Livestock emissions still up in the air

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.

“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.”