S.D. Codified Laws § 46-2A-7.6
If the board determines that unappropriated water has become available from a fully appropriated groundwater source during the five-year review under § 46-2A-7.5, the board shall make the unappropriated water available to the applications being held by the chief engineer based on the priority established in §§ 46-2A-7.2 and 46-2A-7.4. The chief engineer shall process held applications in accordance with the notice provisions pursuant to chapter 46-2A until such time the board determines the groundwater source to again be fully appropriated in accordance with § 46-6-3.1. Any remaining applications shall continue to be held by the chief engineer for future five-year reviews by the board. If there is remaining unappropriated water available after processing all held applications, the remaining unappropriated water is subject to general appropriation as provided by law.
SDCL 46-2A-7.6