(a) Except as provided by this section, a municipality may not terminate participation in the retirement system if the municipality has employees who are members of the system, but the municipality may elect to discontinue the participation in the system of persons employed or reemployed after the date of an election to discontinue.
(b) If before November 1 of any year a municipality gives written notice of its intention to the retirement system, the municipality may terminate coverage under, and discontinue participation in, the supplemental death benefits fund. A termination under this subsection is effective on January 1 of the year following the year in which notice is given.

(c) If a municipality participating in the retirement system has no employees who are members of the system and has no present or potential liabilities as a result of the participation of former employees, the municipality, on receiving a refund under Section 855.319, ceases participation in the system.