As long as he has proof of his identity (I.e. birth certificate, passport) he can get a replacement. If he doesn't have one of these items please go to the www.dds.ga.gov site to review the lost or stolen replacement list. The fee is $5.00 to replace a lost or stolen identification card.
You can get a copy of it online via the DDS website if he has an account. If this is an older ID that is pre-RealID then he needs to order a copy of his birth certificate, have proof of residency such as a phone bill or utility bill, obtain a copy off his social security card and/or verification of social security statement, and bring all that in - it's good for him to have his own personal copies of all identifying documents anyways.
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