ULNRC-05415, Day Response to NRC Generic Letter 2007-01, Inaccessible or Underground Power Cable Failures That Disable Accident Mitigation Systems or Cause Plant Transients.

Day Response to NRC Generic Letter 2007-01, Inaccessible or Underground Power Cable Failures That Disable Accident Mitigation Systems or Cause Plant Transients.

ML071350411
Person / Time
Site:	Callaway
Issue date:	05/07/2007
From:	Fitzgerald D AmerenUE, Union Electric Co
To:	Document Control Desk, NRC/NRR/ADRO
References
GL-07-001, ULNRC-05415
Download: ML071350411 (6)

Text

AmerenUE PO Box 620 Cal/awayPlant Fulton, MO 65251 May 7, 2007 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike, Rockville, MD 20852 Ladies and Gentlemen: ULNRC-05415 DOCKET NO. 50-483 CALLAWAY PLANT UNIT 1 wAmeren UNION ELECTRIC CO.

90 DAY RESPONSE TO NRC GENERIC LETTER 2007-01, UE INACCESSIBLE OR UNDERGROUND POWER CABLE FAILURES THAT DISABLE ACCIDENT MITIGATION SYSTEMS OR CAUSE PLANT TRANSIENTS Pursuant to 10 CFR 50.54(f), this letter provides the Union Electric Company (AmerenUE) 90-day response to NRC Generic Letter 2007-01, "Inaccessible or Underground Power Cable Failures that Disable Accident Mitigation Systems or Cause Plant Transients." The generic letter requests licensees to provide a history of inaccessible or underground power cable failures and to describe inspection, testing and monitoring programs to detect the degradation of inaccessible or underground power cables for cables within the scope of 10 CFR 50.65.

There are no commitments made to the NRC by this letter. If you have questions regarding this response, please contact D. E. Shafer at 314-554-3104.

I declare under penalty of perjury that the foregoing is true and correct.

Very truly yours, Executed on the 7 th day of May, 2007.

David T. Fitzgerald Manager - Regulatory Affairs DS/jdg

Attachment:

90-day Response to Generic Letter 2007-01 a subsidiary of Ameren Corporation

ý2I7

4ý ULNRC-05415 May 7, 2007 Page 2 Mr. Bruce S. Mallett Regional Administrator U.S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-4005 Senior Resident Inspector Callaway Resident Office U.S. Nuclear Regulatory Commission 8201 NRC Road Steedman, MO 65077 Mr. Jack N. Donohew (2 copies)

Licensing Project Manager, Callaway Plant Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Mail Stop O-7D1 Washington, DC 20555-2738 Missouri Public Service Commission Governor Office Building 200 Madison Street PO Box 360 Jefferson City, MO 65102-0360 Mr. Ron Reynolds Director Missouri State Emergency Management Agency P.O. Box 116 Jefferson City, MO 65102

ULNRC-05415 May 7, 2007 Page 3 bcc: C. D. Naslund A. C. Heflin D. T. Fitzgerald G. A. Hughes D. E. Shafer S. L. Gallagher (100)

L. M. Belsky (NSRB)

K. A. Mills P. M. Bell A160.0761 Certrec Corporation 4200 South Hulen, Suite 422 Fort Worth, TX 76109 (Certrecreceives ALL attachments as long as they are non-safeguards andpublic disclosed).

Send the following without attachments:

Ms. Diane M. Hooper Mr. Dennis Buschbaum Supervisor, Licensing TXU Power WCNOC Comanche Peak SES P.O. Box 411 P.O. Box 1002 Burlington, KS 66839 Glen Rose, TX 76043 Mr. Scott Bauer Mr. Stan Ketelsen Regulatory Affairs Manager, Regulatory Services Palo Verde NGS Pacific Gas & Electric P.O. Box 52034, Mail Stop 104/5/536 Mail Station 7636 P.O. Box 56 Phoenix, AZ 85072-2034 Avila Beach, CA 93424 Mr. Scott Head Mr. John O'Neill Supervisor, Licensing Pillsbury Winthrop Shaw Pittman LLP South Texas Project NOC 2300 N. Street N.W.

Mail Code N5014 Washington, DC 20037 P.O. Box 289 Wadsworth, TX 77483

Attachment to ULNRC-05415 Page 1 of 3 Response to Requested Information of NRC Generic Letter 2007-01, Inaccessible or Underground Power Cable Failures that Disable Accident Mitigation Systems or Cause Plant Transients Below is the Union Electric Company (AmerenUE) response to the Requested Information of NRC Generic Letter 2007-01, "Inaccessible or Underground Power Cable Failures that Disable Accident Mitigation Systems or Cause Plant Transients." The generic letter's "Requested Information" is shown in bold followed by AmerenUE's response.

NRC Requested Information Item (1):

Provide a history of inaccessible or underground power cable failures for all cables that are within the scope of 10 CFR 50.65 (the Maintenance Rule) and for all voltage levels. Indicate the type, manufacturer, date of failure, type of service, voltage class, years of service, and the root causes for the failure.

AmerenUE Response (1):

Research into inaccessible or underground power cable failures at Callaway Plant revealed one failure in power cables within the scope of 10 CFR 50.65 in the voltage range between 480 VAC and 15,000 VAC. Table 1 contains the information requested as well as additional information on failure type, component supported and cable identifier.

Attachment to ULNRC-05415 Page 2 of 3 NRC Requested Information Item (2):

Describe inspection, testing and monitoring programs to detect the degradation of inaccessible or underground power cables that support EDGs, offsite power, ESW, service water, component cooling water and other systems that are within the scope of 10 CFR 50.65 (the Maintenance Rule).

AmerenUE Response (2):

AmerenUE performs a limited amount of insulation resistance and polarization index testing on selected cables during routine motor circuit evaluation testing, overhaul or maintenance of the equipment they feed. AmerenUE has not implemented other inspection, testing or monitoring programs to detect the degradation of inaccessible or underground power cables.

AmerenUE performs the following actions on a routine basis to eliminate or minimize conditions known to impact cable degradation rates for cables that are within the scope of 10 CFR 50.65:

11 Periodically perform visual inspection for corrosion and degradation of cable tray supports for selected cables.

0 Periodically inspect and dewater selected manholes.

Attachment to ULNRC-05415 Page 3 of 3 Table 1. AmerenUE Inaccessible or Underground Power Cable Failures Failure Type Cable Type Cable Type Type of Service Voltage Class Root Causes for (inservice/ (Insulation (Shielded, Cable Date of (energized/ Component Voltage Class (nominal (cable rating Years of Service the Failure Failure # testing) Type) Yes/No) Manufacturer Failure deenergized) Supported Cable Identifier service voltage) voltage) Prior to Failure (apparent cause)

I Inservice Ethylene No Anaconda Exact date Energized during low UHS sump 6EFGI3PA 480V 600V Approx 6 years Unknown. Details are propylene (Durasheath EP) unknown, temperature heater SEF02D limited for this non-insulation with Identified on operations only safety job. Failed cable Hypalon jacket 1/7/1990 suspected of being subjected to excessive strain during initial installation which led tc eventual failure.

Identical replacement cables in service for 17 years. Cause is unverified.

Text

AmerenUE PO Box 620 Cal/awayPlant Fulton, MO 65251 May 7, 2007 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike, Rockville, MD 20852 Ladies and Gentlemen: ULNRC-05415 DOCKET NO. 50-483 CALLAWAY PLANT UNIT 1 wAmeren UNION ELECTRIC CO.

90 DAY RESPONSE TO NRC GENERIC LETTER 2007-01, UE INACCESSIBLE OR UNDERGROUND POWER CABLE FAILURES THAT DISABLE ACCIDENT MITIGATION SYSTEMS OR CAUSE PLANT TRANSIENTS Pursuant to 10 CFR 50.54(f), this letter provides the Union Electric Company (AmerenUE) 90-day response to NRC Generic Letter 2007-01, "Inaccessible or Underground Power Cable Failures that Disable Accident Mitigation Systems or Cause Plant Transients." The generic letter requests licensees to provide a history of inaccessible or underground power cable failures and to describe inspection, testing and monitoring programs to detect the degradation of inaccessible or underground power cables for cables within the scope of 10 CFR 50.65.

There are no commitments made to the NRC by this letter. If you have questions regarding this response, please contact D. E. Shafer at 314-554-3104.

I declare under penalty of perjury that the foregoing is true and correct.

Very truly yours, Executed on the 7 th day of May, 2007.

David T. Fitzgerald Manager - Regulatory Affairs DS/jdg

Attachment:

90-day Response to Generic Letter 2007-01 a subsidiary of Ameren Corporation

ý2I7

4ý ULNRC-05415 May 7, 2007 Page 2 Mr. Bruce S. Mallett Regional Administrator U.S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-4005 Senior Resident Inspector Callaway Resident Office U.S. Nuclear Regulatory Commission 8201 NRC Road Steedman, MO 65077 Mr. Jack N. Donohew (2 copies)

Licensing Project Manager, Callaway Plant Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Mail Stop O-7D1 Washington, DC 20555-2738 Missouri Public Service Commission Governor Office Building 200 Madison Street PO Box 360 Jefferson City, MO 65102-0360 Mr. Ron Reynolds Director Missouri State Emergency Management Agency P.O. Box 116 Jefferson City, MO 65102

ULNRC-05415 May 7, 2007 Page 3 bcc: C. D. Naslund A. C. Heflin D. T. Fitzgerald G. A. Hughes D. E. Shafer S. L. Gallagher (100)

L. M. Belsky (NSRB)

K. A. Mills P. M. Bell A160.0761 Certrec Corporation 4200 South Hulen, Suite 422 Fort Worth, TX 76109 (Certrecreceives ALL attachments as long as they are non-safeguards andpublic disclosed).

Send the following without attachments:

Ms. Diane M. Hooper Mr. Dennis Buschbaum Supervisor, Licensing TXU Power WCNOC Comanche Peak SES P.O. Box 411 P.O. Box 1002 Burlington, KS 66839 Glen Rose, TX 76043 Mr. Scott Bauer Mr. Stan Ketelsen Regulatory Affairs Manager, Regulatory Services Palo Verde NGS Pacific Gas & Electric P.O. Box 52034, Mail Stop 104/5/536 Mail Station 7636 P.O. Box 56 Phoenix, AZ 85072-2034 Avila Beach, CA 93424 Mr. Scott Head Mr. John O'Neill Supervisor, Licensing Pillsbury Winthrop Shaw Pittman LLP South Texas Project NOC 2300 N. Street N.W.

Mail Code N5014 Washington, DC 20037 P.O. Box 289 Wadsworth, TX 77483

Attachment to ULNRC-05415 Page 1 of 3 Response to Requested Information of NRC Generic Letter 2007-01, Inaccessible or Underground Power Cable Failures that Disable Accident Mitigation Systems or Cause Plant Transients Below is the Union Electric Company (AmerenUE) response to the Requested Information of NRC Generic Letter 2007-01, "Inaccessible or Underground Power Cable Failures that Disable Accident Mitigation Systems or Cause Plant Transients." The generic letter's "Requested Information" is shown in bold followed by AmerenUE's response.

NRC Requested Information Item (1):

Provide a history of inaccessible or underground power cable failures for all cables that are within the scope of 10 CFR 50.65 (the Maintenance Rule) and for all voltage levels. Indicate the type, manufacturer, date of failure, type of service, voltage class, years of service, and the root causes for the failure.

AmerenUE Response (1):

Research into inaccessible or underground power cable failures at Callaway Plant revealed one failure in power cables within the scope of 10 CFR 50.65 in the voltage range between 480 VAC and 15,000 VAC. Table 1 contains the information requested as well as additional information on failure type, component supported and cable identifier.

Attachment to ULNRC-05415 Page 2 of 3 NRC Requested Information Item (2):

Describe inspection, testing and monitoring programs to detect the degradation of inaccessible or underground power cables that support EDGs, offsite power, ESW, service water, component cooling water and other systems that are within the scope of 10 CFR 50.65 (the Maintenance Rule).

AmerenUE Response (2):

AmerenUE performs a limited amount of insulation resistance and polarization index testing on selected cables during routine motor circuit evaluation testing, overhaul or maintenance of the equipment they feed. AmerenUE has not implemented other inspection, testing or monitoring programs to detect the degradation of inaccessible or underground power cables.

AmerenUE performs the following actions on a routine basis to eliminate or minimize conditions known to impact cable degradation rates for cables that are within the scope of 10 CFR 50.65:

11 Periodically perform visual inspection for corrosion and degradation of cable tray supports for selected cables.

0 Periodically inspect and dewater selected manholes.

Attachment to ULNRC-05415 Page 3 of 3 Table 1. AmerenUE Inaccessible or Underground Power Cable Failures Failure Type Cable Type Cable Type Type of Service Voltage Class Root Causes for (inservice/ (Insulation (Shielded, Cable Date of (energized/ Component Voltage Class (nominal (cable rating Years of Service the Failure Failure # testing) Type) Yes/No) Manufacturer Failure deenergized) Supported Cable Identifier service voltage) voltage) Prior to Failure (apparent cause)

I Inservice Ethylene No Anaconda Exact date Energized during low UHS sump 6EFGI3PA 480V 600V Approx 6 years Unknown. Details are propylene (Durasheath EP) unknown, temperature heater SEF02D limited for this non-insulation with Identified on operations only safety job. Failed cable Hypalon jacket 1/7/1990 suspected of being subjected to excessive strain during initial installation which led tc eventual failure.

Identical replacement cables in service for 17 years. Cause is unverified.