I’ve been attending meetings of the Texas Low Level Radioactive Waste Disposal Compact Commission (TLLRWDCC, possibly the least useful acronym ever devised) over the last couple of years. This is the Commission that has oversight for applications for shipments of waste to the newly constructed radioactive waste dump in Andrews County in west Texas. Many of the applicants want to ship “sealed sources,” which are radioactive materials used in medicine, oil drilling and fracking and in a vary of industrial tests. One common thread in applicants’ testimony is that sealed sources very seldom leak, and are relatively safe to dispose of.
Those assurances were called into question recently, when the Arizona Radiation Regulatory Agency notified the Nuclear Regulatory Commission of an incident concerning Phoenix Raytheon Missile Systems in which two of Raytheon’s sealed sources recently failed leak tests. The Agency summarized the event to the NRC:
…the licensee had wipe test results which indicated that two of the Americium-241 sealed sources they possessed are leaking or contaminated. Each Am-241 sealed source has 3 solid metal foils of Am-241 with an activity of 2.1 mCi for each foil, for a total activity of 6.3 mCi for each source. The failed leak test, which showed 0.022 microCuries of removable contamination, occurred on April 19, 2012, but was not reported to the Agency until September 19, 2012. The second failed leak test occurred on source number 003 on September 19, 2012. It was previously installed in a positive mode ion mobility spectrometer where an engineer viewed signs of corrosion on the source. A subsequent leak test showed 0.92 microCuries of removable contamination.
You can find Event Reports on the NRC web page at http://www.nrc.gov. This one in Event Number 48356.