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Assessment of the EM Science Program Portfolio The Environmental Management (EM) Science Programs has been in existence for about four years and has completed four proposal com- petitions.2 The program has supported research projects relevant to many aspects of DOE's cleanup program, for example, research on subsurface contamination, high-level waste, and deactivation and decommissioning. In its 1998 report to Congress (DOE, 1 998g), DOE identified 82 EM Science Program projects with a total investment of approximately $70 millions that address the remedial action problem area, which focuses on the cleanup of soil, surface water, and ground- water at sites where contaminants or contaminated materials have been spilled, dumped, disposed, or abandoned (DOE, 1 998a, p. 2-9~. The first two proposal calls did not provide detailed descriptions of DOE's cleanup problems, and the proposal review process (see Appendix A) focused first and foremost on identifying scientifically mer- itorious projects for funding. Relevance to DOE's problems was consid- ered only for those projects that were deemed to be of high scientific quality. Thus, as this committee began to address its task statement to provide advice on a subsurface research agenda (see Chapter 1), it asked itself the following two questions, which provide a focus for the current chapter of this report: Was discussed in Chapter 1, the current program was established by Congress in fiscal year 1996. Previously, the Office of Science and the Office of Environmental Management (EM) jointly managed a one-year pilot project that awarded about $5 million in 3-year grants for research on EM-related projects. 2The four completed competitions were held in fiscal years 1996, 1997, 1998, and 1 999. The 1 999 competition was completed wh i le th is report was i n review. 3Many of the awards are being funded over multiple years and are therefore subject to future congressional appropriations. C h a p t e r 3 47

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Category Projects Research Focus Fundeda vet Al . _ u 0 ~ Al ~ .4J 1. To what extent does the EM Science Program research portfolio for fiscal years 1996 and 1997 address DOE's significant subsur- face contamination problems? 2. In light of these current investments, are there any particular sub- surface problems that should be emphasized in future proposal Cal Is? The committee reviewed all projects awarded funding during the first two proposal competitions (in fiscal years 1996 and 1997) and attempted to assess the extent to which these projects addressed the cleanup problems identified in Chapter 2. The word "attempted" is used advised Iy, because these projects were sti 11 i n progress at the ti me of the committee's review and therefore the research results were incomplete. Moreover, the committee did not review research results for scientific merit in the way that one would review papers submitted to refereed journals, so it cannot comment on the quality of the work resulting from these projects. The committee's assessment is based on a review of project titles, principal investigator experience and affiliations, project abstracts as provided in DOE's 1998 report to Congress (DOE, 1 998g), and on a review of progress reports provided by the principal investiga- tors, which were published in the proceedings volume of the Environ- mental Management Science Program Workshop (DOE, 1 998c). This TABLE 3.1 Summary ofthe EM Science Program Portfolio for Fiscal Years 1996 anc 1997 anc Pilot Projects Funcec in Fiscal Year ~ 995 Methodology >I o >I ~ 0 ~ 4J ,0 a .o ~ 0 .4 ~ Number of Multiple Investigator Projects Identify 30 Contain 6 Remediate 37 Remove 7 Validate 9 Other 16 3 1 14 24 6 1 6 8 3 16 4 NA 10 NA 0 NA 2 3 7 NA 23 12 4 5 35 7 6 o 17 1 5 3 5 13 2 6 aThis column sums to 105 projects, because some projects were included in more than one category.There are 91 separate projects represented by the data in this table. bProjects that focused on characterization of the site rather than on specific contaminants. SOURCE: DOE (1998c,g). S U B S U R F A C E S C I E N C E

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40 35 30 IL a, 25 o o 5: at 20 15 9 7 16 Contain Remove Validate Other 37 30 Identify Remediate workshop was held in Chicago, Illinois on July 27-30, 1998. These analyses are summarized in Table 3.1 and Figure 3.1. The committee spent a considerable amount of time during its first two meetings discussing the merits of various organizing schemes for this assessment and eventually adopted a slightly modified form of an approach that is used by DOE's Subsurface Contaminants Focus Area4 to organize its technology development programs (see Figure 3.2~. This organizational scheme comprises a five-point technical strategy that is based on what the focus area refers to as "the accepted process for the remediation of contaminated sites" (DOE, 1 997b). This scheme consid- ers the generic processes that must be employed to remediate a site (e.g., locate the waste, treat the waste, validate the treatment process) without reference to the specific technologies that will be employed to accomplish these processes. The committee adopted the focus area's Identify Contain ~ | Remediate > ~ Remove Validate 4The Subsurface Contaminants Focus Area is part of the Office of Science and Technology, which is responsible for developing technologies for cleanup of the DOE complex. The EM Science Program is also part of this office. C h a p t e r 3 FIGURE3.1 Distribution of subsurface research projects in the EM Science Program portfolio for fiscalyears 1996 and 1997. The num- bers in the graph are the number of projects funded in each topical area. FIGURE 3.2. Flow chart for remediation of subsur- face contamination (DOE, 1 998d, p. 4). 49

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tunct~on names, slightly modified some of the function descriptions, and added an additional category ("Other") to its analysis to contain those projects that do not fit readily into one of the focus area's categories. The resulting organizing scheme used for the committee's assess- ment is shown below: Identify Locate and quantify suburface contamination. Contain Contai n or stabi I ize mobi le contam i nants and local Iy elevated contaminant concentrations (i.e., contaminant hot spots) in situ. Remediate Treat to reduce mobility or destroy mobile contami- nants in situ. Remove Extract contaminant hot spots that are not amenable to in situ treatment. Validate Verify conceptual models and the performance of remediation processes or strategies. Other Projects that address subsurface contamination prob- lems, but do not fit into one of the preceding categories. The committee adopted this scheme for organizing its assessment mainly for convenience, but also because this scheme could provide a direct linkage between basic research in the EM Science Program and applied technology development in the Subsurface Contaminants Focus Area. As will be discussed in Chapter 6, moving the results of basic research from the EM Science Program into application at the sites is a major challenge confronting DOE. The committee hopes this organizing scheme will provide a useful mechanism for identifying potentially fruitful application paths for EM Science Program-sponsored research. A summary of the committee's assessment of the current program portfolio is provided in the following sections. A concluding section provides a brief discussion of the two questions posed at the beginning of this chapter. Identify The radioactive and hazardous subsurface contaminants of concern at DOE sites (see Chapter 2) have entered the soil and groundwater through accidental spills, poor waste management practices, and failure of storage and containment systems. Even in cases where the points of contaminant entry into the subsurface are known, information on tim- ing of entry and contaminant quantities may be lacking. Once intro- S U B S U R F A C E S C ~ E N C E

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duced into the subsurface, the contaminants are subject to a number of physical and chemical processes or biological degradation. Sub- surface heterogeneities may make it difficult to predict contaminant movement away from release sites. Successful remediation of contam nated su bsu rface sites depends fi rst and foremost on the abi I ity to locate and quantify the nature and extent of contamination, the focus of this category. The committee found 30 projects relevant to the "Identify" category in the portfolio (see Table 3.1~. These projects encompass a wide range of topics and approaches, but in general focus on the following: (1 ) location and spatial distribution of contaminants in saturated and unsat- urated environments; (2) methods to estimate quantitatively the extent of such contamination; and (3) methods to monitor the movement of subsurface contaminants. The projects in this portfolio address a wide range of contaminant types and site characterization problems. Organic contaminants (espe- cially non-aqueous phase liquids) are the subject of 12 projects, com- pared to three for radionuclides and one for metals; 16 projects focus on site characterization without regard to contaminant type. A majority (23 projects) involve field investigations at contaminated sites. In terms of project objectives, three focus on elucidating contaminant properties, four on elucidating subsurface properties, 13 on the development of invasive characterization techniques, and 12 on the development of noninvasive techniques. The projects in this portfolio address many of the subsurface prob- lems described in Chapter 2, including aspects of the following topical areas: development and testing of noninvasive techniques to identify the distribution of non-aqueous phase liquids in the subsurface; development and validation of analytical and modeling tools to be used in subsurface process representation and characteri- zation; development of techniques and instruments to determine subsur- tace parameters that describe flow of water and contaminant transport in the subsurface; and noninvasive geophysical techniques and associated analytical , . .. . . .. .. . . techniques to determine subsurface physical parameters. The portfolio is heavily weighted toward organic contaminants, and there are relatively few projects on metals and radionuclides, which are significant problems at most of the large DOE sites. There are also very few projects that deal with the behavior and transport of contaminants C h a p t e r 3 51

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in fractured systems, primarily under unsaturated conditions, or the behavior and transport of contaminants under near-surface conditions (e.g., in near-surface release sites). Contain The removal and treatment of contaminants from waste burial grounds is technically difficult, expensive, and could expose workers to radiation and hazardous chemicals. For these reasons, DOE does not plan to fully remediate subsurface contamination at some of its sites. Instead, DOE plans to contain the waste at such sites with surface caps and subsurface barriers to minimize water infiltration and contaminant movement. Remediation of contaminated soil and groundwater at many DOE sites is technically impracticable with current technologies, so DOE plans to monitor this contamination and treat it where necessary, using technologies such as pump-and-treat systems to prevent its further spread.5 Thus, the availability of robust containment and stabilization technologies will be a key factor in the success of DOE's strategy to manage subsurface contamination. Given the importance of containment and stabilization technologies to contamination management strategy, the committee would have expected to see a large number of projects on this topic; however, the committee was able to identify only six relevant projects in the portfolio (see Table 3.1 ). In general, these projects are concerned largely with metals and radionuclides and the kinetics and mechanisms of contami- nant retention and release through various processes. Five of the six projects focus on chemical stabilization, one on biological stabilization, and one on physical stabilization.6 Only one of the six projects has a significant field component. The committee concluded that there are significant research gaps in the portfolio in this category. These gaps7 include basic research on the 5Pump-and-treat systems are used frequently to remediate contaminated groundwater. It involves pumping the contaminated water to the surface for treat- ment and then reinfecting it. See NRC (1994) for a discussion of this technology. 6The current portfolio supports several projects on phytoremediation. These are discussed under the "Remove" category elsewhere in this chapter. 71n the context of this analysis, the committee defines a research gap as a defi- ciency in the number or scope of research projects that address the difficult DOE cleanup problems identified in Chapter 2. The identification of gaps involves a significant element of judgment, especially in interpreting the significance of the subsurface contamination problems now at DOE sites. These cleanup problems and associated knowledge gaps are discussed more fully in Chapter 5. S U B S U R F A C E S C ~ E N C E 52

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design, performance, or effectiveness of engineered surface or subsur- face barriers, including capillary or resistive barriers, reactive barriers, or hybrid barriers that incorporate biological materials; and research on subsurface processes that address the potential effectiveness of natural barriers in contaminated areas, particularly in the vadose zone. Remediate Technologies for in situ treatment and destruction involve the use of engineered or artificially manipulated natural processes to promote the conversion of subsurface contaminants to nonhazardous or less haz- ardous forms. The committee identified 37 projects in the portfolio (see Table 3.1 ) that address a wide range of chemical, physical, and biologi- c~al treatment and destruction Processes. including the following: bioremediation,8 including biological interactions, genetic eng neeri ng stud ies, and toxicity stud ies; in situ physical and chemical treatment, including electrochemi- cal processes; filtration; sorption; and reactive subsurface barriers such as metal (Fe, Mn) oxide barriers, including passive or low- maintenance barriers; . . coupled chemical, physical, and biological treatment processes used i n paral lel or series; and elucidation of fundamental subsurface processes that govern the effectiveness of in situ treatment or destruction (e.g., evaluation of the effect of soil heterogeneities on treatment processes). Projects on organic contaminants comprise the majority of the port- folio (24 of 37 projects), whereas only 10 projects address treatment of radionucl ides and 1 4 address treatment of metals.9 The committee was able to group the projects into one or more of the following five the- matic areas: (1 ) development of new genetic materials to degrade or alter the chemical composition of DOE's most problematic wastes, including mixed wastes containing radionuclides, heavy metals, and 8Bioremediation generally refers to the removal of contaminants from soil or water through the metabolic action of living organisms, and the term is commonly used to indicate situations in which humans have interceded to bring about or hasten the biodegradation of contaminant compounds. Although bioremediation can be carried out by any living organisms (e.g., as in phytoremediation), it is usu- ally considered to be a product of the metabolism of microorganisms such as bac- teria or fungi. 9Some projects address more than one contaminant type. C h a p t e r 3

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solvents; (2) elucidation of molecular-level biochemical, geochemical, and biogeochemical processes to degrade or transform selected waste components; (3) taking basic science results to the technology imule- . . . . O. , mentat~on level to develop In sits engineered systems; (4) development of improved analytical methods to allow evaluation of the effectiveness of in situ treatment or destruction; and (5) development of improved understanding of transport processes at all scales in heterogeneous sys- tems that affect the movement of contaminants in the subsurface. The portfolio defines a fairly coherent research program on in situ treatment and destruction, but there are a number of significant gaps as outlined below, and for some research topics there appears to be dupli- cation of effort. The following observations are, in the committee's view, most significant: There is a predominance of projects that address bioremediation relative to projects that address chemical and physical processes. Research on treatment and destruction in the vadose zone is underrepresented. Research on sensors is big-oriented and much of it is aimed at tracking the biological "health" of subsurface systems. In the bioremediation area, there is an absence of projects cover- ing (1 ) alternate electron acceptors, including iron and nitrate, and aerobes (the issue of aerobic degradation is important for vadose zone applications); (2) toxicity of some chemical contam- inants found at DOE sites to bacteria that could potentially degrade other contaminants; and (3) cellular mechanisms and processes important to the bioremediation of radionuclide and organic contaminants, including the byproducts of microbial degradation activity. Understanding what controls the availability of many contami- nants to degrading organisms or to reacting chemicals is needed. Remove DOE uses the term "hot spot" to refer to significant contaminant source terms in the subsurface that cannot be treated by in situ methods (DOE, 1 998d). In lay terms, a hot spot is a distinct high-concentration contaminant anomaly in the subsurface (e.g., a pool of non-aqueous phase liquids trapped in a waste burial ground or a buried 55-gallon drum filled with plutonium-bearing scrap metal). Removal of hot spots involves the physical extraction of the contaminant from the subsurface for ex situ treatment or disposal. S U B S U R F A C E S C ~ E N C E

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None of the projects in the EM Science Program portfolio have a specific focus on hot spots, however there are seven projects (see Table 3.1 ) on phytoremediation, an intensely pursued approach to soil cleanup and extractive technology for treatment of hot spots. Research projects include the study of genetic factors controlling the uptake of heavy metals by plants, transport of heavy metals across plant cells, and the ability of plants (poplar trees) to take up and degrade chlorinated hydrocarbons. Moreover, many of the projects are relevant to improved decision making about whether to contain, stabilize in situ, or extract hot spots for above-ground treatment. For example, some of the projects in the "Other" category discussed later in this chapter are relevant in this regard. Some of the stud ies i n the portfol io on removal and neutral iza- tion of contaminants in tank wastes may lead to results useful for treat- ment of extracted hot spot materials. Similarly, research projects on locating and quantifying contamina- tion, which were discussed earlier, could make the location and defini- tion of hot spots easier, faster, more accurate, and more economical. Moreover, there are projects in the portfolio that address reactive barri- ers, bioremediation, in situ vitrification, waste treatment and extraction using electrokinetics, non-aqueous phase liquid migration and pooling, surfactants, adsorption-desorption reactions, and contaminant transport. Many of these projects fall into the "Other" category discussed later in this chapter. The challenge to DOE is to understand and apply the results of this research in dealing with hot spots in reliable and cost- effective ways. Validate The Subsurface Contaminants Focus Area defines "Validate" as "vali- date and verify system performance for regulators and stakeholders" (DOE, 1 998d, p. 4~. The committee has adopted a somewhat more expansive description that includes confirmation of the effectiveness of remediation processes or strategies. The committee also includes in its definition the validation of conceptual models and the performance of quantitative models of contaminant fate and transport. Under the com- m ittee's expanded defi n ition, performance val idation is a major factor in regulatory acceptance. It underpins all of DOE's site remediation activities and provides tools and methods to assess the effectiveness of cleanup efforts. The committee identified nine projects that address the problems in this category (see Table 3.1~. Two of these projects address validation of C h a p t e r 3

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contaminant detection and characterization, three address the valida- tion of fate and transport (i.e., performance of models for fluid flow), and four address remediation effectiveness (i.e., validation of in situ biodegradation or immobilization efforts). The portfolio does not, how- ever represent a coherent research orouram in the validate performance _ , _ ~ _ _ ~ O area. Notably absent are projects to validate long-term performance of containment systems, including containment barriers. Also missing from the portfolio are projects to develop protocols for validation of concep- tual and numerical models of contaminants in the subsurface. The com- mittee believes that validation is a key area for future work by the EM Science Program, as explained in Chapter 5. Other The portfolio includes several projects that have indirect but poten- tially very significant applications to DOE's subsurface contamination problems. In particular, the program is supporting several projects on the biological effects of radiation and hazardous chemicals, including impacts on health and risk (see Table 3.1~.~ Relevant projects fall into the following four thematic areas: 1. effects of radiation and hazardous chemicals on human health and risk (seven projects); 2. effects of contaminants on ecology and ecological risk (three projects); 3. genetic or molecular basis for contaminant effects (four projects); and 4. assessment of monitoring techniques for environmental contami nants (two projects). None of these projects addresses explicitly the remediation of sub- surface contamination, but they are nevertheless relevant to subsurface cleanup efforts because they contribute to the body of science that reg- ulatory agencies use to set cleanup standards and levels. These projects do not define a coherent research program on biolog- ical effects and, in fact, the portfolio of projects could be characterized as meager, given the potential significance of this area on DOE's cleanup efforts. 10As noted in Chapter 1, the EM Science Program awarded funds for research on low dose radiation in fiscal year 1999. S U B S U R F A C E S C ~ E N C E

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Discussion And Conclusions . The EM Science Program is by design a "bottoms-up" program in which investigators are encouraged to submit their research ideas to address cleanup problems. In this respect, the program is not unlike , . . . . . . . , , , ~ other basic research programs operated in DOE's Office of Science and other federal agencies, like the National Science Foundation. Funding decisions are based on the scientific merit of the research proposal and its relevance to DOE problems (see Appendix A). The selection process has resulted in many scientifically meritorious and relevant projects, but there has been a limited opportunity to build coherence. The committee discusses ways to increase coherence in Chapter 5. The EM Science Program is nevertheless supporting 91 projects focused on subsurface contamination problems and on health and risk effects that are potentially relevant to these problems. It is not unreasonable to expect that the program will attain a critical mass of projects in some problem areas. The purpose of the assessment in this chapter is to determine where these critical masses are present and to identify important gaps in the portfolio that DOE should fill in future competitions. Of course, the committee recognizes that some of the gaps identified may in fact be addressed in other federal research pro- grams and in more recent EM Science Program proposal awards. A dis- cussion of other federal programs is provided in Chapter 4. The program portfolio in subsurface research has some significant areas of strength. For example, the portfolio has a good selection of projects that address organic contamination problems (50 projects) and that use field-based approaches or a combination, of field-, laboratory-, and modeling-based approaches (38 projects). There appears to be a critical mass of projects in the "Remediation" category, especially for treatment and destruction of organic contaminants through physical chemical, and biological processes. The committee did observe gaps in the portfolio in this problem area, as noted previously, but these are minor in comparison to gaps in other categories. The most notable gaps in the portfolio are in the "Contain" and "Validate" categories, two of the most significant problem areas for DOE given its plans to manage much of its subsurface contamination in place. In the "Contain" category the gaps include research on the design, performance, or effectiveness of engineered surface or subsur- face barriers. The portfolio in the "Validate" category (9 projects) is lim- 44There are 105 projects listed as funded in Table 3.1, but some projects were counted in more than one category. There are 91 separate projects represented by the data i n that table. C h a p t e r 3

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ited both in terms of depth and breadth of topical coverage. The most notable gaps include research to validate long-term performance of containment systems, including reactive barriers and cover perfor- mance, and research to address the validation of conceptual and numerical models of the subsurface and contaminant fate and transport. As noted elsewhere in this report, these are key problems for DOE because they underpin efforts to confirm the effectiveness of and obtain regu I atory acceptance for its remed i ation actions. There also appears to be a gap in the number of research projects covering radionuclide and metal contamination problems (26 and 31 projects, respectively). As noted in Chapter 2, radionuclide, especially transuranic, contamination is a significant problem, and transuranic contamination is almost exclusively a DOE-owned problem. As will become apparent in the following chapter, these contaminants are receiving relatively little attention in other federal research programs and therefore deserve to be emphasized in future EM Science Program competitions. S U B S U R F A C E S C ~ E N C E 58