GLEC researchers conducted an integrated sediment quality assessment at a contaminated site that was discharging contaminated ground water to an adjacent wetland and coldwater stream. The work included the performance of rapid bio-assessment protocols with meaningful reference locations. The concentration of various metals in the ground water was compared and correlated with the concentration of metals in stream and wetland sediments. Whole sediment toxicity tests conducted with the wetland sediment indicated that the sediment nearest the contamination source were toxic and that the toxicity diminished downstream until no toxicity was evident. Benthic invertebrate analysis also indicated affected populations in the sediment nearest the source of contamination and benthic diversity and abundance increased downstream. The analysis of whole sediment and sediment porewater for metals indicated that copper was present at concentrations sufficient to cause toxicity in the sediment nearest the source of contamination and also diminished downstream. Other metals were not measured at concentrations sufficient to cause toxicity. Since there was a high correlation of the concentration of copper in groundwater, whole sediment, sediment porewater with sediment toxicity and benthic diversity, copper was determined to be the causative agent.
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