(a) This Code section shall apply only to counties, county boards and departments of health, and employees of county boards and departments of health of counties of this state having a population of 550,000 or more according to the United States decennial census of 1980 or any future such census.

(b) As used in this Code section, the term:

(1) "Employee" means an employee of a county board or department of health of a county subject to the provisions of this Code section who:

(A) Is a member of a local retirement system; and

(B) Would be eligible for membership in and a member of the Employees' Retirement System of Georgia if employed by a county board or department of health of a county other than a county subject to the provisions of this Code section.

(2) "Local retirement system" means a retirement or pension system maintained by a county which includes as members thereof employees of the county boards or departments of health, and the term includes any such retirement or pension system created by law or created by ordinance or resolution of the county under the home rule provisions of the Constitution of Georgia.

(3) "Salary supplement" means compensation paid from county funds to employees of county boards or departments of health in addition to the compensation paid to such employees from state funds or from state funding sources.

(c) The Department of Human Resources shall make payments to the governing authority of a county subject to the provisions of this Code section to partially reimburse the county for the cost incurred by the county in providing for the membership in a local retirement system of each employee. The amount of the payment for each employee shall be an amount equal to three-fourths of the amount which would be paid by the Department of Human Resources as the employer contribution to the Employees' Retirement System of Georgia if the employee were a member of the retirement system. It is specifically provided, however, that such employer contributions shall be based on state compensation paid to the employee or on the amount paid from state funds to the county as compensation for the employee, and any salary supplement to such compensation shall not be considered in the determination of the amount of the employer contribution.

(d) The reimbursement payments provided for by subsection (c) of this Code section shall be paid for all service by an employee as a member of a local retirement system which is completed after the date that funding of this Code section begins as provided in subsection (f) of this Code section. When such funding begins, such reimbursement payments shall be paid to the county at the same time employer contribution would be paid by the Department of Human Resources to the Employees' Retirement System of Georgia if the employee were a member of the retirement system.

(e) If at any time any employee becomes a member of the Employees' Retirement System of Georgia, the reimbursement payments provided for by this Code section shall cease for that employee on the effective date of membership in the Employees' Retirement System of Georgia.

(f) The payments to a county governing authority provided for by this Code section shall be contingent upon appropriations made by the General Assembly to the Department of Human Resources for the purpose of making such payments. To the extent that the General Assembly appropriates less than the amount necessary to pay the full amount provided for by this Code section, the amount otherwise payable shall be reduced in accordance with the amount actually appropriated by the General Assembly.