S.D. Codified Laws § 34A-10-2.2
All right and title in any bond or other security required by the Water Management Board or the Board of Minerals and Environment under any provision of this title, Title 45, or Title 46 for the protection of the environment or reclamation of lands or other resources shall be in the state until the board by order releases the security. The bond or other security does not constitute an asset of the person required to provide it, and may not be cancelled, assigned, revoked, disbursed, replaced, or allowed to terminate without board approval. The bond or other security shall be in a form and a reasonable and proper amount approved by the board, and may include a surety bond, escrow account, letter of credit, trust, guarantee, or cash deposit. The board may permit the use of financial assurance other than a bond, including company net worth considerations. Interest earned on any bond or deposit made under § 34A-10-2.1 shall be returned annually to the person required to provide the bond.
SDCL 34A-10-2.2