Text

Response to Generic Letter 2006-03, Potentially Nonconforming Hemyc and MT Fire Barrier Configurations
	ML061660087
Person / Time
Site:	Fermi
Issue date:	06/09/2006
From:	Cobb D; Detroit Edison
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	+kBR1SISP20060621, GL-06-003, NRC-06-0042
	Download: ML061660087 (6)
	v • d • e

Donald K. Cobb Assistant Vice President, Nuclear Generation Fermi 2 6400 North Dixie lHw., NeNw)ort, MI 48166 Tel: 734.586.5201 Fax: 734.586.4172 DTE Energy-10 CFR 50.54(f)

June 9, 2006 NRC-06-0042 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike Rockville, Maryland 20852

References:

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

2) NRC Generic Letter 92-08, "Thermo-Lag 330-1 Fire Barriers,"

dated December 17, 1992

3) Detroit Edison Letter to NRC, "Detroit Edison Response to NRC Generic Letter 92-08," NRC-93-0043, dated April 8, 1993

4) NRC Letter to Detroit Edison, "Request for Additional Information Regarding Generic Letter 92-08, Thermo-Lag 330-1 Fire Barriers,"

dated December 22, 1993

5) Detroit Edison Letter to NRC, "Detroit Edison Response to NRC Request for Additional Information Regarding Generic Letter 92-08," NRC-94-0011, dated February 11, 1994

6) NRC Letter to Detroit Edison, "Follow-up to the Request for Additional Information Regarding Generic Letter 92-08 Issued Pursuant to 10 CFR 50.54(f) on December 22, 1993 - Fermi 2 (TAC No. M85550)," dated September 19, 1994

7) NRC Letter to Detroit Edison, "Response to Request for Additional Information Regarding Use of Thermo-Lag 330-1 at Fermi 2 (TAC No. M85550)," dated April 18, 1995

USNRC NRC-06-0042 Page 2

8) Detroit Edison Letter to NRC, "Confirmation of Modifications Regarding Removal, Replacement, and Reclassification of Thermo-Lag 330-1 Fire Barriers at Fermi 2," NRC-95-0058 dated June 15, 1995

9) NRC Generic Letter 2006-03, "Potentially Nonconforming HEMYC and MT Fire Barrier Configurations," dated April 10, 2006

Subject:

Detroit Edison Response to Generic Letter 2006-03, Potentially Nonconforming HEMYC and MT Fire Barrier Configurations The purpose of this letter is to provide the information requested in NRC Generic Letter (GL) 2006-03 (Reference 9). On April 10, 2006, the NRC issued GL 2006-03 requesting licensees to determine whether or not Hemyc or MT fire barrier material is installed and relied upon for separation and/or safe shutdown purposes to satisfy applicable regulatory requirements, within 60 days of the date of this letter. In addition, licensees are asked to describe controls that were used to ensure the adequacy of other fire barrier types, consistent with the assessment requested in GL 92-08.

The enclosure to this letter provides Detroit Edison's response to the information requested in GL 2006-03.

No commitments are being made in this letter.

Should you have any questions or require additional information, please contact Mr. Ronald W. Gaston of my staff at (734) 586-5197.

Sincerely, Enclosure cc: D.H. Jaffe C. A. Lipa NRC Resident Office Regional Administrator, Region III Supervisor, Electric Operators, Michigan Public Service Commission

USNRC NRC-06-0042 Page 3 I, DONALD K. COBB, do hereby affirm that the foregoing statements are based on facts and circumstances which are true and accurate to the best of my knowledge and belief.

DONALD K. COBB Assistant Vice President, Nuclear Generation On this _ _ _ day of Iii . 2006 before me personally appeared Donald K. Cobb, being first duly sworn and says that he executed the foregoing as his free act and deed.

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Enclosure to NRC-06-0042 Page 1 RESPONSE TO INFORMATION REQUESTED IN GENERIC LETTER 2006-03, POTENTIALLY NONCONFORMING HEMYC AND MT FIRE BARRIER CONFIGURATIONS

1. Within 60 days of the date of this GL, provide the following:

a. A statement on whether Hemyc or MT fire barrier material is used at their NPPs and whether it is relied upon for separation and/or safe shutdown purposes in accordance with the licensing basis, including whether Hemyc or MT is credited in other analyses (e.g., exemptions, license amendments, GL 86-10 analyses).

Response

Detroit Edison does not use or install Hemyc or MT fire barrier material.

b. A description of the controls that were used to ensure that other fire barrier types relied on for separation of redundant trains located in a single fire area are capable of providing the necessary level of protection. Addressees may reference their responses to GL 92-08 to the extent that the responses address this specific issue.

Response

Detroit Edison has installed one hour rated fire barrier wrap using 3M product E-54A material for cable tray fire wrap systems as referred to in References 3, 5, and 8 in responses to GL 92-08. These fire barriers were installed on cable trays and cable tray supports in the Auxiliary Building basement and fifth floor.

The length of wrap on the Auxiliary Building basement is approximately eighty feet per tray on four trays stacked vertically, and the length of wrap on the Auxiliary Building fifth floor cable tray enclosure is approximately twenty-six feet. The cable trays within the wrap are six inches by twenty-four inches in width, and six inches by twelve inches in width ladder trays.

The cable trays carry power and control circuits, and the fire barrier wrap is installed to maintain one division free of fire damage.

In addition, Detroit Edison will be installing additional one hour rated fire barrier wrap using 3M product E-54A material on cable trays and cable tray supports, and a conduit in the Auxiliary Building first floor Mezzanine and Cable Tray Area. These installations are scheduled to be completed in December 2006.

The length of wrap on the Auxiliary Building first floor is approximately fifty feet on horizontal tray IK-029, thirty feet on vertical trays 1K-0 14 and 1K-034, including the cable tray supports, and approximately twenty feet on

Enclosure to NRC-06-0042 Page 2 conduit JA-001-1K. The cable trays within the wrap are six inches by twenty-four inches in width solid bottom trays, and the conduit is a two inch rigid steel conduit. The cable trays and conduit carry control and instrumentation circuits, and the fire barrier wrap is installed to maintain one division free of fire damage.

3M products M-20 and CS-195 were installed as cable tray and support barriers in the 1980s during construction. These materials were installed in various areas in the auxiliary building to maintain one division free of fire damage.

The controls used to insure that these fire wraps provide the necessary level of protection included purchasing and installing the materials using documented vendor installation instructions based on qualified test reports.

Quality Control measures were implemented by having vendor quality control and technical representatives onsite during the installation to witness and verify that the installation met their quality control and technical requirements, and to have Detroit Edison quality control representatives provide oversight of the project to verify that the installation was in accordance with Detroit Edison requirements.

The Auxiliary Building basement has automatic detection and suppression.

The Auxiliary Building fifth floor has automatic detection, and an approved deviation for lack of automatic suppression. The Auxiliary Building first floor has automatic detection and suppression, and a deviation for intervening combustibles in the cable trays that interact between the two shutdown divisions. This deviation was granted based on the fire breaks installed in the trays, covered instrument trays, and full area suppression.

The 3M product E-54A fire barrier material qualification tests were performed using the requirements of GL 86-10 Supplement 1.

2. Within 60 days of the date of this GL, for those addressees that have installed Hemyc or MT fire barrier materials, discuss the following in detail:

a. The extent of the installation (e.g., linear feet of wrap, areas installed, systems protected),

b. Whether the Hemyc and/or MT installed in their plants is conforming with their licensing basis in light of recent findings, and if these recent finding do

.not apply, why not,

Enclosure to NRC-06-0042 Page 3

c. The compensatory measures that have been implemented to provide protection and maintain the safe shutdown function of affected areas of the plant in light of the recent findings associated with Hemyc and MT installations, including evaluations to support the addressees' conclusions, and

d. A description of, and implementation schedules for, corrective actions, including a description of any licensing actions or exemption requests needed to support changes to the plant licensing basis.

Response

Since Detroit Edison does not use or install Hemyc or MT fire barrier materials, this question does not apply.

3. No later than December 1, 2007, addressees that identified in L.a. Hemyc and/or MT configurations are requested to provide a description of actions taken to resolve the nonconforming conditions described in 2.d.