S.D. Codified Laws § 11-7-86
If the commission finds that the redevelopment is not being carried out or maintained in accordance with the contract terms and conditions, or there is a failure to prosecute the work with such diligence, or to assure its completion on time, it shall notify the purchaser or lessee and, when one exists, the surety in writing of the noncompliance. Unless the purchaser or lessee complies with the terms of agreement within twenty days from the date of such notice, a forfeiture by the purchaser or lessee to the commission shall result, and the commission may take over the work and may cause such work to be done, and, if there be a surety, the cost of the work shall be paid by the surety. The commission may take possession of and utilize in completion of the work such materials, appliances, and plant as may be on the site of the work and necessary therefor. Thereafter, the commission may operate, sell, or lease the completed premises on such terms as are agreeable with it.
SDCL 11-7-86