NG-12-0152, Withdrawal of LER 50-331/2012-001

Withdrawal of LER 50-331/2012-001

ML12090A611
Person / Time
Site:	Duane Arnold
Issue date:	03/30/2012
From:	Wells P NextEra Energy Duane Arnold
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 12-001-00, NG-12-0152
Download: ML12090A611 (1)

Text

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ARNOLD March 30, 2012 NG-12-0152 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555-0001 Duane Arnold Energy Center Docket 50-331 Renewed Op. License No. DPR-49 Withdrawal of LER 50-331/2012-001

Reference:

Letter from P. Wells (NextEra Energy Duane Arnold) to USNRC, "License Event Report #2012-001-00," NG-12-0045, dated January 31,2012, ML12032A041.

On January 31,2012, NextEra Energy Duane Arnold submitted Licensee Event Report (LER) 50-331/2012-001 pursuant to 10 CFR 50.73(a)(2)(v)(B)/(D) and 50.73(a)(2)(vii). This LER reported an unplanned inoperability of the Low Pressure Coolant Injection (LPCI) system due to the presence of discharge line gas voiding. As stated in the LER, the void was estimated to be between 1.5 to 2.0 cubic feet.

The Residual Heat Removal (RHR) system at Duane Arnold is part of the safety injection system. LPCI is one of the functions of the RHR system. In order to determine the potential effect of the gas void on the RHR system, a detailed hydraulic and structural analysis of all affected portions of the system was completed to evaluate the past operability of the RHR LPCI function. Based on this analysis, NextEra Energy has concluded the RHR piping and supports have sufficient capacities to meet operability acceptance criteria when evaluated for the gas void compression hydraulic event combined with applicable design basis events.

Therefore, LPCI initiation in response to a Loss of Coolant Accident (LOCA) with a 2.0 cubic foot gas void would not have challenged the structural integrity of the piping and consequently the operability of the RHR system. The RHR system would have performed its design safety function of LPCI in the event of a LOCA.

Based on the above, the issue in question is not reportable, and therefore NextEra Energy herby withdrawals LER 50-331/2012-001-00. If you have any questions, please call Steve Catron, Licensing Manager at (319) 851-7234.

Peter Wells Vice President, Duane Arnold Energy Center NextEra Energy Duane Arnold, LLC NextEra Energy Duane Arnold, LLC, 3277 DAEC Road, Palo, IA 52324