The Massachusetts Bay Disposal Site (MBDS) is located approximately 20 kilometers (10.8 nautical miles) southeast of Manchester, Massachusetts, centrally located within Massachusetts Bay and situated adjacent to the Stellwagen Bank National Marine Sanctuary. MBDS was formally designated as an Ocean Dredged Material Disposal Site (ODMDS) by the United States Environmental Protection Agency (USEPA) in 1993. In 2018 the USEPA temporarily expanded the MBDS to include a portion of the historic Industrial Waste Site (IWS) adjacent to MBDS to allow for restoration of the former waste site with dredged material generated from deepening Boston Harbor. The recently expanded MBDS, which includes portions of the historic IWS, is approximately 15.8 square kilometers (4.6 square nautical miles) in size, centered at 42° 25.55’ N, 70° 35.13’ W (NAD 83). Water depths within the expanded MBDS range from 74 to 92 meters (243 to 302 feet) with the exception of several shallower glacial drumlins in the expanded portion of MBDS. Additional information about the monitoring and management of MBDS, including the current Site Management and Monitoring Plan (SMMP) and the Industrial Waste Site restoration project, can be found on the EPA Region 1 Ocean Dumping web page.