All planning commissions created pursuant to Ga. L. 1957, p. 420, as amended, relating to the creation of planning commissions by certain political subdivisions, are authorized to provide workers' compensation insurance coverage for their employees. Before any such planning commission can provide any such insurance coverage, it shall adopt an appropriate resolution, at any public meeting of the commission, setting forth the procedure for furnishing and maintaining such insurance coverage. From the date of the adoption of such resolution, the planning commission shall be deemed to be an employer and each of its employees to be an employee within the meaning of this chapter; provided, however, that the planning commission may, by appropriate notice to employees and by proper resolution, elect to withdraw from coverage under this chapter.