SDCL § 37-2-33: Sale of products containing or treated with ether prohibited--Exception--Construction.

No person may sell, offer for sale, or store petroleum products containing or treated with methyl tertiary butyl ether. The provisions of this section do not apply if the presence of methyl tertiary butyl ether in a petroleum product is caused solely by incidental commingling of methyl tertiary butyl ether with the petroleum product during storage or transfer of the petroleum product and the concentration of methyl tertiary butyl ether in the petroleum product does not exceed one-half of one percent by volume. In no event may the provisions of this section be construed to permit the knowing or willful addition of methyl tertiary butyl ether to any petroleum product.