ML13241A216

Request to Obtain U.S. Army Corps of Engineers Information to Support Development of Flood Hazard Reevaluation Response

ML13241A216
Person / Time
Site:	Fort Calhoun
Issue date:	09/17/2013
From:	Joseph Sebrosky Plant Licensing Branch IV
To:	Cortopassi L Omaha Public Power District
Sebrosky J
References
Download: ML13241A216 (3)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 September 17, 2013 Mr. Louis P. Cortopassi Site Vice President and Chief Nuclear Officer Omaha Public Power District Fort Calhoun Station 9610 Power Lane, Mail Stop FC-2-4 Omaha, NE 68008

SUBJECT:

FORT CALHOUN STATION, UNIT NO.1 - REQUEST TO OBTAIN U.S. ARMY CORPS OF ENGINEERS INFORMATION TO SUPPORT DEVELOPMENT OF FLOOD HAZARD REEVALUATION RESPONSE

Dear Mr. Cortopassi:

By letter dated August 26, 2013 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13240A128), Omaha Public Power District (OPPD) requested Nuclear Regulatory Commission (NRC) staff assistance in obtaining information from the U.S.

Army Corps of Engineers (USACE) to support OPPD's development of a flood hazard reevaluation (FHR) response to the March 12,2012, request for information (ADAMS Accession No. ML12073A348). In your letter dated August 26,2013, you provide a list of information needs in order to complete the FHR for Fort Calhoun Station, Unit No.1, (FCS) in accordance with interim staff guidance JLD-ISG-2013-01, "Guidance For Assessment of Flooding Hazards Due to Dam Failure," Revision 0, dated July 29, 2013 (ADAMS Accession No. ML13151A153).

You note in your letter that in accordance with JLD-ISG-2013-01, because the main stem dams along the Missouri River are owned by a federal entity (Le., USACE) and are critical to the FHR, the NRC staff will act as the interface between the USACE and OPPD.

The NRC staff is in the process of developing a contract to have USACE perform the portion of the FCS FHR associated with the assessment of flood hazards due to flooding in streams and rivers, including potential site flooding due to dam failures. USACE is expected to perform these analyses in accordance with the March 12, 2012, request for information and the guidance outlined in JLD-ISG-2013-01. The NRC staff expects OPPD to respond to all other portions of the FHR in accordance with the process outlined in Enclosure 2 of the March 12, 2012, request for information. Enclosure 2 of the March 12, 2012, request for information provides details for what the FHR report should include. The NRC staff expects the following:

• Item 1.a - OPPD will provide site information related to the flood hazard.

• Item 1.b - OPPD will provide an evaluation of all flood-causing mechanisms, based on present-day methodologies and regulatory guidance except for the evaluation of potential site flooding due to upstream dam failure. As discussed above, the USACE is expected to perform the portion of the evaluation associated with the potential for site flooding due to failure of upstream dams. The NRC staff expects OPPD will address all

L Cortopassi -2 other hazard mechanisms as part of Item 1.b including an analysis of local intense precipitation and site drainage.

• Item 1.c - OPPD will provide a comparison of current and reevaluated flood causing mechanisms at the site.

• Item 1.d - OPPD will provide, if necessary, an interim evaluation and actions taken or planned to address any higher flooding hazards relative to the design basis, prior to completion of the integrated assessment described in the March 12, 2012, request for information.

• Item 1.e - OPPD will provide additional actions beyond those identified in Item 1.d taken or planned to address flood hazards, if any.

When the results of the USACE portion of the FHR associated with flooding in streams and rivers from potential dam failures are available they will be provided to you for your review and action, as necessary. The staff is considering the appropriate level of engagement with the USACE as they develop their portion of the FHR to ensure that the analysis is performed in accordance with present-day NRC methodologies and regulatory guidance. The NRC staff will keep you informed of USACE's progress in developing their portion of the FCS FHR. At some future time the NRC staff may request OPPD involvement when the USACE portion of the FHR models and results are discussed between the NRC staff and the USACE staff.

If you have any questions, please contact me at 301-415-1132 or via e-mail at joseph. sebrosky@nrc.gov Sincerely Docket No. 50-285 cc: Distribution via Listserv

ML13241A216

! OFFICE NRRJDORLlLPL4/PM NRRJDORLlLPL4/LA NRRJJLD/BC Ii NAME JSebrosky JBurkhardt GWilson DATE 9/13/13 8/29/13 9/10/13 OFFICE NRO/DSEAlRHEB/BC OGC NRRJDORLlLPL4/BC I NAME CCook BHarris (NLO) MMarkley

• DATE 9/11/13 9/12/13 9/17113

• OFFICE NRRJDORLlLPL4/PM IlNAME JSebrosky I IDATE 9/17/13

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