Semantic search

The station commenced an inventory of sources in December 2005. Two sources were missing and are still unaccounted for. The licensee suspects that the sources were thrown away in radioactive trash. The two Americium-241 sources were 0.025 microCuries and 0.026 microCuries. The sources were purchased in 1981 and had since been retired from use and placed in storage. The licensee will notify the NRC Resident Inspector.

• * * UPDATE FROM C. BLAIR TO W. GOTT ON 2/10/06 AT 1415 * * *

This is a RETRACTION to Event # 42283. At 1210 CST on 01/23/2006, Cooper Nuclear Station determined that two Americium-241 sources were missing and could not be located. One source is 0.025 microCuries, the other source is 0.026 microCuries. The 10 CFR 20 Appendix C quantity for Americium-241 is 0.001 microCuries. Each missing Americium-241 source is greater than 10 times the Appendix C quantity but less than 1000 times the Appendix C quantity. The sources were originally acquired in 1981 as internal calibration sources in a complete Stabilized Assay Meter, (SAM-2) for counting air samples in the Emergency Operations Facility (EOF). In August 1999 the SAM-2s were no longer needed in the EOF and were taken inside the radiological controlled area for storage. During the 2005 inventory the sources were discovered missing. 10 CFR 30 provides regulations for licensing byproduct material. 10 CFR 30.15 identifies quantities of certain isotopes that are exempt from the requirements of parts 20, 30 through 36, and 39 of title 10 CFR. 10 CFR 30.15(a)(9)(iii) provides a quantity of 0.05 microCuries of Americium-241 as being an exempt quantity for an internal calibration source in an ionizing radiation measuring instrument. Both of the missing sources were smaller than 0.05 microCuries and thus exempt from the requirements of 10 CFR 20. Since the sources are exempt from the requirement to be licensed and thus exempt from the requirements of 10 CFR 20 this event is not reportable. This has no impact on the operating plant. The licensee will notify the NRC Resident Inspector. Notified NMSS (G. Morell) and R4DO (A. Gody). THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. This source is not amongst those sources or devices identified by the IAEA Code of Conduct for the Safety & Security of Radioactive Sources to be of concern from a radiological standpoint. Therefore is it being categorized as a less than Category 3 source.