South Dakota Codified Laws
Chapter 29 - Emergency Location Of State Government
Section 1-29-2 - Validity of official acts at emergency capital.

1-29-2. Validity of official acts at emergency capital.
During such time as the seat of government remains at such emergency temporary location, or locations, all official acts now or hereafter required by law to be performed at the seat of government by any officer, agency, department, or authority of this state, including the convening and meeting of the Legislature in regular, extraordinary, or emergency session, shall be valid and binding when performed at such emergency temporary location, or locations, as if performed at the normal location of the seat of government.

Source: SL 1961, ch 287, ยง2.