SDCL § 37-2-30: Labeling of any gasoline containing oxygenate.

Any gasoline kept, offered, or exposed for sale, or sold, at retail containing two percent or more by volume of any oxygenate or combination of oxygenates shall be identified as to the specific type of oxygenate or combination of oxygenates in the gasoline. The label may consist of any combination of colors and the label may read ethanol, E10, or ethanol blend. This information shall be posted on the upper fifty percent of the dispenser front panel in a position that is clear and conspicuous from the driver's position. The words shall be in a type at least one-quarter inch in height and a width of type of at least one-sixteenth inch stroke.