manufac-turing facilities, and testing grounds in several states.
The facilities built for the Manhattan Project resemble small industrial cities, with hundreds of structures spread over many square miles. Each facility could be treated as a region and would afford an archaeologist a lifetime of research. I focus on Los Alamos National Laboratory and on the Nevada National Security Site (formerly the Nevada Test Site) where assembly, maintenance, and testing of new technologies were carried out; both facilities are today in the Department of Energy. Because the amount of source material is so vast, this case study engages only the Manhattan Project and Project Rover (development of a nuclear-thermal rocket engine).
Despite the secrecy surrounding many projects at Los Alamos and the Nevada National Security Site, historical and archaeological investigations have been ongo-ing in compliance with federal regulations. Although not solvongo-ing research problems originating in archaeology per se , the CRM projects identify, document, and assess the signifi cance of sites and features, bringing to light architecture, facilities, and artifacts of the once-secret US government activities. Moreover, the reports hint that future archaeological research may provide new insights into nuclear-related scien-tifi c projects in these places.
The Manhattan Project
The proliferation of Manhattan Project facilities calls attention to the vast develop-mental distance that separated the prewar discovery of nuclear fi ssion from the fab-rication of functioning weapons. The Manhattan Project is an extreme example of
The US Nuclear Establishment
how a technology project can generate continuous cascades of subsidiary science and technology projects. Before the outbreak of war in Europe, nuclear physics and chemistry were in a rudimentary state and nuclear engineering just a dream, but by the war’s end—with the infusion of at least $1.5 billion in federal dollars and the labor of thousands of investigators—these disciplines had reached an astonishing level of maturity. General information on the Manhattan Project comes from Hoddeson et al. ( 1993 ), Hughes ( 2002 ), and McKay ( 1984 ).
In the late 1930s, physicists in Germany, the United Kingdom, and the USA had forecast that nuclear fi ssion could enable construction of a bomb that, in accord with Einstein’s equation ( E = mc 2 ), would convert a minute amount of matter into an enormous amount of energy. In principle, when a neutron struck the nucleus of an atom of uranium U 235 , it would disintegrate into daughter elements. The fi ssion pro-cess would also eject additional neutrons, causing other uranium atoms to disinte-grate in a continuous “chain reaction” (presuming an initial critical mass of U 235 ).
The fi rst self-sustaining chain reaction, which released thermal energy, radioactive elements, and more neutrons, was achieved by Enrico Fermi’s team at the University of Chicago in December 1942, under the west grandstand of the Alonzo Stagg foot-ball stadium. By using tons of pure graphite as a moderating material (to absorb excess neutrons), they were able to control the reaction. Had their equations been fl awed, a part of Chicago might have vanished under a mushroom cloud.
Fearing that Germany was developing an atom bomb (later proved groundless), the USA embarked on the Manhattan Project with help from the United Kingdom.
The administrative head of the project was General Leslie Groves, an engineer who had supervised construction of the Pentagon; the scientifi c director was J. Robert Oppenheimer, a nuclear physicist at the University of California, Berkeley. They decided to develop two bombs: one based on uranium the other on plutonium.
Uranium occurs naturally in two isotopes, U 238 and U 235 , but only the latter, which makes up but 0.72 % of natural uranium, is fi ssile. A nuclear bomb requires that the percentage of U 235 be increased or “enriched” through isotopic separation. This was the daunting task that the Manhattan Project set for Oak Ridge. The second bomb required fi ssile isotopes of plutonium (Pu 239 and Pu 241 ). Although the transuranic element plutonium occurs naturally in trace amounts (as Pu 244 ), it was fi rst discov-ered in experiments at Berkeley in 1940. Hanford’s task was to produce fi ssile plu-tonium in nuclear reactors (then called “piles”). However, neither Oak Ridge nor Hanford produced appreciable amounts of fi ssile isotopes until well into 1945. (A brief overview of the architecture at the Hanford site is given by Harvey [ 2002 ]).
In the meantime, working with minuscule quantities of enriched uranium and plutonium, Los Alamos investigators determined their chemical and physical prop-erties. This required the design and construction of new apparatus of unprecedented sensitivity to perform measurements that could have been done more easily had suffi cient material been available. A host of other research questions faced the hun-dreds of theorists, chemists, metallurgists, and engineers as they performed calcula-tion after calculacalcula-tion and experiment after experiment on how to achieve critical mass and initiate an uncontrolled chain reaction. For example, initiating a chain reaction at critical mass depended on an infusion of outside neutrons from
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polonium, which in turn could not be achieved until polonium’s properties were known; this required many subsidiary science projects. In addition, to achieve criti-cal mass in the uranium bomb, two subcriticriti-cal masses were projected at each other in a “gun,” the design of which was entirely novel. However, as knowledge of plu-tonium’s properties grew, it became evident that the gun method would not work.
An implosion method was chosen instead, which required an arrangement of shaped charges arrayed around a plutonium sphere or “pit.” To refi ne the design of the implosion detonator, many experiments were carried out with conventional explo-sives—one blast used 100,000 lb of TNT.
At Los Alamos there is a rich historical record of the Manhattan Project build-ings, including photographs and architectural drawings. A recent survey and site evaluation project, whose team contained a historical architect, architect, and con-sulting engineer (McGehee et al. 2003 ), reported the survival of 51 Manhattan Project structures, of which 44 were deemed eligible for inclusion in the National Register of Historic Places. (Several original structures had been damaged by the Cerro Grande fi re of 2000.) These included storage sheds, laboratory and offi ce buildings, fi ring chamber, compressor building, laboratories, cloud chamber build-ing, fi ring pit, shop and dark room, grinding buildbuild-ing, and magazines. In these buildings the fi rst atomic bombs were designed, manufactured, and their compo-nents tested.
The documentation of each structure includes architectural drawings—plans, sections, and elevations—but much of the detail is illegible on pdfs available from Los Alamos National Laboratory. Assuming one can track down original copies, it should be possible to discern activity areas at the time the drawings were made (but many have dates in the 1980s). In addition to the drawings, the report also includes topographic maps on which the structures have been placed and labeled. Because the year of construction is usually known and modifi ca-tions are sometimes documented, we could plot the growth of laboratory facili-ties over time and space, and correlate new construction and alterations with the kinds of scientifi c generalizations being sought and the locational and perfor-mance requirements of the new activities (e.g., proximity to other structures, roads, and environmental features).
Regrettably, historical structures and features have been assessed without appre-ciable archaeological input. Perhaps survey and excavation projects might yield new information about the Manhattan Project. McGehee and Garcia ( 1999 :65) briefl y describe refuse disposal practices, noting that building debris might be tossed over a mesa’s edge. Such debris, which could be found easily today, might yield information on, for example, how effectively materials were used on a project that had an almost unlimited budget, and on other kinds of artifacts that might be mingled with the building debris. Also, test pits judiciously placed around struc-tures might discern undocumented patterns of refuse disposal. Tests for radioactiv-ity would obviously precede archaeological fi eldwork.
Because nuclear physics and chemistry, isotopic separation, and bomb design were on the frontiers of science in the early 1940s, the Manhattan Project became the incubator of new apparatus and new generalizations, exemplifying the cascade
The Manhattan Project
model (Schiffer 2005 )—on steroids. This feature alone invites archaeological scru-tiny, for it should be possible to focus on any subsidiary technology project, such as the design of the uranium gun or the plutonium implosion device. We could learn about the kinds of generalizations being sought, each requiring new apparatus and perhaps new facilities for the anticipated experiments. We could also ferret out dead-end paths and still-born technologies that represented decision nodes leading, perhaps, to a change in a subsidiary project’s direction. The end result would be a model clarifying the interrelationships among the performance requirements of a subsidiary technology, the development of experimental apparatus and facilities, and the creation of new generalizations.
The Manhattan Project established a pattern of large-scale research and develop-ment that would be followed by industrial nations after the war (Hughes 2002 ).
Requiring the collaboration of industrial corporations, university scientists and engineers, and governments, “big science” projects employed a hierarchical organi-zation modeled after large corporations and the military, which integrated people and ostensibly independent institutions. Although having some antecedents, the Manhattan Project was the beginning of the modern “military–industrial–academic complex” that now dominates much science and technology development in the USA, United Kingdom, Germany, Japan, and other nations. An archaeologist might ask: How was the Manhattan project’s organization, with its many subsidiary proj-ects, refl ected in the placement of personnel, activities, and facilities? Did people invent integrative activities that socially mitigated top-down control? If so, what artifacts and places were employed?
The vast source materials available on the Manhattan project, including oral his-tories, autobiographies, critical hishis-tories, and declassifi ed research reports, can be augmented by architectural descriptions and archaeological studies. Together, these lines of evidence would enable us to piece together fascinating stories about the development of science in the context of the twentieth century’s most horrifi cally successful technology project.