ML20136F251
| ML20136F251 | |
| Person / Time | |
|---|---|
| Site: | General Atomics |
| Issue date: | 11/14/1985 |
| From: | Asmussen K GENERAL ATOMICS (FORMERLY GA TECHNOLOGIES, INC./GENER |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 67-8037, NUDOCS 8511220076 | |
| Download: ML20136F251 (3) | |
Text
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In Reply GA Technologies Inc.
Refer To: 67-8037 PO BOX 85608 SAND o oRNIA 9208 14 November 1985
<s 9 Mr. Harold R. Denton Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D.C. 20555
Subject:
Docket No. 50-163: Reactor Facility License R Reportable Occurrence.
Dear Mr. Denton:
On November 7, 1985, the NRC, Region V compliance office was immediately notified by telephone of a reportable occurrence concerning the R-67 TRIGA reac*ar. This letter and attachment constitute the report required by our license within 10 days of such an event. The attachment describes the occurrence wherein the reactor was operated for a period of about one week with one of the two required power level scram channels having a set point about 9% above the Technical Specification limit.
We trust you will find the description of the occurrence and the correc-tive action are appropriate and satisfactory.
If you should have questions, you may contact me at (619) 455-2823, or Dr. W. L. Whittemore at (619) 455-3277.
Very truly yours, Keith E. Asmussen Licensing Administrator KEA:he
Attachment:
11/7/85 Reportable Occurrence, R-67 TRIGA Reactor.
cc:
Mr. James B. Martin, NRC, Reg. V.
8511220076 851114 PDR ADOCK 05000163 t
S PDR
' I 10955 JOHN JAY HOPKINS DR, SAN DIEGO CAUFoRNIA 92121
ATTACHMENT L
November 14, 1985 November 7, 1985 Reportable Occurrence for R-67 TRIGA Reactor Description and Chronology:
'On September 27, 1985, during startup of the Mark F R-67 TRIGA Reactor for long term operation, a power level calibration was performed. Based upon the results of this calibration, the sensitivity, readings at 1.5 Mw, and scram settings (1.65 Mw) were computed for each of the three power level monitoring channels (referred to as K-1, K-2 and K-3 in our system). The values obtained were entered into the logbook and onto stickers for each power level monitor panel.
Settings of the scram levels were made and power was increased to the final operating level of 1.4 Mw.
At this time three scram channels were in operation. The Technical Specifications require only two operable scram channels.
On October 30, 1985, spurious noise signals were observed on channel K-2.
All other channels and instrumentation were functioning normally. The K-2 scram channel was bypassed to prevent a spurious scram. Thus, com-mencing on October 30, 1985, operation continued with the required mini-mum of two operable power level scram channels.
l On November 7,1985, during routine logbook review, an entry error was discovered relative to the September 27, 1985, calibration.
The sensi-tivjgy of the K-3 power monitoring channel was calculated to be 5.05 x
~
10 amp / watt but as a result of an inadv9gtent juxtaposition of numbers was entered into the logbook as 5.50 x 10 amp / watt.
The K-3 scram channel set point was thus based upon an erroneous entry and corresponded to 1.74 Mw.
Thus, during the period of approximately one week from Octo-ber 30, 1985 to November 7,1985, we were in violation of our Technical Specification limit as a result of one of the two power level scram channels being set about 95 higher than the Technical Specification l
limit of 1.65 Mw.
The reactor functioned in a routine uneventful fashion during the entire time and the power level scram channels were never call-ed upon to act.
I Corrective Action:
l l
The erroneous scram set point for channel K-3 was corrected immediately upon discovery of the error on November 7, 1985. A review of the channel K-3 readings (entered in the logbook) indicated that when using the cor-rect sensitivity for this channel, the indicated power level neve i x-ceeded 1.5 Mw.
Mr. John Shoptaugh (a licensed senior operator) reported the above des-l.
cribed events to Mr. Greg Uhas of NRC, Region V, by telephone a*, about 1320 hours0.0153 days <br />0.367 hours <br />0.00218 weeks <br />5.0226e-4 months <br /> on November 7, 1985.
- ** t On November 8, 1985, a procedure. change was instituted which requires a
-second operator to independently perform the power level channel sensi-tivity calculation and to verify that all associated logbook and sticker entries and scram settings are correct.
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l Ic k
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