7295 Highway 94 South
St. Charles County, Missouri
636-300-2600
In 1940 when it was apparent the United States would eventually be drawn into World War II the Army purchased 17,232 acres of largely rural land near Weldon Spring. Displacing towns of Hamburg, Howell, and Toonerville and 576 citizens of the area the army built the Weldon Spring Ordnance Works. The Atlas Powder Company operated the plant and production began in 1941. At its peak more than 5,000 people were employed in over 1,000 buildings produced over 700 million pounds of TNT by the end of the war. After the war the Army sold most of the land to the Missouri Department of Conservation and the University of Missouri. Those acreages are now the Busch Memorial Conservation Area and the Weldon Spring Conservation Area.
The Army kept 200 acres and on this property the U.S. Atomic Energy Commission built a uranium ore processing plant in 1958. The Weldon Spring Uranium Feed Mill Plant processed raw uranium ore into “yellow cake,” or concentrated ore that was shipped to other sites. The toxic materials produced by the plant were stored in open-air lagoons along with TNT and wastes and uranium and radioactive materials were disposed of in a quarry. In 1967 the Army took over the plant to produce dangerous herbicides. The processing plant operated until 1968 after which the site was abandoned but still contained contaminated equipment and hazardous chemicals.
In the 1985 the U.S. Department of Energy took over the site to clean it up. In 2001 workers completed the burial of 1.5 million cubic yards of waste in a covered mound that fills 45 acres and reaches 75 feet in the air. A viewing platform on top of the disposal cell is the highest accessible point in St. Charles County and has four plaques that provide information about the local area, the history of the site, and the construction of the disposal cell.
In 2002 the interpretive center was opened to the public. This 9,000-square-foot interpretive center is housed in a building that was once used to check workers for radioactivity. Exhibits explain the site's history, including of the towns of Toonerville, Howell, and Hamburg, a timeline of significant events of the site, the legacy of the TNT and uranium plants, the efforts of the community to clean up the site, and how the disposal cell was constructed.
The area features the Hamburg Trail, a ten-mile bike trail that connects the site to the August Busch Memorial Conservation Area, the Weldon Spring Conservation Area, and KATY Trail State Park. The Howell Prairie consists of 150 acres surrounding the disposal cell that has been seeded with over 100 species of native prairie grasses and forbs that mirror the pre-European settlement landscape.
Visiting the Weldon Spring Site & Interpretive Center
Visiting Hours:
April 1 - October 31:
Monday - Friday: 9 am - 5 pm
Saturday: 10 am - 4 pm (April 1 - October 31)
or 10 am - 2 pm (November 1 - March 31)
Sunday: 12 pm - 4 pm
Closed on Holidays
There is no charge to visit the Weldon Spring Site & Interpretive Center
