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Covanta SEMASS

SEMASS Facility Photo

Covanta SEMASS

The Southeastern Massachusetts Resource Recovery Facility (SEMASS) converts municipal solid waste (MSW) to steam and electricity while providing MSW disposal for participating communities in Cape Cod, southeastern Massachusetts, and the Boston metropolitan area. Opened in 1988, the facility is located on a 95-acre site on Route 28 in Rochester, Massachusetts. It is designed to receive MSW, magnetically separate and shred it to produce processed refuse fuel (PRF), which is fired in specially-designed waterwall boilers. SEMASS processes more than 1 million tons of MSW annually. The resulting electricity serves nearly 40 communities and meets the needs of more than 75,000 homes. It is the largest Energy-from-Waste (EfW) facility in the Commonwealth of Massachusetts. 

Commercial Operation:


Waste Processing Capacity:

3,000 tons per day of processed refuse fuel

Air Pollution Control Equipment:

Dry scrubbers for acid gas control, carbon injection for mercury control, and electrostatic precipitators and baghouses for particulate control

Energy-from-Waste System:

Three refuse derived fuel boiler units, four hammermill waste shredders 

Energy Generation:

Two turbine-generators: one 54 MW nominal condensing unit and one 30 MW condensing unit 

Awards and Recognition:

  • 2017 Environmental Business Council of New England (NE-EBC) John A.S. McGlennon Environmental-Energy Award for Corporate Leadership 
  • 2017 Covanta Gold Star award for Safety, Health, and Environmental Excellence
  • 2016 SWANA Silver Excellence Award
  • 2007 American Society of Mechanical Engineers (ASME) Materials & Energy Recovery Division (MER) Facility Recognition Award
  • Community Initiatives

    Mistic Aquarium


    Mystic Aquarium

    Covanta SEMASS recently teamed up with Mystic Aquarium and our SECONN, Haverhill, and Bristol facilities to create an interactive exhibit showcasing how discarded marine debris can be turned into clean energy. This exhibit, entitled “Covanta Cove,” includes a water feature depicting a local pond, a diorama reflective of a local CT neighborhood, a scale-model of a typical Energy-from-Waste facility, and two giant, mobile claws. Visitors can maneuver the cranes to collect debris from the cove’s pond, and then deposit the “waste” into receptacles for processing at the facility. It’s a great way for people to experience the EfW process first hand.

    Ton of Thanks

    Covanta SEMASS honored the Cape Cod Cooperative Extension’s (CCCE) Hazardous Materials Program with its “Ton of Thanks” award for its exceptional leadership in mercury education and awareness. This award is part of Covanta’s celebration of removing over one ton of mercury from the waste stream through events and public awareness. With the help of CCCE, Covanta SEMASS has collected over 1,800 pounds of mercury thermostats and other items since 2004. 


    Covanta SEMASS

    141 Cranberry Highway

    West Wareham, MA  02576



    Mark Davis


    Visit Our Facility!

    If you would like an escorted tour of our facility, please reach out. We welcome the opportunity to show you how our resource recovery process works.

    Click here for tour checklist (PDF)

    All tours must be scheduled in advance. Please contact Cynthia Duggan, facilities administrative assistant, at 508-291-4450 or email

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