SDCL § 38-19-24: Intimate and uniform mixture required in custom mixing.

A licensee shall at all times produce an intimate and uniform mixture of fertilizer materials. When two or more fertilizer materials are delivered in the same load, they shall be intimately and uniformly mixed unless they are in separate compartments. To provide for intimate and uniform mixture of fertilizer materials, the secretary, pursuant to the provisions of chapter 1-26, may promulgate rules to establish good manufacturing practices.