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On Saturday November 14, 2009 at approxima … On Saturday November 14, 2009 at approximately 0730 there was a heated high pressure release from the 5A/5B UF6 cylinder in the CDL facility Sublimation Station 3. At the time of the upset, the operators were in the process of preparing the cylinder for sublimation. They had just satisfactorily performed the valve leak checks (SOP 409 Section 56 step 5.3) and were performing the cylinder pressure test (SOP 409 Section 56 step 5.4). The cylinder was not being heated. The upset occurred when the cylinder valve was opened (step 5.4.7) to vent the cylinder to column 1D01. The release ruptured the connective teflon tubing that was enclosed in braided stainless steel. When flame was observed the operator actuated the CO2 release valve and extinguished the flame. The subsequent damage appears to be limited to: 1). Braided teflon tubing, 2). Singed area on lexan cover of the enclosure, 3). Possible leak on the inlet and outlet side of the eductor.</br>Of note, column 1D01 was filled with DI water in preparation for startup. The solution should have a clear appearance but has been discolored by the upset. It appears to have been blackened, possibly from burning Teflon.</br>As of 1200 PM the following actions have been taken to place the system in a safe condition:</br>1. Building 333 personnel were notified of the event and the 301/333 door was posted with caution.</br>2. Immediate area is roped off.</br>3. All involved personnel have received incident report forms for completion.</br>4. A firewatch has been posted (ISA requirement as cylinder contains >7.2 kgs UF6)</br>5. Supervisor verified valves on UF6 cylinder are shut.</br>6. Nasal smears taken on all affected personnel (7 dpm max; below action limit of 90).</br>7. High volume air sample taken with no elevated activity identified.</br>8. Area sampled for HF with a Draegor Tube (negative).</br>9. Verified no increase on room CAM (continuous air monitor).</br>10. Subsequent NCS (nuclear criticality safety) evaluation identified no concerns or NCS reportability issues.</br>11. System has been locked out of service with operational locks and appropriate signage placed on sublimation station #3.</br>12. Solution on the floor from the enclosure P traps has been cleaned up.</br>13. The enclosure overflow traps have been filled.</br>14. The CO2 gage has been verified functional and operations personnel are in the process of replacing the spent CO2 cylinder.</br>15. NDA has scanned the NaF trap (no elevated levels found).</br>16. Plant Superintendent took photos of equipment damage.</br>17. HP verified no damage to gloves.</br>18. Sublimation station #1 & 2 have been tagged 'Not Authorized for Use.'</br>19. All proper notifications made.</br>20. Plant Superintendent is in the process of developing a timeline of events.</br>No actual exposures occurred to the workers, the public, and environment. Potential UF6 exposure to workers. However, no loss of containment occurred.</br>No other structures, systems, or equipment components in the area were affected. Safety systems are operational.</br>All sublimation stations have been taken out-of-service pending investigation results.</br>The event is terminated. No declared emergency class.</br>Notifications were made to the local county Emergency Management Coordinator and the Town of Erwin Fire Department.</br>The NRC Resident Inspector has been notified.nt.
The NRC Resident Inspector has been notified.
12:30:00, 14 November 2009 +
45,497 +
18:43:00, 14 November 2009 +
12:30:00, 14 November 2009 +
On Saturday November 14, 2009 at approxima … On Saturday November 14, 2009 at approximately 0730 there was a heated high pressure release from the 5A/5B UF6 cylinder in the CDL facility Sublimation Station 3. At the time of the upset, the operators were in the process of preparing the cylinder for sublimation. They had just satisfactorily performed the valve leak checks (SOP 409 Section 56 step 5.3) and were performing the cylinder pressure test (SOP 409 Section 56 step 5.4). The cylinder was not being heated. The upset occurred when the cylinder valve was opened (step 5.4.7) to vent the cylinder to column 1D01. The release ruptured the connective teflon tubing that was enclosed in braided stainless steel. When flame was observed the operator actuated the CO2 release valve and extinguished the flame. The subsequent damage appears to be limited to: 1). Braided teflon tubing, 2). Singed area on lexan cover of the enclosure, 3). Possible leak on the inlet and outlet side of the eductor.</br>Of note, column 1D01 was filled with DI water in preparation for startup. The solution should have a clear appearance but has been discolored by the upset. It appears to have been blackened, possibly from burning Teflon.</br>As of 1200 PM the following actions have been taken to place the system in a safe condition:</br>1. Building 333 personnel were notified of the event and the 301/333 door was posted with caution.</br>2. Immediate area is roped off.</br>3. All involved personnel have received incident report forms for completion.</br>4. A firewatch has been posted (ISA requirement as cylinder contains >7.2 kgs UF6)</br>5. Supervisor verified valves on UF6 cylinder are shut.</br>6. Nasal smears taken on all affected personnel (7 dpm max; below action limit of 90).</br>7. High volume air sample taken with no elevated activity identified.</br>8. Area sampled for HF with a Draegor Tube (negative).</br>9. Verified no increase on room CAM (continuous air monitor).</br>10. Subsequent NCS (nuclear criticality safety) evaluation identified no concerns or NCS reportability issues.</br>11. System has been locked out of service with operational locks and appropriate signage placed on sublimation station #3.</br>12. Solution on the floor from the enclosure P traps has been cleaned up.</br>13. The enclosure overflow traps have been filled.</br>14. The CO2 gage has been verified functional and operations personnel are in the process of replacing the spent CO2 cylinder.</br>15. NDA has scanned the NaF trap (no elevated levels found).</br>16. Plant Superintendent took photos of equipment damage.</br>17. HP verified no damage to gloves.</br>18. Sublimation station #1 & 2 have been tagged 'Not Authorized for Use.'</br>19. All proper notifications made.</br>20. Plant Superintendent is in the process of developing a timeline of events.</br>No actual exposures occurred to the workers, the public, and environment. Potential UF6 exposure to workers. However, no loss of containment occurred.</br>No other structures, systems, or equipment components in the area were affected. Safety systems are operational.</br>All sublimation stations have been taken out-of-service pending investigation results.</br>The event is terminated. No declared emergency class.</br>Notifications were made to the local county Emergency Management Coordinator and the Town of Erwin Fire Department.</br>The NRC Resident Inspector has been notified.nt.
The NRC Resident Inspector has been notified.
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00:00:00, 18 November 2009 +
SNM-124 +
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23:24:57, 24 November 2018 +
18:43:00, 14 November 2009 +
0.259 d (6.22 hours, 0.037 weeks, 0.00852 months) +
12:30:00, 14 November 2009 +
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