A	United States
Environmental Protection
m % Agency
EPA 600/S-15/239 | September 2015
Innovative Research for a Sustainable Future
Research Summary
EPA Technical Support Centers (TSC): FY14 Lessons Learned
David S. Burden
EPA/ORD/NRMRL/GWERD
1.0 Introduction
John L. McKernan
EPA/ORD/NRMRL/LRPCD
Felicia Barnett
EPA/ORD/OSP/Region 4
Making Data Useful: Distilling Research Results for the EPA User and Stakeholder Community
The EPA user and stakeholder communities are continually challenged to implement best practices based on the most
up-to-date and pertinent data and tools available. However, it is impractical to expect every user/stakeholder to be able
to find, evaluate, choose and apply the latest research from EPA, academia, and the commercial sector to the site
characterization, feasibility studies, remedy implementation, and performance monitoring problems at their sites. EPA
alone publishes thousands of research papers and summary documents every year; the academic and commercial
communities publish as many or more documents potentially useful for the user community. Hundreds more pertinent
methods, models, tools, and databases are available. No regulator or site manager has the time to sift through that
torrent of data, extract the potentially applicable information, and translate it into actionable intelligence applicable to
solving specific problems at their particular site.
EPA's Technical Support Centers (TSC) included in ORD's Safe and Healthy Communities (SHC) Research Action Plan fill
the need for supplying subject-matter experts to continually assess state-of-the-art research and practices and channel
this information to users in both direct applications (i.e., site-specific technical support) and general applications (i.e.,
technical transfer activities such as technical guidance documents, conferences, or workshops). The TSCs are charged
with providing solutions by:
• Linking EPA (and other) Research to Agency Decision-makers
Applying Best Practices to Real World Field Application
Channeling Feedback from Field Application to Research Communities
Technical Support Center Clients
Federal, State and Local Regulators
Government and Private Sector Site and Project Managers
Tribal Organizations
Environmental Organizations
Community Action Groups
Feedback/
Research
Research
Applied
Science/Field
Implementation
Technical
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In 1987, the Technical Support Centers were established as part of the Technical Support Project (TSP) under an
agreement between Office of Research and Development (ORD), Office of Solid Waste and Emergency Response
(OSWER), and the EPA Regional Offices.
The TSP goal is to provide Regional Remedial Project Managers, Corrective Action Staff, and On-Scene Coordinators with
a diverse set of readily-accessible resources for technical assistance.
Components of the TSP technical support system include:
•	Regional forums
o Ground Water Forum
o Engineering Forum
o Federal Facilities Forum
•	Technical Support Centers
•	OSWER Environmental Response Team
There are three main TSCs in the SHC Research Action Plan directly accessible to EPA Project Managers, each with
specific areas of specialization:
Ground Water
Technical Support Center
Engineering
Technical Support Center
Site Characterization
and Monitoring
Technical Support Center
Engineering TSC
ORD Lab and Office Locations

Newport, OR
Du uth. MN
Narragansett, Rl
~T.
Edison, NJ
Corvallis, OR
Grosse lie, Ml
Cincinnati. OH
Washington, DC
RTP, NC
Atlanta. GA
Ada, OK	Athens. GA
Las Vegas, N V
Ground Water TSC
Gulf Breeze. FL
Site Characterization
and Monitoring TSC
This Research Summary provides a concise overview using examples to show how the TSCs conduct technical support
and technical transfer activities and serve as conduits from research to field application, and back to research.
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2.0 Materials and Methods
Gathering, Organizing, and Distributing the Pertinent Data
TSC EPA and contractor personnel are continually reading the latest research and applications publications, talking to
researchers and vendors, conducting hands-on lab and field research, and attending conferences and training sessions
to absorb and analyze the latest ideas and approaches.
The TSCs then distill these ideas and approaches into "best practices" - the sum of current knowledge on how, what,
why, and when - and deliver these to end users through:
Site-Specific Technical Guidance
•	Site Activity Review Memoranda
•	Conference Calls/Emails
•	Site Visits and Meetings
•	Model Reviews and Guidance
Technical Transfer
•	Training, Workshops, Conferences, Expert Panels
•	Issue Papers, Fact Sheets, Technical Guidance Documents
3.0 Results and Discussion
This Results and Discussion section provides six case studies - two from each of the three TSCs (Ground Water Technical
Support Center, Engineering Technical Support Center, and Site Characterization Technical Support Center)-to
exemplify and summarize the variety of TSC approaches that contribute to fulfilling the TSP mission.
Ground Water Technical Support Center (GWTSC)
In Situ Chemical Oxidation
The Issue:
In situ chemical oxidation (ISCO) is becoming one of the most widely used
remedial technologies for use at EPA hazardous waste sites. Chemical oxidation
is effective for degradation of many of the most common environmental
contaminants, can enhance mass transfer (making the contaminants more
accessible and easier to degrade) and is applicable in both soil and ground
water. Common applications of ISCO include reducing contaminant mass and
concentrations in soil and ground water, reducing contaminant mass flux from
source areas to downgradient pump-and-treat systems, and reducing
anticipated cleanup times required for natural attenuation and other remedial
options.
Why is Action Required?
Reliable and accurate sampling and analytical techniques are essential so that resultant data are representative of field
conditions during ISCO remediation. Performance monitoring of ISCO, as with any remedial technology, is important to
provide both real-process monitoring and post-treatment monitoring for treatment success. Real-time process
monitoring with immediate feedback for guiding oxidant injection approaches, evaluating reagent distribution, assessing
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Technical Support Center|3
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potential for redistribution of the contaminant plume due to injection activities, and accelerating deployment schedules
is crucial for assuring remedial effectiveness, efficiency, and timeliness.
However, ground water samples taken during
or soon after ISCO treatment to assess
contaminant degradation may contain some
of the oxidant employed as well as any
remaining contaminant. These samples
containing both oxidant and contaminants
are called binary mixtures, and may be
problematic to properly analyze. The
remaining oxidant may continue to oxidize
contaminants in the samples, may adversely
affect analytical procedures and instruments,
and the binary mixture may not be
representative of subsurface conditions (i.e.,
not in equilibrium). Some preservatives that
are used to neutralize any remaining oxidant
may impact ground water quality, and
dilution of samples to lower oxidant
concentration may reduce contaminant
detection limits to unacceptable ranges.
Therefore EPA researchers have investigated the theoretical foundations of problems related to analysis of binary
mixtures, tested approaches to resolving sampling and analytical problems with these mixtures in the laboratory and
field, and presented the lessons learned through technical presentations, journal articles, and an EPA Research Brief.
What Perspectives are Presented to improve Understanding of the Issue?
Groups of environmental engineers, analytical chemists, hydrogeologists, and remediation specialists are involved in the
research, laboratory and field testing, and technical transfer activities so that the ensuing lessons learned and
recommended approaches would be useful for a wide range of regulatory and laboratory/field personnel for making
decisions related to sampling and analysis of ISCO sites.
Who are the End Users, and How Will They Use the Results of This Research?
End users for this research are regulators, sampling personnel, and analysts, who can use this information to determine
whether ISCO site samples were taken, preserved, and analyzed properly so that the data are representative of field
conditions, and suitable for making site remediation decisions.
Lessons Learned, and Recommended Methods and Practices
Analytical problems related to binary mixtures of contaminants and oxidants are relevant and significant for a large
number of sites and studies (i.e., bench-scale and pilot-scale studies) where ISCO is used. However, these analytical
problems can be avoided by assessment of the risk/benefit calculus of analysis of binary mixtures, proper assessment of
oxidant presence in environmental samples, and appropriate preservation of samples for analysis. Further details can
be found in the Ground Water Issue Paper Ground Water Sample Preservation at In-Situ Chemical Oxidation Sites -
Recommended Guidelines (EPA/600/R-12/049).
Figure 1. Permanganate concentrations in 40 mL VOA vials.
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Ground Water Flow Spreadsheet Tool (3PE - 3 Point Estimator)
The Issue:
Efficient and effective characterization, remedy implementation and performance monitoring for contaminated ground
water depend on a detailed understanding of ground water gradients and velocity. Hydraulic head values from
monitoring wells are used to estimate gradients and velocities near the wells. Values from three wells can be used to
solve the "three point problem" for determining the flow direction and groundwater velocity in homogenous isotropic
and anisotropic aquifers.
Why is Action Required?
It is useful to be able to quickly calculate ground
water flow directions and velocities from ground
water head values taken from sets of wells (i.e., sets
of three wells in triangles) across a site in order to
assess current site conditions, plan sampling
approaches, distribute injected reagents properly,
etc. While many software tools exist for using
ground water hydraulic head values to estimate
ground water gradients and velocities, there is a
need for user-friendly, inexpensive software that
can be used in the office and in the field.
What Perspectives are Presented to Improve Rgure 2 Hydrau|jc Gradjent and Ve|odty Vectors graphjc output from 3pE
Understanding of the Issue?
GWERD/GWTSC scientists and contractors, including hydrogeologists, ground water flow modelers, and software
developers collaborated to develop a Microsoft Excel™ based spreadsheet tool (3PE - 3 Point Estimator) that makes it
simple and convenient for anyone familiar with the basics of spreadsheets and ground water flow to enter or import
hydraulic head values or pressure transducer data.
A user's guide for the software explains the mathematical foundations of the three point problem, the approaches used
for solving the problem, and how to use the software step by step throughout the whole process of entering data,
performing the calculations, and outputting the results in tables, graphics, and as input to other programs such as the
Golden Software GRAPHER™ program (e.g., to produce rose diagrams), or as an ArcGIS™ layer that can be imposed over
geo-referenced base maps.
Who are the End Users, and How Will They Use the Results of This Research?
End users include regulators, contractors/consultants, researchers, and students needing simple, free software to
quickly assess ground water gradients and velocities. Primarily, the 3PE tool would be used in conjunction with other
site data evaluation tools to develop conceptual and mathematical models of ground water parameters and behavior to
guide site investigation, remedy design and implementation, and performance monitoring. The 3PE tool would be
useful at any site, but it is particularly useful on sites where intensive and expensive ground water flow modeling
exercises are not warranted.
Lessons Learned, and Recommended Methods and Practices
An important part of the TSCs' outreach efforts involve finding or developing tools to help environmental decision-
makers assimilate, analyze, interpret and apply the large volumes of data that are produced from investigations at
hazardous waste sites. However, tools are only useful (and used) when they fit into the needs and workflow of potential
Hydraulic Gradient and Velocity Vectors
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-> Hydraulic Gradient Direction
¦> Groundwater Velocity Direction
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00 MO 400 600 800 toon UOO 1400 1600 iBOO
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users. Only by continually interacting with end users (e.g. regulators, site investigators) through both site-specific
technical support and technical transfer can GWTSC and the other TSCs develop tools that meet the needs and provide
solutions for end users.
Engineering Technical Support Center (ETSC)
Biotransformation of Dimethylarsinic Acid
The Issue:
Many millions of pounds of dimethylarsinic acid [DMA(V)], an organic arsenic
compound, and its salts have been released into the environment due to their
use as pesticides and herbicides. Also, there is evidence that
biotransformation processes in the environment, which can readily transform
arsenic compounds, can be significant sources of organic arsenicals.
Why is Action Required?
Toxicity and environmental effects of both organic and inorganic arsenic compounds can be significant, so it is important
to understand the arsenic biogeochemical cycle when evaluating site conditions and potential remediation efforts for
arsenic-contaminated sites.
What Perspectives are Presented to Improve Understanding of the Issue?
The Engineering Issue Paper Biotransformation of Dimethylarsinic Acid (from the Engineering TSC) provides a concise
overview of the chemical properties, toxicity, aerobic and anaerobic biotransformation, and fate and transport in the
environment of DMA(V), based on perspectives from chemists, microbiologists, soil scientists, and engineers.
Who are the End Users, and How Will They Use the Results of this Research?
This Engineering Issue Paper is for use by Remedial Project Managers (RPMs), On-Scene C oordinators (OSCs),
contractors, and other state or private remediation managers, to help make decisions about site characterization,
remediation, monitoring, and potential human and environmental health effects for arsenic-contaminated sites.
Lessons Learned, and Recommended Methods and Practices
Pentavalent arsenic species are generally immobile in oxic environments, so maintaining an oxic environment may aid in
reducing transport of arsenic in the environment.
However, under anoxic conditions, DMA(V) is demethylated to inorganic arsenic; both inorganic As(V) and As(lll) can be
produced. Trivalent arsenic species (both organic and inorganic) are generally both more toxic and more mobile than
pentavalent arsenic species (organic and inorganic).
Therefore, all potential arsenic species produced from biotransformation processes should be considered in the remedy
selection process when altering a site's oxidation/reduction environment and pH.
Passive Samplers for Investigations of Air Quality
The Issue:
Volatile organic compounds (VOC) and semivolatile organic compounds (SVOC), such as vinyl chloride, benzene, and
other contaminants, can move as vapors from contaminated soil or ground water into air at the surface, and into
O OH
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Dimethylarsinic Acid
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structures such as homes, offices, and other occupied buildings. This movement of the volatile compounds from the
subsurface into buildings is known as vapor intrusion (VI).
Why is Action Required?
Development of reliable, less invasive passive alternatives provides certain advantages in making VI site-related
decisions over active sampling techniques. Subsurface VI from contaminated soil or ground water to indoor air is a
significant hazard at many hazardous waste sites, particularly at RCRA sites where commercial operations are ongoing.
Also, contaminants can move through the soil off-site, or with ground water as that water moves off-site, and then move
up into buildings that are not on the hazardous waste site. Exposure to the vapors can cause adverse health effects, and
the vapors may not be detectable by odor, so monitoring is necessary for protection of human and environmental
health.
It is important to be able to accurately and precisely measure these volatile compounds in indoor or outdoor air to
determine to what degree VI may be a problem at a location. There are several methods for sampling for VI intrusion
issues; one method that has become widely used is passive sampling (i.e., without being collected by pumping or other
active method), which uses a solid sorbent in a container with openings of known dimensions that allow VOC vapors to
pass through at a known rate. However, as with all sampling methods, passive sampling requires adherence to a
detailed sampling protocol to ensure accurate and useful results.
What Perspectives are Presented to Improve Understanding of the Issue?
The Engineering Issue Paper Passive Samplers for Investigations of Air Quality:
Method Description, Implementation, and Comparison to Alternative Sampling
Methods (from the Engineering TSC) compares passive sampling techniques and
devices to active sampling techniques and devices, presents the basic theory of
how passive sampling devices work, designing and implementing a passive
sampling program, data quality objectives, and interpretation of passive
sampling results.
Who are the End Users, and How Will They Use the Results of This Research?
This Engineering Issue Paper is for use by Remedial Project Managers (RPMs),
On-Scene Coordinators (OSCs), contractors, and other state or private remediation
managers to understand how passive samplers work, how they can be best deployed, and how the resulting data can be
interpreted in terms of making site-related decisions for protection of human and environmental health.
Lessons Learned, and Recommended Methods and Practices
Lessons learned include:
•	Passive samplers are capable of measuring many different kinds of VOCs and SVOCs in indoor and outdoor air.
•	Passive samplers can yield reliable, time-averaged sample concentrations with comparable accuracy and precision to
established conventional methods such as evacuated canister samples or pumped sorbent tube samples.
•	Passive samplers have the advantage of greater ease of deployment and deployment over longer time frames (e.g.,
weeks or months) than is possible with conventional canister-based methods of air sampling.
•	The sampling protocols are simple, which reduces the risk of inter-operator error, the cost of sampling, and the level
of training needed for sampling personnel.
Diffusive barrier
-Adsorbent
Figure 3. Badge-style passive sampler.
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•	Passive samplers operate without risk of power loss, clogging, or leaks that may affect active sampling methods.
•	The adsorption rate, or 'sampling rate', is the most critical variable for accurately determining air concentrations
using passive samplers.
The EIP includes a detailed discussion of recommended methods and practices for designing and implementing a passive
sampling program, development and implementation of data quality objectives, and interpretation of passive sampling
results.
Site Characterization and Monitoring Technical Support Center (SCMTSC)
ProUCL - Statistical Software for Data Analysis to Support Site Remediation
The Issue:
Site characterization, remedy selection, and remedy
performance monitoring often generate large data sets to
be used in making site-related decisions. Critical
assessment, interpretation, and proper use of these data
sets involves sophisticated statistical analyses that few users
of the data sets have in-depth training in. While software
packages to help make the statistical techniques more
accessible are commonly available, such packages can be
complex, not directly oriented to the particular problems
involved in environmental sampling, and difficult to properly
use without extensive training and experience.
Why is Action Required?
Histogram Output Screen
Selected options: Group Graphs
Hrelogrom fot Cu
Reported values used tor nondetecls
Figure 4. Sample histogram output from ProUCL,
In order to help ensure that environmental data are properly analyzed, interpreted, and used by decision makers,
software tools are needed which are:
» explicitly designed to be used for common environmental data analyses,
» user friendly so that data input and analysis are straightforward, and
» simple enough that minimal training is required for effective use.
Therefore SCMTSC developed ProUCL, a free statistical software model, to meet these needs.
What Perspectives are Presented to Improve Understanding of the Issue?
ProUCL was originally developed to help address Regional personnel's concerns about a specific Superfund site. It soon
became clear that there was wide demand for such software, so SCMTSC, in conjunction with statistical experts,
programmers, and a wide variety of end users, has continued to develop ProUCL to increase its capabilities, incorporate
the latest statistical techniques, and keep ProUCL updated for current Windows versions. Feedback received from users,
and students in ProUCL training webinars, is used by ProUCL developers to continually refine ProUCL to meet user
needs.
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Who Are the End Users, and How Will They Use the Results of This Research?
Environmental decision makers, including federal and state environmental managers and contractors, environmental
consultants, and hazardous waste stakeholders use ProUCLto analyze data from their sites, and make site-related
decisions based on sound science and evaluation approaches. For example, ProUCL can be used to establish background
levels, determine outliers in data sets, and compare background and sample data sets for site evaluation and risk
assessment.
Lessons Learned, and Recommended Methods and Practices
The widespread and increasing demand for and acceptance of ProUCL by federal and state regulators, contractors,
consultants, and the environmental remediation community in general, indicates the value of providing and maintaining
ProUCL as a state-of-the-art, user-friendly software package for environmental data. SCMTSC provides continual
outreach efforts to engage the user community and promote the use of ProUCL so that best practices for site data
analysis are within the reach of all site decision makers.
Ground Water/Surface Water Interactions and Cross-Media Transfer
The Issue:
Ground water/surface water interactions are the
driving forces for cross-media transfer of
contaminants from ground water contaminant
plumes into surface water bodies such as streams or
lakes. However, it is often difficult to determine
where and when contaminants are being transferred
from ground water to surface water, because the
areas of transfer are highly heterogeneous. That is,
the specific locations where ground water moves into
surface water are difficult to find and characterize
because most of the ground water movement into
the surface water may occur through small, scattered
patches of the streambed or lakebed.
Why is Action Required?
Cross-media transfer of contaminants from ground water to surface water involves numerous regulatory issues, and so
is a major factor in design and implementation of remediation and monitoring systems for hazardous waste sites. As
noted above, characterization of these ground water/surface water interactions is difficult, and regulators and site
managers need tools to provide rapid and accurate assessments of the locations of significant ground water/surface
water interactions.
Because ground water moving into surface water is often at a different temperature from the surface water, the
locations of ground water influx can be evaluated by measuring the temperature of the water in the streambed or
lakebed where the ground water and surface water meet. Therefore SCMTSC investigated the use of temperature
anomaly measurements to evaluate ground water/surface water interactions. Specifically, SCMTSC investigated the use
of distributed temperature systems (DTS) to provide a relatively simple, accurate, and lower-cost approach to evaluate
larger areas of streambeds or lakebeds for temperature anomalies.
Fiber optic DTS provides a means to procure a continuous temperature profile along the fiber optic, so temperature
measurements can be obtained all along the fiber optic, wherever it might be laid on the streambed or lakebed. Thus
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DTS can potentially replace thousands of individual temperature sensors, and allow for surveying and monitoring
relatively large areas of streambed or lakebed.
What Perspectives are Presented to Improve Understanding of the Issue?
Site characterization to get accurate, complete, and timely data for making site-related decisions is often difficult, time-
consuming and costly. SCMTSC, in fulfillment of the TSP goal of continually distilling the best of research developments
and new approaches to make them available and practical for the end user, has evaluated research and best practice for
DTS with their geophysicists, hydrologists, engineers, and statisticians to determine how DTS can be a useful and
practical tool for assessing ground water/surface water interactions.
Who are the End Users, and How Will They Use the Results of This Research?
Potential users of DTS include both field workers and managers concerned with site characterization, monitoring, and
remediation of sites where cross-media transfer of contaminants from ground water to surface water is a potential or
actual hazard.
For example, SCMTSC is providing support at the Clearview Landfill, Darby Township, Pennsylvania for investigating
ground water/surface water interactions/discharges at the site in order to locate and measure potential/probable
ground water seeps into the creek using DTS. The data obtained can be used to assist in the site ecological evaluation,
understand contaminant fate and transport, and evaluate remediation effectiveness.
Lessons Learned, and Recommended Methods and Practices
Although the importance of understanding ground water/surface water interactions for assessing sites and protecting
human and environmental health has long been recognized, the limitations in the available investigation tools has made
detailed characterization difficult and time-consuming. A major factor has been the high resource cost for finding the
areas where ground water moves into streams and lakebeds. SCMTSC has sought out solutions for this bottleneck by
using cross-disciplinary approaches to find real-time environmental sensors and tools such as DTS which have been
effectively implemented in other areas (geothermal energy, smart grids, process plants, etc.). DTS can be used with
dynamic work strategies and rapid sampling to improve site-related decision-making efficiency and effectiveness at sites
where ground water/surface water interactions occur.
4.0 Conclusions and Recommendations
The user community for the Technical Support Centers is large
and diverse, with needs ranging from basic explanations and
demonstrations of concepts, tools, and approaches for
characterization, remedy implementation, and monitoring, to
highly complex analyses and model development for guiding
remediation of heterogeneous sites and complex contaminant
distributions. Providing useful and effective technical support
on such a wide range of subjects and users requires the TSCs to
•	Maintain a continual open dialogue with the user
community to understand user needs
•	Practice continual improvement to keep technical support
efforts at state of the art levels
Excellence in Technical Support
Know user needs
Stay "state of the art"
Use cross-disciplinary approaches
Focus on critical factors
Provide user-friendly technical support
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•	Take a cross-disciplinary, broad perspective approach to understanding and solving technical problems
•	Focus on the crucial factors that drive site-related technical and regulatory decisions
•	Package and deliver technical support in readily accessible user friendly ways, in a variety of formats
5.0 References
Ko, S., S.G. Huling, and B. Pivetz. Ground Water Sample Preservation at In Situ Chemical Oxidation Sites - Recommended
Guidelines. EPA Ground Water Forum Issue Paper. U.S. Environmental Protection Agency, National Risk Management
Research Laboratory, R.S. Kerr Environmental Research Center, Ada, OK. (EPA/600/R-11/109)
USEPA. Technical Support Project: Technical Support Centers.
http://www.epa.gov/superfund/remedytech/tsp/tscs.htm
USEPA. Obtaining Technical Support for Superfund, RCRA, and Brownfields Site Issues.
http://www.epa.gov/superfund/remedytech/tsp/download/tech_support_center_assist.pdf.
USEPA. Statistical Software ProUCL 5.0.00 for Environmental Applications for Data Sets with and without Nondetect
Observations, http://www2.epa.gov/land-research/proucl-software.
USEPA. Passive Samplers for Investigations of Air Quality: Method Description, Implementation, and Comparison to
Alternative Sampling Methods. EPA/600/R-14/434. December 2014.
USEPA. Biotransformation of Dimethylarsinic Acid. EPA/600/R-14/219. December 2014.
Keywords
Technical Support Project, Technical Support Centers, Ground Water Technical Support Center, Engineering Technical
Support Center, Site Characterization and Monitoring Technical Support Center, In Situ Chemical Oxidation,
Dimethylarsinic Acid, Passive Samplers, ProUCL, Cross-Media Transfer
Contact
David S. Burden, Ph.D.
US EPA Office of Research and Development
Ground Water Technical Support Center
(580) 436-8606
burden.davidffiepa.gov
www2.epa.gov/research
John L. McKernan, Sc.D.
US EPA Office of Research and Development
Engineering Technical Support Center
(513) 569-7415
mckernan.iohn@epa.gov
www2.epa.gov/research
Felicia Barnett
US EPA Office of Research and Development
Site Characterization and Monitoring Technical Support Center
(404) 562-8659
barnett.felicia@epa.gov
www2.epa.gov/research
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