How to create an alert for any group addition, modification, or deletion in a specific OU.

How to create an alert for any group addition, modification, or deletion in a specific OU.

We need to be alerted when a group is added, deleted or modified within a specific OU.  I know there are pre-configured alerts for groups where the scope is the entire domain, but I need to limit this scope to specific OUs.  Has anyone done this?  Any help is appreciated.