S.D. Codified Laws § 34A-16-3
The governing body of the regional recycling and waste management district shall consist of commissioners elected or appointed as specified in the proposed articles of incorporation. The commissioners of the regional recycling and waste management district shall be composed solely of elected officials from the local governments that are included in the district. There shall be at least one commissioner from each county or fraction thereof. The names of the initial board of commissioners shall be designated in the articles of incorporation. The initial commissioners' terms shall be at least one year, and shall end on December thirty-first of the year during which a general election is held. The articles of incorporation may provide for the appointment of additional commissioners to represent areas that may be added to the district pursuant to § 34A-16-9. The addition of any new municipality or county may not be deemed an amendment to the articles of incorporation of the district. The total number of commissioners in a district shall be established in the articles of incorporation. The terms of commissioners who are first elected shall be: at least one-half but no more than sixty percent of the commissioners for terms of four years, and the remainder of the commissioners for terms of two years. Except for the commissioners first elected or appointed, all commissioners shall be elected or appointed for terms of four years each. However, if a vacancy occurs other than by expiration of a term, the district board shall fill the unexpired term by appointment. Each commissioner shall hold office until his successor has been elected or appointed and has qualified.
SDCL 34A-16-3