ML19260C540
| ML19260C540 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 12/18/1979 |
| From: | Linder F DAIRYLAND POWER COOPERATIVE |
| To: | |
| References | |
| NUDOCS 8001070381 | |
| Download: ML19260C540 (2) | |
Text
. =,
DS6 DAIRYLAND POWER COOPERATIVE Ba Groue, Onsconsin 54601 December 18, 1979 In reply, please refer to LAC-6691 DOCKET NO. 50-409 Mr. James G.
Keppler Regional Director U.
S.
Nuclear Regulatory Commission Directorate of Regulatory Operations Region III 799 Roosevelt Road Glen Ellyn, Illinois 60137
SUBJECT:
DAIRYLAND POWER COOPERATIVE LA CROSSE BOILING WATER REACTOR (LACBWR)
PROVISIONAL OPERATING LICENSE NO. DPR-45 REPORTABLE OCCURRENCE NO. 79-18
References:
(1)
LACBWR Technical Specifications, Section 3.9.2.a.9.
(2)
LACBWR Technical Specifications, Section 4.2.1.6.
Dear Mr. Keppler:
In accordance with Reference (1), this is to inform you of components that require remedial action to prevent operation in a manner less conservative than assumed in the accident analyses in the Safety Analysis Report or Technical Specification bases.
On December 14, 1979, LACBWR received notification from Allis-Chalmers Manufacturing Co. that the plant's containment isolation dampers as they are presently installed in the ventilation system, require repositioning from full open to an opening of not more than 250 to better ensure quick full closure at the maximum containment vessel pressure of 52 psig which would be approached as a result of the maximum credible accident.
This nor.ification came as a result of Allis-Chalmers' conclusions based on a series of dynamic flow tests of geometrically prototypical models recently completed at an independent research laboratory.
Upon receiving notification by Allis-Chalmers, corrective action was taken to close the containment isolation dampers during reactor cperation until such time as the dampers are permanently modified to permit opening no greater than 250 The containment building is currently being vented continuously through the 4" vent header.
1696 114 cP[I o DEC 26 tem
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n Mr. James G.
Keppler, Regional Director LAC-6691 U. S. Nuclear Regulatory Commission December 18, 1979 Prompt notification of this event was made to Mr. Licitra of Region III, U.
S. Nuclear Regulatory Commission, at 1830 on December 14, 1979.
Authorization for this written confirmation to be submitted beyond the first working day following knowledge of the reportable event was granted to L. Goodman by Mr. Schoules on Monday, December 17, 1979.
Should you have any questions regarding this report, please contact us.
Very truly yours, DAIRYLAND POWER COOPERATIVE
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Frank Linder, General Manager FL:LG:af cc:
Director, Office of Management Information and Program Control U.
S.
Nuclear Regulatory Commission Washington, D.
C.
20555 1696 115