The following information was provided by the
Texas Department of State Health Services [DSHS]:
At approximately 10:00 am, November 30, 2004 a tractor-trailer alarmed radiation monitors with a load of scrap steel at Commercial Metals Austin [CMC - Austin] scrap yard. Earth Tech, Inc. in San Antonio was notified by ThermoMeasuretech for help with a possible source. Commercial Metals confirmed the load triggered a scale-mounted radiation detector at SMI- Texas, Sequin, TX and the [CMC - Austin] driver had returned the load to Commercial Metals-Austin.
Earth Tech contacted [CMC - Austin] warehouse manager and noted that he had indeed isolated the source from the load and that he had roped off a 2 mR/hr barrier around the affected area. He stated that he needed additional instrumentation as his Ludlum model 19 was reading off-scale.
Personnel from the Earth Tech office in San Antonio were deployed with a SAMS unit and a Ludlum model 9. They arrived at [CMC - Austin] at 1:30 pm. Searching through a small amount of soil, an actual source was revealed. The source was found to be a metallic foil disk approximately 1.5 cm. in diameter. The source emissions were found to be nonisotropic, reading high levels on one side and low levels on the other. Once the source was identified and separated from the soil, the SAMS was utilized to identify the radioisotope. The SAMS identified two low-energy photo peaks and identified the source as cadmium-109. However, the spectrum showed an unusually large amount of high-end tailing with a continuum shape similar to that found from sources of high-energy x-rays. The source was shielded and transported to ThermoMeasuretech for further investigation. It was initially presumed the source was possibly an activated foil.
DSHS records for this incident showed the source was 120 microCuries of Cd-109. When CMC was called on 3/8/05 to follow up on the incident, they stated that the source had been later identified as 1 milliCurie of Sr-90. This amount of Sr-90 required immediate notification.
Texas Incident No. I-8187
Due to personnel changes at the
Texas Department of State Health Services and Commercial Metals in late 2004, the initial report to the NRC was delayed.