35°55′56″N 84°23′42″W / 35.93222°N 84.39500°W / 35.93222; -84.39500
166-599: K-25 was the codename given by the Manhattan Project to the program to produce enriched uranium for atomic bombs using the gaseous diffusion method. Originally the codename for the product, over time it came to refer to the project, the production facility located at the Clinton Engineer Works in Oak Ridge, Tennessee , the main gaseous diffusion building, and ultimately the site. When it
332-587: A German atomic bomb project would develop atomic weapons first, especially among scientists who were refugees from Nazi Germany and other fascist countries, were expressed in the Einstein-Szilard letter to the President of the United States , Franklin D. Roosevelt . This prompted Roosevelt to initiate preliminary research in late 1939. Niels Bohr and John Archibald Wheeler applied
498-494: A German atomic bomb project would develop one first, especially among scientists who were refugees from Nazi Germany and other fascist countries. In August 1939, Hungarian-born physicists Leo Szilard and Eugene Wigner drafted the Einstein–Szilard letter , which warned of the potential development of "extremely powerful bombs of a new type". It urged the United States to acquire stockpiles of uranium ore and accelerate
664-755: A neutron moderator . The S-1 Committee recommended pursuing all five technologies. This was approved by Bush, Conant, and Brigadier General Wilhelm D. Styer , who had been designated the Army's representative on nuclear matters. Bush and Conant then took the recommendation to the Top Policy Group with a budget proposal for $ 54 million for construction by the United States Army Corps of Engineers , $ 31 million for research and development by OSRD and $ 5 million for contingencies in fiscal year 1943. They sent it on 17 June 1942, to
830-558: A reciprocating pump would suffice, and these were designed by Boorse at the SAM Laboratories, while Ingersoll Rand tackled the centrifugal pumps. In early 1943, Ingersoll Rand pulled out. Keith approached the Clark Compressor Company and Worthington Pump and Machinery , but they turned it down, saying it could not be done. So Keith and Groves met with executives at Allis-Chalmers , who agreed to build
996-444: A segregated lunch room for African Americans. There were three changing houses (K-1008-A, B and C), a dispensary (K-1003), an instrument repair building (K-1024), and a fire station (K-1021). In mid-January 1945, Kellex proposed an extension to K-25 to allow product enrichment of up to 85 percent. Groves initially approved this but later canceled it in favor of a 540-stage side feed unit, which became known as K-27, which could process
1162-506: A 360-foot (110 m) long bridge in December 1943. A 10.7-mile (17.2 km) railroad spur was run from Blair, Tennessee , to the K-25 site. Some 12.9 miles (20.8 km) of sidings were also provided. The first carload of freight traversed the line on 18 September 1943. It was initially intended that the construction workers should live off-site, but the poor condition of the roads and
1328-619: A AAA rating whenever it was required. Nelson initially balked but quickly caved in when Groves threatened to go to the President. Groves promised not to use the AAA rating unless it was necessary. It soon transpired that for the routine requirements of the project the AAA rating was too high but the AA-3 rating was too low. After a long campaign, Groves finally received AA-1 authority on 1 July 1944. According to Groves, "In Washington you became aware of
1494-474: A Chinese copy" of a section of K-25. By 31 December 1946, when the Manhattan Project ended, 110,048,961 man-hours of construction work had been performed at the K-25 site. The total cost, including that of K-27, was $ 479,589,999 (equivalent to $ 6.44 billion in 2023). The water tower (K-1206-F) was a 382-foot (116 m) tall structure that held 400,000 US gallons (1,500,000 L) of water. It
1660-405: A complicated air filtration system to ensure the nickel was not contaminated. By the war's end, Chrysler had built and shipped more than 3,500 diffusers. The gaseous diffusion process required suitable pumps that had to meet stringent requirements. Like the diffusers, the pumps had to resist corrosion from the uranium hexafluoride feed. Corrosion would not only damage the pumps, it would contaminate
1826-432: A constant 120 hertz. The first coal-fired boiler was started on 7 April 1944, followed by the second on 14 July and the third on 2 November. Each produced 750,000 pounds (340,000 kg) of steam per hour 1,325 pounds per square inch (9,140 kPa) and 935 °F (502 °C). To obtain the fourteen turbine generators needed, Groves had to use the Manhattan Project's priority to overrule Julius Albert Krug ,
SECTION 10
#17327867460641992-465: A fee of $ 216,000 for services up to the end of June 1945. The contract was terminated early on 1 May 1945, when Union Carbide took over the plant. Ford, Bacon & Davis was therefore paid $ 202,000. The other exception was the fluorine plant. Hooker Chemical was asked to supervise its construction of the fluorine plant and initially to operate it for a fixed fee of $ 24,500. The plant was turned over to Union Carbide on 1 February 1945. Part of
2158-716: A fission bomb was theoretically possible. The properties of pure uranium-235 were relatively unknown, as were those of plutonium, which had only been isolated by Glenn Seaborg and his team in February 1941. The scientists at the July 1942 conference envisioned creating plutonium in nuclear reactors where uranium-238 atoms absorbed neutrons that had been emitted from fissioning uranium-235. At this point no reactor had been built, and only tiny quantities of plutonium were available from cyclotrons . Even by December 1943, only two milligrams had been produced. There were many ways of arranging
2324-884: A liaison office in Washington, D.C., but established his temporary headquarters at 270 Broadway in New York, where he could draw on administrative support from the Corps of Engineers' North Atlantic Division . It was close to the Manhattan office of Stone & Webster , the principal project contractor, and to Columbia University. He had permission to draw on his former command, the Syracuse District, for staff, and he started with Lieutenant Colonel Kenneth Nichols , who became his deputy. Because most of his task involved construction, Marshall worked in cooperation with
2490-736: A lower enrichment which could be fed into the calutrons of the Y-12 electromagnetic plant . Urey therefore began preparations to mass-produce the Norris-Adler barrier, despite its problems. Meanwhile, Union Carbide and Kellex had made researchers at the Bakelite Corporation, a subsidiary of Union Carbide, aware of Nix's unsuccessful efforts with powdered nickel barriers. To Frazier Groff and other researchers at Bakelite's laboratories in Bound Brook, New Jersey , it seemed that Nix
2656-486: A meeting called by Stimson, which established a Military Policy Committee, responsible to the Top Policy Group, consisting of Bush (with Conant as an alternate), Styer and Rear Admiral William R. Purnell . Tolman and Conant were later appointed as Groves' scientific advisers. On 19 September, Groves went to Donald Nelson , the chairman of the War Production Board, and asked for broad authority to issue
2822-739: A new facility to produce the new barrier in just four months, produce all the barriers required in another four and have the production facility up and running in just twelve "would be something of a miraculous achievement". On 16 January 1944, Groves ruled in favor of the Johnson barrier. Johnson built a pilot plant for the new process at the Nash Building. Taylor analyzed the sample barriers produced and pronounced only 5 percent of them to be of acceptable quality. Edward Mack Jr. created his own pilot plant at Schermerhorn Hall at Columbia, and Groves obtained 80 short tons (73 t) of nickel from
2988-500: A new factory to produce the pumps, even though the pump design was still uncertain. The SAM Laboratories came up with a design, and Westinghouse built some prototypes that were successfully tested. Then Judson Swearingen at the Elliott Company came up with a revolutionary and promising design that was mechanically stable with seals that would contain the gas. This design was manufactured by Allis-Chalmers. Difficulties with
3154-578: A plant, much less four of them for $ 90 million." A single TNT plant that Nichols had recently built in Pennsylvania had cost $ 128 million. Nor were they impressed with estimates to the nearest order of magnitude, which Groves compared with telling a caterer to prepare for between ten and a thousand guests. A survey team from Stone & Webster had already scouted a site for the production plants. The War Production Board recommended sites around Knoxville, Tennessee , an isolated area where
3320-563: A porous barrier containing a mixture of two gases, the lighter molecules will pass out of the container more rapidly than the heavier molecules. The gas leaving the container is slightly enriched in the lighter molecules, while the residual gas is slightly depleted. A container wherein the enrichment process takes place through gaseous diffusion is called a diffuser . Gaseous diffusion had been used to separate isotopes before. Francis William Aston had used it to partially separate isotopes of neon in 1931, and Gustav Ludwig Hertz had improved on
3486-504: A possible source of bombs with a destructiveness vastly greater than anything now known." In February 1940, the U.S. Navy awarded Columbia University $ 6,000, most of which Fermi and Szilard spent on graphite . A team of Columbia professors including Fermi, Szilard, Eugene T. Booth and John Dunning created the first nuclear fission reaction in the Americas, verifying the work of Hahn and Strassmann. The same team subsequently built
SECTION 20
#17327867460643652-479: A prototype in a building built within a building, and found that it could be done, so long as the series of pickling and scaling steps required were done without anything coming in contact with oxygen. Chrysler's entire factory at Lynch Road in Detroit was turned over to the manufacture of diffusers. The electroplating process required over 50,000 square feet (4,600 m) of floor space, several thousand workers and
3818-480: A ranch. On 16 November 1942, Oppenheimer, Groves, Dudley and others toured the vicinity of the Los Alamos Ranch School . Oppenheimer expressed a strong preference for the site, citing its natural beauty, which, it was hoped, would inspire those working on the project. The engineers were concerned about the poor access road, and whether the water supply would be adequate, but otherwise felt that it
3984-469: A reaction becomes self-sustaining became known as "going critical". Compton reported the success to Conant in Washington, D.C., by a coded phone call, saying, "The Italian navigator [Fermi] has just landed in the new world." In January 1943, Grafton's successor, Major Arthur V. Peterson , ordered Chicago Pile-1 dismantled and reassembled at the Argonne Forest site, as he regarded the operation of
4150-619: A reactor as too hazardous for a densely populated area. The new site, still operated by the Metallurgical Laboratory, became known as ' Site A '. Chicago Pile-3 , the first heavy water reactor, also went critical at this site, on 15 May 1944. After the war, operations at Site A were moved about 6 miles (9.7 km) to DuPage County , the current location of the Argonne National Laboratory . By December 1942 there were concerns that even Oak Ridge
4316-406: A section. Similarly, the sections could be operated separately or as part of a single cascade. When completed, there were 2,892 stages. The basement housed the auxiliary equipment, such as the transformers, switch gears, and air conditioning systems. The ground floor contained the cells. The third level contained the piping. The fourth floor was the operating floor, which contained the control room and
4482-534: A self-contained and autonomous entity. Percival C. Keith, Kellogg's vice president of engineering, was placed in charge of Kellex. He drew extensively on Kellogg to staff the new company but also had to recruit staff from outside. Eventually, Kellex would have over 3,700 employees. Dunning remained in charge at Columbia until 1 May 1943, when the Manhattan District took over the contract from OSRD. By this time Slack's group had nearly 50 members. His
4648-684: A series of prototype nuclear reactors (or "piles" as Fermi called them) in Pupin Hall at Columbia but were not yet able to achieve a chain reaction. The Advisory Committee on Uranium became the National Defense Research Committee (NDRC) on Uranium when that organization was formed on 27 June 1940. On 28 June 1941, Roosevelt signed Executive Order 8807, which created the Office of Scientific Research and Development (OSRD), under director Vannevar Bush . The office
4814-413: A shortage of accommodations in the area made commuting long and difficult, which in turn made it difficult to find and retain workers. Thus construction workers were housed in large hutment and trailer camps. The J. A. Jones camp for K-25 workers, known as Happy Valley, held 15,000 people. This required 8 dormitories, 17 barracks, 1,590 hutments, 1,153 trailers and 100 Victory Houses. A pumping station
4980-550: A simpler gun-type design called Little Boy was developed that used uranium-235 . Three methods were employed for uranium enrichment : electromagnetic , gaseous , and thermal . In parallel with the work on uranium was an effort to produce plutonium. After the feasibility of the world's first artificial nuclear reactor, the Chicago Pile-1 , was demonstrated in 1942 at the Metallurgical Laboratory in
5146-425: A slightly enriched product. This could then be fed into K-25 or the calutrons at Y-12. Kellex estimated that using the enriched feed from K-27 could lift the output from K-25 from 35 to 60 percent uranium-235. Construction started at K-27 on 3 April 1945 and was completed in December 1945. The five drum warehouses were moved by truck to make way for K-27. The construction work was expedited by making it "virtually
K-25 - Misplaced Pages Continue
5312-407: A small amount of highly enriched product through running them in series. By early 1946, with K-27 in operation, the facility was producing 3.6 kilograms (7.9 lb) per day, enriched to 30 percent. The next step was to increase the enrichment further to 60 percent. This was achieved on 20 July 1946. This presented a problem, because Y-12 was not equipped to handle feed that was so highly enriched, but
5478-524: A special account not subject to the usual auditing and controls was used to hold Trust monies. Between 1944 and his resignation from the Trust in 1947, Groves deposited a total of $ 37.5 million. Groves appreciated the early British atomic research and the British scientists' contributions to the Manhattan Project but stated that the United States would have succeeded without them, although not in time for
5644-450: A special cleanliness unit on 18 April 1944. Buildings were completely sealed off, air was filtered, and all cleaning was with vacuum cleaners and mopping. Workers wore white lint-free gloves. At the peak of construction activity in May 1945, 25,266 people were employed on the site. Although by far the largest, the main process building (K-300) was but one of many that made up the facility. There
5810-525: Is an oxidant and a Lewis acid which is able to bind to fluoride . It reacts with water to form a solid compound and is very difficult to handle on an industrial scale. Booth, Dunning and von Grosse investigated the gaseous diffusion process. In 1941, they were joined by Francis G. Slack from Vanderbilt University and Willard F. Libby from the University of California . In July 1941, an Office of Scientific Research and Development (OSRD) contract
5976-479: Is likely to be started." In Serber's account, Oppenheimer mentioned the possibility of this scenario to Arthur Compton , who "didn't have enough sense to shut up about it. It somehow got into a document that went to Washington" and was "never laid to rest". The Chief of Engineers , Major General Eugene Reybold , selected Colonel James C. Marshall to head the Army's part of the project in June 1942. Marshall created
6142-417: Is solely the difference in weights of the uranium isotopes. For these reasons, UF 6 was the only choice as a feedstock for the gaseous diffusion process. Uranium hexafluoride, a solid at room temperature, sublimes at 56.5 °C (133.7 °F) at 1 standard atmosphere (100 kPa). Applying Graham's law to uranium hexafluoride: where: Uranium hexafluoride is a highly corrosive substance . It
6308-777: The Belgian Government in Exile was in London. Britain agreed to give the United States most of the Belgian ore, as it could not use most of the supply without restricted American research. In 1944, the Trust purchased 3,440,000 pounds (1,560,000 kg) of uranium oxide ore from companies operating mines in the Belgian Congo. To avoid briefing US Secretary of the Treasury Henry Morgenthau Jr. ,
6474-565: The Bell Telephone Laboratories experimented with nickel powder, while Edward O. Norris at the C. O. Jelliff Manufacturing Corporation and Edward Adler at the City College of New York worked on a design with electroplated nickel. Norris was an English interior decorator who had developed a very fine metal mesh for use with a spray gun . The design appeared too brittle and fragile for the proposed use, particularly on
6640-581: The Carnegie Institution of Washington and later the Naval Research Laboratory . Murphree also headed an unsuccessful separation project using gas centrifuges . Meanwhile, there were two lines of investigation into nuclear reactor technology : Harold Urey researched heavy water at Columbia, while Arthur Compton organized the Metallurgical Laboratory in early 1942 to study plutonium and reactors using graphite as
6806-534: The Chief of Staff of the Army , General George C. Marshall . Roosevelt chose the Army to run the project rather than the Navy, because the Army had more experience with managing large-scale construction. He agreed to coordinate the effort with the British and on 11 October sent a message to Prime Minister Winston Churchill , suggesting that they correspond on atomic matters. The S-1 Committee meeting on 18 December 1941
K-25 - Misplaced Pages Continue
6972-502: The Clinton Engineer Works (CEW) in early 1943. While Stone & Webster concentrated on the production facilities, the architectural and engineering firm Skidmore, Owings & Merrill developed a residential community for 13,000. The community was located on the slopes of Black Oak Ridge, from which the new town of Oak Ridge got its name. The Army presence at Oak Ridge increased in August 1943 when Nichols replaced Marshall as head of
7138-543: The International Nickel Company . With plenty of nickel to work with, by April 1944 both pilot plants were producing barriers of acceptable quality at a 45 percent rate. The project site chosen was at the Clinton Engineer Works in Tennessee. The area was inspected by representatives of the Manhattan District, Kellex and Union Carbide on 18 January 1943. Consideration was also given to sites near
7304-498: The Los Alamos Laboratory required 95 percent. For a time, product was mixed with feed to reduce the enrichment to 30 percent. Taking the concentration up to 95 percent raised safety concerns, as there was the risk of a criticality accident . After some deliberation, with opinions sought and obtained from Percival Keith, Norris Bradbury , Darol Froman , Elmer E. Kirkpatrick , Kenneth Nichols and Edward Teller , it
7470-763: The Shasta Dam in California and the Big Bend of the Columbia River in Washington state. The lower humidity of these areas made them more suitable for a gaseous diffusion plant, but the Clinton Engineer Works site was immediately available and otherwise suitable. Groves decided on the site in April 1943. Under the contract, Kellex had responsibility not just for the design and engineering of
7636-605: The Tennessee Valley Authority could supply ample electric power and the rivers could provide cooling water for the reactors. After examining several sites, the survey team selected one near Elza, Tennessee . Conant advised that it be acquired at once and Styer agreed but Marshall temporized, awaiting the results of Conant's reactor experiments. Of the prospective processes, only Lawrence's electromagnetic separation appeared sufficiently advanced for construction to commence. Marshall and Nichols began assembling
7802-426: The University of Birmingham had made a breakthrough investigating the critical mass of uranium-235 in June 1939. Their calculations indicated that it was within an order of magnitude of 10 kilograms (22 lb), small enough to be carried by contemporary bombers. Their March 1940 Frisch–Peierls memorandum initiated the British atomic bomb project and its MAUD Committee , which unanimously recommended pursuing
7968-523: The University of Birmingham in Britain, the Australian physicist Mark Oliphant assigned two refugee physicists—Otto Frisch and Rudolf Peierls —the task of investigating the feasibility of an atomic bomb, ironically because their status as enemy aliens precluded their working on secret projects like radar . Their March 1940 Frisch–Peierls memorandum indicated that the critical mass of uranium-235
8134-935: The University of Chicago , the project designed the X-10 Graphite Reactor and the production reactors at the Hanford Site , in which uranium was irradiated and transmuted into plutonium. The Fat Man plutonium implosion-type weapon was developed in a concerted design and development effort by the Los Alamos Laboratory. The project was also charged with gathering intelligence on the German nuclear weapon project . Through Operation Alsos , Manhattan Project personnel served in Europe, sometimes behind enemy lines, where they gathered nuclear materials and documents, and rounded up German scientists. Despite
8300-508: The isotopes of uranium , measurements that were used by Fritz Houtermans and Arthur Holmes in the 1940s to estimate the age of the Earth . Nier returned to Minnesota in 1938 to be near his ageing parents. In 1940, on the request of Enrico Fermi , he and a few students, including Edward Ney , prepared a pure sample of uranium-235 using an early mass spectrograph designed by Nier, for John R. Dunning 's team at Columbia University . On
8466-424: The liquid drop model of the atomic nucleus to explain the mechanism of nuclear fission. As the experimental physicists studied fission, they uncovered puzzling results. George Placzek asked Bohr why uranium seemed to fission with both fast and slow neutrons . Walking to a meeting with Wheeler, Bohr had an insight that the fission at low energies was caused by the uranium-235 isotope , while at high energies it
SECTION 50
#17327867460648632-604: The Army allowed the crops to be harvested, but this was not always possible. The land acquisition process dragged on and was not completed before the end of the Manhattan Project in December 1946. The dispute did not delay work. Although progress on the reactor design at Metallurgical Laboratory and DuPont was not sufficiently advanced to accurately predict the scope of the project, a start was made in April 1943 on facilities for an estimated 25,000 workers, half of whom were expected to live on-site. By July 1944, some 1,200 buildings had been erected and nearly 51,000 people were living in
8798-621: The Army's component the Manhattan District; Reybold officially created this district on 13 August. Informally, it was known as the Manhattan Engineer District, or MED. Unlike other districts, it had no geographic boundaries, and Marshall had the authority of a division engineer. Development of Substitute Materials remained as the official codename of the project as a whole but was supplanted over time by "Manhattan". Marshall later conceded that, "I had never heard of atomic fission but I did know that you could not build much of
8964-625: The August 1945 bombing of Hiroshima. The British wartime participation was crucial to the success of the United Kingdom's independent nuclear weapons program after the war when the McMahon Act of 1946 temporarily ended American nuclear cooperation. The day after he took over the project, Groves went to Tennessee with Colonel Marshall to inspect the proposed site there, and Groves was impressed. On 29 September 1942, United States Under Secretary of War Robert P. Patterson authorized
9130-746: The Australian physicist Mark Oliphant , flew to the US in late August 1941 and discovered that data provided by the MAUD Committee had not reached key American physicists. Oliphant set out to find out why the committee's findings were apparently being ignored. He met with the Uranium Committee and visited Berkeley, California , where he spoke persuasively to Ernest O. Lawrence . Lawrence was sufficiently impressed to commence his own research into uranium. He in turn spoke to James B. Conant , Arthur H. Compton and George B. Pegram . Oliphant's mission
9296-428: The Clinton Engineer Works' needs, there was unease about relying on a single supplier when a power failure could cost the gaseous diffusion plant weeks of work, and the lines to TVA could be sabotaged. A local plant was more secure. The Kellex engineers were also attracted to the idea of being able to generate the variable frequency current required by the gaseous diffusion process without complicated transformers. A site
9462-609: The Corps of Engineers to acquire 56,000 acres (23,000 ha) of land by eminent domain at a cost of $ 3.5 million. An additional 3,000 acres (1,200 ha) was subsequently acquired. About 1,000 families were affected by the order, which came into effect on 7 October. Protests, legal appeals, and a 1943 Congressional inquiry were to no avail. By mid-November U.S. Marshals were posting notices to vacate on farmhouse doors, and construction contractors were moving in. Some families were given two weeks' notice to vacate farms that had been their homes for generations. The ultimate cost of
9628-568: The Harshaw Chemical Company, the gaseous diffusion plant would take the product of the S-50 thermal diffusion plant, with an average enrichment of about 0.85 percent. Product enrichment continued to improve as more stages came online and performed better than anticipated. By June product was being enriched to 7 percent; by September it was 23 percent. The S-50 plant ceased operation on 9 September, and Kellex transferred
9794-431: The K-25 plant, but for its construction as well. The prime construction contractor was J. A. Jones Construction from Charlotte, North Carolina . It had impressed Groves with its work on several major Army construction projects, such as Camp Shelby, Mississippi . There were more than sixty subcontractors. Kellex engaged another construction company, Ford, Bacon & Davis, to build the fluorine and nitrogen facilities, and
9960-460: The K-300 complex was taken over by Union Carbide in August 1944 and was run as a pilot plant, training operators and developing procedures, using nitrogen instead of uranium hexafluoride until October 1944, and then perfluoroheptane until April 1945. The design of the gaseous diffusion plant allowed for it to be completed in sections and for the sections to be put into operation while work continued on
10126-606: The Manhattan Engineer District. One of his first tasks was to move the district headquarters to Oak Ridge, although the name of the district did not change. In September 1943 the administration of community facilities was outsourced to Turner Construction Company through a subsidiary, the Roane-Anderson Company. Chemical engineers were part of "frantic efforts" to make 10% to 12% enriched uranium 235, with tight security and fast approvals for supplies and materials. The population of Oak Ridge soon expanded well beyond
SECTION 60
#173278674606410292-821: The Manhattan Project conducted weapons testing at Bikini Atoll as part of Operation Crossroads , developed new weapons, promoted the development of the network of national laboratories , supported medical research into radiology and laid the foundations for the nuclear navy . It maintained control over American atomic weapons research and production until the formation of the United States Atomic Energy Commission (AEC) in January 1947. The discovery of nuclear fission by Otto Hahn and Fritz Strassmann in 1938, and its theoretical explanation by Lise Meitner and Otto Frisch , made an atomic bomb theoretically possible. There were fears that
10458-524: The Manhattan Project's emphasis on security, Soviet atomic spies penetrated the program. The first nuclear device ever detonated was an implosion-type bomb during the Trinity test , conducted at White Sands Proving Ground in New Mexico on 16 July 1945. Little Boy and Fat Man bombs were used a month later in the atomic bombings of Hiroshima and Nagasaki , respectively. In the immediate postwar years,
10624-403: The Metallurgical Laboratory, was assigned to assist Oppenheimer by coordinating experimental physics groups scattered across the country. Oppenheimer and Robert Serber of the University of Illinois examined the problems of neutron diffusion—how neutrons moved in a nuclear chain reaction—and hydrodynamics —how the explosion produced by a chain reaction might behave. To review this work and
10790-470: The Norris-Adler barrier, realized that they could also be taken with the Bakelite barrier. The result was a barrier better than either, although still short of what was required. At a meeting at Columbia with the Army in attendance on 20 October 1943, Keith proposed switching the development effort to the Johnson barrier. Urey balked at this, fearing this would destroy morale at the SAM Laboratories. The issue
10956-470: The President, who approved it by writing "OK FDR" on the document. Compton asked theoretical physicist J. Robert Oppenheimer of the University of California to take over research into fast neutron calculations —key to calculations of critical mass and weapon detonation—from Gregory Breit , who had quit on 18 May 1942 because of concerns over lax operational security. John H. Manley , a physicist at
11122-726: The Quebec Agreement, the Americans' progress and expenditures amazed the British. Chadwick pressed for British involvement in the Manhattan Project to the fullest extent and abandoned hopes of an independent British project during the war. With Churchill's backing, he attempted to ensure that every request from Groves for assistance was honored. The British Mission that arrived in the United States in December 1943 included Niels Bohr , Otto Frisch, Klaus Fuchs , Rudolf Peierls, and Ernest Titterton . More scientists arrived in early 1944. While those assigned to gaseous diffusion left by
11288-406: The academic scientists working on the project. Groves' orders placed him directly under Somervell rather than Reybold, with Colonel Marshall now answerable to Groves. Groves established his headquarters in Washington, D.C., in the New War Department Building , where Colonel Marshall had his liaison office. He assumed command of the Manhattan Project on 23 September 1942. Later that day, he attended
11454-403: The aim of developing the means to separate kilogram amounts of uranium-235. At a lunch on 21 May 1940, George B. Kistiakowsky suggested the possibility of using gaseous diffusion . Gaseous diffusion is based on Graham's law , which states that the rate of effusion of a gas through a porous barrier is inversely proportional to the square root of the gas's molecular mass . In a container with
11620-399: The air. The nitrogen plant (K-1408) provided gas for use as a pump sealant and to protect equipment from moist air. The fluorine generating plant (K-1300) generated, bottled and stored fluorine. It had not been in great demand before the war, and Kellex and the Manhattan District considered four different processes for large-scale production. A process developed by the Hooker Chemical Company
11786-433: The bedrock, but this would have required thousands of caissons. To save time, soil compaction and shallow footings were used instead. Layers were laid down and compacted with sheepsfoot rollers in the areas that had to be filled, and the footings were laid over compacted soil in the low-lying areas and the undisturbed soil in the areas that had been excavated. Activities overlapped, so concrete pouring began while grading
11952-705: The bomb design team at Los Alamos needed them, despite the risk of revealing weapon design secrets. In August 1943 Churchill and Roosevelt negotiated the Quebec Agreement , which established the Combined Policy Committee to coordinate the efforts of the US and UK; Canada was not a signatory, but the Agreement provided for a Canadian representative on the Combined Policy Committee in view of Canada's contribution to
12118-713: The branch office in Santa Fe, where she met new arrivals and issue them with passes. An Army-OSRD council on 25 June 1942 decided to build a pilot plant for plutonium production in the Argonne Forest preserve , southwest of Chicago. In July, Nichols arranged for a lease of 1,025 acres (415 ha) from the Cook County Forest Preserve District , and Captain James F. Grafton was appointed Chicago area engineer. It soon became apparent that
12284-410: The conditioning plant. Construction work was initially the responsibility of Lieutenant Colonel Warren George, the chief of the construction division of the Clinton Engineer Works. Major W. P. Cornelius became the construction officer responsible for K-25 works on 31 July 1943. He was answerable to Stowers back in Manhattan. He became chief of the construction division on 1 March 1946. J. J. Allison
12450-402: The construction camp. As area engineer, Matthias exercised overall control of the site. At its peak, the construction camp was the third most populous town in Washington state. Hanford operated a fleet of over 900 buses, more than the city of Chicago. Like Los Alamos and Oak Ridge, Richland was a gated community with restricted access, but it looked more like a typical wartime American boomtown:
12616-461: The contract to build the diffusers to Chrysler . In turn Chrysler president K. T. Keller assigned Carl Heussner, an expert in electroplating , the task of developing a process for electroplating such a large object. Senior Chrysler executives called this "Project X-100". Electroplating used one-thousandth of the amount of nickel needed for a solid nickel diffuser. The SAM Laboratories had already attempted this and failed. Heussner experimented with
12782-455: The day of its receipt (it was sent by US Postal Mail), Dunning's team was able to demonstrate that uranium-235 was the isotope responsible for nuclear fission , rather than the more abundant uranium-238 . Confirmation of this suspected fact was a critical step in the development of the atomic bomb . From 1943 to 1945, Nier worked with Kellex Corporation in Manhattan, New York City on
12948-477: The design and construction of a ten-stage pilot gaseous diffusion plant. On 14 December 1942, the Manhattan District, the US Army component of the Manhattan Project (as the effort to develop an atomic bomb became known) contracted Kellogg to design, build and operate a full-scale production plant. Unusually, the contract did not require any guarantees from Kellogg that it could actually accomplish this task. Because
13114-469: The design and development of efficient and effective mass spectrographs for use in the Manhattan Project to build the atomic bomb in World War II . During the war most of the spectrographs used for monitoring uranium separations were designed by Nier. After the war, he returned to Minnesota where he worked on geochronology , the upper atmosphere , space science and noble gases . Nier designed
13280-471: The deuterium concentration in the water from 2.3% to 99.8%. For this process, Hugh Taylor of Princeton developed a platinum-on-carbon catalyst for the first three stages while Urey developed a nickel- chromia one for the fourth stage tower. The final cost was $ 2.8 million. The Canadian Government did not officially learn of the project until August 1942. Trail's heavy water production started in January 1944 and continued until 1956. Heavy water from Trail
13446-552: The development of an atomic bomb. In July 1940, Britain had offered to give the United States access to its research, and the Tizard Mission 's John Cockcroft briefed American scientists on British developments. He discovered that the American project was smaller than the British, and not as advanced. As part of the scientific exchange, the MAUD Committee's findings were conveyed to the United States. One of its members,
13612-411: The diffusers and pumps paled in significance beside those with the porous barrier . To work, the gaseous diffusion process required a barrier with microscopic holes, but not subject to plugging. It had to be porous but strong enough to handle the high pressures. And, like everything else, it had to resist corrosion from uranium hexafluoride. The latter criterion suggested a nickel barrier. Foster C. Nix at
13778-494: The director of the Office of War Utilities. The turbine generators had a combined output of 238,000 kilowatts. The power plant could also receive power from TVA. It was decommissioned in the 1960s and demolished in 1995. A site for the K-25 facility was chosen near the high school of the town of Wheat . As the dimensions of the K-25 facility became more apparent, it was decided to move it to a larger site near Poplar Creek, closer to
13944-482: The efficiency of the bomb as it exploded. As the idea of the fission bomb was theoretically settled—at least until more experimental data was available—Edward Teller pushed for discussion of a more powerful bomb: the "super", now usually referred to as a " hydrogen bomb ", which would use the force of a detonating fission bomb to ignite a nuclear fusion reaction in deuterium and tritium . Teller proposed scheme after scheme, but Bethe refused each one. The fusion idea
14110-559: The effort. An agreement between Roosevelt and Churchill known as the Hyde Park Aide-Mémoire , signed in late September 1944, extended the Quebec Agreement to the postwar period and suggested that "when a 'bomb' is finally available, it might perhaps, after mature consideration, be used against the Japanese, who should be warned that this bombardment will be repeated until they surrender". When cooperation resumed after
14276-418: The fall of 1944, the thirty-five working under Oliphant with Lawrence at Berkeley were assigned to existing laboratory groups and most stayed until the end of the war. The nineteen sent to Los Alamos also joined existing groups, primarily related to implosion and bomb assembly, but not the plutonium-related ones. The Quebec Agreement specified that nuclear weapons would not be used against another country without
14442-438: The feed. There could be no leakage of uranium hexafluoride (especially if it was already enriched) or of oil, which would react with the uranium hexafluoride. The pumps needed to operate at high rates and handle a gas 12 times as dense as air. To meet these requirements, the SAM Laboratories chose to use centrifugal pumps . The desired compression ratio of 2.3:1 to 3.2:1 was unusually high for this type of pump. For some purposes,
14608-500: The first Canadian reactor, and the first to be completed outside the United States, when it went critical in September 1945; ZEEP remained in use by researchers until 1970. A larger 10 MW NRX reactor, which was designed during the war, was completed and went critical in July 1947. The Eldorado Mine at Port Radium was a source of uranium ore. Alfred O. C. Nier Alfred Otto Carl Nier (May 28, 1911 – May 16, 1994)
14774-422: The fissile material into a critical mass. The simplest was shooting a "cylindrical plug" into a sphere of "active material" with a "tamper"—dense material to focus neutrons inward and keep the reacting mass together to increase its efficiency. They also explored designs involving spheroids , a primitive form of " implosion " suggested by Richard C. Tolman , and the possibility of autocatalytic methods to increase
14940-652: The gaseous diffusion plant. Despite this progress, the K-25 Project was in serious trouble without a suitable barrier, and by August 1943 it was facing cancellation. On 13 August Groves informed the Military Policy Committee (the senior committee that steered the Manhattan Project) that gaseous diffusion enrichment in excess of fifty percent was probably infeasible, and the gaseous diffusion plant would be limited to producing product with
15106-549: The gaseous diffusion process. Before this could be done, the Special Alloyed Materials (SAM) Laboratories at Columbia University and the Kellex Corporation had to overcome formidable difficulties to develop a suitable barrier. Fluorine consists of only a single natural isotope F , so the 1 percent difference in molecular weights between UF 6 and UF 6
15272-520: The general theory of fission reactions, Oppenheimer and Fermi convened meetings at the University of Chicago in June and at the University of California in July 1942 with theoretical physicists Hans Bethe , John Van Vleck , Edward Teller, Emil Konopinski , Robert Serber, Stan Frankel , and Eldred C. (Carlyle) Nelson, and experimental physicists Emilio Segrè , Felix Bloch , Franco Rasetti , Manley, and Edwin McMillan . They tentatively confirmed that
15438-401: The head of the Corps of Engineers Construction Division, Major General Thomas M. Robbins , and his deputy, Colonel Leslie Groves . Reybold, Somervell, and Styer decided to call the project "Development of Substitute Materials", but Groves felt that this would draw attention. Since engineer districts normally carried the name of the city where they were located, Marshall and Groves agreed to name
15604-524: The higher stages of enrichment, but there was hope that this could be overcome. In 1943, Urey brought in Hugh S. Taylor from Princeton University to look at the problem of a usable barrier. Libby made progress on understanding the chemistry of uranium hexafluoride, leading to ideas on how to prevent corrosion and plugging. Chemical researchers at the SAM Laboratories studied fluorocarbons , which resisted corrosion and could be used as lubricants and coolants in
15770-411: The highest rating he could assign was AA-3, although he was willing to provide a AAA rating on request for critical materials if the need arose. Nichols and Marshall were disappointed; AA-3 was the same priority as Nichols' TNT plant in Pennsylvania. Vannevar Bush became dissatisfied with Colonel Marshall's failure to get the project moving forward expeditiously and felt that more aggressive leadership
15936-900: The hundreds of instrument panels. From here, the operators monitored the process. The first section was ready for test runs on 17 April 1944, although the barriers were not yet ready to be installed. The main process building surpassed The Pentagon as the largest building in the world, with a floor area of 5,264,000 square feet (489,000 m), and an enclosed volume of 97,500,000 cubic feet (2,760,000 m). Construction required 200,000 cubic yards (150,000 m) of concrete and 100 miles (160 km) of gas pipes. Because uranium hexafluoride corrodes steel and steel piping had to be coated in nickel, smaller pipes were made of copper or monel . The equipment operated under vacuum pressures, so plumbing had to be air tight. Special efforts were made to create as clean an environment as possible to areas where piping or fixtures were being installed. J. A. Jones established
16102-533: The importance of top priority. Most everything proposed in the Roosevelt administration would have top priority. That would last for about a week or two and then something else would get top priority". One of Groves' early problems was to find a director for Project Y , the group that would design and build the bomb. The obvious choice was one of the three laboratory heads, Urey, Lawrence, or Compton, but they could not be spared. Compton recommended Oppenheimer, who
16268-498: The industrial manufacturing area of Ontario and Quebec, and proximity to a rail head adjacent to a large military base, Camp Petawawa . Located on the Ottawa River, it had access to abundant water. The first director of the new laboratory was Hans von Halban . He was replaced by John Cockcroft in May 1944, who was succeeded by Bennett Lewis in September 1946. A pilot reactor known as ZEEP (zero-energy experimental pile) became
16434-425: The initial plans, and peaked at 75,000 in May 1945, by which time 82,000 people were employed at the Clinton Engineer Works, and 10,000 by Roane-Anderson. The idea of locating Project Y at Oak Ridge was considered, but it was decided that it should be in a remote location. On Oppenheimer's recommendation, the search for a suitable site was narrowed to the vicinity of Albuquerque, New Mexico , where Oppenheimer owned
16600-491: The issues involved in setting up a laboratory in a remote area and should be appointed as its director. Groves personally waived the security requirements and issued Oppenheimer's clearance on 20 July 1943. The British and Americans exchanged nuclear information but did not initially combine their efforts; during 1940-41 the British project ( Tube Alloys ) was larger and more advanced. Britain rebuffed attempts by Bush and Conant in August 1941 to strengthen cooperation because it
16766-535: The land acquisition, which was not completed until March 1945, was only about $ 2.6 million—around $ 47 an acre. When presented with a proclamation declaring Oak Ridge a total exclusion area that no one could enter without military permission, the Governor of Tennessee , Prentice Cooper , angrily tore it up. Initially known as the Kingston Demolition Range, the site was officially renamed
16932-476: The last unit to Union Carbide on 11 September. Highly enriched uranium was used in the Little Boy atomic bomb used in the bombing of Hiroshima on 6 August. With the end of the war in August 1945, the Manhattan Project's priority shifted from speed to economy and efficiency. The cascades were configurable, so they could produce a large amount of slightly enriched product by running them in parallel, or
17098-471: The method to almost completely separate neon by running it through a series of stages. In the United States, William D. Harkins had used it to separate chlorine . Kistiakowsky was familiar with the work of Charles G. Maier at the Bureau of Mines , who had also used the process to separate gases. Uranium hexafluoride ( UF 6 ) was the only known compound of uranium sufficiently volatile to be used in
17264-488: The military necessity continues". Wartime land purchases eventually came to 49,383 acres (19,985 ha), but only $ 414,971 was spent. Work commenced in December 1942. Groves initially allocated $ 300,000 for construction, three times Oppenheimer's estimate, but by the time Sundt finished on 30 November 1943, over $ 7 million had been spent. During the war, Los Alamos was referred to as "Site Y" or "the Hill". Initially it
17430-551: The military profile was lower, and physical security elements like high fences and guard dogs were less evident. Canada provided research, extraction and production of uranium and plutonium, and Canadian scientists worked at Los Alamos. Cominco had produced electrolytic hydrogen at Trail, British Columbia , since 1930. Urey suggested in 1941 that it could produce heavy water. To the existing $ 10 million plant consisting of 3,215 cells consuming 75 MW of hydroelectric power, secondary electrolysis cells were added to increase
17596-799: The miniature mass spectrometers used by the Viking Landers to sample the atmosphere of Mars. Active to the end of his life, he died on May 16, 1994, two weeks after being paralysed in a motor accident. Nier was a member of the National Academy of Sciences , the American Philosophical Society , the American Academy of Arts and Sciences , and a foreign scientific member of the Max Planck Society . The Martian crater Nier and
17762-516: The mutual consent of the US and UK. In June 1945, Wilson agreed that the nuclear bombing of Japan would be recorded as a decision of the Combined Policy Committee. The Combined Policy Committee created the Combined Development Trust in June 1944, with Groves as its chairman, to procure uranium and thorium ores on international markets. The Belgian Congo and Canada held much of the world's uranium outside Eastern Europe, and
17928-403: The necessary resources. The first step was to obtain a high priority rating for the project. The top ratings were AA-1 through AA-4 in descending order, although there was a special AAA rating reserved for emergencies. Ratings AA-1 and AA-2 were for essential weapons and equipment, so Colonel Lucius D. Clay , the deputy chief of staff at Services and Supply for requirements and resources, felt that
18094-404: The others. J. A. Jones completed the first 60 stages by the end of 1944. Before each stage was accepted, it underwent tests by J. A. Jones, Carbide and Carbon, and SAM Laboratories technicians to verify that the equipment was working and there were no leaks. Between four and six hundred people devoted eight months to this testing. Perfluoroheptane was used as a test fluid until February 1945, when it
18260-602: The plant were represented by the Oil, Chemical and Atomic Workers International Union . K-25 became a prototype for other gaseous diffusion facilities established in the early post-war years. The first of these was the 374,000-square-foot (34,700 m) K-27 completed in September 1945. It was followed by the 15-acre (6.1 ha) K-29 in 1951, the 20-acre (8.1 ha) K-31 in 1951 and the 32-acre (13 ha) K-33 in 1954. Gaseous diffusion facilities were built at Paducah, Kentucky , in 1952, and Portsmouth, Ohio , in 1954. The K-25 plant
18426-462: The power plant. This site was approved on 24 June 1943. Considerable work was required to prepare the site. Existing roads in the area were improved to take heavy traffic. A 5.1-mile (8.2 km) road was built to connect the site to US Route 70 , and another, 5 miles (8.0 km) long, to connect with Tennessee State Route 61 . A ferry over the Clinch River was upgraded and then replaced with
18592-430: The practical difficulties were realized, this target was reduced to 36 percent. On the other hand, the cascade design meant construction did not need to be complete before the plant started operating. In August 1943, Kellex submitted a schedule that called for a capability to produce material enriched to 5 percent uranium-235 by 1 June 1945; 15 percent by 1 July; and 36 percent by 23 August. This schedule
18758-553: The research effort at Columbia, which became the Special Alloyed Materials (SAM) Laboratories. Urey was put in charge, Dunning becoming head of one of its divisions. It would remain this way until 1 March 1945, when the SAM Laboratories were taken over by Union Carbide . The expansion of the SAM Laboratories led to a search for more space. The Nash Garage Building at 3280 Broadway was purchased by Columbia University. Originally an automobile dealership, it
18924-611: The research of Enrico Fermi and others into nuclear chain reactions . They had it signed by Albert Einstein and delivered to President Franklin D. Roosevelt . Roosevelt called on Lyman Briggs of the National Bureau of Standards to head an Advisory Committee on Uranium ; Briggs met with Szilard, Wigner and Edward Teller in October 1939. The committee reported back to Roosevelt in November that uranium "would provide
19090-572: The scale of operations was too great for the area, and it was decided to build the pilot plant at Oak Ridge and keep a research and testing facility in Chicago. Delays in establishing the plant at Argonne led Arthur Compton to authorize the Metallurgical Laboratory to construct the first nuclear reactor beneath the bleachers of Stagg Field at the University of Chicago. The reactor required an enormous amount of highly purified graphite blocks and uranium in both metallic and powdered oxide forms. At
19256-483: The scope of the project was not well defined, Kellogg and the Manhattan District agreed to defer any financial details to a later, cost-plus contract , which was executed in April 1944. Kellogg was then paid $ 2.5 million. For security reasons, the Army had Kellogg establish a wholly-owned subsidiary, the Kellex Corporation , so the gaseous diffusion project could be kept separate from other company work. "Kell" stood for "Kellogg" and "X" for secret. Kellex operated as
19422-540: The site be located far from the existing uranium production facility at Oak Ridge. In December 1942, Groves dispatched Colonel Franklin Matthias and DuPont engineers to scout potential sites. Matthias reported that Hanford Site near Richland, Washington , was "ideal in virtually all respects". It was isolated and near the Columbia River , which could supply sufficient water to cool the reactors. Groves visited
19588-613: The site in January and established the Hanford Engineer Works (HEW), codenamed "Site W". Under Secretary Patterson gave his approval on 9 February, allocating $ 5 million for the acquisition of 430,000 acres (170,000 ha). The federal government relocated some 1,500 residents of nearby settlements, as well as the Wanapum and other tribes using the area. A dispute arose with farmers over compensation for crops, which had already been planted. Where schedules allowed,
19754-407: The surface, the power plant was supported on 40 concrete-filled caissons . Installation of the first boiler commenced in October 1943. Construction work was complete by late September. To prevent sabotage, the power plant was connected to the gaseous diffusion plant by an underground conduit. Despite this, there was one act of sabotage, in which a nail was driven through the electric cable. The culprit
19920-510: The term "K-25 plant" was being used for the plant that created it. That month, the term "K-25 Project" was applied to the entire project to develop uranium enrichment using the gaseous diffusion process. When other "K-" buildings were added after the war, "K-25" became the name of the original, larger complex. The highly corrosive nature of uranium hexafluoride presented several technological challenges. Pipes and fittings that it came into contact with had to be made of or clad with nickel . This
20086-528: The time, there was a limited source of pure uranium metal; Frank Spedding of Iowa State University was able to produce only two short tons . Three short tons was supplied by Westinghouse Lamp Plant , produced in a rush with makeshift process. A large square balloon was constructed by Goodyear Tire to encase the reactor. On 2 December 1942, a team led by Enrico Fermi initiated the first artificial self-sustaining nuclear chain reaction in an experimental reactor known as Chicago Pile-1 . The point at which
20252-438: The two countries were reversed, and in January 1943 Conant notified the British that they would no longer receive atomic information except in certain areas. The British investigated the possibility of an independent nuclear program but determined that it could not be ready in time to impact the war in Europe . By March 1943 Conant decided that James Chadwick and one or two other British scientists were important enough that
20418-709: The war, four more gaseous diffusion plants named K-27, K-29, K-31 and K-33 were added to the site. The K-25 site was renamed the Oak Ridge Gaseous Diffusion Plant in 1955. Production of enriched uranium ended in 1964, and gaseous diffusion finally ceased on the site on 27 August 1985. The Oak Ridge Gaseous Diffusion Plant was renamed the Oak Ridge K-25 Site in 1989 and the East Tennessee Technology Park in 1996. Demolition of all five gaseous diffusion plants
20584-576: Was "pervaded by an atmosphere of enthusiasm and urgency" in the wake of the attack on Pearl Harbor and the United States declaration of war on Japan and on Germany . Work was proceeding on three techniques for isotope separation : Lawrence and his team at the University of California investigated electromagnetic separation , Eger Murphree and Jesse Wakefield Beams 's team looked into gaseous diffusion at Columbia University , and Philip Abelson directed research into thermal diffusion at
20750-570: Was a conditioning building (K-1401), where piping and equipment were cleaned prior to installation. A feed purification building (K-101) was built to remove impurities from the uranium hexafluoride, but never operated as such because the suppliers provided feed pure enough to be fed into the gaseous diffusion process. The three-story surge and waste removal building (K-601) processed the "tail" stream of depleted uranium hexafluoride . The air conditioning building (K-1401) provided 76,500 cubic feet (2,170 m) per minute of clean, dry air. K-1201 compressed
20916-486: Was able to attend the nearby University of Minnesota . Though he graduated in electrical engineering in 1931, the lack of engineering jobs during the Great Depression encouraged him to take up graduate study in physics . In 1936, his spectroscopic skills won him a fellowship and substantial grant at Harvard University . His work there led to the 1938 publication of measurements of the relative abundance of
21082-573: Was already intimately familiar with the bomb design concepts. However, Oppenheimer had little administrative experience, and, unlike Urey, Lawrence, and Compton, had not won a Nobel Prize, which many scientists felt that the head of such an important laboratory should have. There were also concerns about Oppenheimer's security status, as many of his associates were communists , including his wife, Kitty ; his girlfriend, Jean Tatlock ; and his brother, Frank . A long conversation in October 1942 convinced Groves and Nichols that Oppenheimer thoroughly understood
21248-663: Was an American physicist who pioneered the development of mass spectrometry . He was the first to use mass spectrometry to isolate uranium-235 which was used to demonstrate that U could undergo fission and developed the sector mass spectrometer configuration now known as Nier-Johnson geometry. He was born in St. Paul, Minnesota on May 28, 1911. Nier showed an early ability in mathematics and science , coupled with an aptitude for craft and mechanical work. Nier's German immigrant parents had little education or financial resources but their determination for his development meant that he
21414-529: Was awarded to Columbia University to study gaseous diffusion. With the help of the mathematician Karl P. Cohen , they built a twelve-stage pilot gaseous diffusion plant at the Pupin Laboratories. Initial tests showed that the stages were not as efficient as the theory would suggest; they would need about 4,600 stages to enrich to 90 percent uranium-235. A secret contract was awarded to M. W. Kellogg for engineering studies in July 1941. This included
21580-402: Was built in 1944, the four-story K-25 gaseous diffusion plant was the world's largest building, comprising over 5,264,000 square feet (489,000 m) of floor space and a volume of 97,500,000 cubic feet (2,760,000 m). Construction of the K-25 facility was undertaken by J. A. Jones Construction . At the height of construction, over 25,000 workers were employed on the site. Gaseous diffusion
21746-544: Was built in 1958 by the Chicago Bridge and Iron Company and served as reservoir for the fire suppression system. Over 1.5 million pounds (680 tonnes) of steel was used in its construction. It operated until June 2013 and was demolished in August 2013. The preliminary specification for the K-25 plant in March 1943 called for it to produce 1 kilogram (2.2 lb) per day of product that was 90 percent uranium-235. As
21912-400: Was built to supply drinking water from the Clinch River, along with a water treatment plant. Amenities included a school, eight cafeterias, a bakery, theater, three recreation halls, a warehouse and a cold storage plant. Ford, Bacon & Davis established a smaller camp for 2,100 people. Responsibility for the camps was transferred to the Roane-Anderson Company on 25 January 1946, and the school
22078-463: Was but one of three enrichment technologies used by the Manhattan Project. Slightly enriched product from the S-50 thermal diffusion plant was fed into the K-25 gaseous diffusion plant. Its product in turn was fed into the Y-12 electromagnetic plant . The enriched uranium was used in the Little Boy atomic bomb used in the atomic bombing of Hiroshima . In 1946, the K-25 gaseous diffusion plant became capable of producing highly enriched product. After
22244-490: Was chosen for this on the western edge of the Clinton Engineer Works site where it could draw cold water from the Clinch River and discharge warm water into Poplar Creek without affecting the inflow. Groves approved this location on 3 May 1943. Surveying began on the power plant site on 31 May, and J. A. Jones started construction work the following day. Because the bedrock was 35 to 40 feet (11 to 12 m) below
22410-845: Was chosen. Owing to the hazardous nature of fluorine, it was decided that shipping it across the United States was inadvisable and it should be manufactured on site at the Clinton Engineer Works. Two pump houses (K-801 and K-802) and two cooling towers (H-801 and H-802) provided 135,000,000 US gallons (510 Ml) of cooling water per day for the motors and compressors. The administration building (K-1001) provided 2 acres (0.81 ha) of office space. A laboratory building (K-1401) contained facilities for testing and analyzing feed and product. Five drum warehouses (K-1025-A to -E) had 4,300 square feet (400 m) of floor space to store drums of uranium hexafluoride. There were also warehouses for general stores (K-1035), spare parts (K-1036), and equipment (K-1037). A cafeteria (K-1002) provided meal facilities, including
22576-578: Was co-located in the Woolworth Building. The Manhattan District had its offices nearby at 270 Broadway until it moved to Oak Ridge, Tennessee , in August 1943. The codename "K-25" was a combination of the "K" from Kellex, and "25", a World War II-era code designation for uranium-235 (an isotope of element 92, mass number 235). The term was first used in Kellex internal reports for the end product, enriched uranium, in March 1943. By April 1943,
22742-591: Was completed in February 2017. The discovery of the neutron by James Chadwick in 1932, followed by that of nuclear fission in uranium by German chemists Otto Hahn and Fritz Strassmann in 1938, and its theoretical explanation (and naming) by Lise Meitner and Otto Frisch soon after, opened up the possibility of a controlled nuclear chain reaction with uranium. At the Pupin Laboratories at Columbia University , Enrico Fermi and Leo Szilard began exploring how this might be achieved. Fears that
22908-428: Was decided that this could be done safely if appropriate precautions were taken. On 28 November 1946, the K-25 plant began producing 94 percent product. At this point, they ran into a serious flaw in the gaseous diffusion concept: enrichment in uranium-235 also enriched the product in the unwanted and fairly useless uranium-234, making it difficult to raise the enrichment to 95 percent. On 6 December 1946, production
23074-436: Was decided to use uranium hexafluoride despite its corrosive nature. Manhattan District engineer Colonel Kenneth Nichols placed Major John J. Moran in charge of production at K-25. Production commenced in February 1945, and the first product was shipped to the calutrons in March. By April, the gaseous diffusion plant was producing 1.1 percent product. It was then decided that instead of processing uranium hexafluoride feed from
23240-463: Was dropped back to a steady 2.56 kilograms (5.6 lb) per day enriched to 93.7 percent uranium-235, along with 1.9 percent uranium-234. This was regarded as a satisfactory product by the Los Alamos Laboratory, so on 26 December 1946 enrichment activity at Y-12 was curtailed. The Manhattan Project ended a few days later. Responsibility for the K-25 facility then passed to the newly established Atomic Energy Commission on 1 January 1947. Workers at
23406-572: Was empowered to engage in research and large engineering projects. The NDRC Committee on Uranium became the S-1 Section of the OSRD; the word "uranium" was dropped for security reasons. In July 1941, Briggs proposed spending $ 167,000 on researching uranium, particularly the uranium-235 isotope, and plutonium , which had been isolated for the first time at the University of California in February 1941. In Britain, Frisch and Rudolf Peierls at
23572-418: Was feasible for small objects but impractical for the large diffusers, the tank-like containers that had to hold the gas under pressure. Nickel was a vital war material, and although the Manhattan Project could use its overriding priority to acquire it, making the diffusers out of solid nickel would deplete the national supply. The director of the Manhattan Project, Brigadier General Leslie R. Groves Jr. , gave
23738-537: Was for building and operating the plants that produced the fissile material . Research and production took place at more than 30 sites across the US, the UK, and Canada. The project resulted in two types of atomic bombs, developed concurrently during the war: a relatively simple gun-type fission weapon and a more complex implosion-type nuclear weapon . The Thin Man gun-type design proved impractical to use with plutonium , so
23904-562: Was ideal. Patterson approved the acquisition of the site on 25 November 1942, authorizing $ 440,000 for the purchase of pre-calculated 54,000 acres (22,000 ha), all but 8,900 acres (3,600 ha) of which were already owned by the Federal Government. Secretary of Agriculture Claude R. Wickard granted about 45,000 acres (18,000 ha) of United States Forest Service land to the War Department "for so long as
24070-606: Was just a few blocks from the campus. Major Benjamin K. Hough Jr. was the Manhattan District's Columbia Area engineer, and he moved his offices there too. Kellex was in the Woolworth Building at 233 Broadway in Lower Manhattan . In January 1943, Lieutenant Colonel James C. Stowers was appointed New York Area Engineer, with responsibility for the entire K-25 Project. His small staff, initially of 20 military and civilian personnel but which gradually grew to over 70,
24236-424: Was mainly a reaction with the far more abundant uranium-238 isotope. The former makes up just 0.714 percent of the uranium atoms in natural uranium , about one in every 140; natural uranium is 99.28 percent uranium-238. There is also a tiny amount of uranium-234 , which accounts for just 0.006 percent. At Columbia, John R. Dunning believed this was the case, but Fermi was not so sure. The only way to settle this
24402-418: Was never found but was considered more likely to be a disgruntled employee than an Axis spy. Electric power in the United States was generated at 60 hertz; the power house was able to generate variable frequencies between 45 and 60 hertz, and constant frequencies of 60 and 120 hertz. This capability was not ultimately required, and all but one of the K-25 systems ran on a constant 60 hertz, the exception using
24568-467: Was not taking advantage of the latest techniques, and they began their own development efforts. Both Bell and Bound Brook sent samples of their powdered nickel barriers to Taylor for evaluation, but he was unimpressed; neither had come up with a practical barrier. At Kellogg's laboratory in Jersey City, New Jersey , Clarence A. Johnson, who was aware of the steps taken by the SAM Laboratories to improve
24734-443: Was put aside to concentrate on producing fission bombs. Teller raised the speculative possibility that an atomic bomb might "ignite" the atmosphere because of a hypothetical fusion reaction of nitrogen nuclei. Bethe calculated that it was "extremely unlikely". A postwar report co-authored by Teller concluded that "whatever the temperature to which a section of the atmosphere may be heated, no self-propagating chain of nuclear reactions
24900-411: Was put to Groves at a meeting on 3 November 1943, and he decided to pursue development of both the Johnson and the Norris-Adler barriers. Groves summoned British help, in the form of Wallace Akers and fifteen members of the British gaseous diffusion project, who reviewed the progress made thus far. Their verdict was that while the new barrier was potentially superior, Keith's undertaking to build
25066-408: Was reluctant to share its technological lead and help the United States develop its own atomic bomb. But the British, who had made significant advances in research early in the war, did not have the resources to carry through such a research program into development while a large portion of their economy was engaged in fighting the war; Tube Alloys soon fell behind its American counterpart. The roles of
25232-473: Was renamed the Oak Ridge Gaseous Diffusion Plant in 1955. Manhattan Project The Manhattan Project was a research and development program undertaken during World War II to produce the first nuclear weapons . It was led by the United States in collaboration with the United Kingdom and Canada. From 1942 to 1946, the project was directed by Major General Leslie Groves of the U.S. Army Corps of Engineers . Nuclear physicist J. Robert Oppenheimer
25398-421: Was required. He spoke to Harvey Bundy and Generals Marshall, Somervell, and Styer about his concerns, advocating that the project be placed under a senior policy committee, with a prestigious officer, preferably Styer, as director. Somervell and Styer selected Groves for the post; General Marshall ordered that he be promoted to brigadier general, as it was felt that the title "general" would hold more sway with
25564-444: Was revised in August 1944 to 0.9 percent by 1 January 1945; 5 percent by 10 June; 15 percent by 1 August; 23 percent by 13 September; and 36 percent as soon as possible after that. A meeting between the Manhattan District and Kellogg on 12 December 1942 recommended the K-25 plant be operated by Union Carbide. This would be through a wholly-owned subsidiary, Carbon and Carbide Chemicals. A cost-plus-fixed-fee contract
25730-411: Was signed on 18 January 1943, setting the fee at $ 75,000 per month. This was later increased to $ 96,000 per month to operate both K-25 and K-27. Union Carbide did not wish to be the sole operator of the facility; Union Carbide suggested the conditioning plant be built and operated by Ford, Bacon & Davis. The Manhattan District found this acceptable, and a cost-plus-fixed-fee contract was negotiated with
25896-442: Was still going on. Cranes started lifting the steel frames into place on 19 January 1944. Kellex's design for the main process building of K-25 called for a four-story U-shaped structure 0.5 miles (0.80 km) long containing 51 main process buildings and three purge cascade buildings. These were divided into nine sections. Within these were cells of six stages. The cells could be operated independently or consecutively within
26062-704: Was the director of the Los Alamos Laboratory that designed the bombs. The Army program was designated the Manhattan District , as its first headquarters were in Manhattan ; the name gradually superseded the official codename, Development of Substitute Materials , for the entire project. The project absorbed its earlier British counterpart, Tube Alloys , and subsumed the program from the American civilian Office of Scientific Research and Development . The Manhattan Project employed nearly 130,000 people at its peak and cost nearly US$ 2 billion (equivalent to about $ 27 billion in 2023), over 80 percent of which
26228-406: Was the largest group, and it was working on the most challenging problem: the design of a suitable barrier through which the gas could diffuse. Another 30 scientists and technicians were working in five other groups. Henry A. Boorse was responsible for the pumps; Booth for the cascade test units. Libby handled chemistry, Nier analytical work and Hugh C. Paxton, engineering support. The Army reorganized
26394-467: Was the resident engineer from Kellex, and Edwin L. Jones, the General Manager of J. A. Jones. Construction began before completion of the design for the gaseous diffusion process. Because of the large amount of electric power the K-25 plant was expected to consume, it was decided to provide it with its own electric power plant. While the Tennessee Valley Authority (TVA) believed it could supply
26560-417: Was therefore a success; key American physicists were now aware of the potential power of an atomic bomb. On 9 October 1941, President Roosevelt approved the atomic program after he convened a meeting with Vannevar Bush and Vice President Henry A. Wallace . He created a Top Policy Group consisting of himself—although he never attended a meeting—Wallace, Bush, Conant, Secretary of War Henry L. Stimson , and
26726-476: Was to have been a military laboratory with Oppenheimer and other researchers commissioned into the Army, but Robert Bacher and Isidor Rabi balked at the idea and convinced Oppenheimer that other scientists would object. Conant, Groves, and Oppenheimer then devised a compromise whereby the laboratory was operated by the University of California under contract to the War Department. Dorothy McKibbin ran
26892-577: Was to obtain a sample of uranium-235 and test it. He had Alfred O. C. Nier from the University of Minnesota to prepare samples of uranium enriched in uranium-234, 235 and 238 using a mass spectrometer . These were ready in February 1940, and Dunning, Eugene T. Booth and Aristid von Grosse then carried out a series of experiments. They demonstrated that uranium-235 was indeed primarily responsible for fission with slow neutrons, but they were unable to determine precise neutron capture cross sections because their samples were not sufficiently enriched. At
27058-410: Was too close to a major population center (Knoxville) in the unlikely event of a major nuclear accident. Groves recruited DuPont in November 1942 to be the prime contractor for the construction of the plutonium production complex. The President of the company, Walter S. Carpenter Jr. , wanted no profit of any kind; for legal reasons a nominal fee of one dollar was agreed upon. DuPont recommended that
27224-479: Was transferred to district control in March 1946. Work began on the 130-acre (53 ha) main facility area on 20 October 1943. Although the site was generally flat, some 3,500,000 cubic yards (2,700,000 m) of soil and rock had to be excavated from areas up to 46 feet (14 m) high, and six major areas had to be filled , to a maximum depth of 23.5 feet (7.2 m). Normally buildings containing complicated heavy machinery would rest on concrete caissons down to
27390-533: Was used for Chicago Pile 3 , the first reactor using heavy water and natural uranium, which went critical on 15 May 1944. The Chalk River, Ontario , site was established to rehouse the Allied effort at the Montreal Laboratory away from an urban area. A new community was built at Deep River, Ontario , to provide residences and facilities for the team members. The site was chosen for its proximity to
27556-570: Was within an order of magnitude of 10 kilograms (22 lb), which was small enough to be carried by a bomber aircraft of the day. In April 1940, Jesse Beams , Ross Gunn , Fermi, Nier, Merle Tuve and Harold Urey had a meeting at the American Physical Society in Washington, D.C. At the time, the prospect of building an atomic bomb seemed dim, and even creating a chain reaction would likely require enriched uranium. They therefore recommended that research be conducted with
#63936