Minn. Stat. § 103E.281

The engineer shall make a soil survey if: (1) the drainage authority orders a soil survey; (2) the commissioner requests a soil survey; or (3) the engineer determines a soil survey is necessary. The soil survey must show the nature and character of the soil in the proposed drainage project area and include the engineer's findings from the soil survey. The report on the soil survey must be included in the detailed survey report or reported and filed separately before the final hearing.