SUMMARY OF THE REMEDIATION TECHNOLOGIES DEVELOPMENT FORUM
IN-PLACE INACTIVATION AND NATURAL ECOLOGICAL RESTORATION TECHNOLOGIES
SOIL-METALS ACTION TEAM
CONFERENCE CALL

September 25, 2000
4:00 p.m. - 5:00 p.m.

On Monday, September 25, 2000, the following members of the In-Place Inactivation and Natural Ecological Restoration Technologies (IINERT) Soil-Metals Action Team met in a conference call:

Bill Berti, DuPont Central Research and Development (Action Team Co-Chair)
James Ryan, U.S. Environmental Protection Agency (Action Team Co-Chair)
Sally Brown, University of Washington
Rufus Chaney, U.S. Department of Agriculture
Andrew Green, International Lead Zinc Research Organization
Gary Pierzynski, Kansas State University
Mike Ruby, Exponent Environmental Group
Christine Hartnett of Eastern Research Group, Inc., was also present.

THE JOPLIN SITE

Prior to the conference call, Gary Pierzynski circulated a proposal that describes a field project he wants to perform at the Joplin site. This project would examine whether lead bioavailability is reduced when contaminated soils are amended with manganese oxide. Pierzynski’s proposal recommends including nine treatments in the project.

Call participants said that Pierzynski should be allowed to go forth with his proposed project. Rufus Chaney advised formalizing this approval, noting that this could be accomplished by having Bill Berti and Jim Ryan (the IINERT Action Team co-chairs) acknowledge the project in writing. Although call participants expressed enthusiasm for Pierzynski’s project, they did advise him to think about the following before proceeding:

Could animal dosing studies be included in the project?

Call participants noted that bioavailability can be measured using a variety of methods. From a regulatory standpoint, using animal dosing studies is one of the most acceptable techniques. Berti asked Pierzynski whether he will include animal dosing studies in his project. Pierzynski could not guarantee that he would: he is unsure whether there will be sufficient funding for such studies. If possible, Pierzynski will include animal dosing tests. He asked call participants to comment on which animal model they prefer. Ryan said that the swine model is considered the "gold standard." Mike Ruby concurred, noting that the swine model has achieved this status because it has been tested more extensively than other animal models. This does not mean, however, that the swine model is better than other models in an absolute sense.

Is it necessary to include all of the treatments?

Call participants asked whether it is necessary to include all of the treatments that are outlined in Pierzynski’s proposal. The nine treatments can be split into two categories:

• Treatments that do not contain manganese oxide. Pierzynski said that it is important to include treatments that do not have manganese oxide. Without them, it would be impossible to determine the effect that manganese oxide has on amended soils. Chaney agreed with Pierzynski’s point, but said that some of the proposed treatments, such as the control, the triple super phosphate, and the rock phosphate, have already been tested at the Joplin site. Chaney questioned whether it is necessary to re-test these treatments, noting that Pierzynski could simply use data that have already been collected by other researchers. Pierzynski said that he had considered doing so, but feared that he would be criticized for making comparisons between treatments that were installed at different times. Ryan thought Pierzynski’s point was excellent.
  
  
• Treatments that do contain manganese oxide. Pierzynski said that he is not sure exactly how many types of manganese oxide amendment he will test at the Joplin site, noting that he plans to examine a variety of manganese oxides in the laboratory before making a final decision. Call participants said that synthesized cryptomelane is an effective absorber and probably worth testing in the field. Chaney and Ryan did not express the same level of optimism about pyrolusite, a manganese dioxide. Ryan offered to talk to Pierzynski about different manganese sources offline.

Are lead concentrations high enough in the proposed study area?

Sally Brown warned Pierzynski that lead concentrations may not be very high in the proposed study area. Pierzynski said that he plans to collect samples from the site in fall 2000 to determine the exact concentrations. Chaney said that it is preferable to establish plots in areas that have at least 3,000 parts per million (ppm) of lead. The protocol for the swine dosing study lists this concentration as the minimum required. Ryan advised Pierzynski not to lose hope if lead concentrations in the study area do not meet the 3,000 ppm mark. If this is the case, Ryan said, Pierzynski should talk to the University of Missouri’s Stan Casteel to find out if exceptions to the 3,000 ppm minimum can be made.

THE ACTION TEAM’S SYMPOSIUM

The IINERT Action Team plans to hold a symposium at the 2001 American Society of Agronomy (ASA) conference. Berti and Ryan have drafted an outline for the symposium. The outline proposes grouping 14 talks into three categories: (1) introduction and background, (2) Joplin field research, and (3) conclusions and paths forward.

Berti and Ryan said that they are eager to obtain feedback on the outline. Specifically, Ryan wanted to know whether call participants think the symposium’s scope should be limited to the Joplin site or broadened to include what has been learned about bioavailability and ecotoxicity at other sites as well. Pierzynski said that ASA would not object to the Action Team expanding its focus. Ryan asked for call participants’ initial reactions to the suggestion of expanding the symposium’s focus. Chaney expressed enthusiasm for the idea, but Ruby, Green, and Brown had some reservations. Nevertheless, call participants brainstormed about potential topics to include if the focus is expanded. The following were listed: (1) bird studies performed in Coeur d’Alene, (2) urban soil remediation tests performed in Baltimore, (3) Mark Springer’s work on ecotoxicity, (4) Mark Doolan’s work on compost treatments, and (5) Dan Audet’s work on ecological modeling.

Ryan and Berti agreed that there should be another conference call, in which the Action Team will talk more about which topics to include in the symposium, and which format (e.g., formal presentations plus poster sessions) to use. Berti said that a call will be set up in October 2000.

Berti and Ryan said that they would like to finalize plans for the symposium soon. They hope to solidify the Action Team’s plans on the afternoon of November 5, 2000, during a small informal Action Team meeting. (Berti noted that several Action Team members plan to attend ASA’s November 2000 meeting that is taking place in Minneapolis, Minnesota. An informal Action Team meeting will be held before the ASA conference starts.)

MISCELLANEOUS TOPICS

Brown noted that many policy makers have reservations about in situ treatment approaches. Her comment sparked a discussion on changing paradigms in soil treatment approaches. Ruby said that more people are starting to realize that excavation is not the only way to address contaminated soils. He said that it is not practical to excavate all soils that have lead concentrations in excess of 400 ppm. Ryan agreed, noting that risk should be assessed on a site-by-site basis. At some sites, he said, 400 ppm might pose significant risk, but at others, the same concentration does not pose a hazard.