ML20010E288
| ML20010E288 | |
| Person / Time | |
|---|---|
| Site: | 05000187 |
| Issue date: | 08/10/1981 |
| From: | Crandall W NORTHROP CORP. |
| To: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| References | |
| 327-81-63, NUDOCS 8109030285 | |
| Download: ML20010E288 (3) | |
Text
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In reply refer to 327-81-63 NORTHROP August 10, 1981 m
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Attention: Director of Inspection and Enforcement 4 N
Subject:
Licensee Event Report
Reference:
(a) Technical Specification for the florthrop Corporation TRIGA riark F Reactor, dated 19 February 1971 Gentlemen:
In accordance with Section H.7.a., of the Technical Specifications for the florthrop Reactor, the following information is submitted for your record.
Certain operations of the florthrop Reactor on 28 July 1981, may have been in violation of paragraph F.3. , of the Technical Specifications. Please refer to the enclosed memo for details.
Region V Director of Inspection and Enforcement was informed by telephone within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of this occurrence.
A copy of this report has been sent to Region V Director of Inspection and Enforcement.
Very truly yours, N E$
Walter E. Crandall, Chairman OA Corporate Radiation Committee Enclosure ,
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Memorandum ( (
Northrop wmat an in reply refer to 327-81-57 w Dan Avant F rom-George Cozens Walt Crandall
- REPORT OF A POSSIBLE ABNORMAI. OCCURRENCE D 28 July 1981 UahH@ Rtf On the morning of 28 July 1981, Joe Woods noticed an unusual sound being emitted by the stack monitor (RMl) pump. The problem was diagnosed as dry bearings in the pump itself.
Grease was applied to the bearings (where the grease fittings could be teached), oil was added to the gear box, the pump was tested briefly, and the system returned to operation by about 0835.
During the day, the stack monitor was left on, in preparation for a reactor run. Due to customer problems, the run was delayed until 1735, at which time a 2Kw, 10 minute steady state run was conducted in the exposure room. Because this run was at such a low level (0. 2% of our maximum steady stat.e level) , little or no increase in the stack monitor reading / recording was expected. Frank Blair, the operator, logged the stack monitor reading as 35 cpm during the run (at 1748). The background for RM1, on the day's startup list was recorded as 35 cpm. (By comparison, RM1 typically reads about 60 cpm for 20Kw runs - or 2% of full power).
At about 1815, after completing the shut down for the day, Frank proceeded to turn off the stack monitor, but found that the pump motor had already stopped. Apparently, the motor had blown its circuit breaker some time earlier. The stack monitor instrumentation, which is on a separate circuit, was still operating.
On the reactor console, located immediately below the RM1 remote meter, are two indicator lights: one, a white light, indicates when there in nlactrical. power on the pump motor: the other. a red 3ight,.
indicates when the gas flow entering the RM1 chamber is insufficiently low. Under normal operating conditions, the white light would be lighted and the red light extingui.shed. Since both lights get their i
power from the motor ci rcuit, both would be off should this circuit lose its power. The operator does not recall the white light being off during the 2Kw run. We believe then, that the stack monitor I pump was operating during the run, and that it stopped operating some time a f ter the run. In t.his case, no violation of our Tech Specs would have occurred.
i l NDRTHRDP
To: Dan Avant Page 2 of 2 Walt Crandall Subj: REPORT OF A POSSIBLE ABNORMAL OCCURRENCE However, in the event that the extinguished white light could have been overlooked, there exists the possibility that some, or all, of the 2Kw run was made with little or no sampling of the stack effluent, in which case, a violation of our Tech Specs would exist. In any case, this situation presented no hazard to Northrop personnel or t.he general public.
A possible solution to prevent any reoccurrences of this kind in the future, might be the installation of a relay to the RM] circuitry, which would alarm if the pump r.otor loses power during operating conditions.
Geor e Co. ens Northrop Reactor