Water Resources Research Act Program

Details for Project ID 2004MO34B

The Leaching Behavior of Arsenic and Selenium from Fly Ash and Their Potential Impact on Water Quality

Institute: Missouri
Year Established: 2004 Start Date: 2004-03-01 End Date: 2005-02-28
Total Federal Funds: $22,000 Total Non-Federal Funds: $45,152

Principal Investigators: Jianmin Wang, Joel Burken

Abstract: The Leaching Behavior of Arsenic and Selenium from Fly Ash and Their Potential Impact on Water Quality Jianmin Wang and Joel Burken The EPA has recently reduced the Maximum Contaminant Level (MCL) for arsenic in drinking water from 50 ppb to 10 ppb, and all drinking water systems must comply with this new standard by January 2006. Fly ash contains many heavy metals including arsenic, and is probably one of the largest arsenic sources. Therefore, understanding the leaching behavior of arsenic from fly ash is significant in predicting the arsenic impact on the drinking water quality and in developing innovative technologies to control arsenic leaching. Selenium, another anionic heavy metal in fly ash, is also greatly concerned by EPA and utilities. The overall objectives of this project are (1) to investigate the leaching behavior of arsenic and selenium from fly ash under different environmental conditions; (2) to understand the arsenic and selenium leaching behavior through the determination of reaction constants between different arsenic and selenium species and fly ash; and (3) to develop models to describe arsenic and selenium leaching from fly ash. The project is divided into six tasks: (1) sample identification and collection; (2) basic leachabilty study using batch system under different pH conditions; (3) sample preparation and characterization; (4) interactions between different arsenic and selenium species and fly ash; (5) modeling arsenic and selenium interactions with fly ash; and (6) technology transfer through publications, presentations, and reports. Batch systems will be employed for the experiment. Five ash samples from coal power plants in Missouri and the nation will be used to conduct the general leachabiltiy study. Among these 5 samples, 2 of them will be collected for detailed study. Models will be developed to describe the interactions between different arsenic and selenium species and fly ash. Upon completion of this research, one should be able to understand the fundamental information related to the arsenic and selenium leaching from fly ash, and predict the leaching process in batch systems. This project will provide support for one Ph.D. student in Civil, Architectural and Environmental Engineering at UMR for one year. In addition, the PIs plan to involve one undergraduate student in the research through the Opportunities for Undergraduate Research Experiences (OURE) program. This NSF program provides additional funding ($1000) to fund an undergraduate student to be involved in the research, performing research with the graduate student and PIs. This experience will expose the undergraduate student to the research process (hypothesis formation and testing) and increase the likelihood for the student to pursue graduate studies. Through this project, fundamental data will be collected and these data will be used to support future proposals for the more comprehensive research. The potential funding sources include DOE, EPA, and EPRI.