L-PI-14-023, Request for NRC Assistance to Obtain Information on Dams from the U.S. Army Corps of Engineers

Request for NRC Assistance to Obtain Information on Dams from the U.S. Army Corps of Engineers

ML14064A291
Person / Time
Site:	Prairie Island
Issue date:	03/05/2014
From:	Davison K Northern States Power Co, Xcel Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-PI-14-023
Download: ML14064A291 (5)

Text

Prairie Island Nuclear Generating Plant 1717 Wakonade Drive East Welch, MN 55089 L-P 1-14-023 MAR 0 5 2014 10 CFR 50.4 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Prairie Island Nuclear Generating Plant Units 1 and 2 Docket Nos. 50-282 and 50-306 Renewed License Nos. DPR-42 and DPR-60 Request for NRC Assistance to Obtain Information on Dams from the U.S. Army Corps of Engineers (USAGE)

References:

1. NRC Letter, "Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident," dated March 12, 2012 (ADAMS Accession No. ML12053A340).

2. NRC Interim Staff Guidance JLD-ISG-2013-01, "Guidance for Assessment of Flooding Hazards Due to Dam Failure," Revision 0, July 29, 2013 (ADAMS Accession No. ML13151A153).

On March 12, 2012, the Nuclear Regulatory Commission (NRC) Staff issued Reference 1 to all NRC power reactor licensees and holders of construction permits in active or deferred status. Enclosure 2 of Reference 1 contains specific Requested Actions, Requested Information, and Required Responses associated with Near-Term

- Task Force (NTTF) Recommendation 2.1 for flooding hazards. The NRC staff issued Reference 2 to provide guidance acceptable to the NRC staff for re-evaluating flooding hazards due to dam failure. The NRC staff position in Reference 2, Section 1.5.3, states, in part, "If a Federally owned dam is identified as critical to the flooding reanalysis, the licensee should contact the NRC promptly. The NRC will act as the interface between these agencies and licensees."

Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy, requests the assistance of the NRC to obtain information needed to complete the flooding hazard re-evaluation for Prairie Island Nuclear Generating Plant (PINGP), Units 1 and 2, which is required by the 10 CFR 50.54(f) letter. Specifically, NSPM requests

Document Control Desk Page 2 that the NRC act as the interface between NSPM as outlined in Section 1.5.3 of Reference 2.

The specific information needed to support the flood hazard reevaluation for PINGP is identified in the enclosure to this letter.

If there are any questions or if additional information is needed, please contact Jennie Wike, Licensing Engineer, at 612-330-5788.

Summary of Commitments This letter makes no new commitments and no revisions to existing commitments.

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Kevin Davison Site Vice President, Prairie Island Nuclear Generating Plant Northern States Power Company - Minnesota cc: Administrator, Region Ill, USNRC Director of Nuclear Reactor Regulation (NRR), USNRC NRR Project Manager, Prairie Island Nuclear Generating Plant, USNRC Senior Resident Inspector, Prairie Island Nuclear Generating Plant, USNRC

PRAIRIE ISLAND NUCLEAR GENERATING PLANT, UNITS 1 AND 2 Request for NRC Assistance to Obtain Information on Dams from the U.S. Army Corps of Engineers (USACE)

Requested Information from the USAGE Page 1 of 3

Enclosure NSPM Requested Information from the USACE To appropriately respond to the Nuclear Regulatory Commission (NRC) letter dated March 12, 2012 (Reference 1), Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy, requests information be provided from the U.S.

Army Corps of Engineers (USACE) to the NRC for the following dams:

• Marsh Lake Dam

• Lac Qui Parle Dam

• Highway 75 Dam

• Browns Valley Dike

• Pine River Dam

• Sandy Lake Dam and Lock

• Pokegama Lake Dam

• Leech Lake Dam

• Gull Lake Dam

• Saint Anthony Falls Upper Lock and Dam

• Saint Anthony Falls Lower Lock and Dam

• Lock and Dam #1

• Lock and Dam #2

• Lock and Dam #3

• Lake Winnibigoshish NSPM requests study information and results for the dams that USACE has either already completed or may complete in response to this data request. NSPM requests summaries of all completed and pending dam failure analyses performed using the methods and assumptions compliant with JLD-ISG-2013-01 (Reference 2), including the following information:

• Breach development assumptions (type, shape and timing of breach)

• Breach triggering assumptions (i.e. water surface elevation, duration of overtopping, flow velocity, etc.) for target dam and cascading failures of downstream dams

• Concurrent flow conditions (inflow hydrographs and base flows)

• Operations assumptions

• Flow and elevation hydrographs for breach and no-breach scenarios at key locations, including at the target dam, at any downstream dams, and at locations near the Prairie Island Nuclear Generating Plant site as designated by NSPM Additionally, NSPM requests information and data for dams that USACE has not yet evaluated for breach using the methods and assumptions compliant with Reference 2 and that USACE does not intend to evaluate during the course of the data request.

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Enclosure NSPM Requested Information from the USACE These data request items may be used by NSPM for an in-house dam breach analysis.

This information request includes:

• Any changes to assumptions and data incorporated in prior breach studies

• Dam and gate geometry, including dimensions and elevations

• Stage- storage curves

• Current operations and operational assumptions under normal and flood conditions

• Project discharge rating curves that cover normal condition and flood operations

• Inflow hydrographs used in the breach analysis

• Potential breach locations (spillway, embankment, dike, etc.) and associated trigger events (water surface elevation, overtopping duration, flow velocity, etc.)

• Potential for debris impacts on gate operations

References:

1. NRC Letter, "Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident,"

dated March 12, 2012 (ADAMS Accession No. ML12053A340).

2. NRC Interim Staff Guidance JLD-ISG-2013-01, "Guidance for Assessment of Flooding Hazards Due to Dam Failure," Revision 0, July 29, 2013 (ADAMS Accession No. ML13151A153).

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