Management, Partnerships, Monitoring, and Further Reading

Implications for Management

Understanding the long-term fate of sediments and associated contaminants has influenced management decisions and guided long-term monitoring of Massachu- setts and Cape Cod Bays. For example:

Detailed geologic maps were used in selecting the location of the future outfall. The maps identified areas of the sea floor used for fishing and regions where boulders on the sea floor would make construction of the diffuser risers difficult.
Long-term monitoring for contaminants in sediments in the region close to the outfall (the near field) has been established at two sites identified by the geologic maps. These sites are likely to accumulate fine-grained sediments and associated contaminants and thus are sensitive locations for assessing environmental change.
Long-term monitoring for contaminants in sediments in the region distant from the outfall (the far field) has been established in depositional sites downstream from the source of contaminants and at control stations. The geologic maps show that this modest number of stations characterizes and represents the sedimentary environments of large areas of Massachusetts and Cape Cod Bays. The geologic maps provided the framework for the design of a sensitive and efficient monitoring program for assessing environmental change.
Observations of the natural processes that transport sediments (storms, for example) will help determine whether changes in contaminant levels are due to anthropogenic or natural causes.
The observation that a modest fraction of the total amount of contaminants introduced into the Massachusetts Bay system is sequestered in the bottom sediments suggests that dilution is not the best long-term solution for disposal of toxic substances in this coastal system. Instead, reducing the input of toxic substances is the best strategy to ensure the long-term environmental quality of the sediments. The Massachusetts Water Resources Authority is aggressively pursuing source reduction.

Partnerships for Coastal Ocean Science

Coordination of efforts by Federal, State, and academic partners is essential to effectively address complex coastal environmental issues. USGS studies of sediments are part of a coordinated effort to understand the environment of Massachusetts Bay and complement multidisciplinary programs supported by the Massachusetts Environmental Trust, the Environmental Protection Agency, the National Oceanic and Atmospheric Administration (NOAA), the MWRA, and others. Parts of the USGS effort are co-funded by the MWRA and NOAA and carried out with at-sea support from the U.S. Coast Guard. USGS studies have been conducted cooperatively with scientists at the Woods Hole Ocean-ographic Institution, the University of New Hampshire, the University of Mass- achusetts, the Massachusetts Institute of Technology, and the University of New Brunswick.

Continued Monitoring

The USGS will continue to monitor environmental change in Massachusetts Bay. In cooperation with the MWRA, the USGS will continue long-term observations of sediment-contaminant levels and currents in western Massachusetts Bay after the new ocean outfall begins operation in 1998. These observations will provide a unique data set to document environmental change and to assess whether change is caused by natural or anthropogenic processes. A long-term goal of the USGS is to develop similar capabilities in a variety of coastal environments.