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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
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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
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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.
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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
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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
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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
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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
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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
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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)
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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'
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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
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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
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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.
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Site Characterization of Hazardous Waste Contaminated Sites, ASTM: PS 85-96.
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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.
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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.
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tal Quality and Office of Management and Budget, Washington, D.C. (wwwl.whitehouse.gov/
WH/EOP/OMB/html/miscdoc/iffc-2.html).
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Cost-Effective Cleanups, GAO/T-RCED-95-188, Washington, D.C.
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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.
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Engineering and Geologists, Academic Press, San Diego, California, 296 pp.
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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.
Representative terms from entire chapter:
noninvasive characterization
