I have a problem with an undo tablespace that keeps growing. there are no transactions - I have stopped and started the instance to make sure. But for the last few months it just keeps getting bigger. it is a development instance only but it is staring to become critical. Undo_retention is set to the default of 10800. Does anyone have any ideas on what I could check. I am a sole charge DBA so I there is no one here to ask.

Thanks