PERIODIC PROCESSES FOR IN-SITU AND ON-SITE BIOREMEDIATION OF LEACHATES AND SOILS

Investigators at the University of Notre Dame's Center for Bioengineer ing and Pollution Control have conducted research and development stud ies since 1980 in the broad area of hazardous waste management. These efforts have been primarily directed at the use of periodic processes. Many of the findings have been applied to the construction and operat ion of full scale bioreclamation facilities. Early research and develo pment activities were directed at the suspended growth, Sequencing Bat ch Reactor (SBR). The SBR is an activated sludge-like, periodic proces s that has been used effectively for the treatment of both domestic an d industrial wastewaters (Irvine and Busch, 1979; and Irvine and Ketch um, 1989). Due to the time-oriented nature of the SBR, simple operatio nal modifications have allowed for nutrient removal (Alleman and Irvin e, 1980a; Alleman and Irvine, 1980b; Ketchum et. al., 1987; Irvine et. al., 1979; Manning and Irvine, 1985; and Palis and Irvine, 1985) and the control of bulking sludge (Brenner et. al., 1992; Chiesa and Irvin e, 1985; Chiesa et. al., 1985; and Dennis and Irvine, 1979). The SBR h as been shown to be a cost effective and energy efficient means of rem oving hazardous organic compounds found in industrial wastes and leach ates from landfills (Brenner et. al., 1992; Herzbrun et. al., 1985; Ir vine et. al., 1984; Irvine and Wilderer, 1988; Smith and Wilderer, 198 7; and; Ying et. al., 1987). The Soil Slurry-Sequencing Batch Reactor (SS-SBR) described by Irvine et. al. (1993) and the Sequencing Batch B iofilm Reactor (SBBR), a fixed film periodic system that can be used i n conjunction with granular activated carbon (Chozick and Irvine, 1991 ), were developed in the late 1980's and early 1990's. Recent efforts have been directed at periodically operated in situ bioremediation sys tems. This paper provides a brief overview of how such systems can be used to bioremediate contaminated leachates and soils.