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Chapter 6: Responding to Social Needs

By the 1970s, after 30 years of steady progress in nuclear reactor design and technology, growing public concern over problems with nuclear waste disposal, the environmental and health effects of radiation, and the possibility of accidents at nuclear power plants had undermined public confidence in both the AEC in particular and nuclear energy in general. These concerns, which shook the nuclear energy industry, led to dramatic changes in leadership within the AEC.

The High Flux Isotope Reactor and facilities for processing transuraniumelements in Melton Valley.
The High Flux Isotope Reactor and facilities for processing transuraniumelements in Melton Valley.

From the early 1960s until the early 1970s, the AEC was led by Chairman Glenn Seaborg, a Nobel laureate chemist associated with the Metallurgical Laboratory in Chicago during World War II. The AEC was led subsequently by an economist and then a marine biologist, before being split into the Energy Research and Development Administration (ERDA) and the Nuclear Regulatory Commission (NRC) in 1974. In addition, the Joint Committee on Atomic Energy, which had directed AEC activities for decades, disbanded. This transition confirmed that the institutional framework, which had served nuclear power well in the years following World War II, would no longer be sufficient to meet the challenges of the future. 

The Laboratory reacted to the dramatic transitions within the AEC with its own critical changes. Although not sundered like the AEC, it expanded its traditional focus on uranium fission to undertake broader missions that encompassed all forms of energy. At the same time, Laboratory leadership passed from the hands of a fission expert to a nuclear fuel reprocessing specialist and, finally, to an expert in fusion energy. 

As more powerful research reactors and accelerators were added during the 1960s, the Laboratory became a premier international center for producing and separating transuranic elements. Researchers studied the structures and properties of transuranic elements and nuclei using accelerated particles that range in mass from protons to curium ions. In support of the AEC reactor program, the Laboratory pursued development of a molten salt reactor and also investigated liquid-metal and gas-cooled reactor technologies. By 1970, in response to the new political realities that the nuclear industry faced, the Laboratory also became a center for exploring the safety, environmental, and waste disposal challenges presented by nuclear energy. 

The Laboratory's advance into new research frontiers was both a response to necessity and a deliberate effort to assume new challenges. Budget shortfalls between 1969 and 1973 shelved plans for new reactors and reduced staff from nearly 5500 in 1968 to fewer than 3800 by 1973. Moreover, wartime veterans, now in their 50s and 60s, began to retire as the Laboratory's 30th anniversary neared in 1973. The departure of Oak Ridge's Manhattan Project engineers and scientists left a void in the institutional culture that was progressively filled by a new generation who brought their own interests and experiences to the research agenda. Having come of age in the 1960s, this new generation carried somewhat different priorities and sensibilities to the workplace than had the original scientists, for whom World War II had served as the defining period in their careers. 

To meet these challenges, Laboratory management reorganized and launched a series of retraining programs designed to transcend the traditional uranium fission focus. These new efforts led to investigations into all forms of energy—a broadening of research that made the Laboratory more responsive to the political and social changes sweeping the nation.

In the aftermath of Earth Day in April 1970 and passage of a series of environmental laws and regulations intended to bring environmental concerns to the forefront of the nation's policy agenda, the public clamored for more "socially relevant" science that would address everyday concerns. In 1973, as Americans lined up to purchase gasoline and turned down their thermostats because of shortages of imported oil, the desire for relevant science was never more urgent. (See related article, Earth Day 1970.)

Laboratory efforts to explore new, non-nuclear energy issues proved both timely and critical. Born at the dawn of the nuclear age and nurtured to maturity during nuclear power's great leap forward in the 1950s, the Laboratory was not about to abandon its ties to nuclear research. Nevertheless, as it experienced and then responded to the dramatic changes of the 1970s, it emerged from this tumultuous decade a multipurpose science research facility, ready to tackle the increasingly complex issues of energy and the environment. (See related article, Nuclear Physics Research: Little Things Mean A Lot.)

SUPER-DUPER COOKER

The high-flux reactor designed under Eugene Wigner's supervision in 1947 and built in Idaho provided the highest neutron flux then available. By the late 1950s, however, the Soviets had designed a reactor that surpassed it. 

"We do not believe the United States can long endure the situation of not having the very best irradiation facilities in the world at its disposal," commented Clark Center, Union Carbide chief at Oak Ridge. "Therefore, we would like to suggest that the Atomic Energy Commission undertake actively a design and development program aimed at the early construction of a very high-flux research reactor." Glenn Seaborg, an expert in transuranic chemistry, concurred with Center and urged the AEC to build a higher-flux reactor.

Lew Keller watches as Chick Wiggins uses a protective glove box at the Transuranic Processing Plant to achieve final purification of the transplutonium elements produced in the High Flux Isotope Reactor.
Lew Keller watches as Chick Wiggins uses a protective glove box at the Transuranic Processing Plant to achieve final purification of the transplutonium elements produced in the High Flux Isotope Reactor.

With these statements of support echoing in Washington, ORNL embarked on the design of what Weinberg labeled a "super-duper cooker." Trapping a reactor neutron flux inside a cylinder encasing water-cooled targets, the proposed High Flux Isotope Reactor would make possible "purely scientific studies of the transuranic elements" and augment the "production of . . . radioisotopes." Weinberg also insisted that the reactor be built with beam ports to provide access for experiments. 

Charles Winters, Alfred Boch, Tom Cole, Richard Cheverton, and George Adamson led the design, engineering, and metallurgical teams for this 100-megawatt (MW) reactor, completed in 1965 as the centerpiece of the Laboratory's new transuranium facilities. Seaborg, having been appointed AEC chairman by President Kennedy, returned to the Laboratory in November 1966 for the dedication. He declared that the exotic experiments made possible by the new High Flux Isotope Reactor would "deepen our comprehension of nature by increasing our understanding of atomic and nuclear structure." (See related article, Structure and Soundness.)

Built in Melton Valley across a ridge from the main X-10 site in Bethel Valley, the High Flux Isotope Reactor irradiated targets to produce elements heavier than uranium at the upper and open end of the periodic table. At the heavily shielded Transuranium Processing Plant adjacent to the reactor, A.L. (Pete) Lotts of the Metals and Ceramics Division led the teams that fabricated targets. Placed in the high neutron flux of the reactor, atoms of the target materials absorbed several neutrons in succession, making their way up the periodic table as they increased in mass and charge. Then, under a program managed by William Burch, the irradiated targets were returned to the processing plant for chemical extraction of the heavy elements berkelium, californium, einsteinium, and fermium. 

The Laboratory distributed the heavy elements to scientists throughout the world and to its own scientists housed in the new Transuranium Research Laboratory. Previously available only in microscopic quantities, the milligrams of heavy elements produced at the High Flux Isotope Reactor proved valuable for research. "Our main effort at ORNL," said Lewin Keller, head of transuranium research, "is directed toward ferreting out their nuclear and chemical properties in order to lay a base for a general understanding of the field." 

Of the transuranic elements, an isotope of element 98 garnered greatest attention. Named for the state where it was discovered, californium-252 fissions spontaneously and is an intense source of neutrons, able to penetrate thick containers and induce fission in uranium-235 and plutonium-239. It could provide short-lived, on-site isotopes in hospitals for immediate use in patients. Cancerous tumors could be treated by implanting californium needles instead of the less effective radium needles used previously. Other transuranic elements afforded practical applications such as tracers for oil well exploration and mineral prospecting. 

Thanks to Weinberg's foresight in demanding beam ports, Wallace Koehler, Mike Wilkinson, Henri Levy, and their associates in the Solid State and Chemistry divisions could use the high-flux reactor's intense neutron beams for materials studies. Of particular significance were materials investigations that focused on the magnetic interactions of neutrons with materials, which helped to explain unusual magnetic properties of rare earth metals, alloys, and compounds. 

The High Flux Isotope Reactor served science, industry, and medicine for more than a quarter century. Although shut down because of vessel embrittlement in November 1986 and subsequently restarted at 85% of its original power, by 1991 it had gone through 300 fuel cycles that provided benefits ranging from advancing knowledge of materials to enhancing understanding of U.S. history. In 1991, neutron activation analysis of hair and nail samples from the grave of President Zachary Taylor indicated he had not been poisoned by arsenic while in office, as one historian suspected. Americans can rest assured knowing that President Taylor died of natural causes—thanks to the Laboratory's High Flux Isotope Reactor and to the analysis made there by Larry Robinson and Frank Dyer, both of the Analytical Chemistry Division.

THE LAST REACTORS

Phantoms for estimating radiation doses in the human body are checked at the Health and Physics Research Reactor.
Phantoms for estimating radiation doses in the human body are checked at the Health Physics Research Reactor.

Between the 1940s and 1960s, new reactor construction was part of the Laboratory's ever-changing landscape. Those built in the 1960s, however, would mark the end of the Laboratory's "bricks and mortar" reactor era. No new reactors would be built during the 1970s and 1980s, a remarkable dry spell given the rapidly changing nature of nuclear research. (See related article, ORNL and Nuclear Criticality Safety: From Standards to Software.)

Before being forced to close its doors on new reactor construction, the Laboratory (in addition to its work on the High Flux Isotope Reactor) completed the Health Physics Research Reactor, experimented with a molten-salt reactor, and conducted research for AEC's liquid-metal fast breeder reactor and for high-temperature gas-cooled reactors that stirred the interest of the private sector. Next to the High Flux Isotope Reactor, the longest-lived Laboratory reactor built during this decade was the Health Physics Research Reactor. 

Known originally as the "fast burst reactor," the Health Physics Research Reactor was installed in the new Dosimetry Applications Research facility in 1962. John Auxier, later director of the Health Physics Division, managed the design and operation of this small, unmoderated, and unshielded reactor. 

Potted plants irradiated at the Health Physics Research Reactor.
Potted plants irradiated at the Health Physics Research Reactor. 

Composed of a uranium-molybdenum alloy and placed in a cylinder 20 centimeters (8 inches) high and 20 centimeters in diameter, its operation required insertion of a rod into the cylinder to release a neutron pulse used for health physics and biochemical research. In particular, the reactor, which remained operational until 1987, provided data that guided radiation instrument development and dosage assessment. During the 1960s, for example, it helped scientists estimate the solar radiation doses to which Apollo astronauts would be subjected. 

By the mid-1960s, light-water reactors had become the option of choice for the commercial nuclear industry. As a result, the AEC suspended work on the Experimental Gas Cooled Reactor in 1966 in Oak Ridge. When Gulf General Atomic Corporation obtained orders for four high-temperature gas-cooled reactors in 1972, however, the AEC renewed its interest in this reactor technology and boosted Laboratory funds for additional research. The program, which has been managed successively by Robert Charpie, Herbert MacPherson, William Manly, Don Trauger, Paul Kasten, and Frank Homan, has focused most recently on passively safe modular designs. 

Laboratory research into the liquid-metal fast breeder reactor, which had been developed at Argonne National Laboratory, expanded during the late 1960s. William Harms coordinated the Laboratory breeder technology program.

Jim Corum examines a prestressed concrete test vessel for an experimental gas-cooled reactor.
Jim Corum examines a prestressed concrete test vessel for an experimental gas-cooled reactor.

His staff simulated the fast breeder's fuel assemblies, using electric heaters, and tested reactor coolant flows and temperatures. A metallurgical team headed by Peter Patriarca evaluated the materials to be used in the fast breeder's heat exchangers and steam generator. Several Laboratory teams lent support to the effort. For example, William Greenstreet and associates devised a structural design assessment technology to ensure the operational integrity of fast breeder components. 

Work on the breeder accelerated in 1972, when the AEC made Oak Ridge the site of the AEC's demonstration Clinch River Breeder Reactor Project. Laboratory efforts continued until Congress canceled the project in the mid-1980s, following more than a decade of political controversy and debate fueled by concerns about plutonium weapons proliferation and the gradual realization that the United States would not need a breeder reactor for at least 20 years because of the low cost and availability of uranium. 

"DARK HORSE" BREEDER

Alvin Weinberg at the control panel of the Molton Salt Reactor Experiment in October 1967 after it had operated 6000 at full power.
Alvin Weinberg at the control panel of the Molton Salt Reactor Experiment in October 1967 after it had operated 6000 at full power. 

"A dark horse in the reactor sweepstakes." That's how Alvin Weinberg once described the Laboratory's Molten Salt Reactor Experiment to Glenn Seaborg. Weinberg explained that if Argonne's fast breeder encountered unexpected scientific difficulties, Oak Ridge's molten-salt thermal breeder could serve as a backup that would help keep the AEC's research efforts on track.

Based on technology developed for the Aircraft Nuclear Propulsion project, an experimental molten-salt reactor was designed and constructed in the same building that had housed the aircraft reactor. Its purpose was to demonstrate key elements needed for a civilian power reactor. Operation of the Molten Salt Reactor Experiment (MSRE) using uranium-235 fuel began in June 1965 under the supervision of Paul Haubenreich. Program directors Herbert MacPherson, Beecher Briggs, and Murray Rosenthal successively supervised efforts to develop a molten-salt breeder reactor. In an uninterrupted six-month run, the MSRE demonstrated the practicality of this exotic breeder concept. Fuel salt was processed at the reactor, and all the uranium-235 was removed.

AEC Chairman Glenn Seaborg operates the controls of the Molten Salt Reactor on October 8, 1968.
AEC Chairman Glenn Seaborg operates the controls of the Molten Salt Reactor on October 8, 1968.

When the fuel was changed to uranium-233 in October 1968, AEC Chairman Seaborg joined Raymond Stoughton, the Laboratory chemist who co-discovered uranium-233, to raise the reactor to full power. "From here," said Rosenthal, "we hope to go on to the construction of a breeder reactor experiment that we believe can be a stepping stone to an almost inexhaustible source of low-cost energy." 

Weinberg and the Laboratory's staff pressed the AEC for approval of a molten-salt breeder pilot plant. They hoped to set up the pilot plant in the same building that had housed the AEC's Experimental Gas Cooled Reactor until that project was suspended in 1966. 

Argonne's fast breeder had the momentum, however, and Congress proved unreceptive to Laboratory requests to fund large-scale development of a molten-salt breeder. Appealing personally to Seaborg, a chemist, Weinberg complained: "Our problem is not that our idea is a poor one—rather it is different from the main line, and has too chemical a flavor to be fully appreciated by non-chemists." 

Raymond Stoughton, a Laboratory chemist, who co-discovered uranium-233.

Raymond Stoughton, a Laboratory chemist, who co-discovered uranium-233.

Meanwhile, the Molten Salt Reactor Experiment operated successfully on uranium-233 fuel from October 1968 until December 1969, when the Laboratory exhausted project funds and placed the reactor on standby. The Laboratory continued molten-salt reactor development, as limited funding allowed, until January 1973, when the AEC Reactor Division abruptly ordered work to end within three weeks. 

In the wake of the energy crisis in late 1973, however, new funding for molten-salt reactor research was found and continued until 1976. A unique Laboratory project, the molten-salt reactor, in Weinberg's opinion, was ORNL's greatest technical achievement. He maintained that the molten-salt reactor was safer than most other reactor types. As late as 1977, an electric utility executive advised President Carter of his company's interest in a commercial demonstration of the molten-salt breeder reactor. The government's preoccupation with the liquid-metal fast-breeder reactor, however, drove Oak Ridge's thermal breeder into obscurity. To Weinberg's chagrin, the "dark horse" reactor never emerged from the pack to lead the nuclear research effort.

ACCELERATORS

Craftsmen B. E. Burdette and W. A. Wilburn and engineer Malcolm Richardson, in foreground, adjust a nozzle-to-sphere test machine for the Liquid Metal Fast Breeder Reactor Program in 1975.
Craftsmen B. E. Burdette and W. A. Wilburn and engineer Malcolm Richardson, in foreground, adjust a nozzle-to-sphere test machine for the Liquid Metal Fast Breeder Reactor Program in 1975.

An evolution similar to the molten-salt breeder program marked the Laboratory's accelerator program of the 1960s. The Laboratory's advanced particle accelerators, an isochronous cyclotron and an electron linear accelerator, moved it to the forefront of the nation's research efforts in accelerator physics. However, competition from other accelerator projects, as well as funding constraints, would stall the program in the early 1970s. 

The Oak Ridge Isochronous Cyclotron (ORIC) began operating in 1963, firing protons, alpha particles, and other light projectiles into various targets to produce heavy ions. Instead of the uniform magnetic fields used in the Laboratory's first cyclotrons, ORIC employed tailored sectors with a varying magnetic field. This design compensated for increases in the mass of ions as they accelerated, both focusing their paths and keeping them in resonance at high energies. In its day, ORIC's design was considered a major technological breakthrough. 

ORIC provided ion beams of nitrogen, oxygen, neon, and argon, making them available for research in physics and chemistry. Built on the east side of the X-10 site in Bethel Valley, the new cyclotron brought Robert Livingston's Electronuclear Division to the Laboratory from the Y-12 Plant. In 1972, the Electronuclear Division consolidated with the Physics Division under the direction first of Joseph Fowler and later of Paul Stelson and James Ball, all of whom reported to Alex Zucker, the associate director for physical sciences.

Original electron injector and linear accelerator of the Oak Ridge Electron Linear Accelerator.
Original electron injector and linear accelerator of the Oak Ridge Electron Linear Accelerator.

A year after ORIC obtained its first heavy-ion beam, the Laboratory completed the Oak Ridge Electron Linear Accelerator (ORELA). Except for an office and laboratory building, this accelerator was underground, covered by 6 meters (20 feet) of earth shielding. Electron bursts traveled 23 meters (75 feet) along the accelerator tube to bombard a water-cooled tantalum target, producing more than 10 times as many neutrons for short pulse operation than any other linear accelerator in the world. From the target room, the neutrons passed through 11 radial flight tubes to underground stations for experiments.

A joint project of the Physics and Neutron Physics divisions, with Jack Harvey and Fred Maienschien as co-directors, ORELA's main purpose was to obtain fast-neutron cross sections for the fast-breeder reactor program-that is, to determine the probability that a given fuel, shielding, or structural material would absorb fast neutrons. It served this purpose admirably, and it still contributes a great deal to fundamental physical science. In 1990, for example, ORELA's intense neutron beams bombarded a lead-208 target, allowing researchers to measure the size of the force holding together the three quarks composing a neutron. This research effort, led by Jack Harvey, Nat Hill, and researchers from the University of Vienna, advanced scientific understanding of the strong force that glues a neutron together. 

Noah Johnson, Dan Horen, and Fred Bertrand viewing an illuminated map of Oak Ridge Isochronous Cyclotron beam lines.
Noah Johnson, Dan Horen, and Fred Bertrand viewing an illuminated map of Oak Ridge Isochronous Cyclotron beam lines.

By the time ORIC and ORELA were fully operational in 1969, the Laboratory had planned to build another machine capable of accelerating heavy ions into an energy range where super-heavy transuranic elements could be investigated. With the support of universities throughout the region, this accelerator began as a southern regional project. In fact, the Laboratory considered naming it CHEROKEE (after one of the Southeast's most noted Native American tribes), but top scientists could not find the words to form an appropriate acronym; so it was named APACHE, the Accelerator for Physics And Chemistry of Heavy Elements. 

Balking at its $25-million cost, President Richard Nixon's budget office rejected the Laboratory's regional APACHE concept in 1969. Discussing the administration's unfavorable decision at AEC headquarters, Alex Zucker learned the budget office and the AEC would consider only national, not regionally sponsored, accelerators. To secure approval for an advanced accelerator, it would be necessary for the Laboratory to explain the unmet challenges of heavy-ion research, show that it served "truly important national needs," and demonstrate that it would protect the United States from being surpassed in scientific research by other nations, particularly the Soviet Union.

Jim Ball (left) and John Pinajian (right) meet Joseph Hamilton of Vanderbilt University at the entrance to the Oak Ridge Isochronous Cyclotron Beam room.
Jim Ball (left) and John Pinajian (right) meet Joseph Hamilton of Vanderbilt University at the entrance to the Oak Ridge Isochronous Cyclotron Beam room.

Asserting that the proposed accelerator would advance understanding of "the behavior of nuclei in close collision and the properties of highly excited, very heavy nuclear aggregates," Zucker recommended that the Laboratory recast its new accelerator project in broader terms, naming it the National Heavy Ion Laboratory. Accepting this counsel, Weinberg established a steering committee headed by Paul Stelson to reformulate the proposal. The committee's efforts were fostered by university physicists who saw value in having the accelerator located in Oak Ridge. 

Led by physicists Joseph Hamilton of Vanderbilt University and William Bugg of the University of Tennessee, a consortium formed in 1968 to unite physicists from 18 universities interested in heavy-ion research at ORIC and the Laboratory's proposed national accelerator. Working with Robert Livingston and Zucker, the consortium obtained combined funding from their universities, state government, and the AEC to finance construction of an addition to the ORIC building. The addition housed the University Isotope Separator of Oak Ridge (UNISOR) that interfaced with beam lines from ORIC. 

Only the Soviet Union had another on-line separator connected to a heavy-ion accelerator. Equally important, this effort represented the first combined funding project for nuclear research hardware in the United States. When the separator facility was completed in 1972, UNISOR's consortium scientists initiated research into new radioisotopes for medical and industrial applications and heavy-nuclei generation in the stars. 

UNISOR and ORIC's ongoing research and widespread academic participation gave the Laboratory proof that its proposed National Heavy Ion Laboratory would serve national needs. Budgetary constraints, however, delayed approval of this new facility until 1974. Named the Holifield Heavy Ion Research Facility after Congressman Chet Holifield, chairman of the Joint Committee on Atomic Energy for many years, this project, under the direction of Jim Ball, became operational in 1980. The new 25-million-volt tandem accelerator, with its tower dominating the landscape, served as the centerpiece of the Laboratory user facilities during the 1980s, attracting scientists from all over the world.

GOLD-PLATED FUSION

Although the Laboratory's proposals for a molten-salt breeder and APACHE accelerator hit fiscal walls in 1969, its fusion energy research continued to receive funding under the stimulus of international competition. In 1969, the AEC authorized the Laboratory to construct a gold-plated fusion machine called ORMAK. 

Inside ORMAK, the Laboratory's first tokamak, which achieved a plasma temperature of 20 million degrees.
Inside ORMAK, the Laboratory's first tokamak, which achieved a plasma temperature of 20 million degrees.

After a wildly optimistic, but essentially unsuccessful, entry into fusion energy research in the 1950s, the world's scientists recognized that better understanding of hydrogen plasma behavior was necessary before any real progress could be made. As a result, fusion scientists settled into the computer trenches during the 1960s hoping to improve the theoretical underpinnings of fusion energy. When it came to fusion, scientists faced a fundamental shortcoming: although confident of their theoretical calculations, they were unsure of how to make it work in practical terms. 

At the Laboratory, attention focused on the electric-field microinstabilities found within the plasma of fusion devices. Empirical experiments continued both with a second Direct Current Experiment and a steady-state fusion device conceived by Raymond Dandl and given the odd name ELMO Bumpy Torus. ELMO's electron cyclotron heating set a record for steady, stable hot-electron plasma. 

Optimism about fusion resurfaced in 1968, when Soviet scientist L.A. Artsimovich of Moscow's Kurchatov Institute announced his doughnut-shaped tokamak had confined a hot plasma. When Artsimovich visited the United States in 1969, Herman Postma, Laboratory chief of fusion research, dispatched a Laboratory team to discuss tokamaks with him.

ELMO Bumpy Torus, built at ORNL for fusion energy experiments, set a record for plasma heating.
ELMO Bumpy Torus, built at ORNL for fusion energy experiments, set a record for plasma heating.

Enthusiastic about what they heard, Postma's team proposed to the AEC construction of a tokamak at the Laboratory. They received quick approval, together with a mandate to have it operational by 1971. While the Oak Ridge tokamak, called ORMAK, brought the Laboratory back into a race with the Soviets, Artsimovich and other Soviets, in the unique cooperative spirit that characterized fusion research even during the Cold War, provided helpful information for ORMAK's design. 

Sometimes working three shifts daily, the Laboratory's thermonuclear staff, with assistance from skilled craftsmen at the Y-12 Plant, rushed ORMAK's construction. The plasma was created inside a doughnut-shaped vacuum chamber (torus) of aluminum with a gold-plated liner. Coils of electrical conductors cooled by liquid nitrogen provided the magnetic field. Michael Roberts, ORMAK's project leader, described the assembly of this complicated machine as an unusual exercise like "putting an orange inside an orange inside an orange, all from the outside."

Interior of a salt mine near Lyons, Kansas, a Laboratory test site for storing nuclear wastes.
Interior of a salt mine near Lyons, Kansas, a Laboratory test site for storing nuclear wastes.

In the summer of 1971, ORMAK generated its first plasma and experiments began, with encouraging results achieved by 1973. Herman Postma worried, however, whether the high-speed neutrons generated in the plasma would destroy the fusion reactors. Materials had to be found to make fusion reactor walls that would withstand the particle damage and stresses before the ORMAK or other fusion devices could generate even a glimmer of interest among commercial power producers. 

More optimistic, Weinberg noted that the ORMAK design permitted installation of a larger vacuum chamber ring (torus) that would become ORMAK II. "With great good luck," he forecast, "ORMAK II might tell us that it would be a good gamble to go to a big ORMAK III, which might be the fusion equivalent of the 1942 experiment at Stagg Field in Chicago." Elusive plasma slipped from ORMAK's golden grip, however, and neither ORMAK nor subsequent fusion machines has yet achieved a self-sustaining fusion reaction. 

NUCLEAR ENERGY AND THE ENVIRONMENT

While basic science and experimental reactor as within the Laboratory, political, legal, and popular protests far from the Oak Ridge Reservation contributed mightily toward reorienting its missions after 1969. Although dozens of reactors for commercial power production were then in the planning and construction phases, the nuclear industry remained troubled by three concerns: reactor safety, power-plant environmental impacts, and safe disposal of radioactive wastes. These concerns also challenged the Laboratory. 

After 13 years of study, the Laboratory proposed entombing high-level radioactive wastes in deep salt mines near Lyons, Kansas. In 1970, the AEC provided $25 million to proceed with the salt mine repository. 

Noting that the wastes would be hazardous for thousands of years, Weinberg warned, "We must be as certain as one can possibly be of anything that the waste, once sequestered by the salt, can under no conceivable circumstances come in contact with the biosphere." Laboratory scientists concluded that the salt mines, located in a geologically stable region, would not be affected by earthquakes, migrating groundwater, or continental ice sheets that might reappear during the wastes' long-lived radioactivity. 

Willie Linjinsky and Wayne Taylor examine a tumor induced in a rat by feeding it an amine and a nitrite.
Willie Linjinsky and Wayne Taylor examine a tumor induced in a rat by feeding it an amine and a nitrite.

People living near Lyons supported the Laboratory's salt vault plan, but environmental activists and Kansas state officials opposed use of the salt mines on several grounds. Their concerns extended beyond questions of technical capability to deep-seated worries about sound and effective administration over the long haul. Activists claimed that underground disposal for millennia would require creation of a secular "priesthood" charged with warning people never to drill or disturb the burial grounds. "It is our belief that disposal in salt is essentially foolproof," replied Weinberg, although conceding that a "kind of minimal priesthood will be necessary." 

During intense design studies in 1971, the Laboratory and its consultants found that the many well holes already drilled into the Lyons salt formation in some circumstances might allow groundwater to enter the salt mines, thus raising technical questions about the site's long-term suitability. The salt mine disposal plan also became a heated political issue in Kansas. In 1972, the AEC authorized the Kansas geological commission to search for alternative salt mines in Kansas and directed the Laboratory to study salt formations in other states. For the moment, the AEC announced, radioactive wastes would be solidified and stored in aboveground concrete vaults at the site of their origin. That moment has turned into decades, as scientific and political debates concerning radioactive waste disposal issues continue to this day. They are not likely to be resolved soon. 

In the 1970s, the public became concerned about the health effects of exposure to wastes at the other end of the nuclear fuel cycle—the uranium mine. In 1973 ORNL health physicists Fred Haywood, George Kerr, Phil Perdue, and Bill Fox traveled to Grand Junction, Colorado, to determine the radiation hazards in buildings constructed with or on materials containing uranium mine tailings, which are a source of cancer-causing radon daughter products. In the 1980s, a new office called ORNL West was established in Grand Junction. Managed by Craig Little, this office worked with the Instrumentation and Controls Division to develop a field survey technique using triangulated ultrasound signals and a computer for mapping concentrations of radioactivity to determine where remediation is needed or if it has been effective. 

Because of the Laboratory's research on the health effects of radiation from nuclear energy, including cancer, ORNL played a role in President Nixon's "war on cancer." With additional support, researchers in the Laboratory's Biology Division focused on radiation and chemicals and later viruses and genes, including genes that promote tumors and those that suppress them. Consumer advocates who worried about the safety of hot dogs were especially interested in the findings of ORNL's Willie Lijinsky, who demonstrated that the nitrites widely used as food preservatives react with amines in food and drugs to form cancer-causing nitrosamines during digestion in the stomach. 

Laboratory researchers were well positioned to attack the cancer problem because they had long sought to understand how organisms prevent or recover from the damaging effects of radiation and how to stimulate these self-protective mechanisms. They had discovered that cells can repair radiation-induced damage after radiation exposure ceases and that deficiencies in cellular repair mechanisms can predispose the organism to cancer. 

Public and legal concerns about the environmental effects of nuclear power brought the Laboratory's studies of terrestrial and aquatic habitats to the forefront of its research agenda during the early 1970s. Using the "systems ecology" paradigm pioneered by Jerry Olson, Laboratory ecologists investigated radionuclide transport through the environment. Olson examined the migration of cesium-137 through forest ecosystems by inoculating tulip poplar trees behind the Health Physics Research Reactor with cesium-137, thereby establishing the first such experimental research center for forest ecosystem studies. 

In 1968, the National Science Foundation placed Stan Auerbach in charge of a deciduous forest biome program in which the Laboratory contracted with universities for studies of photosynthesis, transpiration, soil decomposition, and nutrient cycling in forest systems in the eastern United States. That same year, David Reichle led a Laboratory forest research team that initiated large-scale forest ecosystem research. This work was a forerunner of subsequent Laboratory programs that investigated acidic deposition, biomass energy production, and global climatic change. 

Environmental studies at the Laboratory received an unexpected boost in 1971 when a federal court, in a decision on a planned nuclear plant at Calvert Cliffs, Maryland, ordered major revisions of AEC environmental impact statements as an essential part of reactor licensing procedures. Required to complete 92 environmental impact statements by 1972, the AEC asked for help from its Battelle Northwest, Argonne, and Oak Ridge national laboratories. Giving this effort the highest priority, Weinberg declared, "Nuclear energy, in fact any energy, in the United States simply must come to some terms with the environment." 

The Laboratory's skeleton staff for environmental impact statements, headed by Edward Struxness and Thomas Row, expanded in 1972 to include about 75 scientists and technicians. Staff working on these reports formed the nucleus of the Energy Division, established in 1974 under Samuel Beall's leadership. (See related article, Environmental Impact Assessments.)

The Calvert Cliffs decision required the AEC to consider the effects of nuclear plant discharges of heated water on the aquatic environment. Chuck Coutant led a Laboratory team assigned the task of developing federal water temperature criteria to protect aquatic life. For these and related studies, the Laboratory initiated construction of an Aquatic Ecology Laboratory, completed in 1973. Only the Pacific Northwest Laboratory had a similar laboratory. Its initial equipment consisted of 20 water tanks, each containing various fish species, and a computer controlled heated-water system to supply water of proper temperature to the tanks; outside were six ponds for breeding fish and conducting field experiments. Early experiments at the aquatics laboratory investigated the survival rate of fish and fish eggs at elevated temperatures. (See related article, Y Not Swans.)

Gordon Blaylock and Neal Griffin collect fish in 1968 from White Oak Lake to study the effects of low-level radiation on fish reproduction.
Gordon Blaylock and Neal Griffin collect fish in 1968 from White Oak Lake to study the effects of low-level radiation on fish reproduction.

To determine the water temperature preferences of fish in streams, Coutant and Jim Rochelle of the Instrumentation and Controls Division developed a temperature-sensitive ultrasonic fish tag. The "electronic thermometer," which can be surgically implanted into a fish, transmits temperature information as high-pitched sound waves of varying frequencies to a hydrophone in a boat or on shore. It has been used by private utilities and government agencies for fish studies. 

An indirect result of the aquatic studies came during licensing hearings for Consolidated Edison's Indian Point-2 nuclear plant on the Hudson River, just north of New York City. Because the Environmental Sciences Division (following recommendations by environmental groups) identified Indian Point as a spawning ground for striped bass, the impact statement for Indian Point-2 called for closed-cycle cooling towers to protect aquatic life from the adverse effects of thermal degradation. Thus, cooling towers, which now serve as the towering symbol of nuclear power plants, were built at Indian Point. 

The legal battle that led to the Indian Point decision took 10 years to complete. During this litigation, Laboratory staff provided technical information to all participants—environmental groups, utility company officials, the Environmental Protection Agency, and other state and federal agencies. 

The high cost of environmental mitigation, reflected both in lengthy courtroom dramas and construction of elaborate cooling systems, concerned many nuclear power advocates. They were troubled as well by stringent reactor safety standards that the Laboratory staff proposed in 1970. Under the direction of Meyer Bender of General Engineering Division, the Laboratory had recommended nearly 100 interim safety standards. Many of these standards were based on investigations by the Heavy Section Steel Technology Program conducted in the Reactor and Metals and Ceramics divisions. Other standards relating to reactor controls were developed by the Instrumentation and Controls Division. 

William Unger and his associates, for example, designed and tested shipping containers for radioactive materials to determine the design that could best withstand collisions during transport. Richard Lyon and Graydon Whitman assessed the ability of reactors to withstand earthquakes, joining with soil engineers who simulated mini-earthquakes by detonating dynamite near the abandoned Experimental Gas Cooled Reactor. George Parker's team studied fission product releases from molten fuels, and Philip Rittenhouse's team investigated the failure of engineered safeguards, particularly the effects of interruptions in water flow to reactors.

EMERGENCY CORE COOLING HEARINGS

"We find ourselves increasingly at those critical intersections of technology and society which underlie some of our country's primary social concerns," Weinberg declared in 1972. He also noted that Laboratory veterans longed for the days when "what we did at ORNL was separate plutonium, measure cross sections, and develop instruments for detecting radiation." Those days were part of the Laboratory's history and were overshadowed in the heated climate of political discourse and public opinion that emerged during the Emergency Core Cooling Systems (ECCS) hearings in 1972. (See related article, The ECCS Hearings.)

The AEC Hearings on Acceptance Criteria for Emergency Core Cooling Systems for Light-Water Cooled Nuclear Power Reactors, or the ECCS hearings for short, proved a critical event, one that forced the Laboratory to face the harsh realities of the new nuclear era of controversy, conflict, and compromise. 

In 1971, President Nixon appointed James Schlesinger, an economist from his budget office, to succeed Glenn Seaborg as AEC chairman. Schlesinger aimed to convert the AEC from an agency that unabashedly promoted nuclear power to one that served as an unbiased "referee." When protest greeted the AEC's interim criteria for emergency core-cooling systems, he convened a quasi-legal hearing for comments from reactor manufacturers, electric utility officials, nuclear scientists, environmentalists, and the public. The hearing began in Bethesda, Maryland, in January 1972 and would continue the entire year. 

To present their views, environmental groups hired attorneys and scientific consultants, who joined attorneys for reactor manufacturers, utilities, and the government to pack the ECCS hearings. Witnesses were subjected to dramatic cross-examinations—a new experience for most scientists, who were accustomed to establishing scientific truth through publications subject to sedate peer review, not through raucous adversarial legal proceedings. 

For reactors with less than 400 MW of capacity, containment vessels can confine radioactive fuel melting even in the event of a serious accident, rendering impossible what is popularly known as the China Syndrome. For reactors with more than 400 MW of capacity, containment vessels are important, but no longer sufficient. An elaborate cooling system must also be built to ensure safety. Weinberg thought it unfortunate that some AEC staff members had not been impressed by the seriousness of this requirement until forced to confront it by antinuclear activists. 

Now that the AEC and nuclear industry had been called into account on this issue, Weinberg urged Laboratory staff to offer their expertise fully and without reservation, regardless of whether they agreed with the existing criteria. Schlesinger agreed. Weinberg complained, however, that his staff should have been involved as fully in preparing the criteria as they would be in testifying at the hearings. 

Among Laboratory staff participating in these lengthy, sometimes contentious, sometimes tedious hearings were William Cottrell, Philip Rittenhouse, David Hobson, and George Lawson. They and other witnesses were grilled by attorneys for days. More than 20,000 pages of testimony were taken from scientists and engineers, who often expressed sharp dissent on technical matters concerning the adequacy of the safety program. Laboratory experts generally considered that existing criteria for reactor safety were based on inadequate research.

In 1977 Carolyn Young studied effects of warm effluents from Bull Run Steam Plant on Melton Hill Lake milfoil.
In 1977 Carolyn Young studied effects of warm effluents from Bull Run Steam Plant on Melton Hill Lake milfoil.

As a result of these showdown hearings, in 1973 the AEC tightened its reactor safety requirements to reduce the chances that reactor cores would overheat as a result of a loss of emergency cooling water. This measure, however, failed to placate critics who preferred a moratorium on nuclear reactor construction. 

The Laboratory's emphasis on reactor safety and environmental protection made it and Director Weinberg unpopular among some nuclear power advocates and members of the AEC staff—a strange turn of events for Laboratory scientists who had devoted their careers to inventing and advancing practical applications of nuclear energy. Opponents of nuclear power, on the other hand, enjoyed quoting Weinberg's chilling declaration: 

Nuclear people have made a Faustian contract with society; we offer an almost unique possibility for a technologically abundant world for the oncoming billions, through our miraculous, inexhaustible energy source; but this energy source at the same time is tainted with potential side effects that, if uncontrolled, could spell disaster. 

Although other events and considerations also played a part, the ECCS hearings of 1972 no doubt influenced major management shifts in 1973 at the Laboratory and AEC. More fundamentally, they influenced the federal government's subsequent decision to dissolve the AEC and to place its regulatory responsibilities and research- and development-related activities into two separate entities. These changes would mark the most profound transition in energy research and development since 1946.

ENERGY TRANSITION

Another crisis—not in public confidence but in energy supplies—threatened the nation during the early 1970s. To meet this challenge, Weinberg sought to reorient and broaden the Laboratory's mission. He was encouraged both by the National Science Foundation (NSF) and the AEC, which in 1971 received congressional approval to investigate energy sources other than nuclear fission. At AEC headquarters, James Bresee, who had headed the Laboratory's civil defense studies, became head of a general energy department, which managed funding for Oak Ridge's innovative energy studies. 

When Congress authorized the AEC in 1971 to investigate all energy sources, Weinberg appointed Sheldon Datz and Mike Wilkinson as heads of a committee to review opportunities for non-nuclear energy research. In addition, he made Robert Livingston the head of an energy council assigned the task of considering new Laboratory missions. 

At the AEC, James Bresee reviewed Laboratory proposals for broad energy research. Among these were studies of improved turbine efficiency, alternative heat disposal methods at power plants, coal gasification, high-temperature batteries, and synthetic fuels made from coal and shale to supplement petroleum and natural gas. 

As these innovative energy studies began, Weinberg also moved the Laboratory into broader environmental programs. He brought David Rose from the Massachusetts Institute of Technology to the Laboratory to manage multidisciplinary research on broad societal problems. The study teams for these innovative research efforts, which Rose hoped would tackle national issues, included such "young turks" as Herman Postma, Bill Fulkerson, and Jack Gibbons. 

James Liverman and Pete Craven drew up a proposal to the National Science Foundation to fund environmental studies at the Laboratory. With support from Congressman Joe Evins, Weinberg and Rose took this proposal to the NSF and received funding from the NSF Research Applied to National Needs (RANN) program for a 1970 summer study. Using regional modeling, social indicators, and system analysis, Rose and his team examined national environmental challenges, such as renewable energy resources. 

Bill 
            Fulkerson--Energy and Environmental Technologies
Bill Fulkerson— Energy and Environmental Technologies

This first attempt at the Laboratory to look at national problems holistically evolved during late 1970 into the NSF Environmental Program managed by Jack Gibbons. Out of this program a few years later came the Laboratory's Conservation and Renewable Energy program, which by 1993 had become the Laboratory's largest energy activity. 

When the NSF first announced its RANN program, Weinberg advised NSF director William McElroy that the Laboratory had "rather miraculously" identified many national needs for research that it could conduct. A poll of Laboratory staff produced 150 new energy and environmental research proposals, a few of which were approved by the NSF. 

Noting that many environmental problems arose as a result of increasing energy use, Roger Carlsmith, Eric Hirst, and their associates initiated studies that examined ways to reduce energy demand by promoting energy conservation. In 1970, they emphasized the importance of better home insulation in substantially cutting energy use for home heating. Moreover, they concluded that increasing the efficiency of transportation and home appliances could significantly lower levels of energy consumption. For design of more efficient central power stations, the Laboratory investigated improved turbine cycles, cryogenic power transmission lines, and "power parks" to cluster power stations outside of urban areas. 

Interest in solar energy flared in 1971, when solar energy advocate Aden Meinel visited the Laboratory and proposed using solar energy to heat liquid sodium and molten salts for large-scale generation of electricity. Murray Rosenthal, who managed the Laboratory's Molten Salt Reactor Program, led a group that assessed the economics of using energy from the sun to produce electricity. 

Although the group concluded that solar power generation would cost more than nuclear or fossil fuel power, Rosenthal recommended additional studies because solar energy could ultimately prove economically attractive if two possible scenarios became a reality: "One is that environmental concerns or other factors could increase coal and nuclear energy costs more than we can foresee; the other is that the collection and conversion of solar energy could become much less costly than we assume." 

With NSF backing, the Laboratory examined solar energy as a potential long-term backup for other energy sources. In addition, David Novelli and Kurt Kraus studied the use of solar heat to enhance biological production of hydrogen and methane fuels as petroleum substitutes. The Laboratory's knowledge of surface physics and semiconductors eventually led to investigations of ways to improve the efficiency of photovoltaic cells by Richard Wood and associates in the Solid State Division as part of the Laboratory's modest solar program.

MANAGEMENT TRANSITION

The Laboratory's 1971 venture into non-nuclear energy research did little to ease its fiscal woes. Successive annual budget reductions in its nuclear energy programs forced corresponding reductions in staff and continuous efforts to lower overhead. As one cost-cutting measure, the Laboratory closed its food service canteens scattered about the complex for employee convenience and replaced them with vending machines. 

Typical of his management style, Weinberg appointed long-range planners to identify supplemental Laboratory missions. Commenting that he felt at times "like a man with a canoe paddle trying to change the course of an ocean liner," David Rose, the Laboratory's first long-range planner, returned to MIT. Robert Livingston succeeded Rose as head of the program planning and analysis group, which included Calvin Burwell and Frank Plasil. Squarely facing the transition in Laboratory missions, this group proposed a staff education program to retrain fission specialists in broader energy and environmental issues. 

Musing on this proposal, Weinberg recognized the dilemma of having experts trained in one field while funding opportunities were becoming more prevalent in other fields. He noted that a similar redirection had marked the experience of Manhattan Project personnel during and after World War II. Wigner, a chemical engineer, switched to nuclear physics. Cosmic ray specialist Ernest Wollan became a health physicist and neutron diffraction expert, and biochemist Kurt Kraus became highly skilled in plutonium chemistry. Weinberg himself had started his career as a biophysicist, only to become a reactor physicist. 

"Enrico Fermi once told me that he made a practice throughout his scientific career of changing fields every five years," Weinberg recalled. He added that, although "there are few Fermis, I think we all easily recognize that the spirit of his advice can well be helpful." 

Lewis Strauss, Glenn Seaborg, Hyman Rickover, Edward Teller, Eugene Wigner, and Chet Holifield celebrate the AEC's 25th anniversary.
Lewis Strauss, Glenn Seaborg, Hyman Rickover, Edward Teller, Eugene Wigner, and Chet Holifield celebrate the AEC's 25th anniversary.

In an effort to enhance internal viability and flexibility, in 1972 the Laboratory initiated a school of environmental effects aimed at producing physical scientists conversant with biology and ecology. This effort stalled, however, because most members of the school were laid off during the massive reduction in force of 1973. Taking cues from his own observations about the Laboratory's future, Weinberg, after a quarter century of service at Oak Ridge, also embarked on a new career. 

The long-time Laboratory director joined Herbert MacPherson and William Baker, president of Bell Laboratories, to form a "think tank" dedicated to coherent long-range energy planning. With support from the AEC and John Sawhill of the Federal Energy Office, they created the Institute for Energy Analysis in late 1973. Oak Ridge Associated Universities served as the institute's contract operator. It opened in January 1974 with Herbert MacPherson as director because Weinberg had been called to Washington to lend his expertise to resolving the national energy crisis. 

Throughout 1973, Floyd Culler served as acting director of the Laboratory. Described as a "muddy boots type," Culler had received acclaim at the fourth Geneva conference on atomic energy in 1971 for objecting to plans by other nations to store liquid nuclear wastes in tanks. He contended that bequeathing radioactive wastes to future generations without providing a permanent, safe disposal system posed serious political and moral questions.(See related article, Floyd Culler: Directed With His Boots On.)

Culler's year as Laboratory director resembled a roller coaster ride, which he later described as a "year of many transitions." In January 1973, Milton Shaw, chief of AEC reactor development programs, mandated a quick end to the Laboratory's molten-salt reactor studies because he was deeply committed to development of the liquid-metal breeder reactor. This decision precipitated what Culler described as the "largest and most painful reduction of employment level at the Laboratory in its history." It also undermined the morale of the nearly 3800 personnel who remained. 

In March 1973, President Nixon appointed Dixy Lee Ray, a marine biologist, as AEC chairman to replace James Schlesinger, who became Secretary of Defense. Ray has been credited with saving the Laboratory from those in the AEC and Congress who were bent on destroying it. 

The highlight of Culler's year was the Laboratory's participation in the national energy strategy. When the president asked Ray to review energy research and recommend an integrated national policy, she called on the national laboratories to assist in undertaking these urgent studies. Murray Rosenthal, who was acting as Culler's deputy director, Jere Nichols, and others spent most of the summer in Washington, providing background information for Ray's report. 

Titled "The Nation's Energy Future," it advocated energy conservation to reduce demand as well as research into new technologies and strategies to increase supplies. The report's ultimate goal was to make the nation energy independent by eliminating its need for imported oil by 1980.

Alvin Weinberg and AEC Chairman Glenn Seaborg in 1967.

The turnaround for Laboratory programs came on the heels of the Israeli-Arab "Yom Kippur War" in the Middle East and the related Arab oil embargo imposed on the United States in October 1973. As disgruntled Americans lined up at filling stations to purchase gasoline, Nixon established the Federal Energy Office. With William Simon as director and John Sawhill as deputy director, the office was responsible for allocating scarce oil and gas supplies during the emergency and for planning long-range solutions to the nation's energy problems. 

At Sawhill's request, Weinberg went to the White House to head the Office of Energy Research and Development. Because Nixon did not appoint a presidential science advisor as had Presidents Eisenhower, Kennedy, and Johnson, Weinberg became science's presence in the White House during the late Nixon and early Ford administrations. 

Floyd Culler noted that the oil embargo and energy crisis made the Laboratory "whole again" by the end of 1973. Reacting to this crisis, Congress pumped new funding into energy research and even approved a modest resumption of molten-salt breeder studies at the Laboratory. "Throughout ORNL's evolution, its central theme has continued to be the development of safe, clean, abundant economic energy systems," Culler said at the end of the year. "The Laboratory is now in a uniquely strong position to undertake a multimodal attack on the nation's energy problems." 

In December 1973, President Nixon proposed a reorganization of the federal energy agencies. As part of this effort, he divided the AEC into two new agencies. AEC responsibilities for energy research and development went to the Energy Research and Development Administration, while AEC regulatory responsibilities were assumed by the Nuclear Regulatory Commission. 

With this new administrative structure in place, Eugene Wigner recommended a Laboratory reorganization paralleling the division of the AEC. He urged that Weinberg be returned to the Laboratory to manage its energy research and development programs and that Culler be assigned responsibility for the Laboratory's safety and environmental programs. "Alvin and Floyd Culler have collaborated for several years," Wigner asserted. "They understand, like, and respect each other." As a result, he said, "conflicts are most unlikely to arise." 

Wigner's recommendation was not accepted. Weinberg served the White House until formation of the Energy Research and Development Administration in late 1974 and then became director of the Institute for Energy Analysis in Oak Ridge. Culler stayed at the Laboratory as deputy director under Herman Postma until 1977, when he became president of the Electric Power Research Institute. 

Life at the Laboratory may have become more tumultuous during the 1970s, but changes in the Laboratory's workplace were no more—or less—than a reflection of dramatic changes in American society. Isolated in the serene hills of East Tennessee, the Laboratory could not avoid being caught in the vortex of a changed energy world. Its future would depend on how well it could respond to the new world "energy" order that suddenly emerged in the aftermath of the Arab oil embargo of 1973 and the ensuing energy crisis. 

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