I Oak Ridge National Laboratory l W~lfD~

WATER: Current Challenges in Energy Research OakW@:lVU@:W Ridge National Laboratory VOLUME 17 NUMBER FOUR 1984

Acid Rain and Dry Deposition of Atmospheric 2 Pollutants: ORNL Studies the Effects By DAVID SHRINER Acidic precipitation and atmospheric deposition may be involved in the decline of some fm-ests and in the elevation of aluminum levels in streams. ORNL researchers play an important role in pinpointing the effects of atmospheric pollutants on vegetation, fish, and surface waters.

14 Photosynthetic Water Splitting By ELIAS GREENBAUM Using light and algae or nonliving systems, ORNL scientists have photosyntheticaly split water into cxeygen and hydrogen, a clean fuel and chemical feed8tock. COVER CAPTION: The theme of thia iaaue ia water, an important aubject of inveatigation at ORNL partly becauae providing energy for human uae 22 Simulating Processes Within the Earth: Experimental conaumea water and affects ita quality. Geochemistry at ORNL By DAVID COLE The water-energy connection ia Geochemists at ORNL are using unique devices to simulate in a very slwrt time th£ illuatrated in the cover photograph of a chemical processes that form rocks and mineral& The basic research may help solve water wheel (from an abandoned mill) in problems affecting geothermal pqwer, nuclear waste isolation, and exploration for ores and a stream in East Tennessee. (Photograph natural gas. by Bill Clarlt).

33 Drinking Water and Cardiovascular Disease Editor By ELAINE ZEIGHAMI CAROLYN KRAUSE An epidemWlogical study Q{ Wisconsin farmers indicates that persons with cardio!Ja3cular disease drink softer water than persons without the disease. Associate Editor JON JEFFERSON 44 Environmental and Health Impacts of Water Consulting Editor Chlorination By CAROLYN KRAUSE ALEX ZUCKER ORNL chemist Bob Jolley was the first to identify potentially hazardous organic compounds formed by adding chlorine to wastewater. He has also led an effort to identify Design drinking water compounds that cause thyroid disease. BILL CLARK 50 Groundwater Pollution: Environmental and Legal Problems Publication Staff: Technical Editing/Susan A book edited by two ORNL researchers discusses the implications of groundwater Hughes; Typography/Martha Roberson, T. R. pollution caused by human discharges Q{ synthetic chemical'!. ORNL scientists' attempts to Walker; Makeup/Larry Davis; ORNL monitor and prevent deterWrating groundwater quality are explored. Graphic Arts, Photography, and Reproduc­ tion Departments. DEPARTMENTS 1 From the Editor 39 Technical Capsules Water is this issue's tMme. Structure Q{ water studied Iodine hydrolysis and reactors The Review is published quarterly and dis­ 20 Books ORNL has/our J.R 100 winners tributed to employees and others associated E. G. Silver reviews Before It's Too Late: with the Oak Ridge National Laboratory. A Scientist's Case for Nuclear Energy. 56 Awards and Appointments The editorial office is in Building 32 Take a Number 57 Reader's Comment 4500-North, Oak Ridge National Laboratory. P.O. Box X, Oak Ridge, Tennessee 37831. Telephone: Internal 4-7183; commercial (615) OAK RIDGE NATIONAL LABORATORY 574-7183. operated by Martin Marietta Energy Systems, Inc. ISSN 0048-1262 for the Department of Energy FROM THE EDITOR: Water-Its Wonders, Our Worries ~ n J1 ater, the wondrous stuff of life and one of our most precious resources, has long been a compelling ~ subject. For several years we have heard predictions that scarcity of water, or at least a shortage of clean, safe water, will become the crisis of the 1980s, just as the energy crunch was the crisis of the 1970s. The public worries about water pollution and contamination of drinking water-concerns that recently have led to tough legislation. Water remains a vital subject for scientific research. Its properties have been studied and exploited for hundreds of years. At Oak Ridge National Laboratory, where energy is the primary focus of study, water has become an important subject of investigation partly because providing energy for human use consumes water and affects its quality. ORNL scientists have focused on many of water's properties, including its ability to remove, store, and transport heat and to dissolve numerous materials. Its ability to serve as a coolant and neutron moderator in nuclear power reactors led to the development of the concept of light­ water reactors at ORNL and elsewhere. Water in reactors apparently has another benefit: ORNL studies previously reported in the Review and updated in this issue show that because today's reactors are largely water cooled instead of air cooled, they tend to emit significantly less iodine-131 (a hazardous radioactive gas) to the environment following a loss-of-coolant accident such as that at Three Mile Island. In this issue all the articles touch upon water. Eli Greenbaum writes about photosynthetic reactions that can split water into oxygen and hydrogen, which can be a useful chemical feedstock and a clean fuel. Combustion of less clean fuels such as coal can pollute the water that reaches the earth as precipitation. David Shriner writes about evidence that acid rain in combination with particles and gases (such as ozone) deposited from the atmosphere can inhibit the growth of crops and may be responsible for the long-term decline of forests in the eastern United States. He tells us about a plan to manipulate watersheds to determine how acid precipitation is directly or indirectly related to the acidification of streams and the availability of aluminum, which kills fish. Geochemist David Cole tells how an understanding of the properties of hot water and its dissolved minerals underground enables geologists to better explore for geothermal systems, natural gas, and ore deposits, and how geologists can mimic, in a very short time, the chemical processes that form rocks. Epidemiologists and chemists at ORNL are now looking at the issue of drinking water and health. Elaine Zeighami writes about an epidemiological study of Wisconsin farmers that indicates a relationship between use of soft drinking water and increased risk of cardiovascular disease. The study found that hard water, which is high in calcium, appears to lower the risk of death from heart attack and stroke. Most drinking water in the United States is chlorinated to kill disease-causing bacteria. But chlorine can react with organic matter in water to form potentially hazardous organic compounds. An article in this issue discusses the work of ORNL chemist Bob Jolley, who was the first to identify potentially hazardous organic compounds formed by adding chlorine to wastewater. In addition to his research, he has organized five international conferences on the health and environmental impacts of water chlorination. Half of the nation's drinking water comes from groundwater. Unfortunately synthetic organic chemicals from industry and farming have contaminated some groundwater sources of drinking water. A book edited by ORNL researchers Curtis Travis and Elizabeth Etnier and summarized in this issue discusses the environmental and legal problems of groundwater pollution. Two sidebars explore the efforts of ORNL scientists to determine the best sites for monitoring groundwater quality and to divert groundwater from a radioactive waste burial area at ORNL. Basic studies of the structure of water have been carried on at ORNL since the 1940s. X-ray and neutron diffraction studies have allowed researchers to measure the tiny distances between atoms on neighboring molecules of water. The ORNL X-ray data have also been used by radiation physicists elsewhere to obtain enhanced X-ray images for more accurate medical diagnoses. For a laboratory concerned with energy and environmental problems, water will always be a subject of intensive inquiry. Fusion researchers, for example, will be concerned with finding more efficient, economical methods for extracting deuterium from seawater to fuel fusion devices. Basic researchers can drink to the fact that water and the chemical baggage that this excellent solvent carries will continue to be an intellectual challenge for years to come.-Carolyn Krause.

NUMBER FOUR 1984 1 Coal-baming plant in the eaatem United State• epewe eKl(rlr Siclc. an.d dying Norway eprace treee in a Federal Repablic of dio%ide an.d nitrogen. O%idee in.to the atmoephere. Theee gaaee are Germany foreet may be victime of acid rain.. dry atmoepheric the main eon.tribatore of acidity in. rainfall. deposition.. or air pollation.. (Photograph by S. E. Lindberg.) Acid Rain and Dry Deposition of Atmospheric Pollulanls: ORNL studies the Effects

By DAVID SHRINER

~ orne lakes in the western that the common thread accounting acid rain has been an issue in the ~ Adirondack Mountains of for these phenomena is indeed public and political eye. In 1983 the upstate New York no longer pollution of the atmosphere but National Acid Precipitation support trout. Red spruce trees in that the form, pathways, and Assessment Program (NAP AP) forests in Vermont and Tennessee mechanisms of the causal agents reported that acid rain may be are dying. The Statue of Liberty, are much more complex than acid responsible for fishery losses in other monuments, and many stone rain alone. some bodies of water and for a buildings are showing signs of For the past ten years decline in tree growth and survival decay. Is there a common cause? atmospheric deposition of sulfur in some forests in New England Many scientists attribute the cause and nitrogen oxides in the form of and southern Appalachia. Because to acid rain, which is formed in the atmosphere by the interaction of moisture with sulfur dioxide and Acidic precipitation and atmospheric deposition may be involved in the nitrogen oxides emitted primarily decline of some forests and in the elevation of aluminum levels in by the burning of coal, oil, and streams. ORNL researchers play an important role in pinpointing the gasoline. Others, like many effects of atmospheric pollutants on vegetation, fish, and surface waters. environmental scientists at Oak Ridge National Laboratory, believe

2 OAK RIDGE NATIONAL LABORATORY Review derived pollutants on terrestrial ecosystems and has assessed regional-scale environmental problems. In 1979 he was cochairman of the ORNL Life Sciences Symposium. With Chat Richmond and Steve Lindberg of ORNL, he was coeditor of the book Atmospheric Suffur Deposition. He is a member of the Federal Interagency Task Force on Acid Precipitation and is chairman of the National Atmospheric Deposition Program. Here, Shriner checks a plot of soybean plants in an open-topped exposure chamber at ORNL's Air Pollution Effects Field Research Facility. Each chamber has a movable cover to exclude ambient rainfall and an activated charcoal filter to exclude ambient gaseous air pollutants such as ozone. The crops in the chamber can also be exposed to simulated rainfall with different levels of David S. Shriner is ORNL coordinator native of Spokane, Washington, Shriner acidity (pH). By comparing soybean for atmospheric deposition research and also has earned degrees in forest growth in the chamber under controlled leader of the Regional Resource management and plant pathology from conditions with that under ambient Analysis Group of ORNL's the University of Idaho and Pennsylvania conditions, ORNL scientists have Environmental Sciences Division. He State University, respectively. Since determined that ozone, independent of holds a Ph.D. degree in plant pathology coming to ORNL in 1974, he has acid rain, can reduce soybean from North Carolina State University. A studied the fate and effects of energy- productivity by about 10%.

the acid rain problem in the acid rain. A number of scientific aquatic life in streams. And the eastern United States is attributed questions still lack definitive jury is still out on whether acid largely to fossil fuel combustion, answers. For example, no one rain's impact is reversible or legislation was recently proposed in knows whether sulfur emissions irreversible or even all negative. Congress to require a 10-million-ton from coal-fired plants in the What is certain is that these reduction in sulfur dioxide Midwest are chiefly responsible for difficult questions have provided an emissions from coal-fired power the decline of forests in the East or "acid test" of the abilities of some plants. If passed, the measure could the acidification of some lakes in of the nation's best and brightest have raised consumer electric bills the Adirondacks that no longer scientists. to pay for pollution controls on support fish life. Also unclear is During the past ten years, power plants, primarily those in the whether paying the high price of scientists at ORNL have made Midwest that burn high-sulfur coal. emission control would eliminate important contributions toward However, on May 2, 1984, a House the forest and lake acidification understanding the transport, of Representatives subcommittee problems in the East. No one knows deposition, and fate of emissions rejected the acid rain control whether acid rain and dry from human activity, which legislation by a 10 to 9 vote. deposition of sulfuric and nitric ultimately contribute to the acid But as rain does not go away, oxides are the only causes of rain problem. Why has ORNL neither will the volatile issue of change in soils, forests, crops, and become a major center of research

NUMBER FOUR 1984 a Dan Richter collects a soil water sample from Walker Branch Watershed. Dale Johnson hall found that soils differ dramatically in their ability to hold onto sulfur deposited by acid rain and other forms of atmospheric deposition. If sulfate ions move readily through the soil, they may strip away nutrients and ions of hydrogen and aluminum (which can enter streams, where they can be tozic to fish). In other soils, the sulfate ions are bound by iron and aluminum ozides. Johnson and his colleagues are developing models to predict how long different soils can hold onto sulfur and prevent it from removing forest nutrients. activity in the science of atmospheric deposition? For one reason, ORNL has a cadre of interested and committed scientists. Equally important, however, has been the long-term commitment of ORNL's government sponsor (now the Department of Energy) to a quantitative understanding of the fundamental processes regulating In other soils, such as many of forested and aquatic ecosystems One of Johnson's key and of how energy development contributions to understanding the the iron- and aluminum-rich soils of the Southeast, the sulfur might affect them. At ORNL that "big picture"-that is, the regional becomes bound by iron and commitment came first in the form consequences of sulfur deposition aluminum oxides and is retained in of the establishment in 1967 of the by the descent of dry particles, the subsurface soil, partially Walker Branch Watershed in Oak gases, rain, snow, frost, and neutralizing the potential negative Ridge. Today ORNL Walker Branch dew-has been the recognition that effects of sulfur deposition on the studies are providing one of the soils differ dramatically in their forest soil system. Research on nation's longest records of wet and capacity to retain sulfur deposited dry deposition inputs and from the atmosphere. In some soils, Walker Branch and collaboration streamflow outputs from an area of sulfate anions (negatively charged with scientists studying numerous forested landscape. ions) pass readily through the soil other watersheds throughout the and pull away positively charged United States have led Johnson and Watershed Nutrient Dynamics ions (cations) that have been his colleagues to develop models to attached to the negatively charged predict sulfate "breakthrough" in Walker Branch was the site of soil particles. These cations may be these soil systems-that is, to the first watershed-scale sulfur nutrients such as calcium and estimate the finite capacity of the budget (record of sulfur inputs and magnesium or hydrogen ions and soil to hold onto, or adsorb, sulfate outputs) prepared in the United aluminum. If the sulfate anions before beginning to export it and States, a result of efforts in the from acid rain carry away nutrient associated nutrient cations. Also early 1970s by Environmental cations, forest nutrient reserves are significant among their findings Sciences Division (ESD) staff reduced, and tree growth may be has been the fact that forest members-namely, Gray Henderson inhibited. If the sulfate anions ecosystems appear to selectively and then me. Since 1977 ESD's Dale carrying hydrogen ions and conserve limiting nutrient cations Johnson, Dan Richter, and Don aluminum are washed into lakes (vitally needed nutrients in low Todd have refined the earlier work and streams, they may cause supply, such as calcium) while to improve the understanding of acidification of the streams. Even losing nonlimiting cations the processes and mechanisms worse, the introduction of toxic (nutrients in plentiful supply such involved in sulfur movement aluminum to lakes and streams can as sodium, magnesium, and through a forested watershed. kill fish. potassium). Johnson hypothesizes

4 OAK RIDGE NATIONAL LABORATORY Review Mountain stream in the Great Smolt.y Mountains National Parle.. How proceues on land can affect acidification of mountain streama wUl be studied at ORNL and other laboratories in the second luUf of this decade. (Photograph by Ron McConathy.)

supply of forest nutrients and affects forest productivity and (2) to determine if these changes may be related to forest diebacks occurring in some regions of the United States. The base of information generated by our Walker Branch studies has served as a major impetus in the recent development of a proposed $37-million, six-year program of research on the impact of acid rain on forested watersheds. The goal of the research is to determine why some streams and lakes become acidified while others do not. Environmental researchers will propose to assess how the paths that water follows through the watershed and how biological, geological, and chemical interactions on land and within streams and lakes contribute to stream acidification. This proposed DOE program is being spearheaded by Webb Van Winkle and Robb Turner of ORNL in conjunction with staff members of three sister DOE laboratories-Argonne, Brookhaven, and Pacific Northwest. The program, whose final approval that calcium-poor sites do not lose regulating the effects of is still pending, will involve calcium, because the amount atmospheric deposition on forest additions of simulated acid rain and snow to four watersheds, one deposited from the atmosphere element cycling. In collaboration each in the Northeast, Southeast, apparently equals the amount with scientists from four Midwest, and West, beginning in removed by leaching. universities, the National Park late 1985. A newly funded $7.7-million Service, and the U.S. Forest project for the Electric Power Service, they will examine processes Research Institute (EPRI) focuses regulating the movement of sulfate, Air Pollution and Forest Growth on the effects of atmospheric nitrate, hydrogen ions, base cations, In 1982 a large national project deposition on the forest canopy and and aluminum through the forest to evaluate the potential role of air soil processes and on the canopy and soil systems. They will pollution in forest productivity was accumulation, cycling, and losses of monitor fluxes of these ions and launched under the leadership of key elements in forest ecosystems. artificially alter inputs of some Sandy McLaughlin. Although there Johnson and Steve Lindberg (ESD), elements to the soil. The goals of have been numerous reports of principal investigators for the these studies are (1) to assess how isolated cases of reduced tree project, will study key processes much acid deposition changes the growth believed to be caused by air

NUMBER FOUR 1984 5 Short-Leaf Pine, Cades Cove, Tennessee

Dying spruce trees are found througlwut the Great Smoky Mountai1111. The cause is unknown, but scientists have hypothesized that contributing factors may include acid rain, dry atmospheric deposition, and air pollution. (Piwtograph These three slwrtleaf pine tree cores by S. B. McLaughlin.) (mounted in blocks of wood) slww two-year study are now being (such as sulfur dioxide or ozone). suppressed growth in rings formed during the period 1863-191Z, when the summarized. Nevertheless, this study's Copperhill smelter was operating. The Preliminary findings indicate contribution in guiding the cores came from trees in the Smoky that for some species there has development of future research Mountains that were downwind from the been a marked and synchronous initiatives and in generating copper smelter, which emitted sulfur testable hypotheses regarding the dio%ide. Suppressed growth is also seen decrease in the width of annual in rings formed after 1950, po88ibly d'"' to growth rings formed during the possible causes for the observed air pollution. past 20-25 years. The magnitude of slowdown in forest growth the observed growth changes varies represents a major milestone in between species and with site understanding the regional impacts pollution, only recently has the quality and elevation. Because of air pollutants. information been available to declining growth may be caused by An additional contribution of evaluate regional-scale patterns of natural factors such as tree and the FORAST project has been the forest growth and to examine their stand aging and regional changes in development of techniques for using correlation with various indices of climate, this project is attempting trace element signatures in tree­ atmospheric pollution. This to examine spatial and temporal ring tissues as an index of past air information has been obtained by gradients in a variety of possible pollution in a region. In May 1984 the FORAST (Forest Response to causative factors. Included among ESD's Fred Baes and McLaughlin Anthropogenic Stress) project these factors are regional levels of published a paper in Science designed and implemented by atmospheric pollutants such as detailing the tree-ring record McLaughlin and coworkers sulfur and nitrogen oxides as well coinciding with the operation of the T. J. Blasing, Linda Mann, Ron as ozone. The limitation of the copper smelter in Copperhill, McConathy, and Dan Duvick as well study is that it cannot establish Tennessee, during the opening as collaborators at several eastern causal relationships between the decade of the 20th century. They universities and government decline in forest growth and the hypothesized that tree rings in the laboratories. The results of this specific components of air pollution Great Smoky Mountains National

6 OAK RIDGE NATIONAL LABORATORY Review Park (downwind from the smelter, which released large amounts of sulfur dioxide) might yield a correlation between tree growth rates and changes in the level of trace metals, such as iron and titanium (also released from the smelter), in ring tissues. According to a report in the May 5, 1984, issue of Science News, Baes and McLaughlin's study of annual growth rings from shortleaf pine trees in eastern Tennessee shows "increasing metal concentrations since the 1950s and a possibly related decrease in growth during the 1970s." In their paper the ORNL researchers reported that tree rings formed during the 1863-1912 period, when Landaat satellite imagery of Eaat the Copperhill smelter was in it was difficult to quantify. Since Tenne.. ee. The bare spot at Copperhill shows the effect of logging and srdfur operation, showed suppressed 1976 Steve Lindberg and his dio:¥ide pollution on vegetation in this growth and increased levels of iron coworkers in ESD have played a area. and other metals. leading role in the nation's research efforts to measure the extent to dissolved in acid rain or attached to Forest Canopy Interactions which dry deposition is a source of dry particles. Their innovative Early work on Walker Branch sulfates, nitrates, and trace metals approaches to measuring dry Watershed suggested that the total to forested landscapes. More deposition on both natural and amount of sulfur deposited on tree importantly, they have studied the artificial surfaces have led to leaves and soil by atmospheric role that the forest canopy plays in increasingly better estimates of the particles, gases, and aerosols (dry capturing materials from wet and relative contributions made by wet deposition) was probably large, but dry deposition, such as metals and dry deposition to the total

NUMBER FOUR 1984 7 Studies of the WCilker Branch Waterahed foreat caJWPY led by Stel/8 Lindberg (above) indicate that aa much aa hCilf of the depoaited elements (s~U:h aa suJ(ur) enter the foreat ecoaystem throKgh dry depoaition, that the sKrface area of the forest canopy significantly in(lKences the seaaonCil contribKtion of such depoaition to the watershed, and that the deciduoru trees of the foreat progressively neKtralize acid rain percolating throKgh the forest caJWpy. deposition of sulfur and trace elements on the Walker Branch Watershed. In a paper published in the March 26, 1982, issue of Science, Lindberg, Ralph Turner of ESD, and Robert Harriss of the National Aeronautics and Space Administration reported that as much as half of the deposited elements, such as sulfur and lead, enter the forest ecosystem through dry deposition, and that reactions between rain and deposited zones of the Great Smoky as a part of the NTN and Multi­ particles on foliage can result in Mountains. In his earlier work, he State Atmospheric Pollution from concentrations of toxic metals on found that these high-elevation Power Plants (MAP3S) programs. leaf surfaces far higher than those forests receive nearly 50% of their Quality-assured data from these occurring in rain alone. total moisture and 70% to 80% of networks, which use standardized Bill Hoffman, an Oak Ridge total sulfate and nitrate deposition siting and sampling protocols, form Associated Universities visiting from cloud water. The extremely the basis for evaluating professor working with Lindberg, high deposition rates may make an atmospheric transport models found that the Walker Branch important contribution to the death ultimately needed to establish the forest canopy progressively observed among red spruce trees in relationship between sources of neutralizes acid rain percolating high-elevation forests in Vermont pollution and the deposition of through it. Thus the canopy can and Tennessee. those pollutants at receptor sites of alter the acidity of precipitation ORNL has maintained a charter interest. before it reaches forest soils, membership in the National Acid Rain and Vegetation streams, and lakes. Atmospheric Deposition Program. Possible consequences of these This national network of Some of ORNL's early studies of reactions in the canopy, such as precipitation chemistry monitoring the effects of acidic precipitation on disruption of normal nutrient sites, which currently includes vegetation grew out of my cycling, are now under study by approximately 150 monitoring Laboratory seed money proposal Lindberg and Gary Lovett of ESD. stations across the country, has that was funded in 1975. At that Preliminary indications are that been adopted as the core of a time, ORNL's overall research acidic deposition may increase the National Trends Network (NTN) effort in air pollution effects was in loss of nutrients from foliage by under the sponsorship of the its infancy. The seed money up to 40% above normal leaching NAPAP program. At the investment in a facility to simulate rates. Lovett is also expanding on monitoring site at the Oak Ridge rainfall in Laboratory greenhouses his recently published studies of National Environmental Research was a first step toward receiving cloud water deposition in high­ Park, deposition of a full suite of funds from DOE, the elevation fir forests of New elements by precipitation has been Environmental Protection Agency England by making similar monitored by Jan Coe of ESD both (EPA), and later EPRI to explore measurements in the spruce-fir weekly and during rainfall events the mechanisms of the effect of

8 OAK RIDGE NATIONAL LABORATORY Review Brent Taltemoto, a gradlUJte atudent from Bowling Green State Univeraity, ia uaing a diffuaion porometer to meaaure the extent to which aoybean leaf pore• open KP to exchange gaa with the atmoaphere. Leaf pore• normally open KP to talte in carbon dioxide (COz) for photoayntheaia, the e88ential proce.. for plant growth. They alao permit Kptalte of ozone. However, if expoaed to a high concentration of ozone, leaf pore• tend to

cloae and abaorb le•• C01• Ozone alao photooxidize• chlorophyll pigment, tluul redKcing photoayntheaia. When ozone impain photoayntheaia, the growth and productivity of expoaed plant• are inhibited.

combined effect of acid rain and ozone, soybean _productivity was 10% lower than that of soybeans protected from the pollutants. Soybeans are apparently more sensitive to acid rain than is winter wheat. At high levels of acid rain, we found that winter wheat actually had improved growth, suggesting that the nitrates in the rain had a fertilizing effect. Effects on Aquatic Ecosystems Research at ORNL on the effects of atmospheric deposition on aquatic ecosystems has recently expanded to include a search for the physiological indicators of stress in trout exposed to episodic fluctuations of hydrogen ions in surface waters. This study, also acid rain on vegetation. understanding of the complex funded by the Laboratory seed At the outset, McLaughlin and I mechanisms involved in plant money program, involves recognized that the study of response to pollutant mixtures. collaborative work between individual pollutants such as ozone, Early in 1981 Johnston and I Marshall Adams of ESD and Carl sulfur dioxide, or acid rain in began a field study, the first of its Burtis of the ORNL Chemical isolation from the influence of kind, to decipher the relative Technology Division (CTD). To simultaneously occurring pollutants importance of gaseous pollutants, date, their work has demonstrated would prevent sorting out the such as ozone, and of acid rain in the promising use of blood principal components of air inhibiting the growth of crops, such chemistry as an indicator of the pollution responsible for long-term as winter wheat and soybeans. stress of acid rain on trout. They regional impacts on plant Results to date have demonstrated have found that the blood in fish productivity. Based on that early that acid rain alone has little under acid stress has elevated concept, subsequent research at the negative effect on the crops studied levels of triglycerides and of the Laboratory has focused on but that ozone alone reduces crop isoenzyme SGOT and reduced levels pollutant mixtures. McLaughlin, yield. The combined effect, which is of sodium. Bill Johnston, George Taylor, and equal to that of the two pollutants A ~econd project was recently Richard Norby have played a added together, results in reduced initiated by Jerry Elwood and his leading role in providing a better plant growth. As a result of the coworkers. Their field studies in

NUMBER FOUR 1984 9 TM degree to which acid• in precipitation enter •urface water• u regulated by proce.. e• within vegetation canopie• and •oU.. ·

Che.ter Richmond. ORNL A ..ociate Director for Biomedical and Environmental Science•. repre•ent• ORNL on the national Interagency Ta8k Force on Acid Precipitation.

ORNL Manages, Synthesizes, and Integrates Acid Precipitation Data

fi0. nother area of ORNL research on atmospheric validated, ORNL staff will work with teams of scientists ~ deposition is the synthesis, integration, and throughout the country to analyze spatial patterns of assessment of the results from the broad range of surface water chemistry and their statistical relationship research activities currently under way in the National to landscape characteristics and deposition patterns Acid Precipitation Assessment Program (NAPAP). The potentially responsible for changes in surface water role of this assessment activity is to pull together as chemistry, such as increased acidity and aluminum complete a picture as possible of atmospheric deposition content. patterns and consequences and to provide that technical The NAPAP program is charged with three information to agency policymakers. Dick Olson and Paul congressionally mandated assessments of the present Kanciruk of the ORNL Environmental Sciences Division and future risk to the environment from atmospheric (ESD) and Gloria eaton of the Information Division are deposition. ORNL's roles in answering key questions and helping the program immensely by developing centralized in data integration have led naturally to the Laboratory data repositories for the NAPAP assessment team and taking a lead role in developing methods for integrated by coordinating the exchange of all forms of data on assessment of the acid precipitation issue. For the 1985 emissions, deposition, and natural resources for the assessment, ORNL staff members are involved in a federal government's Interagency Task Force on Acid synthesis of the current impact of acid deposition on Precipitation. aquatic and terrestrial ecosystems. In addition, methods An important example of this centralized data for performing a fully integrated assessment of the costs management responsibility is the role that Kanciruk plays of future levels of atmospheric deposition and the benefits as data administrator for the National Surface Water of alternative control options are being developed by a Survey of the Environmental Protection Agency. During team of scientists drawn from the National Laboratory the fall quarter of 1984, some 2000 lakes in the eastern Consortium (NLC), which is led by ORNL. A mlijor issue United States were sampled for a variety of chemical of this integrated assessment will be the appropriate parameters indicating sensitivity to surface water expression of uncertainty associated with the aggregation acidification. The production of a verified and validated of atmospheric chemistry and transport data, response of data base of surface water chemistry will be receptor systems, and cost-benefrt analyses. ESD's Bob headquartered at ORNL. Once the data have been Gardner and Virginia Dale are developing methods for

10 OAK RIDGE NATIONAL LABORATORY Review both the southern Appalachians and New England characterize the spatial and temporal patterns of water chemistry in acidic streams, with particular emphasis on the chemistry of aluminum in acidified waters. These studies represent the first of their kind to attempt to relate the chemical and biological effects of headwater stream acidification. The relationships between stream chemical parameters, such as pH (level of acidity), alkalinity, calcium, and aluminum, and biological variables, such as fish density and growth rates, are being determined. The results of this research will permit testing of the general hypothesis that the biological responses to

quantitatively expressing the uncertainty associated with various control options likely to be proposed. For example, they and their colleagues will determine the uncertainty associated with computer model calculations that compare the cost of proposed controls to reduce emissions from power plants in the East and Midwest with the benefit of reducing ecological damage from acid rain in the East.

In late 1984 fhe Environmenfal Protection Agency (EPA) sampled aboaf ZOOO lal&es in fhe eaafem United States for acidify and other parameters. To reach the many lal&es fl&af are inacceuible by road and fo l&aafen fhe collection and analysis of samples, EPA aaed helicopters.

NUMBER FOUR 1984 11 Uaing a ayringe, Marahall Adama draw• effects of acidity and aluminum on Mary Ann Bogle collect• a water aample blood from a trout. Change• in blood fish in low-calcium waters (surface (rom the Sugar Cove Branch in the chemiatry induced by the fiah'• e:tpoaure Cherokee National Foreat on the Tellico to pulaea of acidity will be determined by waters whose underlying bedrock Plain. The water will be analyzed aa part Carl Burtia with a centrifugal faat contains little limestone, which of a project atudying the effect• on fiah analyzer. Fiah may be e:tpoaed to pulaea normally neutralizes acids in growth and denaity of change• in aurface of acidity during rainatorm and water). water chemiatry auch aa increaaed anowmelt eventa. Preliminary finding• acidity and alaminam content. auggeat that fiah aubjected to acid atreaa Future Opportunities for ORNL have higher than normal level• of triglyceride• and lower than normal During the past year, aided by level• of aodia~n in their blood. discretionary funds from ORNL adding powdered limestone instead Central Management, Richard of by installing expensive scrubbers stream acidification are most Genung and Suman Singh of CTD on coal-fired power plants to pronounced in the headwaters and have begun to evaluate potential restrict sulfur emissions. Research progressively decrease downstream. opportunities for the Laboratory to and development efforts at ORNL Hydrologic events such as contribute innovative technological and elsewhere are exploring options stormflow and snowmelt typically breakthroughs in pollution control that may be more efficient and introduce acidity and aluminum technology. The aim of this economical than FGD technology, into streams as a pulse, particularly technology is to reduce emissions of such as coal cleaning and fluidized­ from sensitive forested watersheds. acidic precipitation precursors such bed-combustion and gasification­ Such pulses may cause considerable as sulfur dioxide and nitric oxide. combined cycles. Several promising acid stress on fish. Flue gas desulfurization (FGD) ideas have surfaced, such as a A third project, involving Van technology (scrubbers) available membrane separation technique Winkle, Jim Breck, and Sigurd now is costly and limited in its and a one-step flue-gas treatment Christensen of ESD and colleagues effectiveness. Some utilities, in fact, process. Further development of the at the University of Wyoming will have argued that mitigation rather most promising of these concepts develop and evaluate fish than control measures might be will be pursued with additional population models that incorporate cheaper; for example, acidified soils discretionary funds during fiscal laboratory data on the combined and waters could be neutralized by year 1985.

12 OAK RIDGE NATIONAL LABORATORY Review In addition, Bob Honea and Dick Atmospheric Turbulence and Arnold Hunley sprays inaecticide on Diffusion Laboratory in Oak Ridge. soybean plants to ward away spider Rush of the Energy Division, in mites and army worms. To preserve the conjunction with Richard Durfee of The unique system developed at experimental crop, the planu are sprayed the Computing and Telecom­ ORNL to simulate rainfall over to prevent disease and inaect infestation munications Division, are exploring field-grown vegetation while and are irrigated during periods of the use of the Laboratory's simultaneously excluding ambient extreme drought. University of Tennessee researchers are using some ORNL plots capability in using Landsat rainfall and ambient gaseous to determine which of 13 different remote-sensing imagery to evaluate pollutants is the first of its kind to varieties of soybeans are particularly whether a link exists between past separate out the relative impact of resistant to damage from acid rain and changes in land use patterns and wet and dry deposition on green which are particularly senaitive to acid changes in surface water chemistry. plants and to permit measurement rain. of the net response to an isolated Conclusion pollution stress. are being developed to permit the Atmospheric deposition research An innovative system for the aggregation of many diverse forms in Oak Ridge has resulted in the measurement of gaseous uptake by of data and models to support the development of innovative methods field-grown vegetation represents a synthesis and analysis of the. for understanding and reducing the major advance in determining the ecological consequences of impacts of acid rain and sources of effect of short-term fluctuations in atmospheric deposition. The dry sulfates. Measurement of dry pollutant concentrations on plant multipurpose, multidisciplinary deposition on forest canopies has response. New, fast-response nature of ORNL, in combination been advanced both by direct instrumentation developed at ORNL with a commitment to excellence in measurement techniques using is permitting staff scientists to research and to answering the surrogate surfaces (for large study changes in fish blood long-term "big picture" questions, particles) and by eddy correlation chemistry as a function of rapid has made the Laboratory a key techniques (for small particles and changes in water chemistry that contributor in tackling the complex gases), which are being developed occur during storm events. problems associated with this by the National Oceanic and Finally, new techniques in important national issue. 1!11 Atmospheric Administration's information management (see box)

NUMBER FOUR 1984 13 Elias Greenbaum is a group leader in from Columbia University and has Greenbaum and, behind him, Mark E. ORNL's Chemical Technology Division. recently been elected a Fellow of the Reeves (left) and James E. Thompson His research responsibilities are American Physical Society. The work in the experimental facility used at physical and chemical problems in research described in this article was ORNL to study photosynthetic water photosynthesis and their application to supported by the Department of Energy, splitting. energy and the environment. He has a the Gas Research Institute, and the Ph.D. degree in experimental physics Solar Energy Research Institute. Here,

Photosynthetic water Splitting By ELIAS GREENBAUM

'fR)hotosynthesis is the biological allowed the development of the lipids, and nucleic acids (the key W process in which visible light animal kingdom as well as modern constituents of living matter) from energy is converted into stored civilization. Photosynthesis is a renewable inorganic resources such chemical energy. This stored self-replicating process that can as water, mineral salts, and energy, in the form of food, synthesize energy-rich biomolecules atmospheric carbon dioxide as the biomass, and fossil fuels, has such as carbohydrates, proteins, sole carbon source. A key reaction

14 OAK RIDGE NATIONAL LABORATORY Review ln. n.ormal plant photosynthesis eMrgy­ rich, carbon-baaed biomoleculea are synthesized from water, carbon. dio:dde, and miMral salta. Sunlight provides the eMrgy to drive the synthesis.

oxygen is produced along with ,.-, protons (H+) and electrons (e-). In normal photosynthesis a second / ' light reaction further elevates the I \ energy level of the electrons so that / X ' they may enter the biosynthetic I \ pathway for the production of I CHLOROPHYLL \ energy-rich carbon-based molecules. The path of inorganic carbon in H20 ~~ \ this process was first elucidated by Nobel laureate Melvin Calvin and IWATERI~~~~) /"" \ his collaborators. In this article, however, I will discuss a novel I ?'.1 .A,.> \ photosynthetic pathway in which the flow of electrons is used to I l~ \ produce molecular hydrogen as the I ENERGETIC INTERMEDIATES' e_nergy-rich photoproduct. In this R~~ I pathway the second light reaction C02 I ($P % § fl is used to reduce protons as follows: (CARBON f~l #~~~~ DIOXIDE)#,,~~ ~ 1? 02 , ~ I (OXYGEN) The overall reaction, therefore, is the photo-induced cleavage of water \ (1'1 J into its elemental constituents: hydrogen and oxygen. This reaction \ ~ I can be carried out in a number of ways. For example, we can use \ ~ I living systems composed of green CHEMICAL .,.,,,~ algae or cyanobacteria or a \ ENERGY I ? nonliving system composed of isolated chloroplasts, ferredoxin, \ I and hydrogenase. (Chloroplasts are the photochemical factories of / photosynthesis. Hydrogenase is the ' ' '..._ .,., / special biocatalyst, or enzyme, that catalyzes the production of molecular hydrogen. Ferredoxin is in this synthesis is one of the most equation: an electron relay that connects intriguing challenges at the frontier electron flow from the chloroplasts of photosynthesis research: water to the hydrogenase.) splitting. Photosynthesis is currently This water-splitting reaction When water is split believed to utilize two light may be summarized by the simple photosynthetically, molecular reactions, reactions that are linked

NUMBER FOUR 1984 15 S"nlight t. ~&aed to drive photoaynthetic reactiona that aplit water info rn&ygen and hydrogen. The a"nlight t. capfl&red by the chlorophyll pigment and funneled BIOLOGICAL SOLAR ENERGY CONVERSION to the reaction center• of photoayntheat.. Oxygen t. prod"ced in the chloroplaata. SUNLIGHT Ferredoxin, a molec"lar ahuttle, franaporta electron. from the chloroplaata to the hydrogenaae, the enzyme that catalyzea the prod"ction of hydrogen. Hydrogen prod"ced in tht. manner t. of intereat beca~&ae it t. aolar energy atored aa a gaaeo~&a fuel. S"ch a fuel can be converted to electricity at high efficiency when deaired by chemically reacting it in a fuel cell. Hydrogen can alao be ~&aed aa a feedatoclt. for chemical• and can be a"batifl&ted for liquid fuela to drive enginea, in, for example, automobile• and jet aircraft. FERREDOXIN

FLOW OF ELECTRONS~ in series by an electron transport chain. The light reaction associated with hydrogen evolution (and carbon dioxide reduction) is called Photosystem I; the light reaction problem as well. As mentioned Joliot and his coworkers at the associated with water splitting and earlier, four electrons have to be Institut de Biologie Physico­ oxygen evolution is called removed from two molecules of Chimique as well as on subsequent Photosystem II. Photosystem I is water to evolve one molecule of collaborative research by himself fairly well understood, but the oxygen. From Einstein's Law of and Joliot at Martin Marietta molecular structure and function of Photochemical Equivalence, we Laboratories. His model is based on Photosystem II remain a know that one photon will eject one the characteristic pattern of oxygen challenging scientific problem, both electron. Therefore, a minimum of yields when photosynthetic from a thermodynamic and a four photons must be absorbed in a preparations are illuminated by chemical-mechanistic point of view. Photosystem II water-splitting brief saturating flashes of light For example, we know from reaction center to evolve a molecule from xenon flash lamps. In his thermodynamic tables that a fairly of oxygen. These four photons eject model Kok postulates that oxygen powerful oxidizing potential (>0.8 V electrons from donor to acceptor evolution consists of a linear with respect to the normal molecules. The positive charges left sequence of photon absorption and hydrogen electrode pH = 7) has to behind on the donor molecules are electron removal. He further be generated to oxidize water to the oxidizing equivalents that postulates that an electron carrier oxygen. In plants and algae, oxidize water (i.e., produce oxygen exists in multiple metastable however, this reaction takes place from water). oxidation-reduction states, with in a molecular architectural The best theoretical model for each photo-induced state being structure that is made up of the mechanism of oxygen evolution more oxidized than its predecessor reduced biomolecules. The actual in photosynthesis is the one by one oxidizing equivalent. water-splitting reaction therefore developed by the late Bessel Kok According to Kok, when four occurs in a specialized and and his coworkers at Martin oxidizing equivalents have protective microenvironment, the Marietta Laboratories. Kok based accumulated, water is split, and structure of which is still unknown, his model on results from oxygen is produced. The electron although strong evidence exists to experiments performed by Pierre carrier simultaneously cycles to its indicate that manganese is an essential cofactor in the water­ splitting reaction. Using light and algae or nonliving systems, ORNL scientists have Oxygen Evolution photosynthetically split water into oxygen and hydrogen, a clean fuel and chemical feedstock. The molecular mechanism of oxygen evolution is a challenging

16 OAK RIDGE NATIONAL LABORATORY Review Marl& Reeve• (left) check. a cuvette that hold• algae, which ~ ez]HMed to light {rom the zenon (kuh lamp up front. Jim Thomp•on check. the power •ource that •upplie• electricity to the lamp. The two re•earcher• hove u.ed th~ apparatu. to mea.ure photo.yntlaetic unit •ize• for hydrogen and ozygen production {rom living algae.

alternated with normal periods of photosynthesis. The simultaneous photoproduction of hydrogen and oxygen represents a severe physiological stress for the organisms. This stress is manifested in two ways: (1) by the quantitative loss of chlorophyll at the end of each interval of irradiation and (2) by the absolute rates of light-driven hydrogen and oxygen production. We have initial position in the "clock" long-term stability and endurance discovered that the physiological sequence. of these organisms during their requirements for the simultaneous Energy conversion by the prolonged periods of simultaneous photoproduction of hydrogen and photochemical machinery of hydrogen and oxygen production. oxygen serve as selection or photosynthesis is analogous to Reeves and I have performed the adaptation pressures for the energy conversion by silicon first experiments that demonstrate survival of algal variants that can photovoltaic cells. The first excited the long-term stability of green better sustain the photoreactions as singlet state of chlorophyll (700 nm, algae as they produce hydrogen and measured by retention of 1.8 eV) corresponds to the band-gap oxygen. We found that using visible chlorophyll in the algal sample at of the semiconductor, and the light irradiation in an oxygen-free the end of each 150-h interval. In biological electron carriers and environment produces algal this instance, the pressures are the biocatalysts provide an external variants with enhanced capabilities anaerobic (an almost oxygen-free) conductive pathway by which the for splitting water and producing atmosphere and irradiation that energy is conserved. One such hydrogen. We have also discovered allow a subpopulation of the algae pathway, the focus of this article, is that certain microscopic green to survive better than the other the simultaneous photoproduction algae are extremely rugged subpopulations. We have also of molecular hydrogen and oxygen. organisms for experiments in demonstrated that significant Photosynthesis research in the biophotolysis. For example, in increases in the integrated yields of Chemical Technology Division of working with the wild-type green hydrogen can be obtained by this Oak Ridge National alga Chlamydomonas reinhardtii, we technique of alternating Laboratory-which I have found that hydrogen and oxygen anaerobiosis and hydrogen performed in collaboration with can be produced simultaneously in production with normal Jonathan Woodward, Mark E. a light-driven reaction for hundreds photosynthetic culturing. For Reeves, Joseph P. Eubanks, and of hours. If these algae are used as example, one strain of James E. Thompson-focuses on the inoculum for algal growth in a Chlamydomonas, after 32 h of the energetics and molecular new culture medium, a second anaerobiosis and irradiation, mechanisms of light energy generation of algae is produced that exhibited a '320% increase in conversion by photosynthesis. can be used in a new round of hydrogen yield in third-cycle cells experiments for hydrogen and over that of first-cycle cells. ORNL's Algae Studies oxygen production. We have In using microalgae for the repeated these types of experiments Nonliving Systems biophotolysis of water, an through five cycles consisting of Another approach to important consideration is the hydrogen and oxygen production photosynthetic water splitting is

NUMBER FOUR 1984 17 40 (o ) ~~- <.:li ~· HYDROGEN ~ ii 30 /. 0 C> --· cc E o~· z I 20 w .!: II <.:l E --- ,,----· 0.:.. ,~-· OXYGEN l5 ~ 10 c:: >J:- 0 £,_ .__-'--__.___.____._____._.__-'--__.____, 0 20 40 60 80 100 Diagram of chloroplaat with ita labeled 2 INCIDENT IRRADIANCE (W·m- ) GENERATION NUMBER componenta. The difference• in the analytical ahapea of the light aaturation The {irat meaaurement• of the light­ curve• of the aimultaneou. Chlorophyll retention verau. generation aaturation curve• of the aimultaneou. photoproduetion of hydrogen and O%ygen number for Chlamydomonas reinhardtii photoaynthetie production of hydrogen may be related to the heterogeneou. 1J7c(+). Theae data demonatrate that and ozygen. The analytical ahapea of the diBfribution of the reaction center• of alternating hydrogen production with light-aaturation curve• of photoayntheaiB photoayntheaiB in the photoaynthetic period• of normal photoayntheaiB iB a contain a conaiderable amount of kinetic membrane•. (Cl97Z by Wadaworth method for aelecfing aubpopulationa of and mechaniBtie information on the PubliBhing Company, Inc.) algae with increaaing durabUity of overall photoproeeBBeB. chlorophyll photopigment. a thermodynamic concept, which limit. Photobiological hydrogen the use of reconstituted in vitro represents the amount of chemical evolution behaves similarly. systems, such as the one composed energy stored in molecular Conversion efficiencies of 2 to 3% of isolated spinach chloroplasts, hydrogen divided by the energy of are observed in the linear, low­ ferredoxin, and hydrogenase. the equivalent solar radiation intensity portion of the light Stabilizing the water-splitting needed to produce the hydrogen. saturation curve. These values reaction center in this extracted Thompson has measured the decrease steadily with higher light nonliving system is a challenging absolute efficiencies of converting intensity because of photosynthetic and important biochemical problem. light energy into hydrogen in saturation, which occurs because Upon extraction from several microalgae using an the rate of excitation of the photosynthetic tissues, the water­ original experimental technique reaction centers exceeds the ability splitting reaction and oxygen that involves entrapping algae on of the biochemical electron evolution are among the first filter paper in a precisely known transport system to process the physiological functions to be lost. circular geometry. These filter excitations (i.e., split water and We have begun to make progress in paper-entrapped algae are then put produce energy-rich molecules). In stabilizing nonliving systems to in a specially constructed chamber principle, however, a strategy could retain these useful functions. Using with a window of optically flat be employed to sustain higher techniques of stabilization and front surface and irradiated in a efficiencies with increasing light immobilization of extracted direction perpendicular to the plane intensity. This strategy, first organelles and enzymes, Woodward of the algae. Oxygen and hydrogen suggested by Kok, would use has performed the first are produced in the interior of the mutant algae with a smaller measurements of the simultaneous algal cells. These gases diffuse from photosynthetic unit size. The photoproduction of hydrogen and the solid-liquid matrix of the algae photosynthetic unit size is the ratio oxygen in an immobilized nonliving into the surrounding gas phase, of the number of light-harvesting system. Because immobilization where they are swept out of the antenna chlorophyll molecules to techniques frequently lead to reaction chamber and into gas­ the specialized chlorophyll reaction greater stability of extracted phase sensors located downstream center at which the primary biological components, we are from the algae. photochemistry of photosynthesis optimistic that greater Photosynthesis is a light­ occurs. Decreasing the number of improvements in yields and dependent process. It is linear with antenna molecules relative to the stability can be made using this light at low intensities but number of reaction centers helps approach. saturates at higher reduce this kinetic imbalance at Another key factor in biological intensities-that is, the rate of higher light intensities. This energy production is net conversion photosynthesis levels off as the strategy is being investigated at efficiency. Conversion efficiency is light intensities exceed a maximum ORNL.

18 OAK RIDGE NATIONAL LABORATORY Review ------·------

Perry EubankB (left) and Jonathan In addition to stability and considerable amount of kinetic and Woodward diacWJB data on the efficiency in photosynthetic water mechanistic information on the biophotolyaill of water. splitting, another factor of interest overall process. Eubanks has is the nature of the algae and the recently performed the first source of water. Working in measurements of the light with current thinking that the collaboration with Robert R. L. saturation curves of the physical separation between the Guillard of the Bigelow Laboratory simultaneous photoproduction of light reactions of photosynthesis is for Ocean Sciences, we have hydrogen and oxygen. The key larger than had previously been discovered species of marine result of these experiments is that thought and that the reactions are microalgae that are capable of the analytical shapes of the partitioned according to the sustained simultaneous hydrogen and oxygen curves are not morphological structure of the photoproduction of hydrogen and the same. That is, the hydrogen photosynthetic membranes. oxygen where seawater serves as curve is not related to the oxygen The key goals of photosynthetic the primary substrate for water curve by a simple factor of 2 as water-splitting research in the splitting. Marine algae are would be expected from the Chemical Technology Division are a particularly appealing from a reaction 2H20 - 2H2 + 0 2. These deeper knowledge and practical point of view because results are intriguing because they understanding of the physics and essentially all of the nutrients for imply a partial uncoupling of the chemistry of the light reactions of culturing the algae already exist in two light reactions of photosynthesis and the application seawater and because the water photosynthesis. The question of of this knowledge to a practical requirements will not compete with coupling and location of the light chemical engineering process for freshwater supplies for direct reactions is another frontier the eventual production of human consumption and research problem in photosynthesis. renewable fuels and chemical agricultural applications. Our results on the simultaneous feedstocks. Through further study Inherent in the light saturation photoproduction of molecular and research, we will surely achieve curve of photosynthesis is a hydrogen and oxygen are consistent these goals. Ill

NUMBER FOUR 1984 19 "For those of us in the nuclear field, this book represents 'preaching to the choir,' but good preaching BOOKS it is nonetheless."

Before I~s Too Late: A Scientis~s Case for the fact that an Oak Ridge study, which the Nuclear Energy, Bernard L Cohen, Plenum Press, "60 Minutes" reporters learned about in interviews with New York (1984). Reviewed by Ernest G. Silver, editor of ORNL researchers, showed that the conditions in the Nuclear Safety. United States were so different that no Kyshtym-type event could possibly occur in this country. Nevertheless, Cohen writes that Nader, "who obviously had no ~ hose of us on the staff at ORNL who remember information on this incident, spouted off about how the 1J. Bernie Cohen (now professor of physics and affair illustrates the great dangers of radioactive director of the Scaife Nuclear Physics Laboratory at the waste." Cohen then goes on to say: University of Pittsburgh) from his days in the I am certain that failure to convey the answer of the scientific Electronuclear (now Physics) Division in the 1950s and studies to this key question [i.e., "Could it happen here?"] was not an who have followed his career of nuclear advocacy in the oversight by the TV crew but a purposeful attempt to conceal that years since will not be surprised that this book is a information from the American public. Instead they gave ... Ralph Nader's implied answer that is scientifically indefensible. There was hard-hitting statement of the pronuclear position. It no other reason to have Nader on the show . .. . His only interest in will also be no surprise to Cohen's ORNL colleagues that the situation was to make politically inspired propaganda, and CBS-TV his arguments are cogent, his scientific foundation solid, offered him this free opportunity to do so. and his knowledge of the nuclear energy field I deplore that sort of rhetoric and wish it had been encyclopedic. softened by letting the facts and arguments speak for The other side of the coin with respect to such a themselves. book of frank advocacy, strongly felt and strongly Having said that, however, let me say also that I expressed, is that it contains many uncompromising loved the book. It is an invaluable reference to almost attacks on those whom Cohen believes to be antinuclear. every aspect of the nuclear debate and should be an These attacks are made not only on the antinukes' indispensable tool for those who engage in it. Not all of arguments and conclusions-refutations that are the book will be easy going for lay readers averse to entirely proper and desirable in such a book-but also graphs and quantitative discussions, but the author does on the motives and intellectual honesty of the "antis" try to make his subject comprehensible to that and especially of the news media. Although I agree with readership and has succeeded at least to the point much of what Cohen says in this regard, I feel it where, with a certain amount of effort and reduces the effectiveness of his work by lowering his perseverance, it may be understood. standards. One example will demonstrate this point. Cohen After an introduction that suggests reasons for discusses a segment of the CBS "60 Minutes" television public unease with radiation (including some program on the Soviet Union's Kyshtym radioactive preliminary swipes against John Gofman, Ernest waste accident. The segment featured comments by Sternglass, and Helen Caldicott-three major betes Zorin Medvedev, a scientist who fled the Soviet Union, noires in his bestiary of antinukes), Cohen deals with and antinuclear activist Ralph Nader. In Cohen's view, the nature of ionizing radiation, explaining what is the CBS selection of material deliberately suppressed known about its dangers compared with other insults to

20 OAK RIDGE NATIONAL LABORATORY Review "Because the public does not agree that the risk of a catastrophic meltdown is low, Cohen discusses why the public perceptions are so distorted and finds that the news media are most at fault."

the body. His discussion of the relative magnitudes of The next major issue COhen covers is the various radiation sources and their risks is excellent. He coupling-by the news media and in the public's treats with special attention the Mancuso study and mind-between production of bomb-grade plutonium other studies that tend to impute a much-higher-than­ and civilian breeder reactors. Not surprisingly, he finds official estimate of the risks of low-level radiation. that the coupling is very weak, that reactor-fuel Next comes a discussion of core meltdowns in which plutonium makes poor explosives, that plutonium would Cohen discusses the Three Mile Island event at length not make an attractive terrorist weapon, and that and examines the magnitude of the risks posed by major therefore the risk of terrorist diversion of breeder­ reactor accidents. He concludes that meltdowns are produced plutonium to hold society hostage is very improbable events (none has happened yet) and that if small. any were to occur, most would have no effect on the Last, Cohen turns to the problem of the economics of public at all; but he concedes that the "average" nuclear energy and its competitors. Although admittedly meltdown might cause "only" 400 fatalities and writing as a nonexpert in this area, Cohen makes a $100 million in off-site property damage. Because the convincing case that much of the recent cost increase is public clearly does not appear to agree with the not intrinsic to nuclear energy and its inherent risks. conclusion that the risk of a catastrophic meltdown is Instead, he attributes rising costs to "regulatory very low, Cohen discusses why the public perceptions ratchetting"-that is, the ever-tighter regulation of are so distorted and again finds, not surprisingly, that nuclear power plants to reduce hypothetical risks ever the news media are most at fault. lower, at rapidly escalating cost per (hypothetical) life Cohen then cogently discusses the nature of risk, saved. Cohen calls this cost problem the "Achilles heel" how it may be quantified, and what consideration of of nuclear power and admits that under present various risks can reveal. Using the readily understood circumstances the ordering of new plants by utilities is concept of loss of life expectancy as a way to compare practically excluded. Nevertheless, his comparison shows different risks results in some very graphic (in both that coal-generated electricity from new plants is senses of the word) comparisons. increasing in cost almost as fast as nuclear electricity. And in his final set of arguments, he demolishes the hope for really cheap and clean solar electricity as a ~ he single issue to which Cohen devotes the most practical alternative. l.1 space is nuclear waste, both high and low level, As I stated at the outset, this book is flawed, at least and the risk it imposes. His treatment includes to my taste, by Cohen's excessively strident attack on pathways of radionuclides from disposal sites to the his opponents; nevertheless, it very clearly presents, in a biosphere and especially to people (I cherish the section manner suitable for intelligent lay persons, the heading "Probability for an atom in the ground to enter scientific factors bearing on the nuclear debate. For a human stomach"); waste transport questions; and, those of us in the nuclear field, this book represents most interesting of all, the "philosophical" issue of how "preaching to the choir," but good preaching it is to weight the far-distant-future impacts of present nonetheless. m activities. In all of it he makes very good sense.

NUMBER FOUR 1984 21 Simulating Processes Within The Earth: Experimental Geochemistry at ORNL

By DAVID COLE

\\ n )lhether viewed globally or on Washington and the discovery of origin, one must understand the ~ a local scale, the earth is a seafloor hot spring vents at 21 o N chemical processes that form rocks dynamic and evolving chemical on the East Pacific Rise have and minerals. However, direct system. The recent volcanic focused attention on this fact. To observation is severely restricted; eruption of Mount St. Helens in appreciate fully the earth and its many of the major chemical

22 OAK RIDGE NATIONAL LABORATORY Review David R. Cole is a geochemist in the raised in Lake George, New York. In State. Before joining the Chemistry ORNL Chemistry Division. He was born 1980 he obtained a Ph.D. degree in Division as a research scientist in July in Cooperstown, New York, and was geochemistry and mineralogy from 1982, Cole was a research geochemist Pennsylvania State University. From with the Earth Science Laboratory of 1977 to 1979 he was a National the University of Utah Research Institute Science Foundation Graduate Fellow in in Salt Lake City, a laboratory the Department of Geosciences at Penn supported by the Department of Energy. During his stay in Utah he helped develop quantitative models of stable isotope and chemical behavior in geothermal and ore deposit systems in the western United States. Since coming to ORNL, Cole has been theoretically evaluating the mechanisms and rates of stable isotope exchange between minerals and aqueous solutions at elevated temperatures and pressures. In addition, he and Ed Drummond have been modeling the transport and depositional mechanisms of metals, such as gold and silver, in geothermal brines. Here, he shows his schematic of a geothermal system with a magma chamber as a heat source. processes and events occur at great geosciences research program in the temperature and pressure of l200°C depths or took place in the Chemistry Division of Oak Ridge and 4000 bars, respectively). prehistoric past. In fact, given National Laboratory for the past These experimental geochemical present technological capabilities six years. The principal objective of studies can be divided into two (drilling depths to about 6.4 km, or the program, which is funded by broad categories, hydrothermal (hot 4 miles), only about 0.3% of the the Division of Engineering, water) and silicate melt (molten volume of the earth is readily Mathematical and Geosciences in rock) geochemistry. In both accessible to sampling or direct the Office of Basic Energy Sciences classifications we are interested in observation. Therefore, an of the Department of Energy, is to volatile components, such as water, understanding of the chemical provide basic geochemical carbon dioxide, and sulfur dioxide, processes operating within the information on high-temperature and their role in the formation of earth is heavily dependent on the processes in aqueous and molten­ crustal rocks over a wide range of ability to simulate, through silicate chemical systems temperatures and pressures. ORNL experimental or theoretical means, responsible for the distribution of hydrothermal geochemical research deep-earth conditions currently of elements in the earth's crust. To emphasizes the role of aqueous inaccessible to study. do this the program conducts fluids in transporting and Analogue studies of simplified experimental studies over ranges of depositing the dissolved minerals geological systems, or experiments temperature, pressure, and that form rocks; this research that model the natural systems, composition appropriate for depths includes studies of mineral have been the focus of the to 20 km (12 miles, with a dissolution and the chemical form and stability (the temperature, pressure, and composition range Geochemists at ORNL are using unique devices to simulate in a very over which they occur) of the dissolved constituents up to 600°C short time the chemical processes that form rocks and minerals. The and 200 MPa (2000 bars). The basic research may help solve problems affecting geothermal power, current experimental work on nuclear waste isolation, and exploration for ores and natural gas. silicate melt systems focuses on the mineral stabilities, mineral growth

NUMBER FOUR 1984 23 Hot apringa and geyaera not only relea~~e heat from the earth bat alao depoait minerala. E%amplea are Echimu Geyaer at Norria Baain (left), the hot aprinp at Firel&ole River (center), and Mammoth Hot Spring• (right), all at Yellowatone National Park. rates, and element distributions over temperatures ranging from 600 to 1400°C and pressures to 500 MPa (5000 bars or 72,500 psi) under controlled partial pressures of oxygen. Together, these generic studies provide insight into problems associated with volcanic processes, mineral resource exploration, enhanced techniques for oil and ore recovery, nuclear waste isolation, geothermal energy, development of ceramic structural materials, and energy transfer in magmatic­ hydrothermal systems. The dissolved species. These solutions dissolve, while others precipitate, following discussion highlights a play an important role in several depending on the chemical form portion of the research conducted in geochemical and technological and concentration of the elements these broad areas. processes, for example, in solution. During mineral hydrothermal formation of mineral dissolution and precipitation, the Hydrothermal Geochemistry deposits, hydrothermal crystal porosities (percentage of void Without realizing it, many of us growth and materials synthesis, space) and permeabilities (ability of perform a simple hydrothermal and high-temperature industrial rock to transmit fluids) of the rocks experiment every day in our electrochemical processes. Hot can change dramatically, as can the kitchens. Each time we put a teapot aqueous solutions and mineral aqueous chemistry. One can easily of water on the burner to boil, we deposition can also corrode and clog conclude that if this phenomenon simulate the physical and chemical pipes, respectively, leading to occurs in geothermal systems or processes in many hot spring inefficient heat transfer in petroleum source rocks, the geysers throughout the world. We geothermal power systems and transport of hot fluids, whether observe a vapor (or steam) plume at reduced operating capacity in water water rich or petroleum rich, is the spout and mineral deposition at desalination systems, boilers, power directly affected. Because geologic the bottom and sides of the pot. plants, and cooling systems of exploration for geothermal systems, Anyone who has been to nuclear reactors. To understand the petroleum, and even ore deposits Yellowstone National Park and complex behavior of various types relies heavily on information seen the vapor plume of the Old of hydrothermal solutions, a large gleaned from fluid chemistry, a Faithful geyser rising from an number of experimental complete understanding of the orifice surrounded by mineral investigations have been carried out properties of aqueous solutions and deposits realizes the similarity of to determine the thermodynamic their effects on minerals is crucial the geyser to boiling water in a properties of pure water and of to the development of sound teapot. aqueous solutions over wide ranges exploration models. Natural hydrothermal solutions of temperature and pressure. Significant contributions to are hot (> l00°C) aqueous fluids Based on previous hydrothermal these areas have been and are ranging from dilute solutions of a rock-water experiments, we know continuing to be made by ORNL single solute in water to complex that during the interaction of rocks researchers in the High systems containing high and aqueous solutions at high Temperature/High Pressure concentrations of more than ten temperature, certain minerals Aqueous Group of the Chemistry

24 OAK RIDGE NATIONAL LABORATORY Review ------

reservoir and then decomposes to carbon dioxide (C02) and methane

(CH4) . This hypothesis would be valid if acetate decomposes at a rate slower than its rate of migration with water from sedimentary basins to reservoir rocks. In an effort to understand the kinetics (rate and mechanism) of the thermal decarboxylation (removal of coo- group) of acetate and the role of catalysis in forming carbon dioxide and methane, Drummond and Don Palmer have conducted a series of hydrothermal experiments to measure the decomposition rates of acetate in the presence of a variety of materials including gold, titanium, stainless steel, silica, magnetite (Fea04) , and montmorillonite (a Division. The pioneering work on to aoooc and 20 MPa; conductance clay mineral). The rates of acetate high-temperature properties of cells for studies up to 800°C and decomposition varied greatly, aqueous solutions by Charlie Baes, 400 MPa (4000 bars); and hydrogen depending on the catalytic Dick Busey, Howard Holmes, Milt electrode emf (electromotive force) substrate. Methane and carbon Lietzke, Bill Marshall, Bob Mesmer, cells to measure pH-dependent dioxide were the predominant and Fred Sweeton has been used mineral solubilities up to aoooc and reaction products of these extensively by geochemists in their 50 MPa. These unique facilities are experiments; however, mass studies of natural systems. The being used to examine acid spectrometric analysis revealed ORNL geochemistry program is, in dissociation, hydrolysis (reaction of that hydrocarbons constitute as fact, an outgrowth of earlier the elements with water) of metal much as 40 mol % of the carbon in experimental work by members of ions, formation of chemical species the reaction p:oducts, depending on this group. Currently, hydrothermal in supercritical aqueous fluids and the catalyst. Gold, titanium, and geochemistry research conducted by chloride brines, solubilities of pure montmorillonite were the least Ed Drummond, Dave Wesolowski, minerals, and formation of methane active catalysts, whereas stainless Marshall, me, and others has by thermal decomposition of steel, silica, and magnetite showed evolved to a substantial program hydrocarbons. The modeling marked catalytic effects. that complements and to some research is centered on examining These results have important degree augments the efforts of the complex high-temperature mechanistic implications for the Aqueous Group. multicomponent fluid-mineral process of natural gas migration The ORNL hydrothermal equilibria, and the rates of stable because acetate is available in geochemistry program is divided isotope exchange between minerals significant quantities and is highly into two categories, experimental and fluids at elevated temperatures. mobile in the waters expelled and modeling. The experimental Origins of Natural Gas. How during compaction of basin effort uses the group's unique natural gas (methane) migrates sediments. The appropriate facilities, including gold-ceU from the deeper source rocks of physical, chemical, and geological pressure vessels capable of studying sedimentary basins to reservoir constraints for acetate migration corrosive systems at temperatures rocks has long been a matter of and decomposition were considered and pressures up to 600°C and speculation. One hypothesis is that and integrated in a computer model 200 MPa (2000 bars), respectively; acetate (CH3Coo- ), a common that couples basin subsidence, titanium reaction vessels for constituent in oil field brines, compaction, and fluid flow measuring mineral solubilities up migrates in solution to the parameters with chemical

NUMBER FOUR 1984 25 constraints dictated by the is fixed by the least soluble mineral experimental kinetic data. This form of that element under the analysis suggests that a significant prevailing physical and chemical geological and chemical "window" conditions. This limiting solubility exists wherein acetate is is a function of temperature, sufficiently stable to survive the pressure, and the concentration of thermal regime (90-130°C) of a other solutes present. sedimentary basin long enough to Supersaturation (concentration in migrate out of the source rocks, and excess of the maximum solubility) yet is sufficiently reactive to is sometimes attained in natural decarboxylate to form a natural gas solutions-usually owing to deposit within the time frame environmental changes taking place imposed by the age of the basin during movement of water- but a sediments (10 million to 100 million supersaturated solution is unstable years). and tends to return to equilibrium, CONVECTING MACiMA In addition to the implications however slowly, by precipitation of for natural gas deposits, these one or more minerals. A detailed SchemGtic model of convective flow in a results indicate that acetate might understanding of the equilibrium hydrothermal ay.tem allowing effect of variationa iR permeability of the region be a mobile precursor for the solubilities of minerals and the OR the flow and allowing aurface components of petroleum and can rates of dissolution and diacharge of the total flow. survive moderate hydrothermal precipitation is required to evaluate temperatures (100-300°C) long quantitatively the transport and A series of potentiometric enough to act as a complexing depositional mechanisms of titrations in the hydrogen electrode agent for metals, thereby important rock-forming elements in cell were carried out to measure promoting the mobility of these natural geothermal solutions and brucite solubility and the commodities in some ore-forming waters encountered in high-level hydrolysis (addition of hydroxides systems. Preliminary experiments nuclear waste repository sites. to the metal ion) of magnesium in at 250°C indicate that significant Changes in porosity and aqueous sodium chloride solutions concentrations of gold and iron permeability caused by mineral in temperatures ranging from occur in solution containing acetate dissolution or precipitation not only 60 to 200°C. The results of the and acetic acid (CH3COOH). affect the transport of hot fluids experiments indicate that the The outcome of these and subsequent heat transfer in formation of negatively charged experiments may influence the geothermal systems but also may species, such as Mg(OH)a-, was strategy of exploring for sediment­ correspond to modifications in the negligible in the experiments and hosted gold deposits such as those channelways along which that the titration data can be found in the Basin and Range radionuclide-bearing waters can explained solely in terms of the physiographic province of the migrate from a nuclear waste Mg2+ and Mg(OH)+ aqueous United States. Currently, the repository to potable groundwater species. The experimental importance of organic matter in aquifers. To better understand solubilities agree remarkably well transporting or localizing gold in these processes, ORNL researchers with earlier estimates made by these environments is not well are conducting mineral solubility Baes and Mesmer on the basis of understood. If organic transport of and cation hydrolysis studies using empirical correlations with gold proves to be a viable process, the Laboratory's unique high­ hydrolysis data from other then the current exploration temperature hydrogen electrode elements. More importantly, these strategy may shift emphasis toward concentration cell. experiments demonstrated for the examining areas where rocks either Recent experiments have first time that mineral solubilities are organic rich or exhibit signs of demonstrated the feasibility of at elevated temperatures can be significant organic matter measuring mineral solubilities in a measured directly by monitoring decomposition. hydrogen electrode cell. This the proton concentration in the technique is being used to measure hydrogen electrode cell. Mineral Solubilities and Cation the solubility of hydrolyzed Using the same apparatus, Hydrolysis. The concentration of magnesium, or brucite [Mg(0Hh1 Wesolowski, Drummond, Mesmer, any given element occurring in an by Drummond, Baes, and Paul and Professor H. Ohmoto of aqueous solution has an upper Brown of the University of Pennsylvania State University limit, or maximum solubility, that Wollongong, Australia. measured the formation constants

26 OAK RIDGE NATIONAL LABORATORY Review ------

Dave Wesolowski (left) and Ed for protonated ("proton added") 10 ppm tungsten as HW04- at all Drummond iMert a Haatelloy pressure mononuclear and polynuclear forms temperatures and (2) that cooling is vessel in. a stain.less steel lwuain.g of aqueous tungstate (WOl-) in less important than a decrease in con.tain.in.g a {urnoce. lMide ia a gold bag. This gold-cell pressure vessel ia uaed sodium chloride solutions. the solution acidity in localizing for metal and min.eral solubility Tungstate concentrations ranged tungsten in the crust. e:¥perimen.ts. from 90 to about 2000 parts per In related studies using the million (ppm), and the temperature conductance apparatus, Marshall; and pH ranges were from 95 to Arvin Quist of ORNL; John Frantz temperature and pressure is the 290°C and from 2 to 8, respectively. of the Geophysical Laboratory, determination of the ionization The experimental data suggest that Carnegie Institution of Washington; constants (equilibrium WOl- and HW04- species account and others, have measured proportionation between the ions for most of the tungsten in natural electrical conductances of chloride and the molecules that are not hydrothermal solutions. These salts (NaCl, KCl, CaCl27 MgCl2), ionized in solution) of the salts and results were combined with existing acids (HCl), and other electrolytes acids. This work has demonstrated solubility data on scheelite (Ca W04, (conducting fluid in which the flow a straight line relation of limiting a calcium-containing mineral found of current is accompanied by equivalent conductance in tungsten ore deposits) to movement of ions) in dilute aqueous (conductance at infinite dilution) to describe the chemical mobility of solution at temperatures up to solution density for all the tungsten in crustal fluids. This 800°C and pressures up to 400 MPa electrolytes studied. work suggests (1) that typical (4000 bars). The primary goal in Constant temperature plots of tungsten ore fluids in equilibrium measuring electrical conductances the logarithm of the ionization with scheelite can carry about in these solutions as a function of constants versus the logarithm of

NUMBER FOUR 1984 solution density also produce (gold, silver, lead, zinc, and high total H2S, and relatively high straight lines for the salts and mercury) and mineralogical pH (>5). Conversely, silver acids. Most importantly, the patterns in surface rocks and concentrations in solution, as simplicity of the observed shallow drill holes. AgC12-, are highest at high ionization behavior of these Our goal is to relate temperature (>250°C}, low total electrolytes at temperatures above quantitatively the chemical and H2S, and low pH ( <5). The two 300°C provides a basis from which mineralogical patterns observed in distinct populations of silver/gold reliable estimates can be made of the surface rocks to physical ratios observed in both geothermal ionization constants in regions of chemical processes occurring at and fossil ore deposit systems can temperature and pressure not easily depth in order to more readily be attributed to these differences in measured by experiment. discriminate between geothermal the transport properties of gold and Combining this knowledge with systems having great energy silver. information on mineral solubilities, potential from those that do not. Under most circumstances, gold one can then quantitatively predict However, fundamental questions and silver concentrations decrease the consequences of fluid-rock still remain unanswered regarding in solution because boiling induces interaction such as the sequence the mechanisms (e.g., boiling, mineralization. In fact, boiling is and amounts of minerals deposited mixing, and cooling) responsible for generally a favorable process for in geothermal systems. Variations transporting (solubilizing) and depositing most minerals, including in fluid chemistry monitored in hot depositing gold, silver, lead, zinc, oxides, native metals, sulfides, springs and shallow wells and mercury, and other trace metals. quartz, and, to a lesser extent, changes in mineralogy are used by Ed Drummond and I are carbonates and sulfates. exploration geologists to target currently examining through Interestingly, systems rich in deep geothermal drill holes. By detailed computer calculations the carbon dioxide, although more integrating the field data with importance of geochemical effective in causing pH changes and computer models using the parameters such as temperature, subseq:uent mineralization, also experimental measurements, salinity, pH, hydrogen sulfide (H~) tend to enlarge the areas over geologists can more accurately and carbon dioxide on trace metal which deposition can occur. The assess the potential of an area for solubilities in geothermal brines. reason for this dispersed deposition geothermal energy. We are also quantifying the role of is that, at higher carbon dioxide boiling and fluid mixing as agents concentrations, the total fluid Transpqrt and Deposition of of metal localization. We singled pressure is also higher; thus a Metals in Geothermal Systems. out boiling because in the majority pressure drop occurs during boiling Many shallow gold-silver ore of high-temperature geothermal over a greater vertical interval, deposits are probably "fossil systems, some of the liquid is resulting in a "smeared out" or equivalents" of high-temperature carried off as steam. The most enlarged mineral depositional zone. geothermal systems like significant effect of boiling on the ORNL research efforts are focused Broadlands, New Zealand, and chemistry of a geothermal solution on examining geothermal and fossil Steamboat Springs, Nevada. The is associated with the exsolution hydrothermal systems for evidence evidence strongly suggests that the (removal from solution) of carbon of this behavior to validate the fossil and active systems are dioxide and hydrogen sulfide. chemical models. similar in their rare chemical Carbon dioxide exsolution causes elements (gold, silver, arsenic, dramatic increases in the solution's Silicate Melt Geochemistry antimony, lead, zinc, and mercury), pH (lowering the acidity level), ranges of temperature and whereas hydrogen sulfide loss to The most abundant material pressure, fluid compositions, isotope the vapor phase causes sulfide erupted from volcanoes is some relationships, and mineralogy of minerals such as sphalerite (ZnS) kind of silicate melt. Depending on ore and altered host rocks. These and galena (PbS) to decompose and the composition and pressure, similarities have prompted many oxidizes the fluid (usually melting temperatures of silicate geothermal companies to adopt the increasing the oxygen partial rocks can range from 800°C to well same exploration strategy to find pressure). over 1400°C. Silicate melts have as economic geothermal systems as Through chemical modeling we their fundamental structural units 4 that used by mining companies in have demonstrated that significant the Si04 - tetrahedral group and gold-silver prospecting-namely to gold transport, as Au(HS)2-, can associated larger cations (positive look for specific trace elements occur at low temperature ( <250°C}, ions) such as calcium, magnesium,

28 OAK RIDGE NATIONAL LABORATORY Review and sodium. At the source of a magmas, are being conducted by can accurately indicate the volcanic eruption, the melt is Mike Naney, Sam Swanson (visiting oxidation state. This need has been .!ommonly a mixture of liquid professor from the University of emphasized in recently published silicate and suspended crystals. Alaska), and me. We are working to reports by Richard Sack (Purdue There may be significant quantities estimate quantitatively the University) and Attila Kilinc of gas such as water vapor, carbon physicochemical conditions (University of Cincinnati), who dioxide, or sulfur dioxide trapped as responsible for magma genesis formulated empirical functions bubbles in the melt that are (pressure, temperature, volatile describing the relationship among released from the magma to the solubility, and oxidation-reduction oxygen partial pressures, Fe2+ to atmosphere during eruption. conditions) and to gain insight Fe3+ ratio, temperature, and bulk Natural molten material of this about the mechanisms (i.e., rock composition. However, kind, called magma, consolidates on crystal-liquid fractionation, trace previous experimental the surface as lava flows or domes, element distributions, and aqueous investigations of the Fe2+ to Fe3+ or it may be ejected explosively into fluid-melt interactions) that control ratios in silicate systems have been the atmosphere to fall as fragments magma evolution in the earth's fraught with problems both in of crystals and glass. In the depths crust. experimental design and in of the earth beneath centers of High-temperature experiments interpretation of data. active volcanism, bodies of magma are conducted at pressures ranging Naney and Swanson designed exist that may solidify completely from 0.1 MPa (1 bar) to 500 MPa experiments to determine the rates without being erupted at the (5000 bars) using the unique of iron oxidation-reduction surface. These masses of molten facilities of ORNL's High reactions for a broad range of material may have volumes ranging Temperature/High Pressure silicate liquid compositions at from a fraction of a cubic kilometer Geosciences Group for studying geologically reasonable oxygen to hundreds of cubic kilometers. oxidation-reduction-dependent partial pressures. Three rock The complexity of the physical reactions. These include a compositions were used: a basalt and chemical behavior exhibited by hydrogen-service internally heated (silica poor, <52% Si02), an these melts arises from the pressure vessel (to 500 MPa) and andesite (silica intermediate, presence of numerous chemical two 0.1 MPa gas-mixing furnaces. 52-60% Si02), and a rhyolite (silica components and their interactions This equipment allows simulation rich, >65% Si02). One-atmosphere over a broad range of temperature, of a wide spectrum of rock-forming experiments conducted at 1243°C pressure, and oxidation states. processes, from 1-atm volcanic and two oxygen partial pressures Knowledge of natural silicate eruptions with surface (log P02 = -7.83 and -6.08) liquids, or magmas, is based largely temperatures in excess of 1200°C to indicate that the Fe2+ to Fea+ on indirect evidence and is conditions 20 km (12 miles) below ratios in basalt and andesite melts primarily confined to their the surface where comparable reach equilibrium in 500 and 1050 compositional variety. The effort magmatic temperatures are min, respectively. In contrast, involved in gathering this type of accompanied by pressures in excess experiments with a rhyolite did not information in field-based studies of 400 MPa (4000 bars). They also equilibrate, or even change Fe2+ to vastly exceeds the work of making provide immediate access to the Fe3+ ratios, in experiments lasting experimental measurements of the simulated magmatic products, while up to 5700 min. physical or thermodynamic natural geologic processes require These data suggest that the properties of magma. Magma, after thousands or even millions of years reaction gases (carbon dioxide and all, is not the easiest material to to expose magmatic products on the carbon monoxide) used in the study; it is hot and often explosive. earth's surface (see box on pages experimental system are less Our understanding of magmatic 30-31). effective in controlling the processes must rely on Oxidation-Reduction Studies in oxidation state in the rhyolite melt experimental geochemical studies Silicate Liquids. One possible because of the slow rates of and draw from related fields of indication of potentially violent migration (diffusion) of these gases materials science and glass volcanic eruptions is the oxidation as well as of other chemical technology. state of the parent magma. Because components compared with the High-temperature and high­ the magma's oxidation state is not basaltic and andesitic melts. The pressure equilibrium and kinetic directly measurable, a related results indicate that the Fe2+ to studies of silicate melts, which are chemical phenomenon, such as Fe +2 Fe3+ ratios in rhyolite and other chemical analogues of natural to Fe+3 ratios, must be found that natural silica-rich rocks extruded

NUMBER FOUR 1984 29 Geochemist's Pressure Cooker Reproduces Rock•Formlng Conditions

~he molten rock that erupts in spectacular displays atmosphere over wide ranges of pressure and 1.1 at Kilauea Volcano in Hawaii or violently at Mount temperature. St. Helens in Washington is produced deep within the ORNL geochemist Mike Naney is using the facility to earth. Researchers in the ORNL Chemistry Division are study oxidation-reduction-dependent processes in silica- using a specially designed internally heated pressure vessel to study the properties of such molten rock (magma) under conditions simulating those 16 km (10 miles) below the earth's surface. The equipment currently operates at hydrogen pressures up to 500 MPa (5000 bars) and temperatures up to 1400°C (2550°F). However, after additional pressure-generating capacity is added to the system, the pressure vessel will be capable of operating at 1000 MPa (10,000 bars), simulating conditions to depths of 33 km (20 miles). Hydrogen is used in this facility to create a reducing atmosphere-that is, it removes oxygen from materials, permitting investigation of oxidation-reduction-dependent reactions that are important in natural magma systems. In the past, use of hydrogen-containing atmospheres to study these reactions was limited and hazardous because Mike Naney locad. the /urnGCe aa•embly and •ample• into hydrogen embrittles steel vessels and thus weakens the internally-heated pre88ure ve88el. The apparatu. i8 them. The novel design of ORNL's pressure vessel uses capable of heating •ample• to 1400°C at hydrogen pre••ure• sealing plugs made of a copper-beryllium alloy and a up to 500 MPa. Hydrogen gaa i8 u.ed in thi. facility to create a reducing atmo.phere--that i8, to remove o%ygen vented liner made of austenitic stainless steel. Because from materiol8, permitting •tudie• of o:ddation-reduction these materials are resistant to embrittlement, hydrogen dependent reaction. that are important in natural magma gas can be used to simulate a deep-crustal reducing •y.tem.. onto the surface can be used as a and solidified silicate rocks under to quantify olivine crystallization. preeruption "fingerprint" of the controlled oxidation-reduction He found that increased viscosity of oxidation state in the parent conditions. the melt inhibits the formation of magma below the surface. Quenching (or fast-cooling) olivine crystals. High viscosities are Oxidation state when combined techniques are being used to usually attributable to silica-rich with other chemical parameters determine the crystallization melts or melts devoid of volatiles (such as water content of the melt) behavior and growth rates of such as water. The initial olivine is a measure of the chemical olivine (Mg2Si04) at 1 atm as a growth rates are two to three evolution of magmatic systems. function of undercooling in two orders of magnitude greater than Because the violence of a volcanic synthetic basalt melts having "average" rates observed for long eruption increases as the magma different viscosities (a measure of times and seem to typify classic evolves chemically, oxidation state the consistency or "stickiness" of "diffusion-controlled" growth. may be a useful guide to assessing the melt). Undercooling is a potential volcanic hazards. crystal-growing technique in which a sample is melted completely; Outlook Crystallization Studies. To better cooled a given increment below its The combination of techniques understand the influence of cooling melting temperature, say 10, 20, or and facilities used in this program history on textural development in 40°C; held at that temperature for to study geologic problems is silicate melts, Naney is a certain length of time; and finally unique and allows unprecedented investigating the formation of quenched. By varying the experimental control over a wide crystals, their growth rates, and magnitudes of the cooling interval range of pressure and temperature their stabilities in silicate liquids and the time, Naney has been able conditions. This capability offers

30 OAK RIDGE NATIONAL LABORATORY Review rich melts. Such melts are analogues for the magmas that cool slowly at depth to form granitic rocks. These rocks form the core of many mountain belts and often AUSTENmC produce rugged landscapes such as Yosemite Valley in STAINL£55 STEEL 1 UNER California or the sheer face of Stone Mountain in Georgia. HIGH PRESSURE Silicic magmas are typically enriched in economically H1 -AIGAS I MIXTURE INLET- important metals-uranium, thorium, copper, tin, 51 em DIAMETER 1201nchool molybdenum, and tungsten-that may form ore deposits. Magmas of this type are currently targets for DOE's Continental Scientific Drilling Program. The ORNL equipment is used to produce synthetic magmas, rocks, and minerals under known temperature, pressure, and chemical conditions. Materials synthesized under known conditions provide geochemists with Schematic cro.. section of the internolly-heated preaau.re references with which to compare natural geologic veaael, which ahowa ita novel design. Austenitic atainleaa materials. The experimental products are characterized steel and a copper-beryllium alloy are used in the areas exposed to hydrogen gas. These materials were selected by the same methods geochemists use in investigating because they reaiat hydrogen embrittlement. If hydrogen natural rocks and minerals. Among the techniques should diffuse through the atainle.. steel liner, the gas ia employed are polarized light microscopy, X-ray swept out through the spiral groove (inset upper right) to diffraction, electron-beam microanalysis, and secondary eliminate embrittlement of the load-bearing 434() alloy steel. ion mass spectrometry. By comparing mineral The platinum membrane ia used to osmotically control the hydrogen content of the hydrogen-orgon gas mixture in the constituents and their chemistries in natural rocks with pressure veaael. Samples, which are contained in sealed those in compositionally similar synthetic rocks, platinum tubes, may consist of powdered roclc. water, and geochemists can estimate the pressure and temperature gases such as carbon dioxide. Inside the preaau.re veaael the conditions that existed during the formation of the natural aamplea are subjected to preaau.re and temperature material. conditions simulating those deep in the earth'• crust. the possibility of quantitatively properties of silicate melts and describing, through integrated aqueous geochemical fluids and research, the evolution of their role in elemental transport geochemical systems from and rock transformations. magmatic to ambient conditions. ORNL will continue to Hence, for the future, it will be coordinate experimental technically feasible and investigations of fundamental scientifically sensible to consider geochemical problems and thereby geochemical problems that traverse accelerate the progress of scientific the boundaries of traditional understanding of large-scale crustal disciplines in geochemistry (e.g., processes. The scientific knowledge igneous petrology, metamorphic gained will have practical benefit petrology, and hydrothermal for problems associated with geochemistry) by treating the underground waste disposal, intensive parameters of geological enhanced oil recovery, petroleum systems as a continuum. With this and natural gas exploration, approach new perspectives and geothermal and magma energy research tools can be used to development, and the exploration address broader scientific questions and extraction of mineral resources. of both academic and practical importance. Among the problems amenable to this strategy are

NUMBER FOUR 1984 31 ( take a number 2a BY V . R. R. UPPULURI 3 8!3 ~

More on Squares Convergence by Repetition

The successive integers 3, 4, 5 have a curious Take the number 6. Take its square root and add 6 property. The sum of the squares of the first two to the result. Take the square root of this answer and numbers equals the square of the third number. Thus 32 add 6 to it. Continue this process, and soon you will + 42 = 52 (9 + 16 = 25). The only other three obtain the number 3. successive integers that have this property are - 1, 0; 1. Similarly, take the number 24. Take its cube root and The five successive integers 10, 11, 12, 13, 14 also add 24 to the result. Take the cube root of this result have this property. In their case, the sum of the squares and add 24 to it. Continue this process. In a short time, of the first three numbers equals the sum of the squares your calculations will converge to 3. of the last two numbers. Thus 102 + 11 2 + 122 = 132 Now, take the number 78. Take its fourth root and + 142 (100 + 121 + 144 = 169 + 196 = 365). add 78 to it. Take the fourth root of this result and add Only one other series of five successive integers has this 78 to it. Continue this process, and once more you will property: -2, -1, 0; 1, 2. quickly converge to 3. One can raise the question abou1 seven successive How abou1 fifth roots? If one wants convergence to 3, integers: Are there cases in which the sum of the it can be done by selecting the proper number. squares of the first four integers equals the sum of the squares of the last three integers? Only two such sequences exist. These are 21, 22, 23, 24; 25, 26, 27 and -3, -2, -1, 0; 1, 2, 3. One can verify that 21 2 + 222 + 232 + 242 = 252 + 262 + 272 (2020); (-3)2 + (-2)2 + (-1)2 + (O) = 12 + 22 + 32 (14).

32 OAK RIDGE NATIONAL LABORATORY Review ------

research at the medical school at Pahlavi University in Shiraz, Iran. In 1977 she joined the faculty of the University of Pennsylvania. At ORNL her research interests include water chemistry and health effects, cardiovascular diseases, and occupational epidemiology. Here, she points to regions of the United States where ORNL has conducted cardiovascular disease studies. Listening to her are, from right, Hazel Burum (HASRD), who did the clerical and administrative work associated with the study; Max Morris of ORNL's Engineering Physics and Mathematics Division, who did the statistical analysis; and Annetta Watson (HASRD), who is working in the area of drinking water research and dietary calcium studies. Elaine Zeighami is leader of the Health member. A native of Perry, Oklahoma, This group looked at questions Effects and Epidemiology Group in she earned a Ph.D. degree in concerning the potential impact on ORNL's Health and Safety Research epidemiology in 197 4 from the cardiovascular disease risk of drinking Division (HASRD). She joined HASRD in University of Oklahoma. She spent the water intake of both toxic metals and August 1979 as a research staff next three years teaching and doing essential nutrients.

A one-liter glall• of tap water typically contain. 10-50 millilfnJIM (mg) of calcium 5-ZO mg magne•ium 10-40 mg sodium 1-8 mg potas•ium Drinking Water and O.Z-1.5 mg iron 0.1-0.5 mg zinc 0.01-.Z5 mg copper O.Z-Z micrograms (I'll) Cardiovascular Disease of cadmium 3-7 I'll lead 0--1 mg reaidual chlorine varying amount• of chlorinated organic•

By ELAINE ZEIGHAMI

17'\\ iseases of the cardiovascular attack. About 46% of all deaths the oxygen supply is cut off from l..W system account for more than among men from 50 to 59 years old the brain tissue. In both instances, half of the deaths in the United are caused by heart attacks. one common cause (perhaps the States each year. The most common Myocardial infarction results most common) is the blockage of an causes of death are myocardial from the death of cardiac tissue artery by the buildup of infarction (heart attack) and caused by a decrease or total cutoff atherosclerotic lesions within the cerebrovascular accident (stroke). of blood supply, and consequently artery. These lesions begin as lipid Men in their forties and fifties face oxygen, to some portion of the deposits (including cholesterol), an especially high risk of heart heart muscle. A stroke occurs when which subsequently calcify.

NUMBER FOUR 1984 33 Most programs to prevent heart An epidemiological study of Wisconsin farmers indicates that persons attacks and strokes have therefore with cardiovascular disease drink softer water than persons without the concentrated on making changes in disease. those "big three" factors, and recent evidence from prevention trials has demonstrated the efficacy of that focus. These risk factors for cardiovascular diseases depend largely on "personal" lifestyles (e.g., what we individually eat and drink, how we exercise, and how much we smoke); thus these factors are, to some extent, under individual control. Unlike cancer risks, for which considerable evidence exists that environmental exposure to carcinogens plays a role, little is known about the role of environmental exposures in causing cardiovascular diseases. There are, however, several possible such SURFACE WATER exposures of significance to the human cardiovascular system. Chemicals known to have deleterious effects on the cardio­ Hardness as C aC 0 1 in parts per mill ion c::J less than 60 ppm EJ from 60 to 120 prm ('::;::;:;::::j from 120 to 180 ppm vascular system include carbon B from 180 to 240 ppm - 240 ppm and over disulfide and nitroglycerin, at levels of exposure encountered in the occupational environment. In the general environment, carbon monoxide, lead, and cadmium are all strongly suspected of having harmful effects on the cardiovascular systems of exposed humans. Food and drinking water can both be sources of exposure to some potentially deleterious substances, of which lead and cadmium are examples. In addition, intake levels of some nutrients have been suspected of having either beneficial or harmful effects on the cardiovascular system. These GROUND WATER nutrients include calcium, magnesium, sodium, and potassium.

Study of Wisconsin Farmers Water hardne88 i3 determined by calcium and magneaium content of the water. Primary risk factors for heart The epidemiology research TenneBBee and moat Btatea in the attack include elevated blood group at Oak Ridge National Southeaat generally hove ao(t water. The pressure, elevated blood lipids, and Laboratory has been looking at hordeat watera in the United Statea are smoking. For stroke, elevated blood found in the Great PlaiRB Btatea. questions concerning the potential pressure is the primary risk factor. impact on cardiovascular disease

34 OAK RIDGE NATIONAL LABORATORY Review ------

For analytic pKrpoBeB, Wisconsin waB divided into siz regions. Region Z has the hardest woter and waB the only region in which there waB no evidence that CGBeB (people with cardiovfJBcKlar disefJBe) had •offer water than controls. In all other regions, cfJIJes drank softer woter than controls. REGION 6 Lead and cadmium in drinking REGION 5 water arise principally from the leaching of those two elements from pipes and from solder. Other metals, such as iron, may enter drinking water both from geochemical sources and from REGION 4 pipes. Nitrate contaminates groundwater principally by REGION 3 nitrogen fertilizer runoff and by water runoff from manure. Calcium and magnesium, which are essential nutrients, are bulk elements in drinking water. "Hard" water, which is water high in calcium and magnesium, may supply as much as REG IO N 2 20% of the average intake of these REGION 1 nutrients. The study of Wisconsin farmers eventually enrolled 520 cases (persons dying with one of the two conditions) and 854 controls (persons without disease). Controls were drawn from lists maintained risk of toxic metals and essential water intake of inorganic elements by the Wisconsin Department of nutrients consumed in drinking among two groups of Wisconsin Agriculture. The number of water. ORNL staff working with me farmers-white males dying from controls selected in each county on the project include Jeanne Calle coronary artery disease (principally represented that county's and Annetta Watson of the Health heart attack) or stroke and white proportion of farmers in the state. Effects and Epidemiology Group of males having no evidence of Data obtained from respondents, or the Health and Safety Research disease. All the respondents their wives, included information Division and Max Morris of the obtained their drinking water from concerning their length of Engineering Physics and their own wells. Inorganic elements residence, use of drinking water, Mathematics Division. The and compounds were identified and diet, smoking history, and medical University of Wisconsin and the quantified by sampling from the history. For cases, a medical Wisconsin State Hygiene kitchen cold water tap. The history was obtained from their Laboratory have analyzed water inorganics measured included lead, physician. All persons in the study samples for the study involving cadmium, iron, nitrate, calcium, had lived at their residences at Wisconsin subjects and provided magnesium, sodium, copper, and least two years. water chemistry expertise. A field manganese. The pH of the water The data indicated that in office was maintained in Madison, was also measured because the level comparison with persons without Wisconsin, for the period of the of acidity influences corrosivity of the disease, those with disease first study. the water as it passes through and more often had a "soft" water This three-year study has been resides within tanks and pipes of supply-that is, water with a lower completed. It examined drinking the distribution system. calcium and magnesium content

NUMBER FOUR 1984 35 ORNL researcher• are studying the calcium intal&e from dairy food• and drinking water of three CGBe group• in a population: (1) thoiJe wlw died from coronary artery disease or atroke and had FOOD AND WATER a physician diagr&oaia of high blood CONTROLS pressure, or hyperteRBion (hyperteRBive FOOD ONLY CGBeB), (Z) thoiJe wlw died from coronary artery disease or atroke but had RO FOOD AND WATER phyaieian record of hyperteRBion NONHYPERTENSIVE CASES (nonhyperteRBive CGBeB), and (3) thoiJe FOOD ONLY not known to have cardiovascular disease condifioRB or hyperteRBion (controla). So far, their finding• indicate that peraoRB FOOD AND WATER HYPERTENSIVE CASES without cardiovascular disease or FOOD ONLY hyperteRBion tend to have a higher calcium intal&e than do diseased CGBeB. I I I than is typically present in hard 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 water-and were more likely to CALCIUM INTAKE (mg/d) have measurable lead and cadmium in their drinking water. relationship, which could have study, lead and cadmium intake Wisconsin was divided into six enormous implications for the from water is less than 1% of the regions to permit studies of prevention of hypertension (high intake from food. The higher levels regional variation. Although cases blood pressure). of those two metals possibly reflect and controls were not identical in As expected, the relationship higher levels of corrosive leaching regional distribution, the two between low calcium and from piping systems delivering groups were very similar in region magnesium intake and increased water to cases rather than to of origin (place of residence). The risk of cardiovascular disease was controls. Levels of these metals southern part of the state contains not strong, with an odds ratio of 1.1 were generally higher in the water the hardest water, and the two (a 10% change in probability of consumed by older members of the northernmost regions have the being a case) associated with a case group; the reason for this softest water. Within all the 100 mg/L decrease in water age-metal content correlation may regions except one, the case group hardness. By contrast, smoking one be that older people have older had been drinking softer water pack of cigarettes per day changes homes with piping systems that than controls. risk by 50 to 100% . We also have corroded extensively over While a soft water-higher estimated calcium intake from time. These relationships require cardiovascular death rate dairy products, based on responses further delineation before any relationship has often been to dietary information. The inferences can be drawn. observed on a geographic basis, this estimated odds ratio for calcium study is the first to observe the intake from dairy products was Death Rates and Regions relationship in a large group of nearly identical to the odds ratio Observations of the relationship individuals. Because calcium and for calcium intake from water. Of of hard water intake to lower death magnesium levels are so closely course, establishing the accuracy of rates from cardiovascular disease related in drinking water, any dietary estimates is difficult. were first made about 40 years ago. separating the effects of the two Lead and cadmium were also In several countries, including the was impossible. However, recent more frequently detectable in the United States, soft water areas evidence obtained by others has water of Wisconsin cases than in have higher death rates from indicated that calcium intake may that of controls. These elements cardiovascular disease than do hard be inversely related to blood were almost without exception water areas. In the United States, pressure-that is, low intake of present at extremely low levels, certain parts of the Southeast, calcium may increase blood representing only a small fraction particularly the lower Atlantic pressure. These recent findings, if of daily intake of those metals. coast, have the highest death rates confirmed, may provide new leads Only 20-30% of the water samples from cardiovascular disease. in the puzzle of the had detectable levels of either Although these areas also tend to water-cardiovascular disease element. At the levels found in this have the softest waters in the

36 OAK RIDGE NATIONAL LABORATORY Review ----·------

CALCIUM LEVEL IN DRINKING An intake of ZL/d of hard water could WATER (mg/L) make a meaningful contribution to total calcium intake for population groups who have inadequate dietary intake, such as MEDIAN DAILY black or white females and black males. GROUP DIETARY INTAKE 10 40 80 For people whose water is soft or (mg) AVERAGE CONTRIBUTION OF moderately hard (like water in Oak DRINKING WATER (%) Ridge), two large glasses of milk each day or calcium supplement tablets may be needed to ensure that they get the WHITE MALES 778 3 10 21 recommended level of 800 mg/d of WHITE FEMALES 526 4 15 30 calcium. BLACK MALES 548 4 15 29 BLACK FEMALES 371 5 22 43 disinfection. Groundwater may be treated with chlorine. In drinking water, chlorine combines with ASSUMES AVERAGE INTAKE OF TWO LITERS PER DAY. THE CALCIUM CONCENTRATIONS GIVEN CORRESPOND ROUGHLY TO A TOTAL HARDNESS OF -45 mg/L (CALCIUM= organic material to form various 10 mg/L); -180 mg/L (CALCIUM= 40 mg/L): AND -360 mg/L (CALCIUM= 80 mg/L). chlorinated organic compounds. The principal such compound is country, other characteristics exist water are principally calcium and chloroform, although other that distinguish high-rate regions magnesium, although drinking trihalomethanes are also formed. from low-rate regions of the water does contain some essential The principal health-effects country. Altitude is one geographic trace elements, such as zinc and concern about chlorinated drinking factor that has been suggested as a copper. As previously mentioned, water has been the possible possible contributor. High-rate recent evidence has lent some carcinogenicity of ingested areas in the United States tend to support to the hypothesis that low chlorinated organics. The fact that be at low altitudes. On the other calcium intake is linked to elevated chloroform has been found in some hand, people who live in the Rocky blood pressure in humans. In animal studies to be carcinogenic Mountains, which have the highest addition, animal studies have raises questions about the possible altitude in the United States, shown that heavy metals, such as cancer-causing effects of chlorine exhibit the lowest cardiovascular lead and cadmium, have an and chlorinated organics at the death rates. enhanced ability to elevate blood much lower dose levels ingested by The question of a relationship pressure in calcium-deficient rats. humans. between the high intake of soft Magnesium deficiency also The consumer of drinking water water and the high rate of death apparently escalates the toxic also ingests residual chlorine in from cardiovascular disease has effects of lead and cadmium in varying amounts, depending on the always been clouded by the raising blood pressure. In view of nature of the treatment. Recently fundamental uncertainty of these studies, questions about the work by Nathaniel Revis, formerly whether hard water contains contribution of hard drinking water of the ORNL Biology Division and beneficial elements or whether soft to calcium and magnesium now director of the Oak Ridge water contains toxic elements-or nutrition and the impact on the Research Institute, and by the conceivably both. Soft water is cardiovascular system need to be Environmental Protection Agency more corrosive and therefore evaluated. (EPA) has indicated that chlorine generally picks up more metals, ingestion itself may also be a Drinking Water Treatment such as lead and cadmium, in the problem. It may affect thyroid distribution system. In animals, the Drinking water in the United function and raise blood pressure effects of high intake of lead and States may come either from a and cholesterol levels in rats. This cadmium on the cardiovascular public supply or from a private finding has stimulated further system, particularly blood pressure supply. Private supplies are interest in studying chlorine elevation, are firmly established. generally well water and are ingestion in humans. For humans, however, intake of usually not treated. Public supplies In 1985 our group will begin an these elements through drinking are either groundwater or surface EPA-sponsored project in several water is, with few exceptions, only water such as a river or lake. states to examine more closely the a tiny fraction of their intake from Surface water supplies are almost relationship between levels of blood other sources, mainly food. without exception treated with pressure and blood lipids in humans Beneficial elements in hard some form of chlorine for and the total intake of chlorine and

NUMBER FOUR 1984 37 Moat of the Wiaconain farmers aw-veyed by the ORNL epidemiologicc&l afl&dy live cmd worh on dairy farms aimilor to thia one. The farmers were chosen for the afl&dy because they have their own wells cmd eonaume virtually all their driuing water {rom one source.

of calcium (from both food and which occurs mainly in infants, suggest that the human thyroid can water). impairs the ability of the blood to be adversely affected by chemicals transport oxygen to tissues. in drinking water such as resorcinol High nitrate levels in drinking Other Drinking Water Hazards (see "Environmental and Health water are strongly suspected of Impacts of Water Chlorination," Pollutant contamination of causing high abortion rates and pages 44-49). drinking water is one of the possibly congenital malformations Pollutants in drinking water principal environmental concerns of in livestock. Recent evidence of could have a variety of effects. both the present and future. While high rates of certain types of Concern centers primarily on this concern has tended to center congenital malformations in carcinogenesis, potential on industrial pollutants in urban humans exposed to high nitrate reproductive effects, diseases of the drinking water, groundwaters are levels in drinking water has cardiovascular system, and reduced also a target for pollutants from a reopened inquiries into the thyroid function. Drinking water is variety of sources. In rural areas potential effects of nitrate a universal source of nutrients and nitrate contamination of drinking ingestion. toxic metals, and even small effects waters caused by runoff from Research performed at ORNL, could have a major impact on nitrogen fertilizers and manure is a under the direction of Bob Jolley of public health. For this reason, we major problem. High nitrate levels the Chemical Technology Division, intend to work with other scientists in drinking water are established as has helped to identify substances in at ORNL and at other institutions the cause of methemoglobinemia, a drinking water that decrease to develop further approaches to condition caused by the conversion thyroid function. These substances understanding the impacts of of hemoglobin in the blood to are called goitrogens. Studies at drinking water on human health. methemoglobin. The condition, ORNL and elsewhere increasingly m

38 OAK RIDGE NATIONAL LABORATORY Review 1 technical capsules

The structure of water and other distribution function from X-ray Neutron and X·Ray Diffraction liquids is not the same as the structure diffraction. This work confirmed the Stuclea Shed Ught on of crystalline solids. Atoms in crystals open tetrahedral arrangement Oike the Structure of Water are arranged in a periodic order that corners of a triangular prism) of the repeats itself throughout the solid. The oxygen atoms in water and has ~ cientists have been studying water structure of liquids, however, refers to provided a crucial test of proposed ~ for centuries but so far have not the relative average location of water models. come up with a definitive theory of the molecules and distances between In 1981 Narten and Thiessen structure of liquid water. However, they specific atoms on molecules. Thus when completed a long and difficult neutron have proposed and developed water AI Narten and Bill Thiessen of the ORNL diffraction study of light- and heavy­ models. These models can now be Chemistry Division study the structure of water mixtures at ORNL's High Flux tested by comparing their predicted water, they measure interatomic Isotope Reactor. This work, which could results with actual measurements of distances-that is, distances between be carried out only at ORNL's unique interatomic distances and other hydrogen atoms on different water facilities, has yielded the O.H and H-H structural information obtained by molecules and distances between atom pair distribution function not neutron and X-ray diffraction studies at oxygen atoms on different H20 (water) previously known. Oak Ridge National Laboratory. Once molecules. A measure of the interatomic • As a result of our work," says the models are modified so that their distances between oxygen atoms is Narten, "there are now three distribution results fit the ORNL data, a realistic called the "oxygen atom pair distribution functions available for inferring the statistical mechanical theory of liquid function." positional and orientational correlations water could be developed. The ORNL ORNL has a long, distinguished between water molecules. This X-ray data also may be used for history of work on the structure of liquid structural information will provide a improved medical diagnoses. water. At the Graphite Reactor in 1946, sensitive test of proposed water models Ernie Wollan and Cliff Shull made the and should lead to a realistic statistical Model for the average orientation of pairs first measurement of the neutron mechanical theory of liquid water." of near-neighbor molecules in liquid diffraction pattern of water. In 1966 water. Large local and instantaneous Narten, Merle Danford, and Henri Levy deviations from this average obtained the oxygen atom pair Intermolecular atom pair distribution configuration occur in the liquid. functions for liquid water at Z5°C. 5,------, Water, 25°C -goo I 4 : - - - - 90H (r) ~ ...... g HH (r) .'•. '• ,,,, ::'• ,,,, 3 ..:: ,, ' • ,, ..:: ::., : '• : :: i ; .I .I : :: : ::I I I; • : .' t : : :i / : :i / / ; :i // . ' / / .' . / / .' ., / / . ;, / .• ..:.o ,• 0 ......

-1 ~--~---r--~---.----r---~--~---r---r---1 0 2 4 6 8 10

NUMBER FOUR 1984 39

- ·------' • technical capsules

TID. ecause hydrogen atoms have only of the University of Puerto Rico, caused by X rays scattered away from l.illone electron each and because published their results in the the primary beam and into the detector X rays are scattered from electrons, September 10, 1982, issue of Science. by water in the body. By using ORNL neutron scattering is the only useful The ORNL chemists found that the X-ray cross-section data, physicists method for locating the positions of distance between oxygen and hydrogen have developed correction methods for hydrogen atoms in crystals and liquids. within a molecule is 0.96 A, that the taking out the scattered radiation and Levy, in fact, was the first to use distance between an oxygen atom on a producing an enhanced image that is neutron scattering to find the positions molecule and a hydrogen atom on the less ambiguous than the normal X-ray of hydrogen atoms in single crystals. To nearest molecular neighbor is 1.86 A, image. Such enhanced images are find the relative locations of hydrogen and that the distance between oxygen especially significant for three­ atoms in water, Narten and Thiessen atoms on adjacent molecules is 2.85 A. dimensional, low-energy X-ray studies of used samples prepared with four These results, states the Science the lower abdomen, where up to 20% of different mixtures of light (H20) and article, "suggest that most water the primary beam is scattered. The use heavy, or deuterated, water (D 20). molecules are connected to their of the ORNL data for these correction Light and heavy water scatter neutrons nearest neighbors through nearly methods was reported in the Journal of differently. By intercomparing data straight hydrogen bonds." Physical Chemistry in 1982 and Medical obtained for the different mixtures, the X-ray diffraction measurements of Physics in 1983. researchers made an unambiguous, water made at ORNL have proved Finding the structure of water is still direct measurement of the ~. Q-H, useful to radiologists seeking to correct a struggle, but work at ORNL is guiding and H-H interatomic distances and for lowered resolution and contrast in the theorists in the right direction and coordination numbers. Narten and X-ray images of body organs or tumors. helping medical diagnosis as well. Thiessen, in collaboration with L. Blum This degraded resolution and contrast is

Iodine Hydrolysis: a strategy for its removal and reduce released during an accident would A. Key Reaction In Nuclear the need to evacuate area populations. remain effectively trapped in the water. Regulators wish to ascertain the However, scientists have been Accident Scenarios volatility of iodine species to assess concerned that further oxidation their impact on the environment. reactions, including those caused by ~ ne of the scientific lessons of the Scientists must try to unravel the radiation in the reactor, may transform ~ March 28, 1979, accident at the reactions that occur during various 1- to other more volatile forms, such as Three Mile Island (TMI) nuclear plant accident scenarios to be able to predict molecular iodine (12) and the transient was that the releases of radioactive the amounts and the nature of the iodine hypoiodous acid species (HOI). iodine (1311) to the environment were species formed. Molecular iodine, in particular, is not much lower than anticipated. In fact, Four years ago, Dave Campbell and inert. It reacts with water, or less than 0.001% of the iodine that Tony Malinauskas of ORNL's Chemical hydrolyzes, by a complex series of escaped from the ruptured fuel elements Technology Division, in collaboration interrelated pathways. The key reaction could be detected outside the with Bill Stratton of Los Alamos National is an oxidation-reduction, or redox, containment building. The amount of LabOratory, provided a very plausible process that converts the potentially iodine released from light water reactors explanation for the behavior of iodine at volatile 12 molecule to the nonvolatile during loss-of-coolant accidents is thus TMI. (See "Iodine and Reactor ions 103 - (the oxidized form) and 1- expected to be almost negligible. Accidents," ORNL Review, Spring (the reduced form). This redox process Because ingestion of 1311 can cause 1982.) They stated that 1311 escaped is extremely sensitive to changes in cancer of the human thyroid, this is from the fuel as the core temperature temperature, in the acidity of the water, welcome news. rose from 1000 to 2000°C and then and in the concentrations of the iodine Since the TMI accident, emergency combined immediately with the excess species involved. planners, regulators, and scientists have cesium (Cs) present in this highly To better understand and quantify sought to determine whether any reducing atmosphere to form the iodide some of these processes, research condition exists at which volatile 1311 salt Csl, rather than persisting as highly efforts were undertaken within the might escape in some form to the volatile elemental 1311. Because Csl is Chemistry and Chemical Technology environment. Emergency planners want highly soluble in water, it was readily divisions of ORNL. (The important to know the anticipated level of iodine dissolved in the emergency cooling questions of the volatility of iodine release during loss-of-coolant accidents water to form nonvolatile iodide ions, 1-. species and the kinetics of the in pressurized-water reactors and If this were the end of the reaction hydrolysis reaction have been boiling-water reactors in order to devise sequence, the radioactive iodide ions extensively studied in the Chemical

40 OAK RIDGE NATIONAL LABORATORY Review Don Palmer Gild Diclc Barnette read Technology Division by Mac Toth and of the Great Lakes College Program at voltage• recorded from an electrochemical cell inaide a conatant­ his colleagues in a program for the U.S. ORNL), collaborated in developing a temperat.re water bath. By recording the Nuclear Regulatory Commission. These unique cell design to implement this voltage difference•, they can meaaure the questions are not addressed here.) technique. The two-compartment cell extent, or equilibrium diatribution, of the To answer the question concerning that they designed allowed iodine to oxidation-reduction proceaa that reaulta the stability of iodine in water, physical migrate freely between the two redox­ when diaaolved molecular iodine react• chemists in the Chemistry Division's partner solutions. Given time, the iodine with water. High Temperature Aqueous Chemistry concentration eventually attains the Group originated an approach for same value in both solutions. This contribution to basic solution chemistry. studying the principal hydrolysis condition enabled the researchers to They provide a new verification of the reaction, the formation of iodate (103 - ) make exact measurements of the preferred model for predicting and iodide (1 - ) ions. The method concentrations of all iodine species temperature variation of thermodynamic involves splitting the reaction into its two present, including the elusive 12 . quantities. redox partners, the oxidizing haH with 12 Because of the low concentrations The transient species HOI has also and 103 - and the reducing haH with 12 present, however, better methods of been considered a possible and 1-. Together they make up two analysis were necessary. environmental hazard if released in a compartments of an electromotive force Ramette used his considerable nuclear accident. Its existence in (emO cell. This arrangement constitutes experience with the precise technique of solution is known from equilibrium and a battery whose potential very potentiostatic coulornetry, a sensitive kinetic observations, but spectral accurately indicates the equilibrium analytical method for identifying and evidence for its existence has been distribution of all the species. This quantifying reducible species, such as lacking. Palmer has used controlled general method is often employed at iodine, to meet this need. This approach chemical conditions, with removal of room temperature for other redox proved highly successful; from the interfering species, to observe a weak systems, but has never been attempted results, the exact concentrations of ultraviolet band that could be due to until now on iodine species or at iodine and the other major components HOI. H this proves to be the HOI temperatures as high as 210°C. can now be predicted at conditions spectrum, it would be the first reported Two physical chemists, Donald similar to those considered in reactor physical property for the species. Palmer of ORNL and Dick Ramette, a accident scenarios. Besides this chemistry professor from Carleton relevance to nuclear technology, the College (who is serving as coordinator results have provided an important

NUMBER FOUR 1984 41 Chang-laBru~n Chen (left) and Steven Kramer were among the Howard Adler (left) and Weldon Crow developed an enzyme developers of a laser-based detector, which can identify and co•nt syatem for growing ozygen-sensitive bacteria quickly and Bingle atoms of rore gases, permitting researchers to measure the conveniently. This process could aid in the diagnosis and age of polar ice and determine safe locations for disposal of treatment of important human and animal diseases. n•clear wastes.

ORNL Scientists Win Four HI 100 Awards ll®®Tioffi ______

/1)\ ak Ridge National Laboratory has application is in clinical laboratories, specifically for marketing the enzyme ~ once again shown itself to be where bacteria that produce diseases in system. Adler believes that clinical among the leading U.S. research and animals and humans are grown from laboratories are a certain market and development (R&D) organizations in tissue samples and tested for sensitivity that municipalities, chemical and originating technological advances to antibiotic drugs. The enzyme system biotechnology companies, and R&D having possible commercial applications. could be used to maintain oxygen-free laboratories are possible markets. An annual competition sponsored by conditions necessary for culturing the oxygen-sensitive bacteria that cause Research & Development magazine Single-atom detector. A detector infections. Other possible applications (formerly Industrial Research & that identifies and counts single atoms are Development) yielded five of rare gases was developed by awards for the Martin Marietta Energy G. Samuel Hurst, Marvin G. Payne, Systems, Inc., facilities in Oak Ridge. • Municipal waste treatment Steve L. Allman, and Ronald C. Phillips Four of these were awarded to systems-to promote the growth of in the Photophysics Research Group of scientists at the Laboratory for anaerobic bacteria used to break down the Health and Safety Research technologies judged to be significant Division. According to Payne, advances or to have market potential. wastes • Chemical synthesis-to maintain applications that are "ready to go" deal reduced environments in which to with basic physics studies. A potential Anaerobic environments. Howard I. synthesize oxygen-sensitive chemicals environmental application is the Adler and Weldon D. Crow of the • Isolation of biological catalysts detection of argon-39 in the ocean. Biology Division were honored for the (enzymes)-to maintain reduced Determining argon-39 content permits development of an enzyme system that environments in which to isolate scientists to chart circulation currents quickly and conveniently provides a oxygen-sensitive enzymes and mixing times as a way of suitable (anoxic) environment for determining the uptake by the oceans of oxygen-sensitive (anaerobic) bacteria, carbon dioxide, including that replacing expensive inorganic catalysts The enzyme system is already discharged by combustion of fossil fuel. containing platinum or paladium. (See patented. Adler says that development Another possible use is detection of Adler's • A Novel Way To Grow of a marketable product could go either krypton-81 to estimate how long Anaerobic Bacteria," ORNL Review, to a company that would add it to their groundwater has resided in a particular Winter 1983.) current product line or to an Oak Ridge location without mixing with surrounding Adler says that an almost certain company that might be created water sources. In October 1984 the

42 OAK RIDGE NATIONAL LABORATORY Review Paul Satterlee (formerly of ORNL), H. Lee Martin, and Joseph E. Herndon (right) developed the Model M-Z Control System, a sophisticated microprocessor-based control system for Gerald Schulze (le/f) and Herbert Mook developed an an advanced servomanipulator ~&Bed for remote maintenance of ultrasonically-pulsed neutron time-of-flight spectrometer, which components in indl&8trial environments inacceuible to direct dramatically increases reactor-produced neutron inteRBity for human entry. scattering research.

ORNL researchers used the rare gas detection system and is pursuing the with the system. Besides its fuel-recycle counter on the first practical sample: nuclear waste disposal application. application, the control system could be 1 L of groundwater from Switzerland. used by orbiting space laboratories for Servomanipulator digital control They counted about 1000 atoms of satellite repair. "Although the system is system. H. Lee Martin [Instrumentation krypton-81 in the water-equivalent to currently prohibitively expensive," says and Controls (I&C) Division] and Martin, "the next-generation controller, finding a grain of sand on Coney Island. Joseph A. Herndon (Fuel Recycle which we are now developing, will be Information on the krypton-81 content of Division) along with Paul E. Satterlee constructed from off-the-sheH water can help geochemists determine (formerly of ORNL) were honored for components, making it much less the age of water in geological their work on a digital control system expensive. n sediments. It is also invaluable in finding for an advanced servomanipulator. environmentally safe locations for the According to Martin, previously used Ultrasonically pulsed neutron disposal of nuclear wastes-that is, analogue systems were not amenable to spectrometer. A high-resolution, underground areas protected from the modification and required frequent ultrasonically pulsed neutron time-of­ flow of water, which can leach out adjustment to perform acceptably. The flight spectrometer developed by isolated radioactive materials. digital system is more reliable and Herbert A. Mook (Solid State Division) The group will be looking for funding provides more information on and Gerald K. Schulze (I&C Division) to use the technology to detect the manipulator operation. was also an 1-R 100 winner. The presence of lead atoms in thallium ores spectrometer, which greatly increases The control system was developed as a way of inferring the passage of reactor-produced neutron intensity, is a specifically for the Fuel Recycle Division solar neutrinos through the earth. Solar significant advance that will have a for remotely handling hazardous neutrinos, which provide information definite impact on neutron-scattering materials, such as radioactive fuels about the interiors of stars, are particles research. Patents have been applied (uranium and plutonium) removed from created by particle decay in the sun for, but because neutron scattering is spent fuel elements for reuse in new fuel that have virtually no mass and that exclusively a research field at this time elements fabricated for nuclear interact weakly with matter. The solar and the number of reactors used for this reactors. This system was developed in neutrino study may be funded on an purpose are few, development of this cooperation with Central Research ongoing basis within the next couple of technology to a marketable system is Laboratory (CRL), a commercial years. unlikely.- Lydia Corrill. !!:!1 A spin-off company, Atom Sciences operation in Red Wing, Minnesota. CRL of Oak Ridge, holds the patent for the owns all patents and licenses connected

NUMBER FOUR 1984 43 Bob Jolley (right), Dr. Eduardo Gaitan (center), and Nathaniel Rev~. director of Oak Ridge Research lutitute (and former staff member of ORNL's Biology Div~ion), d~cuss chemical spectra prod~&ced by the analys~ of drinking water samples sent by Dr. Gaitan to Jolley. Dr. Gaitan conferred with Jolley after giving a seminar to ORNL staff members September 4, 1984. Jolley and h.~ collealfi&6S hove fo~&nd in several samples a chemical known to cause thyroid d~ease.

Environmental and Health Impacts

By CAROLYN KRAUSE

n the early 1970s when Bob thesis topic, however, he chose to is added to wastewater. A few Ti Jolley, a chemist at Oak Ridge examine wastewaters for organic months later, his results were National Laboratory, began work compounds that might be formed as corroborated in a paper published on his doctoral thesis, he was a result of the addition of chlorine, by Bill Glaze, then with North unknowingly getting a taste of a which is used to kill disease-causing Texas State University and now new career. Since that time, his bacteria. In his 1973 dissertation, with the University of Texas at watchwords have been organics and Jolley identified and quantified 17 Dallas. The same year, a Dutch organizing. He has become an chloroorganics produced during the scientist, John Rook, announced in expert on identifying and chlorination of wastewater and a paper that he had found quantifying organic compounds in suggested that research be done to chloroform, a chlorinated organic water-including potentially determine whether these organics compound, in drinking water in hazardous compounds in drinking pose any health hazards. Holland. At about the same time, water-and has been responsible In 1974 Jolley was first to Jim Liechtenberg and Tom Bellar for organizing five international publish a paper announcing to the at the Cincinnati regional office of conferences on the health and scientific world that chlorinated the U.S. Environmental Protection environmental impacts of water organics are formed when chlorine Agency (EPA) reported that they chlorination. Before Jolley became a doctoral candidate at the University of ORNL chemist Bob Jolley was the first to identify potentially Tennessee, he had been using liquid hazardous organic compounds formed by adding chlorine to waste­ chromatography in ORNL's water. He has also led an effort to identify drinking water compounds Chemical Technology Division to analyze wastewaters and body that cause thyroid disease. fluids for organic materials. For his

44 OAK RIDGE NATIONAL LABORATORY Review .Tolley and NormtJII, Lee ~~aed em. ga. clu-omotograph-ma,. apecfromefer eo identify reaorcinol in drinlc.ing wafer aamplea aupplied by Dr. Gaitan. Beaorcinol ia a goitrogen-that ia, if can cauae enlargement of the thyroid Lee esaminea the inferior coil of the ga. and lead eo health problema. chromatograph a. if awaiea repair.

of Water Chlorination

had identified chloroform in environmental effects of different chlorinated organics in chlorinated drinking water in chlorinated organics. In 1974 Jolley these cooling waters. Cincinnati. began obtaining samples of waters Gehrs then undertook to As a result of this flurry of used in cooling power plants to determine whether these organics reports about chlorinated organics determine whether they contained were toxic to water fleas (Daphnia). in water, EPA in 1975 started a chlorinated organics. Chlorine is After subjecting the Daphnia to national reconnaissance survey to routinely added to power plant different concentrations of determine the extent to which cooling systems-both once-through organics, Gehrs and later John chlorinated organics were present systems and recirculating systems Trabalka of ESD found that at high in drinking water in U.S. cities. The with cooling towers- to destroy concentrations, several of the EPA survey showed that bacterial slimes and fouling chloroorganics identified by Jolley chloroform and other organisms like mussels that reduce killed at least half of the test trihalomethanes were present in the efficiency of electricity animals. However, these drinking water throughout the generation. Jolley collected samples concentrations were at least 1000 nation. This finding was cause for from the once-through cooling times as high as the measured concern because chloroform at high systems at the Kingston Steam average concentrations of the level is known to cause cancer in Plant on the Clinch River and chloroorganics released from power animals. Memphis's Allen Steam Plant on plants. the Mississippi River and from Because of reports that Cooling Water Studies cooling towers at ORNL's High excessive releases of chlorinated Meanwhile, back in Oak Ridge, Flux Isotope Reactor and the Oak effluent to waterways may have Jolley teamed up with Carl Gehrs Ridge Gaseous Diffusion Plant. killed fish and because of concern of ORNL's Environmental Sciences Using radio-tagging techniques, he about potentially carcinogenic and Division (ESD) to examine the identified more than a dozen mutagenic chlorinated organic

NUMBER FOUR 1984 45 oo •

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2 80 /J& l OF WATTS BA R LAKE WATER CONCENTIIIATEO 1500X • - ·- - 254 nm 280.-. l OF WA TTS BAR LAKE WA TER CHLORI NATED IN L ABORATORY f APPRO X 1. 4 mo /lil • r CO MBINED CH LORINE RESIDUAL ,ORTHOTOL I OI NE) CONCENTRATE D 15 00X, {::-:-:-::~·i~ n~TIVITY

Chlorir&Gted cooling water from Watt• international conferences on water Bar Lake ezamined by Jolky and hia dilution is extremely rapid. The aaaociotea waa found to have chlorine­ time-concentration curve developed chlorination-held in 1977 in containing organic• and eonatituenta that in this paper was accepted in 1978 Gatlinburg; in 1979 in Colorado abaorb ultraviolet light. At ORNL more by EPA's Region 5 as the method Springs, Colorado; in 1981 at the than 50 chloroorganica were aeparated for determining acceptable chlorine Asilomar Conference Center in from the chlorir&Gted water uaing high­ reaolution ion ezchange chromatography. discharge limits. Pacific Grove, California; and in Several of the eonatituenta were June 1984 at the College of William identified aa chlorophenola, Drinking Water Problem and Mary in Williamsburg, chloropurinea, and chloropyrimidinea. In 1975 when the EPA survey of Virginia. (The number of chlorinated drinking water was participants in these conferences chemicals in drinking water, EPA under way, Jolley and Gehrs grew from 170 in 1975 to 320 in supported studies at ORNL and conceived the idea of organizing an 1979 and 225 in 1984.) In addition, elsewhere to determine the international conference, "Water Jolley edited and published environmental effects of Chlorination: Environmental proceedings for all five conferences, chlorinating cooling waters and Impacts and Health Effects." They with assistance for the past two methods of reducing these effects. wrote to people who had published from Vivian Jacobs of the ORNL In 1977 Jack Mattice, then of ESD, in the field and invited them to the Information Division. and Bud Zittel of the Energy conference, which was held that fall From his work with conferees Division coauthored a paper stating at ORNL. Several talks dealt with and the proceedings, Jolley is much that toxicity to water organisms organics in drinking water and aware of the concern over depends on the concentration of possible health effects. One paper, chlorinated organics in drinking chlorine over time. In this work, by Al Stevens of the EPA water. In the late 1970s he sampled they proposed a model designed to Cincinnati office, pinpointed the some drinking water in Oak Ridge help power plant operators achieve precursors of chloroform and other and found that it contained about safe levels of total chlorine trihalomethanes: humic materials 100 parts per billion (ppb) of residuals. It takes into account formed naturally by the chloroform and other site-specific dilution factors and degradation of plants and aquatic trihalomethanes. "The level of allows higher limits for chlorine life. chlorinated organics in Oak Ridge's discharges (and hence higher Since then, Jolley has been the drinking water then was about the chlorination levels) in cases where driving force behind four other same as the average for the

46 OAK RIDGE NATIONAL LABORATORY Review Dan Kearney (left) and W"llliame check the chlorine •forage tanka at the pamp etation on the Clinch River. Water iB chlorinated at the river near Clark Center Recreation Park before being pamped to the treatment plant on top of the hill, where more chlorine iB added. Kearney iB with the Con~traction DiviBion of the Department of Energy'a Oak Ridge Operation~, and Wllliame iB water plant eaperintendent with Rrut Engineering Company.

At Oak Ridge'• water treatment plant, Cumming was interested in with the University of North Hal WUliame adjrute the rate of flow of chlorine into the drinking water. Above 5-chlorouracil because it is an Carolina and now with Oak Ridge are "feeder•, • emall pipe• that add analogue of cytosine, a constituent Associated Universities, presented a chlorine to the water a. it enter• the of DNA. He wanted to test whether paper at the 1984 Water etorage re•ervoir. such an analogue would be Chlorination Conference suggesting incorporated into DNA and possibly that consumption of chlorinated nation," Jolley says. "EPA later set cause mutations (genetic changes). drinking water is significantly a limit of 100 ppb for If such mutations occurred, the associated with colon cancer among trihalomethanes. That posed altered genes would make mutated, older white residents of North problems for cities in places like or foreign, proteins. Cumming fed Carolina. south Florida whose levels of 5-chlorouracil to mice and found Also at the recent Water trihalomethanes approached that they incorporated it into their Chlorination Conference, 300 ppb. They had to use chemical DNA as determined by sperm DNA K. P. Cantor of the National techniques to reduce the organic analysis. But he was unable to Cancer Institute reported that the content of the water." detect any sign of mutations. relative risk of bladder cancer for a In 1977 an ORNL biochemist Says Jolley, "Cumming's finding nonsmoker is higher if the person found evidence that a compound that 5-chlorouracil is incorporated drinks chlorinated surface water detected in drinking water could be into DNA suggests that the instead of nonchlorinated a potential health hazard. Bob compound may have subtle health groundwater. To someone who Cumming of the ORNL Biology effects, and scientists should look drinks the groundwater, the Division (who helped Jolley and for them. And the fact that relative risk is 1.0; to someone who Gehrs organize the first water Craythorn found 5-chlorouracil in drinks the chlorinated surface chlorination conference and who drinking water in Great Britain water, the relative risk rises from helped in the planning of each of suggests scientists should search 1.4 for <20 years of use to 3.1 for the others) became interested in for it in drinking water elsewhere, >60 years of use. Relative risk is the genetic effects of 5-chlorouracil, too." defined as the rate of incidence of a chlorinated organic chemical Have any links been established disease in the exposed population (formed from the chlorination of between incidence of cancer and the divided by the relative risk of uracil, which is excreted in urine). concentration of chlorinated disease in the unexposed. If the First identified in 1973 by Jolley in organics in drinking water? number is greater than 1, the chlorinated wastewater, this According to Jolley, several exposed population has a higher compound was subsequently found scientists have persuasive evidence incidence of disease than the in drinking water in 1978 in Great that such a link exists. Donna unexposed. Britain by Brian Crathorne. Cragle, an epidemiologist formerly In a talk given August 3, 1984,

NUMBER FOUR 1984 47 Sleuthing for Drinking Water Compounds That Impair Thyroid Function

n the 1960s Dr. Eduardo Gaitan, a Colombian nendocrinologist and practicing physician, was perplexed by a medical problem that he saw in many of his patients in western Colombia. He could not understand why so many children suffered from goiter, an enlargement of the thyroid gland that can lead to impaired function of the gland and, at the worst, to lethargy and mental retardation. He noticed that even after nationwide preventive treatment with iodine, the incidence of goiter among his patients remained high. Eventually, his curiosity impelled him to undertake a classic epidemiological study. Dr. Gaitan focused his attention on the Colombian village of Candelaria. His 1964 survey of schoolchildren showed that many had thyroid problems, with 11% of the children in the southern half of the village and 23% in the northern portion having goiter. It occurred to him that an environmental cause might explain why proportionally more children in the northern part than in the southern section had thyroid problems. He began to suspect that

the drinking water of the two groups was different. Thia lZ-year-old Colombion boy 1uu goiter, em enlorgement of When Dr. Gaitan checked the sources of drinking the thyroid that can be seen by inspecting hia neck. water, he learned that the town drew its water from two unchlorinated wells. The water in one well came from an iodine to make thyroid hormones, which control the aquifer surrounded by sedimentary rock, while the water overall metabolic rate in the body. Through interviews in the other originated in an igneous rock formation. The with the children about their health conditions and places differences in the underlying rock suggested to the doctor of residence, he gathered evidence that strongly that water from one well, but not fr

at ORNL, Richard Bull, director of aromatics, alkenes, and alkanes. metabolized." the Toxicology and Microbiology Bull said that at EPA research Is There a Solution? Division at EPA's Health Effects is under way on the potential Research Laboratory in Cincinnati, health effects of not only chlorine Jolley is not alarmed by these said that recent research results but also alternative disinfectants findings on possible health effects indicate that chemicals in such as chlorine dioxide. of chlorinated water. "The risk of chlorinated drinking water that Researchers are identifying the cancer from drinking chlorinated were found to cause mutations in chemical by-products of a given water," he says, "is considerably bacteria or skin and lung tumors in disinfectant, which, he said, depend less than the risk of early death mice are not limited to the volatile on secondary water characteristics, from drinking unchlorinated water. trihalomethanes. Biological activity, such as the pH (acidity level) and If drinking water weren't he said, can also be induced by temperature of the water. "In some chlorinated or otherwise nonvolatile chemicals present in cases," Bull noted, "by-products are disinfected, people would likely water, which include acids, also formed in the intestinal tract become ill or die from diseases aldehydes, ketones, nitriles, after the chemical has been caused by bacterial pathogens. In

48 OAK RIDGE NATIONAL LABORATORY Review interested in pinpointing which chemicals in the Today Dr. Gaitan is a permanent resident of the Candelarian well water caused goiter in the village United States, works as chief of the Endocrinology children. He read the scientific literature to find out who Section of the Veterans Administration Medical Center at had been working on identifying organic compounds the University of Mississippi, and continues to collaborate present in water. He ran across the name of Bob Jolley with Jolley. The doctor now is investigating whether of Oak Ridge National Laboratory. Dr. Gaitan then drinking water in two Kentucky counties is responsible for contacted Efraim Otero-Ruiz, president of the Colombian an unusually high incidence of goiter in children there. He National Science Foundation. In 1976 Otero-Ruiz visited has collected ten water samples that are being analyzed Jolley at ORNL and asked him if he were willing to at ORNL by several different techniques. Funds from the analyze some water samples from Candelaria. Jolley said University of Mississippi are supporting the analyses, yes and thus began his long collaboration with which are being performed by Jolley and Kevin Felker of Dr. Gaitan. About the time that the samples were the Chemical Technology Division; Michelle Buchanan, shipped to Jolley, he received a letter from Dr. Gaitan Cecil Higgins, and Jerry Uhlrich of the Analytical informing him that the doctor was moving to the United Chemistry Division; and Ben Benjamin and Emily Douglas States to take a position at the University of Alabama in of the Chemistry Division. Preliminary results indicate that Birmingham. 2,4-dihydroxy acetophenone, whose structure is similar to Jolley and Jim Thompson of the Chemical Technology that of resorcinol, is present in one sample of Kentucky Division (CTD) analyzed the samples using high-pressure drinking water. liquid chromatography. They found humic materials "The likelihood that goitrogens are present in drinking (decayed organic matter) in the water but did not turn up water may be greater than is commonly realized," Jolley any known goitrogens. Jolley suggested that Dr. Gaitan says. "Leachate from Chattanooga shale is known to be send him more samples of the water, including goitrogenic, and several water supplies in Alabama are concentrates, as well as activated carbon filters used to suspected of containing goitrogens. Also, goiter in remove the organic constituents from the well water. American children is not an uncommon disease. In In 1981 Dr. Gaitan sent Jolley concentrates and filters California, for instance, 7% of the school children have from Candelaria. Jolley froze the samples until he could goiter. ,In U.S. hospitals 1% of all operations are related make time to investigate them. In 1982 he and Norman to thyroid problems. Lee of CTD used different solvents to extract a variety of "If we can establish that drinking water can be linked organic compounds from the filters and concentrates. to many cases of goiter," Jolley adds, "we will have Then they ran the extracts through a CTD gas uncovered a public health problem of worldwide chromatography-mass spectrometry system. In their significance. Such a finding would imply that more analysis of the methylene chloride solvent, they hit the attention should be paid to removing organic materials jackpot: They found evidence of resorcinol, a naturally from water as well as disinfecting it to make it fit to occurring goitrogen known to be extremely potent. drink."

Third World communities where water to form oxidized organics and treating the water. water is untreated, many people aldehydes that are known to cause "In the United States," he adds, 1 succumb to gastrointestinal mutations. But, Jolley observes, "we frequently get our drinking diseases and typhoid fever, and Americans can learn a lesson from water by treating surface water many babies and young children die the Europeans about how to make with chlorine without removing the from diarrheal diseases." treated drinking water as clean and organic material first. Considering Would it be preferable for U.S. safe as possible. the possible health costs of cities to treat their water with "European cities," he says, drinking water laden with organics, ozone as many cities in continental "operate on the principle that water the investment to improve the Europe do? Jolley thinks not, should be of high quality before it drinking water source by using considering the current state of is disinfected and piped to people techniques such as bank filtration knowledge. He says that ozone, an for drinking. The Europeans would be worthwhile. The resulting active chemical compound achieve this quality by using high-quality source water will make consisting of three atoms of oxygen, filtration and other means to the drinking water product cleaner can react with constituents of remove the organic material before and safer for all." 1!!1

NUMBER FOUR 1984 49 Near G pond Gt the et~at end of the ORNL comple%, Dick Ketelle (left) Gnd Francoi8 Pin demorutrote whGt Ketelle CGlla "high-tech WGter witchirag•----uamg GR irutrumerat corui8tirag of G blGek OO%, CGble, Gnd laulG hoop-size coil to determine where groundWGter i8 likely to be loeGted. By tGkirag electriCGl conductivity met~auremerata of the ground below, the two reaeGrehera CGR determine where monitoring wella ahou.ld be plGeed to teat groundWGter quGiity. (See OO% ora PGgea 5Z-53.)

• Graan ler • What Are the Environmental and Legal Problems?

alf of the drinking water in and protection of groundwater and In their introduction, Travis and IHi the United States comes from reclamation of polluted aquifers to Etnier provide several examples of groundwater, which is subsurface ensure that all sources of drinking groundwater pollution and possible water that occurs beneath a water water are clean and safe. contamination of drinking water table in soils or rocks or in geologic The extent of known that aroused public concern: formations called aquifers. Many groundwater pollution, knowledge • A 1975 survey of 80 chlorinated residents who drink water from of health effects, and attempts to water supplies from aquifers wells assume that they are drawing deal with the problem are throughout the United States found pristine, high-quality, unpolluted documented in Groundwater widespread contamination by such water from the earth. PoUution: Environmental and Legal potentially toxic organics as Unfortunately evidence that some Problems, a 1984 American trihalomethanes, carbon tetra­ aquifers have been contaminated by Association for the Advancement of chloride, and 1,2-dichloroethane. synthetic organic chemicals Science Selected Symposium book. • In 1979 a Massachusetts state discharged by industrial and The book, a compilation of papers commission reported that the agricultural operations continues to by five experts on the groundwater drinking water supplies in one­ increase. Some of these chemicals problem, was edited by Curtis third of the state's communities are known to cause cancer and Travis and Elizabeth Etnier. Travis were chemically contaminated and nerve disorders in animals. is editor of the journal Risk that private and public wells were Although the long-term health Analysis and director of the Office closed or restricted in 22 towns. impacts on humans of low-level of Risk Analysis of the Health and • In January 1980, 37 public wells exposure to these chemicals are Safety Research Division of Oak that supplied water to more than unknown, the American public has Ridge National Laboratory; Etnier 400,000 people in 13 cities in the expressed concern. Concerned now works in the Information San Gabriel Valley of California citizens are pressing legislators to Research and Analysis Section of were closed because of enact laws to require monitoring the ORNL Information Division. trichloroethylene contamination.

50 OAK RIDGE NATIONAL LABORATORY Review • Analysis of samples of drinking concentrations above the state's wastes have been discharged to water drawn in 1981 from 1000 limit for 100 to 140 years. surface waters or left exposed to wells in New Jersey showed that Temik® was also banned in rainwater. Runoff from rain and the water contained 56 toxic Florida in 1983 shortly after it was snow melts dissolves chemicals and substances, including 47 chlorinated detected in at least eight wells at seeps into the ground, eventually hydrocarbons and 9 heavy concentrations as high as 315 ppb, finding its way to aquifers. In fact, metals-arsenic, beryllium, 30 times the safety limit (10 ppb) 25% of all precipitation ends up as cadmium, copper, chromium, nickel, recommended for drinking water by groundwater. Chemicals in the lead, selenium, and zinc. the U.S. Environmental Protection surface water enter the sediments Agency (EPA). One reason for the and seep into subsurface areas, Pesticide Pollution ban is concern that three of the eventually ending up in The case of the toxic pesticide state's major potato-growing groundwater. aldicarb (sold under the trade name counties lie above the the Floridian Groundwater can itself pick up Temik®) illustrates the "insidious Aquifer, from which 42% of the contamination by moving into nature of chemical contamination state residents take their drinking underground areas where waste of the nation's drinking water water. chemicals have been buried. The supplies," say Travis and Etnier. How widespread is the problem movement of groundwater is of The pesticide, used to kill insects of groundwater pollution? David E. concern also because that is the and other pests that attack Burmaster, former staff member of route by which contaminated water potatoes, cotton, and sugar beets, is the President's Council on reaches public and private wells. a nerve poison that is fatal to Environmental Quality and now an Groundwater movement ranges humans in high doses. Nevertheless, associate with Industrial from 1 to 500 m/year; thus it can the manufacturer and users of the Economics, Inc., in Cambridge, be detained for only a few years or pesticide believed that its toxic Massachusetts, says that during the for tens of thousands of years. If residues would break down into past ten years synthetic organic the detention time is long, centuries nontoxic chemicals before reaching chemicals have been detected in might pass before a polluted groundwater. drinking water wells in virtually aquifer could flush itself of In August 1979 scientists every state. contaminants. However, as Robert sampled nearly 8000 wells in the The abundance of synthetic Cleary, professor of geoscience at potato-farming area of Long Island, organic chemicals and their the University of Sao Paulo, points where aldicarb was being widely improper disposal in the past out, groundwater flow patterns are used. They found that nearly 30% 25 years are largely responsible for difficult to describe and predict of the sampled wells showed today's groundwater pollution accurately because of the extensive contamination by aldicarb, with problem. Travis and Etnier report fieldwork and digital computer 15% exceeding the New York State that annual production of industrial models required for the task. Health Effects Unclear The health effects of contaminated groundwater are A book edited by two ORNL researchers discusses the implications of poorly understood, according to groundwater pollution caused by human discharges of synthetic Robert Harris, codirector of the chemicals. ORNL scientists' attempts to monitor and prevent Hazardous Waste Research deteriorating groundwater quality are explored. Program at Princeton University's Center for Energy and Environmental Studies. One reason is that where human health Department of Health guideline of and agricultural chemicals in the problems of unusual proportions seven parts per billion (ppb). As a United States quadrupled between exist, proving that contaminated result of these findings, Long 1960 and 1980 and that only 10% of drinking water caused them is Island in 1980 banned Temik® for the more than 3.5 X 1010 kg of difficult. agricultural use. The ban will not hazardous chemical wastes Consider the cancer cases of solve the problem entirely: A generated by chemical production Woburn, Massachusetts. In 1979 a Cornell University study estimates are disposed of in an red flag was raised when the that Temik® in Long Island environmentally safe manner. Centers for Disease Control in drinking water could persist at Since 1960 most of the chemical Atlanta learned that six Woburn

NUMBER FOUR 1984 51 Electromagnetic Terrain Conductivity Surveys Tell Where Beat To Monitor Groundwater Quality

Ti))ublic and institutional concern about the failure to In this technique a Geonics EM 34-3 instrument uses .!.rprotect groundwater from contamination and to a 63-cm-diam transmitting coil to generate a primary reclaim polluted aquifers has risen sharply in recent electromagnetic field, which induces current flow in years. At the same time, increasingly sophisticated conductive materials, such as water and dissolved solids, groundwater studies and the associated technology are within the area of influence. A 63-cm receiver coil detects helping researchers and regulators accurately evaluate and measures the secondary electromagnetic field that groundwater quality. However, because the cost of results from the subsurface current flow. performing high-quality studies of groundwater is great, According to Ketelle, • An electromagnetic conductivity investigators must develop techniques that will enable greater than that of a similar 'background' area may strategic placement of monitoring wells and groundwater indicate the presence of more subsurface water, or pore tests. One approach is to use surface geophysical fluid, which can indicate groundwater flow paths; more techniques; they can provide rapid and economic dissolved solids, such as soluble waste materials; or characterization of subsurface conditions and can locate both." the best sites for groundwater testing. The instrument's depth of influence can be varied by ORNL researchers Richard H. Ketelle of the ORNL changing the separation of the coils, which are held Energy Division and Francois G. Pin of the Engineering aboveground at distances of 10, 20, or 40 m apart. The Physics and Mathematics Division have been using a greater the separation, the deeper the measurements. By surface geophysical technique for studies of migration of using different coil separations, multiple depth hazardous wastes into groundwater on the Oak Ridge measurements are made over the same traverse route, Reservation and in Wyoming. The technique, called yielding a three-dimensional map of conductivity. electromagnetic terrain conductivity mapping, has been used for many years as a mineral prospecting tool. The ~ he ORNL scientists used the technique to map mapping technique uses special equipment, including two lJ. potential groundwater flow paths in a portion of the coils, to measure the apparent electrical conductivity of proposed Central Waste Disposal Facility site on West subsurface materials over varying depths, from near the Chestnut Ridge. With the technique they characterized surface to depths exceeding 50 m. flow paths controlled by dissolution of the dolomite

children living in a six-block area between exposure to these Pollution Solutions? had developed leukemia. This substances and childhood finding triggered a study of cancer leukemia." Is there a technical fix for mortality in Woburn, which showed Harris says there is generally groundwater pollution? David that the town had a death rate insufficient information to link Miller, author of Report to Congress higher than the national average public health impacts to chemical on Waste Disposal Practices and for leukemia and kidney cancer. contamination of groundwater. The Their Effects on Groundwater, The culprit for the excess cancers Office of Technology Assessment argues that the best protection for was believed to be toxic waste (headed by Jack Gibbons, formerly groundwater is to prevent it from disposal sites containing hide­ of ORNL) reports that 3 million ever becoming contaminated. This tanning chemicals and pesticides chemical compounds are used in the protection can be ensured only by produced in Woburn between 1850 United States and that 3000 new banning disposal of toxic wastes and 1920. Researchers in 1979 had chemicals are added each year. near aquifers whose waters are still found no evidence that cancer Unfortunately health-effects data pristine. Miller says that measures victims were exposed to toxic exists for only a small number of exist to treat groundwater to substances in drinking water at chemicals, and most of this data reduce its concentration of chemical levels high enough to cause cancer. comes from animal studies. contaminants and to help it recover However, according to Travis, "A "Despite these problems," says from the intrusion of hazardous recent study by the Harvard School Travis, "several very recent studies wastes. Remedial actions include of Public Health has found a indicate that organics in drinking pumping the water from the positive statistical association water may be a ticking time bomb." aquifer over a 25-year period,

52 OAK RIDGE NATIONAL LABORATORY Review bedrock. Groundwater tends to flow through areas of the of their electromagnetic mapping correlated well with dolomite where it has created cavities by dissolving the measurements of electrical conductivity (specific rock, forming beds of wet clay (which are more conductance) in groundwater taken from wells in the conductive than solid bedrock). Performance of a study area. Ketelle and Pin's results were used in fluorescein dye tracer test in the same area confirmed planning the layout of treatment facilities for use in the general flow path, indicated by the electromagnetic closeout activities at the 8-3 ponds to minimize conductivity study. This information was used in the disturbance of soils in the plume area. pathways analysis for the site and helped the ORNL Ketelle and other ORNL staff members are using the researchers identify the best areas for locating electromagnetic method at selected uranium mill tailings groundwater monitoring devices. management areas in Wyoming for the Uranium Recovery Because terrain conductivity may be strongly Field Office of the U.S. Nuclear Regulatory Commission influenced by the electrical conductivity of pore fluids, the (NRC). They are demonstrating the effectiveness of this technique is useful for locating seepage plumes containing technique for NRC, which may use it to monitor seepage electrolytic fluids, such as acids, which are found in some of fluids out of tailings ponds. The terrain conductivity hazardous wastes. The ORNL researchers mapped the surveys are being correlated with groundwater pH migration of electrolytic fluids in the vicinity of the 8-3 (acidity level), specific conductance, and available ponds at the Oak Ridge Y-12 Plant, using the technique subsurface data. in conjunction with a preliminary evaluation of the "Electromagnetic terrain conductivity is just one of hydrogeology of Bear Creek Valley. many surface geophysical techniques available," says Infiltrating fluids are known to travel through fractures Ketelle. "It has broad applicability in groundwater studies, and bedding planes in weathered shale bedrock. Ketelle as we've shown by a variety of applications in various and Pin's terrain mapping confirmed that the shale geological settings. Now, we hope to refine our bedrock structure in Bear Creek Valley controls the interpretive methods and depth resolution to further direction of the migrating fluids. They also found that the enhance the technique's versatility. It could be used by elongated plume parallels the geologic strike, or outcrop industry and regulators to select the best sites for trend-that is, the compass orientation of the bedrock monitoring groundwater quality." controls the flow path of the seepage plume. The results

detoxifying it, and reinjecting it classifying aquifers according to concentrations of a few parts per into the ground. However, he adds, whether they have (1) pristine, billion-groundwater can no longer these measures are rarely unpolluted water, (2) contaminated be used for drinking water, unless completely successful. water that can be made potable expensive treatment methods are Because of growing public and with reasonable treatment, or installed. congressional concern over (3) water so contaminated and so "Some former drinking water groundwater pollution, EPA in 1982 isolated that it is unusable. supplies are so contaminated now proposed a national groundwater Following classification, Tripp says, that they may never be used again : policy. This policy would give state land use restrictions should be for many generations-if ever. and local governments a lead role imposed to prevent contamination These hydrologic and biological in developing and implementing of pristine or potentially potable realities are quite sobering. Having means of protecting groundwater. sources and to permit waste spent several years now Classifying groundwaters by disposal only near unusable understanding the intricacies of quality is "the first step in groundwater sources. groundwater management, I am establishing any groundwater "Groundwater," concludes glad to paraphrase the saw, 'An quality program," says James T. B. Burmaster, "is easily contaminated, ounce of prevention is worth a tan Tripp, counsel for the especially by certain volatile of cure.'" - Carolyn Krause. Ill Environmental Defense Fund organic chemicals which readily (EDF) and director of EDF's penetrate the normal protective Eastern Water Resources and Land mechanisms. Once contaminated by Use Program. Tripp recommends organic chemicals-even in

NUMBER FOUR 1984 53 Diverting Groundwater from Burled Racloactlve Waste

~ hallow land burial of low-level seal may be faulty. Another possibility is original grade by backfilling with site ~ radioactive waste in the eastern that subsurface flow from outside the soil. No drainage pipe was placed in the United States was considered a safe sealed area is contributing to water in bottom of the excavation. practice for more than three decades. the trenches." Except for the five days spent However, in the mid-1970s a potential excavating sidewall material that slid problem was found to exist: Moving ~ oncerned about the possible into the drain during construction, the groundwater could come in contact with ~ intrusion of water from below the project proceeded smoothly. In late the buried waste, leach radionuclides, surface, ORNL researchers, led by September 1983 the excavation and transport them to unrestricted, off­ Davis and R. G. Stansfield of ESD along equipment was removed from the site, site areas where they might eventually with W. D. Barton of the Engineering and construction began on the two jeopardize private and public water Division, considered several engineered concrete catch basins used to receive supplies. Water enters waste trenches barriers that could intercept shallow flow from the two drain sections. In either by the upward flow of subsurface flow and suppress the October the catch basins were groundwater as the water table rises fluctuating water table within the completed, and the site was seeded following a period of heavy precipitation, 49-trench area. These options included and returned to nearly original by lateral subsurface flow of surrounding the site with rock-filled conditions. groundwater, or by direct surface caissons, a slurry wall anchored to To evaluate the effectiveness of the infiltration from rainfall and snow melts. bedrock, a drilled pier cutoff wall, or a French drain in SWSA No. 6 during the One institution with a direct interest passive French drain. They selected the wet winter months, Davis and Stansfield in this problem is Oak Ridge National French drain, which is a trench lined compared the water table elevation Laboratory, where low-level radioactive with filter fabric, backfilled with crushed records in the 49-trench area for wastes have been sequestered in stone, and covered to the original February 1983 (before drain trenches in six solid waste storage surface level with the excavated soil. construction) with those for February areas (SWSAs). Water has been found Their decision was based on total 1984 (after construction). Says Davis: to enter and collect in waste trenches at design and construction costs, ease of "We found a significant postconstruction ORNL. In 1976, for example, shortly installation, and probability of success. drop in the water table level, bringing it after the 49-trench area in SWSA No. 6 The design goals of the drainage generally below the lowest portion of was closed, Harpal Arora, Dale Huff, project were to ( 1) intercept and divert the buried waste." and Dave Ward of the ORNL subsurface flow from uphill slopes Davis also says that "the water Environmental Sciences Division (ESD) before it can enter the waste trenches table level was drawn down toward the noted that many trenches were holding and (2) lower the water table within the drain bottom in an area extending about water much like bathtubs, particularly 49-trench area and keep it suppressed 60 m into the 49-trench area. The site during the wet winter and spring during the wet months of the year so water table no longer mimics the months. In an attempt to prevent that the groundwater is too low to flow surface topography; instead, it slopes rainwater from infiltrating the cover laterally into the waste area. Over a toward the bottom of the drain. As a material and collecting in the trenches 40-day period starting in August 1983, result, the water table has been lowered after each rainstorm, workers installed a a French drain 252 m long, 1 m wide, about 4 m in the northeast comer of the bentonite clay cover in the fall of 1976 and 9 m deep was constructed at a site, where the two drains intersect. to seal the entire 0.44-ha (11-acre) cost of $153,000. The topography of This achievement will be useful in the trench area. This sealing operation was the site required construction of the design construction of other drains in expected to result in a gradual draining drain in two sections, which intersect in similar geologic media." of water from the underlying trenches. the northeast corner of the site at a Despite this attempt, water depth of 9 m below the ground surface. ~ he French drain is considered continues to collect in the underlying As the design depth of the drain .!.1 successful in protecting the trenches at depths fluctuating between was reached, filter fabric made of radioactive waste in the 49-trench area 1 and 2 m. The maximum water level nonwoven celanese with openings of up if it suppresses the water table to a occurs in January, February, and to 0.015 em was placed on the depth of at least 4.9 m. At this depth March; the minimum, in September and sidewalls, and crushed stone was the water table will no longer intersect October. Says Ed Davis of ESD: "The poured into the lined excavation to the bottoms of the waste disposal seal may be keeping out direct within 0.6 m of the surface. Next, the trenches and cause periodic trench infiltration of rainfall. But after eight filter fabric was folded over the crushed inundation and possible radionuclide years, water levels in the trenches still stone fill-material, and the remaining migration. fluctuate seasonally, suggesting that the 0.6 m of trench was brought to the According to Davis, "We found from

54 OAK RIDGE NATIONAL LABORATORY Review A view of the •olid UIG8te •toroge area (SWSA) No. 6 French drain dwing eoMtn&ctiora. The 1-m wide esCGvation i8 lined with filter fabm, bGcltfilled with cnuhed .tone, GAd covered to origiRGli{Tade with esCGVGted •oil. The drain UIG8 fou.nd to protect lur.lf of the bu.riGl •ite for low-level radioGctive UIG8te (GAd Z9 of 49 trenche•) · from contGct with ming groiJ.ndWGter. ..,. CATCH BASIN N0. 1 (" ---..,./..,.

0 '"

0 ""

40•1 395 e DEPTH TO WATER ~ 4 .9 m

CATCH APPROXIMATELY 50% OF THE 49-TRENCH AREA BASIN HAS A SUPPRESSED GROUNDWATER TABLE NO.2 proximity to the drain. "No other PlGn view of the SWSA No. 6 French trenches in the area dried up so drain •howing the estent of grou.ndWGter •u.ppre••ion. The drain UIG8 completed our water elevation survey that the drain dramatically," says Davis. "In fact, lGte in 1983. A• a re•u.lt of thi8 drain. 5 of suppressed the water table in half of many continued to show a pattern of the 49 trenche• I&Gve dried ou.t GAd Z4 the 49-trench area through the winter of rising intratrench water levels during other• are no longer target• for intru.ding 1984. Thus 29 of the 49 waste disposal November and December 1983 and grou.ndWGter and for •u.rface WtJter trenches were protected from contact January 1984 after drain construction. percolGting into the grou.nd. with rising groundwater. We also found This postconstruction rise in intratrench that monitoring wells more than 60 m water levels suggests that the bentonite at waste disposal sites. "If the surface away from the center of the drain have clay seal is leaking and that the water topography is suitable, a drain can not been affected by the drain's is entering the trenches as surface discharge to surface water at a lower drawdown. They continue to show infiltration, not as rising groundwater or altitude than the area being protected water at less than 4.9 m after rainfall.~ lateral subsurface flow. We've and thus require no future operation and From analyses of the data, Davis concluded that the entire bentonite clay maintenance costs," Davis says. "The and Stansfield also identified five waste sealing procedure should be concept of subsurface drainage as trenches that were completely drained reevaluated." demonstrated by this project is actually of intratrench water as a result of the The SWSA No.6 drainage project quite simple, but it could be applied to drain's construction. They attribute the has demonstrated that a French drain various water-related problems at waste drying of these trenches to their close can help control water table fluctuations disposal sites throughout the nation.~

NUMBER FOUR 1984 55 awards and appointments

James 0. Stiegler has been Competition for developing lead­ of the National Research Council's appointed director of the ORNL iron phosphate glass to store high­ Commission on Behavioral and Metals and Ceramics Division. level nuclear wastes. For their work Social Sciences and Education. James R. Weir, Jr., has been in developing ductile nickel named associate director of the aluminides for high-temperature John G. Merkle has received the division. structural use, Chain T. Liu, George R. Irwin Medal for 1984 Joseph A. Horton, and Calvin L. from the American Society for Christine Travaglini has been White also received an award in Testing and Materials. The award named director of the ORNL this competition. Both is given annually to an individual Finance and Materials Division. developments were cited for their who has made original She is the first woman to be "significant implication for energy contributions in the field of appointed division director at technology." fracture mechanics whose ORNL. applications lead to improved safety Martin S. Lubell has been Robert J. Gray has been named of structures. appointed to the International the 1984 recipient of the Albert Organizing Committee for the Sauveur Achievement Award from Curtis C. Travis, editor-in-chief of Magnet Technology Conferences. the American Society for Metals. the journal Risk Analysis, has been This committee has 16 members, He was honored for his "pioneering appointed coordinator for the who represent the major technology metallurgical achievements." ORNL Office of Risk Analysis. nations, including East Bloc countries and the Peoples Republic David L. Greene and Patricia S. Lee Berry has been appointed of China. Lubell is one of two Hu have received the Pyke Johnson associate division director for members from the United States. Award of the National Research Development and Technology in the Council's Transportation Research ORNL Fusion Energy Division. He Jagdish Narayan has been named Board for their paper "Vehicle is also manager of the ORNL a Fellow of the American Usage in Multi-Vehicle Households Fusion Energy Development and Association for the Advancement of and the Price of Gasoline." This Technology Program. Science. award is given each year for the best paper in the area of planning Michael J. Saltmarsh has been Stan A. David and Chain T. Liu and administration of named head of a newly created have been named Fellows of the transportation facilities. Confinement Projects Section in the American Society for Metals. David ORNL Fusion Energy Division. was recognized for "contributions to David E. Bartine has been understanding of solidification appointed manager of ORNL's new William R. Laing has been behavior and microstructural Strategic Defense Initiatives ("Star awarded a certificate of characteristics of welds, peritectics, Wars") Program. appreciation by the American and composites." Liu was cited for Society for Testing and Materials "contributions to understanding James W. Terry has been for editorial excellence in the materials behavior in the solid appointed manager of institutional preparation of standards. state, particularly with precious planning for ORNL. William H. metals, and recognition of the Butler has been named manager for James B. Roberto has been importance of electron-to-atom computer planning at ORNL. Both appointed technical assistant to ratio in production of ductile long­ are members of the ORNL Program Alex Zucker, Associate Director for range ordered alloys." Planning and Analysis Office. Physical Sciences at ORNL.

Brian C. Sales and Lynn A. Eric Hirst has been appointed a Peter Lalley has left ORNL to Boatner received an award in the member of the Committee on become director of the Institute for Department of Energy's 1984 Behavioral and Social Aspects of Medical Research in Bennington, Materials Science Research Energy Consumption, a committee Vermont.

56 OAK RIDGE NATIONAL LABORATORY Review readers comment

To the editor:

Betrayers of the Truth, by William Broad and Nicholas Angell goes on: "Perhaps the most serious error in Wade, was reviewed rather favorably in issue the depiction of science . . . is the implication that Number Two of the 1984 Review. The book was less scientists do not take into account the possibility of self­ favorably reviewed for Science in its March 25, 1983, deception. This is not so." Broad and Wade decry the issue (pp. 1417-18) by Marcia Angell, deputy editor of impersonal format of the scientific report as a sort of the highly respected New England Journal of Medicine. public relations trick ("to give the appearance of Her criticisms bear repeating here. She points out that objectivity," they say). Angell points out that one reason the same charge that Broad and Wade level at for that format is "to require the researcher to confront scientists-namely, falsification of data-can be leveled his or her data," as Broad and Wade should know. at these authors, thus undermining or invalidating their Broad and Wade see the responses of the scientific principal thesis. community as inadequate, which Angell concedes. "How frequent is fraud in science?" asks Angell. However, she points out that "their tone of outrage is "After considering the scanty evidence on the subject, inappropriate and does not allow for the complexities and Broad and Wade conclude, 'We would expect that for uncertainties of dealing with a situation as it unfolds, every case of major fraud that comes to light, a hundred rather than in hindsight. ... [Also, there are] or so go undetected. For each major fraud, perhaps a uncertainties about due process and the legal thousand minor fakeries are perpetrated.'" Angell ramifications of making an accusation of fraud." comments, "No basis for these numbers is given. This She concludes, "It would be a pity if the scientific sort of calculation by expectation [italics mine] is community allowed the misconceptions [and, I might add, surprising in such stern critics." the exaggerated 'evidence'] in [this] book to deflect it Broad and Wade have done exactly what they from the important point that we must take fraud attempt to lay on the scientific community: enlarged their seriously and continue our efforts to develop methods for data by factors of 100 or 1000 at the stroke of a pen! dealing with it effectively." Just who is betraying the truth? Waldo E. Cohn, senior biochemist, retired Consultant in Biology Division. OAK RIDGE NATIONAL LABORATORY REVIEW U.S. Postage P.O. Box X, Oak Ridge, Tennessee 37831 PAID BULK RATE Oak Ridge, Tenn. Perm it No.3

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