ML071270171
| ML071270171 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 05/04/2007 |
| From: | Barfield A Entergy Operations |
| To: | Document Control Desk, NRC/NRR/ADRO |
| References | |
| GL-07-001, GNRO-2007/00022 | |
| Download: ML071270171 (4) | |
Text
Entergy Operations, Inc.
P.O. Box 756 Port Gibson. MS 39150 Tel601 437 2800 GNRO-2007/00022 May 4,2007 U. S. Nuclear Regulatory Commission 11555 Rockville Pike Rockville, Maryland 20852-2378 Attention:
Document Control Desk Subject Response to Generic Letter 2007-01 Grand Gulf Nuclear Station Docket No. 50-416 License No. NPF-29
References:
- 1.
NRC Generic Letter 2007-01, dated February 7, 2007 "Inaccessible or Underground Power Cable Failures that Disable Accident Mitigation Systems or Cause Plant Transients" (GNRI-2007/00014)
NEI letter from J. H. Riley to Administrative Points of Contact dated March 16,2007 "Guidance for Response to GL 2007-01 NRC Letter from Michael J. Case, to J. H. Riley dated April 13, 2007, "Response to Nuclear Energy Institute (NEI) Letter Dated March 26, 2007 - Re: Interpretation of Generic Letter (GL) 2007-01, Inaccessible or Underground Power Cable Failures that Disable Accident Mitigation Systems or Cause Plant Transients."
- 2.
- 3.
Dear Sir or Madam:
Per Reference 1, the NRC issued Generic Letter (GL) 2007-01 to request facilities to submit the following information to the NRC within 90 days of the date of the Generic Letter:
(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 Meintenance 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.
(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).
GO70022
GNRO-2007/00022 Page 2 The response to Question 1 is provided in the attachment to this letter. In researching plant records for the requested information, Grand Gulf used the NEI and NRC guidance provided in References 2 and 3 to clarify the population of cables of interest.
Data bases researched included Plant Condition Reporting System (PCRS), Plant Data Management System (PDMS), and the Maintenance Rule data base. To date, Grand Gulf has experienced one cable failure within the scope of the GL.
In response to Question 2, Grand Gulf does not have preventive maintenance tasks in place to specifically test underground cables. However, some underground cables are periodically tested as part of other electrical equipment testing (i.e. meggering, motor monitoring testing, etc.). Preventive maintenance tasks are in place to periodically test manholes with installed dewatering equipment. Plant condition reporting is used to determine cause and extent of conditions where deemed necessary and would be the mechanism for determining the need for and extent of any increased cable monitoring.
This letter contains no commitments.
If you have any questions or require additional information, please contact Mr. Dennis Coulter at 601-437-6595.
The requested information is being provided pursuant the requirements of 10 CFR 50.54(f). I declare under the penalty of perjury that the foregoing information is true and correct. Executed on May 4, 2007.
Yours truly, Arthur D. Bahield Director, Nuclear Safety Assurance ADB/DMC:dmc
Attachment:
History of Inaccessible or Underground Power Cable Failures within the Scope of 1 OCFR 50.65 for Grand Gulf Nuclear Station cc:
(See Next Page)
GO70022
GNRO-2007/00022 Page 3 cc:
NRC Senior Resident Inspector Grand Gulf Nuclear Station Port Gibson, MS 39150 U. S. Nuclear Regulatory Commission ATTN: Dr. Bruce S. Mallet (w/2)
Regional Administrator, Region 1V 61 1 Ryan Plaza Drive, Suite 400 Arlington, TX 7601 1-4005 U. S. Nuclear Regulatory Commission ATTN: Mr. Bhalchandra Vaidya, NRR/DORL (w/2)
ATTN: ADDRESSEE ONLY ATTN: U. S. Postal Delivery Address Only Mail Stop OWFN/O-7DIA Washington, DC 20555-0001 GO70022 to GNRO-2007/00022 Cable Type Voltage Class History of Inaccessible or Underground Power Cable Failures within the Scope of 10CFR 50.65 for Grand Gulf Nuclear Station Manufacturer BK1 --- 350MCM 1KV 0 koni te Date of Failure
/ Service (Yrs.)
3-1 1-2003 124 years Type of Service 480V Motor Driven Fire pump Apparent Cause
- 1) Age degradation,
- 2) Moisture,
- 3) Possible damage during construction that accelerated I created susceptibility to moisture GO70022