ML19172A119

COL Docs - Vogtle June 27 Pre-Submittal Meeting - Pressurizer Surge Line Draft LAR

ML19172A119
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Site:	Vogtle
Issue date:	06/21/2019
From:	NRC
To:	NRC/NRO/DLSE/LB4
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Download: ML19172A119 (24)

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Vogtle PEmails From: Rankin, Jennivine Sent: Friday, June 21, 2019 10:22 AM To: Vogtle PEmails

Subject:

Vogtle June 27 Pre-Submittal Meeting - Pressurizer Surge Line DRAFT LAR Attachments: ND-19-0670 Pzr Surge Line LAR DRAFT.PDF Jennie Rankin, Project Manager Licensing Branch 2 Division of Licensing, Siting, and Environmental Analysis Office of New Reactors 1

Hearing Identifier: Vogtle_COL_Docs_Public Email Number: 458 Mail Envelope Properties (BN6PR09MB22278678108B0E5773727AE598E70)

Subject:

Vogtle June 27 Pre-Submittal Meeting - Pressurizer Surge Line DRAFT LAR Sent Date: 6/21/2019 10:22:00 AM Received Date: 6/21/2019 10:22:07 AM From: Rankin, Jennivine Created By: Jennivine.Rankin@nrc.gov Recipients:

"Vogtle PEmails" <Vogtle.PEmails@nrc.gov>

Tracking Status: None Post Office: BN6PR09MB2227.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 156 6/21/2019 10:22:07 AM ND-19-0670 Pzr Surge Line LAR DRAFT.PDF 805470 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received:

Michael J. Yox 7825 River Road Regulatory Affairs Director Waynesboro, GA 30830 Vogtle 3 & 4 706-848-6459 tel Docket Nos.: 52-025 ND-19-0670 52-026 10 CFR 50.90 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001 Southern Nuclear Operating Company Vogtle Electric Generating Plant Units 3 and 4 T

Request for License Amendment:

Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX)

Ladies and Gentlemen:

AF Pursuant to 10 CFR 52.98(c) and in accordance with 10 CFR 50.90, Southern Nuclear Operating Company (SNC), the licensee for Vogtle Electric Generating Plant (VEGP) Units 3 and 4, requests an amendment to Combined License (COL) Numbers NPF-91 and NPF-92, for VEGP Units 3 and 4, respectively.

Specifically, the requested amendment would eliminate COL condition 2.D.(2)(a)1 which R

describes a first plant Pressurizer Surge Line Stratification Evaluation and makes related revisions to the Vogtle 3 and 4 Updated Final Safety Analysis Report Tier 2 information. Because this change would modify the COL, this amendment request requires prior NRC approval. provides the description, technical evaluation, regulatory evaluation (including the no D

significant hazards consideration analysis), and environmental considerations for the proposed changes. provides the proposed changes to the licensing basis documents.

This letter contains no regulatory commitments. This letter has been reviewed and confirmed to contain no security-related information.

U.S. Nuclear Regulatory Commission ND-19-0670 Page 2 of 4 SNC requests NRC staff review and approval of the license amendment request (LAR) no later than [month day, year]. Approval by this date will allow sufficient time to implement licensing basis changes necessary for the scheduling of pressurizer purge line testing activities. SNC expects to implement the proposed amendment within thirty days of approval of the LAR.

In accordance with 10 CFR 50.91, SNC is notifying the State of Georgia of this LAR by transmitting a copy of this letter and enclosures to the designated State Official.

Should you have questions regarding this submittal, please contact Mr. Steven Leighty at (706) 848-6790.

I declare under penalty of perjury that the foregoing is true and correct. Executed on this XX day of XXXX 2019.

Respectfully submitted, T Michael J. Yox Regulatory Affairs Director Vogtle 3 & 4 AF SOUTHERN NUCLEAR OPERATING COMPANY MJY/RAS/sfr

Enclosures:

1)

R Vogtle Electric Generating Plant (VEGP) Units 3 and 4 - Request for License D 2)

Amendment: Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX)

Vogtle Electric Generating Plant (VEGP) Units 3 and 4 - Proposed Changes to Licensing Basis Documents (LAR-19-XXX)

U.S. Nuclear Regulatory Commission ND-19-0670 Page 3 of 4 cc:

Southern Nuclear Operating Company / Georgia Power Company Mr. S. E. Kuczynski (w/o enclosures)

Mr. D. G. Bost (w/o enclosures)

Mr. M. D. Meier (w/o enclosures)

Mr. D. H. Jones (w/o enclosures)

Mr. J. B. Klecha Mr. G. Chick Mr. D. L. McKinney (w/o enclosures)

Mr. T. W. Yelverton (w/o enclosures)

Mr. B. H. Whitley Ms. C. A. Gayheart Mr. C. R. Pierce Ms. A. G. Aughtman Mr. D. L. Fulton T

Mr. M. J. Yox Mr. C. T. Defnall Mr. J. Tupik Mr. W. A. Sparkman Ms. A. C. Chamberlain Mr. S. Leighty Mr. E. Riffle Ms. K. Roberts Mr. J. Haswell AF R

Mr. J. Andrews Document Services RTYPE: VND.LI.L00 File AR.01.02.06 Nuclear Regulatory Commission D

Mr. W. Jones (w/o enclosures)

Ms. J. Dixon-Herrity Mr. C. Patel Ms. J. M. Heisserer Mr. B. Kemker Mr. G. Khouri Ms. S. Temple Mr. F. Brown Mr. C. J. Even Mr. A. Lerch Mr. S. Walker

U.S. Nuclear Regulatory Commission ND-19-0670 Page 4 of 4 State of Georgia Mr. R. Dunn Oglethorpe Power Corporation Mr. M. W. Price Ms. A. Whaley Municipal Electric Authority of Georgia Mr. J. E. Fuller Mr. S. M. Jackson Dalton Utilities T

Mr. T. Bundros AF Westinghouse Electric Company, LLC Mr. L. Oriani (w/o enclosures)

T. Rubenstein (w/o enclosures)

Mr. M. Corletti Mr. D. Hawkins Mr. J. Coward Other R

Mr. M. L. Clyde D

Mr. S. W. Kline, Bechtel Power Corporation Ms. L. A. Matis, Tetra Tech NUS, Inc.

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

Mr. S. Roetger, Georgia Public Service Commission Ms. S. W. Kernizan, Georgia Public Service Commission Mr. K. C. Greene, Troutman Sanders Mr. S. Blanton, Balch Bingham NDDocumentinBox@duke-energy.com, Duke Energy Mr. S. Franzone, Florida Power & Light

Southern Nuclear Operating Company ND-19-0670 Enclosure 1 T

AF Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Request for License Amendment:

Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification R (LAR-19-XXX)

D (This Enclosure consists of 14 pages, including this cover page)

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX)

Table of Contents

1.

SUMMARY

DESCRIPTION

2. DETAILED DESCRIPTION 2.1 System Design and Operation 2.2 Current Licensing Basis Requirements 2.3 Reason for the Proposed Change 2.4 Description of the Proposed Change

3. TECHNICAL EVALUATION 3.1 T

Pressurizer Surge Line Analysis and Design 4.

3.2 3.3 3.4 AF Inspections, Tests, Analyses and Acceptance Criteria (ITAAC) and ASME Code III Compliance Permanent Plant Pressurizer Surge Line Instrumentation Summary REGULATORY EVALUATION 4.1 4.2 4.3 RApplicable Regulatory Requirements/Criteria Precedent No Significant Hazards Consideration Analysis D

5.

6.

4.4 Conclusions ENVIRONMENTAL CONSIDERATION REFERENCES Page 2 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX)

1.

SUMMARY

DESCRIPTION Pursuant to 10 CFR 52.98(c) and in accordance with 10 CFR 50.90, Southern Nuclear Operating Company (SNC, or the Licensee) hereby requests an amendment to Combined License (COL)

Nos. NPF-91 and NPF-92 for Vogtle Electric Generating Plant (VEGP) Units 3 and 4, respectively.

Specifically, the requested amendment would eliminate COL condition 2.D.(2)(a)1 which describes a first plant Pressurizer Surge Line Stratification Evaluation and make related revisions to the Updated Final Safety Analysis Report (UFSAR) Tier 2 information. Because this change would modify the COL, this amendment request requires prior Nuclear Regulatory Commission (NRC) approval.

2. DETAILED DESCRIPTION 2.1 System Design and Operation T

The AP1000 pressurizer surge line is an eighteen inch line that connects the top of the Reactor Coolant System (RCS) hot leg 1 to the bottom of the pressurizer. The surge line is designed to accommodate thermal expansion and equipment movement. As such, it is designed with smooth pipe bends rather than fittings and is designed to slope continuously downward to the hot leg without horizontal segments in order to minimize thermal stratification. The design of AF the pressurizer vessel accounts for the possibility of thermal stratification in the pressurizer during normal power operation and for the possibility of insurges and outsurges.

The pressurizer surge line layout provides for adequate flexibility to accommodate thermal expansion as well as equipment movement when the line is at full operating temperature. The pressurizer piping and loop arrangement is designed for flexibility with a fixed vessel and a free floating steam generator/reactor coolant pump support system. The reactor coolant loop and surge line piping are designed to leak-before-break (LBB) criteria.

R There are three permanently installed, nonsafety-related, strap-on resistance temperature detectors (RTDs) located on the RCS pressurizer surge line. These instruments continuously monitor the pressurizer surge line fluid temperature during plant normal operations in order to detect thermal stratification in the surge line. Two of the RTDs are located on a moderately sloped run approximately midway between the RCS hot leg and the pressurizer. One detector D is located on the bottom of the pipe and the other detector on the top. The third detector is located on the pressurizer surge line as close to the pressurizer nozzle as possible. This detector is used to monitor cold insurges to the pressurizer during transient operations.

Temperature indication is provided in the main control room. One low temperature alarm is provided to alert the operator of thermal stratification in the surge line. This alarm is associated with the detector on the bottom of the pipe. During heat up and cooldown operations, a differential temperature alarm indicates significant thermal stratification using the difference between the temperatures measured at the top and bottom of the pipe.

As part of the AP1000 plant conformance to NRC Bulletin 88-11, a monitoring program has been implemented for the first AP1000 plant (i.e., Sanmen Unit 1, China) to record temperature distributions and thermal displacements of the surge line piping during hot functional testing and during the first fuel cycle. The first AP1000 unit used temporary pressurizer surge line instrumentation for monitoring the thermal stratification of the pipeline Page 3 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX) and the displacement of the surge line during hot functional testing and during the plants first fuel cycle. This information is being used to validate assumptions and design inputs used in surge line fatigue analyses.

2.2 Current Licensing Basis Requirements NRC Bulletin 88-11 was issued after Portland Electric Generating Company observed unexpected movement of the pressurizer surge line of the Trojan plant during inspections performed at each refueling outage since they began monitoring surge line movements in 1982. The investigation concluded that movement of piping was caused by thermal stratification in the line. Thermal stratification may occur in piping when flow rates are low and adequate mixing of hot and cold fluid layers does not occur. Thermal stratification in stagnant or slowly flowing lines can result in thermal fatigue in a pipe. NRC Bulletin 88-11 requested that all operating license and construction permit holders at PWRs establish and implement a program to confirm pressurizer surge line integrity in view of the occurrence of thermal stratification, and required addresses to inform the NRC staff of actions taken to resolve this issue.

T UFSAR Section 3.9.3.1.2 discusses the AP1000 conformance to NRC Bulletin 88-11. Request 2.c) of Bulletin 88-11 requests that applicants either monitor the surge line for the effects of thermal stratification beginning with hot functional testing, or obtain data through collective AF efforts to assess the extent of thermal stratification, thermal striping and piping displacements. The AP1000 conformance statement describes the Westinghouse Owners Group program on surge line thermal stratification and surge line data collected from the industry. The AP1000 conformance statement also commits to monitoring the surge line during hot functional testing and during the first cycle of the first AP1000 plant. It points to the commitment in UFSAR Subsection 3.9.8.5 to perform the monitoring.

COL Section 2.D.(2)(a)1. requires that a Pressurizer Surge Line Stratification Evaluation (first plant test as identified in UFSAR Section 14.2.9.1.7 item (d)) be performed by SNC. UFSAR R

Section 14.2.9.1.7 item (d) describes the monitoring program that will be performed and directs readers to USFAR Section 3.9.3. Additionally, there is discussion of the commitment to perform the Pressurizer Surge Line Testing for the first plant only in UFSAR Section 14.2.9.2.22.

2.3 Reason for the Proposed Change D Pressurizer surge line monitoring is required at the first AP1000 unit, as described in UFSAR subsections 3.9.3.1.2 and 14.2.9.1.7 item (d). This monitoring does not need to be performed at Vogtle Units 3 and 4. The AP1000 plant, as described in the UFSAR, has been designed to limit thermal stratification in the pressurizer surge line in accordance with NRC Bulletin 88-

11. First plant data has been collected and will be used to verify the inputs used in the pressurizer surge line design analysis, which will be included as part of the as-built reconciliation of the reactor coolant system ASME Section III Piping System. Even though the Sanmen Unit 1 data is sufficient to perform the verification of the AP1000 surge line design analysis inputs, the permanent plant RTDs in Vogtle Unit 3 & 4 surge line and the data recorded from these RTDs can be used to confirm the surge line is operating as expected.

Therefore, it is not necessary to collect additional pressurizer surge line data at Vogtle Unit 3 and 4.

Page 4 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX) 2.4 Description of the Proposed Change Pressurizer surge line monitoring is required at the first AP1000 unit, as described in UFSAR subsections 3.9.3.1.2 and 14.2.9.1.7 item (d). The monitoring, as described in the Vogtle 3 and 4 UFSAR Subsections 3.9.3 and 14.2.5, is part of conformance to Bulleting 88-11. The proposed changes would revise the conformance descriptions to Bulletin 88-11 to remove the requirement to monitor the pressurizer surge line. Similarly, COL condition 2.D.(2)(a)1.,

Pressurizer Surge Line Stratification Evaluation, will be removed from the list of Pre-operational Testing activities.

3. TECHNICAL EVALUATION Thermal stratification, cycling and striping are phenomena that have resulted in pipe cracking at nuclear power plants. As a result of these incidents, the United States Nuclear Regulatory Commission has issued several bulletins, including NRC Bulletin 88-08, Thermal Stresses in Piping Connected to Reactor Coolant Systems, and NRC Bulletin 88-11, Pressurizer Surge Line Thermal Stratification.

T Thermal stratification may occur in piping when flow rates are low and adequate mixing of hot and cold fluid layers does not occur. Thermal cycling due to stratification may occur because AF of leaking valves or plant operation. Thermal striping is a cyclic mechanism caused by instabilities in the hot-cold fluid interface in stratified fluid during relatively steady flow conditions. The design of piping and component nozzles in the AP1000 design includes provisions to minimize the potential for and the effects of thermal stratification and cycling.

Likewise, piping and component supports have been designed and evaluated for the thermal expansion of the piping resulting from potential stratification modes. The AP1000 plant pressurizer surge line design included consideration of the information on thermal cycling and thermal stratification described in NRC Bulletins 79-13, 88-08, and 88-11, and other applicable design standards.

R The pressurizer surge line is constructed to ASME Code Section III requirements, has leak-before-break capabilities and the functional capability is demonstrated by ITAAC. Additionally, there are three permanently installed nonsafety-related RTDs located on the RCS pressurizer surge line. These instruments monitor the pressurizer surge line fluid temperature to detect D thermal stratification in the surge line. Lastly, the first AP1000 plant (Sanmen Unit 1) monitored the temperature in the pressurizer surge line using temporary RTDs and displacement sensors, as well as, the three permanent plant RTDs during hot functional testing and the first fuel cycle. The steady state displacement and temperature measurements of the surge line at different plateaus during hot functional testing heat up and cooldown have met acceptance criteria. The data collected at Sanmen Unit 1 is representative of the data that would be collected at Vogtle Units 3 and 4 with first-cycle temporary instrumentation. Because Sanmen Unit 1 and Vogtle 3 and 4 are both using the standard AP1000 design for the pressurizer surge line, it is unlikely that additional insight into the temperature stratification phenomena will be gained by collecting more data at Vogtle Unit 3 and 4.

Page 5 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX) 3.1 Pressurizer Surge Line Analysis and Design The proposed change to remove the requirement to thermally monitor the AP1000 pressurizer surge line during hot functional testing and the first operating cycle does not impact the ability of the surge line to perform its safety-related design function, as described in the UFSAR.

UFSAR Section 5.4.3.3 describes how the pressurizer surge line has been designed and instrumented to minimize the potential for thermal stratification and how it is monitored to provide indication to the operators of the temperatures in the surge line. Three locations are monitored with permanent plant equipment (strap-on RTDs). The change to remove the requirement for temporary instrumentation does not impact the permanent plant instrumentation or the requirement that the temperature in the surge line be monitored by plant operators.

UFSAR Section 3.9.3.1.2 describes how the AP1000 plant conforms with NRC Bulletin 88-11, sections 2.a) through 2.d). Conformance with each of the requests in the Bulletin continues to be achieved without performing additional thermal monitoring of the surge line at Vogtle Unit T

3 and 4. As described below, each of the Bulletin requests are listed, along with the current UFSAR AP1000 conformance statement, and an additional discussion of how the request continues to be satisfied.

AF NRC Bulletin 88-11 Requirement 2.a):

Before issuance of the low power license, applicants are requested to demonstrate that the pressurizer surge line meets the applicable design codes and other FSAR and regulatory commitments for the licensed life of the plant. This may be accomplished by performing a plant specific or generic bounding analysis. The analysis should include consideration of thermal stratification and thermal striping to ensure that fatigue and stresses are in compliance with applicable code limits. The analysis and hot functional testing should verify that piping thermal deflections result in no adverse consequences, such as contacting the pipe whip R

restraints. If analysis or test results show Code noncompliance, conduct of all actions specified below is requested.

UFSAR AP1000 Conformance Statement for Requirement 2.a): Analysis of the AP1000 surge line considers thermal stratification and thermal striping, and demonstrates that the surge line meets applicable code requirements for the licensed life of the plant. Hot functional testing D requirements for the AP1000 ensure that piping thermal deflections result in no adverse consequences.

Design Discussion for Requirement 2.a): AP1000 design conformance with this requirement continues to be satisfied. The design and function of the surge line are not impacted by this change. A three-dimensional computational fluid dynamics model of the AP1000 pressurizer surge line was performed in order to determine the stratification profiles for the AP1000 pressurizer surge line used in the design analyses. In addition, the AP1000 pressurizer surge line piping stress analysis, including a fatigue analysis, evaluated the pressurizer surge line components according to the Class 1 design analysis requirements of the Section III ASME B&PV Code, 1998 Edition and 2000 Addenda.

NRC Bulletin 88-11 Requirement 2.b):

Applicants are requested to evaluate operational alternatives or piping modifications needed to reduce fatigue and stresses to acceptable levels.

Page 6 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX)

UFSAR AP1000 Conformance Statement for Requirement 2.b):

Analysis of the AP1000 surge line confirmed that stress and fatigue requirements are satisfied, therefore the evaluation of operational alternatives or piping modifications was not required.

Design Discussion for Requirement 2.b):

Removal of the requirement to thermally monitor the AP1000 pressurizer surge line during hot functional testing and the first cycle of operation using temporary monitoring instrumentation does not impact the design of the pressurizer surge line. The AP1000 pressurizer surge line is designed to accommodate thermal expansion and equipment moment. During conditions with the greatest potential for thermal stratification, the pressurizer heaters and spray valves may be operated to maintain a continuous outflow of water to minimize the severity of stratification and the possibility of pressurizer thermal transients resulting from insurges. The permanent strap on RTDs will continue to perform their design function, monitoring the surge line temperatures and alerting the operators in the event of temperature measurements that NRC Bulletin 88-11 Requirement 2.c): T may indicate thermal stratification in the pressure surge line.

Applicants are requested to either monitor the surge line for the effects of thermal stratification, AF beginning with hot functional testing, or obtain data through collective efforts to assess the extent of thermal stratification, thermal striping and piping displacements.

UFSAR AP1000 Conformance Statement for Requirement 2.c):

As part of the Westinghouse Owners Group program on surge line thermal stratification, Westinghouse collected surge line physical design and plant operational data for all domestic Westinghouse PWRs. In addition, Westinghouse collected surge line monitoring data from approximately 30 plants. This experience was used in the development of the AP1000 thermal R

stratification loading calculations. As described in the AP1000 Conformance to Request 3 of Bulletin 88-11, monitoring will be performed during hot functional testing and during the first cycle of the first AP1000 plant. This Combined License item is identified in Subsection 3.9.8.5.

Subsequent monitoring of the AP1000 surge line is not required.

D Design Discussion for Requirement 2.c):

As a part of the AP1000 plant conformance to NRC Bulletin 88-11, a monitoring program was required to be implemented at the first AP1000 unit to record temperature distributions and thermal displacement of the surge line during hot functional testing and the first fuel cycle.

The first AP1000 plant, Sanmen Unit 1, monitored the temperature in the pressurizer surge line using temporary RTDs and displacement sensors, as well as, the three permanent plant RTDs during hot functional testing and the first fuel cycle. The steady state displacement and temperature measurements of the surge line at different plateaus during hot functional testing heat up and cooldown met the acceptance criteria as evaluated by Westinghouse.

NRC Bulletin 88-11 Requirement 2.d):

Applicants are requested to update stress and fatigue analyses, as necessary, to ensure Code compliance. The analyses should be completed no later than one year after issuance of the low power license.

Page 7 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX)

UFSAR AP1000 Conformance Statement for Requirement 2.d):

Revision of the stress and fatigue analyses is not required for the AP1000 surge line, since the design analysis considers thermal stratification and thermal striping.

Design Discussion for Requirement 2.d):

The thermal monitoring data collected from the first operating plant, Sanmen Unit 1, will be used to verify the inputs used in the pressurizer surge line design analysis. The data collected is representative of the data that would be collected at Vogtle Unit 3 and 4 with first-cycle temporary instrumentation. It is unlikely that any additional insight into the temperature stratification phenomena will be gained by collecting additional data at Vogtle Unit 3 and 4.

The evaluation of the data from the first operating plant will be included as a part of the as-built reconciliation of the RCS ASME Section III piping system, as described in UFSAR Section 3.9.

Summary:

T The design and functionality of the AP1000 pressurizer surge line is not impacted by this change. The change does not impact any permanent plant equipment. The AP1000 plant continues to conform to the requirements of NRC Bulletin 88-11. The COL and UFSAR AF requirements are to perform thermal monitoring of the pressurizer surge line during hot functional testing and the first operating cycle. This monitoring was performed at Sanmen Unit 1 and does not need to be re-performed at Vogtle Unit 3 and 4. The data collected at Sanmen Unit 1 is representative of the data that would be collected at Vogtle Unit 3 and 4 with first-cycle temporary instrumentation, and it is unlikely that any additional insight into the temperature stratification phenomena would be gained by collection of additional data at Vogtle Unit 3 and 4. Removal of the monitoring requirement is not an adverse change to the AP1000 design.

R 3.2 Inspections, Tests, Analyses and Acceptance Criteria (ITAAC) and ASME Code III Compliance The pressurizer surge line is identified in Table 2.1.2-2 of Appendix C of the Vogtle 3 and 4 COLs. One of the design commitments associated with the pressurizer surge line is described D in ITAAC 2.1.02.02a (Index No. 13), which states: [t]he piping identified in Table 2.1.2-2 as ASME Code Section III is designed and constructed in accordance with ASME Code Section III requirements. This ITAAC also has a design commitment that each of the as-built lines identified in Table 2.1.2-2 designated as LBB must meet the LBB criteria.

These ITAAC confirm and demonstrate that the as-built pressurizer surge line is correctly built and tested and that the design commitment for a mechanistic pipe break (LBB) evaluation of high-energy piping systems is completed. The use of mechanistic pipe break criteria represents a higher level of confidence of the integrity of piping systems based on additional criteria compared to the existing high level of integrity provided by the requirements of the ASME Code.

Design specifications and design reports for ASME Section III piping are made available for NRC review. Reconciliation of the as-built piping (verification of the thermal cycling and stratification loading) is completed after the construction of the piping systems and prior to fuel load.

Page 8 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX) 3.3 Permanent Plant Pressurizer Surge Line Instrumentation There are three permanently installed nonsafety-related RTDs located on the RCS pressurizer surge line. These instruments continuously monitor the pressurizer surge line fluid temperature during plant normal operations in order to detect thermal stratification in the surge line. Two of the RTDs are located on a moderately sloped run approximately midway between the RCS hot leg and the pressurizer. One RTD is located on the bottom of the pipe and the other RTD on the top. The third RTD is located on the pressurizer surge line as close to the pressurizer nozzle as possible. This detector is used to monitor cold insurges to the pressurizer during transient operations.

The RTD temperature indication is provided in the main control room. One low temperature alarm is provided to alert the operator of thermal stratification in the surge line. This alarm is associated with the RTD on the bottom of the pipe. During heatup and cooldown operations, a differential temperature alarm indicates significant thermal stratification using the difference between the temperatures measured at the top and bottom of the pipe.

3.4 Summary T

In summary, the design and functionality of the pressurizer surge line is not impacted by this AF change because no design changes are proposed to any SSC. Vogtle Units 3 and 4 continue to conform to the requirements of NRC Bulletin 88-11. The COL and UFSAR requirements are to perform thermal monitoring of the pressurizer surge line at the first AP1000 unit during hot functional testing and the first operating cycle.

The first plant Pressurizer Surge Line Stratification Evaluation testing is unnecessary at Vogtle Units 3 and 4 because: the AP1000 plant was designed to account for thermal cycling and stratification and includes extensive industry operating experience; surge line piping is designed to ASME III and leak-before-break criteria that is confirmed through ITAAC; R

permanently installed RTDs located on the surge line monitor the fluid temperature to detect thermal stratification; and, because the data collected at Sanmen Unit 1 is representative of the AP1000 standard design and it is unlikely that additional insight into the temperature stratification phenomena will be gained by collecting additional data at Vogtle Units 3 or 4.

Therefore, removal of the monitoring requirement is not an adverse change to the AP1000 D design.

4. REGULATORY EVALUATION 4.1 Applicable Regulatory Requirements/Criteria 10 CFR Part 52.98(c) requires an amendment to the license for any modification to, addition to, or deletion from the terms and conditions of a combined license, including modification to, addition to, or deletion from the inspections, tests, analyses, or related acceptance criteria contained in the license. This change involves changes to UFSAR Subsections 14.2.5, 14.2.9.1.7, 14.2.9.2.22 and requires a revision to COL condition 2.D.(2)(a)1.

Therefore, a license amendment request (LAR) (as supplied herein) is required.

10 CFR Part 50, Appendix A, General Design Criterion (GDC) Criterion 1Quality standards and records, requires that structures, systems, and components (SSCs) important to safety be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety functions to be performed. The proposed Page 9 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX) changes do not alter the design, fabrication or first plant testing of SSCs that are important to safety. Therefore, the proposed changes comply with the requirements of GDC 1.

10 CFR Part 50, Appendix A, GDC Criterion 2Design bases for protection against natural phenomena, requires that structures, systems and components important to safety be designed to withstand the effects of natural phenomena, such as earthquakes. The proposed change to remove the requirement to monitor the pressurizer surge line for thermal stratification and thermal cycling during hot functional testing and during the first fuel cycle for the first plant only does not impact the existing seismic design requirements for the RCS, including seismic Category I requirements. The proposed change does not involve physical modifications or addition of systems, structures, and components, and does not impact the existing seismic design requirements. Therefore, the proposed changes comply with the requirements of GDC 2.

10 CFR Part 50, Appendix A, GDC Criterion 4Environmental and dynamic effects design bases,requires that systems, structures, and components can withstand the dynamic effects associated with missiles, pipe whipping, and discharging fluids, excluding dynamic effects T

associated with pipe ruptures, the probability of which is extremely low under conditions consistent with the design basis for the piping. The proposed change to remove the requirement to monitor the pressurizer surge line for thermal stratification and thermal cycling during hot functional testing and during the first fuel cycle for the first plant only AF proposed changes do not impact the existing design requirements for the RCS. The proposed changes do not involve physical modifications or addition of systems, structures, and components, and do not impact the existing capability of the RCS to withstand dynamic effects associated with missiles, pipe whipping, and discharging fluids as required by this criterion. Therefore, the proposed changes comply with the requirements of GDC 4.

10 CFR Part 50, Appendix A, GDC Criterion 14Reactor coolant pressure boundary, requires that the reactor coolant pressure boundary be designed, fabricated, erected, and tested so as to have an extremely low probability of abnormal leakage, of rapidly propagating failure, and of gross rupture. The proposed change to remove the requirement R

to monitor of the pressurizer surge line for thermal stratification and thermal cycling during hot functional testing and during the first fuel cycle for the first plant only, do not impact the existing design requirements for the RCS. The proposed change does not involve physical modifications or addition of systems, structures, and components, and does not impact the existing capability of the pressurizer surge line to perform the required reactor coolant D pressure boundary functions. Therefore, the proposed changes comply with the requirements of GDC 14.

10 CFR Part 50, Appendix A, GDC Criterion 15Reactor coolant system design,requires that the reactor coolant system and associated auxiliary, control, and protection systems shall be designed with sufficient margin to assure that the design conditions of the reactor coolant pressure boundary are not exceeded during any condition of normal operation, including anticipated operational occurrences. The proposed change to remove the requirement to install temporary instrumentation on the pressurizer surge line for thermal stratification and thermal cycling during hot functional testing and during the first fuel cycle for the first plant only, do not impact the existing design requirements for the RCS. The proposed change does not involve physical modifications or addition of systems, structures, and components, does not impact the existing capability of the pressurizer surge line to perform the required reactor coolant pressure boundary functions, and does not impact the existing auxiliary, control, and protection systems. The proposed changes do not impact Page 10 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX) permanent plant instrumentation necessary for monitoring and control of the RCS.

Therefore, the proposed changes comply with the requirements of GDC 15 Regulatory Guide (RG) 1.68, Initial Test Programs for Water-Cooled Nuclear Power Plants, Revision 2 describes the Initial Test Program (ITP) requirements. The proposed changes to the Pressurizer Surge Line Stratification Evaluation first plant tests do not alter compliance with RG 1.68 and the SSCs within the scope of RG 1.68 are still included in the ITP. The proposed changes to the Pressurizer Surge Line Stratification Evaluation first plant tests do not adversely impact the UFSAR in terms of conformance to RG 1.68.

The proposed changes have been evaluated to determine whether applicable regulations continue to be met. It was determined that the proposed changes do not affect conformance with the applicable regulatory requirement, Regulatory Guides or General Design Criteria differently than as described in the plant-specific DCD or UFSAR.

4.2 Precedent 4.3 No precedent was identified.

No Significant Hazards Consideration Analysis T

The requested amendment involves changes to eliminate the performance of the AF Pressurizer Surge Line Stratification Evaluation first plant test at VEGP Units 3 and 4, by revising the COLs and UFSAR Subsections 14.2.5, 14.2.9.1.7 and 14.2.9.2.22.

The first plant Pressurizer Surge Line Stratification Evaluation testing is unnecessary at Vogtle Units 3 and 4 because: the AP1000 plant was designed to account for thermal cycling and stratification; surge line piping is designed to ASME III and leak-before-break criteria that is confirmed through ITAAC; permanently installed RTDs located on the surge line monitor the fluid temperature to detect thermal stratification; and, because the data collected at Sanmen Unit 1 is representative of the AP1000 design and it is unlikely that additional R

insight into the temperature stratification phenomena will be gained by collecting more data at Vogtle Units 3 or 4.

An evaluation to determine whether or not a significant hazards consideration is involved with the proposed amendment was completed by focusing on the three standards set forth D

4.3.1 in 10 CFR 50.92, Issuance of Amendment, as discussed below.

Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No The proposed change does not affect the operation of any systems or equipment that initiates an analyzed accident or alter any structures, systems, or components accident initiator or initiating sequence of events. The proposed changes remove the requirement to perform the Pressurizer Surge Line Stratification Evaluation first plant tests based on a number of factors that render the testing unnecessary. The changes do not adversely affect any methodology which would increase the probability or consequences of a previously evaluated accident.

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ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX)

The change does not impact the support, design, or operation of mechanical or fluid systems. There is no change to plant systems or the response of systems to postulated accident conditions. There is no change to predicted radioactive releases due to normal operation or postulated accident conditions. The plant response to previously evaluated accidents or external events is not adversely affected, nor does the proposed change create any new accident precursors.

The proposed changes do not involve a change to any mitigation sequence or the predicted radiological releases due to postulated accident conditions, thus, the consequences of the accidents evaluated in the UFSAR are not affected.

Therefore, the proposed amendment does not involve a significant increase in the probability or consequences of a previously evaluated accident.

4.3.2 Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No T

The proposed changes remove the requirement to perform the Pressurizer Surge Line Stratification Evaluation first plant tests based on a number of factors that render the AF testing unnecessary. The proposed changes do not adversely affect any design function of any SSC design functions or methods of operation in a manner that results in a new failure mode, malfunction, or sequence of events that affect safety-related or non-safety-related equipment. This proposed change does not allow for a new fission product release path, result in a new fission product barrier failure mode, or create a new sequence of events that result in significant fuel cladding failures.

These proposed changes do not adversely affect any other SSC design functions or methods of operation in a manner that results in a new failure mode, malfunction, or R

sequence of events that affect safety-related or nonsafety-related equipment. Therefore, this proposed change does not allow for a new fission product release path, result in a new fission product barrier failure mode, or create a new sequence of events that results in significant fuel cladding failures.

D 4.3.3 Therefore, the proposed amendment does not create the possibility of a new or different kind of accident from any accident previously evaluated.

Does the proposed amendment involve a significant reduction in a margin of safety?

Response: No The proposed change maintains existing safety margin and provides adequate protection through continued application of the existing requirements in the UFSAR. The proposed change satisfies the same design functions in accordance with the same codes and standards as stated in the UFSAR. This change does not adversely affect any design code, function, design analysis, safety analysis input or result, or design/safety margin.

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ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX)

No safety analysis or design basis acceptance limit/criterion is challenged or exceeded by the proposed change.

No safety analysis or design basis acceptance limit/criterion is challenged or exceeded by this change, and no significant margin of safety is reduced.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above, it is concluded that the proposed amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of no significant hazards consideration is justified.

4.4 Conclusions This assessment addresses the considerations discussed above. The plant licensing basis, T

safety analyses, and design bases evaluations demonstrate that the requested change is accommodated without an increase in the probability or consequences of an accident previously evaluated, without creating the possibility of a new or different kind of accident from any accident previously evaluated, and without a significant reduction in the margin of AF safety. In conclusion, based on the considerations discussed above, (1) there is a reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public. Having arrived at negative declarations with regard to the criteria of 10 CFR 50.92, this assessment determined that the requested change does not involve a Significant Hazards Consideration.

R

5. ENVIRONMENTAL CONSIDERATIONS This review supports a request to amend the Combined License (COL) to revise the element of the certification information related to Pressurizer Surge Line Stratification Evaluation first plant tests requirements in Updated Final Safety Analysis Report (UFSAR) and COL Condition D

2.D.(2)(a)1.

Sections 2 and 3 of this license amendment request provide the details of the proposed change.

The Licensee has determined that the anticipated construction and operational effects of the proposed amendment meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9), in that:

(i) There is no significant hazards consideration.

As documented in Section 4.3, Significant Hazards Consideration, of this license amendment request, an evaluation was completed to determine whether or not a significant hazards consideration is involved by focusing on the three standards set forth in 10 CFR 50.92, Issuance of Amendment. The significant hazards consideration determined that (1) the requested amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated; (2) the requested amendment does not create the possibility of a new or different kind of accident from any accident previously Page 13 of 14

ND-19-0670 Elimination of License Condition to Evaluate Pressurizer Surge Line Stratification (LAR-19-XXX) evaluated; and (3) the requested amendment does not involve a significant reduction in a margin of safety. Therefore, it is concluded that the requested amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and accordingly, a finding of no significant hazards consideration is justified.

(ii) There is no significant change in the types or significant increase in the amounts of any effluents that may be released offsite.

The proposed change is unrelated to any aspect of plant construction or operation that would introduce any change to effluent type (e.g., effluents containing chemicals or biocides, sanitary systems effluents, and other effluents), or affect any plant radiological or non-radiological effluent release quantities. Furthermore, the proposed changes do not affect any effluent release path or diminish the design function or operational features that are credited with controlling the release of effluents during plant operation. Therefore, it is concluded that the requested amendment does not involve a significant change in the types or a significant increase on the amounts of any effluents that may be released offsite.

(iii)

T There is no significant increase in individual or cumulative occupational radiation exposure.

The proposed changes do not adversely affect walls, floors, or other structures that provide shielding. Plant radiation zones are not affected, and there are no changes to the controls required under 10 CFR Part 20 that preclude a significant increase in occupational radiation AF exposure. Therefore, the requested amendment does not involve a significant increase in individual or cumulative occupational radiation exposure.

Based on the above review of the requested amendment, it has been determined that the anticipated construction and operational impacts of the requested amendment do not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, and (iii) a significant increase in the individual or cumulative occupational radiation exposure. Accordingly, the requested amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, R

pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection the requested amendment.

6. REFERENCES D

None.

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Southern Nuclear Operating Company ND-19-0670 T

Enclosure 2 AF Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Proposed Changes to Licensing Basis Documents R (LAR-19-XXX)

D Note:

Added text is shown as Blue Underline Deleted text is shown as Red Strikethrough

• Omitted text is shown as three asterisks (*...*...*)

(This Enclosure consists of 4 pages, including this cover page)

ND-19-0670 Proposed Changes to Licensing Basis Documents (LAR-19-XXX)

COL Changes Combined License Condition 2.D.(2)(a)1, Pre-operational Testing - revise as shown below:

(2) Pre-operational Testing (a) SNC shall perform the design-specific pre-operational tests identified below:

1. Pressurizer Surge Line Stratification Evaluation (first plant test as identified in UFSAR, Section 14.2.9.1.7 Item (d));

2. Automatic Depressurization System Blowdown Test (first three plants test as identified in UFSAR Section 14.2.9.1.3 Item (s)).

UFSAR Changes Component Supports

T UFSAR Subsection 3.9.3.1.2, Loads for Class 1 Components, Core Support, and AF A monitoring program will be implemented as discussed in Subsection 3.9.8.5 at the first AP1000 to record temperature distributions and thermal displacements of the surge line piping, as well as pertinent plant parameters such as pressurizer temperature and level, hot leg temperature, and reactor coolant pump status. Monitoring will be performed during hot functional testing and during the first fuel cycle. The resulting monitoring data will be evaluated to show that it is within the bounds of the analytical temperature distributions and displacements.

General R

PRESSURIZER SURGE LINE MONITORING The pressurizer surge line is monitored at the first AP1000 plant to record temperature distributions and thermal displacements of the surge line piping, as well as pertinent plant D

parameters. This monitoring occurs during the hot functional testing and first fuel cycle. The resulting monitoring data is evaluated to verify that the pressurizer surge line is within the bounds of the analytical temperature distributions and displacements.

Subsequent AP1000 plants (after the first AP1000 plant) confirm that the heatup and cooldown procedures are consistent with the pertinent attributes of the first AP1000 plant surge line monitoring. In addition, changes to the heatup and cooldown procedures consider the potential impact on stress and fatigue analyses consistent with the concerns of NRC Bulletin 88-11.

The pressurizer surge line monitoring activities include the following methodology and requirements:

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ND-19-0670 Proposed Changes to Licensing Basis Documents (LAR-19-XXX)

Monitoring Method The pressurizer surge line pipe wall is instrumented with outside mounted temperature and displacement sensors. The data from this instrumentation is supplemented by plant computer data from related process and control parameters.

Locations to be Monitored In addition to the existing permanent plant temperature instrumentation, temperature and displacement monitoring will be included at critical locations on the surge line. The additional locations utilized for monitoring during the hot functional testing and the first fuel cycle (see Subsection 14.2.9.2.22) are selected based on the capability to provide effective monitoring.

Data Evaluation Data evaluation is performed at the completion of the monitoring period (one fuel cycle). The T

evaluation includes a comparison of the data evaluation results with the thermal profiles and transient loadings defined for the pressurizer surge line, accounting for expected pipe outside wall temperatures. Interim evaluations of the data are performed during the hot functional testing period, up to the start of normal power operation, and again once three months worth of AF normal operating data has been collected, to identify any unexpected conditions in the pressurizer surge line.

UFSAR Subsection 14.2.5, Utilization of Reactor Operating and Testing Experience in the Development of Initial Test Program, revise text as shown below:

Pressurizer Surge Line Stratification Evaluation (14.2.9.1.7 Item (d))

R This test is not required to be conducted at Vogtle Units 3 and 4. As part of the AP1000 conformance to NRC Bulletin 88-11, a monitoring program will be implemented by the COL Applicant for the first AP1000 to record temperature distributions and thermal displacements of the surge line piping during hot functional testing and during the first fuel cycle, as discussed in Subsection 3.9.3.

D UFSAR Subsection 14.2.9.1.7, Expansion, Vibration and Dynamic Effects Testing, revise as shown below:

d) Not used. As described in Subsection 3.9.3, temperature sensors are installed on the pressurizer surge line for monitoring thermal stratification and thermal cycling during power operation. Testing is performed to verify proper operation of these sensors. Note that this verification is required only for the first plant.

14.2.9.2.22 Pressurizer Surge Line Testing (First Plant Only), revise as shown below:

Not used. Purpose Page 3 of 4

ND-19-0670 Proposed Changes to Licensing Basis Documents (LAR-19-XXX)

The purpose of the pressurizer surge line testing is: a) to obtain data to verify the proper operation of temperature sensors installed on the pressurizer surge line, and b) to obtain pressurizer surge line piping displacement and thermal stratification measurements, as described in Subsections 3.9.3, 14.2.5, and 14.2.9.1.7 item (d).

Prerequisites The component tests for the individual components associated with the Reactor Coolant System have been completed. The testing and calibration of the required test instrumentation has been completed. The temporary sensors and instrumentation lead wires required for monitoring thermal stratification, cycling, and striping have been installed. The calibration of the transducers and the operability of the data acquisition equipment have been verified. Prior to testing of the piping system, a pretest walk-down shall be performed to verify that the anticipated piping movement is not obstructed by objects not designed to restrain the motion of the system (including instrumentation and branch lines). The system walk-down shall also verify that supports are set in accordance with the design.

General Test Methods and Acceptance Criteria T design specifications.

AF The performance of the pressurizer surge line is observed and recorded during a series of individual tests that characterize the various modes of system operation. This testing verifies that the temperature sensors operate as described in Subsection 3.9.3 and in appropriate a) Verify the proper operation of temperature sensors installed on the pressurizer surge line.

b) Record sensor data at specified intervals throughout hot functional testing of the RCS system, including during the drawing and collapsing of the bubble in the pressurizer.

x R

c) Retain the following plant parameters time history for the same data recording period:

x Hot leg temperature Reactor Coolant System pressure D x x

x x

x x

x x

Reactor coolant pump status Pressurizer level Pressurizer temperature (liquid and steam)

Pressurizer surge line temperatures Pressurizer spray temperature Reactor Coolant System charging flow rate Pressurizer spray and auxiliary spray flow Charging line to auxiliary spray flow (valve position for auxiliary spray on) x Normal residual heat removal system flow rate d) The transducers and associated hardware may be removed after the completion of testing.

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