A member who has completed at least five consecutive years of membership service in the public schools of Georgia or the University System of Georgia immediately prior to applying may obtain up to ten years of creditable service for service as a teacher in a private elementary or secondary school or any private college or university located in the state accredited by the Southern Association of Colleges and Schools, the Georgia Accrediting Association, or a nationally recognized accrediting agency by the State Board of Education. Such service credit shall be allowed on the basis of one year of credit for such service for each additional year of membership service in the public schools of Georgia or the University System of Georgia. A member wishing to obtain such creditable service shall provide documentation and pay to the board of trustees such amount as determined by the actuary as necessary to grant such benefit without creating any accrued actuarial liability as to this retirement system.