O.C.G.A. § 36-36-113 (2019)

(a) The county governing authority may by majority vote object to the annexation because of a material increase in burden upon the county directly related to any one or more of the following:

(1) The proposed change in zoning or land use;

(2) Proposed increase in density; and

(3) Infrastructure demands related to the proposed change in zoning or land use.

(b) Delivery of services may not be a basis for a valid objection but may be used in support of a valid objection if directly related to one or more of the subjects enumerated in paragraphs (1), (2), and (3) of subsection (a) of this Code section.

(c) The objection provided for in subsection (a) of this Code section shall document the nature of the objection specifically providing evidence of any financial impact forming the basis of the objection and shall be delivered to the municipal governing authority by certified mail or statutory overnight delivery to be received not later than the end of the thirtieth calendar day following receipt of the notice provided for in Code Section 36-36-111.

(d) In order for an objection pursuant to this Code section to be valid, the proposed change in zoning or land use must:

(1) Result in:

(A) A substantial change in the intensity of the allowable use of the property or a change to a significantly different allowable use; or

(B) A use which significantly increases the net cost of infrastructure or significantly diminishes the value or useful life of a capital outlay project, as such term is defined in Code Section 48-8-110, which is furnished by the county to the area to be annexed; and

(2) Differ substantially from the existing uses suggested for the property by the county’s comprehensive land use plan or permitted for the property pursuant to the county’s zoning ordinance or its land use ordinances.