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4 Research Programs in Other Agencies of Government As part of its task to formulate recommendations for a long-term research program to address the U.S. Department of Energy's (DOE's) subsurface contamination problems, the committee was asked to con- sider research already completed or in progress by other federal and state agencies and to identify areas where the Environmental Manage- ment (EM) Science Program could make significant contributions (see Sidebar 1 .1~. The committee partially addressed this task in Chapter 3 by reviewing research that was completed or underway in the program itself. In this chapter, this task is completed by examining research pro- grams in other agencies of government. The committee gathered information for this review from a variety of sources. The committee received briefings on research programs in five federal agencies at its fourth information-gathering meeting (see Appen- dix B): Department of Defense (DOD), DOE, Environmental Protection Agency (EPA), National Science Foundation (NSF), and the U.S. Geo- logical Survey (USGS). The purpose of these briefings was to provide an overview of the research programs and to give the committee an oppor- tunity to assess how well these programs were being coordinated. The committee then conducted additional research on these and other pro- grams through electronic searches,2 followed by contacts with selected program managers. The committee's initial plan was to summarize the information on other research programs using the organizing scheme shown in Figure ~AIthough the statement of task explicitly directs the committee to examine research in "other federal" agencies, the committee has interpreted its mandate to include research in other parts of DOE, especially the Office of Science. 2Searches were conducted using the Internet, specifically research databases such as the Federal Information Exchange at http://web.fie.com/fedix/. C h a p t e r 4 59

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3.2, which depicts the Subsurface Contaminants Focus Area's approach to organizing its technology development programs. However, it quick- Iy became clear that such an approach was impractical. In general, the committee found that most other research programs could not neatly be categorized into one or two of the boxes shown in Figure 3.2. In fact, many of the research programs were quite broad in scope, and it was not possible to obtain an accurate picture of the research being spon- sored without a detailed review of project portfolios, much like the committee provided in Chapter 3 for the EM Science Program. There simply was not enough time available in this study to do that kind of review for all of the programs discussed in this chapter. The committee was surprised by the large number of programs that deal either directly or indirectly with subsurface contamination research. Indeed, the committee identified almost 50 programs that could be related at least indirectly to the work of the EM Science Program, not including the programs on health and health effects spon- sored by the National Institutes of Health.3 Thus, to address its task statement, the committee decided to summarize the scope and objec- tives of these related research programs and to use these descriptions to formu late recommendations for the EM Science Program. The description of these related research programs is provided in Table 4.1 (located at the end of this chapter), which groups them by agency, and then by program within each agency. The table provides a short description of program scope and objectives;4 recent funding levels if available;5 a notation showing whether the program provides intra- mural or extramural funding;6 and a web address (if available) where additional information can be obtained. The programs in Table 4.1 are 3The committee decided to exclude health-related research programs mainly because health research has not been an important component of the EM Science Program. However, the program did focus part of its fiscal year 1999 program com- petition on low-dose radiation, in cooperation with the DOE-Office of Science's Low Dose Radiation Research Program. This competition was completed while the committee'sreportwasinreview.Theresultsfromtheseandotherrelatedresearch programs may have a significant impact on DOE's cleanup program, specifically in establishing the adequacy of DOE's cleanup and containment efforts. 4Program information was derived from descriptions provided by the agencies in their program announcements or at their web sites. 5Funding amounts are for the entire research programs; only a fraction of the amount listed may be for support of subsurface contamination projects. In most cases it was not possible to separate the subsurface research component. 6That is, funding for research conducted within the agency by agency investiga- tors (intramural funding), or funding for research conducted outside of the agency (extramural funding). Extramural funding is typically provided to investigators in academia, national laboratories, industry, or other federal agencies through grants, contracts, and cooperative agreements. S U B S U R F A C E S C ~ E N C E 60

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for federal agencies only; the committee was unable to find any signifi- cant state-funded basic research programs.7 The remainder of this chapter consists of three sections. In the first section, the committee provides a brief review of those research pro- grams that appear to be closely related in terms of scope and objectives to the EM Science Program. The second section provides a short discus- sion of other programs, and the final section provides some concluding observations. Closely Related Research Programs The committee's selection of a research program as closely related to the EM Science Program is based on two somewhat qualitative crite- ria: (1 ) the degree to which the program sponsors basic research, as compared to other activities like technology development; and (2) the degree to which the program sponsors research that addresses the top- ics shown in Figure 3.2. The committee included those programs that it judged had a good match with both criteria. Of the programs shown in Table 4.1, the committee judges that the following 18 programs in eight federal agencies are closely related in terms of scope and objectives to the EM Science Program: U.S. Department of Agriculture. The Environmental Chemistry Laboratory sponsors intramural and cooperative research on phytoremediation and accelerated microbial degradation of organic compounds and has an annual budget of about $2 million.8 U.S. Department of Defense. The Army's Terrestrial Science Program sponsors extramural research on experimental, theoreti- cal, and numerical studies on fluid flow and contaminant trans- port processes in heterogeneous porous media. It has an annual budget of about $1 mil lion. The Naval Research Laboratory sponsors research on in situ remediation, microbial degradation processes, and environmen- tal monitoring. The Strategic Environmental Research and Development 7The committee recognizes that individual states may provide research funding to state agencies and universities for environmental-related basic research, but the committee was unable to identify any state programs that provide state taxpayer dollars at the levels commensurate with the federal agencies listed in Table 4.1. Unless otherwise noted, the budget numbers given in this chapter are for fiscal year 1 999. C h a p t e r 4 61

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. . . Program sponsors extramural research on cleanup, compliance, conservation, and pollution prevention. The program is managed in cooperation with DOE and the EPA and has an annual budget of $59.4 mi 11 ion. About $1 8.4 mi 11 ion of this budget is directed to cleanup-related research. U.S. Department of Energy. In DOE's Office of Science, there are several programs in basic energy sciences that sponsor extramur- al research to understand fundamental physical, chemical, bio- logical, and geological processes (see Table 4.1~. Some research sponsored by these programs is relevant to environmental cleanup, but none is focused explicitly on the topical areas shown in Figure 3.2. There appear, however, to be at least two programs in the Office of Science that are directly relevant to the EM Science Program. The Office of Biological and Environmental Research's Natural and Accelerated Bioremediation Program sponsors extramural research to understand and apply natural processes to accelerate the biologically enhanced immobiliza- tion or degradation of contaminated soil and groundwater. In DOE's Office of Environmental Management, the Office of Science and Technology supports a number of applied research, technology development, and technology deployment programs. The overall objective of these programs is to bring new and improved technologies to bear on cleanup of the DOE complex. DOE also supports numerous user facilities at several national laboratories (see Table 4.2~. Many of these support environmen- tal-related research funded by DOE and other research programs. U.S. Department of Interior. The U.S. Geological Survey's Toxic Substances Hydrology Program funds intramural research on point source contamination in the environment. This program has sponsored 10 field sites around the country (see Sidebar 4.1 ) to encourage collaborative research among USGS and outside scientists on problems ranging from landfill leachates to mine tailings waste. The use of field sites encourages research collabo- rations and spreads the costs of expensive monitoring and other observational facilities. The program has an annual budget of about $10 million, and the field sites themselves are made avail- able at no cost to scientists outside the USGS. These scientists must obtain additional funding from their organizations or from other research programs to support the costs of their research projects. U.S. Environmenta/ Protection Agency. The Office of Research and Development finances a large number of research programs that are directly relevant to the EM Science Program. Almost all these programs are addressing problems of hazardous waste S U B S U R F A C E S C ~ E N C E 62

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Table 4.2 U.S. Department of Energy User Facilities Maintained by Basic Energy Sciences, Division of Materials Sciences Advanced Light Source, Lawrence Berkeley National Laboratory Advanced Photon Source,Argonne National Laboratory Intense Pulsed Neutron Source,Argonne National Laboratory National Synchrotron Light Source, Brookhaven National Laboratory Los Alamos Neutron Scattering Center High Flux Isotope Reactor,Oak Ridge National Laboratory Stanford Synchrotron Radiation Laboratory, Stanford Linear Accelerator Center High Flux Beam Reactor, Brookhaven National Laboratory Materials Preparation Center,Ames Laboratory Electron Microscopy Center, Argonne National Laboratory Center for Microanalysis, University of Illinois National Center for Electron Microscopy, Lawrence Berkeley National Laboratory Shared Research Equipment Program,Oak Ridge National Laboratory Surface Modification and Characterization Research Center, Oak Ridge National Laboratory Combustion Research Facility,Sandia National Laboratory,Livermore,California Maintained by Basic Energy Sciences, Division of Chemical Sciences National Synchrotron Light Source, Brookhaven National Laboratory High Flux Isotope Reactor,Oak Ridge National Laboratory Radiochemical Engineering Development Center,Oak Ridge National Laboratory Combustion Research Facility,Sandia National Laboratories,Livermore,California Stanford Synchrotron Radiation Laboratory,Stanford University Maintained by the Office of Biological and Environmental Research The Atmospheric Radiation Measurement Observation Sites (Southern Great Plains,Tropical Western Pacific, and the North Slope of Alaska) Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory Production Sequencing Facility,Joint Genome Institute, University of California Mouse Genetics Research Facility, Oak Ridge National Laboratory Office of Biological and Environmental Research conducts research at the following user facilities Advanced Light Source, Protein Crystallography Program, Lawrence Berkeley National Laboratory Advanced Light Source, Soft X-ray Spectroscopy Program, Lawrence Berkeley National Laboratory Brookhaven High Flux Beam Reactor (neutron crystallography and scattering), Brookhaven National Laboratory Los Alamos Neutron Science Center (protein crystallography with neutrons), Los Alamos National Laboratory National Synchrotron Light Source (X-ray crystallography of biological macromolecules and UV spectroscopy), Brookhaven National Laboratory Oak Ridge High Flux Isotope Reactor (neutron crystallography), Oak Ridge National Laboratory Stanford Synchrotron Radiation Laboratory (crystallography,spectroscopy,and small-angle scattering of biological molecules), Stanford University Structural Biology Center (crystallography of biological macromolecules), Argonne National Laboratory C h a p t e r 4 63

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management and cleanup in the nation's civilian sector. The National Exposure Research Laboratory, in Research Triangle Park, North Carolina, sponsors research to improve capabilities to locate, characterize, and remediate volatile organic com- pounds, including dense non-aqueous phase liquids, in subsur- face environments. The annual budget is about $3.8 million. The National Risk Management Research Laboratory, in Cincinnati, Ohio, sponsors intramural research on contaminated groundwater and sol I and on containment systems. The ground- water research program focuses on source characterization, remediation, and modeling of organic compounds and such met- als as arsenic. The annual budget is about $4.2 million. The soil research program covers in situ remediation, including biotreat- ment, of persistent organic and metal (lead and cadmium) conta- minants in soils, sediments, and unsaturated subsurface environ- ments. The annual program budget is about $5.6 million. The SIDEBAR 4.1 LONG-TERM RESEARCH SITES The U.S. Geological Survey (USGS) maintains a number of long-term research sites for the study of point source contaminants in the environment.The sites serve as natural laboratories at which scien- tists conduct experiments and long-term observation.They have proven to be ideal settings for the development of scientific knowledge about the fate and transport of contaminants. Examples of sites and contaminants studied include tritium from a low-level radioactive waste disposal site in Nevada; sewage effluent from ponds in Massachusetts; oil from a petroleum pipeline break in Minnesota; oxygenated gasoline from buried tanks in South Carolina; creosote effluent from a cre- osote facility in Florida; mining tailings pond leachate in Arizona; leachate from a landfill in Oklahoma; and organic contaminants from an arsenal in New Jersey. An uncontaminated site in New Hampshire was established to study fracture flow. Some of these sites have been in existence for over a decade. Work at several of the sites was curtailed when scientific interest was satisfied. Each site is managed by a USGS field scientist who lives and works nearby.This person is responsible for maintaining a stable research site by maintaining good working relations with the land owner, scheduling field research, facilitating the research by helping to provide the technical infrastructure, ensuring that research projects do not interfere with one another, and maintaining the site data base. A USGS research coordinator is assigned to work with the site manager and to serve as the link between the site and the research community. Knowledgeable about the site environment and the par- ticular contaminant, the coordinator is responsible for making the existence of the site known in the appropriate research communities and to assist the site manager in coordinating science at the site. The sites have provided fertile environments for scientific study.The prospects of a long-term site with stable scientific management, field assistance, and a long-term database have attracted top scientists in multiple disciplines from academia, government, and the private sector. S U B S U R F A C E S C ~ E N C E 64

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containment research program aims to develop new materials and methods for containment of contaminated groundwater and soil; the annual budget is about $1.9 million. The National Center for Environmental Research and Quality Assurance in Washington, D.C., sponsors five hazardous substance research centers in cooperation with universities across the United States. These centers were established under the Comprehensive Environmental Response, Compensation, and Liability Act (the Superfund Act), and their primary funding comes from the EPA (about $8.9 million in fiscal year 1999), with additional funding from other federal agencies, universities, state agencies, and the private sector. These centers have research foci that are related directly to the EM Science Program: The Great Lakes/Mid-Atlantic Center sponsors research on remediation of hazardous organic compounds found in soils and groundwater. The University of Michigan leads the three- institution consortium. The Great Plains/Rocky Mountain Center sponsors research on soils and mining wastes contaminated with organic chem- icals and heavy metals. Kansas State University leads a four- teen-institution consortium. 3. The South/Southwest Center sponsors research on in situ detection, mobilization, and remediation of contaminated sediments. Louisiana State University leads the three-institu- tion consortium. 4. The Western Center sponsors research on groundwater cleanup and site remediation for organic solvents, hydrocar- bons and derivatives, and heavy metals. The center is a coop- erative activity involving Oregon State University and Stanford U n iversity. 5. The Gulf Coast Center sponsors research on hazardous sub- stance response and waste management. The center is a cooperative activity involving eight universities. The National Center for Environmental Research and Quality Assurance, in collaboration with DOE, the Office of Naval Research, and NSF, also sponsors a program in bioremediation that seeks to understand the chemical, physical, and biological processes that influence the bioavailability and release of chemi- cals in soil, sediments, and groundwater. The annual funding for this program is about $1 million. C h a p t e r 4 65

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U.S. Department of Health and Human Services. The National Institute of Environmental Health Sciences sponsors a joint pro- gram with the EPA on the Superfund Hazardous Substances Basic Research Program, which has an annual budget of about $37 million.This program supports research to understand haz- ardous waste exposure risks and to support the development of site remediation technologies. Nationa/ Science Foundation. Like DOE's Office of Science, the NSF sponsors several extramural research programs to under- stand fundamental physical, chemical, biological, and geological processes (see Table 4.1~. Some of these programs sponsor research that is directly relevant to environmental cleanup, but none is focused explicitly on the topical areas shown in Figure 3.2. There are at least two programs in the NSF that appear to be directly relevant to the EM Science Program. The Civil and Mechanical Systems Program sponsors basic engineering research, including geotechnical research on materials, contain- ment systems, remediation, and modeling. The annual funding for this program is about $59.5 million.9 The NSF also sponsors a cross-directorate program on Environmental Geochemistry and Biogeochemistry, whose goal is to improve fundamental knowl- edge of chemical processes that control the behavior and distrib- ution of inorganic and organic materials in the environment. The annual funding for this program is about $4.8 million. U.S. Nuclear Regulatory Commission. This agency is charged with regulating the production, use, and disposal of radioactive byproduct materials; it sponsors research through the Center for Nuclear Waste Regulatory Analysis in San Antonio, Texas. The Geohydrology and Geochemistry Section in this center sponsors research on surface and subsurface hydrology related to the transport and fate of contaminants. . . Other Research Programs Table 4.1 lists a number of other programs that sponsor research that is less directly relevant to the EM Science Program; nevertheless, these programs support research that may in the long term support the DOE cleanup effort. The basic research programs in DOE's Office of Science and the National Science Foundation, which were mentioned in the last section, are good examples. They sponsor research that will increase 90nly a portion of this total is for geotechnology-related research. S U B S U R F A C E S C ~ E N C E 66

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the basic knowledge pool that can be accessed by the EM Science Program and its researchers. Many of the researchers who receive EM Science Program funding are also being or have been supported by one or more basic research programs in DOE and NSF. There is another group of programs in Table 4.1 that has some rele- vance for the EM Science Program and DOE's overall cleanup efforts, namely, the programs that support risk analysis and risk assessment research. Risk assessment is an important step in the remediation process, as will be shown in Chapter 5, and the EM Science Program is now supporting several projects that address risk-related topics (see Chapter 3~. There are several research programs in Table 4.1 that address various aspects of hazard and risk assessment: The EPA's National Center for Environmental Assessment spon- sors two research programs in this area, one on Superfund health risk assessment, with an annual budget of $2.1 million, and a second on Superfund ecological risk assessment, which has an annual budget of $1 .0 mi l l ion. The EPA's National Center for Environmental Research and Qu al ity Assu rance, i n cooperation with the N ation al I nstitute of Environmental Health Sciences, sponsors a program on complex mixtures that focuses on the mechanistic basis for chemical interactions on biological systems. The annual budget is about $2.7 million. As mentioned in the last section, the National Institute of Environmental Health Sciences sponsors a joint program with EPA on the Superfund hazardous basic research. One of the objectives of this program is to understand hazardous waste exposure risks. D e St In responding to its statement of task, the committee attempted to survey research completed or underway in other federal or state agen- cies that it could use in formulating a long-term research agenda for the EM Science Program. The committee attempted to identify those research programs that seemed to be most closely related to the EM Science Program and to gain a general understanding of research objec- tives. The committee believes that this review has provided enough information to make the following five observations that will be used to formulate recommendations for the long-term research agenda present- ed in Chapter 6. C h a p t e r 4 67

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1. The federal government is a major sponsor of basic research relat- ed either directly or indirectly to environmental problems. The committee identified almost 50 research programs in its survey (see Table 4.1~. If health-related research programs were included in the committee's survey, the number would be much higher. 2. There are a large number and variety of programs across the fed- eral government that support research of direct relevance to the EM Science Program and DOE's cleanup problems. The commit- tee identified 18 such research programs. 3. There appears to be significant overlap in scope among some of the programs identified in this analysis, judging from the pro- gram descriptions given in Table 4.1. Overlap is not necessarily undesirable, but it is not clear whether there is an effective mechanism to coordinate these programs. There are some notable exceptions to this generalization, especially for those programs listed in Table 4.1 that are jointly managed by several agencies (e.g., the Strategic Environmental Research and Development Program, which is managed by the DOD in coop- eration with DOE and the EPA.~. 4. Many of the 18 directly relevant programs identified in point 2 above focus on hazardous chemicals, and to a lesser extent on heavy metals. There appear to be few programs that address red ion ucl ide contam i nation outside DOE. 5. Many of the 18 directly relevant programs also focus on remedi- ation, and especially bioremediation. Other remediation approaches and other important research topics related to envi- ronmental cleanup (e.g., contaminant location and characteriza- tion in the subsurface) aooear to be receiving less attention. , , The committee believes there would be value added to the federal government's basic research on environmental problems if there was better coordination among its research programs, especially the mis- sion-directed programs. The committee sees an opportunity for EM Science Program managers to promote and foster such coordination. There are many good coordinating mechanisms that have been used elsewhere in the federal government that could be adapted to coordi- nate these m ission-d i rected envi ran mental research programs. These range from formal coordinating mechanisms like the Federal Remedi- ation Tech nologies Rou ndtable~ to more i nformal mechan isms I i ke Writhe Federal Remediation Technologies Roundiable is an interagency coordi- nating group comprising representatives of federal agencies with hazardous waste cleanup responsibilities. The roundtable provides a forum for information S U B S U R F A C E S C ~ E N C E 68

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period ic meeti ngs of i nterested program managers, or even joi nt spon- sorship of field research sites to address specific contamination prob- lems. Regardless of the mechanisms, however, the objective should be to improve communication among federal program managers, reduce unnecessary duplication and overlap among programs, and help pro- gram managers focus their resources on those problems that provide the greatest challenges to the nation's environmental cleanup efforts. exchange and joint action concerning the development and demonstration of innovative technologies for hazardous waste remediation. Additional information is available at http://www.frtr.gov. C h a p t e r 4 69

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1 4 A an - o ~ ~ o C~ v] ~ LO ~ - Lo - ~ 4~ at x LO 4J f ~ u v] ~ .m c an 4_ vie ~ o ~ ~ A m. cry ~ u ~ ~ ~ o c c ,~5 v] P u ~ o 0.) Q ~ 4 O Q Q . v] a ~ ~ ~0 Q _ . U .0 0 > .0 U U A ~ U o V] U O O ~ A ad 4_ ~ ~ 4 O ~ Q Lo U 4_ ~ O as . O Q Lit ~ ~ .c ~ O U at an c > ~ ~ U at (~5 ~ 4 ~ ~ > V) ~ U a~ O a~ ~ ~ V] . _ a~ a~ V] a.' ~ ~ a.' ~ ~ U ~ J ~ ~ ~ 2<~~ U Q ~ C (D .m ~ V] - o . _ 4 N o - 4 U V] 4 o . _ ~ O ~ . . L~ L~ > o 4 ~U a~ V] a~ V] 4 o Q Q V] - a~ o a~ 4_ ~ ~ a, C h a p t e r 4 1 ) ~ c ~ ~. .c .c .c .c L~ a~ x L~ _ 4J z~0 mE oo ~ ,~ ~ c~ ~ a.~ L0 c~ co 1~o .c > v~ oo ~ ~ ~ a~ .o ~ >~ .4 .4 4 a~ ~ ' a~ ~ ._ - ~ .~ . v~ >~ ~ - .c . - ~ ~ o a, > o . L~ a~ a~ L~ ~ ~u a~ - [^ .o - ~ - a.' ~ 0 0 o v] ~ u ~ v] 4J ~ ~ o o o c ~ f ~ ~ ~ ~u ~ ~ ~ co ~ ~ o 4J v] o U Q O 0d (,, O ~ C ~, u a~ > 0 Q O ~ Q ~ _ (~ C~ ~ ._ ._ ~ . ~ O ~ (,, O c C~ a~ (D O o Q (D L~ ~ g O a~ .c ~ ~ O (~5 ~ ~ Q U 0 ~ a~ a.' ~ .4~ - 4_ a~ .> ~ a~ ~ O ~ 0m . tr} a~ ~ U C o ,o C o L0 0 0 ~ ~ 4_ U Q (~5 U Q O 0~ U 0 ~ a.' ~ ~ ~ 9 C ~ ~ o O ] v~ a~ 4~ f ~ a.' ~ ~ Q O ~ _ o ~ f >~ ~ ~ U Q ~^ ~ Q ._ U ~ o > ) U ~ U C ~ O O O ~ ~ ~ ~ ~ .C O 0 =0 - V] 4 a~ ~ 4 .. Q 4 V] ~ U ~_ a~ U >~ ~ ~ E ~o ~ ~ ,~5 .. .. = ~ ',o U a) V] V] U ~ ~o L~ ~ ~_ u V] a~ V] >~ _ 4_ U o Q a~ ~ u ~ a~ a~ L~ v] ~ o o o) > ~ c o 4J u ~ .u 4J ~ Q ~ ~ a~ O O) Q . _ . _ ~ ~ > ~0 a~ ~ v~ U ._ 4~ . a~ ,~5 a, .c V] ~ ~ a~ ti U ~ a~ ~ u Q ~ 4X- 4 - ~ L~ o Q v ~ O .c 4 ~ V] ~ V] 4_ > 0 4 a~ u ~ O ~ O '_ a) ~ ~ > a~ E o ~ c V1- ~ ~ ,0 ~ 4- U V] U o o v~ oc 4_ Q ~ ~ . ~ ~ ~ 'C 0~ C O 0d a~ v~ u a=d O ~ ~ ~ ~ a~ ~ ,~5 U ~ U ~ :~. ~ Q .c a~ 4- ~ V] ~ ~ ~ ~ >~ 4- ~ ~ a~ u O 0d u ~ ~ - Q ~ ~ a.' ~ ~ ~ o U ~ = ~ ~ a~ 4- cD f C Q 0d U O O ~ Q ~ O ~ a~ ~ O om ~ U ~ Q Q ~ 0d . ~ ~ O ~ ~ U^-O ~ O ._ 4 Q U .V) Q ~ (~5 ~ Q O a~ ~ 4_ V] ~ V] ~ ,u ~ ~> ~ c ~- :^ c, E c,, O ~ ~ X .O ~ ~ ~ ~ Q ~ 4- ~ ~ ~ ~ Q Q ~ = V) 0~ o 0~ U o (~5 ~ 4 ~ =-0 ~ ~ a~ 0 > v~ ~5 a~ ~ ~ ~ ~ Q~ ~ <' Q V] ~ O 5 ~ a~ ' o ~ o E (~5 ~ o ~ U 0d 0~ ~ ,,, Q _ N 0d (~5 a~ ~ _ x 4 ~5 U ~ ~ O ,5 ~ ~ O a~ U a~ ~ ~ Q ~ O ~ ~O o U - ,~5 Q ~ >~ v) ~ o ~o (~5 ~ o E ~ <,, ~ ~ 0d ~ ~ Q a, a~ ~5 0 .m O O ~ ~ ~au c~ U E m _ O) ~ 4 Q 4_ L O a~ a~ v) a~ E E Q a~ O a~ a~ U . U ,~5 ~ ~ a ~ v~ a~ ~ >~ a~ ~ ~ 0 ~ 0d 4~ Q (~5 4 - > V] ~ 4 0 4_ Q O ~ (~5 0~ Q 4_ 0~ 0d ~ ~ U O Q 0.' m a, ,5 ~ a~ ~ ~ ~ ',o a~

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4J v] an as 4J o v] ~5 an . A l red 1 v] an an .E o Q Q an O V] an V] Q Q V] Q U ~0 '_ an an ,5 > > a~ a~ O) Q O U = 40- a~ ~ V] ._ o.m ~S O ~ a~ ~ L0 - 0d Q ~ ~ ' ._ Q ~0 ~ ~ v~ a~ a~ 4, ~ O U a~ ~ U V] .m ~,o a~ v] a~ ~ V] .-0 U ~ a~ C,0 V] .c ~ ~ ,5 ._ ~ ~ a~ 4. a~ ~0 - Z > O ~ ~ E Q U (U ~ O O - V] 4 j ~ U ~ U - Q v 4 4 ~ U O ~ ~x 1 ~ > .c L~ ~o ~ o - c . - o (Is > U Q C) C) O - U U a~ V] a, ._ 4 > U v] ~ a~ v] O ~ m ~ ~ 4^ ~ a.' L a ~ ~ u a~ o ~ ~ O U V-} ,~ > V) o U 0 4 ~ ~ ~ ~ O ~ o ~ ~ U U > 0 4 ~ (D ~ U al 'u f ~ ~ ~ a~ ~ >~ 0 ~ ~ ~ ~ ~ ~ ~5 ~ ~ ~ ~ U 0 C ~ ~ ~ ~ ~ [ co O~ , 0 au ,U r~ L ~, ~ ~ ,~ cD o ~ O ~ ~ o ~ ~ Q ~_ v) ~ a~ ~ > ~ O 9 ~ E U ~ > ~ ~E ~ ~ ~ '~ c,, E ,`, ~J (D Q u 0 au a~ ~ 4_ O _ t,) O ~ ~ a.' ~ a.' Q E ~ .,, u ~ o ~ ~,o >~ ~ ~ a~ u .c,, E +, .= o a~ ~ ~5 a~ 0 0 ~ 4_ ~o - ~o V] ~ Q U 4Q Q X L~ CM >~ 4_ ~ a.' ~ a~ U .. ~ = O L~ L~ ~ .u >~ ~ a~ a~ 0 a~ a.' 4~ Q ~ 0d ~ a~ ~ ~ 0 O o ~ (, U O .c ~ ~ V] a~ V] E <, c~ u ~ a.' ,~ V] U o ~o ~,o .m ~ ] U ~ o ~ 4_ 0 ~ 4 a~ = U V] ~ a~ >~ 4_ ~ ~ V] a~ ~ ~ ~ ~ o v~ ~ Q ._ O U 0 ~5 ~ L U U a~ U ~' Q =- o U ~ ~ o 4_ .U U ~ ~ o .m ' .u a, <~, ' E .U c, E . ,` o C~ O a~ a~ o U ~ ~ a.' v~ U U 4 V] U ~ V] ~ ~ V] .t,, 0 a.' a~ 0d a~ Q >~ ~ ~ 4 ~ ._ V] V] a.' u ~ ~ a~ a~ ~ ~ ~ 4_ ~ el C 0 4 O wo O O 'f .c ~ U U .o 4 U a~ u . - ~ ~ ~o Lu ~ o v] 4J Q 0d v~ )m 'E E o ] ~ ~ ~ Q ~5 U U 4 Q .m a~ o 4 L0 ~ .U ~ _ ~ 4 - 0 ~ L~ >~ ~ U .U O O ~ .m ~U > .c _ ~ 4 V] ._ a~ a~ a~ O ~ ~ ~ ~ @ ~ U o o ~ U ~ U ~ o U a~ ~ u ~ ~ ~ o >. ' ~ a.' a~ ~ ~ U ~ o .U ~ . o o ~U o U :- V] (~5 o O a~ Q ~0 ~ V] ~5 . a~ v~ .v] ~ .c ~ u u .o 4J u a~ u . - S U B S U R F A C E S C I E N C E

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4J v] ad ad 4J o v] ~5 Ad . of l red 1 v] ad A .E o Q Q ad O V] ad V] Q Q V] Q U it_ a~ a~ ,5 > > a~ a~ O) Q O U = 40- a~ ~ V] ._ o.m ~S O ~ a~ ~ L0 - 0d Q ~ ~ ' ._ Q ~0 ~ ~ v~ a~ a~ 4, ~ O U a~ ~ U V] .m ~,o a~ v] a~ ~ V] .-0 U ~ a~ C,0 V] .c ~ ~ ,5 ._ ~ ~ a~ 4. a~ ~0 - Z > O ~ ~ E Q U (U ~ O O O ~ L~ > - .c L~ ~0 O _ C _ -O `~S > U Q C) C) o - o o U o C~ CC U z .c ~ o ~ ~ .m 4u .o L Q ._ L U U~ a~ a~ a~ ~ c O) o Q Q a~ O ~ u a~ ;~ ~0 U ~ a~ _ O ~ ~ a, .0 ~ ~ L0 ._ ._ > L~ . _ U o ? V] a~ 4 V] o o :~ V] Q V] . _ 4 a~ o . _ V] U a~ o V] U a~ a~ a~ ,~5 ~ u O ~ ~ O 77 j2=O V] V] o o > ~0 Q o . _ 4 . _ 4 a~ ~ .m a~ V] ._ ~U 4 ~ 5 U `,, ._ ,~5 ~ . ~ ~ .c ~U a~ U~ Z ~ 00 O O ~ 4 ad - u O ~ ~ Q 4 ~, O V] V] O ~r, O O a~ x a~ ~ ~ .m O a~ a~ 4~ 0d 0 Q Q ~ U >~ >~ U 0d ~Q U ~ U V, a.' ~ V] u ~ a~ ~ ~ O 4 a.' > a~ O > ~ f .U ~ 4. v] a.~ v] ~5 V] V] ~0 .ad O Q Q U 0.) r~ ~ ~ ~ U .> ~ a~ U V] ~ > Q ~ r<5 a~ Q a~ ~ ~ a~ U ~ ~ ~ O ~ ~ O U (~ c >~.m ~U ~ ~ ~ O f O a.' L > U ~ a~ U O ~ U .m a~ ~ ~ O ._ g a~ ~ ~ .m .m a~ a~ a~ ~ O > a~ O c, ~ ~ v~ a~ ~ a~ 4 E a~ ~ a ~ co U C, u co ~ ~5 ~ 0 ~ '~ ~ ~ ~ a~ - = ~ (~5 a~ ~ ,~ a~ ~U > 0 4_ ~5 ~ >~ ~ ~ a~ ~ ~ ~ Z ~ ~ ~ O 0o -~0 4 o o o . _ 4 .N a~ u ~U ~ ~ U 0 ~ a~ ._ .V] U a~ _ o b o5=u > . u ~ a~ a~ U Z o o 4J a~ U C~ o ~ o X .o U ~ L0 a~ C,0 o ,, ~ ~ o V] =.U v~ 0 a~ ~ V] U ~ ,5 a~ ~ >~ a~ Q O a.' v~ ~ u ~ O . Q V] ~5 .m ~ ~ a~ . ~ - ~ a ~ v] .0 ,~ O ~ O ~ (,, ._ a~ ~ ~ ~ C,0 ~x V] 4 ~ ~5 a~ a.' ~ O 4_ ~_ .4 o ~ > ._ ~ ._ V] o ~ IO o a~ CM a~ ~ a~ Q ~ ~U .c .V) a~ Q 0d = = ~ _ ~ a~ U O U ~ ~ C U ~ n' .c ~ :m ~ a~ ~ w) Q v~ V] a~ ~ O ~ ~ 4_ O ~0 ~ ~ V] ~ ~ 4 ~ ~ .c ~ S U B S U R F A C E S C I E N C E

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