ML22222A111

2022 Kmkt Fort Calhoun Flood Finding and 2011 Missouri River Flooding Reduce

ML22222A111
Person / Time
Site:	Fort Calhoun
Issue date:	07/28/2022
From:	Gerond George NRC Region 4
To:	NRC/NRR/DRO/IRAB
Kenneth Kolaczyk, NRR/DRO/IRAB, 58577389
Shared Package
ML22222A099	List: ML22222A109 ML22222A110 ML22222A111 ML22222A112
References
Download: ML22222A111 (42)

Text

Fort Calhoun Station Yellow Flood Finding and 2011 Missouri River Flood Response

By Gerond A. George Senior Reactor Inspector NRC Region IV DISCLAIMER

This training session is being recorded for future use in the NRCs knowledge management program. As such, please note that the recorded contents of the session, including any questions posted by the audience members, will be preserved in accordance with the NRCs record management program and, moreover, subject to FOIA disclosure. Please refrain from including any sensitive information (i.e., SUNSI) in any questions that you may ask.

THE PLANT WITHSTOOD THIS CHALLENGE INTACT IN LARGE PART BECAUSE OF COMMENDABLE PERFORMANCE BY NRC INSPECTORS, ANALYSTS, AND MANAGERS THE PREVIOUS YEAR.

-The NRC and Nuclear Power Plant Safety in 2011: Living on Borrowed Time DAVID LOCHBAUM Union of Concerned Scientists Fort Calhoun Station

Licensee: Omaha Public Power District Combustion Engineering 1500 MWt (478 Mwe)

Construction: 1966-1973 Cost: $175 Million (est. 2022, $1.15 Billion)

Operation: 1973-2016

Currently in Decommissioning Fort Calhoun Station

Omaha, NE Design and Licensing Basis for Flood Protection at FCS

• Construction and Design Licensing was completed under the Atomic Energy Commission

- 10 CFR Part 100, Reactor Site Criteria

- 1967 Draft Design Criteria(now App A to 10 CFR Part 50)

• No Regulatory Guides or Standard Review Plan guidance were available to aid licensing reviews.

• AECs design basis decisions were made through letters, telephone, and meetings.

• For Pre-GDC plants, these decisions are usually preserved in the PSAR, FSAR, FSAR Questions, Safety Evaluation Report, and associated references.

Design and Licensing Basis for Flood Protection at FCS

• Design basis flood levels for Fort Calhoun Station were established through correspondence between OPPD and US Army Corps of Engineers, reflected in PSAR, FSAR and SER. These were:

- 1004.2 feet MSL - 1/1000 year flood level (base level of the site)

- 1009.3 feet MSL - Probable Maximum Flood (Rainstorm plus Gavins Point Dam peak discharge)

- 1014 feet MSL - Failure of upstream dams

• These values and protective actions were translated into the Technical Specification and Abnormal Operating Procedures.

1014 Ft MSL Unsealed Penetration

1009.5 Ft MSL

1004 Ft MSL

June 7, 2011, Alert declared for breaker fire loss of spent fuel cooling NRC Emergency

Response

• Fort Calhoun was in an extended outage at the time of event.

• Response Mode: NORMAL

- Augmented Resident Staff for 24-hour coverage

- 2 Residents, 3 additional inspectors, and Branch Chief

- Late May 2011 to Late August 2011

• Suspended the Baseline inspection program

• Postponed supplemental IP 95002 inspection for the Yellow Flood Finding

• Inspectors shifted from identifying performance deficiencies to identifying industrial hazards that could harm flood protection.

Insights for Enhancing Flood Protection and Risk Assessment

1. Rivers Change

2. Experience with Sandbags

3. Maintenance of Structures and Barriers during the Event

4. Potential Hazardous Attitudes and Stress

Video

Hazards

Video

Video

Video Aftermath

Recovery activities began in September 2011. NRC issued a Confirmatory Action Letter to codify flood recovery commitments and restart checklist.

In December 2011, NRC placed Fort Calhoun Station into Manual Chapter 0350 oversight.

Yellow Flood Finding, White Finding for Reactor Trip Contactors, additional Security Greater than Greens, and Breaker Fire in Safety Bus(eventually Red Finding)

In June 2012, an updated Confirmatory Action Letter and Restart Checklist issued. CAL closed in December 2013.

Plant restarted in January 2014. Plant w as shutdown for March 2011 to January 2014.

Plant was permanently shutdown in October 2016.

Contact Info:

Gerond George NRC Region IV Gerond.George@nrc.gov 8172001562