Maryland appeals ruling forcing regulation of gaseous ammonia emissions from poultry farms

The Maryland Department of the Environment is appealing a court ruling that would compel the state to regulate gaseous ammonia emissions coming from the poultry farms that dot the Eastern Shore.

A Montgomery County Circuit Court judge had ruled that the state needed to rework water pollution permits to include controls on the gas, which is released from animal waste and pumped out of industrial chicken houses and similar facilities via exhaust fans.


When it ends up in bodies of water like the Chesapeake Bay, ammonia breaks down into nitrogen, a nutrient that can overstimulate the growth of algae and have dire consequences for aquatic life. In the air, it can cause health problems such as asthma attacks, coughing, and nose and throat irritation.

In response to the court ruling, environmental advocates were hopeful MDE would start requiring so-called concentrated animal feeding operations (or CAFOs) to do things like: use poultry litter that mitigates emissions or plant vegetation areas that would block the gas from flowing into waterways.


Under the current permit structure, those things are simply considered best practices. In certain situations, facilities have to spell out what practices they’re using, but they aren’t required to take particular actions to achieve ammonia reductions.

“We hoped they would spend this energy protecting Maryland’s waters and community health, instead of going through the appeals process,” wrote Kathy Phillips, executive director of the Assateague Coastal Trust, which brought the suit with the help of the Chesapeake Legal Alliance.

MDE’s appeal could pave the way for arguments before a higher court or settlement negotiations.

During the proceedings, the state argued that extending the water pollution permit process to include gaseous ammonia would set a confusing precedent. Officials balked at the idea of including a pollutant that travels by air in water regulations.

But Circuit Court Judge Sharon V. Burrell found that Maryland law, an expansion of the federal Clean Water Act, requires MDE to control “any liquid, gaseous, solid, or other substance that will pollute any waters of this State” — including ammonia.

The ruling creates regulatory uncertainty, and could force MDE to require Clean Water Act permits for entities that traditionally only required Clean Air Act permits, said Maryland Secretary of the Environment Ben Grumbles. The judge disagreed.

“We believe the decision is trying to impose a Clean Water permit for a Clean Air Act type of situation,” Grumbles said. “It’s not whether to regulate these animal feeding operations. It’s what’s the right tool under law?”

But concentrated animal feeding operations don’t have to get Clean Air Act permits, which is part of why environmental groups have sought regulation under the Clean Water permit process.


The Delmarva Chicken Association, which spoke out against the court’s March ruling, applauded the state’s attempt to challenge it.

“This appeal is good news for farmers who raise chickens, cows, pigs and other animals,” wrote Holly Porter, the association’s executive director. “We look forward to a fair-minded judicial review of a lone judge’s decision to strike down the ... permit. This appeal will provide an opportunity to correct the unjustified, sudden insertion of air emissions regulations into a water quality permit.”

Maryland’s environmental community has long targeted the issue. Advocates have struggled to win victories in the General Assembly, where they’d asked for ammonia emissions to be closely monitored by the state.

In 2019, Delmarva Poultry and an environmental foundation put up funds to study ammonia emissions near two different poultry farms, a more narrow scope than activists had called for in their bill. MDE is seeking funding to expand the program, Grumbles said.

“We have recognized over the last several years that there are advocates and citizens who have stated: More needs to be done to reduce air emissions from these facilities, and the first step to effective and sustainable and successful regulation is to get more data,” Grumbles said.

The advocates also have won some county-level changes, including in Worcester, where certain types of vegetative buffers must be planted near exhaust fans in the feeding houses. But the court ruling out of Montgomery could result in similar rules for all such farms, grounded in water pollution permits.


“It’s a shame,” Phillips wrote. “And we’re confident that this decision will be upheld.”