A concern of land farm operators is loss of oil disposal capacity because of residual hydrocarbon buildup. To determine if phytoremediation could expand the capacity of landfarms, microcosms of alfalfa sprouts were tested for their ability to enhance the remediation of soil contaminated with used motor oil as part of a high school chemistry enrichment project. Results indicated that after two weeks of alfalfa growth on 1% oil-contaminated soil, the oil content was reduced by approximately 50% compared to the control, based on gas chromatography of solvent extractions. The following year a field trial was carried out at an industrial landfarm in two fields where the oil and grease concentrations were too high to permit further application of sludge. Two fields, A and B, were planted with alfalfa and sampled periodically over a three-month period. The initial oil and grease content of the fields was approximately 6.5%. This percentage was reduced during the sampling period by 39% and 33% for Field A and B, respectively. The reduction in oil and grease was greater than the amount of hydrocarbon applied during the preceding season and was enough to allow application of additional sludge within the 2000 season.
展开▼
