LEAD STUDY OF THE FOREST RIVER ESTUARY, SALEM, MASSACHUSETTS

The Forest River Estuary in Salem, Massachusetts, has experienced lead (Pb) contamination from former industrial activities. This study was performed to determine the distribution of Pb in the estuary's surface sediment. Twelve surface sediment samples (0-2cm) were taken from the mouth of the river to approximately one half mile up the estuary of Forest River. The sample locations were distributed in such a way as to determine how far the pollutant had spread. The sediment samples were digested using the partial digestion Environmental Protection Agency (EPA) Method 3050B. Pb concentrations were determined using a Perkin Elmer AAnalyst 300 based on a calibration curve that was produced by certified lead standards bracketing the concentrations analyzed. The concentrations were reported as parts per million by mass. Long and others (1995) used toxicity tests to establish two critical contamination levels for different pollutants in marine environments: Effects Range Low (ERL) and Effects Range Median (ERM). The Effects Ranges allow scientists to group their findings into three levels based on potential ecological impacts. The findings in this study spread between no detection of Pb to above the ERM. Of the twelve samples seven are between no detection of Pb to below the ERL. However there are five samples above the ERL along with one that is above the ERM. The findings of this research discovered the sample above the ERM was closest to the mouth of the river into the bay. The other areas of interest can be found at the mouth of the river and on depositional banks of the meandering river. The second highest reading was discovered in a former meander, which is currently a small basin connected to the main channel. Perhaps the basin acted as a sediment trap for contaminants flowing upriver on the flood tides. The levels of Pb discovered in the surface sediment of Forest River Estuary are high enough that they can be potentially dangerous to the local marine life. Future studies should be conducted to fully resolve the distribution of Pb in this otherwise healthy estuary.