US Army Corps of Engineers
St. Louis District Website

Welcome to What is FUSRAP? — FUSRAP Cleanup Overview

For a time line, go to Contamination and Chronology.

St. Louis Downtown Site (SLDS) 

In 1942 during World War II, the Manhattan Engineer District (MED) achieved the first self-sustained nuclear chain reaction at Stagg Field at the University of Chicago, using uranium oxide produced by the Destrehan Street Refinery and Metal Plant (later Mallinckrodt Chemical Works) in downtown St. Louis.

Following the success of the Stagg Field experiment, MED contracted with Mallinckrodt to process uranium. Under this contract, uranium and radium were extracted from ore and used to make the first atomic bombs. Years later, this facility became known as the St. Louis Downtown Site (SLDS).

From 1942 to 1957, under contracts with the Manhattan Engineer District (MED) and the Atomic Energy Commission (AEC), the site was used for processing various forms of uranium compounds, for machining and for recovery of uranium metal.

In 1946, the manufacture of uranium dioxide from pitchblende (the essential ore of uranium) began at a newly constructed plant.

At the time of the MED/AEC operations, the plants were owned by Mallinckrodt and/or leased by AEC. Certain buildings in those plants were also constructed for and owned by AEC. From 1942 through 1945, uranium processing was conducted at Plants 1, 2 and 4. In 1945, operations at Plant 2 were terminated. Some uranium metallurgical research continued at Plant 4 through 1956. From 1945 to 1957, uranium concentrate or ore was processed in buildings at Destrehan Street (Plants 6, 6E and 7). All uranium-extraction operations at the Destrehan Street location ceased in 1957. 

St. Louis Airport Site (SLAPS) 

In 1946, the Manhattan Engineer District (MED) acquired the 21.7-acre tract of land now known as the St. Louis Airport Site (SLAPS) to store residues from uranium processing at the Mallinckrodt facility in St. Louis. 

The uranium processing, conducted under a contract with MED/AEC (Atomic Energy Commission), continued through 1957; the resulting radioactive residues accumulated at SLAPS. These materials included pitchblende raffinate residues, radium-bearing residues, barium-sulfate cake, Colorado raffinate residues, and contaminated scrap. Some of the residues were stored in bulk on open ground. Others were stored in drums that were stacked across the site. Some contaminated materials and scrap iron were buried at the western end and in other parts of the property. To limit direct radiation exposure of the public, the property was fenced to prevent casual entry.

In 1966 and 1967, most of the stored residues were sold to a private entity for recycling and were removed from SLAPS. On-site structures were razed, buried on the property and covered with 1 to 3 feet of clean fill material. Although these activities reduced the surface dose rate to levels acceptable at the time, buried deposits of uranium-238, radium-226 and thorium-230 remained on the property. 

Madison Site 

During the late 1950s and early 1960s, Dow Chemical Company, a division of Dow Metal Products, in Madison, Illinois, operated as a uranium-extrusion and rod-straightening facility, working with Mallinckrodt Chemical to support Atomic Energy Commission (AEC) needs.

Latty Avenue Properties 

In early 1966, ore residues and uranium- and radium-bearing process wastes that had been stored at SLAPS were purchased by the Continental Mining and Milling Company and moved to a storage site on Latty Avenue. 

These wastes were generated at the Mallinckrodt plant in St. Louis from 1942 through the late 1950s under contracts with the Manhattan Engineer District and the Atomic Energy Commission (MED/AEC). Residues on the property at that time included 74,000 tons of Belgian Congo pitchblende raffinate containing approximately 13 tons of uranium; 32,500 tons of Colorado raffinate containing roughly 48 tons of uranium; and 8,700 tons of leached barium sulfate containing about 7 tons of uranium. 

The Commercial Discount Corporation of Chicago, Illinois, purchased the residues in January 1967. Much of the material was then dried and shipped to Cañon (pronounced "Canyon") City, Colorado. The material remaining at the Latty Avenue storage site was sold to Cotter Corporation in December 1969. From August through November 1970, Cotter Corporation dried some of the remaining residues and shipped them to its mill in Cañon City. In December 1970, an estimated 10,000 tons of Colorado raffinate and 8,700 tons of leached barium sulfate remained at the Latty Avenue properties. 

St. Louis Airport Site Vicinity Properties (SLAPS VPs) 

Low-level radioactive contamination at St. Louis Airport Site vicinity properties (SLAPS VPs) is linked to both SLAPS and the Latty Avenue Properties. 

In 1966, Continental Mining and Milling Company of Chicago purchased uranium-bearing residues from the Manhattan Engineer District (MED) and removed them from SLAPS. 

The company placed the residues in storage at Latty Avenue under an Atomic Energy Commission (AEC) license. Over time, residues migrated from other sites or were deposited as the residues were hauled along transportation routes, contaminating the soils and sediments of the vicinity properties. 

FUSRAP: Overview Slide Show

Photo of Coldwater Creek.
Photo of remedial action on Eva Avenue in Hazelwood, Missouri, during utility support for roadwork.
FUSRAP Open House postponement postcard
During the first shipping campaign at the Iowa Army Ammunition Plant, approximately 1,900 cubic yards of depleted uranium contaminated soil were loaded onto railcars and shipped out of the installation.
Approximately 15 miles from downtown St. Louis, the St. Louis Airport Project Site is immediately north of St. Louis Lambert International Airport and is bounded by the Norfolk and Western Railroad and Banshee Road on the south, Coldwater Creek on the west, and McDonnell Boulevard and adjacent recreational fields on the north and east.
Workers conduct remedial activities on one of the St. Louis Airport Site Vicinity Properties.
The approach to Coldwater Creek is to first eliminate the sources of contamination. The U.S. Army Corps of Engineers is currently remediating properties adjacent to CWC from upstream to downstream.
The St. Louis Downtown Site (SLDS) is located in an industrial area on the eastern edge of St. Louis, just 300 feet west of the Mississippi River. About 11 miles southeast of the St. Louis Lambert International Airport, SLDS is comprised of approximately 210 acres of land, which includes Mallinckrodt Inc. (formerly Mallinckrodt Chemical Works) and 38 surrounding vicinity properties (VPs).
The U.S. Army Corps of Engineers' Formerly Utilized Sites Remedial Action Program (FUSRAP) is currently remediating properties adjacent to Coldwater Creek from upstream to downstream. In 1998, USACE removed contamination from Coldwater Creek to support the City of Florissant’s upgrade of the St. Denis Bridge over the creek. In 2005, contamination in CWC was removed as part of the cleanup at SLAPS.

What is FUSRAP?

The Formerly Utilized Sites Remedial Action Program (FUSRAP) is an environmental remediation program. It addresses radiological contamination generated by activities of the Manhattan Engineer District and the Atomic Energy Commission (MED/AEC) during development of the atomic weapons in the 1940s and 1950s.  

After MED/AEC activities ceased, uranium-processing sites were decontaminated according to the standards of the day. However, today's cleanup standards are much more stringent, requiring additional cleanup. 


From 1942 to 1957, the Mallinckrodt Chemical Plant extracted uranium and radium from ore at the St. Louis Downtown Site (SLDS) in St. Louis, Missouri. During this time and until 1967, radioactive process byproducts were stored at an area adjacent to St. Louis Lambert International Airport (once known as Lambert-St. Louis Airport). This area is now referred to as the St. Louis Airport Site (SLAPS). 

In 1966, certain SLAPS wastes were purchased, moved and stored at Latty Avenue. Part of this property later became known as the Hazelwood Interim Storage Site (HISS). During this move, improper handling and transportation of the contamination caused the spread of materials along haul routes and to adjacent vicinity properties forming the St. Louis Airport Site Vicinity Properties (SLAPS VPs).

During the late 1950s and early 1960s, Dow Chemical Company in Madison, Illinois, operated as a uranium-extrusion and rod-straightening facility leaving contamination in dust located on roof beams at the Madison Site.

The U.S. Army Corps of Engineers, St. Louis District, is conducting a radiological cleanup program for these five St. Louis Sites (SLDS, SLAPS, SLAPS VPs, Latty Avenue Properties and Madison). The sites contain soils contaminated with uranium, thorium and radium, as a result of federal defense activities performed under contracts with the Manhattan Engineer District and the Atomic Energy Commission (MED/AEC) in the 1940s and 1950s. (See Contamination and Chronology for more information.)

The 1998 Energy and Water Development Appropriations Bill, through which Congress transferred management of the Formerly Utilized Sites Remedial Action Program (FUSRAP) to the U.S. Army Corps of Engineers (USACE), was signed into law Oct. 13, 1997. Prior to the signing of this bill, FUSRAP was managed by the U.S. Department of Energy.

How hazardous are FUSRAP sites?

Even though FUSRAP sites contain levels of radioactivity above current guidelines, none pose an immediate health risk to the public or environment given their current land uses. The contaminated materials have very low concentrations and people aren’t exposed to them for long periods of time.

Although these materials don’t pose an immediate hazard, they will remain radioactive for thousands of years, and health risks could increase if the use of the land were to change. Under FUSRAP, each site is cleaned to levels acceptable for the projected future use for the land, such as residential development, industrial operations or recreational use.

What are FUSRAP's objectives?

The objectives of FUSRAP are to:
• Protect human health and the environment;
• Execute the approved alternative for cleaning up the radioactive contamination above health-based cleanup guidelines; and
• Minimize adverse effects on area business operations.

How does FUSRAP work?

FUSRAP sites undergo several steps that lead to cleanup. Information about the site is collected and reviewed. A Remedial Investigation/Feasibility Study (RI/FS) is conducted to develop cleanup alternatives.

The Remedial Investigation identifies the type and location of the contamination. The Feasibility Study develops and evaluates cleanup alternatives. The public is informed about the development of the RI/FS cleanup alternatives through public meetings and the media. Public participation is especially encouraged during the selection of the final remediation, or cleanup, method.

When a cleanup alternative is chosen, a Proposed Plan (PP) is written to explain why it was chosen. Members of the public are asked to comment on the cleanup options, including the selected remedy. After public comments have been considered, a final decision is made and documented in a Record of Decision (ROD). The Remedial Design follows the ROD and includes technical drawings and specifications that show how the cleanup will be conducted.

Cleanup, or Remedial Action, begins after the Remedial Design is complete. This phase involves site preparation and construction activities. When these remediation activities are completed, verification surveys are conducted to ensure that cleanup objectives for the site have been met and are documented in a Post-Remedial Action Report (PRAR).

More about FUSRAP

Protect human health and the environment.

Execute the approved alternative for cleaning up the radioactive contamination above health-based cleanup guidelines.

Minimize adverse impacts on residents and area business operations.

Return sites for appropriate beneficial use.

U.S. Army Corps of Engineers
St. Louis District 
FUSRAP Area Office
114 James S. McDonnell Blvd.
Hazelwood, MO 63042

314-260-3905 NOTE: Due to COVID-19, phone messages are checked weekly.