(1) This Code section shall apply only to those members who have eight or more years of creditable service under this chapter;

(2) Prior service credit for military service under this Code section may be obtained under a ratio of one year of credit for military service for each five years of creditable service, not considering creditable service under this Code section, or, for military service of less than a full year, under a ratio of credit for one month of military service for each five months of creditable service;

(3) No prior service credit for military service may be obtained under this Code section if credit for such military service has been or may be obtained under any other provision of this chapter;

(4) No prior service credit for military service may be obtained under this Code section if such military service has been or may be used in the determination of the member's eligibility for retirement benefits or allowances under any other state retirement or pension system, any retirement or pension system of a political subdivision, or any federal retirement or pension program, except social security and those retirement programs covered under Public Law 810, 80th Congress, as amended;

(5) The total amount of prior service credit for military service may not exceed five years for all military service which is creditable as prior service under this chapter; and

(6) The member must pay to the board of trustees the regular employee contribution of 7 1/2 percent of compensation based on the compensation received by members of the General Assembly during legislative sessions at the time the military service was rendered plus interest on such employee contributions at the rate of 7 percent per annum compounded annually from the time the military service was rendered until the date of payment.