Ga. Code § 36-3-5
When all proceedings have transpired pursuant to this article, three copies of the survey and plat evidencing a change in county lines and a copy of a resolution from the governing authority of each county evidencing approval of the change shall be filed jointly by the judge of the probate court of each county with the Secretary of State. Upon receipt of the copies of the survey and plat and the resolutions provided above, the Secretary of State shall certify the survey and plat and send a certified copy thereof to the clerk of the superior court of each county affected by the change in county lines. The clerk of the superior court shall record the survey and plat in the same book in which other plats of the county are recorded. The Secretary of State shall retain one copy of the survey and plat, such copy of the survey and plat to be filed in his office.
OCGA § 36-3-5