USING CHEMICAL AND PHYSICAL MEASUREMENTS IN A STRATIFIED SEDIMENT CORE TO MAKE INFERENCES ABOUT PAST HUMAN ACTIVITY IN THE NEW MEADOWS RIVER AREA, MIDCOAST MAINE

This study builds upon the work started during the summer of 1999 on the New Meadows River. The river is an elongate, rock-bound estuary that separates the towns of Brunswick and West Bath in midcoast Maine. Due to the presence of several current and historical potentially polluting activities in the watershed, this study was undertaken to determine the possibility of using stratified sediment cores to determine the past contamination history of the area. With the advent of industry in Maine, starting with European settlement, it is possible that metals such as copper and lead contaminated the sediment. Change in land-use, fires, and land-based fossil fuel use would add polycyclic aromatic hydrocarbons (PAH) to the sediment. Different sources of PAH have different “fingerprints” and could be studied by chemical analysis. As the river began to service more people, the number of non-point pollution sources would have certainly increased and likely would have affected the total organic carbon of the sediment. With deposition assumed to be ~2mm/year, one meter sediment cores were taken from soft sediment depositional areas on this river to reflect the last 300-500 years of the river. Physical –chemical characteristics of these cores, including total organic carbon and sediment grain size, allow us to quantify deposition over the years. PAH analyses on sediment layers will be done using liquid chromatography, GC-FID, and GC-MS techniques to identify the distributions of PAH analytes that will provide evidence of PAH sources and thus, historical activities.