ML083330167

Draft RAI on Proposed Amendment Regarding Degraded Voltage Maximum Allowable Value

ML083330167
Person / Time
Site:	Duane Arnold
Issue date:	11/28/2008
From:	Tam P Plant Licensing Branch III
To:	Browning T, Catron S Duane Arnold
Feintuch K, NRR/DORL/LPL2-1, 415-3079
References
TAC MD8950
Download: ML083330167 (2)

Text

Accession No. ML0833330167 From:

Peter Tam Sent:

Friday, November 28, 2008 10:56 AM To:

Tony; Catron, Steve Cc:

Karl Feintuch; Vijay Goel; Kenneth Miller (NRR)

Subject:

Duane Arnold - Draft RAI re. proposed amendment on degraded voltage allowed value (TAC MD8950)

Tony:

By application dated 5/30/08, as supplemented by letter dated 9/10/08, FPL Energy Duane Arnold proposed to change the maximum allowable value for the 4160-volt emergency bus undervoltage relays. The NRC staff's review of that application is ongoing, and has generated the following two draft questions for your consideration. Please call me to set up a conference call to discuss these draft questions:

1. Provide excerpts from documents which explain that the emergency bus voltage will recover to 95.5% (upper analytical value of degraded voltage relay) following the worst-case design-basis accident. Confirm whether the worst-case scenario is when the maximum safety-related loads are fed from the standby transformer, whose tap setting was changed to get the transformer secondary voltage by approximately 2.8%

(according to the Licensee Event Report No. 2007-10-00 dated January 29, 2008).

2. Provide the minimum switchyard voltage value and its basis assumed in the above requested document.

The sole purpose of this e-mail is to prepare you and others for the proposed conference call. This e-mail does not formally request for additional information, and does not convey a formal NRC staff position.

Peter S. Tam, Senior Project Manager (Project Manager for Duane Arnold, Kewaunee, and Monticello)

Plant Licensing Branch 3-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Tel. 301-415-1451 E-mail Properties Mail Envelope Properties (3D6B1F4F51D25E4E9B6C93FF92DAE5171443BF2E30)

Subject:

Duane Arnold - Draft RAI re. proposed amendment on degraded voltage allowed value (TAC MD8950)

Sent Date: 11/28/2008 10:56:07 AM Received Date: 11/28/2008 10:56:00 AM From: Peter Tam

Created By: Peter.Tam@nrc.gov Recipients:

Browning@fpl.com (Tony)

Tracking Status: None Steve.Catron@fpl.com (Catron, Steve)

Tracking Status: None Karl.Feintuch@nrc.gov (Karl Feintuch)

Tracking Status: None Vijay.Goel@nrc.gov (Vijay Goel)

Tracking Status: None Kenneth.Miller2@nrc.gov (Kenneth Miller (NRR))

Tracking Status: None Post Office:

HQCLSTR02.nrc.gov Files Size Date & Time MESSAGE 8493 11/28/2008 Options Expiration Date:

Priority: olImportanceNormal ReplyRequested: False Return Notification: False Sensitivity: olNormal Recipients received: