05000409/LER-1979-019, Forwards LER 79-019/01T-0

Forwards LER 79-019/01T-0

ML20125B945
Person / Time
Site:	La Crosse File:Dairyland Power Cooperative icon.png
Issue date:	12/26/1979
From:	Linder F DAIRYLAND POWER COOPERATIVE
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20125B947	List: 05000409/LER-1979-019, Forwards LER 79-019/01T-0
References
LAC-6711, NUDOCS 7912310497
Download: ML20125B945 (2)

LER-2079-019, Forwards LER 79-019/01T-0

Event date:
Report date:
4092079019R00 - NRC Website

text

..

c HAIRYLAND POWEN COOPERATIVE Ba Groue, QYiwondn 54601 December 26, 1979 _

In reply, please refer to LAC-6711 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 CRCSSE BOILING WATER REACTOR (LACBWR)

PROVISIONAL OPERATING LICENSE NO. DPR-45 REPORTABLE OCCURRENCE NO. 79-19

References:

(1) LACBWR Technical Specifications, Section 3.2.9.a.3 (2) LACBWR Technical Specifications, Section 5. 2.1. 2.b

Dear Mr. Keppler:

In acccrdance with Reference 1, this is to inform you of abnormal degradation discovered in the primary reactor containnent during  ;

periodic Type 2 surveillance leakage rate testing.

A Type B penetration leakage rate test to determine the leakage rate of the Containment Building emergency airlock was performed on December 23, 1979. The results of the test did not meet the accep-tance cri':eria as specified in Reference 2. The test leakage rate was determined to be 1.0372 SCFH and the acceptance criteria is 0. 749 SCFH. *

• Shall not exceed 2% of leakage rate Lpo, where L po is 37 46 SCFH l

Since the inner door of the emergency airlock provided a leak-tight closure, containment integrity was not jeopardized by the observed deficiency. The reactor was in Operating Condition No. 1 - Power Operation - at the time of the test.

An investigation was conducted promptly to determine the source of leakage. The problem was traced to a leak in the mechanical seal of

~

the interior door operating shaft which extends through the airlock i shell to the outside (See Figure 1). Two 0-rings and the 90000009

~ *~

~ [$[N1..N. s 7912310 c

I

Mr. James G.-Keppler,-Reg. Dir. . LAC-6711 December 26, 1979-U. S.. Nuclear Regulatory Commission shaft packing were found to be flat (See Figure 2). A new seal was installed and.the Type B leak rate test was reperformed with zero leakage observed.

'At the present time, the shaft seals are not replaced on a scheduled basis. Replacement of-the shaft seals will be added to the scheduled preventive maintenance on the emergency airlock to prevent future occurrences of.this type.*

"rompt notification of this event was made to Region III, U. S.

Nuclear Regulatory Commission, at 0650 on December 23, 1979. The event was also discussed with Mr. 2idgway at 0800 on December 23, 1979.

A Licensee Event Report (

Reference:

Appendix A, Regulatory Guide 1.16, Revision 4) is enclosed.

If you have any questiens concerning this report, please centact us.

Very truly yours, DAIRYLisND POWER COOPERATIVE Frank Linder, General Manager FL:LG:af Enclosures cc: Director, Office of Inspection and (30)

Enforcement U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Director, Office of Management Information (3) and Program Control U. S. Nuclear Regulatory Commission Washington, D. C. 20555 1

• No prior incidents related to degradation of the emergency air-lock shaft seals have been recorded.

90000010 ofvw2ogoS].

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