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The Alternative Cover Assessment Project Workshop was held on September
24 and September 25, 1997, at the Cincinnati Bell Long Distance Center in
Cincinnati, Ohio. The workshop included presentations, discussions, and
work sessions. Steve Rock of the U.S. Environmental Protection Agency,
Office of Research and Development, National Risk Management Research
Laboratory (EPA NRMRL) facilitated the workshop, along with Tom Wong of
Union Carbide and David Carson of EPA NRMRL. Workshop attendees are listed
in Attachment A.
INTRODUCTION AND WELCOME
Steve Rock, EPA
NRMRL
Steve Rock welcomed the participants and reviewed the workshop's
purpose, process, and agenda. He stated that there is a need to address
whether alternative covers can be used in widespread applications across
the country. Communication gaps exist between people who have information
and those who need information on alternative covers. Substantial
information gaps also exist. The workshop is intended to help identify
these information gaps and ways to address them. Rock stated that he hoped
the workshop would provide the opportunity to create innovation and to
develop alternative covers that are intuitive and easy to understand.
RTDF OVERVIEW
Phil Sayre, EPA Technology
Innovation Office
Phil Sayre of EPA's Technology Innovation Office (TIO) provided participants with background information on the Remediation Technologies Development Forum (RTDF). He explained that EPA established the RTDF in 1992 to identify ways that the Agency and industry can work together to solve the nation's hazardous waste remediation problems. The goal of the RTDF is to move from laboratory to field testing to prove new innovative technologies for hazardous waste cleanup. RTDF establishes self-managed action teams with membership from industry, research centers and institutes, universities, and Federal agencies such as EPA, the Department of Energy (DOE), and the Department of Defense (DOD). Under the RTDF, EPA/ORD provides "validation" of new technologies, as well as technical support and field testing. TIO provides meeting support and other services.
Sayre stated that there are seven RTDF action teams, of which the Phytoremediation of Organics team is the newest. This team has three subgroups, one focused on vegetative caps (the workshop sponsor), one on degradation of TCE in near-surface ground water, and another on degradation of petroleum wastes in near-surface soils.
Sayre described the Bioremediation of Chlorinated Solvents Consortium,
which is the most evolved of the RTDF action teams. This consortium is
bound together by a research agreement. Companies participate on a "pay-to-play"
basis and benefit from patent rights and access to the technologies that
are developed. The consortium includes a steering committee and separate
action teams.
WORK SESSION 1--TECHNOLOGY INTRODUCTIONS AND
DEFINITIONS
RCRA CAPS: DESIGN AND LONG-TERM PERFORMANCE ISSUES
David Carson, EPA NRMRL
David Carson provided workshop participants with a primer on RCRA caps and containment covers. His presentation included the following key points:
A participant asked if EPA plans to clarify the hydraulic conductivity regulatory requirement. He suggested that a flux-type definition might be more appropriate. Felix Flechas, EPA Region 8, responded that EPA has not been asked to look at this requirement.
Another participant asked what EPA means by "long-term performance." Carson responded that it means the ability to isolate waste for as long as risk from potential failure is present.
One individual asked if EPA is working on active waste containment systems. Carson responded that NRMRL began to look into these systems--also known as bioreactor landfills--several years ago but these efforts have slowed over the past two years because of resource limitations.
Another participant asked about frost protection and the long-term
service life of geosynthetic materials. Carson responded that we do not
know for sure how long these materials will last. By applying modeling
systems for other environmental uses of polymers to geomembranes, EPA has
determined a service life for geomembranes of 800 to 900 years, under
worst-case conditions. Freezing and thawing cycles are a concern. The
prudent approach is to stay out of the frost-permeable zone. Some research
shows that freezing and thawing cycles have nominal effects on GCLs and
geomembranes.
THE VEGETATIVE CAP
Tom Wong, Union Carbide
Tom Wong provided participants with an introduction to vegetative caps. He made the following key points:
Felix Flechas commented that 5 to 10 years of high maintenance may be necessary for vegetative covers in high altitude or semi-arid climates. Flechas also asked Wong to clarify if harvest is necessary with a vegetative cap. Wong responded that harvest is necessary when the targeted waste includes metals. For organics, harvest may be unnecessary, but the question remains open for further investigation.
One participant asked how erosion is controlled in vegetative caps. Wong responded that erosion becomes a concern with a vegetative cap only in situations where it is so severe that it enters the waste itself; otherwise, erosion is allowed to occur and then repair itself.
Another participant asked if coniferous tree species can be used for vegetative caps. Wong responded that deciduous species have been used in most places, but coniferous species may be valuable alternatives because they evapotranspire throughout the year.
Wong concluded his presentation by summarizing key aspects of the "living cap" concept:
WORK SESSION 2--PRESENTATIONS: CASE HISTORIES
AND APPLICATIONS
EVALUATING VEGETATIVE AND OTHER NON-CONVENTIONAL COVERS
Steve Dwyer, Sandia National Laboratories
Steve Dwyer of Sandia National Laboratories, Albuquerque, New Mexico, discussed a study that compares four alternative covers to two baseline covers. Sandia Labs undertook the project following an endorsement by the Western Governor's Association. The Association recognized a need throughout the southwest for effective, arid-environment alternatives to baseline covers. In the study's initial phase, specifications were developed for the six covers and each was competitively bid.
Each of the six covers is 300 feet long, 40 feet wide, and instrumented for water balance. Dwyer described each of the six covers:
Two baseline covers:
Four alternative covers:
Dwyer also described a side study that is comparing 24 different surface treatments in 24 test plots. The purpose of the side study is to determine the quickest and least expensive ways to establish vegetation.
Dwyer stated that rainfall in New Mexico has been very high this year because of the El Niño effect. Moisture has come through all of the covers. The capillary barrier and soil monolithic covers have dried very quickly. Craig Benson commented that his work has shown that bentonite-amended covers heal very quickly. One participant asked why water is coming through the GCL. Dwyer hypothesized that one of the seams might have been slightly opened during construction. Greg Richardson commented that it is not surprising to see some initial leakage through a GCL while hydrating.
One individual asked if cracking was reduced in liners that were installed dry-of-optimum. Dwyer responded that there was less cracking in liners that were installed dry-of-optimum in the climate of the test project.
A second participant asked if native species were used for revegetation. Dwyer responded that only native species were used--predominantly grasses, but also some shrubs. Botanists from the University of New Mexico developed a mixture of native species appropriate for the site.
Another attendee asked what factors should be considered when installing under wet-of-optimum conditions in arid areas. Dwyer responded that he is not an advocate of wet-of-optimum installation and that he knows of no way to stop desiccation cracking.
A participant then asked if initial findings from the study were available. Dwyer responded that the data cannot be released at this time because DOE will not receive it until September 30, 1997. DOE plans to release the study findings annually for 5 years. Dwyer suggested that participants contact him in October for information about how to receive the first-year data.
Another participant asked how it was determined that 30 inches was adequate for a sponge layer. Dwyer responded that he used software packages such as HELP (Hydrological Evaluation of Landfill Performance) and soil monitoring data taken from nearby environmental restoration sites, The data show that there is little moisture movement below the 30-inch level.
An individual asked if there is contamination on the site. Dwyer stated that the site is clean.
A participant asked how leakage is monitored in the study. Dwyer stated
that Time Domain Reflectometry (TDR) probes were installed underneath the
liners to monitor for leakage. Another participant asked how runoff from
the covers is monitored. Dwyer responded that gutter systems have been
installed that route runoff to a collection system.
TREATMENT UNIT CAPPING WITH VEGETATION
Lucinda
Jackson, Chevron Corporation
Lucinda Jackson, an ecologist with Chevron Corporation, discussed four Chevron sites: two vegetative cap field tests, one site where a vegetative cap has received regulatory approval, and one site where the treatment has yet to be determined. She stated that Chevron is interested in using vegetative caps at sites such as refineries, tank farms, marketing terminals, land farms, and Superfund sites. At each of these sites, Chevron's goal is decontamination and the prevention of leaching.
She provided a brief description of each project:
Jackson also discussed a study in which Chevron has examined uptake of five metals in different grass and broadleaf species. The study found that alyssum can take up lead, and that cabbages, turnips, and alyssum can take up chromium, copper, and cadmium. No plants were found to take up mercury.
Jackson stated that vegetative caps provide greater net environmental benefits than traditional remediation methods. Chevron hopes that the concept of net environmental benefit will gain acceptance by regulators. She discussed Chevron's efforts to remediate a site using pickerelweed, which provides habitat for the endangered salt marsh harvest mouse.
A participant asked how leaching was being measured at the sites. Jackson stated that ground-water monitoring wells are used to monitor leaching.
Another participant asked if Chevron envisions a plan for controlling
uptake and the ultimate fate of vegetation growing on these sites. Jackson
responded that vegetative caps on sites with high levels of metals are a
concern. They require harvesting and may constitute an "attractive
nuisance" because they provide habitat for animals that may be at
risk from exposure to metals. She stated that she is comfortable using
vegetative caps for sites containing petroleum hydrocarbons, since plants
do not take up hydrocarbons. Jody Waugh of R. F. Weston, Inc., commented
that the solution is often worse than the problem, and he wondered why the
ecological consequences of remediation are not included in the risk
assessment.
CAPPING WITH TREES
Louis Licht, Ecolotree,
Inc.
Louis Licht of Ecolotree, Inc. discussed his work using trees to cap sites.
At his first study site, located in Iowa, Licht used poplar trees as a watershed buffer to abate agricultural nonpoint pollution. In his study, Licht planted 5½ foot poplar stems in trenches 5 feet deep to determine if roots could be established at depths of 5 feet. After 16 months, the trenches were filled with roots. Within 6 years, measurements showed a five-fold increase in soil microbes. Licht stated that the mature rows of poplars acted as miniature sedimentation dikes. The poplar buffer substantially reduced sediment and nitrogen entering the stream. In non-arid climates such as Iowa, poplars at full canopy can discharge 10,000 gallons of water per acre per day. Licht explained that he selected poplars for the study because they are an "industrial" species that can be easily managed genetically. Also, poplar is a phreatophytic species that can thrive with its root system submerged.
Licht described several project sites where he has used poplar trees to cap landfills:
Licht commented that for phyto-capped landfills to succeed, the owner must be committed to the approach and willing to perform the necessary maintenance.
Licht stated that regulatory requirements (e.g., the 10-5 centimeter per second requirement contained in RCRA Subtitle D) can hobble the economics of using trees and discourage owners from pursuing phyto approaches.
A participant asked if the trees on these sites were causing hydraulic
lift. Licht responded that this may be the case, depending on the site's
osmotic conditions. Another participant asked if Licht was measuring
transpiration. He stated that he is not putting transpirometers on leaves
but is assessing transpiration using TDR.
A PROPOSED EVAPOTRANSPIRATION COVER ON A SUPERFUND SITE
Felix Flechas, EPA Region 8
Felix Flechas from EPA Region 8 discussed the regulatory issues associated with an evapotranspiration (ET) cover proposed for a 40-acre site at F. E. Warren Air Force Base in Cheyenne, Wyoming. The landfill, which contains hazardous waste, operated for 15 years and received waste from the base.
Before he began his presentation, Flechas read a statement clarifying the Agency's position on the proposal:
The Denver Office of the EPA was recently asked to consider this conceptual design for an ET cover on this landfill at F. E. Warren Air Force Base. Many claims have been made regarding Region 8's supposed acceptance of this proposal. We wish to clarify for the record that EPA has not accepted nor seen a final design of the proposed cover. The cover design is only conceptual and the concept has only been accepted as a demonstration of ET covers. The Region has stated that the cover can only be installed as a demonstration with an extensive performance monitoring system. Any representation to the contrary falsely represents EPA Region 8's position on this cover proposal.
Flechas explained that the original Record of Decision for the site required the installation of a RCRA Subtitle C cover. Subsequently, the Air Force proposed an ET cover concept as an alternative to the RCRA Subtitle C cover. The Air Force proposed to cover the site with 30 inches of loam.
Flechas stated that EPA has learned a number of lessons from regulatory and design issues raised by the project. He also said that his remarks would include a list of things that must be considered when a regulatory agency is approached with an alternative cover design--in this case, an evapotranspiration cover.
Flechas made the following key points:
Flechas enumerated several lessons learned from the F. E. Warren Air Force Base project:
One participant asked how long monitoring is to continue at the site. Flechas stated that this issue has yet to be resolved. Opinions range from 5 to 30 years.
Another participant asked if EPA Region 8 had determined an acceptable thickness for the soil cover. Flechas responded that EPA would have been likely to require an additional 24 inches of material in order to achieve a total thickness of 5 to 5½ feet. (In this region of Wyoming, the frost-permeable layer is 5 to 5½ feet.)
An attendee asked what the consequences would be if the proposed
approach is shown to fail. Flechas responded that an evaluation will take
place if monitoring indicates that leakage is greater than expected. One
participant stated that, from a risk standpoint, the consequences of
exceeding the hydraulic performance standard vary depending on the
conditions of the site.
A REVEGETATIVE CAP ON A SLUDGE LAGOON
John
Fletcher, University of Oklahoma
John Fletcher of the University of Oklahoma described a study of a 1-acre site in Texas, which he is undertaking in conjunction with Union Carbide. The study has found that plants are contributing to the disappearance and degradation of contaminants on the site.
Fletcher stated that the site, which is surrounded by an earthen berm, is located in the middle of an industrial complex. When the site was in use, trucks deposited waste material into a basin on the site. The distribution of contaminants on the site is very heterogeneous. The site was taken out of use 20 years ago and drained. No cover material was placed on the basin. The site is now covered with voluntary vegetation that was transported naturally to the site by seed and other means from outlying areas. Fifty species of plants are now present, and vegetation on the site is robust. The most prominent plant on the site is mulberry. Other important species include hackberry, Bermuda grass, sunflowers, and verbena.
Throughout the site, PAH levels are lowest within the top foot of soil, increase through descending soil layers, and are highest within the sludge.
Fletcher discussed the contribution that plants are making to the conversion of sludge at the site. He characterized the conversion as a biological event--not just a plant event. Root systems provide binding surfaces that prevent contaminants from leaching. Root systems foster the growth of microbes, and the aeration provided by root systems has had a significant impact on microbial activity at the site. The largest zones of sludge clearing are found beneath the oldest trees on the site. In contrast, sludge is found underneath grasses on the site at comparatively shallow depths of 1½ feet.
Fletcher said that 196 species of PAH-degrading bacteria have been identified at the site. The total microbial population of PAH degraders is highest next to the plant roots. The PAH-degraders are of several genera, some of which have not been well covered in the literature.
The distribution of plant species on the site is not in keeping with the distribution of species off site. For example, mulberry occupies 37 percent of the site but occupies only 5 percent of nearby sites. Fletcher hypothesized that species that predominate on the site have the capacity to tolerate the chemicals and the climate of the basin. He commented that sites such as this one can be tremendously valuable in helping to identify native plants that are well-suited for phytoremediation.
One participant asked if Fletcher had compared the depth of mulberry roots off site to those on site. Fletcher responded that he hoped to compare root depths in future research. He added that mulberry roots generally penetrate to depths of 10 feet, but roots of Osage orange and eastern red cedar can penetrate to depths of 25 feet.
Another participant asked if the distribution of contaminants on site could be explained by leaching. Fletcher responded that 10-fold concentration differences due to leaching are unlikely. He added that, if PAHs were leaching, one would expect to find a band of accumulated contaminants--most likely in the transition zone. However, Fletcher said, there is no plane of accumulated contaminants on the site.
An attendee asked if the study has included any mass balance tests. Fletcher clarified that no experiments are being conducted on the site, only analyses of existing conditions.
Another participant asked about the depth of the water table below the
site. Fletcher responded that the depth varies seasonally. At some times
of the year, the sludge zone is saturated.
GROUP WORK SESSIONS
REGULATORY ISSUES
Steve Rock asked workshop participants to focus on the following question: In order to accept an alternative cap, what does a regulator need to know?
Ross del Rosario, EPA Region 5, began the discussion by describing a site that he is working on near Akron, Ohio. The applicants have proposed to install poplars as an alternative to a RCRA Subtitle C cap. He stated that he is in the process of gathering information from other EPA regions that have had experience with alternative caps. He has found that people are stumped by alternative cover proposals, particularly because they are relying on old performance standards.
Greg Richardson of G. N. Richardson & Associates commented that he would view the use of poplar trees as an ongoing remedial action different from a final closure action. Richardson stated that, if he were a regulator, he would require extensive perimeter monitoring in such cases. With such monitoring requirements, some clients would be likely to select entombment as the cheaper alternative.
John Fletcher stated that dynamic living systems degrade contaminants and thus reduce the risks they pose.
Chris Rhyne, EPA Office of Solid Waste, stated that unless EPA changes its regulations, we will be stuck in RCRA programs with containment as the option of choice. He commented that vegetative caps are unlikely to decontaminate wastes that are 30 to 50 feet deep. In these cases, containment may be the only option.
Lou Licht stated that he selected poplars as an alternative cover species because their performance can be predicted. By using poplars, he can project performance for regulators 5 years into the future. He stated that we need to ask how regulations should be changed so that vegetative alternatives can go forward. He added that it is necessary to move beyond the assumption that regulations cannot be changed.
Glenn Wilson, Desert Research Institute, commented that the group's discussion appeared to be decoupling containment from remediation. He stated that vegetation is a containment tool, just as a GCL is a containment tool.
Lucinda Jackson, Chevron, stated that regulations should consider the degradation of contaminants. Regulators should also recognize the net environmental benefits of vegetative caps, then compare these benefits to those of standard caps. She commented that, if too many expensive restrictions are placed on vegetative caps, people will not pursue these alternatives.
Scott Potter of Geraghty & Miller, Inc. stated that his firm is currently working on two vegetative cover projects--one in EPA Region 3 and the other in EPA Region 5. He commented that it has been difficult to define performance standards to present to the Agency. He also stated that he has been unable to find existing models that adequately address tree cover systems. His firm has developed its own water balance model, which it will present to the Agency. Jeff Smith, also of Geraghty & Miller, stated that it may be more appropriate to be held to a risk-based standard than a hydraulic standard, particularly at a site where natural attenuation occurs.
Tom Wong, Union Carbide, suggested that regulations need to include risk-based analysis. They also need to include an element of reasonableness.
Greg Richardson commented that it is necessary to be aware of the political realities of alternative caps. For the public, these are very emotional issues, not technical ones. He suggested that the public is very unlikely to accept poplar trees as a landfill cap.
Steve Rock asked the workshop participants what specific regulations need to be examined. He asked whether RCRA Subtitle C or RCRA Subtitle D would be easier to work with initially.
Lou Licht commented that a "beachhead" is needed. He asked the workshop participants if they could come to consensus on one situation where they believe that vegetative caps are appropriate.
Bob Shelnutt of EPA Region 9 commented that what the group might
consider appropriate and what the public would consider acceptable are
likely to be two different things altogether. He suggested that the group
begin by considering what might be most easy to "sell" to the
public.
APPROPRIATE SITES
Steve Rock asked workshop participants to consider the following question: If we are not limited by geography or climate, what are the limiting factors for vegetative caps?
Greg Richardson discussed the use of vegetation as a means of removing contaminants from dredge sediments. The U.S. Army Corps of Engineers has studied the use of wetland plants to take up metals from contaminated sediments and has concluded that this approach is a viable means of remediating problematic sediments. Richardson suggested that vegetative alternatives might be most appropriate in areas such as inert landfills, old municipal solid waste landfills, and dredge sediments, where large quantities of waste contain very low concentrations of contaminants. Richardson stated that vegetative caps are not appropriate for "hot spots" that contain, for example, RCRA Subtitle C industrial wastes.
Paul Schroeder, Army Corps of Engineers, stated that remediation must be viewed as distinct from closure. The discussion of using vegetation to remediate wastes and to cap sites "muddies the waters." He stated that ET caps may be appropriate for sites with low concentrations of contaminants.
John Fletcher stated that it is important to remain open-minded about phytoremediation. He urged participants not to underestimate what plants, in combination with microflora, can do. He commented that individuals may find it more acceptable to consider phytoremediation as an "extended open cap" situation rather than as closure.
Jeff Smith stated that, if an ET vegetative cover is implemented as a remediation, at the end, there may be no need for closure. He stated that it may not always be appropriate to apply the hydraulic performance standard when ET covers are used as remediation or in support of remediation.
Mark Ankeny of Daniel B. Stephens & Associates suggested that it might be useful to develop a primer, using projects presented earlier in the workshop, to help people understand the basic concepts of vegetative caps and phytoremediation. He stated that it would be useful to define terms such as "performance criteria" for alternative caps.
Bob Shelnutt stated that it is not necessary to view remediation and containment as "either/or" alternatives. He commented that a better definition of risk is needed.
Fran Kremer of EPA's Bioremediation Program stated that it is necessary to come up with quality field data to assure regulators that what is being presented is in fact true. She agreed with comments that the current rules hinder phytoremediation alternatives; however, without quality data, the rules cannot be changed. She stated that the first step is to gather data, then develop models that utilize these data. Finally, longer-term monitoring systems need to be developed that ensure that human health and the environment are being protected. The last step is to reach agreement on closure requirements.
Felix Flechas commented that both RCRA and Superfund address remediation, and both take a risk-based approach to remediation. RCRA addresses closure, although Superfund does not. RCRA's corrective action regulations have allowances for risk-based decision-making. Closure, however does not allow for risk. Therefore, phytoremediation cannot be viewed in the context of closure, but in the context of a treatment in which the goal is to lower the overall risk.
Steve Rock observed that phytoremediation approaches can combine both remediation and closure. For example, with a vegetative cap, the goal might be to remediate the top 20 feet, which then acts as a cap for the bottom 40 feet. Rock asked how one switches from a closure track back to the remediation track.
Flechas stated that RCRA makes allowances for saying that full remediation is technically impracticable in the short term. Flechas also discussed the concept of "innovative technology," which is included in Superfund but not in RCRA. Under Superfund, regulatory agencies are encouraged to try innovative technologies at federally owned Superfund sites, even though there may be some quantity of risk associated with the technology.
Craig Benson of the University of Wisconsin-Madison commented that frustration occurs when applicants come to the table with a plan for an alternative cover and then "throw the whole thing on the regulatory agency's lap." He suggested that a more successful approach is to build a partnership with the involved regulatory agencies, in which the partners define at the beginning what will be needed in order to demonstrate that the approach is acceptable.
Paula Estornell of EPA's Superfund Office suggested that the workshop participants compile a list of all alternative covers know to them, including demonstration sites, proposed sites, and full-scale field applications. Steve Rock commented that the list could form the basis of a database that would serve as an important resource. The group then brainstormed the following list of fields for the database:
The group agreed to develop a list, including name of site and name of
contact person, before leaving for the day. The site names are listed
below:
| 1. Forensic 2. Sludge Disposal Impoundment 3. Nobel 4. Monticello Utah 5. UMTRA 6. UMTRA Disposal Cells 7. Hill Air Force Base 8. Hanford Barrier 9. Makey Flats, Kentucky 10. Beltsville, Maryland 11. U.S. Ecology 12. Eagle Flat, Texas 13. Nevada Test Site 14. Rocky Mountain Arsenal 15. Industrial Excess Landfill 16. Woodlawn Landfill 17. 110 Sand Site 18. City of Albany 19. Tibbets Road Site 20. Fort Carson, Colorado (Landfills 5 & 6) 21. F.E. Warren Air Force Base |
22. City of Glendale Landfill 23. Greater Wenatzite 24. Artemont, California 25. Grede Foundaries 26. Idaho National Engineering & Environmental Laboratory 27. Sandia National Laboratories 28. Amana, Iowa 29. Lakeside Landfill 30. Bluestim Landfill #1 31. Bluestim Landfill #2 32. Fort Madison 33. Riverbend Landfill 34. Woodburn Wastewater Treatment Plant 35. Oremet Titanium 36. Weyerhaeuser 37. Chambers Landfill 38. Clarence Corporation 39. Union Electric 40. Lexington Landfill |
Brent Nixon of the Air Force Institute of Technology discussed a
database that the Air Force maintains, which includes 600 landfills that
fall into the "forensic" category. His research has shown that
less than half of these landfills have "failed." In making this
determination, he examined ground-water contamination and, where data were
available, surface water and soil contamination in the perimeter. The
results of Nixon's research will be published in the next issue of Waste
Management and Research.
CRADAs, COOPERATIVE STRUCTURES, AND AGREEMENTS
Larry Fradkin of EPA's Office of Science Policy briefed workshop participants on RTDF partnerships and Cooperative Research and Development Agreements (CRADAs). Under a CRADA, EPA can work directly with private industry on joint research and development efforts. EPA can provide technical assistance, equipment, supplies, facilities, and funds; private partners (such as trade associations, universities, individual industries, and industrial consortia) can provide the same. A CRADA frees EPA from many of its restrictions on working with industry. A CRADA can allow EPA to work on proprietary information, and it can exempt proprietary data from Freedom of Information Act requirements for up to 5 years.
Companies can also form research consortia, which provide certain exemptions from anti-trust laws. Consortia are free to set their own ground rules. Agreements can vary in detail and are easy to enter into and get out of. A CRADA is the legal mechanism that holds a consortium together.
Advantages of these arrangements include the sharing of information and expertise and the pooling of resources among players.
Fradkin cautioned that the technology developed by a consortium that includes EPA researchers may not necessarily be accepted by EPA regulators. He suggested bringing the final decision-makers into the process as early as possible to help enhance their understanding and increase the chances that they will accept the technology.
Lucinda Jackson commented that industries may hesitate to get involved in a research consortium because of perceptions that things move more slowly if EPA is involved and perceptions that industries will be under increased regulatory scrutiny with EPA personnel on site. Fradkin stressed that EPA personnel who participate in these efforts are scientists and engineers from the Office of Research and Development--not regulators. He added that some companies have chosen to conduct their research at federal facilities because they did not want competitors or EPA staff at their facilities.
Tom Wong asked if there is always a need for a formal agreement. Fradkin responded that projects with formal agreements have been the most successful. Formal agreements enhance the sense of commitment among the parties involved, and they help address issues of patents and liability.
Lou Licht asked how quickly a group can be pulled together. Fradkin responded that, after a group has convened and developed its proposal and scope of work, and once participating companies are on board, EPA and participating groups can generally complete the necessary paperwork in 60 to 90 days.
Another participant asked if DOE can write CRADAs, and if there are
differences among other agencies' CRADAs. Fradkin stated that all Federal
agencies except NASA have the authority to write CRADAs; however,
different agencies may have different constraints. EPA can include other
agencies within its own CRADAs. There are currently between 6,000 and
7,000 CRADAs in the Federal government.
GROUP WORK SESSION
RESEARCH PRIORITIES
Workshop participants suggested the following list of items for future research:
The group then attempted to distill the list by merging similar elements. Steve Rock suggested merging some of the modeling components. Lucinda Jackson suggested combining elements on the list to create an "ecological evaluation/environmental benefit" category. William Albright, Desert Research Institute, suggested combining elements to create a category a "revegetation/plant succession" category. Glenn Wilson commented that monitoring and modeling need to be tied together.
Lou Licht suggested developing a list of regulatory impediments to phyto caps. Tom Wong stated that regulatory issues fit with the discussion held earlier in the workshop and are distinct from research needs and priorities. He suggested that technical issues need to be addressed and data developed before lobbying for rule changes. However, participants generally agreed with Licht and asked that regulatory impediments be added to the list.
The group used a multi-voting process to rank the items on the list and came up with the following prioritized list of areas for future research:
Tom Wong suggested that the group expand on the elements that fall
naturally into each of these categories.
Biological Evaluation and Net Environmental Benefit
Lou Licht stated that time is critical, and we cannot afford the luxury of a 50-year study. Lucinda Jackson suggested that initial investigation should focus on existing sites.
Tom Wong suggested including food chain contaminants and risk assessment endpoints in the research category.
Lucinda Jackson said she would like to see data developed to support net environmental benefit analysis.
Jay Anderson, Idaho State University, stated that data needs in this area will be site-specific. In some cases, the question might be, "How will plant communities change over time?" In other areas it may be, "What species should we be using?" or "What is the habitat for a particular endangered species?"
Jody Waugh commented that EPA may be proscribing a solution without defining the problem. EPA should develop a user-friendly process, such as a decision matrix. The process should be ecosystem-based to help understand the interaction of potential contaminant release processes and the risks associated with those releases.
Greg Richardson suggested that it might be useful to look at the decision pathway that the Army Corps and EPA have jointly developed for contaminated dredge sediments. However, using the decision pathway to determine the appropriate assessment endpoints has proven to be a problem.
Paul Schroeder stated that agreement is needed on endpoints and on a
technical framework for the ecological evaluation (for example, an
ecological risk assessment).
Equivalency for Alternatives
Steve Rock suggested that the first step is to agree on vocabulary and a definition of equivalency. Questions that need to be answered include:
Glenn Wilson commented that once we agree on a definition of equivalency, we need to determine regions of applicability, then assimilate and analyze the data.
Paul Schroeder commented that equivalency cannot be demonstrated without
modeling. He asked if the group had concerns about equivalency beyond
those associated with ground-water contamination.
Modeling
Steve Rock asked if we need to develop new models or revise existing ones. Paul Schroeder responded that it would be preferable to develop a single tool that is easy to use, generally accepted, and meaningful to regulators. Glenn Wilson disagreed. He stated that a suite of models is needed. He added that there needs to be a willingness to accept different models.
Craig Benson stated that what is most needed is guidance on how to select the appropriate model for the job.
Bridgette Scanlon, University of Texas, commented that regulators do not have the expertise to evaluate models but that this should not stop people from using complex models. Steve Rock responded that the average regulator lacks the time to develop expertise on a variety of models.
Paul Schroeder reiterated his view that there needs to be a single, screening-level model.
Craig Benson noted that, when you rely on only a single model, the model is used initially as a screening tool but ends up being used as the decision-making tool.
Greg Richardson commented that there is inadequate field verification of what has been modeled. If more elaborate models are developed, more elaborate quality assurance programs will be needed to verify that what was modeled was built in the field.
Bridgette Scanlon stated that monitoring should be added to verification of models. For some sites, there is inadequate data to run any model. We need to consider uncertainty and bounding calculations.
Glenn Wilson added that collecting and analyzing data need to be given
equal priority to modeling.
Regulatory Impediments
Felix Flechas said that applicants must decide whether the treatment is intended for a cap or for another purpose before approaching the regulator. A plan for planting trees on top of a waste site is not a plan for a cap, because it will not provide the functions of containment, isolation, or entombment. ET caps, however, do provide these functions. The Union Carbide site in Texas that John Fletcher discussed is a treatment alternative, but not a cap. This approach may be valid, but it will not meet equivalency. If a new regulatory definition could be developed for a "treatment cap," then there would be a regulatory niche from which such a proposed treatment could be evaluated. Closure has a very definite regulatory objective, and treatment is not part of this objective. Treatment occurs prior to closure. However, in the case of solid waste management units, you can have treatment occurring as part of the corrective action after the unit has ceased to operate. But, again, the treatment is a remediation step, not a closure step.
Chris Rhyne of EPA's Office of Solid Waste commented that regulations do allow for extended closures. The regulator needs to be confident that what occurs during the extended closure period will not further degrade the environment. Permit writers need to be assured that the alternative cap provides the same level of protection and risk reduction as a traditional cover. Rhyne added that he believes the current regulations are flexible, but we are not yet creative enough to implement alternatives. Some changes to existing regulations could also be useful.
Tim Bent of Bridgestone-Firestone stated that ARARs have turned out to be the major regulatory impediment for the two sites on which he is working. He stated that EPA needs to be willing to waive ARARs.
Paula Estornell commented that we should avoid using the term "caps" for alternative covers. She also stated that we could be "shooting ourselves in the foot" if we try to represent alternative covers as equivalent in any way to the traditional, low-permeability RCRA caps.
Lucinda Jackson stated that regulations consider only risks and not benefits and that this is an impediment.
Felix Flechas stated that a regulatory niche in lieu of capping might be
to propose in situ treatment to lower toxicity and mobility of
the contaminants present.
NEXT STEPS
Steve Rock asked workshop participants to focus on immediate next steps and action items.
Larry Fradkin suggested that the group focus on the best way to attack the questions raised during the workshop. He asked the group if it would make sense to conduct field demonstrations.
Mark Ankeny suggested the short-term goal of developing a primer that describes and defines the elements of different alternative covers.
Steve Rock suggested that the group identify demonstration sites within representative climates and that these sites be fully monitored. He suggested the F. E. Warren Air Force Base site as a possible project representative of a semi-arid, high-altitude environment.
Jay Anderson commented that we need to take advantage of existing research projects and see where these sites might be used to fill data gaps and create demonstration sites.
John Fletcher urged the group not to be biased toward 3-year project sites that use fast growing plants. He stated that it would be important to include naturally revegetated sites among the demonstration sites.
Tim Bent commented that data from existing sites are not widely available. He added that a primary goal should be to assemble existing data and make it accessible.
Steve Rock asked participants if they thought that more field work is needed.
Paul Schroeder stated that we need to establish a technical framework that identifies how to evaluate these systems. He also suggested that it would be useful to conceive and implement a demonstration site from beginning to end.
Greg Richardson cautioned against confusing ET barrier systems with treatment alternatives. He added that we already have abundant data on ET systems, and an ET barrier system can be approved today on anything but a RCRA Subtitle C commercial landfill.
Workshop participants discussed sites that may serve as potential demonstration projects. Greg Harvey of the U.S. Air Force mentioned a site in Tulsa, Oklahoma, for which the Air Force is considering a vegetative cover. Tim Bent stated that he is working on two Superfund sites that might also work as demonstration projects. Lou Licht identified sites of his in Oregon, Virginia, and Iowa as possible demonstration projects. Jody Waugh suggested 2 sites in Utah with ET covers: one in Monticello and another in Ogden.
Brain Andraski, U.S. Geological Survey, suggested a site in Beatty, Nevada. Tom Wong suggested Union Carbide's 1-acre site as a treatment demonstration.
Michael Fayer of Pacific Northwest National Laboratory suggested establishing a mechanism--a Web site, for example, or a committee--for collecting and sharing information. He also suggested establishing a technical advisory board, which would provide standardized reviews of alternative cover proposals.
William Albright discussed letters from heads of waste disposal agencies in all 11 western states. These individuals have offered their cooperation in identifying commercial operators willing to participate in cover demonstration programs.
Steve Rock asked participants if they were interested in ET/water barrier sites only or treatment sites only. The group expressed a strong desire to continue working on both types of sites.
Steve Rock asked who among the workshop participants wanted to be a player in future efforts. He suggested forming a group that would set up and standardize demonstration projects, funnel resources into areas such as monitoring and modeling, review documents, and pursue additional resources. He added that such a group would be a persuasive proposal writing team.
Tom Wong asked if it might be appropriate to break the RTDF Phytoremediation of Organics Action Team into two subgroups, one focused on phytoremediation of organics and the other on alternative caps.
Chris Rhyne of EPA/OSW stated that OSW would be the office responsible for making regulatory changes. He added that OSW management is probably unaware of many of the concerns about regulatory impediments discussed during the workshop. He stated that he would bring these concerns to the attention of EPA management.
Two subgroups were formed: a Demonstration/Design Subgroup, and a Modeling/Monitoring Subgroup.
Steve Rock noted that one of the first tasks of each subgroup would be to synthesize existing information. Phil Sayre suggested that each subgroup hold an initial conference call. After that, the subgroups should contact site owners to determine their interest in participating in demonstration projects.
Jay Anderson suggested that the proceedings of the landfill capping conference held in Jackson might be a useful starting point for people. He suggested that people e-mail him if they would like a copy.
The following individuals signed up for the Modeling/Monitoring Subgroup:
Paul Schroeder
Jeff Smith
Scott Potter
Craig Benson
Bridgette Scanlon
Glendon Gee
Mike Fayer
Bill Albright
Glenn Wilson
Jody Waugh
Mark Ankeny
Brian Andraski
The following individuals signed up for the Demonstration/Design Subgroup:
Ross del Rosario
Lou Licht
Greg Mellema
Robert Shelnutt
Bob Tossell
Craig Benson
Bridgette Scanlon
Glendon Gee
Greg Harvey
John Fletcher
Glenn Wilson
Bill Albright
Jay Anderson
Jody Waugh
Tim Bent
Mark Ankeny
Brian
Andraski
Alternative Cover
Assessment
Project Workshop
Cincinnati Bell Long Distance Center
Room 1803
Cincinnati, Ohio
September 24-25, 1997
Final Attendee List
|
William Albright Jay Anderson Brian Andraski Mark Ankeny Craig Benson Tim Bent David Carson Ross del Rosario Steve Dwyer Paula Estornell Michael Fayer Felix Flechas John Fletcher Glendon Gee Greg Harvey Lucinda Jackson Marty Kosec Fran Kremer Louis Licht |
Kelly Madalinski Greg Mellema William Brent Nixon Matthew Peak Scott Potter Chris Rhyne Gregory Richardson Steve Rock Phil Sayre Bridgette Scanlon Paul Schroeder Robert Shelnutt Ken Skahn Jeff Smith Steve Smith Robert Tossell W. Jody Waugh Glenn Wilson Tom Wong |
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