2006 Annual Report
1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter?
The foundry industry in the United States generates as much as 10 million tons of waste sand annually, with 90% being discarded in municipal and private landfills. The foundries use the sands to produce molds and cores for metal casting; the bulk of the waste foundry sand (WFS) is molding sand. The most commonly used molding material is green sand, which is largely made of finely graded silica sand and lesser quantities of bentonite clay and other carbonaceous additives. In an effort to divert WFSs from landfills, there is interest in beneficially using the sands in value-added agricultural and horticultural products. However, trace metals and organics in WFSs may present a risk to humans if used to grow food crops.
The overall objective of this project is to identify the benefits and risks of using WFSs in agricultural and horticultural applications. Specific goals are to.
1)characterize trace metals and organics in WFSs from foundries throughout the U.S.,.
2)determine if WFSs present a risk to soil microorganisms, earthworms, and plants,.
3)determine if treatment or blending of WFSs with other byproducts such as manures, biosolids or composts will reduce the movement potential of harmful constituents, and.
4)develop beneficial use guidelines for distribution to state regulatory agencies.
2.List by year the currently approved milestones (indicators of research progress)
Months of study from project initiation (project initiated May 2005):
May 2007 National study to characterize trace metals and organics in waste
October 2008 Greenhouse studies to assess the risk of foundry sands to soil
microorganisms, earthworms, and plants.
May 2009 Studies to assess the leaching potential of foundry sand
May 2010 Final evaluation of results and complete beneficial use guidelines.
4a.List the single most significant research accomplishment during FY 2006.
Metal availability data are needed before many states will consider allowing the use of waste foundry sands (WFSs) in manufactured soils and composts. We conducted a 28-day experiment with the earthworm Eisenia fetida and 6 different WFSs to assess the bioavailability of metals in blends containing 10, 30, and 50% WFS. After 28 days, the number of adult earthworms across all treatments and blending ratios was not significantly different from the control, except in blends containing 30% and 50% WFS from a brass foundry. The high earthworm mortality in the brass sand blends correlated well with the high total and diethylenetriamine pentaacetic acid (DTPA)-extractable concentrations of Cu, Pb and Zn. Heavy metal concentrations in the tissues of earthworms from iron, aluminum and steel WFS blends did not exceed those in the control. The Cu and Zn levels in worm tissue from the 10% brass blend were about 10 and 2 times higher than the control, respectively. Based upon our results, the iron, aluminum and steel WFSs tested in this study do not appear to pose a toxicity and metal transfer risk.
4b.List other significant research accomplishment(s), if any.
4c.List significant activities that support special target populations.
see sibling projects.
5.Describe the major accomplishments to date and their predicted or actual impact.
No major accomplishments have been completed so far. However, several significant research experiments have been initiated and completed since the inception of the project. In the next two years the data collected from this project will be used to assist state regulatory agencies in developing beneficial use guidelines for waste foundry sands. Successful beneficial use of foundry sands will help divert millions of tons of waste sand from landfills and potentially save the foundry industry millions of dollars in disposal costs.
6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products?
No science and/or technologies have been transferred during FY 2006.
7.List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below).
The USDA-ARS Foundry Sand Project. U.S. EPA, National Foundry Sand Stakeholder meeting. Philadelphia, PA, December 1, 2005.
The Characterization of Potential Contaminants in Waste Foundry Sands. Wisconsin Workshop on Pulp and Paper Residuals, Foundry Sand and Composts. Sponsored by the Great Lakes Management Byproducts Association, Fond Du Lac, WI, June 20, 2006.
Dungan, R.S., Kukier, U., Lee, B. 2006. Blending foundry sands with soil: effect on dehydrogenase activity. Science of the Total Environment. 357(1-3):221-230.
Dungan, R.S. 2005. Headspace solid-phase microextraction for the determination of benzene, toluene, ethylbenzenes, and xylenes in foundry molding sand. Analytical Letters. 38:2393-2405.
Dungan, R.S., Reeves III, J.B. 2006. Mid-infrared analysis of foundry green sands and chemically bonded cores. Journal of Residuals Science & Technology. 3(1):61-66.
Dungan, R.S., Dees, N.H. 2006. Metals in waste foundry sands: assessment with earthworms. Journal of Residuals Science & Technology. 3:177-184.
De Koff, J.P., Lee, B.D., Dungan, R.S. 2006. Composting waste foundry sand with leaves to amend adverse physical properties [abstract]. World Congress of Soil Science. [CD-ROM] 143-6.