S.D. Codified Laws § 46A-10A-107

When the voters vote by ballot to determine whether to form a board of trustees or on the election of trustees, a poll list shall be kept by the clerk of the meeting, on which shall be entered the name of each person whose vote is received. The ballot shall be delivered by the voter to one of the clerks, so folded as to conceal its contents, and the clerk shall deposit the ballot in a box provided for that purpose.