ABSTRACT
In recent years, improper disposal of various waste materials has posed serious threats to surface and groundwater supplies and developed into a global scale soil and water pollution problem [1]. Heavy metals account for much of the contamination found at hazardous waste sites in the United States, and have been detected in the soil and groundwater at approximately 65% of the U.S. Environmental Protection Agency Superfund sites [2]. Dramatic increases in land application of agricultural and municipal biosolids have accentuated the problem. In spite of their beneficial contributions as nutrient sources and soil conditioners, these amendments, if not monitored, pose a considerable environmental risk because of their high heavy-metal concentrations [3].
