ML19254D067
| ML19254D067 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 09/25/1979 |
| From: | Ziemann D Office of Nuclear Reactor Regulation |
| To: | Counsil W CONNECTICUT YANKEE ATOMIC POWER CO. |
| References | |
| TASK-07-03, TASK-08-02, TASK-7-3, TASK-8-2, TASK-RR NUDOCS 7910220314 | |
| Download: ML19254D067 (3) | |
Text
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UNITED STATES e-
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NUCLEAR REGULATORY COMMISSION g
WASHINGTON, D. C. 20555 v
September 25, 1979 Docket No. 50-213 Mr. W. G. Counsil, Vice President Nuclear Engineering and Operations Connecticut Yankee Atomic Power Company Post Office Box 270 Hartford, Connecticut 06101
Dear Mr. Counsil:
RE: HADDAM NECK PLANT Wc 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 loss of offsite power events have occurred at Haddam Neck Plant on April 27, 1968, July 15,1968, January 19, 1974, and June 26, 1976. To complete our review of loss of offsite power events we require the adcitional infomation concerning the plant offsite grid indicated in the enclosure to this letter.
Please provide your response to the attached questions for the Haddam Neck Plant within 90 days of receipt of this letter.
Sincerely, C/ W $ 5
- q Dennis L. Ziemann, Chief Operating Reactors Branch #2 Division of Operating Reactors
Enclosure:
Request for Additional Infomation cc w/ enclosure:
See next page9k Obk (D P 79do2203ti
Mr. W. G. Counsil September 25, 1979 CC Day, Berry & Howard Counselors at Law One Constitution Plaza Hartford, Connecticut 06103 Superintendent Haddam Neck Plant RFD #1 Post Office Box 127E East Hampton, Connecticut 06424 Mr. James R. Himmelwright Northeast Utilities Service Company P. O. Box 270 Hartford, Connecticut 06101 Russell Library 119 Broad Street Middletown, Connecticut 06457 1194 065
k ENCLOSURE REQUEST FOR ADDITIONAL INFORMATION LOSS OF 0FFSITE POWER A. For losses of offsite power where less than all offsite power was lost: 1. How many circuit's to the offsite network are normally available and how many were lost during the event? 2. What was the cause cf 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 details, 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 partial recovery? Please give details. 2. If turbine trip occurred, how soon after did loss 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 experienced just prior to or during the outace? If so, please give details, voltages reached, affects, etc. 5. Was any frequency decay experienced just prior to or during the outace? If so, please give details, lowest frequency reached, decay rate, affects on equipment o;eration, etc. 6. Date of Event. C. Were there any other less of offsite power events other than we have listed.? If so, please give details of each event. 1g94 066}}