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100  +
This is a non-emergency notification regarThis is a non-emergency notification regarding an extremely small amount of Special Nuclear Material (SNM) which is unaccounted for. On 6/21/2012, it was determined that two nuclear instrumentation incore detectors could not be accounted for at Catawba. Detectors of this type are used to measure incore neutron flux (intensity of neutron radiation) inside the reactor vessel. This determination was made following the completion of a scheduled inventory of nuclear instrumentation incore detectors in storage. This is being reported under 10 CFR 20.2201(a)(1)(ii) (reports of theft or loss of licensed material).</br>According to Catawba documentation, there should be 54 such detectors in storage. Only 52 detectors could be physically located on site. There is no evidence of theft or diversion of these detectors. According to site documentation, one or both of the detectors may have been shipped to Barnwell in 1986. Detectors of this type contain very small amounts of Uranium-235 (0.0041 grams/detector), which qualifies them as SNM. The most likely location for the detectors is either in one bunker located on site and within the radiological controlled area or at Barnwell via a low level radioactive waste shipment. The search for these detectors was suspended based on a determination that the additional dose to plant workers involved in the search was not justified by an equivalent offsetting safety benefit. It is unlikely that these detectors could have left the site other than in a radioactive waste shipment as the radiation monitoring equipment in place would likely have identified the presence of the detectors.</br>This event had no effect on plant operations and no impact on public health and safety has been identified. A written report will be made in accordance with 10 CFR 20.2201(b)(1)(i-vi). The licensee will notify the NRC Resident Inspector.</br>Usually, spent incore detectors are stored in a locked high radiation area at the facility. This was the first physical inventory of sources performed by the licensee.</br>THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL</br>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. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf</br>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 sourceg categorized as a less than Category 3 source  
20:00:00, 21 June 2012  +
48,070  +
14:06:00, 5 July 2012  +
20:00:00, 21 June 2012  +
This is a non-emergency notification regarThis is a non-emergency notification regarding an extremely small amount of Special Nuclear Material (SNM) which is unaccounted for. On 6/21/2012, it was determined that two nuclear instrumentation incore detectors could not be accounted for at Catawba. Detectors of this type are used to measure incore neutron flux (intensity of neutron radiation) inside the reactor vessel. This determination was made following the completion of a scheduled inventory of nuclear instrumentation incore detectors in storage. This is being reported under 10 CFR 20.2201(a)(1)(ii) (reports of theft or loss of licensed material).</br>According to Catawba documentation, there should be 54 such detectors in storage. Only 52 detectors could be physically located on site. There is no evidence of theft or diversion of these detectors. According to site documentation, one or both of the detectors may have been shipped to Barnwell in 1986. Detectors of this type contain very small amounts of Uranium-235 (0.0041 grams/detector), which qualifies them as SNM. The most likely location for the detectors is either in one bunker located on site and within the radiological controlled area or at Barnwell via a low level radioactive waste shipment. The search for these detectors was suspended based on a determination that the additional dose to plant workers involved in the search was not justified by an equivalent offsetting safety benefit. It is unlikely that these detectors could have left the site other than in a radioactive waste shipment as the radiation monitoring equipment in place would likely have identified the presence of the detectors.</br>This event had no effect on plant operations and no impact on public health and safety has been identified. A written report will be made in accordance with 10 CFR 20.2201(b)(1)(i-vi). The licensee will notify the NRC Resident Inspector.</br>Usually, spent incore detectors are stored in a locked high radiation area at the facility. This was the first physical inventory of sources performed by the licensee.</br>THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL</br>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. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf</br>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 sourceg categorized as a less than Category 3 source  
Has query"Has query" is a predefined property that represents meta information (in form of a <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Subobject">subobject</a>) about individual queries and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
100  +
00:00:00, 5 July 2012  +
Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
02:03:40, 2 March 2018  +
14:06:00, 5 July 2012  +
false  +
13.754 d (330.1 hours, 1.965 weeks, 0.452 months)  +
20:00:00, 21 June 2012  +
Two Incore Detectors Containing U-235 Unaccounted for During Inventory  +
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