PNO-IV-99-023, on 990419,RSO for Raytheon Engineers & Construtors Notified NRC Region IV Ofc of Incident Involving Source Disconnect That Occurred at Oil Refinery Temporary Jobsite.Licensee Continuing Investigation & re-enactments
| ML20206B314 | |
| Person / Time | |
|---|---|
| Site: | 03034231 |
| Issue date: | 04/23/1999 |
| From: | Brown R, Linda Howell NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| References | |
| PNO-IV-99-023, PNO-IV-99-23, NUDOCS 9904290208 | |
| Download: ML20206B314 (2) | |
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, , April 23,1999 ;
PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PNO-IV-99423 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. The information is as initially received without verification or {
evaluation, and is basically all that is known by Region IV staff in Arlington, Texas on this date.
Facility Licensee Emeroency Clasalfication Raytheon Engineers & Constructors Notification of Unusual Event Temporary Jobsite On St. Croix Alert 9433 Kirt>y Drive Site Area Emergency Houston, Texas 77054 - General Emergency Dockets: 03034231 X Not Applicable
' License No: 42-30336-01
Subject:
INDUSTRIAL RADIOGRAPHY SOURCE DISCONNECT On April 19,1999, the radiation safety officer (RSO) for Raytheon Engineers and Constructors notified the NRC Region IV office of an incident involving a source disconnect that occurred at an oil refinery, a temporary jobsite, on St. Croix, U.S. Virgin Islands.
Additional information concoming this incident was subsequently provided to Region IV on April 22,1999.
On April 18,1999, a Raytheon radiographer and a radiographer's assistant were conducting radiographic operations utilizing an AEA Technologies QSA, Inc. Model 660 exposure device containing an iridium-192 source of approximately 59 curies. For this particular work, the setup required that the source guide tube be positioned in a near vertical orientation.
After completing a set of exposures, the radiographer and assistant retracted the source but noticed the automatic locking mechanism would not engage. After an unsuccessful attempt at jiggling the lock mechanism, the radiographer attempted to crank the source out and back in again The locking mechanism would still not engage. Following consultation with the on-site supervisor, the radiographer removed the source guide tube, inserted the safety plug, and the exposure device was moved to a parking lot for further examination.
The on-site supervisor subsequently re-attached the source guide tube and positioned it in a horizontal orientation. The supervisor attempted to crank out the source into the collimator and retum it to a shielded position; however, he too noted that the locking mechanism did not engage. Surveys of the exposure device revealed radiation levels of approximately 200 milliroengton per hour. Realizing the source was still in the guide tube, the supervisor lifted the collimated end of the guide tube up, using a set of 12 inch pliers, allowing the source to slide toward the camera. The supervisor next attempted to remove the source guide tube to verify the position of the source, and he observed what he believed to be the drive cable extending from the outlet port of the device. The supervisor realized that the source was not fully shielded because his alarm ratemeter was activated and a survey still indicated high radiation levels. The source guide tube was reconnected to the exposure device, and the supervisor and radiographer moved the device to the bed of a truck and relocated to a more isolated area at the refinery. After positioning the device and source guide tube on the ground, the supervisor removed the guide tube and pushed the source back into the 1
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, ,. PNO-IV-99-023 t exposure device using a set of pliers. It was later concluded the that the cable observed by
- the supervisor when he first attempted to fully remove the guide tube was most likely the source pigtail. Once the drive controls were disconnected from the exposure device, the
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radiographer and supervisor identified a failure of the drive cable connector. The drive cable has since been forwarded to the licensee's Houston, Texas office for examination.
l Both the radiographer's and supervisor's pocket dosimeters went off-scale. Film badges wom by the radiographer, his assistant and the supervisor were sent for emergency processing. Results received from the dosimetry vendor on April 22,1999, indicated doses l- of 600,290 and 100 millirems for the radiographer, supervisor and assistant, respectively.
The licensee is continuing its investigation and is conducting re-enactments.
l Region IV has coordinated with Region ll, and Region ll dispatched two inspectors to St.
Croix. They will be onsite at the refinery on April, 23,1999. Region IV plans to conduct an inspection at the licensee's Houston office to examine the drive cable and evaluated the licensee's investigation. I NMSS and the State of Texas have been informed. This information has been discussed with the licensee and is current as of 4:30 p.m. April 22,1999.
Contact:
Robert A. Brown Linda Howell (817)860-8130 (817)860-8213 i
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