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

February 28, 2002
12:30 p.m.-2:00 p.m.

On February 28, 2002, 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:

Henry Camp, Arthur D. Little Laboratory
Steve Geiger, ThermoRetec, Inc.
Peter Kulakow, Kansas State University
Steve Rock, U.S. Environmental Protection Agency (EPA)
David Tsao, BP America
Duane Wolf, University of Arkansas

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

UPDATE ON SAMPLE ANALYSIS

The TPH in Soil Subgroup has created a field study program to evaluate how effectively plants degrade petroleum hydrocarbons. Samples have been collected from several sites and sent to the Arthur D. Little Laboratory (ADL) for analysis. Henry Camp said that ADL is currently analyzing samples from Sites B, I, and J. Results will be sent to Peter Kulakow as soon as possible.

COMMENTS ON THE ANNUAL REPORT

Kulakow said that EPA representatives submitted comments on the Subgroup's second annual report. The comments focused on the following:

• Surrogate-corrected data. EPA's commenters expressed concern about the Subgroup's decision to present surrogate-corrected data. A preference for non-corrected data was expressed. Kulakow offered to perform analyses with surrogate-corrected and non-corrected data for Site A and to compare the results. (The Subgroup was using the surrogate-corrected data because this helps correct for variabilities in extraction and analytical processes.) Kulakow will communicate with Steve Rock and EPA's commenters to determine the best way to proceed. A decision must be made on how to present the data in the second annual report. For example, is it necessary to analyze the non-corrected data for all of the sites at this point? Or would it be better, in the interest of time, to present the surrogate-corrected data in the second annual report and use the non-corrected data in the third annual report?



• TPH and hopane normalization. EPA's commenters expressed concern about using the hopane normalization process with TPH data; Kulakow will contact them for clarification.

Before presenting the next EPA comment, Kulakow brought up some additional issues related to hopane. He noted that hopane is expressed on an oil weight basis in the second annual report. Results were as expected at some Subgroup sites, he said, but not at all of them. He was unsure how to explain this discrepancy. Camp said that hopane might not be a useful analytical tool at all sites, noting that the strength of this biomarker's signal will vary depending on the type of petroleum product (e.g., crude oil versus refined products) and the degree of weathering the site has experienced. Steve Geiger asked whether other normalization techniques have been developed to address contaminated sites that do not have hopane present in high concentrations. Camp and Kulakow suggested looking at the "early" polycyclic aromatic hydrocarbon (PAH) relative to the site's heaviest, and most recalcitrant, PAH. Camp said that it would be useful to create a decision tree to help researchers determine which analyses to apply to specific sites. Duane Wolf asked whether the hopane signal is strong enough at Site J. Camp said that it is, but that this type of analysis is not necessary at Site J since PAH concentrations have virtually disappeared.

• Chromatograms. EPA's commenters, Kulakow said, asked that labels be added to the major chromatogram peaks. Camp said that this can be done, but asked Kulakow to obtain clarification on what needs to be labeled. Kulakow agreed to do so. In addition, Kulakow said, EPA's commenters asked why the chromatograms were not presented on the same Y axis. Camp said that trends in TPH patterns would not have been visually discernable if this approach had been taken. Kulakow said that he would add some text to explain why different Y axes were used.

Kulakow said that he had one other data-related question: is it acceptable to substitute ADL's "nondetects" with zeros? Rock said that he would find out and report back to Kulakow within a week.

NEXT TPH IN SOIL SUBGROUP MEETING

Rock suggested holding the next TPH in Soil Subgroup meeting in Cincinnati, Ohio, in late August or early September 2002. EPA's Al Venosa and Ann Vega, both of whom can offer insight on data quality issues, will be encouraged to attend. Call participants thought this was an excellent idea. Rock agreed to start making plans for the meeting.

OTHER MEETINGS

Rock presented information about three other meetings:

• March 2002 Association for Environmental Health and Sciences meeting in San Diego, California. Rock noted that some TPH in Soil Subgroup members plan to attend this conference. They may try to meet informally for dinner on March 20, 2002.



• May 2002 meeting in Rome, Italy. Rock said that he plans to provide information about the TPH in Soil Subgroup at a meeting in Rome, Italy, during the third week of May 2002.



• Phytoremediation State of the Science Conference. EPA held a comprehensive phytoremediation conference in May 2000 in Boston, Massachusetts. Rock said that EPA is interested in holding another conference like this in late 2002 or 2003.

NEXT SUBGROUP CONFERENCE CALL

Call participants tentatively set April 10 as the date for the next Subgroup conference call. Rock will contact Lucinda Jackson, Venosa, and Vega to find out whether they can participate. If so, he will ask ERG to set up the call. If not, he will communicate with Subgroup members to identify an alternative date.

ACTION ITEMS

• Kulakow will send conference call participants the comments that EPA submitted on the Subgroup's second annual report.



• Kulakow will set up a call between himself, Camp, Venosa, and Vega. The call will be held to obtain clarification on comments offered on the Subgroup's annual report.



• Rock will start making plans for the next TPH in Soil Subgroup meeting. (It has tentatively been scheduled for late August/early September 2002, in Cincinnati, Ohio.)



• Rock will find out whether Jackson, Venosa, and Vega are available for an April 10, 2002, conference call. He will report back to Subgroup members.



• Rock said that he will find out what EPA's policy is on substituting "nondetects" with zeros. He will report back to Kulakow within a week.