A reasonable level of operational control is present to avoid routine transfer of solution to
the final Special Process area trap in the northwest area of Room 1022.
Significant solution bypass of the final trap would require gross system misoperation for
the transfer efforts to F-1202, coupled with either alarm failure or lack of personnel response to
the alarm. In the Headhouse, the final wet vacuum equipment provides a significant safe
geometry surge volume (multiple 6-inch diameter steel traps in parallel), as discussed in CSA HH-
123, followed by two alarmed 6-inch glass traps in series. Upon liquid detection by these final
alarms, automatic block valves in the main vacuum header close to prevent fissile solution transfer
to the jet vacuum producers. This alarm system and interlocked block valve is formally
designated as a safety system. The surge volume plus safety system serve to positively preclude
loss of geometry control fissile solution, by preventing loss of fissile material to the storm sewer
Use of an improper container for drainage of solution from F-1202 is precluded by
operator training and supervisory oversight.
A situation whereby an operator intentionally transfers fissile solution from F-1202 into a
large geometry container is precluded by the strict nature of operator training and supervisory
oversight for this process area. Operator training emphasizes the immediate danger of such
action. Such an event would be expected only as the result of either sabotage or suicidal action,
which are outside the bounds of the analysis.
The distribution trap is approved for use as described.