The Nyanza Chemical Waste Dump Site ("Nyanza Site") Natural Resource Damages (NRD) Trustee Council is responsible for planning, implementing, and overseeing the restoration, replacement and acquisition of the equivalent of natural resources and natural resource services that were harmed when hazardous substances and materials, principally mercury, were released from the Nyanza Site located in Ashland, Massachusetts. The Nyanza Site was listed on the National Priorities List in 1983; clean-up actions supervised by the U.S. EPA began in 1987. (See Background for more information.)

To compensate for natural resources and natural resource services injured as a result of mercury contamination, the Trustees seek to restore wetland, floodplain, and riverine habitats and species that utilize or historically utilized these habitats, particularly birds and riverine fish, as well as other aquatic organisms, amphibians, reptiles, and mammals.

The Trustee Council has spent the past several years reaching out to government agencies, local officials, non-governmental organizations, and the general public for help in identifying potential restoration projects that would benefit the types of natural resources harmed at or from the Nyanza Site. The results of this outreach, and preliminary screening of proposed projects, have been incorporated into a Draft Restoration Plan/Environmental Assessment.


The Nyanza Natural Resource Damages Trustee Council has released a Final Restoration Plan/Environmental Assessment pdf format of nyrp.pdf
file size 6MB that identifies twelve restoration projects to restore natural resources and natural resource services that were injured as a result of the release of mercury and other hazardous substances from the Nyanza Chemical Waste Dump Superfund Site located in Ashland, Massachusetts. The Trustee Council - comprised of the Massachusetts Executive Office of Energy and Environmental Affairs, represented by the Massachusetts Department of Environmental Protection, U.S. Fish and Wildlife Service, and National Oceanic and Atmospheric Administration - worked with citizens, community and environmental groups, local and regional officials, and state and federal agencies to identify restoration project ideas. The final plan also incorporates public comments on an earlier draft. A copy of the Final RP/EA will be available at the Ashland Public Library, 66 Front Street, Ashland, MA and online at http://www.mass.gov/dep/cleanup/sites/nrd/nrdny.htm.

The Final Concord River Diadromous Fish Restoration Feasibility Study is now available.  You can now view the Executive Summary, Study and All Appendices.

Appendix A - Figures  pdf format of Appendix A - Figures
file size 15MB

Appendix B - Photos  pdf format of Appendix B - Photos
file size 8MB

Appendix C - Historical Aerial Imagery  pdf format of Appendix C - Historical Aerial Imagery
file size 1MB

Appendix D - Concept Plans  pdf format of Appendix D - Concept Plans
file size 1MB

Appendix E - Photographic Renderings  pdf format of Appendix E - Photographic Renderings
file size 1MB

Appendix F - Hydraulic Model Output  pdf format of Appendix F - Hydraulic Model Output

Appendix G - MHC Correspondence  pdf format of Appendix G - MHC Correspondence
file size 1MB

Appendix H - Historic & Archaeological Report  pdf format of Appendix H - Historic & Archaeological Report
file size 8MB

Appendix I - Public Comments  pdf format of Appendix I - Public Comments
file size 3MB

Executive Summary  pdf format of Executive Summary
file size 2MB

Concord River Fish Restoration Final Report  pdf format of Concord River Fish Restoration Final Report
file size 3MB

Trustee Council

The Nyanza NRD Trustee Council includes representatives from the Commonwealth of Massachusetts Executive Office of Energy and Environmental Affairs, U.S. Fish and Wildlife Service (USFWS), and the National Oceanic and Atmospheric Administration (NOAA). Within EEA, the Massachusetts Department of Environmental Protection (MassDEP) administers the NRD Program. See Contact Information to get in touch with Trustee Council representatives.

These agencies signed a Memorandum of Agreement (MOA) in 1998 to act jointly to engage in restoration activities in the Sudbury/Assabet/Concord River watershed to benefit the natural resources that are entrusted to their care and management and that were harmed by contaminants released from the Nyanza Site.

Decisions regarding the expenditure of funds for restoration activities are made jointly based on unanimous consent by the Trustees. The MOA outlines a framework for the cooperative development and implementation of a Restoration Plan to restore, replace, and/or acquire the equivalent of the natural resources affected by the release of hazardous substances from or at the Nyanza Superfund Site. In addition, EPA and the DEP were signatories to the MOA to ensure coordination between Trustees and the remedial agencies.


Per a Consent Decree entered in 1998, the Commonwealth of Massachusetts, NOAA, and the USFWS recovered $2.8 million for injuries to ecological resources and $230,769 for injuries to groundwater from mercury and other hazardous materials and substances originating at the Nyanza Site located in Ashland, MA. Interest earned on the settlement funds has increased the total amount of funding available for restoration activities to approximately $3.7 million. Per federal statute, NRD funds must be used to "restore, replace, or acquire the equivalent of" the injured resources. For the Nyanza NRD settlement, the injured resources include the Sudbury River, adjacent wetland and floodplain habitats, and species supported by those habitats.

The 35-acre Nyanza Site is located in an industrial area of Ashland, south of the Sudbury River. From 1917 to 1978, companies that operated on the Site produced textile dyes and intermediates and generated large volumes of industrial wastes that contaminated soil and sediments, groundwater and surface water, wetlands, and the Sudbury River. The principal contaminant of concern is mercury; other contaminants are chromium, arsenic, lead, and organic compounds such as dichlorobenzene and chlorobenzene. Since 1987, the EPA has addressed contaminants through interim cleanup actions and four long-term remedial phases focusing on source control and cleanup of the soil, groundwater, wetlands and drainage ways, and the Sudbury River.

Of particular concern to the Trustees and the basis for much of the NRD claim is the Nyanza Site's impact on the Sudbury River, its floodplain, and associated natural resources. According to EPA, mercury and chromium were used as catalysts in the production of textile dyes from 1917 to 1978. Approximately 2.3 metric tons (2,300 kg) of mercury were used per year from 1940 to 1970, with approximately 45 to 57 metric tons of mercury released to the Sudbury River during this period (U.S. EPA, 2004). Mercury contamination of open water habitats, as well as surface soils and exposed sediments downstream from the Nyanza Site, reduced the quality of the habitat for fish, amphibians, reptiles, other aquatic organisms, birds, and mammals. In 1986 the Massachusetts Department of Public Health imposed a Freshwater Fish Consumption Advisory for the Sudbury River from Ashland to its confluence with the Assabet and Concord rivers because of elevated levels of mercury in fish tissue. This advisory has continued until the present day. EPA's 2008 Final Supplemental Baseline Ecological Risk Assessment (BERA) also verifies, through site-specific studies, that mercury concentrations are elevated in water and sediments downstream of the Site, as well as in benthic invertebrates, fish, insectivorous birds (e.g., tree swallow, red-wing blackbird); piscivorous birds (e.g., belted kingfisher, hooded merganser); and mammals (mink).

The 2008 BERA found that although there was evidence of elevated exposure, the concentrations (in different species/biota) do not cause "population-level" effects according to EPA-defined thresholds. However, adverse effects below this threshold level are likely occurring to a variety of species within the site-affected area.

The mainstream Sudbury and Assabet Rivers join to form the Concord River, which flows into the Merrimack River in Lowell, draining a watershed of 377 square miles. Including tributary streams, an estimated 260 named river miles exist in the watershed. Several watershed plans identify habitat and recreational resources, as well as critical water quality, water quantity and other issues and priorities across the watershed.

The federal government has designated portions of the Sudbury, Assabet and Concord Rivers as National Wild and Scenic Rivers in recognition of their unique ecological and cultural resources. Similarly, the Great Meadows and Assabet River National Wildlife Refuges were created to protect the exceptional wildlife and habitat resources present in those areas, most notably a large variety of birds. Great Meadows marshes also support amphibians and reptiles. Along with habitat for numerous threatened or endangered species, the Assabet Refuge also includes several rare wetland types and a number of vernal pools, which are considered to be habitats of special concern.


Publications from the Nyanza NRD Trustee Council, organized by date with recent items at the top:

Administrative Record

The administrative record is the hard-copy record of all the documents associated with the Nyanza Chemical Waste Dump Site Natural Resource Restoration project. The administrative record includes the full copies of all the restoration project ideas submitted to the Nyanza Trustee Council for consideration as well as copies of public presentations, minutes from meetings, etc. The administrative record can be viewed at the Ashland Public Library:

66 Front Street
Ashland, MA 01721
(508) 881-0134

The library hours are:

Mon. Closed
Tue.-Thu. 10am-8pm
Fri. 2pm-5pm
Sat. 10am-5pm
Sun. Closed.

The administrative record is a large binder kept in the small room off the lobby. The reference librarian can assist you in locating it.

Contact Info

Mass Department of Environmental Protection
Rosemary Knox

National Oceanic and Atmospheric Administration
Eric Hutchins

U.S. Fish and Wildlife Service
Molly Sperduto

Mass Department of Environmental Protection
Karen Pelto, Nyanza Restoration Coordinator