A “polluting event” on a farm can have a consequential impact on the farm’s health, the farming business, and pose potential environmental liability. In this blog, we look at a couple of the current environmental issues agriculture is facing – nitrates and per- and polyfluoroalkyl substances (PFAS).
Much of the environmental attention for agriculture in the early 2000s focused on air quality. The National Air Emissions Monitoring Study (NAEMS) was intended to develop air emission factors for various agricultural operations. Although there was an update in 2022, the air issue has taken a backseat to more-pressing environmental issues for agriculture.
Nitrates
A recent (2025) report in Iowa, Currents of Change, has brought the concern about nitrate (and phosphorus) associated with agriculture back into the news cycle, at least for that region. The report evaluates pollution in two rivers in Iowa: the Des Moines and the Raccoon. The report states that agriculture (chemical fertilizer and manure) is a major contributor to the nutrient loading in the rivers.
The issue of nutrient management on farms has been an issue for decades. While nitrate is essential for plant growth, excess nitrate in drinking water is a contaminant that can be fatal, especially for babies (blue baby syndrome or Methemoglobinemia).
Nutrients, including nitrates, affecting surface waters can lead to eutrophication. In 2014, excess nutrients in Lake Erie led to Harmful Algal Blooms that interrupted the drinking-water supply for half a million people in the Toledo, Ohio, area.
This is not just an isolated concern; it is a global concern. The impacts have been documented in Europe, Asia, the Middle East, South America, and North America.
Over the past decade and a half, we have worked on several sites in the United States and one site in New Zealand regarding nitrate in groundwater. The focus of our investigations has included defining the source of nitrate. Often, this comes down to differentiating nitrate from manure versus nitrate from chemical-based fertilizer.
Among the significant environmental issues facing agriculture are concerns about nitrate in groundwater and surface water and PFAS impacts from biosolid application.
In a 2022 publication in Science Direct, they do a deep dive into the issue of nitrate-impacted groundwater. They also include a map that shows “risk of nitrate pollution in groundwater aquifers in the USA.”
The Currents of Change report states, “The Rivers (in Iowa) often contain some of the highest nitrate levels in the U.S. and routinely exceed the health-based drinking water standard, threatening human health and increasing the cost and complexity of water treatment.”
As outlined in the report from Iowa, addressing nitrate in groundwater and surface water continues to be a significant environmental issue. Before developing effective plans to address nitrate, it is incumbent to understand the source of the nitrate (i.e., chemical or manure).
For more information about scientific tools to help determine if the source of nitrate contamination is chemical or manure, see our short video, “Isotopes Can Help Determine the Source of Nitrates in Groundwater.”
As significant as the nitrate issue is, agriculture is facing another potentially more consequential environmental liability issue – PFAS.
PFAS
There have been isolated instances where off-site sources have impacted a farm’s groundwater. Most notably, a 4,000-head dairy farm in Clovis, New Mexico, was forced to close due to using groundwater that was contaminated with PFAS by the adjacent military base that used Aqueous Film Forming Foam or AFFF (containing PFAS) to fight fires.
By far, the most complex environmental issue facing agriculture is PFAS associated with the practice of land application of biosolids as a soil amendment to farm fields across the United States. In many instances, these biosolids contain PFAS, and some testing has shown uptake of the PFAS into crops and livestock.
While most of the concern has focused on biosolids that may have received industrial wastewater (e.g., plating, paper mills, etc), all wastewater plants, and, by default, all biosolids, carry some risk of being impacted by PFAS. There are several potential sources of PFAS in residential homes, including carpeting, stain- and water-resistant clothing, cosmetics, etc. PFAS from these sources can end up in residential sewers, which end up in biosolids at the municipal wastewater treatment plant, and, ultimately, on farm fields.
Beyond the concerns of PFAS in groundwater, livestock, and crops, the Biden Administration designated two PFAS, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), as “hazardous substances” under the Comprehensive Environmental Response Compensation and Liability Act (CERCLA), aka Superfund. This designation presents significant potential legal liability for the farmer relative to “contaminated” property under Superfund liability.
The US EPA has indicated that they are not going to enforce Superfund liability on passive receivers of PFAS (such as a farmer who land-applied PFAS-contaminated biosolids), but the fact remains that the farm may have PFAS in the ground. Additionally, this liability may be tempered by the CERCLA exemption of “normal application of fertilizer.” Under CERCLA section 101(22)(D), the definition of “release” explicitly excludes “the normal application of fertilizer.”
However, the issue of “normal application of fertilizer” is being debated. Inside EPA (paywall) recently addressed this issue in an article. Quoting Jeff Porter with the law firm Holland & Knight, “normal land application’ begs the question: ‘what’s normal?”
The concerns about nutrient impacts on water and the concerns about PFAS impacts are not going to be easily solved. But, for our part, we believe the use of good scientific principles should be the foundation for effective solutions.
For some additional insight on agriculture, see Looming Food Crises or More Catastrophizing? Also, see our resource pages:
Environmental Advice
Dragun Corporation has assisted the regulated community with environmental compliance, assessment/remediation, and litigation support since 1988. If you need assistance with a PFAS-related issue, including litigation support, contact Jeffrey Bolin, M.S., CHMM, at 248-932-0228, Ext. 125.
Alan Hahn drafted this blog. Alan has an undergraduate degree in Environmental Studies and completed a graduate program in Environmental Management. He has worked in environmental management for more than 45 years. He has written hundreds of blogs and articles. His published work includes Michigan Lawyers Weekly, Detroiter, Michigan Forward, GreenStone Partners, Manure Manager Magazine, Progressive Dairy, and HazMat Magazine.
Jeffrey Bolin, M.S., reviewed this blog. Jeff is a partner and senior scientist at Dragun Corporation. He is a published author, a frequent speaker, and an expert witness. His expertise in environmental due diligence, PFAS, vapor intrusion, and site assessments has led to projects in the US, Canada, and overseas. See Jeff’s Bio.
Follow Dragun Corporation on LinkedIn, X, or Facebook.
Sign up for our monthly environmental newsletter.
Principled Foundation | Thoughtful Advice | Smart Solutions
Established in 1988