A GEOCHEMICAL INVESTIGATION OF THE FOREST RIVER ESTUARY AND ITS CONTAMINATION AS A RESULT OF THE CHADWICK MILLS

The Forest River Estuary of Salem Massachusetts is contaminated with lead most likely from the past industrial activities of the Chadwick Mills. Previous studies on the distribution of contaminates focused exclusively on lead.

In this study samples were collected and analyzed using an X-ray fluorescence spectrometer (XRF) to determine concentrations of As, Cd, Cr, Cu, Pb, Hg, Ni, Ag, and Zn, in the sediments of the estuary. Shards of pottery that were produced by the Chadwick Mills were also collected on a beach near the mouth of the river. Samples of the different types of pottery contain lead levels that range from 100ppm to 58,660ppm and mercury levels from 11ppm to 218ppm. Metals that occur above the Effects Range Median (ERM) in the sediment include Pb and, when detectable, Hg. Additionally Cr, Cu, and Ni have values above the Effects Range Low (ERL). Trace metals such as Pb, Hg, Cu, Ni, Zn, and Cr were plotted against Fe. Zn and Cu showed a positive correlation to Fe within the sediments while Pb showed no correlation.

Many of these trace metals have been shown to be harmful to marine biology. To help determine the potential impact of the trace metals on the fauna, mollusk shells are being collected and analyzed on an XRF to track the incorporation of the trace metals into the shells. Additionally a sediment core was taken to determine the vertical mobility of trace metals. Moreover results of this study can be compared to other estuaries in the region to investigate the impact that different industrial activities have on the distribution of trace metals.