After you delete an email, it is moved to your trash. After 30 days, or if you empty your trash or delete the message from your trash, it will be permanently deleted and CAN NOT be recovered. Brown's IT Service Center has no tools to recover deleted email, and Google's support can not recover deleted email either. 

An exception is a subset of Brown accounts which are set up with the Postini archiving service. You would have been notified when this was set up.