Beneath this Chicago forest preserve are the remains of the world’s first nuclear reactor, where experiments conducted by the Manhattan Project lead to the creation of the atomic bomb.
Photo by @woollymammothchicago
The friendly weirdos over at Woolly Mammoth Chicago oddities shop shared this photo of a little known corner of curious history. They write:
“Did you know the world’s first nuclear reactor is buried in the woods about 20 miles southwest of downtown Chicago? The land was leased to The Manhattan Project in the 40’s after initial tests at U of C. The nature of what was happening in the woods was kept a secret from the public until long after WW2, and eventually the 2 story reactor was pushed into a giant hole and covered up.”
The reactor, dubbed Chicago Pile-1, was built by University of Chicago’s Metallurgical Laboratory in 1942, and tests were conducted beneath the stands of the original Stagg Field. It was there that the first self-sustaining chain reaction was demonstrated, proving it could be harnessed for the devastating weapon it would help produce.
The reactor was moved in 1943 to a new laboratory hidden on 19 acres of forested area called “Site A.” Reconfigured and renamed Chicago Pile-2, the reactor continued to carry out experiments that would lead to the creation of the atomic bomb used to bring an end to World War II. Another reactor, Chicago Pile-3, was built there in 1944. Both remained in operation until 1954, conducting nuclear research and producing tritium.
When operations were moved to the new Argonne National Laboratory, the reactors at Site A were imploded and buried on location in an area codenamed “Plot M.”
A radiological survey of Plot M conducted in 1978 by the US Department of Energy states:
Interviews were conducted with twelve people who were at the Laboratory during the time Plot M was used for burial, 1943-49. These individuals included laboratory workers who generated waste that was buried in the Plot and health physicists and others who surveyed waste and actually placed material in the trenches.
Most individuals could provide only very qualitative information. The interviews confirmed that irradiated uranium, fission products, many of the actinide elements, and hydrogen-3, all in various forms, e.g., solutions, solids, contaminated laboratory equipment, injected laboratory animal carcasses, etc., were buried. The amounts of each element or nuclide could not be ascertained in this way and remain unknown.
Though the waste had been buried in steel bins and was covered by a large concrete cap, the survey found that the soil and water within Plot M was contaminated with radioactive tritium.
“The only important pathway for exposure to the public from the radionuclides buried in Plot M,” the report states, “is from the tritiated water moving from the Plot to the dolomite aquifer and consumed by individuals using the picnic wells.”
A cleaning effort was made at some point, and Plot M was deemed safe to the public in 1998 when the fence barricading the area was removed. Today, the site of the Manhattan Project laboratory is known as the Red Gate Woods forest preserve. Various markers, including a sign with photos of Albert Einstein and atomic bomb architect Enrico Fermi visiting the laboratory, tell the story of the site’s significance.
The marker in the photo above sits at the center point of the Plot M burial site.