ML19254D114
| ML19254D114 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 09/18/1979 |
| From: | Ippolito T Office of Nuclear Reactor Regulation |
| To: | Pilant J NEBRASKA PUBLIC POWER DISTRICT |
| References | |
| NUDOCS 7910220391 | |
| Download: ML19254D114 (3) | |
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NUCLEAR REGULATORY COMMISSION 3w i
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,o SEPTEMBER J 8 G79 Docket No. 50-298 Mr. J. M. Pilant, Director Licensing & Quality Assurance Nebraska Public Power District P. O. Box 499 Columbus, Nebraska 6F601
Dear Mr. Pilant:
We are currently reviewing the adequacy of the offsite power systems of nuclear power plants and in particular, the loss of offsite power events at your facility. One aspect of this review concerns the history of experienced total and partial power outages and attendent voltage or frequency conditions of the grid.
In our review of this matter we have drawn upon the infomation provided to us via Licensee Event Reports and followup letters which you have sent to us. Our review of these reports indicated the 1oss of offsite power events have occurred at the Cooper Nuclear Power Station on February 21, 1976. To complete our review of loss of of.' site power events we require the additional infomation concerning the Cooper Nuclear Power Station offsite grid indicated in the enclosure to this letter.
.Please provide your response to the attached questions for the Cooper Nuclear Power Station within 90 days of receipt of this letter.
Sincerely, Thomas / Ippolito, Chief Operating Reactors Branch #3 Division of Operating Reactors
Enclosure:
Reauest for Additional Infomation cc w/ enclosure:
See next page 3
007 3N o
7910220
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Mr. J. M. Pilant eE#IEPSER 8 1979 2-Nebraska Public Power District cc:
Mr. G. D. Watson, General Counsel Nebraska Public Power District P'. O. Box 499 Columbus, Nebraska 68601 Mr. Arthur C. Gehr, Attorney Snell & Wilter 3100 Valley Center Phoenix, Arizona 85073 Cooper Nuclear Station ATTN:
Mr. L. Lessor Station Superintendent P. O. Box 98 Brcwnville, Nebraska 68321 Auburn Public Library 118 - 15th Street Auburn, Nebraska 68305 s
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s REQUEST FOR ADDITIONAL INFORMATION A.
For losses of offsite power where less t'.en all offsite power was lost:
1.
How many circuits to the offsi.t. network are normally available and how many were lost during the evenc?
2.
What was the cause of the event?
3.
Why did the other lines not fail when some did fail?
4.
Was any voltage increase or decrease experienced just prior to or during the outage?.If so, please give 'atails, voltages reached, affects, etc.
5.
Was any frequency decay experienced just prior to or during the outage?
If so, please give details, lowest frequency reached, decay rate, affects on equipment operation, etc.
6.
How long was power unavailable from the circuit?
7.
Date of Event.
B.
For losses of all offsite power:
1.
How long was the power off? How long for par-ial recovery? Please give details.
2.
I' turbine trip occurred, how soon after di.d less of offsite power occur?
3.
If power was recovered promptly (10 minutes or less), was it due to automatic or manual actions?
4.
Was any voltage increase or decrease experier.ced just p:'.or to or during the outage?
If so, please give details,' voltages reached, affects, etc.
5.
Was any frequency decay experienced just prior to or during the outage?
If so, please give details, lowest fcequency reached, decay rate, affects on equipment operation, etc.
6.,
Date of Event.
C.
Were there any other loss of offsite power events other -han we have listed?
If so, please give details of each even'.
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