ML19318C156
| ML19318C156 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 05/29/1980 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Crouse R TOLEDO EDISON CO. |
| References | |
| NUDOCS 8007010116 | |
| Download: ML19318C156 (1) | |
Text
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UNITED STATES 3
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GLEN ELLYN,lLLINolS 60137 o
3ocket No. 50-346 WAY 2 9 20 Toledc Edison Company ATTN:
Mr. Richard P. Crouse Vice President Nuclear Edison Plaza 300 Madison Avenue Toledo, OH 43652 Gentlemen:
Thir, Information Notice is forwarded for information. No written re-sponse to this Information Notice is required.
If you have any questions related to this matter, please contact this office.
Sincerely,
'b James G. Keppler Director
Enclosure:
IE Information Notice No. 80-23 cc w/ enc 1:
Mr. T. Murray, Station Superintendent Central Files Director, NRR/DPM Director, NRR/ DOR PDR Local PDR NSIC TIC Harold W. Kohn, Power Siting Commission Helen W. Evans, State of Ohio 0070h
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UNITED STATES SSINS No.:
6835
'k NUCLEAR REGULATORY COMMISSION Accession No.:
OFFICE OF INSPECTION AND ENFORCEMENT 8005050061 WASHINGTON, D. C.
20555 May 29, 1980 IE Information Notice No. 80-23 L'JSS OF SUCTION TO EMERGENCY FEEDWATER PUMPS Description of Circumstances:
On April 7, 1980, Arkansas Nuclear One, Unit 2, suffered a loss of offsite power due to tornado damage to 500 kv transmission towers.
The unit tripped from 98%
power; the diesel generators started and supplied vital loads; natural circula-tion in the reactor coolant system was established; and the emergency feedwater (EFW) pumps supplied feedwater to the steam generators.
The suction of the EFW pumps was aligned to the Condensate Storage Tanks (CST) and to the Startup and Blowdown Demineralizer effluent in parallel.
Approxi-mately 15 minutes after the unit tripped, both EFW pumps lost suction.
Prompt operator action was taken to isolate the EFW pump suction from the Startup and Blowdown Demineralizer and to vent the EFW pumps.
EFW flow was re-established within one minute.
Investigation revealed that the EFW pump suction loss was caused by flashing in the main feedwater train forcing hot water through the Startup and Blowdown Demineralizers to the EFW pump suction where it flashed to cteam.
The steam caused cavitation of the EFW pumps, and the pressure in the EFW suction header prevented flow from the CST.
The licensee has submitted Licensee Event Report No. 50-368/80-18/03L-0, dated May 5, 1980, describing this event.
Action to prevent recurrence included revising the EFW system operating procedure and the Plant Startup Procedure to require shutting the EFW suction valve from the Startup and Blowdown Demineralizers during plant startup at about 5% full power after the steam generator feedwater source has been shifted to a main feedwater pump.
In addition, the EFW suction valve from the Startup and Blowdown Demineralizers will be verified closed once per shift during Mode 1 operation.
This IE Information Notice is provided as an early notification of a possibly significant matter that is still under review by the NRC staff.
It is expected that recipients will review the information for possible applicability i
to their facilities.
No specific action or response is requested at this time.
If NRC evaluations so indicate, further licensee actions may be requeste or required.
I No written response to this IE Information Notice is required.
If you have any questions regarding this matter, please contact the Director of the appropriate NRC Regional Office.
4 15InformationNoticeNo.80-23 Enclosure May 29, 1980 RECENTLY ISSUED IE INFORMATION NOTICES Information Subject Date Issued To Notice No.
Issued 80-22 Breakdown In Contamination 5/28/80 All power reactor Control Programs OLs and near term cps 80-21 Anchorage and Support of 5/16/80 All power reactor Safety-Related Electrical facilities with an Equipment OL or CP 80-20 Loss of Decay Heat Removal 5/8/80 All light water reactor Capability at Davis-Besse facilities holding Unit 1 While in a Refueling power reactor OLs or cps Mode 80-19 NIOSH Recall of Recircu-5/6/80 All holders of a power lating-Mode (Closed-Circuit) reactor OL, Research Self-Contained 8reathing Reactor License, Fuel Apparatus (Rebreathers)
Cycle Facility License and Priority I Material License 80-18 Possible Weapons Smuggling 5/5/80 All power reactor Pouch facilities with an OL, fuel fabrication and processing facilities and M terials Priority I h
licensees (processors and distributors) 80-17 Potential Hazards Associated 5/5/80 All radiography With Interchangable Parts Licenses On Radiographic Equipment
)
80-16 Shaft Seal Packing 4/29/80 All power reactor Causes Binding In Main facilities in your Steam Swing Check And Region with an OL or CP Isolation Valves 80_-15 Axial (Longitudinal) 4/21/80 All Light Water Reactor Oriented Cracking In Facilities holding power Piping reactor OLs or cps
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