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

September 20, 1999
3:30 p.m.-4:30 p.m.

On Monday, September 20, 1999, 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 Life Sciences (Action Team Co-Chair)
James Ryan, U.S. Environmental Protection Agency (EPA) (Action Team Co-Chair)
Judith Hallfrisch, United States Department of Agriculture (USDA)
Sally Brown, University of Washington
David Mosby, Missouri Department of Natural Resources

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

ACTIVITIES RELATED TO THE JOPLIN, MISSOURI, SITE

The conference call participants opened the call by talking about the data that have been collected from the Joplin site. Bill Berti said that the data have been generated using in vitro soil analyses, plant studies, animal dosing studies, and soil chemistry research.

In Vitro Soil Analyses

Sally Brown said that in vitro analyses were performed on soil samples that were collected from the United States Department of Agriculture's (USDA's) plots in September 1997. The analyses, performed using glycine and a pH of 2.2, revealed a significant reduction in lead bioavailability in several soils that have been amended in the field. Berti asked Brown whether she plans to perform in vitro analyses on soil samples that were collected in September 1998. Some analyses have already been conducted on these samples, Brown said, but at a pH lower than 2.2. She said that she wants to analyze the samples using the higher pH values, but that her laboratory is not set up to perform these analyses. She did say, however, that she asked John Drexler for the plans that outline the in vitro test set-up. Berti said that he would mail a copy of these plans to Brown.

Berti said that Action Team members plan to collect soil and plant samples from the Joplin site in October 1999. The soil samples will be analyzed with in vitro tests. Conference call participants made different recommendations for the pH level that should be used. Brown recommended performing the analyses at a pH of 2.2, reminding participants that this pH was used to analyze the September 1997 samples. Berti suggested using a pH of 2.3, noting that Mike Ruby has obtained good results using this level. Berti asked conference call participants if they had reviewed Ruby's data. Several participants said that they could not download Ruby's file. Berti agreed to distribute the data to Brown, James Ryan, and David Mosby.

Plant Studies

Brown said that she is analyzing plant data and working on a manuscript. The manuscript will discuss changes in lead bioavailability in plants over time, and correlations that exist between plant and in vitro data. Ryan asked if there is reason to suspect that such a correlation will exist. Strong correlation has not been observed to date, Brown admitted, but more analyses are required before the relationship between the two forms of data can be ascertained.

Animal Dosing Studies

Mosby said that a swine dosing study will be performed soon. A study design has been proposed, he said, and three soil samples have been recommended for dosing: (1) untreated control, (2) lead acetate, and (3) 1% phosphorus (P). The 1% P treatment has been selected for the study, Mosby said, because this sample has been dosed to the swine during two previous studies. These other studies were conducted 3 months and 18 months after the soils at Joplin were amended. Dosing the sample again, Mosby pointed out, will provide investigators with a data point for the 30-month mark. Mosby said that EPA's Mark Doolan thinks that collecting several data points over time for the same sample will help address one of the community's questions. That is, how will amended soils change over time? Brown asked whether this question could be addressed using in vitro studies rather than animal dosing studies. Mosby said that this might be possible and that he and Doolan would consider evaluating something other than the 1% P treatment if the Action Team had other recommendations. He did say, however, that the treated sample used in the dosing study must be a plausible remedial treatment. That means, he explained, that treatments with very high phosphorus levels will not be considered, because it is unlikely that these could be applied to people's yards. Brown suggested using the 2.5% iron (Fe)-0.32% P treatment, noting that this treatment has been dosed in rats but not in swine. She said that it might be useful to collect data for this treatment because it will help broaden the Action Team's data set. Mosby expressed interest in this treatment, but voiced concern about the fact that iron interactions in soil are not well understood. Mosby suggested talking offline with Brown and Doolan to discuss which treatment to use.

Judith Hallfrisch said that USDA plans to initiate three rat studies in the near future. All three of the studies will be described in a proposal that Hallfrisch plans to complete by September 23, 1999. Two of the studies, she said, will focus on pure lead minerals and will not use field samples from Joplin. Carbonate and pyromorphite will be the focus of the first study and sulfide and sulfate will be the focus of the second. Some of the samples will have hydroxy appetite, Hallfrisch said, but others will not. Hallfrisch said that the third study will be designed to evaluate field samples from the Joplin site. Ryan suggested analyzing three samples in the third study: (1) an unamended control, (2) a control sample treated with hydroxy appetite, and (3) a treated sample that has been amended in the field. He also recommended using a protocol similar to the one that USDA used in their previous rat dosing study. Ryan expressed enthusiasm for USDA's rat studies, noting that these will help investigators determine whether amended soils react in the field or in the digestive systems of animals. (USDA will investigate whether reactions occur under extreme conditions inside animals.) Mosby said that some data, collected with SEM and XRD, suggest that the reaction occurs in the field. Ryan was aware of this, but noted that the data are limited. He said that he wants to know (1) how long it takes for formation to occur and (2) whether the compounds detected in the animals are a result of pyromorphite addition or formation.

Ryan pointed out that only a few samples from Joplin have been dosed to both rats and pigs. More data points are needed for the same samples, he said, so that investigators can determine if there is correlation between the swine and rat models. Conference call participants agreed with him, stressing the importance of using the same samples for Mosby's upcoming swine test and Hallfrisch's field dosing rat test. Mosby agreed to collect the samples for the animal dosing studies and to make sure that enough material is collected for his and Hallfrisch's studies. Hallfrisch asked whether samples can be stored for long periods before initiating a dosing study. Ryan said that the Action Team discussed this issue before and decided that samples should not be stored for long durations. (He admitted that there are no strong data to support this decision, but said that there are also no data to refute it.) Given the Action Team's stance, Mosby and Hallfrisch discussed ways to coordinate the timing of their animal dosing studies. Hallfrisch said that she was originally planning to conduct USDA's field dosing study after the first of the year. Mosby said that the swine study must be performed before then, because supporting grant monies will terminate soon. Hallfrisch agreed, therefore, to conduct USDA's field dosing study before USDA's other two rat studies. Mosby said that he will contact Stan Casteel to identify an exact date for the swine dosing study and that he will forward this information to Hallfrisch. After a date for the studies is selected, Mosby said, he will make plans to collect samples and to have them split by John Yang. (Conference call participants agreed that the samples for the animal studies do not have to be collected in October 1999, the time when other Action Team members plan to collect samples.)

Soil Chemistry Research

Mosby provided a brief update of Yang's activities, noting that Yang is heading much of the soil chemistry research that is being performed for the Joplin site. Mosby said that Yang is working on an article; the first draft has been reviewed by Casteel.

Reports

Mosby said that he plans to complete his Master's thesis in the near future. In addition, he said, a broader report will probably be completed in October or November. During the last conference call, Brown, Chaney, and Ruby agreed to send Mosby information for inclusion in the second report. Mosby said that he has definitely received materials from Brown and that he thinks he has received information from Chaney and Ruby as well. He agreed to double-check to make sure. One piece of information that he needs, Mosby said, is a detailed description of Joplin's iron-rich treatments. Berti agreed to send Mosby some papers that have been written on this topic.

ACTIVITIES RELATED TO BIOSOLIDS PROJECTS

Berti asked Brown if a biosolids project will be initiated in Jasper County, Missouri. Brown said that it will, but that the project location and initiation date have not been established. Funding for the project has been identified, she said, although the majority of these funds may not be available until next year. Some end-of-the-year funds may be directed to Doolan, however, and used to transport and stockpile materials in treatment areas. Brown said that Doolan and John Dunn would like to perform the project along the outskirts of Joplin, Missouri. A site near Webb City has been identified as one possibility. Brown recommended calling Doolan or Dunn for an update on the status of the Jasper County biosolids project.

Brown described another biosolids project in Missouri. This project, which is being conducted at the Doe Run Company, has already been initiated and materials have been applied to the ground.

Brown also provided an update on the Leadville, Colorado, biosolids project. Small and large plots have been established at this site, she said, with the former planted in July and showing good growth. The larger plots were planted later in the summer, at a time of little rainfall. These plots have been irrigated, Brown said, and some growth has been observed. Brown talked about the pH levels in the larger plots, noting that an agricultural grade of limestone has been added to the site. She said that spot checks indicate that pH levels range from 6.2 to 6.8. These values concern her, she said, particularly in light of what occurred at the biosolids project in Katowicte, Poland. At this site, Brown said, investigators applied limestone and found that their materials did not react enough before becoming coated with iron. Brown said that the project at Leadville may not be performing as expected because the particle size of the material is too small.

MISCELLANEOUS

Conference call members briefly discussed the difference between lead acetate and lead acetate trihydrite. It was agreed that the compounds probably have different solubilities. Mosby said that he will contact Casteel to find out which form of the compound he is using.

Mosby asked for a copy of Steve Germani's isocontour map of lead concentrations. Berti agreed to send this to Mosby. Berti said that he will also send Mosby and Brown a copy of Germani's 1998 data.

Mosby said that two different lead concentrations have been cited for the 1% Fe-1% P treatment plot. He said that one of the values came from Casteel's study, but that he did not know the source of the other value (i.e., 3,087 ppm). Berti said that the value may have been generated using XRF. Mosby agreed to look again for the source of the data. Expanding on this topic of discussion, Ryan reminded conference call participants of the importance of knowing whether a concentration is reported on a whole soil basis or a less-than-fraction basis.

During the last conference all, Mosby agreed to ask Casteel to provide input on Ruby's in vivo study. Mosby said that this action item has been completed.

NEXT CONFERENCE CALL

The next conference call has been set for October 7, 1999, from 3:30 p.m. to 4:30 p.m. EDT.

ACTION ITEMS

• Action Team members agreed to meet in Joplin, Missouri, to collect soil and plant samples.

• Brown said that she needs instructions on setting up in vitro tests. Berti said that he has a copy of John Drexler's plans and that he will send these to Brown.

• Berti agreed to distribute Mike Ruby's in vitro data to Brown, Ryan, and Mosby.

• Mosby suggested talking offline with Brown and Doolan to discuss which treatment to use during the swine dosing study.

• Mosby agreed to contact Casteel to determine when the swine study will be performed. After identifying a date, Mosby will call Hallfrisch to coordinate the animal dosing studies and to choose a date to collect samples from Joplin.

• Berti agreed to send Mosby a description of the iron-rich treatments that were used at Joplin.

• Brown recommended calling Doolan or John Dunn for an update on the Jasper County biosolids project.

• Brown agreed to send Ryan a bucket of sieved soil.

• Mosby said that he will contact Casteel to find out whether he is using lead acetate or lead acetate trihydrite.

• Berti agreed to send an isocontour map of lead concentrations to Mosby.

• Berti agreed to send a copy of Steve Germani's 1998 data to Mosby and Brown.

• Mosby noted that two different lead concentrations have been cited for the 1% Fe-1% P treatment plot. He agreed to find the sources of these numbers.

• ERG will set up the next conference call for October 7, 1999, from 3:30 p.m. to 4:30 p.m EDT.