Print this page

Energy-from-Waste Facility

Covanta SEMASS Partnership 
West Wareham, MA

The Southeastern Massachusetts (SEMASS) Resource Recovery Facility, operating as Covanta SEMASS Partnership, provides the community with an alternative to municipal solid waste (MSW) disposal at landfills. Since opening in 1988, the 95-acre facility has employed a shred-and-burn technology to create refuse-derived fuel, enabling the plant's processing of approximately one million tons of solid waste each year. This is more than one-fifth of all MSW processed/disposed of in Massachusetts annually. The resulting electricity meets the needs of more than 75,000 homes. The facility also recovers nearly 50,000 tons of recyclable metals from pre-combustion magnets and bottom ash annually.

Among the facility’s numerous operational and environmental awards is the American Academy of Environmental Engineers' Honor Award, for its ash technology, and the American Society of Mechanical Engineer's (ASME) solid waste processing facility "Honorable Mention" recognition award in 2007.

Technical Data

Facility Address:

141 Cranberry Highway
West Wareham, MA 02576
(508) 291-4400

Service Area:

Approximately sixty (60) communities in Southeastern Massachusetts, Cape Cod and the metropolitan Boston vicinity

Waste Supply:

Participating municipalities and private haulers to deliver approximately one million tons per year

Energy Market:

Electricity generation for plant use and export to NSTAR (electric and gas utility company)


3,000 tons per day of processed refuse fuel

Process Lines:

Three Riley-Stoker boilers each with 375 million British thermal units (MBtu) per hour design heat release rate
Steam Conditions at Boiler Outlet: 300,000 pounds per hour @ 650 pounds per square inch absolute (psia)/750°F


One 54 megawatt (MW) nominal condensing unit and one 30 MW condensing unit

Air Quality Control:

The facility utilizes Dry Scrubbers for acid gas control, Carbon injection for mercury control and Electrostatic Precipitators and Baghouses for particulate control.

Stack Height:

345 feet

Secondary Materials Recovery:

Recovery of ferrous (steel) and non-ferrous (iron and alloys) metals