05000341/LER-2016-003, Cancellation of Licensee Event Reports (Lers) for Secondary Containment Wind Events: LER-16-003, LER 16-004, LER 16-007, Er 16-008, LER 16-010, LER 16-013; LER 16-014, LER 15-015, LER 16-016 and LER 16-017

Cancellation of Licensee Event Reports (Lers) for Secondary Containment Wind Events: LER-16-003, LER 16-004, LER 16-007, Er 16-008, LER 16-010, LER 16-013; LER 16-014, LER 15-015, LER 16-016 and LER 16-017

ML17079A003
Person / Time
Site:	Fermi
Issue date:	03/17/2017
From:	Polson K DTE Electric Company
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 16-003, LER 16-004, LER 16-007, LER 16-008, LER 16-010, LER 16-013, LER 16-014, LER 16-015, LER 16-016, LER 16-017, NRC-17-0029
Download: ML17079A003 (6)

LER-2016-003, Cancellation of Licensee Event Reports (Lers) for Secondary Containment Wind Events: LER-16-003, LER 16-004, LER 16-007, Er 16-008, LER 16-010, LER 16-013; LER 16-014, LER 15-015, LER 16-016 and LER 16-017

Event date:
Report date:
3412016003R00 - NRC Website

text

Keith J. Poison Site Vice President DTE Energy Company 6400 N. Dixie Highway, Newport, MI 48166 Tel: 734.586.4849 Fax: 734.586.4172 Email: keith.polsonadteenergy.com r

DTE Energy 1 OCFR50.72 10CFR50.73 March 17, 2017 NRC-17-0029 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001

Reference:

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

Subject:

Cancellation of Licensee Event Reports (LERs) for Secondary Containment Wind Events:

Licensee Event Report No. 2016-003 Licensee Event Report No. 2016-004 Licensee Event Report No. 2016-007 Licensee Event Report No. 2016-008 Licensee Event Report No. 2016-010 Licensee Event Report No. 2016-013 Licensee Event Report No. 2016-014 Licensee Event Report No. 2016-015 Licensee Event Report No. 2016-016 Licensee Event Report No. 2016-017 In the subject Licensee Event Reports (LERs), DTE Electric Company (DTE) reported conditions whereby the Fermi 2 secondary containment was believed to have exceeded Technical Specification Surveillance Requirements due to high winds. DTE wishes to cancel the subject LERs, as the Fermi 2 secondary containment has been determined to have been Operable during each of these events as described below.

USNRC NRC-17-0029 Page 2 The Fermi 2 secondary containment pressure is maintained at a pressure less than the external pressure to contain, dilute, hold up and reduce the activity level of fission products prior to release to the environment and to isolate and contain fission products that are released during a Design Basis Accident or certain operations. Secondary containment pressure is monitored by a number of differential pressure (dP) sensors.

High wind gusts have resulted in momentary negative pressure on the leeward side of the building causing a more positive pressure indication from one or more dP sensors.

The secondary containment building pressure remains relatively constant during these "wind events."

In December 2016, DTE implemented a software design change to display a 120-second rolling average for secondary containment dP indication. A 120-second rolling average recorded every second provides the operator a more accurate report of actual secondary containment conditions, while mitigating the signal noise and wind gust effects. The conditions associated with the subject LERs were re-reviewed in light of the improved secondary containment dP indication and it was determined that the Fermi 2 secondary containment was Operable during each of the events delineated in the subject LERs. Specifically, the secondary containment pressure did not exceed Technical Specification Surveillance Requirements during these events. The Event Notifications in Enclosure 1 will be retracted using Enclosure 1 as the template. Event Notifications are the Event Notifications associated with the LERs being retracted by this letter.

In summary, the subject Licensee Event Reports should be canceled because the Fermi 2 secondary containment was determined to have been fully Operable during the conditions identified in the subject reports. LER numbers 2016-003, 2016-004, 2016-007, 2016-008, 2016-010, 2016-013, 2016-014, 2016-015, 2016-016, and 2016-017 for docket 00500341 will not be used.

Should you have any questions or require additional information, please contact Mr.

Scott A. Maglio, Manager - Nuclear Licensing at (734) 586-5076.

Sincerely, Keith J. Polson Site Vice President Enclosure: Event Notification Retraction

USNRC NRC-17-0029 Page 3 cc: (with Enclosure)

NRC Project Manager NRC Resident Office Reactor projects Chief, Branch 5, Region III Regional Administrator, Region III Michigan Public Service Commission Regulated Energy Division (kindschl@michigan.gov)

Enclosure to NRC-17-0029 Event Notification Retraction

Enclosure to NRC-17-0029 Page 1 Event Notifications Retraction Notification Time Facility Fermi Unit 2 Name of Caller Call Back #

Event Time & Zone Event Date Power/Mode Before 100%/Power Operation Power/Mode After 100%/Power Operation

Description

The following event notifications are retracted:

Event Number Event Date 52076 07/08/2016 52084 07/13/2016 52205 08/27/2016 52320 10/26/2016 52380 11/20/2016 52398 11/29/2016 52432 12/14/2016 52434 12/14/2016 52437 12/15/2016 In these event notifications DTE Electric Company (DTE) reported conditions whereby the Fermi 2 secondary containment was believed to have exceeded Technical Specification Surveillance Requirements due to high winds. DTE hereby retracts the above Event Notifications as the Fermi 2 secondary containment has been determined to have been Operable during each of these events as described below.

The Fermi 2 secondary containment pressure is maintained at a pressure less than the external pressure to contain, dilute, hold up and reduce the activity level of fission products prior to release to the environment and to isolate and contain fission products that are released during a Design Basis Accident or certain operations. Secondary containment pressure is monitored by a number of differential pressure (dP) sensors. High wind gusts have resulted in momentary negative pressure on the leeward side of the building causing a more positive pressure indication from one or more dP sensors. The secondary containment building pressure remains relatively constant during these "wind events."

In December 2016, DTE implemented a software design change to display a 120-second rolling average for secondary containment dP indication. A 120-second rolling average recorded every second provides the operator a more accurate report of actual secondary containment conditions, while mitigating the signal noise and wind gust effects. The conditions associated with the

Enclosure to NRC-17-0029 Page 2 subject Event Notifications were re-reviewed in light of the improved secondary containment dP indication and it was determined that the Fermi 2 secondary containment was Operable during each of the events delineated in the above Event Notifications. Specifically, the secondary containment pressure did not exceed Technical Specification Surveillance Requirements during these events.

In summary, the above Event Notifications are retracted because the Fermi 2 secondary containment was determined to have been fully Operable during the conditions identified in the subject reports.