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During the excavation of the burial pits a … During the excavation of the burial pits area the licensee has requirements that 2 people survey the excavated materials. Excavated material was placed into a 5 gallon plastic container. After placing the material into the container a reading is taken on the bottom of the container in counts per minute which is then equated to a gram level (mass) of material present. If the mass of material is less than 15 grams (about 300,000 counts per minute) then no criticality safety controls are required. </br>One container, packed to a level of 325,000 counts per minute, was put aside briefly near a waste bin where those materials requiring no controls can be placed. Both people assigned to the work mistook this container for a container requiring no controls. A level of 325,000 counts per minutes equates to a mass of 20 grams of Uranium 235. At that level this item was far from the amount of material needed for a criticality accident but additional controls were required. </br>When the personnel realized their mistake they took that container to another area for overpack into a drum that provides additional spacing needed to provide additional criticality safety protection. At this time the container has the appropriate level of controls. The amount of material present was small enough that it could not have caused a criticality accident.</br>* * * RETRACTION ON 7/4/12 AT 1556 EDT FROM KEVIN DAVIS TO DONG PARK * * *</br>Retraction of the initial notification is appropriate since subsequent, more detailed surveys via gamma spectroscopy (ISOCS) (In Situ Object Counting System) determined that only 2.83g of U-235 were present in the 5 gallon container. The subsequent, more detailed survey was conducted on 6/28/12, after the initial notification was made. This mass quantity is below the threshold for being exempt from criticality safety controls (i.e., no more than 15 g of U-235 in a 5L or larger container). Thus, an unsafe condition was not present when the container was set aside without safety controls since no safety controls are required for 2.83g of U-235 in a 5 gallon container. Based on this retraction, a written report will not be submitted to NRC.</br>The container was retrieved and the container was placed in a drum with a safety collar that provides additional spacing needed to provide additional criticality safety protection. The cause of the event was personnel inattention to the procedure, which contained the correct numerical decision points and controls. Personnel were retrained, particularly on: (a) Independence of redundant surveys and reviews; (b) Use of the procedure to provide numerical setpoints and action steps. Management and independent oversight of burial pit work activities are emphasizing independence of redundant surveys/reviews and use of the procedure.</br>Notified R3DO (Daley), R2DO (Bonser), IRD (Marshall), and NMSS (Damon) via email.RD (Marshall), and NMSS (Damon) via email.
20:30:00, 26 June 2012 +
48,048 +
17:16:00, 26 June 2012 +
20:30:00, 26 June 2012 +
During the excavation of the burial pits a … During the excavation of the burial pits area the licensee has requirements that 2 people survey the excavated materials. Excavated material was placed into a 5 gallon plastic container. After placing the material into the container a reading is taken on the bottom of the container in counts per minute which is then equated to a gram level (mass) of material present. If the mass of material is less than 15 grams (about 300,000 counts per minute) then no criticality safety controls are required. </br>One container, packed to a level of 325,000 counts per minute, was put aside briefly near a waste bin where those materials requiring no controls can be placed. Both people assigned to the work mistook this container for a container requiring no controls. A level of 325,000 counts per minutes equates to a mass of 20 grams of Uranium 235. At that level this item was far from the amount of material needed for a criticality accident but additional controls were required. </br>When the personnel realized their mistake they took that container to another area for overpack into a drum that provides additional spacing needed to provide additional criticality safety protection. At this time the container has the appropriate level of controls. The amount of material present was small enough that it could not have caused a criticality accident.</br>* * * RETRACTION ON 7/4/12 AT 1556 EDT FROM KEVIN DAVIS TO DONG PARK * * *</br>Retraction of the initial notification is appropriate since subsequent, more detailed surveys via gamma spectroscopy (ISOCS) (In Situ Object Counting System) determined that only 2.83g of U-235 were present in the 5 gallon container. The subsequent, more detailed survey was conducted on 6/28/12, after the initial notification was made. This mass quantity is below the threshold for being exempt from criticality safety controls (i.e., no more than 15 g of U-235 in a 5L or larger container). Thus, an unsafe condition was not present when the container was set aside without safety controls since no safety controls are required for 2.83g of U-235 in a 5 gallon container. Based on this retraction, a written report will not be submitted to NRC.</br>The container was retrieved and the container was placed in a drum with a safety collar that provides additional spacing needed to provide additional criticality safety protection. The cause of the event was personnel inattention to the procedure, which contained the correct numerical decision points and controls. Personnel were retrained, particularly on: (a) Independence of redundant surveys and reviews; (b) Use of the procedure to provide numerical setpoints and action steps. Management and independent oversight of burial pit work activities are emphasizing independence of redundant surveys/reviews and use of the procedure.</br>Notified R3DO (Daley), R2DO (Bonser), IRD (Marshall), and NMSS (Damon) via email.RD (Marshall), and NMSS (Damon) via email.
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00:00:00, 4 July 2012 +
SNM-33 +
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>.
23:16:12, 24 November 2018 +
17:16:00, 26 June 2012 +
-0.135 d (-3.23 hours, -0.0192 weeks, -0.00442 months) +
20:30:00, 26 June 2012 +
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