I think this would depend on how you are adding it.
For a work queue itself, you can go into control room, find your work queue, select all (select row 1, Ctrl + Shift + End), and then right click and "Delete Worked Cases". Anything that is completed or has an exception will be removed from the work queue and it won't reappear until you add it back.
Hope this helps.
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Michael Annis
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