David Hughes, the superintendent of Scarborough Sanitary District at the plant on Wednesday, March 1, 2023. Brianna Soukup/Staff Photographer

While Maine has outlawed sludge as an agricultural fertilizer, preferring to landfill it to stop the spread of the harmful forever chemicals lurking within, California has taken the opposite tack.

That state has instead essentially banned sludge landfilling in favor of recycling 90 percent of its organic waste, including sludge, to lower its greenhouse gas emissions. California’s sludge is still spread on farm fields as fertilizer.

Other states fall somewhere in between California, known for an environmental ethic that produced the nation’s first greenhouse gas regulatory program, and Maine, which hails itself as a leader in legislative efforts to stop the spread of harmful per- and poly-fluoroalkyl substances, called “forever chemicals” or PFAS.

In the background, lagging a few years behind the states, the U.S. Environmental Protection Agency has been slowly unrolling its own PFAS plan. It only just released proposed drinking water standards this month. It won’t issue its first federal PFAS guidance for sludge fertilizer until 2024.

“It is a bit of the Wild West out there right now,” said Brian Staley, president of Environmental Research and Education Foundation, a group that studies sustainable waste practices. “California may be ahead of Maine on greenhouse gas emissions, Maine may be ahead on PFAS, and everybody is ahead of the EPA.”

Some states, like Virginia, are waiting for federal guidance, while others, like Maine, have pursued their own policies. The lack of consensus has resulted in a patchwork of contradictory definitions, limits, disclosure requirements and bans of PFAS.


“As a nation, we’re still at the very beginning when it comes to PFAS,” said Sonya Lunder, senior toxics policy adviser for the Sierra Club. “A handful of states, maybe 10, are just starting to think about testing for PFAS in sludge, while the rest are sorting out water. You’ve got to learn to crawl before you walk.”

Maine’s recent disposal crisis shows it is still learning how to manage the never-ending supply of sludge, the semi-solid byproduct of wastewater treatment plants.

Late last month, Juniper Ridge in Old Town, the one state-owned landfill that can accept large amounts of sludge, started turning away sludge deposits, saying it had been landfilling too much of the wet stuff and not enough dry waste to bulk it up. The walls of the landfill were in danger of collapsing.

The emergency closure left sewer operators unsure about what to do with their sludge, which started to pile up in storage trailers and back up in plant overflow tanks. The landfill operator struck a pricey deal to truck it up to New Brunswick to be composted, albeit at much higher rates.

It’s unclear how long that arrangement will last, however, as New Brunswick provincial authorities that oversee sludge importation are under pressure to adopt a moratorium on U.S. waste shipments, just like Quebec did when other U.S. states sent their sludge there.

“It’s a really challenging issue because there are really clear tradeoffs,” Lunder said. “Even within Sierra Club, we have different values competing with each other. We have a group working to ban incineration, reduce landfill carbon emissions, and reduce PFAS, and sometimes we find ourselves on different sides.”


Over half of the 5.2 million tons of sludge produced in the United States each year is applied to farming fields or forests, often for free or far below the price of chemical fertilizers. For decades, it was seen as a win-win, saving farmers’ money and closing the waste recycling loop. But that was before PFAS.

Maine is on the front lines of PFAS legislation. Last year, after a string of farms connected to the state’s decades-old sludge spreading program shut down because of PFAS contamination in soil, water and farm products including milk, Maine became the first state to ban sludge recycling. To date, Maine has identified 56 PFAS-contaminated farms.

At the height of Maine’s sludge spreading days, back in 1997, Maine sent 48% of its 267,000 tons of sludge to farmers to be applied to the fields, turned 38% of it to compost, and buried the final 1% in a landfill, according to state Department of Environmental Protection records.

By 2021, the numbers had flipped: Maine buried 82% of its sludge, composted 11% and spread 6%.

PFAS are a group of over 9,000 manmade chemicals used since the 1950s in industrial and household products like waterproof clothing, nonstick cookware and firefighting foam. They have been linked to cancer, kidney malfunction, immune system suppression and pre-eclampsia in pregnant women.

Their long-lasting carbon-fluoride bonds break down slowly, making them durable and highly resistant to heat, corrosion, water and stains. It also means that PFAS build up over time, in the environment as well as in people. They can be found in rivers, eggs, deer, breastmilk, blood and even rain. And they eventually wind up in the waste stream.


Other states are watching Maine, but no other state has adopted an all-out ban on sludge land spreading, at least not yet. Colorado and Michigan are setting PFAS limits in sludge fertilizer, but at five to 30 times Maine’s old limit. Massachusetts is considering bills to require sludge testing and PFAS limits on sludge.

Arizona’s Pima County, which is home to Tucson, adopted a sludge-spreading moratorium in 2019. The county lifted it a year later, after a University of Arizona study revealed no significant difference in PFAS levels on farmlands fertilized with sewage sludge and those that were not.

Last summer, Virginia increased how much sludge a waste management company can spread on 5,400 acres of farmland north of Richmond without testing for PFAS, despite neighbors’ claims that previous spreading had made them ill. Virginia says it is waiting for the EPA before it adopts its own PFAS rule.

But it is California, the land of the electric vehicle and windmills, that is the antithesis of Maine’s sludge policy: Banning the landfilling that Maine is doing now, while cheering on the very disposal method – sludge recycling on farming fields – that Maine just outlawed.

In 2016, California passed the Short-Lived Climate Pollutant Reduction Strategy, SB 1383. It diverts 90% of organic waste, including sludge, from landfills by 2025, and opens up all every California city and town to sludge spreading, including local communities where it had been banned.

Since 2016, California has spread 3.7 million tons of sludge on its farms, more than any other U.S. state.


So why is California, which is known for using its large market share to propel the U.S. government and the private market forward on environmental issues, zigging when Maine is zagging over sludge? Does it know something Maine doesn’t?

That is a critical question in light of Maine’s current sludge disposal emergency.

California has put the reduction of methane gas – a heat-trapping gas 80 times more potent than carbon – at the heart of its climate campaign. California believes keeping organic waste out of landfills, the third biggest source of human-related methane gas, will slash methane emissions 40% by 2030.

Spreading and mixing sludge with soil creates methane, too, but not as much as burying it.

It’s all a part of California Gov. Gavin Newsom’s plan to achieve carbon neutrality by 2045.

“California communities experience the devastating impacts of climate change every day,” he said in a July 2022 letter. “We need to supercharge our efforts to significantly reduce harmful carbon pollution.”


Some of the same national water and sanitation groups that opposed Maine’s sludge-spreading ban are supporting California’s decision to stick with it, praising it for following the best available science while criticizing Maine for being reactionary and hypocritical.

“The mere presence of PFAS in biosolids, even at trace levels, is causing some state regulators and, at times, the public to react in fear and prematurely limit local options,” the National Association of Clean Water Agencies wrote last year in a policy statement.

The group criticized Maine for failing to understand the extent of the PFAS contamination, let alone the true source of it. Like the Juniper Ridge Landfill operator, Casella Waste of New Hampshire, NACW accused industrial sludge producers – not municipal sludge producers – of being the primary source.

California has been warned. In 2021, the Natural Resources Defense Council issued a report that found contaminated drinking water systems across the state. The state is investigating the source, but at least 69% of disadvantaged communities have PFAS-contaminated public water systems.

California may not be acting on sludge, but it is taking other steps to address the PFAS problem. It has banned PFAS in firefighting foam, children’s products and food wrappers. It is testing soil and water at landfills, airports and military bases. But it has not set any PFAS standards for sludge spreading.

In Maine, lawmakers have pushed back against efforts to overturn their PFAS legislation, including the ban on sludge spreading, saying it made them leaders, not reactionaries. Sen. Stacy Brenner, D-Scarborough, a farmer and environment committee co-chair, said she was surprised to learn last year that California still allows sludge to be spread.


Brenner said Maine has seen the impact that the state’s sludge-spreading program has had on a growing number of Maine farmers. There are still another two years left on the state’s three-year investigation into more than 1,000 sites where sewage and industrial sludge was applied to Maine cropland.

The state has tested about 20% of the sites, state officials say. About 23% of the water tests have come back over the state’s 20 parts per trillion interim drinking water standard. To date, Maine has provided about $1.4 million in financial assistance to those farmers, but the price tag is rising fast.

The need to find a sustainable disposal solution doesn’t mean the state wasn’t wise to stop land spreading, according to lawmakers and environmental advocates.

“I feel like we’re trying to undo the good work that this Legislature did instead of really working together to solve what I think is a smaller problem than the widespread contamination of PFAS,” said Sen. Anne Carney, D-Cape Elizabeth, at a legislative briefing on Maine’s sludge disposal crisis last week.

David Hughes, the superintendent of Scarborough Sanitary District, walks outside the plant early this month. The truck that takes away the plant’s sewage sludge arrived days late because a key landfill stopped accepting the waste, creating a backup and a potential overflow. “If the truck didn’t show I would’ve had to start masking some rash decisions on what to do,” Hughes said. Brianna Soukup/Staff Photographer

There is no question that Maine sludge is loaded with PFAS, including two forms of special concern: PFOA and PFOS. Before the ban, Maine had adopted some of the first PFAS limits for recycled sludges: 5.2 parts per billion of PFOS and 2.5 parts per billion of PFOA. Records show the vast majority of Maine’s publicly operated treatment plants came in over those limits.

All Maine facilities that distribute sludge-derived compost had at least some PFAS in their product.


The Maine Department of Environmental Protection said it shares California’s greenhouse gas goals of cutting the amount of organic waste landfilled, but a 2020 DEP review of PFAS data from state sludges showed that 94% exceeded Maine’s limits for sludge-derived fertilizers at the time.

If spread, the PFAS from the fertilizer could leach into groundwater and exceed federal health advisory drinking water levels of 70 parts per trillion, Deputy DEP Commissioner Dave Madore said. Since then, EPA’s levels have come down more, making it even less likely Maine sludge would be safe to spread.

“The DEP’s screening levels for the beneficial use of waste materials are meant to be protective,” he said.

The EPA has been slow to regulate or restrict the use of forever chemicals, despite knowing about them and their potential risk for more than two decades. Companies keep adding new chemicals to the class, and keep using them to produce everyday household or industrial items like makeup, pizza boxes, or rugs.

The Biden administration says it is taking PFAS seriously. It declared them hazardous substances under the Superfund act, created a national PFAS testing strategy and announced it would study PFAS in sludge. Last week it proposed aggressive new legal limits for safe PFAS levels in drinking water.

But the administration has taken heat from outside and inside the agency for its slow pace. The EPA Inspector General’s Office blasted EPA in 2018 for failing to evaluate the risk of PFAS in sludge. Its lack of transparency put the sludge program “at risk of not achieving its goal to protect public health and the environment.”


In most states, there is no limit on the amount of PFAS chemicals that can lurk in the sludge before it is spread as fertilizer or applied as compost. In most states, there are not even any requirements to test for PFAS concentrations or share the results with a farmer or a government agency.

In January, Michigan ordered a Detroit-area farmer to stop selling beef to schools after the state found “alarming” levels of PFOS in the hay, silage and water he fed his cattle – levels which are lower than other hot spots, but too high for a school, they said. The farmer had used sludge from a nearby sewer plant as a fertilizer.

Michigan bans sludge spreading if PFOS levels exceed 125 parts per billion, which is 24 times greater than Maine’s old limit. If a plant tests above 50 parts per billion, operators must notify a farmer before they can spread the sludge, conduct annual plant tests and take steps to lower its PFOS levels.

Through regulation, Wisconsin won’t allow sludge spreading if PFAS levels exceed 150 parts per billion. Future water pollution and discharge permits are likely to include language prohibiting land application of sludge that exceeds this PFAS threshold.

Illinois, which is the second highest sludge-spreading state in the country at 1.1 million tons, doesn’t put any limits on its PFAS levels in its sludge, but is instead leaving it up to the EPA to determine if a sludge contains too much PFAS to safely spread on agricultural fields.

In Vermont, all sludge must be tested for PFAS prior to its use as fertilizer or compost, and any fertilizer containing PFAS must be labeled as such.


New Hampshire has required PFAS testing of sludge since 2017, but for informational purposes only. The state environmental agency will not start working on standards until November, which means until then, no sludge spreading request can be denied due to PFAS.

As fertilizer costs rise, sludge is in high demand in New Hampshire after a slump following Maine’s ban.

Canadian provinces are facing much the same uphill battle with their federal government as U.S. states.

Some provinces, like Quebec, have created a moratorium on accepting U.S. sludge, saying it has enough sludge of its own to landfill or spread without dealing with Maine’s. New Brunswick is still allowing U.S. sludge to be landfilled there, although it’s unclear how long that will last.

Both provinces stumble over the perception problem: If Maine’s sludge has too much PFAS in it to bury or spread it on farm fields here, why should they allow Maine to kick its problem over the border? Canadian provinces don’t want to become a provincial toilet for the Northeast United States.

Europe has been convinced of the link between sludge spreading and PFAS since 2018, when scientists there concluded forever chemicals sprayed on fields eventually end up in people – either through plants grown there or the milk or meat of the cows that graze or drink there. There also is little consensus among European countries about the risks of recycling sludge.

Denmark set PFAS limits for sewage sludge bound for agricultural use in October 2021, including limits for the sum of a large group of 22 PFAS chemicals. In 2007, Germany set indirect PFAS limits for sludges to be turned into fertilizers, and on the fertilizers themselves; mid-level PFAS products must be marked.

Austria has set a limit for PFAS in sewage sludge agricultural amendments that is 13 times Maine’s pre-ban limit, while Norway is considering limits that are 6 times greater than Maine’s old limits. Sweden, however, is enacting a PFOS limit for sludge recycling that is lower than Maine’s pre-ban limit.

Note: The story was updated Tuesday, March 22, to clarify that Sen. Stacy Brenner, D-Scarborough, learned last year that California was continuing to spread sludge on farm fields. 

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