New MassDEP waste-composition data shows cardboard declines, film and residential food waste rise; C&D share at combustors falls

John Fischer presented MassDEP's 2025 waste-characterization results, which sample municipal waste combustor tip-floor loads that represent roughly two-thirds of the state's municipal solid waste by disposal. "When we look at our salvage disposal, we see municipal solid waste essentially flat from our baseline year of 2018, but a really significant increase in our non-municipal solid waste, which is really driven primarily by construction demolition materials," Fischer said earlier in the meeting.

Key findings Fischer highlighted for 2025:

- Cardboard/corrugated (the category for which waistband enforcement is most frequently used) declined from about 6% in 2022 to approximately 4.2% in 2025, with most of the decline in the industrial/commercial/institutional (ICI) stream.

- Compostable paper (paper towels, napkins, compostable food-serviceware) rose to about 9.6% of the sampled waste stream.

- Plastic film and "other film" categories continued an upward trend and together represent a growing share of the plastic total.

- Construction and demolition (C&D) materials recorded a notable drop at municipal waste combustors in 2025 compared with prior cycles; MassDEP staff suspect the material has been routed differently (for example, to C&D-specific facilities or transfer-station/landfill pathways), not that the material vanished from the overall waste stream.

- Residential food waste increased as a share of residential loads (from roughly 21% in 2022 to about 26% in 2025), while commercial food-waste percentages were largely steady.

Fischer cautioned that the characterization percentages always sum to 100%, so substantial changes in one large category (for example a C&D shift) will alter other categories' shares even if actual tonnages have not changed in the same way. He also noted the sampling protocol alternates seasonal windows and includes confidence-interval considerations in the formal reports.

All study reports, the methodology guidance and summary spreadsheets are posted on MassDEP's Solid Waste Master Plan webpage; Fischer said MassDEP will follow up with additional analyses on waistband materials and can produce combined waistband-percentage and tonnage calculations on request.

The department and committee members raised several open items for follow-up: whether to expand sampling to transfer stations/landfills, requests for the absolute tonnages that correspond to the percentages (2024 disposal totals can be used to estimate tonnages; MassDEP suggested each 1% equals about 45,000 tons using the 4.5-million-ton 2024 baseline) and targeted sampling to clarify where displaced C&D materials are now going.