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Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization (1997)

Chapter: 5 TESTING REMEDIATION TECHNOLOGIES

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Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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5
Testing Remediation Technologies

Many major U.S. industries, such as the pharmaceutical and automotive industries, have standard protocols for testing new product performance. Such protocols are lacking in the hazardous waste site remediation industry. This lack of protocols contributes to the difficulties that remediation technology developers face in trying to convince potential clients that an innovative technology will work. Lacking performance data collected according to a standard protocol, clients may hesitate to choose an innovative remediation technology because of the uncertainty in how the innovative technology will perform in comparison to a conventional technology. The types of data collected for evaluating remediation technology performance vary widely and are typically determined by the preferences of the consultant responsible for selecting the technology, the client, and the regulators overseeing remediation at the contaminated site. From the perspective of the client and the service providers who are interested in solving the immediate problem in a cost-effective manner, such a site-specific strategy is justified. However, from the broader perspective required for remediation technology development and testing, the performance and cost data needed to meet site-specific objectives are often insufficient to extrapolate the results from one site to another.

As a result of the lack of standard procedures for remediation process testing, many of the early attempts at soil and ground water cleanup, especially at complex sites, served as poorly planned and very costly national experiments. Expensive remediation systems were installed to clean up sites with very little understanding of the mechanisms controlling their performance. The results of these efforts were evaluated to try to gain a better understanding of mechanisms governing remediation, but such evaluations were complicated by the lack of stan-

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

dardized data sets (National Research Council, 1994; EPA, 1992). In some cases, remediation systems, such as soil vapor extraction (SVE), proved successful despite the limited understanding. In other cases, however, such as with pump-and-treat systems, tens of millions of dollars were spent at individual sites to install systems that later proved unable to meet cleanup goals (National Research Council, 1994; EPA, 1992).

Since the early 1990s, the Environmental Protection Agency (EPA) and other federal agencies have increasingly recognized the limitations of existing data on remediation systems and have taken steps to improve the consistency of data collection at contaminated federal sites. In 1995, the Federal Remediation Technologies Roundtable, a group of lead agency representatives involved in site remediation, issued guidelines for the collection of remediation cost and performance data at federal facilities (Federal Remediation Technologies Roundtable, 1995). Nevertheless, no standard process exists for data collection and reporting at privately owned contaminated sites, and the degree to which the Federal Remediation Technologies Roundtable guidelines are applied at federal facilities is unclear. The challenge for remediation technology development is to provide a framework and an infrastructure so that the individual benefits accruing to service providers and clients at specific sites, both federal and private, are gradually aggregated. Aggregation and critical review of data gathered according to standard protocols at numerous sites are essential for ensuring that the data are widely accessible to other technology developers and users, so that the success stories are not derived solely from anecdotes or unpublished reports.

This chapter describes a set of general principles that should be applied when testing performance of remediation technologies. It outlines the types of data needed to prove the performance of different classes of technologies, how to choose an appropriate test site for a remediation technology, and how to determine the amount of additional testing required to evaluate whether a technology tested at one site is applicable at another site. It also recommends ways that policymakers and others can encourage standardization in the collection of data on remediation technology performance.

DATA FOR PROVING TECHNOLOGY PERFORMANCE

Commercialization is the process of increasing use of a technology to solve a particular problem. Those who are considering use of an innovative remediation technology early in the commercialization process must decide whether the benefit (performance) of the technology is commensurate with its risk (failure to attain regulatory requirements). Generally, the user's greatest concern is having to do more: apply the technology over a longer period, implement an additional technology, or abandon the innovative technology and apply a conventional one. Therefore, to commercialize a remediation technology, the technology developer

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

must convince prospective users that the innovative technology will cost effectively solve their problems with minimal risk (cost) of failure.

There are two approaches to minimizing the risk of using an innovative technology. The first is to guarantee performance. Such a guarantee requires assumption of financial risks or of residual liability. If the technology fails, the seller of the technology assumes the cost of meeting the remedial goals or the liability for noncompliance. To be able to offer the guarantee, the seller must have sufficient assets to make the guarantee credible. Given their limited financial resources, this is not possible for many technology developers. The second approach to minimizing the risk of using an innovative technology is to provide enough data so that the user is confident in the ability of the technology to provide the desired result. The data must be sufficient to verify the technology—that is, to prove its performance under a specific set of conditions with assurance of data quality.

The data required to verify performance include proof that the technology works under field conditions and proof that the technology will be accepted by regulators. In order to prove that the technology works to the satisfaction of potential clients and regulators, the technology developer will need evidence to answer two fundamental questions:

  1. Does the technology reduce risks posed by ground water or soil contamination? That is, what are the levels of risk reduction achieved by implementing the technology?

  2. How does the technology work in reducing these risks? That is, what is the evidence proving that the technology was the cause of the observed risk reduction?

As described in Chapter 4, remediation technologies reduce risk by decreasing the mass, concentration, mobility, and/or toxicity of contaminants in the subsurface. Direct measurements showing decreases in one or more of these parameters are essential for proving technology performance, but they are not sufficient to prove that the technology was responsible for the observed decrease in contamination. For example, contaminant concentrations in ground water may decrease for a variety of reasons, including sorption of contaminants by soil or aquifer solids, dilution due to natural mixing with uncontaminated ground water, biodegradation by native soil microbes, or chemical reactions with substances naturally present in the subsurface. A cause-and-effect relationship between application of the remediation technology and observed decreases in contamination must be established by collecting data to answer the second question, how does the technology work? Without answering this question and understanding the mechanisms responsible for performance of the technology, the technology design cannot be optimized, and the technology cannot be reliably transferred to other sites. In the past, technology tests have rarely been performed using protocols that answer this second question. This failure to gather evidence to explicitly

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

link performance to remedial process has slowed regulatory acceptance and site-to-site transfer of innovative remediation technologies.

Demonstrating Risk Reduction Achieved by the Technology

To answer the question of whether the remediation technology works in reducing health and environmental risks, field tests are required to determine the reductions in contaminant mass, concentration, toxicity, and/or mobility achieved after application of the technology. Demonstrating reductions in all four risk measures—mass, concentration, toxicity, and mobility—is not necessary. Rather, the technology evaluation should provide two or more types of data leading to the conclusion that the technology has succeeded in decreasing one or more of the four risk measures. Which measure is appropriate depends on the remediation end points that the technology is designed to achieve.

Contaminant concentrations in the field following application of a remediation technology are readily determined by analyzing ground water samples from monitoring wells and soil samples from soil cores according to standard procedures. Likewise, decreases in contaminant mobility can be documented through standard tests that analyze contaminant leachability (although these tests are sometimes misapplied). However, documenting reductions in contaminant mass and toxicity is more challenging.

Quantifying contaminant mass in the subsurface, both before and after remediation, can present a significant challenge due to the complex distribution of contaminants among different phases (dissolved, sorbed, nonaqueous liquid, or solid) in both the horizontal and vertical directions. Contaminant mass is typically estimated based on concentration data from monitoring wells and soil core samples and on an estimation of the volume of contaminated material (mass equals concentration multiplied by volume). For example, in a field experiment to evaluate intrinsic remediation of petroleum hydrocarbons, the mass of hydrocarbons remaining in the subsurface at any given time was estimated by integrating concentration data from a network of monitoring wells over the contaminated area (Barker et al., 1987). However, although contaminant concentration and contaminant mass are closely linked and although contaminant mass is usually estimated based on measures of concentration, a reduction in contaminant concentration does not always signal a reduction in contaminant mass. Contaminant concentrations may decrease due to a manifestation of rate-limiting mass transfer phenomena or due to dilution with uncontaminated waters, while the total mass of contaminants remains essentially the same. The uncertainties associated with estimating total contaminant mass based on concentration data from discrete sampling locations at a heterogeneous site are often not reported.

Determining the toxicity of contaminants in the field is likewise difficult because of the cost and complexity of the studies required to link contaminant exposure to human health and ecological damage. The actual toxicity of contami-

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

nants to both human health and ecosystems can be measured only through long-term studies that assess the health and ecological impacts of contaminants. Such studies exist for some contaminants but not for others (see Chapter 4). An alternative for contaminated material that has been solidified or stabilized is to use leaching tests that analyze for toxic compounds in water that might leach through the solidified or stabilized material. Test methods for assessing the toxicity of leaching water include the extraction procedure toxicity test and the toxicity characteristic leaching procedure (EPA, 1989).

Methods for measuring decreases in contaminant mass and concentration differ somewhat depending on whether the remediation technology is designed to stabilize or contain contaminants, or to extract or destroy them. For stabilization and containment technologies, decreases in mobile contaminant mass should be determined by analyzing the amount of contamination available for transport to zones of natural ground water flow; for all other types of technologies, decreases in mass should be determined by analyzing the amount of mass remaining within the zone of remediation. For stabilization and containment technologies, effects on contaminant concentration should be determined by analyzing concentrations outside the zone of remediation, while for other types of technologies concentration or mass decreases should be measured inside the zone of remediation.

Demonstrating How the Technology Works

The second type of evidence needed to prove innovative remediation technologies—the cause-and-effect evidence—comes from data that link the basic risk reduction criteria with the technology being tested. The goal of collecting these data is to show that the physical, chemical, and biological characteristics of the site change in ways that are consistent with the processes initiated by the technology. Table 5-1 outlines, for each remediation technology subgroup identified in Chapter 3, the environmental conditions that can be monitored to establish the cause-and-effect linkage between remediation and the applied technology.

Carrying out many of the tests summarized in Table 5-1 will require the use of experimental controls. Experimental controls compare the differences in various site characteristics with and without application of the technology. The selection and use of controls in remediation technology testing are perhaps the most important factors in determining the success or failure of the experiment. Without good controls, it will be impossible to determine whether changes in site characteristics were a result of the technology application or of some other cause. Table 5-2 describes several control strategies that can be used to help determine which observed changes are a result of the remediation technology and which are not. Box 5-1 provides an example of experimental controls used to test a bioventing process.

The complexities of the subsurface and remediation technologies make computer models a useful tool for analyzing and generalizing results of remediation

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

TABLE 5-1 Data to Establish Cause-and-Effect Relationship Between Technology and Remediation

Stabilization/Solidification/Containment Technologies

Biological Reaction Technologiesa

• Mechanism for decreased leachability

- Formation of insoluble precipitate

- Strong sorption/bonding to solids

- Vitrification, cementing, encapsulation

• Stoichiometry and mass balance between reactants and products

• Increased concentrations of intermediate-stage and final products

• Integrity of stabilized material

- Completeness of processes throughout treated region

- Compressive strength of solidified material

- Reaction to weathering (e.g., wet/dry and freeze/thaw tests)

- Reaction to changes in ground water chemistry

- Microstructural analyses of composition

• Increased ratio of transformation product to reactant

• Decreased ratio of reactant to inert tracer (or, in general, decreased ratio of transformable to nontransformable substances)

• Increased ratio of transformation product to inert tracer (or, in general, increased ratio of transformation product to nontransformable substances)

• Geochemical conditions that affect leachability of stabilized materials (pH, Eh, competing ions, complexing agents, organic liquids, etc.)

• Relative rates of transformation for different contaminants consistent with laboratory data

• Increased number of bacteria in treatment zone

• Increased number of protozoa in treatment zone

• Increased ratio of immobile- to mobile-phase contaminants

• Increased inorganic carbon concentration

• Changes in carbon isotope ratios (or, in general, in stable isotopes consistent with the biological process)

• Fluid transport properties of solidified material

- Permeability

- Porosity

- Hydraulic gradient across monolith

- Rate of water flow through monolith

• Decreased electron acceptor concentration

• Increased rates of bacterial activity in treatment zone

• Bacterial adaptation to contaminant in treatment zone

• Indicators of liquid/gas flow field consistent with technology (i.e., indication that treatment fluids have been stabilized or contained region is blocked)

• Indicators of liquid/gas flow field consistent with technology (i.e., indication that flow through the successfully delivered to the contaminated area

a For further details about proving performance of biological reaction technologies, see National Research Council, 1993.

experiments. Whenever possible, computer simulation models should be used to plan and evaluate experiments to establish the link between observed remediation and the technology. Computer simulation models use mathematical equations to track the mass of contaminants in the subsurface. They describe how the contaminant mass is partitioned among aqueous and nonaqueous phases; how much is transported with the ground water, as a non aqueous-phase liquid (NAPL), or as a gas; how much reacts with other chemicals and with aquifer materials; how much degrades by biological or chemical reactions; and how each of these processes is affected by the introduction of a remediation technology. Simulations can be used in many ways in remediation technology evaluation. One approach is to use models to predict the behavior of contaminants under natural conditions and compare it with contaminant behavior during and following application of the remediation technology. A second approach is to use models to evaluate the sensitivity of soil or ground water quality variables to introduction of the remediation technology by simulating how those variables differ under natural and remediation conditions. A third approach is to use the model to quantify the uncertainty in various types of data, allowing the user to evaluate the trade-offs between information, cost, and uncertainty when using different types of data. A final approach is to use models to determine the optimal experimental design to maximize information content of data while minimizing cost and uncertainty.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

Chemical Reaction Technologies

Separation/Mobilization/Extraction Technologies

• Stoichiometry and mass balance between reactants and products

• Increased concentration (mass) of contaminant in outflow stream

• Increased concentrations of transformation products

• Decreasing mass of contaminants remaining in subsurface consistent with mass extracted in outflow stream

• Increased concentrations of intermediate-stage products

• Increased mass removal per unit volume of transport or carrier fluid

• Increased ratio of transformation product to reactant

• Increased ratio of contaminants in carrier fluid to aqueous-phase contaminants

• Decreased ratio of reactant to inert tracer (or, in general, decreased ratio of transformable to nontransformable substances)

• Increased ratio of contaminants in carrier fluid to non-aqueous-phase contaminants

• Increased ratio of transformation product to inert tracer (or, in general, increased ratio of transformation product to nontransformable substances)

• Observed movement of injected carrier fluids (flushing amendments or injected gases) or tracers in carrier fluids•

• Relative rates of transformation for different contaminants consistent with laboratory data Changes in geochemical conditions, consistent with treatment reactions (pH,Eh,etc.)

• Spatial distribution of contaminants prior to, during, and after remediation

• Indicators of liquid/gas flow field consistent with technology (i.e., indication that treatment products have been successfully delivered to the contaminated material)

• Indicatiors of liquid / gas flow field consistent with technology

affected by the introduction of a remediation technology. Simulations can be used in many ways in remediation technology evaluation. One approach is to use models to predict the behavior of contaminants under natural conditions and compare it with containment behaviour during and following application of the remediation technology. A second approach is to use models to evaluate the sensitivity of soil or ground water quality variables to introduction of the remediation technology by simulating how those variables differ under natural and remediation conditions. A third approach is to use the model to quantify the uncertainty in various

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

Table 5-2 Experimental Controls for Improving Technology Evaluation

Method

Purpose

Collection of baseline data

Collection of accurate baseline data is the most basic type of experimental control and is essential to the success of the technology test. Without excellent baseline data, it will not be possible to develop an accurate comparison of conditions before and after application of the technology.

Controlled contaminant injection

In controlled contaminant injection, ground water from the site is spiked with the contaminants under consideration and re-injected into the aquifer. Therefore, the initial makeup, mass, location, and distribution of contaminants in the subsurface are known. Under these controlled conditions, the contaminant can be more easily and accurately tracked and monitored to determine the effect of the remediation technology.

Conservative tracers

Conservative tracers do not undergo the reactions associated with in situ reactive technologies. However, they are subject to a number of nonreactive processes that flow paths, flow rates, mixing, affect and retention of contaminants. Therefore, conservative tracers can be used to distinguish remediation resulting from the treatment process from that which occurs naturally.

Partitioning tracers

Partitioning tracers provide an indication of the total mass and spatial distribution of nonaqueous-phase liquids (NAPLs). They can be used to compare NAPL mass and spatial distribution prior to technology application with NAPL mass and distribution after remediation. Thus, they allow evaluation of NAPL removal and spatial patterns using a nondestructive technique.

Sequential start-and-stop testing

By alternating technology application and resting periods, the contaminant's fate can be observed under both natural conditions and remedial conditions. In this way the effects of the technology can be separated from remediation caused by naturally occurring processes. In addition, the start-and-stop approach can be used to distinguish between dynamic and equilibrium processes.

Side-by-side and sequential application of technologies

Side-by-side testing of two or more technologies at one site can be used to compare the capabilities of different technologies for the same hydrogeologic and contaminant setting. As an alternative, technologies can be applied sequentially at the same site to determine the marginal effectiveness of one technology over another.

Untreated controls

Untreated controls can help distinguish between technology-enhanced remediation and intrinsic remediation that occurs as a result of naturally occurring processes. The use of untreated controls is analogous to side-by-side testing with one of the remediation technologies being intrinsic remediation.

Systematic variation of technology's control parameters

The effect of changes in a technology's operating conditions on remediation can be determined by systematically changing control parameters. Ideally, this approach would be used to identify a technology's optimal operating conditions.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

BOX 5-1 Use of Experimental Controls: Evaluating Bioventing at Hill and Tyndall Air Force Bases

At Hill Air Force Base in Utah and Tyndall Air Force Base in Florida, spills of JP-4 jet fuel have caused soil and ground water contamination. To demonstrate the capabilities of bioventing, the U.S. Air Force Center for Environmental Excellence sponsored field tests to evaluate the technology, which delivers oxygen to contaminated soils to stimulate contaminant biodegradation (Hinchee and Arthur, 1991; Hinchee et al., 1992).

Prior to the field tests at Hill and Tyndall, laboratory tests had shown that the addition of both moisture and nutrients may be needed to support continued contaminant biodegradation in bioventing systems. The field tests at both sites used experimental controls to quantify the effects of moisture and nutrient additions. At Hill, the bioventing system's parameters were sequentially varied to determine bioventing's effectiveness under different operating conditions. By operating the bioventing system first with no added moisture or nutrients, then adding moisture, then adding nutrients, researchers found that moisture addition stimulated biodegradation, but nutrient addition did not. At Tyndall, researchers used two side-by-side test cells to analyze the effects of moisture and nutrients. One cell received moisture and nutrients for the duration of the study. The other cell received neither moisture nor nutrients at the outset, then moisture only, then moisture and nutrients. In this case, no significant effect of either moisture or nutrients was observed. Researchers surmise that the different results at the two field sites were most likely due to contrasting climatic and hydrogeologic conditions. The fact that the two sites reacted differently indicates the need for additional controlled experiments to better gauge the effects of moisture and nutrients on bioventing.

types of data, allowing the user to evaluate the trade-offs between information, cost, and uncertainty when using different types of data. A final approach is to use models to determine the optimal experimental design to maximize information content of data while minimizing cost and uncertainty.

In proving that a technology is responsible for documented remediation and establishing the extent and rate of remediation attributable to the technology, a single type of evidence alone will usually not be sufficient. The larger the body of evidence used, and the more varied the converging lines of evidence, the stronger the case for the performance of the remediation technology.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×
Stabilization, Solidification, and Containment Technologies

When evaluating the performance of stabilization and solidification technologies, the most important data are those documenting immobilization of the contaminants. Thus, as indicated in Table 5-1, samples that document the mechanisms for decreased leachability (such as formation of an insoluble precipitate or cemented monolith) provide evidence that the stabilization technology has worked. Related to this will be data documenting the integrity of the stabilized material, such as data that demonstrate that the stabilization process is complete throughout the treated region or, for solidified material, data that document the permeability, porosity, and rate of fluid flow through the solidified monolith. Other data, such as the solidified material's compressive strength or its reaction to weathering tests, are an indication of the materials' long-term stability.

Stabilization, solidification, and containment technologies sometimes require certain environmental conditions to succeed. Properties such as pH, Eh, and concentrations of competing ions should be documented to show that geochemical conditions favor the stabilization processes at work. In addition, data can be collected to document changes in fluid flow fields that are consistent with the technology design.

Box 5-2 provides a case example of the types of data gathered to document performance of one type of solidification/stabilization process in a successful field test. This example provides a useful model for tests of solidification, stabilization, and containment technologies at other sites.

Biological and Chemical Reaction Technologies

In the process of transforming or immobilizing contaminants, biological and chemical reactions alter the soil and ground water chemistry in ways that can be documented to prove that the reaction processes are taking place. The observed chemical changes should follow directly from the chemical equations that define reactants and products and their ratios. Thus, many cause-and-effect data for biological and chemical reaction processes are derived from mass balance relationships defined by governing chemical equations. Increased concentrations of transformation products, concentrations of intermediate and final products, and ratios of reactants to products all can be used to demonstrate performance of biological and chemical reaction technologies. Geochemical conditions should also change in ways that can be predicted from the governing chemical equations. For example, ignoring microbial growth, the stoichiometric relationship used to relate oxygen (O2) consumption and carbon dioxide (CO2) production to biodegradation of petroleum hydrocarbons is

Cn Hm+ (n + 0.25m)O2→­nCO2 + (0.5m)H2O

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

BOX 5-2 Proving In Situ Stabilization/Solidification of Polychlorinated Biphenyls (PCBs) at the General Electric Co. Electric Service Shop, Florida

International Waste Technologies (IWT)/Geo-Con conducted a field study to demonstrate the ability of their stabilization/solidification process to treat PCB-contaminated soils (EPA, 1990). The IWT in situ process mixes water and a cement-based proprietary additive with the contaminated soil to immobilize and contain PCB contaminants in a solidified, leach-resistant monolith. A series of analyses was performed on samples from the demonstration site to document stabilization/solidification of the PCBs in the soil. The table below describes the types of data that were collected to (1) document immobilization of PCBs and (2) establish the cause-and-effect relationship between the stabilization/solidification process and the documented remediation. A careful comparison of treated and untreated soils, along with a careful analysis of baseline conditions, provided the experimental controls for this evaluation.

Data Objective

Type of Data

Document PCB stabilization

Leach tests showing immobilization of PCBs

 

Stabilized contaminant content of solidified soil

Link PCB immobilization to cementation

Decrease in permeability of solidified material as compared to untreated soil

 

High unconfined compressive strength of solidified material

 

Documented integrity of solidified material under wet/dry weathering tests

 

Microstructural analyses—optical microscopy, scanning electron microscopy, and X-ray diffraction—showing that the solidified mass is dense, homogeneous, and of low porosity, with no compositional variations in the horizontal and vertical directions.

where CnHm represents a particular petroleum hydrocarbon. This equation can be used to determine how much O2 will be consumed and how much CO2 produced from the degradation of 1 mole (or 1 gram) of hydrocarbon or, conversely, how much hydrocarbon is degraded per mole of O2 consumed or CO2 produced. In other words, for every mole of O2 consumed per minute, 1/(n+0.25m) mole of

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

hydrocarbon is degraded per minute; similarly, for every mole of CO2 produced per minute, 1/n mole of hydrocarbon is degraded. Researchers from the U.S. Geological Survey (USGS) have used the above equation, along with field measurements of the rates of change of O2 and CO2 gas concentrations, to determine the rate of biodegradation of hydrocarbons at a site in Galloway Township, New Jersey (Lahvis and Baehr, 1996). The rates of biodegradation the USGS researchers computed based on O2 consumption and on CO2 production were in close agreement: the rate based on O2 gas flux was 46.0 g per m2 per year, while the rate based on CO2 gas flux was 47.9 g per m2 per year. The researchers used a mathematical transport model calibrated to the observed O2 and CO2 gas data to determine the O2 and CO2 gas fluxes and used a weighted average based on the concentrations of the various hydrocarbons found at the site to determine the stoichiometric coefficients.

Conservative tracers (see Table 5-2) are particularly useful when evaluating remediation systems that use biological or chemical reactions. Conservative tracers are not affected by biological and chemical reactions associated with the remediation technologies but are affected by all other nonreactive processes. Thus, they can be used to evaluate in situ reactions by documenting a decreased ratio of chemical reactant, or an increased ratio of transformation product, to tracer. For example, helium can be used in bioventing to show that O2 loss is due to consumption by microorganisms rather than dispersion.

In recent years, considerable effort has focused on understanding the microbial reactions that degrade certain soil and ground water contaminants. In a 1993 report, the National Research Council outlined in detail the evidence required to document that bioremediation processes are occurring in the field (National Research Council, 1993). This evidence, in addition to using stoichiometric equations as described above, includes the number of bacteria, number of protozoa, rates of bacterial activity, and a range of other data that link observed ground water remediation with biodegradation processes.

Box 5-3 provides an example of data gathered to confirm a biological reaction process, in situ bioremediation of chlorinated solvents using methanotrophic bacteria. This example can serve as a model for other field tests of biological and chemical reaction processes.

Separation Technologies

Data collection for proving separation technologies should focus on documenting the transfer of contaminants to the more mobile liquid or gas phase and the level of increase in contaminant removal efficiency. The data should also show that the two (increased contaminant mobility and increased removal) are related. The most important piece of evidence is an increase in the concentration of contaminant in the fluid or gas extracted from the subsurface. This increase

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

should coincide with a decrease in the mass of contamination remaining in the subsurface.

The success of separation technologies depends on delivering the carrier fluid to the subsurface contaminants. Thus, tracking the observed movement of injected fluids (such as flushing amendments in NAPL recovery or gases in air sparging) will be useful in linking contaminant mass transfer and removal with the arrival of the carrier fluids. Also, because many separation technologies involve altering the fluid flow field, documenting changes in fluid flow properties, such as fluid pressures and flow paths, that are consistent with the technology will be useful.

Boxes 5-4 and 5-5 provide examples of test protocols used to demonstrate two types of separation technologies (in situ mixed region vapor stripping and in situ cosolvent flushing) at two sites. These protocols can serve as models for future tests of separation technologies.

Determining the Level of Testing Required

The types of evaluations shown in Table 5-1 include theoretical modeling, laboratory experiments, and field tests. Which level of testing will be required depends on the complexity of the technology, but in general the strongest proof of technology performance derives from multiple lines of evidence demonstrating with laboratory and field data the theoretical concepts underlying the design of the technology.

Figure 5-1 shows how a technology would be proven under ideal circumstances: starting with theoretical concepts, proving these concepts in laboratory experiments and then in field tests, and then demonstrating the technology at full- scale in the field. Some technologies, such as reactive barriers for in situ ground water remediation (see Box 5-6) have evolved through this linear, hierarchical process, from theory, to laboratory testing, to field testing, to full-scale application. For other commonly used technologies, however, the development process has been neither linear nor unidirectional. For example, early air sparging systems were designed based on field pilot tests, rather than detailed laboratory experiments, to prove efficacy and determine the extent of air flow, but the technology has matured based on careful laboratory studies to determine factors that influence the direction of air flow in the subsurface (see Box 5-7). SVE technology was applied in the field before detailed laboratory testing was conducted to fine-tune design procedures (see Box 3-2 in Chapter 3). Whether laboratory testing will be necessary before a technology is applied in the field depends on the complexity of the technology. For example, the design basis for SVE systems is fairly simple, involving induction of air flow to volatilize contaminants; detailed laboratory testing was not necessary prior to field testing because the processes controlling volatility are already well understood. On the other hand, the chemical reactions employed in reactive barriers are more complex and are highly sen-

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

Box 5-3 Proving In Situ Bioremediation of Chlorinated Solvents at Moffett Naval Air Station, California

Researchers at Stanford University conducted a field study to demonstrate engineered in situ bioremediation of chlorinated solvents by methane-oxidizing bacteria (Roberts et al., 1990; Semprini et al., 1990). In this experiment, known quantities of vinyl chloride, trichloroethylene (TCE), cis-dichloroethylene (cis-DCE), and trans-dichloroethylene (trans-DCE) were injected into a densely monitored, well-characterized aquifer. A series of biostimulation and bioremediation experiments was performed to document the engineered degradation of the organic solutes. Biostimulation by injection of methane -and oxygen-containing ground water was used to stimulate the growth of indigenous bacteria.

Results showed that biostimulation caused concurrent decreases in concentrations of the organic contaminants. The table below describes the types of data that were collected to (1) document remediation and (2) establish the cause-and-effect relationship between the methane-oxidizing bacteria and the documented remediation. In these experiments, controlled contaminant injections, conservative tracers, untreated test areas, systematic variation of operating parameters, and start-and-stop testing were used as controls.

Data Objective

Type of Data

Document reduction in quantity of contaminants

Reduction in organic contaminant concentrations

 

Reduction in organic contaminant mass determined from the ratio of mean normalized concentration of organic contaminant to bromide tracer for quasi-steady-state conditions; a comparison of breakthrough of organic contaminants before and after biostimulation; and a mass balance comparing amounts of contaminant injected to amount removed at extraction wells

Link contaminant disappearance to indigenous methane-oxidizing bacteria

Decrease of chlorinated organic contaminant concentrations coinciding with methane utilization.

 

Production of a transformation intermediate for trans-DCE

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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Data Objective

Type of Data

 

Increase in organic contaminant concentrations and disappearance of transformation intermediate when methane addition stopped

 

Relative transformation rates consistent with laboratory data (vinyl chloride degraded faster than trans-DCE, which degraded faster than cis-DCE, which degraded faster than TCE)

 

No degradation of TCE observed in zone where no methane was present to support bacterial growth

 

No evidence of anaerobic conditions (i.e., no intermediate products of anaerobic degradation)

 

Presence of indigenous methanotrophic bacteria

sitive to geochemistry; laboratory testing was essential in this case to define the parameters that control technology performance.

Whether or not a technology is laboratory tested prior to field application, the strongest proof of technology performance comes from multiple lines of evidence leading to the same conclusions. The evidence gathered should build a consistent, logical case that the technology works based on answering the questions of whether the risks from contamination decrease after application of the technology and whether the technology is responsible for the risk reduction achieved, as shown in the examples in Boxes 5-2, 5-3, 5-4, and 5-5.

Developing protocols that specify the general types of data that should be gathered for different technologies is possible, as shown in Table 5-1. However, the amount and specific types of data needed are highly specific to the individual technology and to the site where it is being tested. The data must minimize uncertainties associated with describing the complex heterogeneities of the subsurface environment, contaminant distribution, processes that control fate and transport of contaminants, and processes that control performance of the remediation technology. As a consequence, the details of the data collection plan and the extent of data collection vary for each new technology and each test of that technology in a new environment. The data collection plan should follow basic principles of experimental design, as outlined by Steinberg and Hunter (1984) and Cochran and Cox (1957). The data report should include a summary of the evaluation methods

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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Box 5-4 Proving In Situ Mixed-Region Vapor Stripping in Low-Permeability Media at the Portsmouth Gaseous Diffusion Plant, Ohio

Researchers from Oak Ridge National Laboratory, Michigan Technological University, and Martin Marietta Energy Systems, Inc., conducted a full-scale field experiment to demonstrate the removal of volatile organic compounds (VOCs) from dense, low-permeability soils (West et al., 1995; Siegrist et al., 1995). The demonstration site, at a Department of Energy gaseous diffusion plant in Portsmouth, Ohio, had been used as a disposal site for waste oils and solvents. The silty clay deposits beneath the site were contaminated with VOCs at concentrations ranging up to 100 mg/kg. In addition, the shallow ground water was contaminated with trichloroethylene (TCE) at concentrations above the drinking water standard.

The remediation process, termed mixed-region vapor stripping (MRVS), mixes the soils in place using rotating augers. Compressed gases are injected into the mixed soils, and the VOCs are stripped from the subsurface. The off gases are captured at the surface and treated. The study included a set of replicated tests to evaluate the relative efficiencies of ambient and heated air for stripping VOCs. The following table describes the types of data that were collected to (1) document in situ stripping of VOCs from the dense, low-permeability layers and (2) establish the cause-and-effect relationship between the MRVS process and the documented remediation. A conservative tracer and systematic variation of operating parameters (heat) were used as controls.

used to prove technology performance similar to the examples in Boxes 5-2, 5-3, 5-4, and 5-5. The ranges of uncertainty for each type of data should be specified.

SELECTING A TEST SITE

In selecting a test site for an innovative remediation technology, technology developers usually confront one of two situations: either the developer will have a potential client and will need to demonstrate the technology at that client's site, or the developer will not have a client and will need to seek a test site available through various government programs. In the first case, the developer must face the question of how to select a location at the client's contaminated site to field test the technology. In the second case, the developer will need to apply to a government program to try to obtain a test site.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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Data Objective

Type of Data

Document reduction in VOCs

• Reduction in soil VOC concentrations

• Reduction in VOC mass in soils determined by analysis of off gases

• Rate of VOC mass reduction determined from analysis of off gases

Link VOC reductions to in situ stripping

• TCE, 1,1,1-trichloroethane, and 1,1-dichloroethylene were present at same ratios in both off gas and soil matrix

• Soil, air and off-gas temperature increased concurrent with injection of heated air

• Absence of soil vapor pressure and temperature changes in undisturbed soil surrounding mixing zone, suggesting that VOCs in mixing zone were removed rather than being forced into surrounding soils

• Tracer studies revealed that the process did not homogenoize the soil and caused limited translocation of soil, suggesting that the VOCs in the mixing zone were removed rather than redistributed.

Testing at a Client's Site

For technology developers with an established client, the key to selecting a test location is to thoroughly characterize the contaminated site and then choose a test location that achieves a balance between being representative of conditions at the site and being simple enough that uncertainties in site hydrogeologic conditions do not overpower analysis and interpretation of technology performance data. There are four principal components to site characterization: (1) identification of contaminant sources, (2) delineation of site hydrogeology, (3) quantification of site geochemistry, and (4) evaluation of biogeochemical process dynamics. The types of data gathered for each of these components of site characterization will depend in part on the remediation technology being evaluated and in part on the types of contaminants present at the site. The end result of the site characterization will be a conceptual model showing locations of contaminant

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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Box 5-5 Proving In Situ Cosolvent Flushing at Hill Air Force Base

At a Hill Air Force Base site contaminated with jet fuels and chlorinated solvents disposed of in the 1940s and 1950s, University of Florida and EPA researchers conducted a pilot-scale field study to demonstrate enhanced contaminant solubilization by in situ cosolvent flushing (Annable et al., in press; Rao et al., in review). The researchers installed a test cell in a 2-m-thick contaminant source zone containing a large mass of contaminants present as NAPLs. The test cell dimensions were 5 m x 3 m x 10 m deep. The cell was underlain by a deep clay confining unit, so that the test zone was hydraulically isolated from the rest of the aquifer.

Over a 10-day period, the researchers injected a total of 40,000 liters of a cosolvent mixture (70 percent ethanol, 12 percent pentanol, and 18 percent water) through four injection wells. Following the cosolvent injection, the researchers flushed the test cell extensively with water to remove the cosolvents. The cosolvent fluids, along with solubilized NAPL, were extracted through three wells. A network of 72 multilevel samplers allowed monitoring of the internal dynamics of the flushing process between the injection and extraction wells.

The researchers collected a variety of data, shown in the table below, to establish multiple line of evidence for NAPL removal and to link NAPL removal with the cosolvent flushing process. As predicted in earlier laboratory studies, cosolvent flushing in the field test removed more than 95 percent of several NAPL constituents and more than 85 percent of total NAPL mass. The unextracted NAPL mass was highly insoluble and contained no measurable concentrations of target contaminants. Sequential applications of a pump-and-treat system and the cosolvent flushing system, as well as comparisons of the movement of conservative tracers and partitioning tracers before and after remediation, were used as experimental controls.

Data Objective

Type of Data

Document reductions in NAPL mass and contaminant concentrations

Decreased concentrations of NAPL constituents in soil cores

 

Decreases in NAPL constituent concentrations in ground water samples

 

Increased concentrations of NAPL constituents in extraction fluids

 

Decreased retardation of partitioning tracers after treatment, indicating extraction of NAPL mass

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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Data Objective

Type of Data

 

Consistency of mass removal estimates from all of the above evaluations; all showed greater than 85 percent removal of NAPL mass

 

Monitoring of contaminants, cosolvents and tracers outside the test cell, demonstrating the effectiveness of hydraulic containment

Link NAPL removal to cosolvent flushing

Comparison of NAPL removal achieved with a conventional pump-and-treat system and that achieved with cosolvent flushing; extensive flushing with a pump-and-treat system did not lead to decreased contaminant concentrations in produced fluids

 

Large rise in dissolved NAPL concentrations coincident with arrival of cosolvents in samples taken at the multi-level monitoring wells and extraction wells

 

Maximum NAPL constituent concentrations in extracted fluids consistent with predictions based on controlled laboratory studies of NAPL solubilization with the cosolvent mixtures.

sources and plumes and site hydrogeology (see Figure 5-2), along with tables showing site biogeochemistry and important biogeochemical processes. The data collected during site characterization must be sufficient to provide a baseline for assessing (1) whether the technology works and (2) how it works.

The first component of site characterization—the identification of contaminant sources—includes evaluation of the types of contaminants in the subsurface and their properties (reactivity, solubility, volatility, and mobility). It also includes delineation of the spatial distribution and measurement of the concentrations of contaminants in the subsurface, with particular attention to the distribution of contaminants among the aqueous, nonaqueous, solid, and sorbed phases. This step of site characterization will be the same regardless of the type of technology being tested, because a thorough documentation of contaminant distribution is essential for designing the technology installation and understanding the

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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A column experiment to evaluate the kinetics and chemistry of surfactant flushing of hydrophobic organic contaminants from aquifer sediment. Courtesy of Richard Luthy, Carnegie Mellon University.

technology's performance. The disposal or spill history at the site and site hydrogeology play important roles in determining the distributions of contaminant sources and the sizes and shapes of plumes generated from these sources. Since detailed historical records are often not maintained, delineation of contaminant sources is the most challenging problem in site evaluation. Especially difficult to map are NAPL sources, because conventional soil coring methods cannot provide a complete picture of NAPL distribution. However, recently developed tracer techniques offer considerable promise for mapping NAPL mass distribution using nondestructive techniques (see Box 5-8 for details).

The second component of site characterization—delineation of site hydrogeology—involves developing a model of site geologic units and quantifying hydrogeologic properties that influence ground water and contaminant movement. This step in site characterization will be the same regardless of the type of remediation technology being tested, because a detailed understanding of ground water and contaminant movement is essential for designing pilot tests of any remediation technology. Included in this stage of site characterization are an

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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Figure 5-1 Usual hierarchical scales of technology testing. Laboratory-scale testing is used to identify and quantify factors that affect process performance. Field testing is used to determine whether the technology can work under real world conditions and to modify designs based on laboratory results. Full-scale implementation is needed before a final verdict can be reached on the effectiveness of a technology.

SOURCE: Modified, with permission, from Benson and Scalfe (1987) © 1987 by A. A. Balkema.

evaluation of site geology; characterization of stratigraphy, including types, thicknesses, and lateral extent of aquifer units and confining units; measurement of depth to ground water, ground water recharge and discharge points, hydraulic gradients, and preferential flow paths; quantification of aquifer physical properties, including hydraulic conductivity, porosity, and grain size distribution, as well as the variations in these properties with location; and quantification of vadose zone properties, including gas and water permeability.

The third component of site characterization—quantification of aquifer geochemistry—involves measuring any chemical properties of the ground water that will affect the fate of the contaminants and performance of the remediation technology. Thus, if technology performance is sensitive to changes in pH, Eh, dissolved oxygen concentration, organic carbon concentration, or any other geochemical parameter, then these parameters must be carefully documented before remediation begins.

The fourth component of site characterization—evaluation of biogeochemical process dynamic—includes analyzing geochemical characteristics of the soil

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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Box 5-6 Development of Passive-Reactive Barriers Based on Laboratory Studies

The concept that zero-valent metals, such as iron, can dehalogenate chlorinated compounds and thus might be useful in environmental cleanup first appeared in the scientific literature in the early 1970s. However, this concept was not extended to the cleanup of contaminated ground water until approximately 1990, when researchers at the University of Waterloo began laboratory and field studies to determine whether zero-valent metals might be applicable to cleanup of contaminated ground water (Gillham, 1995). Their idea was to emplace zero-valent iron in a permeable underground wall ahead of a plume of contaminated ground water, so that any chlorinated compounds in water passing through the wall would be dechlorinated by the iron (see Chapter 3) (Gillham et al., 1994).

In laboratory batch and column experiments designed to mimic the ground water environment and in a field study, the Waterloo researchers demonstrated chlorine mass balances of 100 percent, showing that the contaminants were dechlorinated by zero-valent iron (Orth and Gillham, 1996). Early testing also included determination of dechlorination reaction rates in laboratory studies with a number of halogenated methanes, ethanes, and ethenes to demonstrate the potential applicability of this method to a range of contaminants and to document reaction requirements (Gillham and O'Hannesin, 1994). Key experiments showed that metallic iron creates low redox conditions necessary for the dechlorination of the chlorinated compounds and that iron solid is needed for the reaction to proceed. These experiments have led to several full-scale applications of the technology (see Box 3-5 in Chapter 3 for one example).

Prior to installation of a permeable, iron-containing reactive wall, treat-

and aquifer materials, mineralogy, sorption potential of solid materials, presence or absence of indegenous microbes and their biodegradation potential, nutrient conditions, substances that may inhibit or compete with biodegradation, and any other biogeochemical properties that might play a role in remediation and in the natural fate of contaminants in the absence of remediation. Design of a data collection plan for understanding biogeochemical process dynamics will vary with the type of remediation technology being tested, because different types of technologies will be influenced by different biogeochemical processes. However, for all technologies, enough data on these processes should be gathered to allow an understanding of the fate of contaminants in the absence of remediation so that

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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ability studies are used to identify design parameters for the wall. Treatability studies for the first full-scale applications of the technology were expensive, consisting of laboratory column experiments using site ground water, variable mixtures of sand and iron, and varying water velocities, followed by similar studies in the field using above-ground canisters. As experience and acceptance of the technology have increased, the treatability study protocol has been streamlined to consist generally of column experiments with 100 percent reactive iron and ground water from the site (ETI, 1995). While the testing and design phase prior to the first full-scale installation (see Box 3-5) required nearly three years, application at a second site in the same state required only a few months of testing. In some instances, for ground water with low contaminant concentrations, mixtures containing half sand and half reactive iron are tested. The laboratory columns are monitored for contaminants and reaction products with time until reaching steady state. Pseudo-first-order rate coefficients for each contaminant are determined from the steady-state concentration distributions. System designers then determine the required residence time in, and thus the thickness of, the reactive wall based on these rate coefficients (Thomas et al., 1995). At large sites, pilot-scale studies may also be needed to modify and improve the design. In all of these studies, temperature and pH of the actual field conditions must be mimicked, because these parameters can significantly affect transformation rates. Designers must also characterize the site's hydrogeologic conditions adequately to ensure that the reactive wall will capture the contaminant plume.

The relatively rapid commercialization of passive-reactive barriers was due in part to the well-planned laboratory and pilot tests preceding the first commercial application. Research at independent laboratories provided independent confirmation of rapid contaminant transformation rates, and the well-planned pilot test demonstrated success in the field.

the effect of remediation can be assessed. That is, the data must allow a determination of the extent to which any reductions in contaminant concentration and mass can be attributed to intrinsic biogeochemical processes that occur in the absence of remediation. Estimating biogeochemical process parameters is an uncertain exercise at many sites. The parameters may vary both spatially and over time due to microscale variations in environmental and geochemical properties.

Once the site is adequately characterized, a test plot should be chosen that represents conditions at the site but is simple enough to minimize uncertainties in evaluating technology performance. Ensuring that the test plot is reasonably representative of the site is essential for the scaleup stage of the technology test. If

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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Laboratory-scale testing to evaluate the transport of microorganisms used for biological treatment in an aquifer. Courtesy of Roger Olsen, Camp Dresser & Mckee.

the pilot test site is not geostatistically representative of the section of the site for which the technology is being considered, then the technology may fail during scaleup. At the same time, in the early stages of technology development, more useful information is gained by conducting tests in relatively uncomplicated geologic settings, which allow the developer to separate inherent process performance limitations from matrix complexities. Unfortunately, such simple sites are not always available, resulting in a data set that is confounded by geologic complexity. This is especially an issue for sites where the technology ''fails" its demonstration; it may be unclear whether the failure is inherent to the remediation process or is due to complex site conditions and inadequate accounting for these conditions in the design of the remediation system.

While the test area must be simple enough to allow evaluation of technology performance, at the same time it must be representative of site conditions. That is, the test volume must contain a geostatistically representative number of the geologic and contaminant features likely to be critical in full-scale project implementation. Otherwise, the uncertainty in extrapolating results from the test cell to full-scale application will be too large to allow for meaningful predictions. Failure to select a representative test area during a pilot test can often lead to unanticipated technical difficulties, less effective remediation than indicated in the pilot tests, and cost overruns when the full-scale project is initiated.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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Pilot-scale land biotreatment units used to assess biotransformation and biodegradation of PCB-contaminated sediment and sludge. Pilot-scale tests are needed to assess practical treatment rates. Courtesy of Alcoa.

A final consideration in the selection of a test location is concerns of site regulators. Obtaining regulatory approval to test technologies involving injection of substances, either treatment fluids or contaminants to be used in the test itself, can be a complex process (see Boxes 5-9 and 5-10). For example, in the case described in Box 5-10, involving selection of a site to conduct tests of multiple technologies, selecting a test site and obtaining all of the necessary regulatory permits took one-and-a-half years, much longer than project managers and the consortium of academic researchers involved in the study had anticipated.

Testing at a National Test Site

Until the mid-1990s, very few sites were available for researchers to test innovative remediation technologies in the field without first having a client interested in buying the technology. Essentially the only option was to test technologies under the Superfund Innovative Technology Evaluation (SITE) Program, which has limited scope and funding. (In fact, funding for the SITE Program was

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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BOX 5-7 Development of Air Sparging Based on Field Applications Followed by Detailed Studies

As with many remediation technologies, the initial application of air sparging was based on a rudimentary understanding of the technology and was field derived. Air sparging design was based primarily on field pilot testing to prove efficacy and determine the extent of air flow. However, air sparging has rapidly progressed from an empirical field practice to an ongoing research area.

Designers of air sparging systems have benefited from the lessons learned from the development of SVE: that air flow is the key to successful treatment and that air flow in the subsurface is governed by a number of parameters. Early protocols for testing air sparging systems used monitoring well parameters such as pressure readings, dissolved oxygen concentrations, contaminant volatilization rates, and water table rise as indicators of the effective radius of the sparging systems. While these parameters provide a general indication of where the injected air is traveling, smaller sampling intervals and the use of tracer gases have shown that air flow is complex, not predictable, and not as uniform as would be indicated by monitoring well data. In fact, recent studies have shown that even with conventional pilot testing and design, air sparging performance can be highly variable, Johnson et al. (1997) conducted pilot and full-scale tests of air sparging in a gasoline-contaminated shallow aquifer and concluded that short-term pilot tests involving measurement of the typical parameters (dissolved oxygen concentrations, pressure readings, water table levels) used to estimate air sparging performance provided overly optimistic estimates of long-term, full-scale system performance. Based on such findings, Johnson and others have recommended that short-term pilot tests of air sparging be used to evaluate the feasibility of using the technology and to identify reasons for poor performance under test conditions, rather than to provide detailed predictions of long-term performance (Johnson et al., 1997).

Current air sparging research is focusing on improving methods for measuring and controlling air flow in saturated media. If measurement tools can be developed to determine where air travels during sparging, design of systems and predictions of performance can be more rigorous. Methods for maximizing air distribution during sparging include pulsing and multilevel sparging.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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eliminated in 1996 and reinstated in 1997 at a modest $6 million, a fraction of the cost of cleaning up one Superfund site.) In addition, only one site, the Moffett Air Force Base in California, was available for researchers to inject contaminants under controlled conditions and monitor the results of a remediation system (National Research Council, 1994).

In recent years, the federal government has made a significant effort to increase the number of test sites available on federal facilities, including sites where controlled contaminant injections are allowed for technology evaluation purposes. In 1996, the EPA issued a policy memorandum providing strong encouragement to use federal facilities as sites for demonstrating technologies (Laws, 1996). Table 5-3 lists federal programs that provide assistance to developers needing sites or other forms of support for field testing innovative remediation technologies. Some of these programs, such as the Navy's Environmental Leadership Program, guarantee full-scale use of any technology successfully demonstrated under program (EPA, 1996a). Such programs provide critical support for innovative remediation technology developers at the stage between technology development and commercialization.

While the number of test sites has increased, competition for pursuing tests under these federal programs is intense. For example, the first solicitation for technology testing to be carried out at Department of Defense sites under the Advanced Applied Technology Demonstration Facility program drew 170 proposals: only 12 of these were selected (see Box 5-11).

SITE-TO-SITE TRANSFER OF TECHNOLOGIES

Once a technology has been successfully tested at one site, the developer and potential clients will wish to determine whether the technology can be transferred to another site. In general, some degree of additional testing at the second site will be required prior to implementing the technology there. However, funds for field pilot testing are often limited, and the technology developer is often faced with the task of minimizing the amount of additional site-specific testing, while at the same time providing adequate assurance that the technology will perform as predicted at the new site. An adequate understanding of how the technology works (that is, an answer to the second question posed at the beginning of this chapter) can help to minimize site-specific pilot testing costs.

The degree of additional testing that will be required before an innovative remediation technology can be applied at the second site is primarily a function of the properties of the contaminant and the hydrogeologic setting in which it exists. In general, technologies used to treat mobile and/or reactive contaminants will require less additional testing than those used to treat contaminants with limited mobility and reactivity. Solubility and volatility are the primary factors that control contaminant mobility in soil and ground water. Reactivity is a measure of the biodegradability or chemical reactivity (via oxidation, reduction, or

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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FIGURE 5-2 Development of a conceptual model of the geologic units of a contaminated site.

precipitation) of the contaminant. The more a treatment technology makes use of a fundamental property related to contaminant mobility or reactivity, the more easily it can be transferred from one site to another for treatment of similar contaminants. Similarly, the more conducive a geologic setting is to fluid (air and/or water) flow, the more easily a new technology can be applied at that site with minimal additional testing. Permeability and degree of saturation are the two hydrogeologic factors that most affect treatability.

As discussed in this chapter, there are generally two purposes for testing the performance of innovative remediation technologies. One is to prove the efficacy of a process: Does it reduce the risks posed by the soil and/or ground water contamination? The other is to determine how the process works: Which contaminant properties does the technology make use of, and how is the process affected by hydrogeologic properties such as permeability and saturation? The higher the treatability of a contaminated site, the lower the site-specific testing requirements will be for assessing a new technology's efficacy or applicability. For example, application of SVE at a site with highly volatile contaminants in a highly permeable formation would require limited site-specific testing. On the other hand,

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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BOX 5-8 NAPL Source Zone Mapping: Use of Tracer Techniques

Locating, quantifying, and delineating NAPL source zones presents considerable difficulties and uncertainties due to the highly heterogeneous nature of NAPL distribution in subsurface zones. Identifying the nature and extent of NAPL source contamination is an essential element of site characterization and a regulatory requirement. Conventional geophysical methods used for NAPL source mapping include soil core sampling, ground water and soil gas analyses, electromagnetic resistivity tests, and ground penetrating radar techniques (Feenstra and Cherry, 1996). The most common of these are analyses of samples (soil, gas, or ground water) taken at several locations at a site. These point measurements of NAPL contaminant concentrations are spatially interpolated to estimate total NAPL mass. However, such estimates are subject to considerable uncertainties. Also, some of these techniques require destructive sampling (as in soil coring), precluding repetitive sampling at the same location.

A new experimental technique, based on the displacement of a suite of tracers through the NAPL source zone, was developed by researchers at the University of Texas (Jin et al., 1995). Data from nonreactive tracers yield information about site hydrodynamic characteristics, and the extent of retarded transport of the reactive tracers yields a measure of the NAPL volume present in the zone swept by the tracers. Multilevel samplers placed between the injection and extraction wells provide data to map the NAPL spatial distribution, and the extraction wells provide depth-and volume-integrated estimates of total NAPL volume.

The first field-scale test of the partitioning tracer technique was conducted by University of Florida researchers at Hill Air Force Base (Annable et al., in press). This test provided an integrated measure of the total volume of NAPL and its spatial distribution within an isolated test cell (3 m x 5 m x 10 m), and the tracer results were consistent with average values estimated from soil core and ground water analyses. Similar tracer tests were completed in eight other test cells as part of a coordinated study at the same site; results are expected to be released by the end of 1997.

The use of this tracer technology is in its early stages of development. As additional data from a variety of test sites are gathered, use of the technique will increase.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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BOX 5-9 State Regulatory Policies for Remediation Technology Testing

For remediation technology developers, obtaining appropriate regulatory approvals for technology testing is a major hurdle that must be overcome in order to have a chance to demonstrate the new technology under field conditions. This is an especially significant problems for in situ flushing technologies that require injection (and withdrawal) of additives such as surfactants and alcohols for enhanced extraction and for some remediation technologies requiring addition of nutrients, primary substrates, or electron acceptors. The underground injection of additives is prohibited by regulatory or procedural barriers in many states. Authority for regulation of underground injection wells is split between the states and the federal government. The EPA conducted a survey in 1995 to identify institutional barriers to remediation technologies that require some type of underground injection. The report (EPA, 1996c) reached the following conclusions:

About two-thirds of the states have allowed some sort of injection incidental to an in situ ground water remediation technology; most of these cases were for injection of nutrients for enhanced bioremediation.

Eleven states have allowed surfactant injection, mostly at Superfund sites. (One state has allowed alcohol injection since this EPA report was published; see Box 5-5 for the case study.)

No state has a direct regulatory prohibition of injection technologies for treating contaminated aquifers. A few states have policies that discourage use of injection technologies; however, most of the states have rejected most or all of the proposals received, citing a broad spectrum of concerns.

The technical merit of the proposed technology, as documented in the proposal to the state, was the key factor in the approval process.

application of a process claiming to biodegrade DDT would require significant testing.

Figure 5-3 and Tables 5-4 and 5-5 depict factors influencing treatability and show how contaminant properties and geologic setting affect treatability and the need for site-specific testing of remediation technologies. The columns in Figure 5-3 organize contaminants on the basis of high (H) or low (L) volatility, reactivity, and solubility. The rows organize geologic settings on the basis of texture and saturation. The figure shows four groups of contaminated sites: easy to treat (category I), moderately difficult to treat (category II), difficult to treat (category III),

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

Installing electrodes and treatment zones for a pilot test of electro-osmosis treatment at the Paducah, Kentucky, Department of Energy site. The pilot test was conducted by the Lasagna Consortium(TM). Courtesy of the Department of Energy.

and extremely difficult to treat with current technologies (category IV). As the difficult of treatment increases, so does the amount of site-specific testing required to prove efficacy and applicability.

Category I includes sites with highly volatile and/or reactive contaminants in highly permeable soils. Contaminated sites in this category are easy to treat primarily because volatilization or biodegradation can efficiently remove contaminant mass. Contaminants in this category include the gasoline components benzene, toluene, ethylbenzene, and xylene (BTEX); chlorinated volatile organics such as chlorinated ethenes; and alcohols. High contaminant solubility complicates in situ treatment because it causes more contaminant mass to dissolve in ground water, making contaminant volatilization more difficult. However, the high volatility and reactivity of contaminants in category I make treatment of these contaminants in homogeneous saturated aquifer formations relatively easy.

For sites in category I, determining the efficacy and applicability of a remediation process generally requires minimal site-specific testing, as shown in Table 5-5. Efficacy and applicability of a technology can often be determined from the fundamental properties of the contaminant or the site. Testing requirements for remediation technologies being considered at sites in this category are generally

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

BOX 5-10 Selecting a Test Site for Side-by-Side Technology Comparisons

The Strategic Environmental Research and Development Program (SERDP), funded by the Departments of Defense (DOD) and Energy and the EPA, has funded a program to evaluate performance of several innovative remediation technologies side by side. The first step in the program was to identify a portion of a field site where innovative technologies could be pilot tested side by side. The program stipulates that the tests be conducted at a DOD facility unless a suitable DOD site cannot be found. Despite a high level of cooperation from DOD site managers and regulatory officials, selecting a test site and obtaining all of the necessary regulatory permits took a year and a half, much longer than project managers had anticipated (C. Enfield, EPA, personal communication, 1995).

The criteria used for identifying an "ideal" test site for this project included the following: shallow ground water with a confining layer less than 15 m below ground surface in order to minimize testing costs and concern about off-site impacts; a permeable aquifer to ensure that tests can be conducted in a relatively short period of time; presence of a single component NAPL, preferably a dense NAPL (DNAPL), as residual saturation or in pools; a NAPL source area large enough to accommodate multiple test cells; a secure site with convenient access and infrastructure support cooperative site owners; and a flexible regulatory permitting process. In the early stages of the project, most candidate sites were eliminated from consideration due to one or more of the following problems: regulatory constraints and liability concerns: Inability to locate the contaminant source area with certainty; inadequate size of the source area; presence of multiple sources of c contamination or complex wastes

dictated more by site-specific design requirements than by questions of efficacy or applicability. For example, SVE technology could be assumed to be an effective remedy for treatment of trichloroethylene in a medium-grained sand, but application of SVE to such a site would require pilot testing to optimize the technology's design parameters. A technology for treating a site in this category is easily extended to other sites within this same category with contaminants for which the technology is appropriate.

Category II represents contaminated sites that are moderately difficult to treat, examples include sites with contaminants having low volatility and high solubility in geologic settings having high to moderate permeability (as in column D in Figure 5-3). Many of the contaminants in this category are also either biologically or chemically reactive; examples include phenols, glycols, methyl tertiary-butyl

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

with multiple components; and inadequate infrastructure and support services, access, or security.

The site that was ultimately selected for testing was Operable Unit 1 at Utah's Hill Air Force Base, a Superfund site. The site meets many of the criteria listed above. The Air Force is the only party liable for site contamination. The shallow, unconfined, sand-and-gravel aquifer is underlain by a thick, confining clay unit about 10 to 15 m below ground surface that extends for several hundred meters. The water table is located at about 8 m below ground surface. The aquifer is contaminated with a complex NAPL consisting of a mixture of avialation fuel (JP-4), waste solvents disposed of in two chemical disposal pits during the 1940s and 1950s, and fuels and combustion products from a fire training area. Contaminants targeted for remediation include aromatic petroleum hydrocarbons and n-alkanes from the aviation fuel and chlorinated alkenes and chlorobenzenes from the solvents. The NAPL source area and the associated dissolved plume cover an area of about 8 ha. Residual NAPL is present as a 2-m-thick smear zone just above the clay unit.

Remediation technology testing was carried out in nine test cells, each 3m x 5m. The test cells are hydraulically isolated from the rest of the aquifer. Isolation was achieved by driving interlocking sheet piles keyed into the underlying clay confining unit and sealing all the joints with grout (Starr et al., 1993). All are instrumented in essentially the same manner, with four fully screened injection wells, three fully screened extraction wells, and multilevel samplers in at least 72 locations (on a 0.7mx0.7m grid). The distribution of NAPL in each cell was carefully characterized by soil coring and partitioning tracer tests prior to testing. The remediation technologies tested in the cells are several varieties of in situ methods for NAPL extraction; the methods use either cosolvents, surfactants, steam, air, or cyclodextrin to extract the NAPLs. Enhanced solubilization and enhanced mobilization are the two methods for NAPL extraction.

ether, and naphthalenes or other polycyclic aromatic hydrocarbons having three or fewer benzene rings.

When being considered for use in treating sites in category II, innovative remediation technologies will require a moderate amount of testing, as shown in Table 5-5. Assurance of performance may be strongly indicated by fundamental properties of the contaminant (such as biodegradability) or the site (such as transmissivity to fluids), but performance cannot be predicted with certainty based on these properties. Testing is required to determine applicability, especially if chemical or biological reactivity is the basis for treatment. Testing is usually directed at identifying conditions that may limit the applicability of the technology to the site. For example, application of a bioremediation process at a site contaminated with phenol would require testing to determine that the site geo-

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

TABLE 5-3 Federal Programs Providing Support to Remediation Technology Developers

Program

Purpose

Contacts

National Environmental Technology Test Sites (NETTS) Program

Provides locations, facilities, and support for applied research, demonstration, and evaluation of innovative subsurface cleanup and characterization technologies that are candidates for restoration of Department of Defense (DOD) facilities

Dr. Mark Noll, Air Force (302) 678-8284

Ernest Lory, Navy (805) 982-1299

Advanced Applied Technology Demonstration Facility (AATDF)

Seeks to identify, demonstrate, and commercialize advanced technologies potentially useful in ground water and soil remediation at DOD facilities

Dr. Herb Ward, Rice University (713) 527-4725

Rapid Commercialization Initiative (RCI)

Provides in-kind assistance for selected companies with commercially ready environmental technologies that require demonstration and performance verification

Stanley Chanesman, Department of Commerce (202) 482-0825

Strategic Environmental Research and Development Program (SERDP)

Seeks to identify, develop, demonstrate, and implement technologies of use to the DOD in six areas, including environmental cleanup

Dr. Olufemi Ayorinde, DOD (703) 696-2118

Wurtsmith Air Force Base National Center for Integrated Bioremediation Research and Development (NCIBRD)

Allows testing of biological and other technologies for remediation of fuels and solvents; test are conducted at Wurtsmith Air Force Base

Dr. Michael Barcelona, University of Michigan (313) 763-6512

Air Force Center for Environmental Excellence (AFCEE) Innovative Technology Program

Identifies and field tests innovative environmental technologies, including remediation technologies

John Caporal, Air Force (210) 536-2394

Environmental Security Technology Certification Program (ESTCP)

Selects laboratory-proven technologies with DOD market application and moves to the field for rigorous testing

Dr. Jeffrey Marqusee, DOD (703) 614-3090

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

Program

Purpose

Contacts

Naval Environmental Leadership Program (NELP)

Selects innovative remediation technologies for full-scale application at Naval Air Station North Island in San Diego, California, and Naval Station Mayport in Jacksonville, Florida

Ted Zagrobelny, Navy (703) 325-8176

Superfund Innovative Technology Evaluation (SITE) Program

Supports bench -and pilot-scale studies of innovative remediation technologies

Annette Gatchette, EPA (513) 569-7697

 

SOURCE: Adapted from EPA, 1996a.

chemical conditions (availability of nutrients and oxygen) required for effective performance are present. For technologies being considered for sites in this category, the development of a data base showing all prior technology applications is essential to commercialization, and development of a common data collection and reporting protocol would greatly assist in expanding use of the technologies. As the data base grows, the need for site-specific testing would diminish.

Category III represents contaminated sites at which the contaminant is soluble but is neither reactive nor volatile and/or at which the geology is heterogeneous. Many sites contaminated with inorganic chemicals are in this category. As shown in Table 5-5, neither the efficacy nor the applicability of technologies for treating such sites is easily derived from the fundamental properties of the contaminant or the site. Characterizing the hydrologic and geochemical variability of the site and the influence of hydrologic and geochemical properties on contaminant retention and reaction processes is extremely difficult for category III sites. Testing at each individual site is required to prove efficacy and to determine applicability. Testing may have a number of stages, including laboratory, pilot, and full-scale, but results can be readily transferred from one stage of testing to another. As testing progresses from one stage to another, the focus changes from proof of efficacy or applicability to site-specific design.

The final category in Figure 5-3 represents sites with contaminants that are neither volatile, nor reactive, nor soluble and/or having complex geologies such as clay and fractured rock. Contaminants in this category include polychlorinated biphenyls, organochlorine and organophosphorus pesticides, and polycyclic aromatic hydrocarbons with more than three benzene rings. Such contaminants are extremely difficult to treat with existing commercial technologies because their low solubility and volatility and high sorption potential complicate their detection, analysis, and destruction or removal from the subsurface. Treatment of sites

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

Box 5-11 Technology Testing Under the Advanced Applied Technology Demonstration Facility Project

In 1993, the Department of Defense (DOD) initiated a program known as the Advanced Applied Technology Demonstration Facility (AATDF) project. The DOD budgeted $19.3 million for the project to support field testing of innovative technologies for characterization and cleanup of contaminated ground water and soil. The program is administered by a university consortium including Rice University (the lead institution), Stanford University, the University of Texas, Lamar University, Louisiana State University, and the University of Waterloo. It is supported by five major consulting firms and an advisory group including representatives from DOD and industry.

Competition for obtaining funds to support technology testing under the AATDF program has been intense. The initial solicitation yielded 170 proposals; 38 of these were selected for submission of full proposals, and 12 of these 38 were selected for funding. Funded projects include field testing of funnel-and-gate technologies for directing ground water flow into a treatment zone, soil fracturing and steam injection for treatment of semivolatile contaminants in low-permeability zones, phytoremediation and mining technologies for removing lead contamination from soil, in situ cooxidation technologies for treating trichloroethylene and jet fuel, radio frequency heating for improving removal of semivolatile compounds, surfactant injection for treatment of NAPLs, and single-phase microemulsion treatment for removal of NAPLs. Also funded in this first round of AATDF projects are an investigation of a laser fluorescence cone penetrometer method for site characterization, development of technical practices manuals for successfully demonstrated technologies, and development of an experimental controlled release site where technologies can be tested following controlled releases of contaminants. The 12 projects are due to be completed by the end of 1997.

in complex geologic settings is difficult to assess because of the difficulty of obtaining representative data. Detailed laboratory, pilot, and field tests are fundamental to proving either efficacy or applicability of new technologies designed to restore these types of sites. A critical question in the development of technologies for this category is how easily data may be extrapolated from one stage of testing to the next due to the difficulty of obtaining data and the inherent variability of the data. For example, determining what size of pilot test area is necessary to adequately represent the full site may be difficult. As shown in Table 5-5, multiple pilot tests may be necessary. A problem in determining either the efficacy or the applicability of technologies for sites in this category is that success at one

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

FIGURE 5-3 Treatability of contaminated sites and level of site-specific testing of remediation technologies required as a function of contaminant and geologic properties. Note that ''H" indicates high and "L" indicates low volatility, reactivity, or solubility. (See Table 5-4 for a listing of sample contaminant compounds in each category.)

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

TABLE 5-4 Classes of Compounds Shown in Figure 5-3

Contaminant Class (as shown in Figure 5-3)

Volatility, Reactivity, and Solubility

Example Contaminants

A

HHL

Hydrocarbon fuels; benzene, toluene, ethylbenzene, and xylene

B

HLL

Trichloroethane, trichloroethylene, tetrachlorethylene

C

HHH

Acetone

D

LHH

Phenols, glycols

E

HLH

Methyl tertiary-butyl ether, tertiary butyl alcohol, methylene chloride

F

LHL

Naphthalene, small polycyclic aromatic hydrocarbons (PAHs), phthalates

G

LLH

Inorganic mixtures, metals of different chemistries

H

LLL

Polychlorinated biphenyls, pesticides, large PAHs

NOTES:

Volatility: High (H) > approximately 10 mm Hg; Low (L) 8 approximately 1 mm Hg

Reactivity: High - biodegradable, oxidizable; Low - recalcitrant

Solubility: High > approximately 10,000 mg/liter; Low 8 approximately 1,000 mg/liter

stage of testing does not assure success at a subsequent stage, and scaleup of the technology may be difficult.

While contaminant and hydrogeologic properties exert the primary influence on the amount of site-specific testing required prior to application of an innovative remediation technology, characteristics of the technology also influence the amount and detail of site-specific data that will need to be collected prior to installation of the technology. When technologies must be brought to the contaminant, more detailed site-specific data will be required than when the contaminant can be brought to the technology. In the first case, taking the technology to the contaminant, the subsurface properties must be detailed on a much finer scale than for the latter case, bringing the contaminant to the technology. Also, the site will need to be monitored much more intensively to prove that remediation is occurring. An example of this situation is use of a reactive treatment technology, such as bioremediation, for which the technology (bioremediation) is brought to the contaminants. To determine whether bioremediation is successful for a complex distribution of contaminants requires intensive monitoring and analysis. The presence of indigenous microbes and their biodegradation potential, the bioavailability of compounds, and the distribution of nutrients and moisture must be understood. Moreover, substances such as nutrients and electron acceptors must be delivered to the zones of contamination to support remediation, which might re-

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

TABLE 5-5 Site-Specific Testing Needs for Remediation Technologies

Category of Site

Data Needed to Determine Efficacy

Data Needed to Determine Applicability

Data Transferability

Commercialization Basis

Ease of Scaleup

Focus of Testing

Highly treatable (category I)

Fundamental properties of technology and site

Fundamental properties of technology and site

High for C-Ca, G-G, SU (for other sites in highly treatable category)

Fundamental properties and case histories

High

Testing for design

Moderately difficult to treat (category II)

Fundamental properties of technology and site

Field test data

Good for C-C, SU (for other sites in moderately treatable category)

Verified data and case histories

Moderate

Testing for application and design

Difficult to treat (category III)

Laboratory, bench, and pilot test data

Laboratory, bench, and pilot test data

Poor; requires site-specific testing

Verified data and site-specific testing

Moderate

Testing for efficacy, application, process verification, and design

Extremely difficult to treat (category IV)

Laboratory, bench, and pilot test data

Laboratory, bench, and pilot test data (several pilot tests)

Poor; requires site-specific testing

Site-specific testing

Poor

Testing for efficacy, application, process verification, and design

a C-C denotes contaminant-to-contaminant transfer of the technology; G-G denotes transfer of the technology from one type of site geology to another (within the same general category of treatability); SU denotes ease of data transfer in scaleup.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

quire manipulating the flow field in a specific way to reach the contaminants. Determining whether any other processes, such as volatilization or mixing with natural waters, is acting to reduce concentrations will also be necessary. On the other hand, when contaminants can be brought to the technology, such as with reactive barriers, the amount of information needed and the application and analysis of the technology are, in relative terms, easier. In the case of reactive barriers, the flow field will need to be manipulated to deliver the contaminants to the barrier, but the manipulation will be on a much larger scale, which is inherently easier to do. Bringing the contaminants to the barrier generally requires less detailed site investigation because the focus is on flow field manipulations rather than on small-scale processes. In addition, technology assessment is much easier, requiring only a comparison of the concentrations of contaminants entering the barrier with the concentrations exiting the barrier, because the processes occurring in the barrier are known. Thus, approaches that bring the contaminants to the technology have an advantage in both the amount and type of data needed for site-to-site transfer and in the amount and type of data needed for evaluating the technology.

TECHNOLOGY PERFORMANCE VERIFICATION

The wide variation in methods used to assess the performance of innovative remediation technologies has made it very difficult for potential clients to judge the validity of remediation technology performance data. The "not tested in my backyard syndrome," in which owners of contaminated sites and regulatory personnel are reluctant to accept technology performance data from another site, is a significant problem in the remediation industry. In part, this reluctance stems from clients' concerns about potential regulatory or legal challenges to the selected remedy. Clients may fear that if they choose an innovative technology and their cleanup remedy is later legally challenged, proving in a court of law that the innovative remedy was, in fact, an adequate selection may be difficult. In deciding whether to admit scientific data into legal proceedings, courts of law must consider factors such as whether standards exist for the collection of such data, whether the data have received widespread acceptance in the scientific community, whether the data have been peer reviewed, and the potential for error in the data.1 Meeting such legal standards may be difficult when innovative remediation technologies are chosen. Thus, a remediation technology developer may invest a great deal in a single field test hoping it will lead to additional customers, but a successful test often fails to lead to client acceptance of the technology, in part because of legal concerns.

1  

A recent Supreme Court case involving a toxic tort claim that Benedectin caused birth defects outlines the newest standards for the admissibility of scientific evidence in courts of law. See Daubert v. Merrell Dow Pharmaceuticals, Inc., 113 S.Ct. 2786 (1993).

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

The fact that lack of credible performance data limits selection of innovative remediation technologies is now well recognized. Several efforts to develop protocols to standardize the testing, data collection, and regulatory approval process for remediation technologies are under way. Box 5-12 summarizes current programs in three categories: those for standardizing data reporting procedures, those for creating a more uniform regulatory approval process, and those for verifying technology performance. In the first category is the Federal Remediation Technologies Roundtable guide that federal agencies are to use in documenting cost and performance of remediation technologies. In the second category are programs by the western states, southern states, a six-state consortium, and Massachusetts to increase the level of regulator confidence in data on innovative remediation technology performance. In the third category are the SITE program (the oldest program for remediation technology verification) and the California Environmental Protection Agency Technology Certification Program.

Although the programs listed in Box 5-12 offer opportunities to report remediation technology performance data, independently verify these data, and specify steps necessary for regulatory approval of innovative remediation technologies, the existence of such a wide variety of programs in itself creates confusion for remediation technology developers and purchasers. Limited efforts to standardize the format for reporting cost and performance data under these various programs are under way, but nevertheless the different programs have different procedures for participation. Thus, the existence of these programs can exacerbate the problems faced by technology vendors in deciding which types of performance data to collect. Furthermore, the programs are voluntary and are not always accepted by agencies other than the ones participating in the program. Having a technology included in one of these programs may not provide a sales advantage except in the limited universe of sites under the jurisdiction of the agencies involved in the program. The costs of collecting all the data necessary for participation can be high, and technology developers may have to disclose company "secrets" in the process. Without the promise of a large market to make up for these costs, it is likely that very few companies will participate in the programs, except perhaps California's, which has a relatively large, well-defined market.

A uniform, widely used national program for testing and verifying the performance of new subsurface cleanup technologies is needed to provide a clear path for technology vendors to follow in planning how to prepare their technologies for the marketplace. The program should focus on verification of technology performance, meaning proving performance under specific conditions and providing assurance of data quality, rather than on certification, meaning guaranteeing technology performance. Because of the wide variation in contaminated sites, no technology can be guaranteed to achieve a given performance level at every site, and some degree of site-specific testing will always be required. However, having a uniform national protocol for reporting performance data and a mecha-

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

BOX 5-12 Testing, Verification, and Regulatory Approval Programs for Remediation Technologies

Data Collection and Reporting Protocols

  • Federal Remediation Technologies Roundtable Guide to Documenting Cost and Performance for Remediation Projects: The Federal Remediation Technologies Roundtable, a consortium of federal agencies involved in cleaning up hazardous waste sites, in 1995 published a guide specifying standard formats for documenting the performance of site cleanup technologies (Federal Remediation Technologies Roundtable, 1995). Agencies are required to use the guide to prepare cost and performance reports for Superfund sites on federal lands (Luftig, 1996). For information, contact the EPA's Technology Innovation Office, (703) 308-9910.

Regulatory Approval Protocols

  • Interstate Technology and Regulatory Cooperation (ITRC) Working Group: The ITRC, a group initiated by the Western Governors Association, is developing regulatory approval protocols for several classes of hazardous waste remediation technologies. Most of the 27 states participating in the ITRC work group have agreed to accept remediation technology test results from other states if the tests are conducted according to the protocols the ITRC is developing. For information, contact the Western Governors Association, (303) 623-9378, or the ITRC's World Wide Web site, http://www.gnet.org/gnet/gov/interstate/itrcindex.htm.

  • Southern States Energy Board Interstate Regulatory Cooperation Project for Environmental Technologies: The Southern States Energy Board is working to develop compatible regulations for environmental technologies in southern states. The project began with a pilot demonstration of data management and integration technologies in South Carolina and Georgia. For information, contact the Southern States Energy Board, (770) 242-7712.

  • Six-State Partnership for Environmental Technology: Six states (California, Illinois, Massachusetts, New Jersey, New York, and Pennsylvania) in 1995 signed a memorandum to develop a process for the reciprocal evaluation, acceptance, and approval of environmental technologies. The partnership has begun this effort with pilot projects to review 12 different environmental technologies, including several for use in contaminated site remediation. For information, contact the New Jersey Office of Innovative Technology and Market Development at (609) 984-5418.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×
  • Massachusetts Strategic Envirotechnology Partnership (STEP): STEP is a recently initiated program to promote use of new environmental and energy-efficient technologies in Massachusetts. Under the program, the state provides opportunities to pilot test technologies on state properties or at state facilities. The STEP program also helps expedite regulatory review and permitting of new environmental technologies using a team of innovative technology coordinators. In addition, it provides all technology developers in the program with a business plan review, including assistance in identifying potential markets and sources of funding. For information, call the Massachusetts Office of Business Development, (617) 727-3206.

Technology Performance Verification Protocols

  • Superfund Innovative Technology Evaluation (SITE) Program: The first program for testing the performance of ground water and soil cleanup technologies, SITE was established in 1986 in response to a congressional mandate in the Superfund Reauthorization Act and Amendments (SARA) of 1986. SARA called for an "alternative or innovative treatment technology research and demonstration program." SITE is run by the EPA's National Risk Management Research Laboratory in Cincinnati. Under the program, EPA funds a select number of technology demonstrations each year. Technology developers can apply to have their technology tested under the SITE program by responding to an annual request for proposals. Developers pay for technology installation and operation costs; EPA pays for data collection and analysis. The SITE program, which has been criticized for failing to provide a market advantage to technologies that pass through it, received no funding in 1996, but funding was reinstated at $6 million in 1997. For information, contact the SITE program, (513) 569-7697.

  • California Environmental Protection Agency (CalEPA) Technology Certification Program: In 1994, CalEPA established an environmental technology certification program in response to a mandate from the state legislature, specified in Assembly Bill 2060. The program will eventually provide mechanisms to certify all types of environmental technologies used in the state. The state's goal is to streamline the regulatory acceptance process for new environmental technologies and to increase customer confidence in performance data. The program began with a series of pilot tests to certify performance of a range of pollution prevention and environmental monitoring technologies. For information, contact CalEPA's Department of Toxic Substances Control, Office of Pollution Prevention and Technology Development, (916) 324-3823.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

nism for reviewing the validity of the data would increase client and regulatory acceptance of credible performance data and would enable credible defense of the choice of an innovative remedy in courts of law. It would also facilitate the extrapolation of data from one site to another. The SITE Program, the only national program available for verifying remediation technology performance, has inadequate breadth, funding, and recognition to provide the needed level of remediation technology performance validation.

Verification of remediation technology performance should require reporting of data in the two categories described earlier in this chapter: (1) data showing that the technology works in reducing risks posed by specific contaminants under specific site conditions and (2) data linking the observed risk reduction with the technology. At least two types of evidence should be provided for each of these categories. The application for verification should provide a data summary sheet similar to the reports shown in Boxes 5-2, 5-3, 5-4, and 5–5. It should also specify the range of contaminant types and hydrogeologic conditions for which the technology is appropriate, and separate performance data should be provided for each different type of condition. Performance data should be entered in the coordinated remediation technologies data bases recommended in Chapter 3.

Three possible types of organizations could serve as the center of the verification program:

  • EPA: The EPA SITE Program could be greatly expanded to allow for verification of a wide range of remediation technologies. Verification could be provided by EPA staff or contractors at EPA laboratories.

  • Third-party franchise: A third-party center (under the direction of a private testing organization or professional association) could work with technology developers to establish test plans and conduct tests in the field or at a test facility, as appropriate. Staff of the center would evaluate the results and submit a verification report to the EPA.

  • Nonprofit research institute: A nonprofit research institute affiliated with a university could establish technology evaluation protocols, either independently or based on guidelines from the EPA and other agencies. It could franchise other laboratories to assist with the testing and to evaluate results. These laboratories would then submit results to the institute for verification.

Regardless of which type of entity is responsible for verification, establishing a credible, widely used testing process will be essential. Questions regarding data acquisition, quality assurance and control, and appropriate measures of success would all need to be addressed. Whether data provided by the technology developer would be allowed in the verification process, or whether the data would need to be generated by an independent organization, would need to be established. The relative value of retrospectively and prospectively acquired data would need to be established. Roles of stakeholders (see Chapter 4) in the verification

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
×

process would need to be defined. Incentives would need to be developed to participate in and use data produced by the program.

The verification program should be launched with a series of small pilot projects involving a variety of technology types, environmental media, and technology developers. The pilot programs would assist in checking whether the test protocols are adequate and in determining quality assurance and control procedures. In the pilot programs, technology vendors would draft a technology test plan in conjunction with the verification entity, which would either test the technology directly or oversee tests conducted by others. Verification of the results (or a decision not to verify the results) by the verification entity would follow.

DATA SHARING THROUGH GOVERNMENT AND INDUSTRY PARTNERSHIPS

Private industries and government agencies "own" similar subsurface contamination problems. Yet, as discussed in this chapter, companies and agencies can be reluctant to accept remediation technology performance data generated by another company or agency. In addition to encouraging data acceptance through a verification program, sharing of data could be encouraged by forming technology testing and development partnerships including government agencies and a number of private companies. Such partnerships would, in the long run, provide cost savings to participating companies and agencies because they would leverage technology testing costs across a group of organizations so that no one organization would bear the entire cost.

One such partnership, the Remediation Technologies Development Forum (RTDF) already exists. The RTDF is an EPA-facilitated umbrella organization established in 1992. Through the RTDF, government and industry problem "owners" meet periodically to share information about problems of mutual concern and work together to find solutions (EPA, 1996b). The RTDF is currently supporting $20 million in work effort. Several formal RTDF teams are in place to develop innovative remediation technologies, and the RTDF is considering establishing more such teams (Kratch, 1997).

The first RTDF team formed is known as the Lasagna Consortium(TM). Through this partnership, Monsanto, DuPont, General Electric, the EPA, and the Department of Energy (DOE) are cooperating to develop a process that uses electroosmosis (see Box 3-3 in Chapter 3) to move contaminated ground water from low-permeability formations to in situ treatment zones. The EPA is supplying research capabilities, and the DOE is supplying funding and a test site at its Paducah, Kentucky, facility. The industrial partners are supplying program management, basic laboratory development, and design and construction capabilities. A successful pilot test to prove the principles underlying the technology's performance was completed in 1996, and a much-refined scaleup using zero-valent iron

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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reaction zones (see Chapter 3 and Box 5-6) to destroy trichloroethylene is in progress.

A second RTDF team is investigating bioremediation of chlorinated solvents. The team consists of a consortium of six companies (DuPont, General Electric, Monsanto, Dow Chemical, ICI Zeneca, and Beak Consultants) working in partnership with the EPA, DOE, and Air Force. The consortium is investigating three different types of bioremediation: accelerated dechlorination, cometabolic bioventing, and intrinsic bioremediation. The DOE and Chlorine Chemical Council are providing funding, and the Air Force is providing test sites at the Dover, Delaware, Air Force Base. EPA is providing research in bioventing. The industrial partners are providing program management, laboratory studies, and design of the accelerated and intrinsic bioremediation protocols. Two pilot tests are under way, and work is being completed to select additional sites for a parallel series of pilot tests.

Recently established RTDF teams are demonstrating passive-reactive barriers for treatment of chlorinated solvents, in situ technologies for treating metals, and in situ techniques for cleaning up contaminated sediment. The RTDF is also establishing additional teams to investigate surfactant flushing systems for the treatment of DNAPLs in ground water and phytoremediation for the treatment of organic contaminants in soils.

The major driver behind the RTDF consortia is the desire to develop sound technologies that will reduce remediation costs to government and industry users. The close collaboration of those involved is leading to a shared understanding of the technologies. Participants hope that the effort will lead to early acceptance and application of the technologies, because three of the major stakeholders (technology users, developers, and regulators) are a party to the process. The EPA's participation has helped remove regulatory barriers to pilot testing.

It is too early to determine whether the RTDF arrangement will lead to rapid commercialization of the technologies being tested under the program. However, many elements are in place to speed the technologies through the pilot testing phase. For example, if the lasagna process proves successful, it is scheduled for full-scale implementation at Paducah, meaning there is a guaranteed first client for the technology. While such industry and government partnerships may not solve all the problems associated with testing and commercialization of remediation technologies, they should be encouraged as a potentially effective means for involving major stakeholders in mustering national resources to find solutions.

CONCLUSIONS

The wide variation in protocols used to assess the performance of innovative technologies for ground water and soil remediation has interfered with comparisons of different technologies and evaluation of performance data. In part because of the lack of standard performance reporting procedures, owners of con-

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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taminated sites and environmental regulators may hesitate to consider data from other sites in assessing whether an innovative remediation technology may be appropriate for their site. While a technology developer may invest large sums in conducting a field test to prove technology performance, potential clients may be hesitant to accept data from the field test if it was not carried out on the client's site and under the client's supervision.

The problem of variability in remediation technology performance data is now well recognized by environmental regulators, and various federal and state agencies have made efforts to standardize data collection and reporting procedures. However, the efforts of these agencies have not been coordinated. They thus provide little assurance to technology developers that following the procedures will provide a net benefit to the developer. The developer may expend large sums on testing a technology according to one agency's procedures, only to learn that the procedures will not be accepted by another agency. Some degree of national standardization in processes used to evaluate the performance of innovative remediation technologies is needed to allow for greater sharing of information, so that experiences gained in remediation at one site can be applied at other sites. In addition, more opportunities need to be created for cooperative technology development partnerships including government, industry, academia, and other interested stakeholders to encourage sharing and acceptance of data.

Recommendations

To standardize performance testing protocols and improve the transferability of performance data for innovative remediation technologies, the committee recommends the following:

  • In proving performance of an innovative remediation technology, technology developers should provide data from field tests to answer the following two questions:

  1. Does the technology reduce risks posed by the soil or ground water contamination?

  2. How does the technology work in reducing these risks? That is, what is the evidence proving that the technology was the cause of the observed risk reduction?

To answer the first question, the developer should provide two or more types of data leading to the conclusion that contaminant mass and concentration, or contaminant toxicity, or contaminant mobility decrease following application of the technology. To answer the second question, the developer should provide two or more types of evidence showing that the physical, chemical, or biological characteristics of the contaminated site change in ways that are consistent with the pro-

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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cesses initiated by the technology, using evaluation procedures such as those shown in Table 5-1.

  • In deciding how much site-specific testing to require before approving an innovative remediation technology, clients and environmental regulators should divide sites into the four categories shown in Figure 5-3: (I) highly treatable, (II) moderately difficult to treat, (III) difficult to treat, and (IV) extremely difficult to treat. For category I sites, site-specific testing of innovative remediation technologies should be required only to develop design specifications; efficacy can be determined without testing based on a review of fundamental principles of the remediation process, properties of the contaminant and site, and prior experience with the technology. For category II sites, field pilot testing should be required to identify conditions that may limit the applicability of the technology to the site; testing requirements can be decreased as the data base of prior applications of the technology increases. For category III sites, laboratory and pilot tests will be necessary to prove efficacy and applicability of the technology at the specific site. For category IV sites, laboratory tests and pilot tests will be needed, and multiple pilot tests may be necessary to prove that the technology can perform under the full range of site conditions.

  • All tests of innovative remediation technology performance should include one or more experimental controls. Controls such as those summarized in Table 5-2 are essential for establishing that observed changes in the zone targeted for remediation are due to the implemented technology. Failure to include appropriate controls in the remediation technology performance testing protocol can lead to failure of the test to prove performance.

  • The EPA should establish a coordinated national program for testing and verifying the performance of new remediation technologies. The program should be administered by the EPA and implemented by either EPA laboratories, a private testing organization, a professional association, or a nonprofit research institute. It should receive adequate funding to include the full range of ground water and soil remediation technologies and to test a wide variety of technologies each year. A successful test under the program should result in a guaranteed contract to use the technology at a federally owned contaminated site if the technology is cost competitive. The program should be coordinated with state agencies so that a technology verified under the program does not require additional state approvals.

  • Applications for remediation technology verification under the new verification program should include a summary sheet in standard format. The summary sheet should contain information similar to that presented in Boxes 5-2, 5-3, 5-4, and 5-5. It should include a description of the site at which the technology was tested, the evaluation methods used to prove technology performance, and the results of these tests. It should also include a table showing the types of data used to answer each of the two questions needed to prove technology performance.

Suggested Citation:"5 TESTING REMEDIATION TECHNOLOGIES." National Research Council. 1997. Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization. Washington, DC: The National Academies Press. doi: 10.17226/5781.
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  • Applications for remediation technology verification should specify the range of contaminant types and hydrogeologic conditions for which the technology is appropriate. Separate performance data should be provided for each different major class of contaminant and hydrogeologic setting for which performance verification is being sought.

  • Data gathered from technology performance tests under the verification program should be entered in the coordinated national remediation technologies data bases recommended in Chapter 3. Data should be included for technologies that were successfully verified and for those that failed the verification process.

  • Technology development partnerships involving government, industry, academia, and other interested stakeholders should be encouraged. Such partnerships can leverage resources to speed innovative technologies through the pilot testing phase to commercial application.

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Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization Get This Book
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Most books on ground water and soil cleanup address only the technologies themselves—not why new technologies are or are not developed. Innovations in Ground Water and Soil Cleanup takes a holistic approach to the entire field, addressing both the sluggish commercial development of ground water and soil cleanup technologies and the attributes of specific technologies. It warns that, despite cleanup expenditures of nearly $10 billion a year, the technologies remain rudimentary.

This engaging book focuses on the failure of regulatory policy to link cleanup with the financial interests of the company responsible for the contamination. The committee explores why the market for remediation technology is uniquely lacking in economic drivers and why demand for innovation has been so much weaker than predicted.

The volume explores how to evaluate the performance of cleanup technologies from the points of view of the public, regulators, cleanup entrepreneurs, and other stakeholders. The committee discusses approaches to standardizing performance testing, so that choosing a technology for a given site can be more timely and less contentious. Following up on Alternatives for Ground Water Cleanup (NRC, 1994), this sequel presents the state of the art in the cleanup of various types of ground water and soil contaminants. Strategies for making valid cost comparisons also are reviewed.

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