Sec. 11. PREVIOUS FIRE DEPARTMENT SERVICE. (a) Except as provided by Subsection (c) of this section, a person who elects to become a member of a retirement system under an authorization adopted under Subsection (f) of Section 9 of this Act may establish credit in the retirement system for previous service performed for another fire department included within the coverage of a retirement system under this Act. To establish credit for the previous service, the person must deposit with the retirement system an amount determined by the board of trustees that is equal to the sum of:

(1) the amount that the person would have contributed to the system if the person's previous fire department service had been performed for the department by which the person is employed, computed on the member contribution rate in effect in the retirement system at the time the service was performed and on the person's compensation for the previous service; and

(2) interest on the amount described by Subdivision (1) of this subsection at the rate of eight percent, compounded annually, from the date the service was performed to the date of deposit.

(b) If a person makes the deposit described by Subsection (a) of this section, the municipality or other political subdivision served by the fire department that employs the person shall deposit with the retirement system an amount determined by the board that is equal to the sum of:

(1) the amount that the municipality or other political subdivision would have contributed to the system if the person's previous fire department service had been performed for the department by which the person is employed, computed on the contribution rate of the municipality or other political subdivision in effect in the retirement system at the time the service was performed and on the person's compensation for the previous service; and

(2) interest on the amount described by Subdivision (1) of this subsection at the rate of eight percent, compounded annually, from the date the service was performed to the date of deposit.

(c) A person may not establish credit under this section for service that is credited in another public retirement system, including another retirement system subject to this Act.