Are toxic contaminants accumulating in Massachusetts coastal sediments following startup of the Massachusetts Bay outfall: a comprehensive comparison of baseline and post-diversion periods.
The Massachusetts Water Resources Authority (MWRA) conducts monitoring to address concerns related to the 2000 diversion of secondarily treated effluent discharge into Massachusetts Bay. Baseline data (1992-2000) showed multiple regions defined by physical and chemical composition. Near the Massachusetts Bay outfall, there is a series of heterogeneous sediments in relatively close proximity to the primary historic source of contaminants (Boston Harbor). Farfield sediments exhibited greater compositional definition from one another, which was attributed to the greater spatial separation of the sampling locations. Factors that influence contaminant variability include local and distributed sources, and are primarily related to gradients in depositional environments. Post-diversion sediment data suggest that 4 years of treated effluent discharge has not increased contaminant concentrations to the bay system. However, abundance of the sewage tracer, Clostridium perfringens, has increased variably in sediments located within 2 km of the outfall, providing a distinct effluent signal near the outfall.
Dahlen
Deirdre
D
Battelle Memorial Institute, 397 Washington Street, Duxbury, MA 02332, USA. dahlend@battelle.org
Hunt
Carlton
C
Emsbo-Mattingly
Stephen
S
Keay
Kenneth
K
D001554:Benzene / Q000032:analysis; D002244:Carbon / Q000032:analysis; D003016:Clostridium perfringens / Q000302:isolation & purification; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D004785:Environmental Pollutants / Q000032:analysis*; D019015:Geologic Sediments / Q000032:analysis*; D008404:Massachusetts; D019216:Metals, Heavy / Q000032:analysis; D010316:Particle Size; D010573:Pesticide Residues / Q000032:analysis; D011078:Polychlorinated Biphenyls / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D014865:Waste Disposal, Fluid / Q000379:methods*
D004785:Environmental Pollutants; D019216:Metals, Heavy; D010573:Pesticide Residues; D011084:Polycyclic Aromatic Hydrocarbons; D002244:Carbon; D011078:Polychlorinated Biphenyls; D001554:Benzene