Depositional patterns of iron, manganese, and phosphorus in one central and five northern Wisconsin lakes ranging from oligotrophic to eutrophic, primarily from natural causes, have been investigated.One-meter cores from one or more locations within each lake were analyzed.The historical pattern of iron and manganese deposition is closely related to the pattern of phosphorus deposition in most of the cores. Four of the nine cores show a strong positive correlation coefficient between P and Fe and seven between P and Mn. Manganese has more predictive value than iron for determining the concentration of phosphorus in a given core; however, the iron content appears to be the dominant factor in the phosphorus sorptive and retentive capacity of sediments.

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Field and laboratory studies were conducted on the behavior of Kepone and fifteen other chlorinated hydrocarbon pesticides and PCBs during the dredging of the James River, Virginia near Windmill Point. Over a period of six hours, water samples were collected from an area extending three miles up and downstream from the end of the dredge discharge pipe outfall. Laboratory experiments involved mixing sediment and water samples at a 1:4 ratio for 30 minutes and separation of the aqueous phase by centrifugation (elutriate test). Data on field samples including photocopying, microfilming, and recording, or by any information storage and retrieval system, without permission in writing from the publisher. Downloaded by [University of Cambridge] at 01:38 15 June 2016 262 SALEH, LEE, AND BUTLER showed that the "release" of chlorinated organic residues, including Kepone, was mainly associated with the colloidal and particulate matter. The elutriated test results indicated a slight tendency for release of chlorinated organic residues in the soluble and colloidal fraction. In samples collected from the contaminated Bailey Creek area, higher concentrations of Kepone were detected in the soluble or colloidal fraction than found from sediments collected in the nearby James River. Data on Kepone in water and sediment suggest that the compound exhibits a behavior different from the other common chlorinated organic residues.

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