The situation currently playing out in the City of Gardner, Massachusetts, is a microcosm of the situation playing out across the Northeast as options for biosolids management continue to dwindle. Maine has banned land application.  Incinerators in Rhode Island, Connecticut and Massachusetts, continue to age and have unplanned downtime, disrupting the movement of biosolids out of water resource recovery facilities (WRRFs).  Landfill capacity is limited in the Northeast, especially when it comes to biosolids (see Landfill Capacity in the NE — NEBRA (nebiosolids.org)).  NEBRA’s June Lunch & Learn webinar painted a bleak picture for the future of the landfill option for biosolids management in the region.

The City of Gardner owns a WRRF at 52 Plant Road in neighboring Templeton that is operated by Veolia.  The City also owns and operates a “monofill” – a landfill for sludges from the City’s WRRF. The landfill is expected to reach its useful life in 2025, or possibly make it to 2027, but there is less than 4 years of capacity remaining now. Back in 2020, the City proposed to expand its existing 6 acre landfill by 4.2 acres to give the site an additional 17 years of capacity. After a study of numerous alternatives by Woodard & Curran, the City chose the landfill expansion option as the most economically feasible. The landfill expansion cost is not insignificant at $6.2 million, not including the cost to cap the old landfill.  The City formally applied for the landfill expansion in early 2022 [Application Details (state.ma.us)].

The City has been investing for some time in processes to reduce the volume of sludges produced at the Templeton facility, including centrifuges. According to data in the Biosolids Facility Report | ECHO | US EPA, the Gardner WRRF slashed it sludge production in 2020, which will certainly help extend the life of the sludge landfill.

Local environmental advocates, like Alan Rousseau, a landfill neighbor and co-founder of Gardner Clean Air and board member North County Land Trust, call the landfill expansion “a 1980s type sludge solution” and instead are calling for a more sustainable solution. What that is exactly has yet to be determined.  Local environmental groups are contesting the wetlands permit for the landfill expansion and the Massachusetts Department of Environmental Protection is requesting an Environmental Impact Report from the City due to the wetlands concerns. Gardner sludge landfill expansion needs environment study (thegardnernews.com).

City officials state that they are continually looking at different options but are finding the possibilities not cost effective, prohibited by state law, or the technologies that have not been developed to the point to make it feasible. Gardner has hired SoMax to do a feasibility study and estimate the cost to construct a hydrothermal carbonization (HTC) facility for treating its biosolids. According to sources at SoMax, the feasibility study involved lots of analysis of Gardner’s sludge and an evaluation of the input requirements. HTC can be quite energy efficient and sludges are more easily dewatered following HTC. According to SoMax, HTC can also improve the quality of the “hydrochar” end products when followed by drying or gasification/pyrolysis. The Gardner WRRF treats about 3 million gallons per day, on average, and the HTC operation probably won’t be cost-effective unless Gardner were to accept outside sludges for treatment.

At this time, the City of Gardner is pursuing the expansion of the existing landfill. What the future holds for Gardner is still unknown. NEBRAMail will be following this story to see if the City investigates additional resource recovery options or additional biosolids treatment capacity for other communities. With landfills reaching capacity all around the region, lots of communities will need to make similar decisions soon about what to do with their solids waste and biosolids.