The Romaine Creek portion of the Minker/Stout/Romaine Creek site is located in Jefferson County, Missouri, approximately 20 miles southwest of St. Louis. Romaine Creek starts at the Minker area and flows 4.6 miles to its confluence with Saline Creek. Romaine Creek is located in a rural residential area, and is not used for municipal, industrial or domestic purposes. In the late 1960s and early 1970s, a southwest Missouri chemical plant producing 2,4,5-T and hexachlorophene contracted a waste oil reclaimer to remove process residues. The residues, contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were mixed with waste oils and sprayed as a dust suppressant on a nearby horse arena. In March of 1973, the owner of the horse arena had the contaminated soils removed to various portions of the Minker/Stout/Romaine Creek site. Approximately 120 cu yds of the soil was used as fill in a ravine on the Minker property, and since 1973, much has eroded into Romaine Creek. In 1982, contaminated soils above 1 ug/kg TCDD were excavated from the Minker portion of the site. The primary contaminant of concern is dioxin.