FINGERPRINTING AND IDENTIFYING EXTENT OF A HYDROCARBON CONTAMINANT SPILL IN A TIDAL CREEK USING REMOTE SENSING AND GEOCHEMICAL TECHNIQUES

Oil distillates and their constituent petroleum hydrocarbons (PHs) can contaminate large bodies of water to cause ecological damage and pose significant threat to human health. Leaking underground tanks at gasoline stations, accidental spills, surface runoff from parking lots, and improper disposal practices are the leading causes of PH contamination of soils, surface water, and groundwater. Remote detection of such pollution using visible-near infrared and short-wave infrared spectroscopy has gained popularity over the last decade as a useful technique in establishing baselines and monitoring spills. However, actual ground measurements are still required to accurately assess the extent of contamination in the field and to evaluate the veracity of remote sensing data. Recently, using remote sensing techniques, we identified a PH contaminated site in North Charleston, South Carolina. On further investigation, we found that a large quantity of gasoline/kerosene was spilled into the tidal marsh adjoining the Cooper River. Preliminary analysis, using spectroradiometry, of tidal sediment collected in this area produced an anomalous absorption feature at 2300nm indicating the presence of PHs. We also measured the levels of PH levels using a combination of headspace analyses on a gas chromatograph flame ionization detector (GC/FID), but the results were inconclusive due to our inability to quantify the extent and nature of all PH contaminants in the sediments. We are currently extracting PH compounds from these sediments using a combination of head space analysis and microwave-assisted solvent extractions and will analyze the PH compounds on a gas chromatograph mass spectrometer (GC/MS.) This combination will yield both volatile and semi-volatile PH compounds. The PH chromatograms obtained in the GC/MS will be compared with those obtained from extracting pure gasoline/kerosene. The results of this study will be presented at the conference.