A call for sediment regulation

Eight years ago, the brink of a huge agricultural problem was discovered in Maine when PFAS (per- and polyfluoroalkyl substances) emerged on a third-generation dairy farm. Toxic fluoride compounds in water, soil, pasture grass and farm milk have their roots in sewage sludge spread across fields more than a decade earlier.

The U.S. Environmental Protection Agency (EPA) and most state departments of agriculture continue to promote land spreading as a “beneficial use” of sediment, even though they know that the “forever chemicals” it contains pose serious health risks by disrupting hormonal systems. immune and reproductive systems and increasing the risk of various cancers.

Of the more than 700 chemicals identified by the EPA in residual sewage sludge, which are known in the industry as “biosolids,” PFAS are almost universal. “What’s unique about Maine is that we’re actually looking for it,” says Sarah Alexander, executive director of the Maine Organic Farmers and Gardeners Association (MOFGA). To date, state agencies in Maine have discovered more than 70 farms contaminated with PFAS, several of which have had to cease all food production.

In 2022, Maine became the first state to ban the land application of sludge and the sale of compost containing sludge. Alexander notes that larger U.S. food supplies lack such protections. According to the EPA, more than half of the nation’s sewage sludge is used on land each year, with 31 percent of it spread on agricultural land and the remainder going to places such as home gardens, landscaping, sports fields, golf courses and parks .

In an effort to force faster adoption of federal regulations regulating PFAS in sediments, MOFGA announced last week its intention to join a lawsuit against the EPA with Public Employees for Environmental Responsibility (PEER), an environmental watchdog group that notified the EPA of its intention to file a lawsuit in February. The action follows sediment contamination incidents that affected farmers in Texas, South Carolina, Michigan and other states.

“The easy state-by-state approach won’t work,” Alexander says; a coordinated and timely response from the Environmental Protection Agency (EPA), the U.S. Department of Agriculture, and the Food and Drug Administration is needed.

The EPA plans to complete a risk assessment this year of two PFAS compounds commonly found in sediment, but Alexander says it’s “too little, far too late.”

The Clean Water Act requires EPA to review sewage sludge regulations every two years and address contaminants that may be harmful. According to MOFGA, EPA has only published nine regulations governing the land management of sewage sludge. MOFGA says at least 12 of the PFAS found in sediments so far have clear scientific evidence indicating public harm.

Evidence about sediment risks has been accumulating for decades. A 1997 report by Cornell University’s Waste Management Institute called on the EPA to adopt more stringent sludge regulations and “take a closer look at sewage sludge content and conditions of use.”

“Sewage sludge is widely suspected to be a major sink for PFAS,” the researchers wrote in 2005, because the compounds adsorb to solids during wastewater treatment. Christopher Higgins, a professor of environmental engineering at the Colorado School of Mines, co-authored this research and worked with colleagues on a study published in 2011 that found that PFAS levels in soil increased in proportion to the amount of municipal sludge applied. By then, the EPA had encountered record high levels of PFAS in Alabama pastures containing sediment containing waste from a fluorochemical manufacturer.

Higgins recalls trying to convince the EPA and wastewater industry associations that a multimillion-dollar research program was needed to assess the risks that PFAS in sediments could pose to groundwater, soil health and the food supply, but says there was “no real interest in doing the research and asking difficult questions.” When he presented the study results to waste officials, he recalls that “they wanted to put their heads in the sand and say there was no problem.”

When the EPA established drinking water standards for some common PFAS compounds this spring, the agency acknowledged that “there is no level of exposure to these contaminants without risk of health effects, including some cancers.” The EPA describes PFAS as an “urgent public health and environmental issue,” but MOFGA estimates that regulations do not yet live up to the rhetoric. “We know there are risks,” Alexander says. “We want them to take action.”

The widespread use and disposal of PFAS is at the root of ongoing sediment contamination, the EPA wrote in a statement last year. Currently, there are no viable ways to remove PFAS from sediments on a large scale or to remediate sediment-contaminated agricultural soils.

The plight of farmers whose lives have been upended by toxic sludge has convinced Maine to lead the nation in passing a phased ban on the use of PFAS in most products. Policymakers have realized that the only real way to manage such persistent and harmful chemicals is to significantly eliminate their use.

“No one can undo the historic contamination of our land,” testified one Maine farmer who lost his home and business to sediment. “But now we know enough to turn off the tap.”

This article first appeared in Marina Schauffler’s Substack newsletter ContamiNation.