Site A
Encyclopedia
The Site A/Plot M Disposal Site is located within Red Gate Woods
Red Gate Woods
Red Gate Woods is a forest preserve within the Palos Division of the Forest Preserve District of Cook County, Illinois. Located within the preserve is the original site of Argonne National Laboratory and the Site A/Plot M Disposal Site, which contains the buried remains of Chicago Pile-1, the...

 and situated on the former grounds of Argonne National Laboratory
Argonne National Laboratory
Argonne National Laboratory is the first science and engineering research national laboratory in the United States, receiving this designation on July 1, 1946. It is the largest national laboratory by size and scope in the Midwest...

 and its predecessor, the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...

 Metallurgical Laboratory
Metallurgical Laboratory
The Metallurgical Laboratory or "Met Lab" at the University of Chicago was part of the World War II–era Manhattan Project, created by the United States to develop an atomic bomb...

 in Cook County, Illinois
Cook County, Illinois
Cook County is a county in the U.S. state of Illinois, with its county seat in Chicago. It is the second most populous county in the United States after Los Angeles County. The county has 5,194,675 residents, which is 40.5 percent of all Illinois residents. Cook County's population is larger than...

 and is now part of the Palos Forest Preserve. The site contains buried radioactive waste
Radioactive waste
Radioactive wastes are wastes that contain radioactive material. Radioactive wastes are usually by-products of nuclear power generation and other applications of nuclear fission or nuclear technology, such as research and medicine...

 from contaminated building debris, and the Chicago Pile-1
Chicago Pile-1
Chicago Pile-1 was the world's first man-made nuclear reactor. CP-1 was built on a rackets court, under the abandoned west stands of the original Alonzo Stagg Field stadium, at the University of Chicago. The first self-sustaining nuclear chain reaction was initiated in CP-1 on December 2, 1942...

 (CP-1/CP-2), and Chicago Pile-3 (CP-3) nuclear reactors.

Site history

Shortly after the December 1942 demonstration of the first self-sustaining chain reaction at the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...

, the research group led by Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...

 needed to move to a larger, more remote laboratory campus. The U.S. Army Corps of Engineers leased 1025 acres (4.1 km²) from the Cook County Forest Preserve District, and placed the wartime reactor laboratory on 19 acres (76,890.3 m²) within the forest. The first reactor, CP-1, was disassembled and moved to Site A in March 1943, renamed as Chicago Pile 2. In May 1944 the laboratory first operated a second, heavy water
Heavy water
Heavy water is water highly enriched in the hydrogen isotope deuterium; e.g., heavy water used in CANDU reactors is 99.75% enriched by hydrogen atom-fraction...

-moderated reactor, CP-3 on the site. Argonne National Laboratory
Argonne National Laboratory
Argonne National Laboratory is the first science and engineering research national laboratory in the United States, receiving this designation on July 1, 1946. It is the largest national laboratory by size and scope in the Midwest...

 obtained an even larger, permanent site in Du Page County in 1947 and began moving its operations out of Site A to the new site. The two reactors operated until 1954, conducting reactor research and production of tritium
Tritium
Tritium is a radioactive isotope of hydrogen. The nucleus of tritium contains one proton and two neutrons, whereas the nucleus of protium contains one proton and no neutrons...

. Decontamination and demolition of the buildings began in 1955. The reactors were defueled and the concrete shell for CP-3 was imploded and buried. In 1956 the property was returned to the forest preserve. Two granite monuments mark Site A and Plot M.
The Plot M marker reads:
CAUTION-DO NOT DIG
Buried in this area is radioactive
material from nuclear research
conducted here 1945-1949. Burial
area is marked by six corner markers
100ft from this center point.
There is no danger to visitors.
U.S. Department of Energy 1978

The markers have since been vandalized, with vandals chiseling off the word "NO."

Plot M was a dump for low-level radioactive waste generated at the site between 1943 and 1949. Initially buried in trenches, later in steel bins, the waste included tritium
Tritium
Tritium is a radioactive isotope of hydrogen. The nucleus of tritium contains one proton and two neutrons, whereas the nucleus of protium contains one proton and no neutrons...

, uranium
Uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...

, and fission products in various forms including contaminated equipment, animal carcases, and solids. In 1949 the burial of waste at the site was halted, and the dump was covered with grass until 1956, when a concrete cover was installed to protect the landfill from rainwater.

Surveillance of the site since the demolition in the 1950s has found small amounts of soil contamination with uranium and fission products, and some wells in Red Gate Woods had tritium concentrations as high as 13 nCi/l in the late 1970s.

In April 1998 the fence separating Site A from the rest of Red Gate Woods was taken down after a DOE determination that the risk to the public of enjoying the forest preserve is minimal.

Location

Site A is located near 41.702364°N 87.913306°W. Plot M is located near 41.707268°N 87.910516°W.

During the Glenwood stage of Lake Chicago
Lake Chicago
This article is about the prehistoric lake, For other geographic features with this name, see ChicagoLake Chicago was a prehistoric proglacial lake that is the ancestor of what is now known as Lake Michigan, one of North America's five Great Lakes....

, this was part of Mount Forest Island, a triangular island 6 miles (9.7 km) long and 4 miles (6.4 km) wide, rising 80 to 120 feet (36.6 m) above the surrounding waters.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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