Any public hospital which has withdrawn from participation in the Employees’ Retirement System is hereby authorized to pay any cost-of-living increases granted by law, including but not limited to the 1985 and 1988 cost-of-living increases, to any retiree of the Employees’ Retirement System who was employed by any such public hospital and who was a member of the Employees’ Retirement System pursuant to Section 36-27-6 during such employment.