NRC-12-0049, Response to Request for Additional Information Regarding Revised Relief Request No. PRR-002 for the Inservice Testing Program Third 10-Year Interval

Response to Request for Additional Information Regarding Revised Relief Request No. PRR-002 for the Inservice Testing Program Third 10-Year Interval

ML12205A067
Person / Time
Site:	Fermi
Issue date:	07/20/2012
From:	Plona J Detroit Edison, DTE Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NRC-12-0049, PRR-002
Download: ML12205A067 (4)

Text

Joseph H. Plona Site Vice President 6400 N. Dixie Highway, Newport, MI 48166 Tel: 734.586.5910 Fax: 734.586.4172 DTE Energy-10 CFR 50.55a July 20, 2012 NRC-12-0049 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington D C 20555-0001

References:

1) Fermi 2 NRC Docket No. 50-341 NRC License No. NPF-43

2) Detroit Edison's Letter to NRC, "Submittal of Revised Relief Request No. PRR-002 for the Inservice Testing Program Third 10-Year Interval," NRC-12-0015, dated February 20, 2012

[ADAMS Accession No. ML12052A043]

Subject:

Response to Request for Additional Information Regarding Revised Relief Request No. PRR-002 for the Inservice Testing Program Third 10-Year Interval In Reference 2, Detroit Edison requested NRC approval of end date extension for Inservice Testing Program Relief Request PRR-002 for the third 10-year interval at Fermi 2. Relief from individual Core Spray pump testing and the performance of the first Comprehensive Pump Test (CPT) was requested to be extended from February 17, 2013 until the startup from the 17t" refueling outage (RF17) in 2015. In addition, relief from the use of a single flow reference value was requested to be extended from February 17, 2014 until one year after startup from RF17 to allow for one additional year to assess system flow throttling capability following completion of the plant modification. Based on the current 18-month operating cycles, two additional refueling outages are required to complete the implementation of plant modification to permit single pump testing.

In an e-mail from Mr. Mahesh Chawla to Mr. Alan Hassoun dated June 11, 2012, the NRC requested additional information regarding the Relief Request extension. The enclosure to this letter provides Detroit Edison's response to the requested information.

USNRC NRC-12-0049 Page 2 No new commitments are being made in this submittal.

Should you have any questions or require additional information, please contact Mr. Rodney W. Johnson of my staff at (734) 586-5076.

Sincerely,

Enclosure:

Response to Request for Additional Information cc: NRC Project Manager NRC Resident Office Reactor Projects Chief, Branch 4, Region III Regional Administrator, Region III Supervisor, Electric Operators, Michigan Public Service Commission

Enclosure to NRC-12-0049 Fermi 2 NRC Docket No. 50-341 Operating License No. NPF-43 Response to Request for Additional Information

Enclosure to NRC-12-0049 Page 1 Detroit Edison's Response to NRC Request for Additional Information (RAI):

NRC RAI:

Please provide more detail on why the design and procurement activities for this modification necessitate slipping the original modification date for two additional refueling outages.

Response

Current work control procedures at Fermi 2 include core milestone requirements for completing refueling outage modification design and work packages. The milestone for issuing engineering packages is one year prior to the start of the outage and the milestone for completing work packages is nine months before the start of the outage. These milestones are designed to ensure adequate time is provided to develop and review a quality design product, avoid schedule pressure and minimize risk and other challenges to station processes and personnel.

In February 2012, a detailed scope document for the Core Spray test line modification, consistent with the revised scope described in Reference 2, was developed and approved by senior management. The scope involves the use of "drag" valves with multi-stage pressure reducing elements to replace the current test throttle valves. The purchase documentation and lead time required to procure these customized valves is approximately 50 weeks. This process involves several key steps including the Preparation of the Purchase Specification, internal corporate and legal review of the document, issuance of the purchase order and vendor acceptance, and vendor manufacturing and delivery of the valves and associated documentation.

Upon receipt of the valves with the detailed design documentation from the vendor including weight, dimensions and center of gravity, the dynamic analysis for the suppression pool attached piping can be formalized into a design calculation. It is estimated that the analysis and review would take approximately four months to complete. In parallel with this effort, the preparation, review and approval of the final engineering package will be performed and would typically require between three and four months to complete.

Detroit Edison carefully considered expediting the activities required to complete the installation of the Core Spray modification to attain single pump test capability with the upcoming 16" refueling outage (RF16), currently scheduled in the fall of 2013. However, based on the long lead time for procuring the valves and the complex dynamic analysis of the suppression pool attached piping, it was determined that a more orderly schedule that meets the work control milestone procedural requirements would be pursued. This modification is currently scheduled to be implemented in RF17.