ULNRC-06779, ULNRC-06779: Contesting of Green NCV 05000483/2022010-03, Failure to Perform Required Inservice Testing of Residual Heat Removal Heat Exchanger Pneumatically (Air) Operated Outlet and Bypass Valves

ULNRC-06779: Contesting of Green NCV 05000483/2022010-03, Failure to Perform Required Inservice Testing of Residual Heat Removal Heat Exchanger Pneumatically (Air) Operated Outlet and Bypass Valves

ML22318A188
Person / Time
Site:	Callaway
Issue date:	11/14/2022
From:	Cox B Ameren Missouri, Union Electric Co
To:	Office of Nuclear Reactor Regulation, Document Control Desk
Shared Package
ML22318A187	List: ML22318A189 ML22318A190 ULNRC-06779, ULNRC-06779: Contesting of Green NCV 05000483/2022010-03, Failure to Perform Required Inservice Testing of Residual Heat Removal Heat Exchanger Pneumatically (Air) Operated Outlet and Bypass Valves
References
ULNRC-06779 IR 2022010-03
Download: ML22318A188 (1)

Text

v!/AI11erefl Callaway Plant MISSOURI November 14, 2022 ULNRC-06779 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Ladies and Gentlemen:

DOCKET NUMBER 50-483 CALLAWAY PLANT UNIT 1 UNION ELECTRIC CO.

RENEWED FACILITY OPERATING LICENSE NPF-30 CONTESTING OF GREEN NCV 05000483/2022010-03, FAILURE TO PERFORM REQUIRED INSERVICE TESTING OF RESIDUAL HEAT REMOVAL HEAT EXCHANGER PNEUMATICALLY (AIR) OPERATED OUTLET AND BYPASS VALVES

References:

1 . Callaway Plant Biennial Problem Identification and Resolution Inspection Report 05000483/2022010 dated October 12, 2022. (ADAMS Accession No. ML22277A822)

By letter dated October 1 2, 2022 (Reference 1 ), the U. S Nuclear Regulatory Commission (NRC) issued Inspection Report 05000483/2022010 providing results of the Biennial Problem Identification and Resolution Inspection conducted at Ameren Missouris Callaway Energy Center from August 15 through September 1, 2022.

In the referenced inspection report, the NRC issued a Green non-cited violation (NCV) of Title 10 CFR 50.55a(f), Preservice and inservice testing requirements, paragraph (4), Inservice testing standards requirements for operating plants, asserting that Callaway had failed to perform required inservice testing in accordance with the ASME OM Code for trains A and B residual heat removal heat exchanger air-operated outlet and bypass valves as a result of incorrectly classifying them as passive valves. The NRC inspection report states that the most significant contributing cause or primary cause ofthe performance deficiency associated with this finding related to the licensees historical understanding ofits design and licensing basis. The inspection report also states that A LOCA or any design basis accident, such as a loss of offsite power, are credible events required to be mitigated in MODE 4 in accordance with the regulatory requirements and the licensees licensing and design basis.

8315 County Road 459 : Steedman, MO 65077  : AmerenMissouri.com

ULNRC-06779 November 14, 2022 Page 2 of 3 Ameren Missouri respectfully disagrees with the identified violation and maintains that the ASME OM Code passive classification for the subject valves is consistent with Callaways design and licensing basis requirements, which fully comply with the regulatory requirements.

The subject valves are maintained in their safety position (i.e., not repositioned) during operational modes that require them to support a plant shutdown to Callaways licensed safe-shutdown condition.

For Callaway, the licensed safe-shutdown condition is Hot Standby (Mode 3). The subject valves are also maintained in their safety position (i.e., not repositioned) during operational modes in which they are required to be capable of mitigating the consequences of Callaways analyzed design basis accident (DBA) loss-of-coolant accident (LOCA). Callaways DBA LOCA analysis ofrecord assumes the plant is operating in Mode 1 (full power), as the bounding condition, but no Mode 4 LOCA analysis of record exists.

Ameren Missouri is concerned that the inspection report position constitutes a new interpretation of Callaways design and licensing basis requirements for LOCA mitigation. This NRC position would require Ameren Missouri to change Callaways licensing and design bases. Due to the absence of regulatory requirements or NRC approved guidance related to performance of a Mode 4 DBA LOCA analysis, it is unclear what analysis and NRC approval would be needed for Callaway to comply with this position.

In summary, Ameren Missouri respectfully disagrees that a violation of regulatory requirements occurred and maintains that Callaway fully complies with Title 10 CFR 50.55a(f), Preservice and inservice testing requirements, paragraph (4), Inservice testing standards requirement for operating plants, for the subject valves. Further, changing the valves ASME OM Code classification to active is inconsistent with Callaways historical and current licensing basis. In addition, there are currently no regulatory requirements for licensees to perform a LOCA analysis in Mode 4.

The enclosures to this letter provide Ameren Missouris detailed response and basis for denying NCV 05000483/2022010-03.

This letter does not contain new commitments.

Ifthere are any questions, please contact Mr. Todd A. Witt at 314-478-5346.

Sincerely, Barry Cox Nuclear Site Vice President

Enclosures:

1. Ameren Missouris Response to NCV 05000483/2022010-03

2. Pressurized Water Reactor Owners Group letter, OG-22-1 87, PWR Owners Group Mode 4 LOCA Analysis for Westinghouse NSSS Plants, dated October 27, 2022.

ULNRC-06779 November 14, 2022 Page 3 of 3 cc: Mr. Scott A. Morris: Regional Administrator NRC Region IV Dan Bradley: Senior Resident Inspector Mr. Mahesh Chawla: Project Manager, Callaway Plant Mark Lombard: Director, Office of Enforcement Certrec Corporation (Receives ALL attachments as long as they are non-safeguards and may be publicly disclosed.)

F. M. Diya B. L. Cox F. I. Bianco D. E. Farnsworth T. A. Witt T. B. Elwood NSRB Secretary STARS Regulatory Affairs Mr. Jay Silberg (Pillsbury Winthrop Shaw Pittman LLP)

Index and send hardcopy to QA File A160.0761