S.D. Codified Laws § 3-9-2.2
The State Board of Finance may authorize a meal expense reimbursement at the per diem rate to any agency, state officer, or employee conducting state business at an event extending entirely through a meal time without interruption, regardless of whether the attending officer or employee is away from his or her place of residence or headquarters station. The reimbursement request may be made by an agency representative, state officer, or employee only if the attending officer's or employee's participation in the event is approved by the head of the officer's or employee's department or office and if the event includes provision of a meal for which the agency, officer, or employee is billed.
The authorization shall be made on a form prescribed by the Governor. A certification of the approval of the department or office head shall accompany the claim filed pursuant to § 3-9-8.
SDCL 3-9-2.2