Event Notification Report for July 13, 2007

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THIS IS NOT A NEW REPORT.

This event report was originally withheld from public release under the NRC's policy for protecting sensitive unclassified information. The NRC has reevaluated this policy and is now making this event report available to the public with suitable redactions.
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UNATTENDED VACUUM CLEANER IROFS

"On July 13, 2007 at approximately 8:00 a.m., in the Recovery Area Specialty Fuels Facility (SFF), a concern regarding an unattended Raschig ring vacuum cleaner with no top and hose attached was brought to the attention of the SFF foreman. The vacuum cleaner was in the Conversion Area which is part of the Container Control Area (CCA). The vacuum cleaner is used to collect spills and for general cleaning purposes. The vacuum cleaner was filled with Raschig rings to the level of the side mounted hose connection in accordance with procedure. Removal of the top created a free space of approximately [DELETED] in diameter by [DELETED] deep above the hose connection that contained no Raschig rings. With the hose connected and in an upright position, a volume of approximately [DELETED] was created, in violation of the NCS Posting. Solution could have collected in the vacuum cleaner, filling the Raschig ring portion of the vacuum cleaner and the free space above the rings before spilling onto the floor. The foreman immediately removed the hose from the vacuum cleaner and subsequently notified Safety Management. The top was placed back on the vacuum cleaner.

"Evaluation of the Event

"Although the configuration of the unattended vacuum cleaner (no top with hose attached) created a potential unfavorable geometry in the CCA, there was no immediate safety concern. Uranium [DELETED] materials were not being processed in the area at the time and have not been processed in the area for approximately 2 years. Although there is a sprinkler system overhead, there are no other lines containing uranium [DELETED] solutions in the immediate area. The vacuum cleaner drum was sampled and found to contain [DELETED] of liquid with a concentration of less than [DELETED] grams 235U per liter. Considering that the vacuum cleaner was partially full, an additional [DELETED] liters of solution would have been necessary to fill the vacuum cleaner above the Raschig rings, which is a significant accumulation that would likely have been identified by area personnel. The liquid in the drum would also have served to dilute any solution added to the vacuum cleaner. The combined effect of these as found conditions was such that a criticality was highly unlikely.

"This event is bounded by existing scenarios in our ISA. The scenario deals with an [DELETED] Recovery Container Entry Requirements. Specifically, the scenario addresses [DELETED liters that is filled with uranium [DELETED] solution. The scenario credits the following controls as IROFS [Item Relied On For Safety].

"1. [DELETED].
"2. [DELETED].

"The first IROFS was degraded for this event to occur. The second IROFS was not compromised. As a result double contingency was lost."

The licensee will notify the NRC Resident Inspector.

* * * UPDATE ON 05/11/08 BY H. Crouch * * *

THIS IS NOT A NEW REPORT.

This event report was originally withheld from public release under the NRC's policy for protecting sensitive unclassified information. The NRC has reevaluated this policy and is now making this event report available to the public with suitable redactions.
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