(40 ILCS 5/13-304) (from Ch. 108 1/2, par. 13-304)
    Sec. 13-304. Optional plan of additional benefits and contributions made through December 31, 2002.
    (a) While this plan is in effect, an eligible employee may establish additional optional credit for additional benefits by electing in writing at any time to make additional optional contributions. The employee may discontinue making the additional optional contributions at any time by notifying the Fund in writing.
    Employees first entering service after June 30, 1997 are not eligible to participate in the plan established under this Section.
    (b) Additional optional contributions for the additional optional benefits shall be as follows:
        (1) For service after the option is elected, an additional contribution of 3% of salary
    
shall be contributed to the Fund on the same basis and under the same conditions as contributions required under Section 13-502.
        (2) For service before the option is elected, an additional contribution of 3% of the
    
salary for the applicable period of service, plus interest at the annual rate as shall from time to time be determined by the Board, compounded annually from the date of service to the date of payment. All payments for past service must be paid in full before credit is given. A person who has withdrawn from service may pay the additional contribution for past service at any time within 30 days after withdrawal from service, so long as payment is made in full before the retirement annuity commences. No additional optional contributions may be made for any period of service for which credit has been previously forfeited by acceptance of a refund, unless the refund is repaid in full with interest at the rate specified in Section 13-603, from the date of refund to the date of repayment. Nothing herein may be construed to allow an additional optional contribution to be made on the account of a deceased employee.
    (c) Additional optional benefit shall accrue for all periods of eligible service for which additional contributions are paid in full. The additional benefit shall consist of an additional 1% of average final salary for each year of service for which optional contributions have been paid, to be added to the employee's retirement annuity as otherwise computed under this Article. The calculation of these additional benefits shall be subject to the same terms and conditions as are used in the calculation of the retirement annuity under this Article. The additional benefit shall be included in the calculation of the automatic annual increase in annuity under Section 13-302(d), and in the calculation of surviving spouse's annuity where applicable. However, no additional benefits will be granted which produce a total annuity greater than the applicable maximum established for that type of annuity in this Article. The total additional optional benefit that may be received under this Section is 15% of average final salary.
    (d) Refunds of additional optional contributions shall be made on the same basis and under the same conditions as provided under Section 13-601.
    (e) Optional contributions shall be accounted for in a separate Optional Contribution Reserve.
    (f) The tax levy computed under Section 13-503 shall be based on employee contributions including the amount of optional additional employee contributions.
    (g) Service eligible under this Section may include only service as an employee as defined in Section 13-204, and subject to Section 13-401 and 13-402. No service granted under Section 13-801 or 13-802 shall be eligible for optional service credit. No optional service credit may be established for any military service, or for any service under any other Article of this Code. Optional service credit may be established for any period of disability paid from this Fund, if the employee makes additional optional contributions for such period of disability.
    (h) This plan of optional benefits and contributions shall not apply to service prior to withdrawal rendered by any former employee who re-enters service unless such employee renders not less than 36 consecutive months of additional service after the date of re-entry.
    (i) The effective date of this optional plan of additional benefits and contributions shall be the date upon which approval was received from the Internal Revenue Service, July 31, 1987.
    (j) This plan of additional benefits and contributions shall expire December 31, 2002. No additional contributions may be made after that date, and no additional benefits will accrue after that date.
    (k) The maximum optional benefits for current and prior service for which an employee can make contributions in a single year shall be limited to 15 years of service in 1997 and before; 9 years of service in 1998; 6 years of service in 1999; and 3 years of service in 2000, 2001, and 2002. No person may establish additional optional benefits under this Section for more than 15 years of service.
(Source: P.A. 92-599, eff. 6-28-02.)