SUMMARY OF THE REMEDIATION TECHNOLOGIES DEVELOPMENT FORUM
PHYTOREMEDIATION ACTION TEAM
TOTAL PETROLEUM HYDROCARBON IN SOIL SUBGROUP
CONFERENCE CALL

January 20, 2000
12:00-1:00 p.m.

On January 20, 2000, the following members of the Remediation Technologies Development Forum's (RTDF's) Phytoremediation Action Team, Total Petroleum Hydrocarbon (TPH) in Soil Subgroup, met in a conference call:

Lucinda Jackson, Chevron Corporation (RTDF Action Team Co-Chair and Subgroup Co-Chair)
Phil Sayre, U.S. Environmental Protection Agency (EPA) (Subgroup Co-Chair)
Kathy Banks, Purdue University
Evelyn Drake, Exxon Research and Engineering
Steve Geiger, ThermoRetec, Inc.
Sam Jackson, State University of New York
Peter Kulakow, Kansas State University
Royal Nadeau, EPA
Bud Prevatt, Phillips Petroleum Company
Steve Rock, EPA
David Tsao, BP Amoco
Duane Wolf, University of Arkansas

Also present was Christine Hartnett of Eastern Research Group, Inc. (ERG).

UPDATE ON FIELD DEMONSTRATION SITES

The TPH in Soil Subgroup has created a field study program to evaluate how effectively plants degrade petroleum hydrocarbons across a range of test sites. Peter Kulakow said that he distributed site questionnaires to all Subgroup members who are involved with demonstration sites. He has received responses for all but one site. The responses have been distilled and summarized, Kulakow said, in a "Status of Field Sites" chart, the most up-to-date version of which was sent to Subgroup members before the conference call. Kulakow said that the chart needs revision because it does not reflect recent work that has been conducted at Sites C, D, and E. He asked conference call participants if they had updates to provide on any other Subgroup sites. They offered the following:

• Update on research agreements. Steve Rock said that Cooperative Research and Development Agreements (CRADAs) have been signed for Sites A, B, F, and K. He was not sure of the status of the agreements for Sites H, I, and J, but he agreed to check on this. He said that CRADAs are not being sought for Sites C, D, E, or G and that the "Status of Field Sites" chart should reflect this--Kulakow should enter NA (not applicable) under the chart's "Research Agreement with EPA" column.

• Update on activities at Site K. Rock said that data collected from Site K are being reviewed for quality assurance.

• Update on activities at Site J. Duane Wolf described activities at Site J, a well-head complex surrounded by a 1-foot berm. He said that he was not required to obtain regulatory approval at this site; the site's owners have assured him that he has full permission to pursue phytoremedial activities. (Rock recommended looking up the name of the site's regulator in case he/she needs to be consulted in the future.) Wolf said that time initial (T_i) and time zero (T₀) samples have been collected. The former are being analyzed in-house, he said, but the latter will be sent to the Arthur D. Little (ADL) laboratory for analysis. Fall season grasses have been planted at Site J, Wolf reported, noting that these have germinated and are growing strong. In the spring, the site will be replanted with warm-weather species. Greenhouse studies are being conducted to determine which of the warm-weather species will perform most effectively at Site J. Wolf described two of the plants--Bermuda grass and a hybrid crab grass--that are currently being evaluated. The Bermuda grass appears to be effective, he said, but is difficult to grow from seed. If Bermuda grass were applied to the field, he said, test plots would probably have to be sprigged. (Subgroup members said that sprigging is a reasonable and viable approach that is often used for Bermuda grass. Kulakow said that Bermuda grass can also be established by rolling it onto sites as turf. It may be possible, he said, to find a company that will donate the turf.) Wolf said that the hybrid crab grass is exhibiting robust growth in the greenhouse and is also being considered for field study. Evelyn Drake asked whether the Bermuda grass and the crab grass have comparable root systems. Wolf and Kulakow provided an answer, saying that crab grass roots may extend to greater depths, but that they do not persist as long as Bermuda grass roots. (The crab grass dies back each year, but Bermuda grass is a perennial.) Wolf said that FAME analysis has been performed on the crab grass; the results show that an extensive microbial community is associated with the root system.

Kulakow thanked the participants for their updates, noting that he will use the information to revise the "Status of Field Sites" chart. In the revised version, Kulakow said, he will propose a new way of labeling sampling events.

COST-TRACKING SPREADSHEETS

Steve Geiger said that he, Kulakow, and Phil Sayre created two cost-tracking spreadsheets and distributed these to Subgroup members before the conference call. One of the spreadsheets, he explained, is designed to track the costs of Subgroup field demonstration projects; the other is designed to predict the costs of full-scale phytoremediation projects. Lucinda Jackson asked whether it is realistic to expect Subgroup members, who are conducting demonstration projects, to predict costs for full-scale projects. She said that simple extrapolations cannot be made between demonstration and full-scale projects because the former require multiple field replications and much more extensive analytical activities. Subgroup members acknowledged the challenges associated with predicting full-scale costs, but they agreed that it must be done. Conference call participants said that the Subgroup will not serve as a sole pioneer in this effort; full-scale phytoremediation costs have already been estimated by the Petroleum Environmental Research Forum (as part of the PERF 9413 project) and by Kathy Banks (as part of the Craney Island project).

Geiger said that the Subgroup's spreadsheets are modeled after a Federal Remediation Technology Roundtable (FRTR) cost-tracking spreadsheet that is being used for a wide variety of technologies. The Subgroup's spreadsheets, Geiger said, use the same general cost categories as the FRTR spreadsheet does. Within each general heading, however, the Subgroup's spreadsheets list several phytoremediation-specific categories. Geiger asked for feedback on the spreadsheets.

Jackson said that she understands the logic of using FRTR's general cost categories: using this approach will make it easy to compare the costs of phytoremediation with those incurred by other technologies. Nevertheless, she strongly recommended changing one of the headings, arguing that it had been improperly labeled in the first place. She recommended changing the "Capital Costs for Technology" heading to "Startup Costs for the Technology." Subgroup members agreed that the change should be made. Geiger agreed to redistribute the spreadsheets after he incorporates Jackson's suggestion.

Rock expressed praise for the spreadsheets, but said that he was unsure whether they captured costs associated with replanting. Kulakow said that replanting costs had been considered when the spreadsheet was put together. These costs should be entered, under the "Supplemental Planting Stock"category that appears under the "O & M Costs for Technology" heading.

Nadeau asked whether the Subgroup had considered using the Removal Cost Management System (RCMS) as a template for cost-tracking, noting that this system is used regularly by many EPA remedial project managers (RPMs). Kulakow said that it had been considered, but that the Subgroup decided to use the FRTR spreadsheet as a template instead. In the future, Kulakow said, it might be possible to modify the RCMS to accommodate phytoremediation technologies.

ANNUAL REPORT

Kulakow said that he expects to complete the Subgroup's annual report by the end of February 2000. The report will be split into eight sections: (1) Overall Summary, (2) Technology Description, (3) Site Description, (4) Matrix Description, (5) Status of Field Sites, (6) Summary of First-Year Plant Growth, (7) Cost Estimation, and (8) Issues Discussion. Kulakow said that these headings generally follow those provided in FRTR's Guide to Documenting and Managing Cost and Performance Information for Remediation Projects.

Data Analysis and Presentation

Kulakow said that T₀ data will be analyzed and described in the annual report's "Matrix Description" section. Kulakow said that he currently has T₀ data for Sites A, B, F, and G, but that he hopes to receive data from additional sites before releasing the annual report. Using the data he has collected so far, Kulakow has created two summary tables. These list the overall means and standard deviations of contaminant concentrations at two different depths. One of the tables summarizes TPH concentrations as measured by gas chromotography/flame ionization detection; the other summarizes totals for priority pollutant polycyclic aromatic hydrocarbons (PAHs). Kulakow said that the tables indicate the following:

• Sampling depths range across sites. At each Subgroup field site, Kulakow said, samples are collected at two depths: shallow and deep. At Sites A, B, and G, he said, shallow sampling depths are considered to be about 0 to 15 centimeters. At Site F, however, the shallow range extends down to 20 centimeters. As for the deep range, Kulakow continued, Sites A and G have been collecting samples from the 15- to 45-centimeter range, but Site F is collecting them from 20 to 40 centimeters. At site B, deep sampling depths vary a great deal.

• There is a wide range of TPH values across the sites. While TPH concentrations are fairly low at some sites, Kulakow said, they reach high levels at others.

• The stratification of contaminants with depth varies across the sites. At Site A, Kulakow said, contaminant concentrations increase significantly with depth. Such stratification is not as apparent, however, at Sites B and G.

Kulakow asked conference call participants whether there are additional analyses that should be included in the annual report. Subgroup members recommended including:

• A weathering ratio. Drake said that the annual report should indicate the degree of bioremediation that took place before the Subgroup initiated field activity. Kulakow agreed to include data that express weathering ratios in the report. (He said that he has already started thinking about how to present this.)

• A table that breaks down T₀ data by treatment. Jackson asked Kulakow to include a table that depicts T₀ data by treatment. He agreed to create tables of this sort for TPH and total PAH data. Subgroup members agreed that these tables will provide a useful summary of baseline conditions.

The "Issues Discussion" Section

Kulakow said that the annual report's "Issues Discussion" will feature some of the hot topics that the Subgroup has debated and discussed. He said that he plans to include discussions on fertilization, mowing, microbial assessment, plant selection, the TPH Criteria Working Group (TPHCWG) methodology, and biomarkers. Expanding on the latter, Jackson said that she and Kulakow have scheduled a conference call with ADL to discuss biomarker issues. The call's topics will include normalizing data, choosing biomarkers, and deciding whether the same biomarkers should be used at all Subgroup sites. Kulakow encouraged Subgroup members to spend some time thinking about these issues.

Kulakow asked whether additional topics should be covered in the "Issues Discussion" section. Conference call participants suggested addressing regulatory issues. Two subtopics were identified:

• Regulatory approval. It was agreed that the annual report should contain a brief and general discussion about regulatory approval rather than providing a detailed explanation of the CRADAs. As noted by Jackson and Sayre, readers simply need to get an idea of the steps that Subgroup members took to gain regulatory approval at each test demonstration site. Conference call participants agreed to send Kulakow sentences or brief paragraphs explaining how they obtained regulatory approval. Kulakow agreed to distill this information into one or two paragraphs. Conference call participants said that this would be sufficient, although some noted that it would be nice to present more detailed information in future annual reports.

• Cleanup or risk criteria. Sayre asked whether the annual report should include information about cleanup criteria. Royal Nadeau said that cleanup criteria will probably differ widely across sites depending on the regulators who are involved. He said that some regulators may simply defer to state-published soil cleanup criteria (which vary markedly from state to state); some may focus solely on benzene, toluene, ethylbenzene, and xylene; and others may use risk-based analyses to set site-specific screening levels for TPH. Picking up on the latter point, Kulakow said that the Subgroup is using the TPHCWG methodology to calculate site-specific cleanup levels. To date, he said, TPH data from four sites (Sites A, B, F, and G) have been collected in accordance with the TPHCWG methodology. Conference call participants encouraged Kulakow to include available data sets in the report along with an explanation of how site-specific cleanup goals can be produced using the Risk-Based Corrective Action (RBCA) framework. Kulakow said that he would be happy to do this, but that he might need Geiger's assistance. Geiger agreed to work with Kulakow on this topic, noting that he has already started performing risk assessments on the Subgroup's data. He analyzed data for Sites F and G, he said, to determine whether site-specific cleanup goals could be generated using the RBCA framework. This approach was not practical for Site F, but it worked quite well for Site G; in fact, Geiger agreed to send Kulakow the spreadsheets that he used for Site G so that these can serve as a template for other Subgroup members. Jackson said that Ross Smart plans to perform the risk analysis for Site A's data. Geiger agreed to call Smart to find out what default RBCA values he is using. Geiger asked whether Smart will also perform analyses for Site B. Jackson was not sure.

The "Cost Estimation" Section

Kulakow said that the annual report will summarize the costs incurred by Subgroup members during the first year of field activity. He asked conference call participants to fill out cost-tracking spreadsheets as soon as they receive revised versions from Geiger. Kulakow said that he must receive all cost information by late January or early February.

NATIONAL INNOVATION AWARD

Sayre said that the RTDF is being considered for an award that recognizes innovative government projects. To be considered for the award, he continued, RTDF leaders had to submit an estimate of the amount of money spent on RTDF activities. Sayre said that he, Rock, and Jackson generated a rough estimate of the amount spent by the TPH in Soil Subgroup. He agreed to send the estimate to ERG so that it can be distributed to the entire Subgroup. Rock said that Subgroup members should feel free to comment on the estimate and to offer input. If the Subgroup members are able to create a more accurate estimate, Rock said, it may be beneficial to list it in the Subgroup's annual report.

NEXT FACE-TO-FACE MEETING

Rock said that a phytoremediation conference is scheduled at the Omni-Parker hotel in Boston, Massachusetts, on May 1-2, 2000. The meeting is being held, Rock said, so that researchers can share information on their work. Topics on the agenda include remediation of metals, remediation of organics, capping, and the fate of trichloroethylene and tetrachloroethylene. Rock agreed to send a preliminary meeting agenda to ERG so that it can be distributed to all Subgroup members.

Rock said that meeting room space has been reserved at the Omni-Parker hotel for May 3, 2000--the day after the phytoremediation conference--so that the Phytoremediation Action Team Subgroups can meet. He said that the Alternative Cover Assessment Program (ACAP) Subgroup will meet for a half day on May 3, and that the TPH in Soil Subgroup can do the same if it desires. Conference call participants said that they are not yet sure whether a meeting will be necessary, but that they would like to tentatively reserve a meeting slot for the morning of May 3, 2000. They spent a few minutes brainstorming on potential meeting agenda items. They suggested lining up a few presentations and then using the remainder of the time to interact with regulators. Some conference call participants recommended having the regulators (e.g., Felix Flechas) give formal presentations. Other participants suggested holding an informal question and answer session. Nadeau said that it could be very beneficial to invite regulators, noting that several RPMs are starting to think about using phytoremediation as a polishing technology. Nadeau said that he is currently working with an RPM on a site in Pennsylvania. The site, which is contaminated with oil, is being treated with a suite of warm-weather grasses. Nadeau said that he may be able to persuade some interested RPMs to attend a TPH in Soil Subgroup meeting on May 3, 2000.

MISCELLANEOUS TOPICS

The following miscellaneous items were discussed during the call:

• Kulakow said that he would like to talk to Nadeau about some of the sites he is working on to determine whether any might be appropriate for inclusion under the Subgroup's field program.

• Rock said that the Interstate Technology Regulatory Cooperation Work Group has created a decision tree for phytoremediation; it can be accessed at http://www.clu-in.org.

• Drake and Nadeau said that it is often very difficult to convince regulators and site managers of the merits of phytoremediation. Many are discouraged by how long the technology takes to meet cleanup goals. To help shorten the timeline for remediation, Nadeau said, he and Jim Brown are experimenting with a phased approach, in which phytoremediation follows a short, but aggressive, bioremediation phase. Drake expressed strong enthusiasm for this approach.

• Drake noted that field activities at Subgroup sites are currently planned to take place over three years. She said that it might be necessary to collect data over five years, noting that the effectiveness of phytoremediation may not be immediately apparent. She suggested that Subgroup members start thinking about extending project time spans.

ACTION ITEMS

• Wolf agreed to send Site J's time zero (T₀) samples to ADL.

• Rock agreed to check on the status of CRADAs for sites H, I, and J.

• Kulakow agreed to update the Subgroup's "Status of Field Sites" worksheet before the next conference call. In the revised version, Kulakow will propose a new way to label sampling events.

• Call participants agreed to forward T₀ data to Kulakow if they have not already done so.

• Kulakow agreed to incorporate additional information about weathering ratios in the Subgroup's annual report.

• Kulakow agreed to include a table that breaks down T₀ data by treatment in the Subgroup's annual report.

• Subgroup members agreed to send Kulakow sentences or brief paragraphs explaining how regulatory approval was obtained at Subgroup field sites.

• Kulakow agreed to incorporate information on the TPHCWG methodology in the Subgroup's annual report. Geiger will provide guidance if Kulakow needs it.

• Geiger said that he is using the TPHCWG methodology to assess Site G's data. He agreed to send Kulakow the results in the near future. Also, he agreed to send Kulakow his spreadsheets so that other Subgroup members can use them as a template.

• Geiger agreed to call Smart to determine what RBCA default values he is using.

• Geiger agreed to modify the Subgroup's cost and accounting spreadsheets. After doing so, he will distribute these to the entire Subgroup. Subgroup members agreed to fill in the spreadsheets and forward them to Kulakow by late January or early February.

• Sayre said that a rough number has been generated to estimate how much the Subgroup has spent. He agreed to send the estimate to ERG so that it can be distributed to the entire Subgroup. Subgroup members should feel free to offer input on the estimate.

• Rock said that a phytoremediation conference will be held in Boston, Massachusetts, in early May 2000. He agreed to send a preliminary meeting agenda to ERG so that it can be distributed to the entire Subgroup.

• Kulakow agreed to talk to Nadeau about including one of his sites in the Subgroup's field program.

• ERG agreed to set up the next conference call for February 17, 2000, between 12:00 and 1:30 EST.