Effects of Contaminants in Dredge Material from the Lower Savannah River

Abstract. Contaminants entering aquatic systems from agricultural, industrial, and municipal activities are generally sequestered in bottom sediments. The environmental significance of contaminants associated with sediments dredged from Savannah Harbor, Georgia, USA, are unknown. To evaluate potential effects of contaminants in river sediments and sediments dredged and stored in upland disposal areas on fish and wildlife species, solid-phase sediment and sediment pore water from Front River, Back River, an unnamed Tidal Creek on Back River, and Middle River of the distributary system of the lower Savannah River were tested for toxicity using the freshwater amphipod Hyalella azteca. In addition, bioaccumulation of metals from sediments collected from two dredge-disposal areas was determined using the freshwater oligochaete Lumbriculus variegatus. Livers from green-winged teals (Anas crecca) and lesser yellowlegs (Tringa flavipes) foraging in the dredge-spoil areas and raccoons (Procyon lotor) from the dredge-disposal/river area and an upland site were collected for metal analyses. Survival of H. azteca was not reduced in solid-phase sediment exposures, but was reduced in pore water from several locations receiving drainage from dredge-disposal areas. Basic water chemistry (ammonia, alkalinity, salinity) was responsible for the reduced survival at several sites, but PAHs, metals, and other unidentified factors were responsible at other sites. Metal residues in sediments from the Tidal Creek and Middle River reflected drainage or seepage from adjacent dredge-disposal areas, which could potentially reduce habitat quality in these areas. Trace metals increased in L. variegatus exposed in the laboratory to dredge-disposal sediments; As, Cu, Hg, Se, and Zn bioaccumulated to concentrations higher than those in the sediments. Certain metals (Cd, Hg, Mo, Se) were higher in livers of birds and raccoons than those in dredge-spoil sediments suggesting bioavailability. Cadmium, Cr, Hg, Pb, and Se in livers from raccoons collected near the river and dredge-disposal areas were significantly higher than those of raccoons from the upland control site. Evidence of bioaccumulation from laboratory and field evaluations and concentrations in sediments from dredge-disposal areas and river channels demonstrated that some metals in the dredge-disposal areas are mobile and biologically available. Drainage from dredge-disposal areas may be impacting habitat quality in the river, and fish and wildlife that feed and nest in the disposal areas on the lower Savannah River may be at risk from metal contamination.

[1]  Reed C. Harris,et al.  Increases in Fluxes of Greenhouse Gases and Methyl Mercury following Flooding of an Experimental Reservoir , 1997 .

[2]  P. Winger,et al.  A vacuum-operated pore-water extractor for estuarine and freshwater sediments , 1991 .

[3]  William Post,et al.  FRESHWATER WETLANDS, RAINFALL, AND THE BREEDING ECOLOGY OF WHITE IBISES IN COASTAL SOUTH CAROLINA , 1990 .

[4]  T. Murphy,et al.  Diffusion method for the determination of acid-volatile sulfides (AVS) in sediment , 1994 .

[5]  D. Spry,et al.  Toxicological significance of mercury in freshwater fish , 1996 .

[6]  L. Harris,et al.  Everglades: The Ecosystem and its Restoration. , 1995 .

[7]  P. Winger,et al.  Environmental contaminant concentrations in biota from the lower Savannah River, Georgia and South Carolina , 1990, Archives of environmental contamination and toxicology.

[8]  A. Scheuhammer.  Effects of acidification on the availability of toxic metals and calcium to wild birds and mammals. , 1991, Environmental pollution.

[9]  G. L. Storm,et al.  Ecotoxicological damage from zinc smelting at Palmerton, Pennsylvania , 1995 .

[10]  W. P. Miller,et al.  A micro‐pipette method for soil mechanical analysis , 1987 .

[11]  J. Barr.  Population dynamics of the Common Loon (Gavia immer) associated with mercury-contaminated waters in northwestern Ontario , 1986 .

[12]  G. Ankley,et al.  Acid volatile sulfide predicts the acute toxicity of cadmium and nickel in sediments , 1992 .

[13]  V. Hodge,et al.  Pollution history of the Savannah River Estuary , 1979 .

[14]  Gerald T. Ankley,et al.  Methods for measuring the toxicity and bioaccumulation of sediment-associated contaminants with freshwater invertebrates , 1994 .

[15]  J. Birkner.  Selenium in Aquatic Organisms from Seleniferous Habitats. , 1978 .

[16]  G. Bennett.  Arsenic in the environment — Part II: Human health and ecosystem effects , 1996 .

[17]  Sediment toxicity in Savannah Harbor , 1995 .

[18]  R. Hecky,et al.  Increases in Fish Mercury Levels in Lakes Flooded by the Churchill River Diversion, Northern Manitoba , 1984 .

[19]  B. E. Davies,et al.  Loss-on-Ignition as an Estimate of Soil Organic Matter1 , 1974 .

[20]  L. G. Morgan,et al.  The Potential for Biological Effects of Sediments-Sorbed Contaminants Tested in the National Status and Trends Program , 1990 .

[21]  F. J. Dwyer,et al.  A water-renewal system that accurately delivers small volumes of water to exposure chambers , 1994 .

[22]  U. S. N. B. Suraey,et al.  11 A REVIEW OF ARSENIC HAZARDS TO PLANTS AND ANIMALS WITH EMPHASIS ON FISHERY AND WILDLIFE RESOURCES , 1998 .

[23]  M. Mac,et al.  Accumulation by fish of contaminants released from dredged sediments , 1982 .

[24]  R. Furness,et al.  Mercury and selenium interaction: a review. , 1991, Ecotoxicology and environmental safety.

[25]  P. Winger,et al.  Effects of salinity on striped bass eggs and larvae from the Savannah River, Georgia , 1994 .

[26]  Effects of Saltwater Intrusion and Flow Diversion on Reproductive Success of Striped Bass in the Savannah River Estuary , 1994 .

[27]  D. Mount,et al.  Application of toxicity‐based fractionation techniques and structure‐activity relationship models for the identification of phototoxic polycyclic aromatic hydrocarbons in sediment pore water , 1998 .

[28]  P. Monson,et al.  Influence of ultraviolet light on the toxicity of sediments contaminated with polycyclic aromatic hydrocarbons , 1994 .

[29]  Ralph Mitchell,et al.  Sulfate stimulation of mercury methylation in freshwater sediments , 1992 .

[30]  Fred D. Calder,et al.  Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuarine sediments , 1995 .