ENS 46055
ENS Event | |
|---|---|
01:35 Jun 29, 2010 | |
| Title | Agreement State Report - Moisture Density Gauge Destroyed in Fire |
| Event Description | The following report was received via fax from the State of Wisconsin:
On June 28, 2010 at 20:35 the Department of Health Services (DHS) on-call State Radiological Coordinator (SRC) was informed that there had been a fire involving two trailers at the Dodge Concrete Ready Mix plant, W6298 US Hwy 18, Jefferson, WI. One of the trailers contained a Troxler 3440 portable moisture density gauge owned by Tetra Tech, a Wisconsin Radioactive Materials Licensee who was performing licensed activities at the concrete plant. The gauge contains a maximum of 9 milliCuries of Cesium-137 and 44 milliCuries of Americium-241:Beryllium as radioactive sealed sources. The original call to the DHS 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> emergency hotline was made by the Tetra Tech Radiation Safety Officer (RSO). The SRC subsequently received a page from the Wisconsin Emergency Management (WEM) Duty Officer at 20:45. The Duty Officer explained to the SRC that he had been informed of a fire in Jefferson, (WI) involving two burning trailers involving radioactive material. The SRC informed the duty officer that DHS intended on following up on the incident and would provide additional information. The SRC then contacted the licensee RSO. The RSO was at the scene of the fire interacting with the fire department. He (RSO) indicated that a fire had consumed two of their job trailers at Dodge Ready Mix and that one trailer contained a portable gauge which housed both a Cs-137 and an Am-241/Be radioactive source. The RSO indicated that radiation surveys around the trailer indicated radiation levels of less than 1 mR/hr around the burned trailer containing the gauge. After the RSO proposed his course of action to the SRC, they agreed that it was unsafe to attempt to extract the gauge from the trailer in the dark. The RSO cordoned off the trailer with yellow "Caution-Do Not Enter" tape pending an attempt to extract the gauge the following morning. All of the licensee's proper radiation postings and equipment were also destroyed in the fire. All postings and labels on the gauge transport container and the gauge itself were destroyed. DHS informed the RSO that they would arrive at the scene of the fire the next morning to supervise the extraction and provide technical radiation safety support. DHS investigators arrived at Dodge Ready Mix in Jefferson, Wl at 09:30. The Tetra Tech RSO and Authorized Users (AU) were present. Both trailers were completely destroyed by the fire and the gauge housing, transport case and associated equipment were melted together and fused to the trailer floor. The melted plastic, gauge and trailer housing had to be removed as a block. The maximum radiation level was ~8 mR/hr near contact with the Cs-137 shielding, which appeared to be intact. The radiation levels indicated that the shielding for both sources had retained its integrity. Contamination wipes were taken on the source rod, source shielding and the source exit point. No evidence of contamination was found. The DHS investigators were informed that the fire department had moved the trailers away from the site garage to reduce the risk of the fire spreading. All debris, trailers and trailer sites were surveyed. No elevated radiation levels were found. These surveys gave the DHS investigators and RSO confidence that the source remained in the fully shielded position. After consulting with Troxler, the gauge manufacturer, the RSO decided to remove the melted plastic and debris from the gauge remnants so it could be transported and shipped back to Troxler in a standard transport case. The licensee succeeded in removing the debris and melted plastic and at 12:45 was able to package the gauge in the Type-A transport container for return to their office in Wausau. The gauge was to be leak tested prior to shipment to Troxler for disposal. All debris removed from the gauge and the gauge itself was surveyed for contamination and radiation levels. The maximum radiation level remained at ~8 mR/hr and no evidence of contamination was found. The transport index was consistent with what the RSO typically finds with an intact gauge. Event Report ID: WI100011 |
| Where | |
|---|---|
| Tetra Tech, Inc Jefferson, Wisconsin (NRC Region 3) | |
| License number: | 073-1165-01 |
| Organization: | Wisconsin Radiation Protection |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+15.75 h0.656 days <br />0.0937 weeks <br />0.0216 months <br />) | |
| Opened: | Kurt Pedersen 17:20 Jun 29, 2010 |
| NRC Officer: | Eric Simpson |
| Last Updated: | Jun 29, 2010 |
| 46055 - NRC Website | |
Tetra Tech, Inc with Agreement State | |
WEEKMONTHYEARENS 460552010-06-29T01:35:00029 June 2010 01:35:00
[Table view]Agreement State Agreement State Report - Moisture Density Gauge Destroyed in Fire 2010-06-29T01:35:00 | |