ML20136F970

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Updates Review of Operating Experience from 850117-0415. Event Frequency Compared W/Other BWRs & Pwrs.Event Frequency Higher than Expected,But Significantly Decreased from Preceeding Period.Initiatives Effective
ML20136F970
Person / Time
Site: Limerick, 05000000
Issue date: 04/26/1985
From: Crutchfield D
Office of Nuclear Reactor Regulation
To: Novak T
Office of Nuclear Reactor Regulation
Shared Package
ML20136E841 List:
References
FOIA-85-668 NUDOCS 8505030651
Download: ML20136F970 (4)


See also: IR 05000117/2004015

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APR 2 61985

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MEMORANDUM FOR:

Thomas M. Novak, Assistant Director

for Licensing, DL

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FROM:

Dennis M. Crutchfield, Assistant Director

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for Safety Assessment, DL

,

SUBJECT:

UPDATE OF LIMERICK-1 OPERATING EXPERIENCE

'

This memorandum updates our previous review of operating experience at

Limerick-1. The previous review (memorandum enclosed) included a survey of

reported events at Limerick-1 for the period between October 26, 1984 and

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January 17, 1985. This review update covers the period between January 17,

1985 and April 15, 1985.

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. . . _

'S'urvey of Experience

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In the past three months of the low power license period (i.e. January 17,

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1985 through April 15,1985), twenty-six non-security events have been

reported to the NRC Operations Center per 10 CFR 50.72

In addition,

seventeen Licensee Event Reports (LER) have been filed per 10 CFR 50.73 in

the first one-and one half months of the update period. These figures

translate to a frequency of reported events between nine and twelve events

per month. This reflects a significant reduction from the frequency of

eighteen events per month identified in the first three months of the low

power license period (see attached report).

Limerick event frequencies for

the first and subsequent three month period of the low power license are

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compared with one another and with frequencies for other recently licensed

BWRs and PURs in Table 1.

As in the initial survey period, the vast majority of reported events have

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been inadvertent actuations of emergency safety features principally

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involving the Control Room and Reactor Building Ventilation Isolation

features, and the Reactor Water Clean-up System. Personnel errors played a

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significant role in about one-third of the reported events. This is signifi-

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cantly less than the share involving personnel errors identified in the first

three months of the low power license period, which was a little over

one-half. A breakdown of reported events is presented in Table 2.

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APR 2 61985

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Our review of significant events presented at Operating Reactors Event

Briefings indicates that no Limerick events were discussed 'in the past three

months of the low power license period.

Conclusion

Operating experience at Limerick-1 has been surveyed for the past three

~

months of the low power license period and compared with experience in the

first two and three quarter months of the low power license period and with

similar experience at other recently licensed BWRs and PWRs. The review

indicates that the frequency of reportable events at Limerick is still

somewhat higher than expected during initial start-up, but has decreased

significantly from that observed in the first few months of the low power

license period. Initiatives taken by Region I and the licensee to reduce the

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event frequency appear to be working effectively.

,

This review required approximately 20 manhours to complete.

Y

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Denn

M.

tchfield, Assistant Director

for Safety Assessment, DL

cc:

R. Martin

A. Schwencer

R. Gallo, Reg. I

J. Wiggins, Reg. I

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TABLE 1

RATE OF REPORTED EVENTS AT

TWELVE SELECTED PLANTS

DURING LOW POWER LICENSE PERIOD

Period of Low Power

Rate of Reported Events

~

Operation Studied

(Avg. No. Reports / Months)

Facility

(Months)

50.72

LER**

PWR

Diablo Canyon

5

4

4

McGuire Unit 2

3

1 -2

1-2

Sumer Unit

3

1

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14

Callaway Unit 1

3

9

10

.

Catawba Unit 1

6

5

5

Byron Unit 1

1.5

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15

Waterford ilnit 3

3

7

2

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BWR

Grand Gulf

21

10

18*

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LaSalle Unit 1

4

1

19*

Susquehanna Unit 1

4

3

12

Susquehanna Unit 2

3

2

3

Limerick 1

2.75(1)

18

17

Limerick 1

3(2)

9

12

.

  • Includes data from before 1/1/84,50.73 LER Rule
    • Does not include reports from last 30 days of period due to delay

in reporting

      • Majority of reports are reoccurrence of two particular problems

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(1) Period is from October 26, 1984 to January 17, 1985

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(2) Period is from January 17, 1985 to April 15, 1985

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TABLE ?

BREAKDOWN OF REPORTED EVENTS

AT LIMERICK-1

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No. of Reported Events *

General Category

(10/26/84 - 1/17/85) & (1/17/85 - 4/15/85)

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Technical Specification Violation

8

3

Degradation of Safety Equipment

3

3

Procedural and Operational Errors

0

2

Minor chemical releases

0

2

RPS Actuations

Actual -Chr11enges

0

0

Inadvertent actuations

2

1

. due to personnel error

Inadvertent actuations

3

3

due to equipment problems

ESF Actuations

Actual challenges

0

0

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Ina'dvertent Actuations

due to personnel error

22

4

' ~~

Inadvertent Actuations

due to equipment problems

20

14

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TOTAL

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37

2

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  • This is total number of unique events reports made through either ENS

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(50.72) or LER.

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