The challenge of sewage sludge

Do you ever think about what happens to the water from our kitchens and bathrooms after it disappears down the drain? The complex network of pipes leading to the wastewater treatment plant and the final disposal of the sludge that is produced are rarely top of mind.

For decades, Hoosac Water Quality District (HWQD) has been creating compost from the sludge, a byproduct of treating Williamstown's and North Adams' wastewater, by adding wood chips for bulk and pumping air through the pile. Biological pathogens are killed as the material reaches high temperatures. The resulting compost has been sold to plant nurseries, garden centers and others places as fertilizer offsetting the cost of running the plant

This year, however, the HWQD is facing a difficult decision as concerns around the toxicity of wastewater biosolids (sludge and compost) rise.

Sewage Disposal in Massachusetts

In Massachusetts, 46% of biosolids from wastewater treatment plants are applied to the land as fertilizer, 40% incinerated, and 14% landfilled. But there is growing concern about using biosolids as fertilizer due to contamination by PFAS, a group of highly toxic "forever chemicals" in the waste stream. PFAS, widely used in commercial and industrial products, are washed into the wastewater from household goods, food packaging, fire-fighting foam, fabrics, cosmetics, etc

In 2022, Maine banned all land application of biosolids (sludge and compost from wastewater treatment plants) as fertilizer, the first state to do so, after a farm discovered PFAS contamination in their well water.

As we learn more about the impact of PFAS in the waste stream, and the effects on farmland, water and health become better known, states are beginning to impose regulations. Land application is currently banned in Maine. Vermont has strict limits on PFAS levels. Oklahoma is considering a ban. NY State allows biosolids that have lower than 20 ppb (parts per billion) PFAS. Massachusetts has yet to regulate PFAS in biosolids but is considering legislation.

And when state lawmakers or the EPA fail to set limits, some counties and towns are enacting their own regulations. For example, nearby Albany county set a 90 day-moratorium in January. Recently, the Maine Department of Inland Fisheries and Wildlife announced a “do not eat” advisory for wild turkey and deer hunted in three spots, including land surrounding a compost facility in Unity Township.

There is no easy solution. Clearly, the best approach would be to prevent these contaminants from entering the waste stream in the first place. But until that happens we have to continue to manage and dispose of our sewage. Landfills and incinerators are at or near capacity and also have negative environmental impacts including those related to PFAS. As we grapple with what to do, we need to weigh short term costs and benefits against environmental impacts and potential future liability. It's a difficult balance

The options on the table today for HWQD are:

1. truck the sludge (without composting) to a landfill: high cost

2. continue the current composting and land application program (approx. 3000 tons/year): some cost

3. increase the composting and land application program by importing sludge from other communities (up to an additional 5000 to 6000 tons/year) for a fee: revenue generator

The FY26 Town budget is based on option 3.

There is a lot more to say on this topic and more people to hear from. If you'd be interested in an info session of some sort, please let me know.