The Kerr-McGee Chemical Corporation (now known as Tronox, Inc.) operated a wood-preserving plant in Columbus, Mississippi, from 1928 to 2003. The plant covers about 90 acres and is surrounded by homes and industrial properties. The company manufactured pressure-treated railroad products such as wooden cross ties, switch ties, and timbers.

The production processes at the site used creosote and creosote coal tar solutions. From the 1950s until the mid-1970s, the facility also used pentachlorophenol (PCP) to treat wood.  The pentachlorophenol process exposed people to pentachlorophenol and to a much lesser degree to dioxin.