear Regulatory Affairs Director Vogtle 3 & 4 7825 River Road Waynesboro, GA 30830 706-848-6926 tel December 21, 2022 Docket No.: 52-026 ND-22-0747 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 4 ITAAC Closure Notification on Completion of ITAAC 2.1 .02.08d.ii (Index Number 33]

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 4 Inspections, Tests, Analyses and Acceptance Criteria (ITAAC) Item 2.1.02.08d.ii [Index Number 33] for verifying the line routing is consistent with the line routing used for design flow resistance calculations and is less than or equal to the calculated flow resistance of each Automatic Depressurization System (ADS) fourth-stage sub-loops. 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 was 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, f ;}PyfZ_~

Jamie M. Coleman

~( ~6\C Regulatory Affairs Director Vogtle 3 & 4

Enclosure:

Vogtle Electric Generating Plant (VEGP) Unit 4 Completion of ITMC 2.1.02.08d.ii flndex Number 33]

JMC/PAW/sfr

U.S. Nuclear Regulatory Commission ND-22-0747 Page 2 of 2 cc: Regional Administrator, Region II Director, Office of Nuclear Reactor Regulation (NRA)

Director, Vogtle Project Office NRR Senior Resident Inspector - Vogtle 3 & 4

U.S. Nuclear Regulatory Commission ND-22-0747 Enclosure Page 1 of 4 Southern Nuclear Operating Company ND-22-0747 Enclosure Vogtle Electric Generating Plant (VEGP) Unit 4 Completion of ITAAC 2.1.02.0Bd.ii [Index Number 33]

U.S. Nuclear Regulatory Commission ND-22-0747 Enclosure Page 2 of 4 ITAAC Statement Design Commitment:

8.d) The RCS provides automatic depressurization during design basis events.

Inspections, Tests, Analyses:

ii) Inspections and associated analysis of each fourth-stage ADS valve group (four valves and associated piping connected to each hot leg) will be conducted to verify the line routing is consistent with the line routing used for design flow resistance calculations.

Acceptance Criteria:

ii) The calculated flow resistance for each group of fourth-stage ADS valves and piping with all valves open is:

Loop 1:

Sub-loop A: s 5.91x10- 7 ft/gpm 2 Sub-loop C: s 6.21x10-7 ft/gpm 2 Loop 2:

Sub-loop B: s 4.65x10-7 ft/gpm 2 Sub-loop D: s 6.20x10-1 ft/gpm 2 ITAAC Determination Basis Multiple ITAAC are performed to demonstrate the Reactor Coolant System (RCS) provides automatic depressurization during design basis events. This ITAAC performed inspections and analysis of each fourth-stage Automatic Depressurization System (ADS) valve group (four valves and associated piping connected to each hot leg) to verify the line routing is consistent with the line routing used for design flow resistance calculations.

A flow resistance was calculated with Darcy's formula for each of the fourth-stage ADS sub-loops flow paths A, B, C, and D using line routing information (i.e., pipe length, pipe diameter, number and type of pipe fittings, entrance/exit losses, and valves) (Reference 1). Following installation, inspections of each sub-loop's as-built construction records were performed to verify the line routing information from the hot leg of the RCS to the discharge of the fourth-stage squib valves remained consistent with the information in the flow resistance design calculation.

The results were used to calculate the as-built flow resistance for each sub-loop using the same methodology used in the flow resistance design calculation and compared to the ITAAC acceptance criteria (Reference 2).

The results documented in Reference 2 and shown in Attachment A demonstrate the ITAAC acceptance criteria is met.

References 1 and 2 are available for NRC inspection as part of the Unit 4 ITAAC 2.1 .02.0Sd.ii Completion Package (Reference 3).

U.S. Nuclear Regulatory Commission ND-22-0747 Enclosure Page 3 of 4 ITAAC Finding Review In accordance with plant procedures for ITAAC completion, Southern Nuclear Operating Company (SNC) performed a review of all lTAAC findings pertaining to the subject ITAAC and associated corrective actions. This review found that there are no relevant ITAAC findings associated with this ITAAC. This ITAAC completion review is documented in the ITAAC Completion Package (Reference 3) and is available for NRC review.

ITAAC Completion Statement Based on the above information, SNC hereby notifies the NRC that ITAAC 2.1.02.0Bd.ii was performed for VEGP Unit 4 and that the prescribed acceptance criteria are 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. APP-PXS-M3C-019, Rev. 5, "IRWST / Containment Sump Injection Lines and ADS Line Resistances"

2. SV4-RCS-ITR-800033, Rev. 0, "Unit 4 Inspections and Associated Analysis of each fourth-stage ADS Sub-loop: ITAAC 2.1.02.0Bd.ii"

3. 2.1.02.08d.ii-U4-CP-Rev0, ITAAC Completion Package

U.S. Nuclear Regulatory Commission ND-22-0747 Enclosure Page 4 of 4 Attachment A Fourth-Stage ADS Loop Flow Resistance Calculated ITAAC Fourth-stage As-built Flow Acceptance Loop Squib valve Resistance+ Criteria*

Tag No.*

(ft/gpm 2) (ft/gpm2)

Sub-loop A RCS-PL-V004A < 5.76x10-7 s 5.91 x10- 7 Sub-loop B RCS-PL-V004B < 4.4Bx10-7 s 4.65x10-7 Sub-loop C RCS-PL-V004C < 5.98x10-7 s 6.21x10-7 Sub-loop D RCS-PL-V004D < 5.97x10-7 s 6.20x10-7

• Excerpt from COL App C Tables 2.1 .2-1 and 2.1.2-4

+ Results are Unit specific