Question:
Is it possible to have two people as managers for one departmental email account?
Answer:
If the email account is a Google Group, then the answer is yes. Managers can add members to the group and assign them the 'manager' role. To do this, log into your Gmail account and navigate to select 'Groups' from the 'Group apps' menu icon in the top right corner (looks like a checkerboard). Click on 'My groups'. Click on Settings > Group settings > Direct add members. Enter email address and a message to recipient. Once the member is added, select All members, then the member name. Click on the Role and from the drop down menu, highlight 'Manager'.
If the email account is an entity account, then you'll just have to make sure all managers are aware of the current password.