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6 Nontechnical Issues Subsurface characterization is an essential component of many environmen- tal and engineering applications. If noninvasive methods are to become an impor- tant component of subsurface characterization, a number of issues, which have little to do with the state of technology or the availability of competent geoscien- tists and engineers, have to be addressed. Similar nontechnical issues are dis- cussed in two recent reports (Federal Facilities Policy Group, 1995; National Research Council, 1997~. This chapter explores a variety of nontechnical barriers to the application of noninvasive technologies to characterize the subsurface environment. Insuffi- cient economic incentives are a major impediment to the effective use of modern noninvasive technology. Legal and institutional constraints also can be impedi- ments to the effective use of noninvasive methods. These constraints include statutory and regulatory requirements, health and safety concerns, and the nature of standards and certification procedures. These impediments have the potential to inhibit creativity and discourage the development of effective solutions to site- specific problems. In some cases, institutional pressures and other demands can take precedence over scientific and technical judgments concerning a site, and this can be compounded by lack of information, misunderstandings, or miscon- ceptions on the part of one or more of the stakeholders involved (contractors, clients, regulators, and the public). INCENTIVES Researchers in the resource industries, federal laboratories, and universities have made significant advances in both instrumentation and methodologies. How 107
108 SEEING INTO THE EARTH ever, few of these innovations have found their way into routine practice in near- surface characterization. In a related area, a 1997 NRC report (Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization) assessed various reasons for the difficulty in applying innovations to environmental cleanup. These reasons include lack of market stimulation, information, technol- ogy testing, and cost comparisons. Similar nontechnical impediments appear to apply in the area of noninvasive technologies. According to the 1997 NRC report (pp. 7-8), "Lack of information has contributed to the slow transfer of new ideas for remediation technologies from the laboratory to the field and from one site to another. Technology reports are often incomplete and lacking in critical scientific evaluation and peer review. Reliable cost data are also lacking, Moreover, much information on prior experiences with remediation technologies is proprietary." A company faced with the responsibility of a hazardous waste cleanup might choose the needed site characterization and remediation methods on the basis of what will satisfy regulatory and legal requirements at minimum cost (NRC, 1997~. When dealing with a problem such as hazardous waste, in situ sampling is often required in designing cleanup methods. In such a case, many involved with a project may have the perception that noninvasive site characterization adds cost without commensurate benefit and that the added cost will not be recovered during the life of the project. Alternatively, some contractors have invested in a particular characterization method and often rely almost exclusively on this capa- bility. They may be reluctant to consider other characterization methods because of possible additional capital investment and/or the need to subcontract these methods. As such, the clients' perception of added costs of noninvasive charac- terization can be reinforced by many contractors' reliance on a specific, often invasive, technique. A key to greater use of noninvasive characterization is to demonstrate net economic benefits. The oil industry, for example, is quick to make large invest- ments in new technologies because even small improvements in exploration and production can significantly improve revenue and profit. Although the oil industry developed three-dimensional seismic methods over twenty years ago, these meth- ods remained little more than a research curiosity for at least a decade. During that time three-dimensional seismic images became widely used to guide drilling, and three-dimensional seismic reflection surveys are now the standard procedure for major oil companies and many independent oil companies. For example, ARCO averaged fewer than three three-dimensional seismic surveys per year during 1980 to 1982, but it averaged nearly 40 such surveys per year in 1993 to 1995 (Dorn, 1998~. The costs of research and development for the three-dimensional seismic methods and the costs of more extensive data collection efforts in the field were more than offset by the savings associated with fewer dry holes; there have been unsubstantiated claims of success ratios of over 80 percent. The economic benefits of noninvasive methods in resource exploration and recovery are apparent. For an engineering or environmental application, the use
NONTECHNICAL ISSUES 109 of properly evaluated and designed noninvasive characterization can have two benefits: the overall cost of the program can be reduced (due to the difference in cost between noninvasive characterization and drilling), and the invasive sam- pling points can be chosen to give maximum information (see Figure 4.9~. Noninvasive methods have the potential to reduce characterization costs. In many cases, noninvasive characterization provides comparable information at a cost that may be less than that of intrusive techniques such as drilling. In some cases, intrusive methods (e.g., drilling or digging) can engender major financial and environmental risks that can be avoided with noninvasive technologies. For ex- ample, a major oil company in Texas was faced with financial penalties relating to a refinery unless a leakage mitigation plan was developed quickly for a chemical storage pond. Drilling on approximately 50-m centers revealed the presence of, but did not delineate, a buried bedrock valley. A seismic reflection survey at the site sampled the subsurface at 0.7-m intervals, delineating two buried valleys, which enabled the refinery operator to develop a contingency plan that satisfied the state regulatory agency (Miller et al., 1989~. As another example, inadvertent disruption during construction of buried utility cables and gas pipelines is frequently in the news; noninvasive characterization might help avert such disruptions and their associated costs (National Transportation Safety Board, 1997~. Documentation of these benefits in the public domain is rare, and therefore, the cost-effectiveness of noninvasive characterization is difficult to establish. Most of the literature concerning noninvasive characterization emphasizes tech- nical developments. However, useful information about such economic benefits exists in related areas and could be made available. Government agencies, environmental and engineering contractors, and university researchers should work to analyze and document the potential costs and benefits of the use of noninvasive characterization methods in a wide variety of applications. There is a large amount of data (in the form of govern- ment-funded projects) that could be subjected to analyses, and an evaluation of alternative scenarios could demonstrate the potential benefits of noninvasive char- acterization. Documenting these benefits can demonstrate possible economic in- centives for the use of noninvasive technologies in site characterization efforts. OPERATIONAL CONCERNS To be effective, subsurface characterization efforts should have the flexibil- ity to design for site-specific conditions and to change or modify the characteriza- tion program as results become available. However, certain laws such as Superfund and the Resource Conservation and Recovery Act (RCRA) "provide a disincentive to change the selected remedy even if a much better solution evolves" (NRC, 1997; see Box 6.1~. Other nontechnical impediments to the application of noninvasive characterization arise from concerns related to (1) regulations, (2) standards of performance, (3) health and safety, and (4) institutional barriers.
0 SEEING INTO THE EARTH One or more of these impediments have been experienced by committee mem- bers while conducting or examining site characterization programs; others in the characterization community have expressed related experiences (e.g., Freeze and Cherry, 1989~. Similar concerns are discussed in reports of the Federal Facilities Policy Group (1995) and the NRC (1997~. Regulations Regulatory requirements may inhibit flexibility (NRC, 1997~. Both contrac- tors and regulators have a vested interest in adopting and following detailed, rigid, generic regulatory requirements regardless of site-specific conditions. If they can show that they followed every regulation to the letter, contractors have some protection from lawsuits regardless of the quality of their results. Regula
NONTECHNICAL ISSUES 111 tors can similarly protect themselves by trying to cover every possible eventuality with a regulation. These approaches can lead regulators to require and contrac- tors to provide subsurface characterization programs that are regulation driven rather than solution driven. Practitioners may satisfy regulatory criteria at the expense of sound profes- sional practice. Decisions are legally correct if the regulations are followed, and practitioners cannot afford the risk of deviating from the regulations. At present, requests for proposals and contracts for shallow subsurface char- acterization often prescribe methods and survey designs without consideration of site-specific conditions. Contractors or consultants with vested interests in cer- tain technologies or geographic regions may be tempted to encourage regulators and clients to continue this practice to avoid competition. To maximize the net benefits achieved from investments in federal facilities cleanup, the Federal Facilities Policy Group (1995) recommended (1) more rigor- ous risk-based priority setting and management oversight, both within and across sites; and (2) statutory and regulatory reforms to remove impediments to success. The report argues that regulators often specify how a site is to be characterized (i.e., what data should be collected by the specified technique) rather than speci- fying the overall objectives of the characterization effort. For example, if a regu- lator required that a ground penetrating radar (GPR) survey be done at a site, the presence of a subsurface clay layer could make GPR less useful than electrical methods at the same site (see Plate 6~. To provide the flexibility necessary to deal with such situations, regulations should specify how such decisions are to be made at each site rather than attempting to specify what the decisions should be. The Environmental Protection Agency' s (EPA) Office of Solid Waste and Emer- gency Response began in 1997 to implement a program called the Performance- Based Measurement System (PBMS) that aims to reduce the burden on the regu- lated community associated with the use of new site characterization and monitoring techniques. The objectives of PBMS are to improve data quality, reduce the cost of compliance by lowering regulatory barriers, and stimulate the development and use of innovative monitoring technologies (www.epa.gov/ ooaujeag/notebook/pbms.htm). Under PBMS, EPA would no longer prescribe the use of specific technologies but would specify an acceptable data quality level, which serves as a criterion for technology users to select the appropriate site characterization or monitoring techniques. Standardized Practices Laws and regulations may encourage or require the implementation of stan- dardized practices in site characterization, which offers some liability protection to practitioners. Standardized practices usually assume some consistency in problems and conditions. However, each site has unique conditions and problems that require site-specific considerations. The choice of characterization methods, design of the
2 SEEING INTO THE EARTH TABLE 6.1 Examples of Standard Approaches for Site Characterization Organization Effort American Society of Testing and Materials (ASTM, 1997) U.S. Environmental Protection Agency (EPA) EPA Office of Underground Storage Tanks (EPA, 1997) Department of Energy (DOE), Ames Laboratory DOE, Argonne National Laboratory California Environmental Protection Agency Accelerated Site Characterization Committee D-18 on Soils and Rocks Superfund Accelerated Cleanup Model Tools for Expedited Site Characterization Expedited Site Characterization Expedited Site Characterization (QuickSite) Environmental Technology Certification Program data acquisition program, and interpretation of results will be different for each site. This situation makes it difficult to develop generally accepted "best practices." Conflicts between scientific and technical issues and legal and regulatory concerns often beset site characterization projects. A high priority of the client (or owner of the site) is to ensure that all applicable laws and regulations are satisfied fully so that decisions and actions can be defended in court, if necessary. To achieve this objective, a "cookbook" approach is often followed, which may limit the flexibility needed to assess certain site-specific considerations. If clients can demonstrate that the prescribed procedures were implemented faithfully, they may be protected from legal action even if the results are less than optimal. The engineering community is generally comfortable working with a struc- ture of relevant certification and standardized approaches. Several groups (see, Table 6.1) have developed or are developing standard approaches or guidance to site characterization. These standard approaches are designed to promote proper techniques for site characterization and reduce the possibility of questionable site characterization practices. Incidences of questionable practices (Shuirman and Slosson, 1992), which could be called charlatanism, misuse, and fraud, led the Society of Exploration Geophysicists (SEG) to amend its charter to exclude corporate membership from companies whose practices were not based on accepted scientific principles. The SEG amended its constitution to say, "The services or products provided must be demonstrably based upon accepted principles of the physical sciences" (SEG Constitution, Article III, Section 9~. Upon adoption of this language, several
NONTECHNICAL ISSUES 113 companies were asked to disassociate themselves from the SEG. Such actions help raise the level of credibility of characterization efforts. Subsurface characterization programs should be customized for every site to achieve specific objectives within financial and time constraints. Some tools exist to assist nonexperts in the design and justification of such customized efforts. For example, the Geophysics Advisor Expert System (Olhoeft, 1992) can help select the appropriate geophysical tools to apply to EPA Superfund site problems. However, the details of such efforts should be planned and executed by multidisciplinary teams that may include geophysicists, geologists, chemists, geochemists, geotechnical engineers, biologists, and others as re- quired to achieve the site-specific objectives. Relevant disciplines should be represented from the outset of a major project, and members of the team should understand and adhere to a common set of decision-making processes and standards. Government agencies (federal, state, and local) need to develop approaches to site characterization that focus on flexible, program design procedures and decision-making processes that account for the unique character of each site. Design and decision-making processes and procedures should achieve a bal- ance between accountability and flexibility. Highly constrained procedures en- sure accountability, but they can inhibit the implementation of programs custom- ized to the unique characteristics of the site. Removing constraints ensures flexibility at the expense of accountability. Standardizing and documenting the structure and rationale behind the decision-making processes can provide legally defensible characterization programs that are well suited to the unique problems of a given site. Successful implementation will require that decision-making processes be peer-reviewed and certified and that universities offer academic programs that teach the processes as well as the technical foundation. Health and Safety Site characterization activities involve collection of data in the field and have some associated hazards related to worker safety and health; these can be quite varied. (Hazards related to the possible spread of contaminants from invasive sampling are addressed earlier in this report.) For noninvasive field methods, the hazards can be as simple as tripping and falling or as complex as those associated with using explosives. For explosive hazards the perceived risk can sometimes stop or alter the nature of seismic measurements. Seismic experimentation often uses explosive charges because of the wide bandwidth of the energy spectrum of vibrations these sources produce. In large- scale petroleum exploration, the explosives are extremely safe to handle but still
4 SEEING INTO THE EARTH produce large energy releases that can be dangerous. Near-surface seismics often use smaller explosive sources, similar to those contained in large-gauge shotgun shells that are detonated using a modified shotgun (Miller et al., 1986~. The shotgun-shell explosive source is relatively safe to handle, ship, and use. Yet many individual sites often limit the use of such relatively benign explosive . . seismic sources. Site-specific rules that may inhibit the use of such common explosive charges generally fall into two categories weapons or fire. For weapons, a site might have rules that prohibit firearms. Exception to this policy may be difficult to obtain even when the actual practice involves angering a hole and shooting a specialty rifle into the hole for the sole purpose of exciting elastic vibrations. With pressures on site managers to adhere to stringent safety rules, such permis- sion is often hard to get. Regarding the issue of fire, the concern of those in authority is more under- standable. Even though the shotgun-shell source is a contained explosion in an angered hole that is a few feet deep, there is a small possibility that the explosion could start a fire. Therefore, if flammable materials are present on-site, it is difficult to receive permission to use small explosive devices. As a result of such site-specific rules, seismic sources such as weight drops are often used instead of explosives. These alternative seismic sources are often adequate for the task, but in other cases, they are less than optimal and may not be able to produce the characterization objectives. Institutional Barriers A broad category of institutional barriers, discussed in a report by the Fed- eral Facilities Policy Group (1995), includes statutory decisions, competitiveness and infighting among agencies and contractors, the "not-invented-here" syn- drome, and "turf" protection. A relatively recent example of a congressionally mandated program involved buried UXO and mine detection advanced technology demonstration (ATD; U.S. Army Environmental Center, 1994~. The statutory provisions of the ATD pro- gram specified where the demonstration was to be conducted, which agency was to manage the demonstration, and technical details constraining the demonstra- tion. The ATD was funded at approximately $30 million over a three-year period (1994-1996~. Congress reacted to the complex technological requirements by attempting to specify the "solution," requiring off-the-shelf-technology demon- strations in the form of a contractor competition. The ATD program was prompted by the recognition of UXO and mine detection as an extremely high-priority issue and a desire to find the nonexistent "silver bullet" (see Box 6.2~. Several important elements were not included in the program. There was no comprehensive site characterization in advance of the ATD. No phenomenologi- cal predictions or assessments of results were conducted. Results reported by
NONTECHNICAL ISSUES 115 various contractors were not complete enough to allow a detailed phenomeno- logical assessment (Altshuler et al., 1995; Butler et al., 1998~. Details of the UXO and mine types and locations were not released to contractors or other govern- ment agencies, which would have allowed independent assessments and contrac- tor self-evaluations. Competition among agencies, turf protection, and the not-invented-here syn- drome can lead to major inefficiencies and barriers to effective subsurface char- acterization programs. A 1996 NRC report (Barriers to Science: Technical Man- agement of the Department of Energy Environmental Remediation Program) identified many of these barriers as factors that have hindered environmental restoration efforts of the Department of Energy' s Office of Environmental Man- agement. In addition, the Federal Facilities Policy Group (1995) reported similar barriers in an assessment of complex environmental restoration programs. This assessment found that not only is there competition among agencies, but there is also potential for overlapping regulatory authorities between state and federal governments that can lead to inefficient site characterization efforts (e.g., see Box 6.3~. Because of the pressures often involved in subsurface characterization and environmental remediation, agencies might attempt to redefine their mission ar- eas and develop programs to address these problems. INFORMATION AND COMMUNICATION As with most areas of emerging technologies, transfer of research advances into applications poses a challenge (i.e., closing the gap between the state of knowledge and the state of the practice). With noninvasive characterization meth- ods, such transfer presents a two-pronged challenge. One is to ensure that ad- vances in techniques and methods are communicated to the practitioners of char- acterization efforts; the other challenge involves the clients or owners of the site that is being characterized and those that set and enforce regulations. Practitioners are typically contractors (e.g., consulting firms or individuals)
6 SEEING INTO THE EARTH that provide characterization services to clients that have a site-specific need. In most situations the consulting (service) firms that do near-surface characteriza- tion are small (an order of magnitude or more smaller than similar service firms in the oil industry) and are often specialized in their applications and techniques. Practitioners should have an in-depth knowledge of the various methods in- volved theory, data acquisition, and processing and interpretation and an un- derstanding of how to design and carry out multidisciplinary characterization surveys. However some contractors that would like to use noninvasive tools may find it difficult to stay abreast of developments in one specialty, let alone multiple fields or integrated design and interpretation. The gap between the state of knowl- edge and the state of practice in noninvasive methods may be due, in large part, to a lack of awareness on the part of the practitioners. Scientists and engineers need to place greater emphasis on com municating information about noninvasive tools and techniques and their recent advances to practitioners. Limitations of time, money, and personnel make it difficult for contractors to stay current about the latest tools and techniques being developed in universities and government laboratories. This problem can be addressed by efforts that make such information more easily located and readily available. The rapid growth of use of the Internet and the World Wide Web helps to solve the distribution problem (see Box 6.4~; the challenge is to develop a process and mechanisms whereby unbiased assessments of new developments can be validated and posted in a timely fashion. Competition (by bidding) for characterization jobs, compounded by regula- tory pressures and legal liability, can discourage the adoption of new tools and techniques unless contractors (1) have access to documentation of the methods'
NONTECHNICAL ISSUES 117 applicability and acceptability, (2) have information to help them persuade cli- ents that the benefits will justify the costs, and (3) can get the training they need to implement the new methods. These issues could be addressed by development of an aggressive continuing education program to distribute information about the capabilities and use of the new tools and techniques. However, to be effective in the competitive environment in which near-surface contractors operate, deliv- ery of the continuing education programs must be independent of time and loca- tion. Again, the Internet and the World Wide Web offer opportunities for new approaches to continuing education. Clients, practitioners, and regulators have varying levels of need to under- stand the science and technology underlying the various physical, chemical, and biological measurements that can be made to investigate the shallow subsurface (see Box 6.5~. To bridge the possible differences in scientific and educational backgrounds, it is important to communicate what is actually measured, how it relates to the desired parameter, and what the probability of success will be. In this way, expectations are appropriately adjusted, and the best noninvasive methodist can be selected to achieve the desired goal. For example, GPR was used with limited success in an attempt to locate pieces of ValuJet Flight 592 that crashed in May 1996 and was buried in the muck of the Florida Everglades. Investigators expected to locate metal pieces; however, GPR does not measure
8 SEEING INTO THE EARTH metal directly. Instead, GPR responds to changes in electrical properties (dielec- tric and conductivity). The success of GPR depends on how it is applied, how the results are interpreted, and whether what GPR measures can be related success- fully to the desired measurement goal (in this example, metal pieces). The committee encourages government agencies and professional societies to form partnerships in long-term efforts to distribute and share information on the capabilities and recent developments of noninvasive characterization methods. Possibilities include the following: · Develop a series of "handbooks," organized according to characterization methods, that document their applicability and limitations and provide sources of information about the latest tools and techniques. · Develop simplified decision support materials that practitioners can use to identify the most appropriate and most modern techniques to consider in solving a particular problem. · Support the establishment of an on-line resource center where informa- tion about new tools and techniques can be distributed efficiently. · Encourage development of continuing education programs that utilize the latest advances in distance learning and on-demand access to information. The users (clients) of the results of noninvasive subsurface characterization are seldom geoscientists or engineers. Results of noninvasive characterization are inherently nonunique and sometimes cannot address certain classes of subsurface characterization requirements (e.g., contaminant concentrations). The users' ex- pectations of unique and definitive answers often make the results of subsurface characterization seem suspect. This suspicion can be reinforced when results are presented with realistic error (accuracy) estimates, statements of nonuniqueness, and assessments of resolution. This problem requires effort from all parties to understand, educate, and communicate effectively. Geoscientists and engineers performing noninvasive site characterizations should strive to understand the purpose and potential application of the characterization and attempt to present the results in a form that is understandable and applicable by the users. Users likewise should attempt to bridge the gap by being aware of the limita- tions and uncertainties associated with subsurface characterization. Because most of today' s problems require multidisciplinary solutions, more cross-disciplinary education is necessary. Although research areas have become highly specialized, practitioners require a general knowledge of many disciplines. They also should understand the importance of knowing and using structured design and decision-making processes, and they should be able to codify and defend the thought processes used to arrive at a particular decision. The educa- tional system should meet both needs the narrow, in-depth focus of the re
NONTECHNICAL ISSUES 119 searcher and the general, multidisciplinary need of the practitioner. There is a need to inform regulators, decision makers, and the public about the capabilities and limitations of noninvasive methods. Efforts are needed to examine the effectiveness of the following in address- ing many of the educational concerns: (1) university curricula and research pro- grams; (2) continuing education programs, particularly using distance learning technologies; and (3) public outreach programs. REFERENCES American Society for Testing and Materials (ASTM), 1997. Provisional Standard Guide for Expedited Site Characterization of Hazardous Waste Contaminated Sites, ASTM: PS 85-96. Altshuler, T. W., A. M. Andrews, R. E. Dugan, V. George, M. P., and D. A. Sparrow, 1995. Demon- strator performance at the unexploded ordnance advanced technology demonstration at Jefferson Proving Ground (Phase I) and implications for UXO clearance, IDA Paper F-3114, Institute for Defense Analyses, Alexandria, Virginia. Butler, D., E. Cespedes, K. O'Neill, S. Arcone, J. Llopis, J. Curtis, J. Cullinane, and C. Meyer, 1998. Overview of science and technology program for JPG Phase IV, Proceedings of the UXO Forum 98, Anaheim, California. Dorn, G. A., 1998. Modern 3-D seismic interpretation, The Leading Edge 17(9), 1262-1272 Environmental Protection Agency (EPA), 1997. Expedited Site Assessment Tools for Underground Storage Tank Sites: A Guide for Regulators, EPA Office of Underground Storage Tanks, EPA- 510-B-97-001, Washington, D.C. Federal Facilities Policy Group, 1995. Improving Federal Facilities Cleanup, Council on Environmen- tal Quality and Office of Management and Budget, Washington, D.C. (wwwl.whitehouse.gov/ WH/EOP/OMB/html/miscdoc/iffc-2.html). Freeze, A., and J. Cherry, 1989. What has gone wrong?-A guest editorial, Groundwater 27(4). General Accounting Office (GAO), 1995. Federal Hazardous Waste Sites: Opportunities for More Cost-Effective Cleanups, GAO/T-RCED-95-188, Washington, D.C. Joint Unexploded Ordnance Clearance Steering Group, 1997. Unexploded Ordnance Clearance: A Coordinated Approach to Requirements and Technology Development, Report to Congress, Of- fice of the Under Secretary of Defense (Acquisition and Technology), March 1997. Miller, R. D., S. E. Pullan, J. S. Waldner, and F. P. Haeni, 1986. Field comparison of shallow seismic sources, Geophysics 51, 2067-2092. Miller, R. D., D. W. Steeples, and M. Brannan, 1989. Mapping a bedrock surface under dry alluvium with shallow seismic reflections, Geophysics 54, 1528-1534. National Research Council (NRC), 1996. Barriers to Science: Technical Management of the Depart- ment of Energy Environmental Remediation, National Academy Press, Washington, D.C. NRC, 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization, National Academy Press, Washington, D.C. National Transportation Safety Board (NTSB), 1997. Protecting Public Safety Through Excavation Damage Prevention, Safety Study NTSB/SS-97/01, Washington, D.C., 106 pp. Olhoeft, G. R., 1992. Geophysics Advisor Expert System (version 2.0): U.S. Geological Survey Open- File Report 92-526, 21 pp. and floppy disk. Shuirman, G., and Slosson, J.E., 1992. Forensic Engineering: Environmental Case Histories for Civil Engineering and Geologists, Academic Press, San Diego, California, 296 pp. U. S. Army Environmental Center (USAEC), 1994. Unexploded ordnance advanced technology dem- onstration program at Jefferson Proving Ground (Phase b, Report No. SF]M-AEC-ET-CR-94120, U.S. Army Environmental Center, Aberdeen Proving Ground, Maryland.
