SUMMARY OF THE REMEDIATION TECHNOLOGIES DEVELOPMENT FORUM
PHYTOREMEDIATION OF ORGANICS ACTION TEAM MEETING

Omni Houston Hotel
Houston, Texas
June 23, 1998

WELCOME AND OVERVIEW

Lucinda Jackson (Chevron Corporation) and Steve Rock (U.S. Environmental Protection Agency [EPA]), the two co-chairs for the Remediation Technologies Development Forum (RTDF) Phytoremediation of Organics Action Team, opened the meeting by welcoming participants (see Attachment A).

Rock noted that the RTDF was created to provide a forum in which industry, governmental agencies, and academic institutions can work together to develop and improve environmental technologies that will remediate sites in the safest and most cost-effective manner. The RTDF, Rock continued, fosters public- and private-sector partnerships to undertake the research, development, demonstration, and evaluation efforts needed to achieve common cleanup goals. Without the RTDF, Rock noted, antitrust laws would prevent members of the same industry from working together. Seven RTDF Action Teams have been formed:

Information about all seven teams can be found on the Internet (http://www.rtdf.org).

The Phytoremediation of Organics Action Team was established in 1997. As Jackson noted, the Team's goal is to develop and validate plant use as a means for remediating organic wastes in soil and water. Input from industry, academia, and government representatives provide the Team with various technological, environmental, regulatory, and business viewpoints. Given its wide focus, Jackson explained, the Team has divided into three subgroups:

• Total Petroleum Hydrocarbon (TPH) in Soil
• Vegetative Caps/Alternative Cover Assessment
• Trichloroethylene (TCE) in Ground Water

Leaders from each subgroup briefly explained their activities. Later in the conference, the participants segregated into the three Subgroups. (Information on each subgroup appears later in this summary.)

Rock noted that two of the Subgroups—TPH in Soil and Vegetative Caps/Alternative Cover Assessment— share many similarities. More important, he said, both are at the brink of signing a Cooperative Research and Development Agreement (CRADA) to formalize their groups. Rock stressed that a CRADA differs greatly from a grant. With a grant, he said, parties that contribute money have little control over how funds are spent. With a CRADA, however, parties that contribute money or in-kind services directly impact resource allocation decisions. Rock said a CRADA is more like a partnership than a contract, but he warned participants to remember that signing a CRADA carries legal ramifications.

Rock talked briefly about the benefits of CRADAs. He said that CRADA participants can review and validate data before the data are released to the public. Also, Rock said, the CRADA offers anonymity, which means the names of site owners and site locations are not released. Additionally, he continued, CRADAs can be designed to protect proprietary information. Rock said several other benefits are associated with joining but that they differ depending on the Subgroup. These Subgroup-specific benefits are discussed later in this summary.

Rock distributed sample CRADAs for the TPH in Soil Subgroup and the Vegetative Caps/Alternative Cover Assessment Subgroup. Referring to these documents, Rock said that the CRADA basically outlines key definitions, a statement of work, a time table, a list of responsibilities and commitments, and a signatory page. He said that several clauses in the CRADA are negotiable. Ideally, he said, he hopes that each Subgroup can identify a set of clauses that will satisfy all signatories. Rock said the CRADA protects most people's rights and that release and termination clauses are written into the contract. Terry McIntyre asked whether Canadian organizations can participate. Phil Sayre said he did not foresee any obstacles, because the EPA has a Memorandum of Understanding (MOU) with Canada.

TOTAL PETROLEUM HYDROCARBON IN SOIL SUBGROUP

The TPH in Soil Subgroup is co-chaired by Lucinda Jackson and Phil Sayre (EPA). Sayre opened the discussion by explaining that the Subgroup's goal is to determine how effectively plants (e.g., grasses, legumes, and trees) degrade aged petroleum hydrocarbons across a range of geographical locations and climatic conditions. The Subgroup realizes, Sayre said, that test demonstrations must generate data that regulators will accept. In an effort to produce a strong data set, Sayre continued, the Subgroup is creating a standardized field test protocol for TPH Subgroup members. Researchers who do not meet the minimum protocol requirements, he explained, will not benefit from the RTDF's resource leveraging.

Review of the Standardized Field Test Protocol

Jackson told participants that the Subgroup is creating a standardized field test protocol. A working draft of the protocol, entitled "Phytoremediation of Petroleum Hydrocarbons in Soil," is on the RTDF Website. Summarizing the protocol, Jackson said each test site will have four randomized test blocks. Each block will contain the following three plots:

• Unplanted control. Jackson said this treatment plot will be kept weed free. She said the Subgroup has listed RoundUp as its first choice for weed control. According to Jackson, most participants feel this herbicide would not impact microbial populations.
• Native plant species plot.
• Standardized mix of rye, legume, and fescue. One participant questioned the usefulness of the standardized mix. Jackson said it will provide data that will help researchers compare phytoremedial effects across the country. Jackson noted that the protocol allows great flexibility. For example, while the protocol offers seeding proportion recommendations, it does not specify which species of grass, fescue, and legume to use. Duane Wolf agreed that a standard mix is important as well as practical. He said that investigators know where to find grass, fescue, and legume seed, and they already know how to optimize growing conditions for these plant types. As an added plug for the standard mix, Jackson said she is eager to start generating a database for grasses because some studies indicate that grasses are the most effective biodegraders.

Jackson said that each of the 12 plots (i.e., 3 plot types x 4 replications) should be at least 20 x 20 feet. To determine where to establish the plots, at least 20 randomly dispersed soil samples will be collected as part of an initial site characterization soil sampling event (T_I). All the T_I samples, Jackson noted, should be collected from a depth of 0 to 6 inches.

After the plots are established, Jackson said, soil samples will be collected from two depths: shallow (0 to 6 inches) and deep (6 to 18 inches). During the field test sampling, one composited sample (generated by mixing 8 core samples) will be collected per plot for each depth interval (totaling 12 samples for a given depth) when planting activities are initiated (T₀), after 6 months (T₁), 18 months (T₂), and 30 months (T₃). Jackson and Ernie Lory noted that these sampling times are rough outlines and may need to be modified depending on where and when projects are initiated. The sampling times were originally generated assuming the plots would be planted in the spring. If the plots are planted in the fall, the T₁ sample should be collected after 6 months in areas with warm winters but after 1 year in areas with cold winters.

Jackson stressed that shallow samples must be analyzed upon collection. For deep samples, the protocol recommends saving and archiving T₁ and T₂ samples. Jackson said these samples will only need to be analyzed if interesting changes are detected between the T₀ and T₃ sampling events. David McMillan questioned this approach, noting that a more meaningful trend analysis could be performed if three, rather than two, data points are generated.

As an aside, McMillan recommended archiving all soil samples rather than just the deep T₁ and T₂ samples. If all samples are archived, he noted, they could be reprocessed years later should more sophisticated and accurate analytical techniques become available. He said the samples could be freeze dried, air dried, or frozen.

Soil sample analyses include:

• Agronomic analyses. Jackson said that samples will be analyzed for pH, salinity, nutrients, texture, organic matter, and soil type. These analyses, she stressed, will help researchers optimize growing conditions by determining whether plots need fertilizer or lime. One conference participant asked whether the Subgroup had established fertilizing guidelines. During a conference call (May 29, 1998), the Subgroup discussed this issue but did not resolve it. At this point, Jackson said, the protocol simply recommends fertilizing as needed to keep plants healthy and thriving.
• Hydrocarbons.
  • TPH. Evelyn Drake noted two methods that can be used to test TPH: (1) GC and (2) hexane extraction.
  • Polyaromatic hydrocarbons (PAH). Drake said that Arthur D. Little (ADL) and Batelle's cost estimate includes analyses for 16 parent PAHs. It does not, however, include a detailed breakdown of alkylated and aliphatic hydrocarbons. Drake said that researchers who want this breakdown must pay additional fees. Drake noted that some cleanup sites might have high TPH but very low PAH concentrations. If the T_I sampling indicates that PAH concentrations are below cleanup requirements, PAH analysis will not be required during subsequent sampling events.
  • Biomarkers. Lory asked whether the biomarker analysis applies to Bunker C oil. Following Lory's question, Steve Geiger asked whether biomarkers can be used for town gas sites. Drake said she would respond to Lory's and Geiger's questions after researching the topic. One participant noted that ADL's cost estimate was based on a hopane analysis. The participant asked whether ADL's price would increase if a different type of biomarker were analyzed. Drake did not think so.
• Microbial analysis. Drake said that microbial analysis is being performed to determine whether hydrocarbon removal is correlated to elevated microbial populations. Sayre noted that many Subgroup participants plan to perform the microbial analysis in house. Sayre briefly described the microbial analysis technique outlined in the protocol. He said the process uses site-specific oils (those extracted from site soil) and an MPN technique to evaluate degrader populations by analyzing sheen breakup and solution cloudiness. Albert Vendosa questioned whether the Subgroup has identified the best methodology. First, he strongly recommended using Redox dye. Second, he recommended consulting a paper in the 1986 edition of the Canadian Journal of Microbial Analysis. Vendosa agreed to post the paper's reference on the RTDF Web site.

Jackson said the protocol recommends analyzing plant shoots for hydrocarbons during the T₃ sampling event. Drake explained that this analysis will show whether there is a link between hydrocarbon degradation and plant uptake. Also, Jackson noted, the protocol recommends performing plant assessments to analyze for percent vegetative cover, shoot mass, and rooting characteristics (e.g., root density and root depth). Jackson recommended performing the assessment annually, during soil sampling events.

Jackson explained that the protocol contains several attachments that expand on (1) seeding mixture; (2) soil sample collection; (3) vegetation sampling, storage, and shipping method; (4) microbial analysis; and (5) plant assessment. The protocol does not yet include an attachment outlining root sampling techniques and root storage. Drake said ADL could provide one.

Criteria for Joining the TPH Subgroup

Sayre said that he hopes to formalize the Subgroup by having participants sign a CRADA within the next few months. He said participants can sign at different times but that all field demonstration projects will need to be initiated by spring 1999. According to Sayre, all signatories must agree to:

• Commit for 3 to 4 years. Jackson stressed that the 3-year commitment is a minimum requirement. Ideally, she noted, the commitments will be longer term, such as 5 years.
• Participate in periodic conference calls and attend annual or biannual meetings.
• Provide test sites.
• Adhere to the minimum requirements outlined in the protocol. Ideally, Jackson said, it would be best if participants adhered to all recommendations in the standardized protocol. She noted, however, that a candidate might be admitted into the Subgroup even if he or she could not meet all recommendations. Conference participants discussed which parts of the protocol should be mandatory and which should be optional. After a long discussion, participants agreed that all participants who are performing field tests must:
  • Include four replications of all three treatment types. Initially, Jackson recommended making the native mix optional, but participants opposed this idea.
  • Collect soil samples at Times I, 0, 1, 2, and 3. Originally, Jackson recommended making the T₂ sampling event optional, but participants also opposed this idea.
  • Have hydrocarbon analyses analyzed by a Subgroup-endorsed laboratories. Drake noted that the Subgroup has endorsed ADL and Batelle as laboratories that can perform hydrocarbon analyses. Drake said participants can use other laboratories if those laboratories prove competent. Drake said the Subgroup is generating a test standard. If another laboratory can produce accurate results using the standard, the Subgroup would allow the laboratory to participate.

Jackson listed the following as optional:

• Establishing visual aids. Lory recommended placing small, unispecies plots on each test site. He said these plots would serve as visual aids that could help nonbotanists identify plants. Jackson agreed this was a good idea and said Chevron plans to do this. She said she would write this recommendation into the protocol.
• Hydrocarbon analysis of plant shoot samples. Jackson questioned whether all participating test sites must perform the plant shoot hydrocarbon analysis. Jackson said Chevron will conduct the analysis and suggested that one or two other sites do the same. Some participants thought the analysis should be mandatory at all sites. Participants agreed the issue could be resolved later; the shoot samples are scheduled for collection in 3 years.
• Plant assessment.
• Microbial analysis. Jackson said her company is concerned only with endpoints and is not really interested in showing why phytoremediation works. Sayre said that showing the link between microbial populations and hydrocarbon reduction will help gain regulatory approval. Jackson agreed but thought evidence could be gathered by using just a few sites rather than all test sites. In general, the participants agreed that microbial analyses could be eliminated if budgets are highly restrictive. Drake warned, however, that an initial microbial analysis is useful because it can steer researchers from performing tests where degrader populations are excessively low.

Participants agreed that the optional analyses should be ranked in the following order of importance: (1) plant assessment, (2) hydrocarbon analysis of plant shoots, and (3) microbial analysis. In addition to these analyses, conference participants said several other studies and analyses (e.g., FAME analysis, bioavailability analysis, plant toxicity studies) could augment the Subgroup's efforts. Drake said the Subgroup would be delighted if academic institutions decide to perform some of these ancillary studies. Sayre agreed but stressed that these efforts would have to be conducted outside the RTDF framework. Drake asked whether RTDF reports could refer to these ancillary efforts. Sayre did not foresee this being a problem.

• Offer a financial and/or an in-kind service contribution. The following table summarizes the costs associated with a test demonstration.

* Deep samples collected during T₁ and T₂ will be archived. Therefore, they are not included in the total number of samples calculated.

Jackson noted that the preceding requirements are for members who are planning to establish field demonstrations. She said parties without test sites will be allowed into the CRADA if they offer financial contributions of $20,000.

Sayre encouraged participants to contact him (phone: 202-260-9570; e-mail: sayre.phil@epamail.epa.gov) for additional information on joining the CRADA. He said that specific contractual questions could be forwarded to EPA's Larry Fradkin.

Benefits of Joining the CRADA

Sayre noted that people who join the TPH Subgroup will receive several benefits, including:

• Reduced sample costs. Normally, Drake said, hydrocarbon analysis (i.e., TPH, PAH, and biomarkers) costs about $575 per sample. Because the RTDF Subgroup is receiving a discounted rate, soil samples will be processed for about $300 per sample.
• Central data collection and uniform data processing. Sayre said that Kansas State University (KSU) is being hired as a coordinating center for the TPH Subgroup. KSU will gather the Subgroup's raw data, analyze it for quality assurance and quality control, format it, and redistribute it to the entire Subgroup annually. Sayre said that services provided by KSU will be paid, in large part, by TIO.
• Access to a statistician. Sayre noted that the RTDF Subgroup has identified a statistician, Dennis King, who can help answer protocol questions.
• Access to all RTDF site data. Sayre said that all CRADA signatories will have an early look at the data being generated by various research teams within the Subgroup. He said the Subgroup will have a chance to validate the data before it is released to the public.
• Annual site visit from KSU's Peter Kulakow. Sayre said that Kulakow will perform annual plant assessments (e.g., coverage, root depth, root density) and soil assessments (e.g., agronomic analyses). Sayre stressed that this service will be paid, in large part, by TIO.
• Individual field test validation by EPA. Sayre said that data produced within the Subgroup will have EPA's stamp of approval.
• Confidentiality. Repeating Rock's earlier comment, Sayre reminded participants that the CRADA is designed to protect confidentiality.

Site Update

Sayre said that the Subgroup is composed of people from industry, government agencies, and academic institutions. To date, more than 80 people have expressed interest in the Subgroup's activities. Site owners who are considering demonstration projects include oil companies, the Army, and the Petroleum Environmental Research Forum (PERF). Sayre estimated that about 12 sites will be tested under the RTDF Subgroup. Sites that could serve as candidates include town gas sites, treatment farms, and refinery sludge sites. Potential demonstration sites have been identified throughout the country, including Alaska, Ohio, Kansas, and California.

VEGETATIVE CAPS/ALTERNATIVE COVER ASSESSMENT SUBGROUP

The Vegetative Caps/Alternative Cover Assessment Subgroup is co-chaired by Steve Rock and Tom Wong (Union Carbide). Wong opened the discussion with a brief description of the Subgroup's history. Originally, he said, the Subgroup was called the "Vegetative Caps" Subgroup and focused on phytoremediation of organics. Initial conference calls, he continued, focused on defining a vegetative cap. In September 1997, the Subgroup met in Cincinnati, Ohio, and participants decided that a vegetative cap must function as an impermeable cap that prevents water migration to underlying wastes. Today, the Subgroup's focus is three-fold: (1) achieve water balance, (2) improve landfill cover models, and (3) investigate impacts resulting from vegetative uptake. The Subgroup plans to pursue its goals under the Alternative Covers Assessment Program (ACAP). The ACAP is designed to evaluate alternative cover performance across a wide range of geographical locations. The technology's efficacy will be determined by evaluating infiltration prevention.

Rock explained that four objectives are outlined under the ACAP: (1) perform a site survey to identify existing and potential test sites, (2) install monitoring equipment at numerous test sites, (3) devise better numerical models, and (4) produce a guidance document. Ideally, he said, the ACAP effort will help state regulators and EPA officials make decisions regarding alternative covers.

ACAP's Phase I—Site Survey

William Albright (Desert Research Institute [DRI]) said that a questionnaire has been distributed to state agencies in all 50 states and to various federal agencies in an effort to gather information about demonstration site locations. He said responses are inundating his office and stressed that numerous site owners have expressed interest in participating in the ACAP.

Sites that could serve as potential test sites include those (1) with existing landfill covers that are retrofitted for the ACAP project, (2) with covers in the process of installation, and (3) those without waste. Rock said that sites might be municipal solid waste sites, hazardous treatment farms, RCRA, or CERCLA sites and that site owners could include industrial, municipal, and federal (Department of Energy [DOE] and Bureau of Land Management) participants.

ACAP's Phase II—Installation of Monitoring Equipment

Rock distributed a draft monitoring plan. The draft, entitled "Alternative Cover Assessment Program (ACAP): A Proposal to Develop Guidance for the Design and Numerical Evaluation of Alternative Landfill Final Covers," is dated June 1998 and was written by DRI (Albright and Glenn Wilson), the Pacific Northwest National Laboratory (Glendon Gee), and the University of Wisconsin (Craig Benson). The participants discussed the monitoring plan at great length. Issues that generated discussion included:

• Lysimeter. Rock stressed that the goal of the ACAP is to determine whether alternative covers can prevent water from infiltrating waste. After numerous deliberations and a lengthy discussion of pros and cons, he said the Subgroup has decided that drainage lysimeters should be used to measure water infiltration. Rock said the Subgroup knows the limitations of lysimeters but have not identified a better approach.

  Rock noted that lysimeters must be installed fairly deeply so that roots cannot penetrate the lysimeter's liner. Albright said that the monitoring plan recommends installing a net that prevents root penetration into the lysimeter. He stressed that this net should not impede hydraulic flow.

  One participant said that Geraghty & Miller, Inc., has designed a lysimeter that is slightly smaller than that proposed in the Subgroup's draft monitoring plan. The participant noted that Geraghty & Miller, Inc.'s, lysimeter costs about $30,000 to $35,000 for installation and instrumentation.

  Rock said that a lysimeter will be mandatory at all participating ACAP test sites. Whether a site owner wants to install TDR throughout the lysimeter, however, is optional. Rock noted that TDR data will help modelers but will not indicate whether the cap is effective.

• Lysimeter pan slope. Wong noted that the draft monitoring plan recommends placing the lysimeter pan at the same slope as the landfill's natural slope. According to Benson, Albright reported, lysimeters can be built on steep slopes. One participant recommended placing the lysimeter on fairly flat surfaces, noting that steep slopes cause excessive runoff. Albright said the Subgroup might want to consider setting a maximum slope for placement of the lysimeter pan. He recommended 5 percent.

• Lysimeter sidewalls. Participants debated whether sidewalls are needed to calculate the cross-sectional surface area that drains into a lysimeter. Wong said the cross-sectional area equals the lysimeter pan's area. Another participant said sidewalls are needed to calculate the cross-sectional surface area because water does not flow straight down to the pan. Wong said the difference between cross-sectional area and the lysimeter pan's area will be minimal if vertical sidewalls are used. Albright asked whether it would be possible to build vertical sidewalls by excavating the landfill's slope. Rock said that it is very difficult to build a vertical sidewall.

  Assuming that a vertical sidewall cannot be built, Wong asked whether lysimeter sidewalls must be built at a consistent slope across different sites. If the sidewall slopes vary between sites, Wong noted, different capture areas would be produced and could lead to results that are not comparable between sites.

  Some participants said that sidewalls are not needed and noted that side walls could cause preferential flow. Rock said sidewalls could be considered a variable and the decision whether to use them could be determined site-by-site. Albright said sidewalls need not extend to the surface. He stressed, however, that some small sidewall is needed at the bottom of the lysimeter. Without a barrier, Albright feared, some of the moisture that collects on the lysimeter pan could drift off the pan laterally. Rock agreed and suggested that the draft monitoring plan recommend a minimum sidewall depth.

• Runoff collection system. Participants stressed the importance of measuring runoff at test sites. This measurement is required, Rock noted, to calculate water balance.

• Vadose zone monitoring system. Albright said that vadose zone data must be collected for validation of numerical models. He stressed that these models are needed for both engineering and regulatory purposes. Vadose zone data can be collected, he said, using moisture probes, soil water pressure sensors (e.g., tensiometer, heat dissipation, gypsum block), and soil temperature sensors. (One participant questioned whether tensiometers would truly apply to ACAP test sites.) Albright stressed that gathering temperature data would be helpful but that they are not absolutely necessary.

• Gas sampling. Rock stressed the importance of monitoring landfill gases. One participant noted that excessively high gas levels lead to phytotoxicity.

• Drainage water quality. Participants agreed that the recommendation to perform drainage water quality assessments should be eliminated.

• Minirhizotrons. Albright said that minrhizotrons can be used to determine the depth of plant roots. He said the device typically creates a hole that is less than 2 inches and therefore, does not produce a significant intrusion. Participants said the device should be placed outside the lysimeter area if the intrusion exceeds 2 inches.

Rock noted that the draft monitoring plan outlines monitoring choices. Rock said the plan should be modified to provide additional guidance. For example, he said, the plan should tell users which type of instrumentation is best to use under different conditions.

Criteria for Joining ACAP

Rock said that people who sign the CRADA must be prepared to (1) offer a 3 to 5 year time commitment, (2) participate in annual meetings, (3) participate in monthly conference calls, and (4) provide financial (or in-kind services) commitments of $30,000 to 50,000 per year.

Benefits of Signing the CRADA

Rock said that participants who sign the CRADA will benefit from (1) central data collection; (2) a standard monitoring design that will be acceptable to regulators; (3) a cover design review; (4) an annual site visit to calibrate instruments, perform a cover assessment, and analyze whether rodents are burrowing deeply into the cap; and (5) an annual report that will summarize data collected from data loggers. Additionally, Rock said that some field testing costs will be offset by EPA contributions. Already, he noted, EPA has contributed $200,000 and $150,000 to Phase I and Phase II, respectively.

TCE IN GROUND WATER SUBGROUP

The TCE in Ground Water Subgroup is co-chaired by Greg Harvey (U.S. Air Force) and Harry Compton (EPA). Harvey opened the discussion with a brief overview of the TCE Subgroup's goals and activities. He explained why it is important to identify technologies that can remediate TCE, a commonly used degreaser. First, he noted, TCE is fairly ubiquitous in ground water. Second, he said, most of TCE-contaminated ground water (80 percent) is not conducive to natural attenuation.

Harvey cited the following as possible Subgroup goals:

• Expand the Subgroup's focus. Harvey said he would like to broaden the Subgroup's focus to include evaluations of:
  • Additional contaminants. To date, Harvey noted, the Subgroup has focused its attention on TCE studies. In the future, Harvey said he hopes to investigate additional ground-water contaminants, like tetrachloroethylene (PERC) and carbon tetrachloride.
  • Additional plant species. Poplars have been used in most phytoremedial studies. Harvey would like to evaluate a broader set of plant species. Specifically, he said he wants to build on DOE's biomass screening project to determine which plants grow best in different regions. Harvey listed alfalfa and marsh grasses as potential phytoremedial plants. Lazlo Marton (University of South Carolina) noted that he is working with marsh grasses and has found them to be hearty under harsh growing conditions. Marton agreed to contact researchers who are using marsh grasses at coastal sites.
  • Waste streams. Harvey said that phytoremediation should be considered for waste streams rather than just classic spills.
• Field projects at PERC sites. Harvey said the Subgroup is investigating the possibility of conducting field work at dry-cleaning facilities.
• Evaluate geochemistry. Harvey would like to evaluate the geochemistry of phytoremedial test sites.
• Create a standardized protocol. To be able to compare results across the country, Harvey noted, it is important that researchers use the same growing and measuring techniques.

Harvey said that the Subgroup is composed of people from industry, government agencies, and academic institutions (i.e., University of Georgia, Kansas State University, Iowa State, Texas A&M, and the University of Washington). Harvey noted that the Subgroup would like to expand on ongoing field studies at the Edward Sears site, Carswell AFB, Aberdeen Proving Grounds, and Hill AFB. He also said that the Subgroup has already become involved with a NATO CCMS case study and a project the Army is considering in Washington. Participants listed the following as additional sites that might interest the Subgroup:

• Santa Monica site. According to Jerry Schnoor (University of Iowa), a huge site in Santa Monica is contaminated with TCE.
• DOE sites. One participant noted that many DOE sites (e.g., Hanford) are contaminated with TCE. Participants agreed that the Subgroup should contact DOE's Rashalee Levine to determine why this agency has not shown more interest in phytoremedial technologies.
• Cape Canaveral. According to Schnoor, Lou Licht recently initiated a phytoremedial project.
• CERCLA sites. Harvey noted that CERCLIS 3, a database, lists TCE-contaminated CERCLA sites. Dawn Carroll (TIO) agreed to examine the database for potential sites.

Harvey stressed that the Subgroup must start working toward their goals. Before studies can be initiated, funds must be generated. Harvey recommended seeking partnerships with industries and organizations with financial backing (e.g., the Chemical Manufacturer Association [CMA], dry cleaners, the large appliance industry, automobile companies, ALCOA, and other metal companies). Harvey agreed to pursue additional contacts with industrial representatives.

Harvey encouraged participants to learn more about the Subgroup and recommended reading Jonathan Chappell's paper, entitled "Phytoremediation of TCE in Ground Water Using Populus," for a synopsis of the technology. (This paper is on the Internet at http://clu-in.org/pub1.htm).

Attachment A
Attendee List