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Livestock emissions still up in the air

Congress exempts farms from reporting air pollutants to federal agencies, leaving states to deal with animal waste releases

by Britt E. Erickson
April 2, 2018 | A version of this story appeared in Volume 96, Issue 14
A photo of pigs confined in a small space.

Credit: AP | Livestock producers are off the hook for reporting air emissions to federal agencies thanks to legislation attached to the omnibus spending deal.


In brief

The air near large-scale industrialized pig, chicken, and dairy cow operations not only stinks, it can be hazardous to public health. But no one knows exactly what is in the air surrounding such facilities because the U.S. livestock industry has long been exempt from reporting hazardous air emissions under federal law. A 2017 court decision would have upset that status quo by requiring farmers and ranchers to report certain emissions from animal waste, such as ammonia and hydrogen sulfide, when released above certain thresholds. Congress stepped in last month to pass a bill that once again exempts many farmers and ranchers from reporting air emissions to federal authorities. It is now up to the states to determine how best to deal with air emissions from the livestock industry.

A constant rotten stench, biting flies, and air that burns your eyes and throat. That is how neighbors of some large-scale animal farms describe the environment around their homes. They don’t enjoy going outdoors, and they don’t open their windows.

Such is life for Jeff and Gail Schwartzkopf, who purchased their house in rural Rudd, Iowa, four years ago. Shortly after they moved in, the couple discovered that they were getting new neighbors. Thousands of squealing pigs moved in less than 600 meters from their property line, and “their lives changed forever,” according to testimony of Mark Kuhn, a farmer and county supervisor in Iowa. Kuhn was speaking in favor of requiring large-scale animal facilities to report dangerous air emissions during a March 8 subcommittee hearing of the U.S. Senate Environment & Public Works (EPW) Committee.

Air quality is not just a problem near pig farms in Iowa; similar concerns have arisen elsewhere, such as dairy operations in Wisconsin, egg-laying facilities throughout the Midwest, and broiler chicken houses in Maryland. For decades, the U.S. agriculture industry has moved to increase profits by geographically concentrating facilities. The size of these facilities has increased over the years, and today tens of thousands of animals are raised in confined spaces. As emissions from such facilities go largely unchecked, concerns about negative impacts on the environment and public health are on the rise.

Just days after the hearing, however, lawmakers passed the Fair Agricultural Reporting Method (FARM) Act (S. 2421), a bill that exempts farmers and ranchers from reporting air emissions to federal agencies. The bill was attached as a rider to the omnibus federal spending bill that funds the federal government for the remainder of fiscal 2018 (see page 16). Lawmakers stepped up in response to a recent court decision that would have required farms to report emissions of hazardous pollutants such as ammonia and hydrogen sulfide when they exceeded specific thresholds.

Credit: C&EN/Shutterstock
Ammonia emitters
Animal waste contributes 50 to 85% of ammonia emissions in the U.S., according to EPA estimates. Here's a look at the top five sectors by metric tons of NH3 emissions per year.
Source: EPA 2014 National Emissions Inventory v.2
Credit: C&EN/Shutterstock
Ammonia emitters
Animal waste contributes 50 to 85% of ammonia emissions in the U.S., according to EPA estimates. Here's a look at the top five sectors by metric tons of NH3 emissions per year.
Source: EPA 2014 National Emissions Inventory v.2
Credit: C&EN/Shutterstock
Ammonia emitters
Animal waste contributes 50 to 85% of ammonia emissions in the U.S., according to EPA estimates. Here's a look at the top five sectors by metric tons of NH3 emissions per year.
Source: EPA 2014 National Emissions Inventory v.2

The reporting exemptions, however, leave people like the Schwartzkopfs with little information on what is in the air they breathe. They worry about their health and suffer from fatigue, digestive issues, and insomnia, Kuhn testified. With livestock operations off the hook at the federal level, states are now responsible for determining whether and how to address pollution from the industry.

Exempting farm emissions

Since 2008, the U.S. Environmental Protection Agency has exempted farmers and ranchers from air emissions reporting requirements under a 1980 federal law known as Superfund, or the Comprehensive Environmental Response, Compensation & Liability Act (CERCLA). EPA’s 2008 rule also exempted farms from reporting hazardous air releases under the 1986 Emergency Planning & Community Right-to-Know Act (EPCRA) if the farm had fewer animals than a so-called concentrated animal feeding operation.

EPA interprets the law to exclude farms from EPCRA requirements because they use substances like animal waste in routine agricultural operations. In guidance released in October, EPA noted that reporting under EPCRA is required for facilities that produce, use, or store a hazardous chemical, and EPCRA specifically excludes substances used “in routine agricultural operations” from the definition of a “hazardous chemical.” EPA claimed in 2008 that emissions reports “are unnecessary because, in most cases, a federal response is impractical and unlikely.”

Others in favor of exempting farms from emission requirements note that CERCLA’s purpose is to require industrial reporting so that federal, state, and local officials can evaluate how to respond in an emergency situation. CERCLA gives EPA tools to clean up hazardous waste sites and hold responsible parties accountable, Senate EPW Committee Chair Sen. John Barrasso (R-Wyo.) said at the March 8 hearing. “When applied to the everyday activities on ranches and farms, it makes very little sense,” he said.

Photos of egg-laying chickens in battery-style cages and egg-laying chickens in cage-free housing confined in a small space.
Credit: Shutterstock
Most egg-laying hens in the U.S. are raised in conventional battery cages, but a growing number of producers are switching to cage-free housing because of animal welfare concerns.

Had EPA not exempted them in 2008, as many as 100,000 farms and ranches would have had to comply with CERCLA and EPCRA reporting requirements. However, many are not large industrialized facilities spewing out pollutants at high enough concentrations to make people in the community sick. Some of them manage manure from thousands of animals by relocating the waste to farms that use it as fertilizer to grow corn, soybeans, and other crops. In other cases, such as cattle raised on pastures, emissions are spread out over a large area.

When applied to such operations, CERCLA and EPCRA create “needless requirements that burden the agricultural community while providing no environmental or public health benefit,” Todd Mortenson, a South Dakota rancher honored by the Sand County Foundation for his land conservation practices, said at the Senate hearing. He testified at the hearing on behalf of the National Cattlemen’s Beef Association, which represents cattle producers and family ranchers.

Nevertheless, environmental and citizen groups had challenged EPA’s rule exempting farms from emissions reporting, saying that EPA does not have the authority to exempt any industry from CERCLA and EPCRA requirements. In April 2017, the U.S. Court of Appeals for the District of Columbia Circuit ruled in favor of the plaintiffs, putting farms back on the hook to report emissions. At EPA’s request, the court delayed the effective date until at least May 1, 2018, so that EPA could develop guidance documents to help farmers understand the reporting requirements.

Now, with the passage of the FARM Act, Congress has exempted farmers and ranchers from one of the two laws—CERCLA. Large-scale industrialized farms, however, will still have to report emissions of certain hazardous air pollutants to state and local officials under EPCRA.

Cage-free conundrum

Ammonia emissions in states that produce a lot of eggs, such as Iowa, could soon be on the rise, unless the egg industry take steps to mitigate such releases. That is because of a growing trend in the U.S. to raise egg layers in cage-free housing systems. Cage-free housing allow hens to spread their wings, bathe and scratch in dirt, perch, and walk around inside the chicken house. But there are trade-offs, including reduced air quality.

Cage-free eggs on the rise

The U.S. egg industry is transitioning away from conventional cages. The number of cage-free hens went from 3.5% of all egg layers in 2008 to about 16% today.

Source: USDA Livestock, Poultry & Seed Program

Many restaurant chains, grocery stores, food companies, and food-service providers have committed to use eggs only from cage-free hens by a certain date. Responding to consumer pressure for more humanely raised products, McDonald’s announced in September 2015 that it will use only cage-free eggs by 2025 in its U.S. and Canadian restaurants. A slew of other restaurants and food companies followed with similar pledges. U.S. egg producers are now scrambling to increase the supply of cage-free eggs.

But more cage-free eggs for consumers may mean poorer air to breathe for people living near the chickens. A 2015 study by the Coalition for Sustainable Egg Supply (CSES) showed that raising chickens in cage-free housing leads to higher ammonia and airborne particulate matter levels than raising them in conventional cages (Poult. Sci. 2015, DOI: 10.3382/ps/peu075). The ammonia comes from manure that accumulates in the litter, and particulate matter gets released when the birds bathe in the dust and scratch in the litter. Manure is easily removed using belts under cages, but it accumulates on the floor in the cage-free system.

The CSES project was coordinated by the Center for Food Integrity, a group of animal welfare scientists, academic researchers, food safety advocates, egg suppliers, restaurants, and food retailers, to examine the trade-offs between different commercial egg-production systems. The project examined factors including chicken welfare, air quality, health and safety of workers, food safety and quality, and food cost.

One of the air quality experts involved in the CSES study, Hongwei Xin, an assistant dean for research and director of the Egg Industry Center at Iowa State University, is now examining ways to reduce ammonia and particulate matter emissions from cage-free housing systems.

Spraying a liquid such as electrolyzed water can keep particulate matter out of the air, but liquid spray will increase the moisture content of litter, leading to a rise in ammonia. That problem can be solved by applying an acidic liquid to the litter, but spraying acidic liquid in the chicken house corrodes metal equipment. Xin and colleagues overcame both problems by first applying a commercial poultry-litter treatment, sodium bisulfate, to the litter. They then sprayed neutral electrolyzed water onto the litter daily for 11 days, followed by three days of nonspraying.

The researchers observed a reduction in ammonia levels that was proportional to the amount of poultry-litter treatment added. The highest application (0.9 kg/m2) led to a 79% reduction in ammonia (Trans. ASABE2018, DOI: 10.13031/trans.12481). Similarly, they saw decreases in particulate matter related to increased moisture content from the neutral electrolyzed water spray. The researchers conducted the study in a laboratory that simulated a cage-free housing system. The next step, they say, is to try it in the real world to determine if it is effective and economical.

National farm air study falters

Thanks to Congress passing the FARM Act, EPA now has more time to find a way for farmers to estimate their air emissions, particularly for ammonia and hydrogen sulfide released from animal waste. Should emissions reports become required for all farmers again, the agency believes it would be too expensive and impractical to require 100,000 farms to set up air monitors to get actual measurements of air emissions.

EPA has been wrestling with the problem of estimating emissions from livestock waste since the late 1990s. At that time, EPA claimed it did not have sufficient air emissions data to develop accurate methods for determining whether livestock operations are subject to emissions permit requirements under the Clean Air Act and reporting requirements under CERCLA and EPCRA.

Many factors influence air emissions from animal waste, including the number and types of animals, as well as their life stages. In addition, factors such as geography, environmental conditions, feed additives, and manure management affect air emissions. As a result, farmers cannot accurately estimate emissions using only the numbers and species of animals at their facilities. In some cases, farms with fewer animals will have higher emissions than those with more animals of the same species, EPA notes.

In 2005, the pork, dairy, egg layer, and broiler chicken industries worked out an agreement with EPA to fund a $15 million study to monitor air emissions at farms representing those four sectors across the U.S. A team of researchers led by Purdue University monitored emissions for two years at 24 sites in nine states, near barns and lagoons where waste was stored. They measured ammonia, airborne particulate matter, volatile organic compounds, hydrogen sulfide, and carbon dioxide. They also recorded meteorological data, such as temperature and wind speed, and the number of animals, the type of animal housing, and the waste management practices at the site.

EPA was supposed to use the data to develop models for estimating hazardous air emissions from large-scale animal operations. The monitoring study was completed in 2010, and EPA released draft methods in 2012. The proposed methods covered eight of 36 source and pollutant combinations agreed to in 2005 by the livestock industry and EPA. But the process came to a halt in 2013, when the agency’s scientific advisory board criticized the quality and quantity of EPA’s data. The effort to develop emissions models has languished ever since, and EPA has yet to finalize any methods for estimating emissions from animal waste.

Battle over broilers

Federal requirements aside, some states are trying to get a handle on livestock emissions. Chicken producers in Maryland, for example, are facing the possibility of a statewide monitoring study aimed at collecting emissions data from the broiler industry.

The Delmarva Peninsula on the eastern shore of Delaware, Maryland, and Virginia is home to more than 1,500 family-owned chicken farms that produced 605 million chickens in 2017, according to the Delmarva Poultry Industry (DPI), which represents Delmarva chicken farmers. Those chickens were raised in about 5,000 houses that can collectively hold 138 million chickens at one time, DPI says.


I smelled a wretched, horrible smell standing hundreds and hundreds of yards away.
Cory Booker, U.S. senator, (D-N.J.)

“Chicken growers are concerned about how to measure the emissions, how to report them to the federal government, and the usefulness of the information that is to be reported,” DPI Executive Director Bill Satterfield told lawmakers at the March 8 Senate hearing. They are now breathing a sigh of relief that the FARM Act exempts them from such requirements.

Ammonia concentrations on poultry and egg farms “are at very low levels, and they dissipate rapidly into the air,” Satterfield said. Even so, chicken producers want to control ammonia emissions because if the levels get too high in chicken houses, the birds don’t grow to their full potential and farm income falls, Satterfield said. One way chicken farmers prevent ammonia formation in chicken houses is by keeping moisture levels low. About 20 years ago, the industry changed its watering systems from open pans to a nipple drinker system, Satterfield said. “You have less water going onto the litter, less potential for humid conditions, and less potential for development of ammonia,” he explained.


Additionally, some chicken farmers add acidic products to the bedding material when the birds are not on it to reduce the pH, leading to the formation of water-soluble ammonium instead of gaseous ammonia. Others add supplements to chicken feed to increase the amount of nitrogen used by the bird to grow meat so that less nitrogen comes out in chicken waste.

The Delmarva chicken industry has also been working to minimize nitrogen emissions to improve the quality of the Chesapeake Bay, Sen. Tom Carper (D-Del.) noted at the hearing. Since the late 1990s, farmers in the Chesapeake Bay watershed have had to follow nutrient management plans, which include having their soil tested for nitrogen and phosphorus that can wash into the bay with rain and lead to algae blooms.

Ammonia air emissions also contribute to the amount of nitrogen going into the Chesapeake Bay. EPA estimates that chicken producers contribute about 18,000 metric tons of ammonia each year, or 17% of the bay’s nitrogen load, but a recent report from the Environmental Integrity Project (EIP) suggests that number is closer to 36,000 metric tons.

EIP, a group that advocates for enforcement of environmental regulations, claims that EPA used an outdated emissions factor derived from European-style chicken houses to estimate ammonia emissions from broiler chickens in the Chesapeake Bay states. In Europe, it is more common to replace litter after every flock, whereas in the U.S., litter is usually replaced annually, according to the report. European chickens are also typically smaller and grown in cooler temperatures than U.S. broilers. These factors result in greater ammonia emissions from U.S. broilers than those raised in Europe, the group says.


To resolve the discrepancy, EIP and other environmental groups are urging Maryland lawmakers to pass legislation that would require state officials to conduct an air monitoring study near poultry houses and neighboring communities. After failing to garner enough support to pass the bill last year, state Sen. Richard Madaleno (D) is trying again this year with S.B. 133, the Community Healthy Air Act.

The bill “is a good first step toward tackling the problem,” Abel Russ, EIP attorney and coauthor of the group’s ammonia emissions report, said in a statement. “The proposed Community Healthy Air Act would require the Maryland Department of the Environment to conduct air monitoring near poultry houses to obtain better data on ammonia air pollution,” he said. “With better information we can find effective ways to control this pollution and clean up the bay.” A companion bill (H.B. 26) introduced by Delegate Robbyn Lewis is also gaining interest in the Maryland Assembly.

Farm groups are strongly opposed to the legislation, saying it will cost the state millions of dollars and duplicate efforts that are currently under way by EPA. They successfully fought against it last year, and it is unclear whether lawmakers have enough support to pass the bills this year. Maryland’s legislative session ends April 9.

Balancing interests

At the March 8 U.S. Senate hearing, Sen. Cory Booker (D-N.J.) was sympathetic to the concerns of small-scale farmers such as the chicken producers in Maryland. But he also told a story about his 2016 trip to Duplin County, N.C.—home to about 60,000 people and more than 2 million pigs. There, he witnessed pig waste being stored in huge open-air lagoons and sprayed onto nearby fields.

“I smelled a wretched, horrible smell standing hundreds and hundreds of yards away,” Booker said, noting that residents of the community came to Washington, D.C., that year asking lawmakers for help. They “complained about suffering from serious respiratory problems, such as asthma, and chronic lung disease caused by living near these lagoons and spray fields,” he said.

It’s time to “rebalance the scales,” Booker said, “and get rid of unneeded regulations” like reporting requirements for pasture-based farming. Lawmakers believe the FARM Act does just that. “I hope that between Congress and EPA we can find a path forward that gives clarity to small farmers that they do not need to report their emissions,” he said.

But large-scale industrialized farm animal operations are “a different story” and “create serious health risks,” Booker added. He and other Democrats at the hearing advocated for requiring concentrated animal feeding operations that emit more than 100 pounds (45 kg) of ammonia or hydrogen sulfide per day to report their releases under EPCRA. Because of their concerns, such operations must adhere to EPCRA emissions-reporting requirements. What states may do going forward remains to be seen. Ultimately, “This is about people,” Booker emphasized. “This is about their lives, their livelihoods, their property values, and their health.”


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