ML19318C290

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Forwards IE Info Notice 80-23, Loss of Suction to Emergency Feedwater Pumps. No Written Response Required
ML19318C290
Person / Time
Site: Peach Bottom  Constellation icon.png
Issue date: 05/29/1980
From: Grier B
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To: Daltroff S
PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
References
NUDOCS 8007010310
Download: ML19318C290 (1)


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UNITED STATES 8

NUCLEAR REGULATORY COMMISSION o

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REGION I 04 g

631 PARK AVENUE 4,*****,e KING OF PRUSSIA. PENNSYLVANIA 19406 May 29, 1980 Docket Nos. 50-277 50-278 Philadelphia Electric Company ATTN:

Mr. S. L. Daltroff Vice President Electric Production 2301 Market Street Philadelphia, Pennsylvania 19101 Gentlemen:

The enclosed IE Information Notice No. 80-23, " Loss of Suction To Emergency Feedwater Pumps", is forwarded to you for information.

No written response is required.

If you desire additional information regarding this matter, please contact this office.

Sincerely, ht o e H. Grier

' rector

Enclosures:

1.

IE Information Notice No. 80-23 2.

List of Recently Issued IE Information Notices CONTACT:

E. G. Greenman (215-337-5267) cc w/encls:

W. T. Ullrich, Station Superintendent

^

Troy B. Conner, Jr., Esquire Eugene J. Bradley, Esquire Raymond L. Hovis, Esquire Michael J. Scibinico, II, Assistant Attorney General 8007010310

f ENCLOSURE 1 UNITED STATES SSINS No.:

6835 NUCLEAR REGULATORY COMMISSION Accession No.:

OFFICE OF INSPECTION AND ENFORCEMENT 8005050061 WASHINGTON, D. C.

20555 IE Information Notice No. 80-23 Date:

May 29, 1980 Page lof 1 1

LOSS OF SUCTION TO EMERGENCY FEEDWATER PUMPS Description of Circumstances:'

On April 7, 1980, Arkansas Nuclear One Unit 2, suffered a loss of offs.:te power duetotornadodamageto500kvtransmIssiontowers.

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.

Ap mately 15 minutes after the unit tripped, both EFW pumps lost suction. proxi-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 steam.

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 i

pump.

In addition, the EFW suction valve from the Startup and Blowdown Demineralizers will be nrified 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 to their facilities.

No specific action or response is requested at this i

time.

If NRC evaluations so indicate, further licensee actions may be requested or required.

i No written response to this IE Information Notice is required.

If you have l

any questions regarding this matter,.please contact the Director of the appropriate NRC Regional Office.

m ENCLOSURE 2 IE Information Notice No. 80-23 Date:

May 29, 1980 Page 1 of 1 1

RECENTLY ISSUED IE INFORMATION NOTICES Information Subject Date Issued to Notice No.

Issued 80-15 Axial (Longitudinal) 4/21/80 All Power Reactor Facil-Oriented Cracking in ities with an Operating Piping License (OL) or Construc-tion Permit (CP) 80-16 Shaft Seal Packing 5/5/80 All Power Reactor Facil-Causes Binding in Main ities with an OL or CP Steam Swing Check and Isolation Valves 80-17 Potential Hazards 5/5/80 All Radiographic Licensees Associated With Interchangeable Parts On Radiographic Equipment 80-18 Possible Weapons 5/5/80 All Power Reactor Faci-i Smuggling Pouch lities with an OL, Fuel Fabrication and Processing Facilities and Materials Priority I Licensees 80-19 NIOSH Recall of Recir-5/6/80 All Power Raactors with an cclation-Mode (Closed-OL, Research Reactors, Fuel Circuit) Self-Contained Facilities and Priority I Breathing Ap aratus Material Licensees (Rebreathers 80-20 Loss of Decay Heat Re-5/8/80 All Power Reactor Faci-moval Capability at lities with an OL or CP Davis-Besse Unit 1 While in Refueling Mode 80-21 Anchorage and Support 5/16/80 All Power Reactor Faci-of Safety-Related lities with an OL or CP Electrical Equipment 80-22 Breakdown in Contamin-5/28/80 All Power Reactor Facili-ation Control Systems ties with an OL