Coldwater Creek contamination

From 1942 to 1957, Mallinckrodt used this 45-acre site along the north riverfront to extract uranium and radium from ore for the development of the country's first nuclear weapons.

Residual radioactive byproducts from downtown were transported to a site just north of the airport and stored there from 1946 to 1966, when Continental Mining and Milling purchased some and trucked it about one mile away, to the 9200 block of Latty Avenue. It was stored there before being shipped to Colorado. Eventually the structures here were razed and the scrap buried.

Contamination from these properties got into the surrounding areas, including nearby baseball fields and Coldwater Creek, where it moved downstream toward the Missouri River. Beginning in 1979, the federal government began excavating and remediating the St. Louis Airport Site and the Latty Avenue Site and some of the nearby properties.

Since 2012, the Army Corps of Engineers has tested soil within the creek's 10-year floodplain for residual radioactive contamination. In 2021, the work reached the Old Halls Ferry Road area, about 10 miles downstream of the airport. The Corps has cleaned up a few areas along the creek and plans to start remediating other hot spots within two years. The completion goal is 2038.