Your Local Source for All Things Propane RESIDENTIAL AND COMMERCIAL PROPANE SALES AND SUPPLIES AROUND COLTON, AND SIOUX FALLS, SD Propane is used as a fuel for many residential, commercial and industrial heat applications. If you’re searching for a reliable propane supplier in Colton, South Dakota or the surrounding area, choose Koopman & Sons Gas Co, Inc. For more than 69 years, we’ve offered the best in propane to our customers. We sell propane and propane products. We also offer maintenance and service on these products. Trust a family-owned business that has been around for three generations. For all your propane needs, come to Koopman & Sons Gas Co, Inc. We’re available at 605-446-3265.