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FUSRAP: Contamination and Chronology Slide Show

Photo of Coldwater Creek.
Photo of remedial action on Eva Avenue in Hazelwood, Missouri, during utility support for roadwork.
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.
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.

Contamination and Chronology



In October, Adolf Hitler annexes the Sudetenland, the historically German name for an area populated by Sudeten Germans on the northern, western and southern rim of Czechoslovakia, as a pretext for eventually taking over all of Czechoslovakia, a rich source of high-quality uranium ore.


German forces begin to occupy the rest of Czechoslovakia March 15.

Adolf Hitler creates the Protectorate of Bohemia and Moravia in Czechoslovakia March 16.

The Uranprojekt (Nazi Nuclear Program) is established in April.

Scientist Albert Einstein writes a letter to American President Franklin Delano Roosevelt Aug. 2, to elucidate the importance of nuclear chain reactions and to warn the president that Germany had stopped the sale of uranium from what had been Czech mines. 

World War II begins when Adolf Hitler invades Poland Sept. 1, 1939.



Germany, Japan and Italy sign the Tripartite Pact, also known as the Axis alliance, Sept. 27. 


Japan declares war on the United States, following its surprise air attack on Pearl Harbor, Oahu, Hawaii, Dec. 7.

In President Franklin Delano Roosevelt's speech to Congress Dec. 8, broadcast to the nation, he immortalizes Dec. 7, 1941, as "a date which will live in infamy," and the United States declares war on Japan. Read Roosevelt's speech. 

Germany and Italy declare war on the United States Dec. 11. The United States responds with a Declaration of War on the two countries the same day. 


The Manhattan Engineer District (MED) achieves the first self-sustained nuclear chain reaction, conducted by Italian-born American scientist Enrico Fermi et al., Dec. 2 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 contracts with Mallinckrodt to process uranium. Under this contract, uranium and radium are extracted from ore and used to make the first atomic bombs. Years later, this facility will become known as the St. Louis Downtown Site (SLDS).


The first atomic bomb is tested at White Sands Test Range in Alamogordo, New Mexico, July 16.

On Aug. 6 and 9, atomic bombs are detonated at Hiroshima and Nagasaki. 

Japan announces its surrender Aug. 15 (Victory Over Japan, or V-J, Day) and signs the instrument of surrender aboard USS Missouri in Tokyo Bay Sept. 2. World War II officially ends.


MED acquires land from the City of St. Louis and obtains consent to store process byproducts containing radioactive residuals from the Mallinckrodt plant. Most of the wastes and residues are stored on open ground. Some contaminated materials and scrap are buried at the western end and other parts of the site. Later, this land becomes known as the St. Louis Airport Site (SLAPS).

Congress passes the Atomic Energy Act in September, which creates the five-member Atomic Energy Commission (AEC) to manage the atomic energy program. On Dec. 31, the Manhattan Engineer District is inactivated. The newly created AEC assumes the Manhattan Engineer District's responsibilities.


With AEC financing, Mallinckrodt begins to decontaminate Plants 1 and 2.



The AEC releases Mallinckrodt Plants 1 and 2 for use without radiological restrictions.


AEC operations downtown close. From 1942 to 1957, the plant had processed more than 50,000 tons of uranium product. Contaminated scrap metal and miscellaneous radioactive wastes are transported to SLAPS and buried on the western edge of the property.

1960s 1960

AEC offers uranium-processing residues and wastes at SLAPS for sale.


In a waste inventory and radiological survey conducted at SLAPS, the AEC finds approximately 121,000 tons of uranium refinery residues and contaminated material.


In February, Continental Mining and Milling Co. purchases wastes stored at SLAPS and begins moving them to 9200 Latty Ave. in Berkeley, Missouri. Improper storage, handling and transportation of materials causes the spread of these materials along haul routes to vicinity properties (SLAPS VPs). The Latty Avenue property, where the wastes from SLAPS were stored, will later become known as the Hazelwood Interim Storage Site (HISS).

After removal of most residuals to HISS, structures on SLAPS are demolished and buried on the property. Sixty truckloads of scrap metal and a contaminated vehicle are buried on the property. A total of 1 to 3 feet of clean fill material is spread over SLAPS to achieve acceptable levels of surface radioactivity.


Commercial Discount Corporation purchases the residues stored on HISS and, after drying, ships much of the material to Cañon (pronounced "Canyon") City, Colorado.


Cotter Corporation purchases the remaining residues at HISS, dries the material and ships additional material to Cañon City during 1970.

1970s 1970

The U.S. Environmental Protection Agency is formed.


The AEC conveys the SLAPS property by quitclaim deed to the St. Louis Airport Authority.

Cotter concludes its shipping operation at HISS. The remaining contaminated material (barium sulfate) is mixed with approximately five times as much topsoil "to disperse and dilute the uranium-bearing residues" and is disposed of in a St. Louis County landfill.


AEC establishes the Formerly Utilized Sites Remedial Action Program (FUSRAP) for the cleanup of sites not owned by the Department of Energy but contaminated from past activities involving radioactive materials. The SLDS, SLAPS, SLAPS VPs and HISS sites are eventually placed in FUSRAP.

In a reorganization of the state government, the Missouri Department of Natural Resources (MDNR) is formed.


The Atomic Energy Commission is replaced by two new federal agencies. The Nuclear Regulatory Commission (NRC) is charged with regulating the civilian uses of atomic energy (mainly nuclear power plants); the Energy Research and Development Administration (ERDA) has duties that include the control of the nuclear-weapons complex.


The Nuclear Regulatory Commission (NRC) conducts a radiological survey of HISS and determined the residual uranium concentrations, thorium concentrations and gamma exposure levels exceeded guidelines for release of the property without radiological restrictions.

From 1976 until 1978, radiological investigations of SLAPS and Latty Avenue are performed. Contamination is found at both sites, along with elevated radionuclide concentrations on site and north of the site in ditches along McDonnell Boulevard. The ditches are designated for remedial action under FUSRAP.


ERDA is transferred to the newly created the U.S. Department of Energy (DOE).

The buildings and grounds at 9200 Latty Ave. are purchased by the current owner and leased to a manufacturing facility. A follow-up radiological characterization of HISS is conducted prior to occupancy. This survey disclosed uranium, thorium and radium in and around the building and subsurface.


During a cleanup performed by the new owner under NRC guidance,13,000 cubic yards of material are excavated from the western half of the 9200 Latty Ave. and stockpiled on the eastern to form the main storage pile at HISS.



SLAPS is designated for remedial action under FUSRAP.

A radiological characterization of the pile and portions of the northern and eastern vicinity properties for HISS is performed. Levels of contamination similar to those on the pile are found in both areas.


DOE performs a radiological characterization of the ditches to the north and south of SLAPS and of portions of Coldwater Creek. The characterization sampling effort indicates radioactive levels exceed DOE guidelines then in effect.


As a follow-up to the 1981 HISS/Latty Avenue survey, a detailed radiological survey of the northern and southern shoulders of Latty Avenue is conducted. Results indicate that contamination in excess of federal guidelines is present along the road beyond Hazelwood Avenue. Properties adjacent to HISS are also found to be contaminated in excess of guidelines.

The Energy and Water Development Appropriations Act directs DOE to conduct a decontamination research and development project at four sites throughout the nation, one of which is HISS. Results of the survey demonstrate that the property exceeds guidelines for residual radioactive material given in DOE Order 5400.5. Subsequently, Congress adds HISS to FUSRAP in order to expedite decontamination.

DOE is directed by Congress to reacquire SLAPS (Public Law 98-360) and use it as a permanent disposal site for waste already on the property, contaminated soil in the surrounding ditches and the waste from HISS. The City of St. Louis refuses to transfer the property to DOE.

DOE begins clearing the property at 9200 Latty Ave. and selected adjacent properties, constructing a vehicle-decontamination facility, installing a perimeter fence at HISS, excavating and backfilling the edges and shoulders of Latty Avenue, and consolidating and covering the contaminated soil storage pile. These activities result in adding 14,000 cubic yards of contaminated soils to the 13,000 cubic yards of material already in the storage pile.


Erosion on the western side of SLAPS along Coldwater Creek necessitates emergency maintenance. Sloughing and seepage are causing erosion of contaminated fill and loess (soil) materials into the creek. The problem is temporarily corrected by installing a gabion wall (constructed of rock-filled wire baskets) along the western edge of the property.

DOE performs a radiological survey of the roads thought to have been used to transport contaminated materials to and from SLAPS and HISS. Gamma scans of roadsides detect exposure rates in excess of background due to elevated concentrations of radium-226 and uranium-238 in the soil. Thorium-230, an alpha emitter, is determined to be a primary radioactive contaminant in soil on the basis of its activity. Parts of Hazelwood Avenue, Pershall Road and McDonnell Boulevard are designated by DOE for remedial action.


DOE provides radiological support to the cities of Berkeley and Hazelwood for drainage/road-improvement project along Latty Avenue. An additional 4,600 cubic yards of material is placed in a supplementary storage pile at HISS.

Boreholes are drilled at SLAPS and SLAPS VPs to define the nature and extent of the subsurface contamination and geological conditions. A radiological and limited chemical characterization of SLAPS determines that radioactive impacts extend as deep as 5.5 meters (18 feet) below grade. Further surveys identify additional areas of contamination along the shoulders of McDonnell Boulevard, Hazelwood Avenue and Pershall Road.


Further investigation of the original transportation routes is conducted. A complete radiological characterization, which consists of sampling and analysis to determine the nature and extent of contamination, is conducted at HISS, along Coldwater Creek and on about 70 haul-road properties. Contamination on the haul-road properties is found on road shoulders and adjacent properties. Contamination is shallow (less than 1 foot deep), and concentrations are low. Although characterization is essentially complete, some additional investigation in the creek and along haul roads is still required. Chemical characterization of SLAPS and HISS is completed.

The U.S. Army Corps of Engineers requests that DOE survey an additional portion of Coldwater Creek as part of the Coldwater Creek Local Flood Protection Project.


Radiological characterization, which consists of sampling and analyses to determine the nature and extent of contamination, is performed at SLDS.


SLAPS and HISS are added to the Environmental Protection Agency's National Priorities List (NPL). This list requires the cleanup to proceed under the guidelines of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) as amended by the Superfund Amendments and Reauthorization Act (SARA).

Characterization studies of the section of Coldwater Creek from Banshee Road to Old Halls Ferry Road indicate low-level radioactive contamination is present in the Coldwater Creek channel.

A survey of the Dow Chemical Company Buildings in Madison, Illinois, indicates low-level radioactive contamination is present in dust located on overhead surfaces in Building 6. About 2 cubic yards of contaminated uranium/thorium dust from MED/AEC operations is identified on roof beams at the facility.

1990s 1990

The Environmental Protection Agency (EPA) and DOE sign a Federal Facilities Agreement, which establishes an environmental review process and establishes a schedule for the remediation of SLAPS, SLDS and HISS. The process requires DOE to evaluate alternatives for waste management, one of which is storage at SLAPS.

The City of St. Louis offers to transfer the SLAPS property back to DOE under the condition that a permanent disposal cell for radioactive wastes won't be constructed on the site. DOE declines acceptance of the SLAPS property from the city until the environmental review process is conducted.

Radiological characterization activities are conducted on the six properties adjacent to Mallinckrodt to determine whether contamination extends beyond the Mallinckrodt property boundaries.


An Engineering Evaluation/Cost Analysis (EE/CA), which outlines the scope of interim removal actions at SLDS, is prepared and released for review and comment to the public. Once DOE prepares a Responsiveness Summary to address the comments received on the SLDS EE/CA, limited removal action activities are undertaken at SLDS.


The Madison Site is added to the FUSRAP list of sites slated for cleanup. The FUSRAP site is located within a limited area of an active facility.


The St. Louis Site Remediation Task Force is established. Two citizens committees are established for the purpose of working closely with FUSRAP representatives and serving as a "voice of the people." These organizations are the St. Louis Radioactive and Hazardous Waste Oversight Committee and the City of St. Louis Mayor's Advisory Task Force on Radioactive Waste. Later the same year, the members of these two groups join together with other community stakeholders to form the St. Louis Sites Remediation Task Force.


Contaminated soils are removed from seven residential vicinity properties, beginning the North County sites cleanup.

A total of 15,043 cubic yards of contaminated soil is excavated from the Mallinckrodt Plant 10 area (SLDS) and shipped to a licensed, out-of-state disposal facility.


The owner of 9150 Latty Ave., located to the east of HISS, expands the facility and stockpiles about 8,000 cubic yards of contaminated soil on the southwestern corner of the property. This stockpile becomes known as the Eastern Pile.

At SLDS, 750 cubic yards of contaminated soil is excavated from the City Property, Riverfront Trail area, and shipped to a licensed, out-of-state disposal facility.

The 50-series buildings on the Mallinckrodt property are decontaminated and demolished. Contaminated materials are transported by covered gondola cars for disposal in a licensed, out-of-state facility. Brick and cinder blocks are crushed and piled on site to await disposition.

The St. Louis Site Remediation Task Force releases its report containing local stakeholders' conclusions and recommendations for remediating the St. Louis FUSRAP sites.


The St. Louis Oversight Committee is formed from a subset of the St. Louis Remediation Task Force to act as a citizens advisory group in the decision-making process for the St. Louis FUSRAP Sites.

Plant 6 and 7 Buildings are decontaminated and demolished. Contaminated materials are transported by covered gondola cars for disposal in a licensed out-of-state disposal facility. Brick and cinder blocks are crushed and piled onsite to await disposition.

On Oct. 13, the Fiscal Year 1998 Energy and Water Appropriations Act transfers the FUSRAP project to the U.S. Army Corps of Engineers. The St. Louis District of the Corps of Engineers is chosen to carry out remediation on the St. Louis sites. Cleanup activities continue to follow CERCLA guidelines and incorporate National Contingency Plan, or NCP, values.

After public review and comment on an EE/CA released earlier in the year under DOE, the U.S. Army Corps of Engineers completes the removal of approximately 5,100 cubic yards of contaminated material from the west end of SLAPS adjacent to the gabion wall. The area is backfilled with clean soils in December 1997.

Radiological surveys in the vicinity of two bridges over Coldwater Creek in Florissant are performed to support upcoming bridge replacements.


In March, the U.S. Army Corps of Engineers issues two Engineering Evaluation/Cost Analysis (EE/CA) documents (one for SLAPS and one for HISS), which identify potential cleanup measures to be used until a comprehensive cleanup can be achieved. The SLAPS EE/CA includes the Ballfields property as part of the SLAPS/SLAPS VP cleanup and evaluates several possible interim cleanup measures. The HISS EE/CA includes VP No. 2 and soils on three Latty Avenue properties as part of the HISS cleanup and evaluates several possible interim cleanup measures. Both of these documents are presented for public comment and regulatory review at a public meeting in March.

In April, the U.S. Army Corps of Engineers issues a Proposed Plan to the public for review and comment detailing the preferred alternative for final cleanup of SLDS. In August, the EPA approves the final cleanup remedy outlined in the SLDS Record of Decision (ROD).

Building K is decontaminated by the government and demolished by Mallinckrodt. Contaminated materials are transported by covered gondola cars for disposal in a licensed, out-of-state disposal facility.

A detailed characterization, including sampling and analysis, is performed at the Madison Site. The survey includes scanning for gamma radiation on accessible floor and wall surfaces throughout the building and on overhead beams, collection and analysis of indoor dust and debris, and determination of radioactivity levels on overhead beam surfaces.

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

NOTE: Due to 2019 novel-coronavirus disease, or COVID-19, the FUSRAP Area Office in Hazelwood, Missouri, will be closed to visitors for the foreseeable future. 


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