It's not going to do you any good anyway if the guards scan it at the gate with the portable scanners they use. The trusted agent has probably revoked it since you no longer work for that entity. You'd probably have a bigger problem on your hands trying to get onto the installation without proper authority. Turn it into the CAC office immediately.
No. However, it is a DOD card. However, you will have to get it renewed at your new base on your expiration date located at the top right of your card.