The following report was received via e-mail:
At 1310 [PST] on February 11, 2010, the C.Y. Geotech Radiation Safety Officer [RSO] reported that one of the nuclear density gauges (CPN, MC-1DRP, MD90905316 containing 10 milliCurie of Cesium 137 and 50 milliCurie of Americium-241:Be) had been run over by a truck at a construction site. Los Angeles County Radiation Management responded to the scene and found that although the source rod was broken and the plastic case was broken into pieces, the Cesium 137 and the Americium-241:Be sources were still in the shielded body of the device and were intact. There was no contamination. The highest dose rate on the body of the device housing the sources was 9 mR/hr and at one foot was 0.9 mR/hr. The gauge was placed into 2 plastic bags and was placed into the transportation case. The licensee will deliver the gauge to Maurer Technical Services (a licensed CPN representative) who will then ship the gauge to CPN for disposal. [The RSO] reported the gauge user walked about 10 feet away from the gauge to report his test results to a job supervisor and this is when the gauge was run over. The RHB-Brea office will cite the licensee for failure to maintain adequate control over the gauge. The licensee has been instructed they need to provide [California Radiation Control Program] with a report within 30 days as required by regulation. The licensee states they will retrain all of the gauge users regarding the control of the gauge to avoid a similar incident in the future.
Event Location: 951 25th Street, Santa Monica, CA
California Event Number: 021110