Mined Land Reclamation Using Polluted Urban Navigable Waterway Sediments: II. Organics1
- A. van Luik2
Maintenance dredging potentially produces an estimated 15 000 m3 of sedimentary material from the Calumet-Sag Channel (Cal-Sag) annually. To determine the suitability of this dredged material for use in the reclamation of abandoned mined lands, 10 sediment samples were taken at 2.4-km intervals along the length of the Cal-Sag using a gravity corer. Sediment cores (107 to 173 cm in length) were subdivided to represent 40- to 50-cm depth increments, and composite samples were taken along the length of each subsample. Organic pollutant concentrations as well as silt and clay contents were determined. No significant correlations existed between each organic pollutant concentration and sediment sample depths, locations, or sediment silt or clay content. This result suggested that the mean and the mean plus twice the standard deviation offered good approximations of the expected mean value and the expected (95%) maximum value for these pollutants in Cal-Sag dredged material (volatile solids: 9.85 and 13.1 mg/kg; oil and grease: 11.9 and 22.7 g/kg; total phenols: < 2.4 and < 4.8 mg/kg; and total polychlorinated biphenyls (PCB's): 7.0 and 17 mg/kg). Polycyclic aromatic hydrocarbon (PAH) levels were determined for nine selected Cal-Sag sediment samples. Measured parent PAH compound levels (46 compounds) exceeded 80 mg/kg in only one sample. Alkyl-substituted PAH compound concentrations were measured for three parent compounds in three sediment samples and found to be highly variable in concentration (∼ 1 – ∼ 500 mg/kg).Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
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