ML20005G124

Responds to Violations Noted in Exam Rept 50-326/OL-89-01. Corrective Action:Use of Lower Ranges of Linear Channel Will Be Fully Investigated & Mode Switch Electrical Transients Will Be Cleaned & Examined

ML20005G124
Person / Time
Site:	University of California - Irvine
Issue date:	12/18/1989
From:	Geoffrey Miller CALIFORNIA, UNIV. OF, IRVINE, CA
To:	Kirsch D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
Shared Package
ML20005G123	List: ML20005G124
References
NUDOCS 9001180160
Download: ML20005G124 (2)

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. DEPARTMENT of CHEMISTRY IRvlNE. CALIFORNIA 92717

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NUCLEAR REACTOR FACILITY 9h supervisor: DR. o.E. MILLER

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TEL:(714) 856-6649 oR 714 856 6082 --

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U.S. Nuclear Regulatory Commission, December 18th, Itygg

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.1450 Maria Lane, Suite 210, Walnut Creek, CA 945%.

Attention: D.F. Kirsch, Chief, Reactor Safety Branch Docket: 55 326 Licensee resoonse to NRC reonest dated November 28th.1989 Gentlemen:-

. The following is submitted in response to the referenced request, the subject of which was

' " Examination Report",

1. Deficiencies noted during this examination:

There are two specific deficiencies noted in the written report from the examiner. One or two other items were discussed orally but did not appear m the report.

(a) Use oflower ranges of the linear channel.

This will be fully investigated as oart of our routine annual maintenance which is currentiv underway.

I intend that this be irsolved so that the lower ranges can again be used during start ups.

(b) Mode switch electrical transients.

When switching between STEADY STATE and AUTOMATIC mode, the mode switch has occasionally introduced electrical transients that have resulted in reactor scrams over the last l 20 years. This switch is crucially making and breaking a large number of contacts in a "make before break" style. The wafer switch onl reliability no matter how perfect is its condition.y does this with a certain degree of Considering the very large number of cycles used with this switch, its reliability is generally very good.,lt does seem to respond better with a firm rather than a nervous hand, which is not surprismg in view of the above strict "make before break" requirements. This feature does seem to result in a greater

. percentage of occurrences with inexperienced operators in the past, we have had some

, success with both cleaning, and replacing, this switch, in terms of reducing the frequenev of electrical transient introduction. We have never reduced the frequency per year to zero.

In recent months, this switch has not shonn any problem in the hands of experienced operators, hence my comments to the examiner at the time.

This switch will be cleaned and examined aa part of our annual console maintenance being conducted at this time.

9001180160 900105 PDR ADOCK 05000326 V

PDC NRC Maintenance Response Page 1 12/18/89 1

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2. General Comments:

There is no doubt that facilities such as ours have only a limited budget for routine and non-routine maintenance and other activities (see National Academy of Sciences mpon on Research Reactor Facilities). As a result, for some years, we have had to prioritize maintenance activities to emphasize those items most closely associated with direct safety issues. For a TRIGA reactor, operating at 250 kilowatts, this means that personnel health physics matters have a higher pnority. Reactor items, while a nuisance to operaton; and operations, can, in general, not be classified as having any direct impact on the hazard level

- the TRIGA has just too much intrinsic safety. As a reminder, even if all the engineered safety systems fail, this reactor will continue to be perfectly safel This may be difficult for those associated with other types of facility to believe, or accept, but it happens to be true.

The above comments should not be taken to represent a cavalier attitude on my pan, merely a statement to establish the relative degree of concem that should be demonstrated.

ALL maintenance deficiencies will he addressed. Attendance to known deficiencies will be accomplished during the present maintenance cycle and operations will not be resumed until these have been " cured" or at least properly addressed with foreseeable resolution in the future.

Suspension of operations for a period is obviously of concern to customers and may drive potential customers to seek resources elsewhere, however it may be the only way to assure your office that we are not improperly operating the facility. This does not, of course, preclude new issues from arising in the next year.

Since there is no chance that a new control system will be possible for this facility (the cost is totally prohibitive), we will have to manage with 1950-1960's technologies, and the problems (or advantages) that those have. The only reasonable alternative may be closure and decommissioning. It would be sad if a desire to achieve a level of perfection of operating reliability at what is otherwise a usable and perfectly safe facility were to drive us more rapidly to closure.

Sincerely,

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George E. Miller Reactor Supervisor cc: Reactor Operations Committee members l

NRC Maintenance Response Page 2 12/18/89 l

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