How to remove an Apple ID "Reachable at" alias.

How do you remove an Apple ID "Reachable at" alias?

For example if the device is a cell phone it likely will have a number and your apple id email. I have an extra one and its an old email that I would like to remove.

I have searched the community forum a little bit to help me with this.

I have come up with no way to remove an alias from an apple id account. I can only add new ones. Hopefully this thread will have the answer to my question.