ML16141A856
| ML16141A856 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 12/19/1994 |
| From: | Wiens L Office of Nuclear Reactor Regulation |
| To: | Hampton J DUKE POWER CO. |
| References | |
| TAC-M88556, TAC-M88557, TAC-M88558, NUDOCS 9412230110 | |
| Download: ML16141A856 (4) | |
Text
December 19, 1994 Mr. J. W. Hampton Vice President, Oconee Site Duke Power Company P. 0. Box 1439 Seneca, SC 29679
SUBJECT:
REQUEST FOR ADDITIONAL INFORMATION REGARDING THE EFFECTS OF EMERGENCY POWER OVERFREQUENCY ON OCONEE UNITS 1, 2, AND 3 (TAC NOS. M88556/M88557/M88558)
Dear Mr. Hampton:
By letter dated August 25, 1994, Duke Power Company (DPC) provided a description of a modification intended to address potential overfrequency scenarios which could occur if an emergency start signal were received when the Keowee hydrogenerators were connected to the network grid. The staff is reviewing this proposed modification as part of the review of the Technical Specification amendment submitted on February 24, 1994, which proposes a surveillance of a modification intended to correct a related single failure vulnerability of the Keowee units. We find that additional information, as indicated in the enclosure, is required to complete our review. You are requested to respond to these questions by January 6, 1995, in order for us to complete our review on schedule. If you have questions regarding this matter, contact me at (301) 504-1495.
This request affects fewer than ten respondents and, therefore, it is not subject to Office of Management and Budget review under P.L.96-511.
Sincerely, Original signed by:
L. A. Wiens, Senior Project Manager Project Directorate 11-3 Division of Reactor Projects-I/II Office of Nuclear Reactor Regulation Docket Nos. 50-269, 50-270 and 50-287
Enclosure:
Request for Additional Information cc w/encl:
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W UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 December 19, 1994 Mr. J. W. Hampton Vice President, Oconee Site Duke Power Company P. 0. Box 1439 Seneca, SC 29679
SUBJECT:
REQUEST FOR ADDITIONAL INFORMATION REGARDING THE EFFECTS OF EMERGENCY POWER OVERFREQUENCY ON OCONEE UNITS 1, 2, AND 3 (TAC NOS. M88556/M88557/M88558)
Dear Mr. Hampton:
By letter dated August 25, 1994, Duke Power Company (DPC) provided a description of a modification intended to address potential overfrequency scenarios which could occur if an emergency start signal were received when the Keowee hydrogenerators were connected to the network grid. The staff is reviewing this proposed modification as part of the review of the Technical Specification amendment submitted on February 24, 1994, which proposes a surveillance of a modification intended to correct a related single failure vulnerability of the Keowee units. We find that additional information, as indicated in the enclosure, is required to complete our review. You are requested to respond to these questions by January 6, 1995, in order for us to complete our review on schedule. If you have questions regarding this matter, contact me at (301) 504-1495.
This request affects fewer than ten respondents and, therefore, it is not subject to Office of Management and Budget review under P.L.96-511.
S' cerely, A. Iiens, Senior Project Manager Project Directorate 11-3 Division of Reactor Projects-I/II Office of Nuclear Reactor Regulation Docket Nos. 50-269, 50-270 and 50-287
Enclosure:
Request for Additional Information cc w/encl:
See next page
Mr. J. W. Hampton Duke Power Company Oconee Nuclear Station cc:
A. V. Carr, Esquire Mr. Ed Burchfield Duke Power Company Compliance 422 South Church Street Duke Power Company Charlotte, North Carolina 28242-0001 Oconee Nuclear Site P. 0. Box 1439 J. Michael McGarry, III, Esquire Seneca, South Carolina 29679 Winston and Strawn 1400 L Street, NW.
Ms. Karen E. Long Washington, DC 20005 Assistant Attorney General North Carolina Department of Mr. Robert B. Borsum Justice Babcock & Wilcox P. 0. Box 629 Nuclear Power Division Raleigh, North Carolina 27602 Suite 525 1700 Rockville Pike Mr. G. A. Copp Rockville, Maryland 20852 Licensing - ECO50 Duke Power Company Manager, LIS 526 South Church Street NUS Corporation Charlotte, North Carolina 28242-0001 2650 McCormick Drive, 3rd Floor Clearwater, Florida 34619-1035 Dayne H. Brown, Director Division of Radiation Protection Senior Resident Inspector North Carolina Department of U. S. Nuclear Regulatory Commission Environment, Health and Route 2, Box 610 Natural Resources Seneca, South Carolina 29678 P. 0. Box 27687 Raleigh, North Carolina 27611-7687 Regional Administrator, Region II U. S. Nuclear Regulatory Commission 101 Marietta Street, NW. Suite 2900 Atlanta, Georgia 30323 Max Batavia, Chief Bureau of Radiological Health South Carolina Department of Health and Environmental Control 2600 Bull Street Columbia, South Carolina 29201 County Supervisor of Oconee County Walhalla, South Carolina 29621
REQUEST FOR INFORMATION OCONEE NUCLEAR STATION - UNITS 1. 2 & 3 KEOWEE OVERSPEED CONDITION FOLLOWING A LOAD REJECTION
- 1.
Please provide a detailed discussion of the effect of frequency and voltage of the electrical power supplied by Keowee to safety-related motors (e.g., ECCS motors) and protective relays during an overspeed/
overfrequency scenario as described in LER 268/93-01, Revision 1. The discussion should describe the exact sequence of events during a postulated overspeed/overfrequency scenario and discuss acceptable voltage and frequency ranges for the power supplied by the Keowee units which ensure ESF systems will function as intended. In your response, please discuss any administrative controls or limits regarding the normal mode operation of the Keowee units needed to ensure the time requirements contained in applicable accident analyses are met. This discussion of a postulated overspeed/overfrequency scenario should include and make reference to any pertinent calculations, analyses, and/or evaluations performed to support your assumptions and conclusions.
Please provide frequency and voltage plots vs. time for the power supplied by the Keowee units during a postulated overspeed/overfrequency scenario and any sensitivity studies conducted to show how frequency and voltage change with different lake levels or different power output levels of the Keowee units. Also, please provide any calculations performed to determine maximum and minimum lake levels for Keowee normal mode operations and the maximum Keowee power output levels permitted at these lake levels to ensure the time requirements contained in applicable accident analyses are met.
- 2.
Please provide any safety evaluation related to the proposed modification to the Oconee Nuclear Station intended to address the overfrequency concern.
ENCLOSURE