There’s a bill currently before the Maine Legislature that would permanently ban the sale of biosolids compost and land application of biosolids and sludge. Supporters claim it’s necessary because of PFAS contamination on Maine farms. We are part of a coalition of farmers – including the Maine Farm Bureau – as well as garden centers and landscapers from across the state who believe this is the wrong approach.

Maine people are right to be concerned about PFAS. But making knee-jerk and blanket generalizations in a panic never leads to good policy. It only creates bigger problems than the ones we currently face.

The practice of using residue from municipal wastewater treatment plants – known as “sludge” – and compost made from sludge – generally referred to as “biosolids” – as fertilizer began back in the 1980s. It remains a common agricultural practice throughout the country. It’s important to remember the reasons why this practice started, because they’re even more important today.

Using biosolids and sludge as fertilizer – instead of dumping it in a landfill – reduces carbon emissions that contribute to global warming. Over the past 30 years, we have sequestered thousands of tons of carbons as a result. Farmers across the country continue to use biosolids because they work. They enhance soil health, recycle nutrients and reduce fertilizer and pesticide use.

Land application of biosolids also serves as a critical step in public wastewater treatment that protects public health and the environment. It puts residuals that every community has to manage to productive use.

PFAS contamination at several Maine farms has been an unmitigated tragedy. But virtually everyone agrees this likely was the result of single-source industrial contamination that took place decades ago when the practice of landspreading biosolids first began. Some farms spread industrial sludge containing high levels of PFAS, or spread municipal sludge contaminated by an industrial process where high amounts of PFAS were used.


Today, the use of biosolids is regulated far more closely – and is far safer – than 30 years ago. Research and investigations indicate that typical biosolids with no direct large industrial inputs are unlikely to impact ground and surface waters at levels above U. S. EPA’s health advisory level for drinking water, even with repeated applications. Today, the PFAS conveyed in wastewater, biosolids and other residuals is similar to numerous other incidental, minor releases of PFAS to the environment. The Maine DEP requirements for testing land applied biosolids mean that these products don’t present any greater risk to public health than releases from other daily activities. And Maine’s screening levels – in place since 2019 – are the most stringent in the country, if not the world.

The proposal, therefore, that we must ban all biosolids in order to protect public health is an overreaction. It’s also futile. PFAS are in the furniture in our homes, in our food, in our bodies and in the air. Detectable amounts have even been found in the rain.

A ban doesn’t limit our exposure to PFAS and doesn’t address the terrible legacy situations on several Maine farms. A ban on some sludges but not on others is not based on any science either. There is hardly a residual in existence that doesn’t have some detectable level of PFAS in it.

And assuming we ban the land application of biosolids, where do we put it? Is the solution to concentrate all that sludge in a landfill? Does that make sense without thoughtfully considering the long term consequences?

We can take some measure of comfort that due to restrictions on the production of PFAS, the levels generally being reported in our bodies and our soils are declining. That won’t address the contamination that has already happened. But it does mean that Maine – like all New England states and others across the country – can continue using biosolids as fertilizer and know that doing so makes our environment stronger.

— Special to the Press Herald

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