Manure Management For Climate Change Mitigation: Regulating Cafo Greenhouse Gas Emissions Under The Clean Air Act

Generated Summary

This document is a journal article that analyzes the potential for regulating Concentrated Animal Feeding Operations (CAFOs) under the Clean Air Act (CAA) to mitigate greenhouse gas (GHG) emissions. The study explores the existing regulatory framework governing CAFOs and greenhouse gas emissions, focusing on the EPA’s authority to regulate these emissions under the CAA. The research examines the feasibility of utilizing existing CAA provisions, specifically those outlined in sections 108, 109, and 111, to establish national emission standards for CAFOs. The study reviews the challenges and opportunities in implementing these regulations, including the implications of the Air Compliance Agreement and the potential impacts of various mitigation strategies, such as digesters and changes in manure management practices, on the livestock industry. The scope includes the intersection of animal agriculture, climate change, and environmental regulations within the United States, proposing a strategic approach to curb GHG emissions from the livestock sector.

Key Findings & Statistics

• Methane and nitrous oxide are the two most abundant non-carbon dioxide greenhouse gases.
• In the United States, agriculture is responsible for about 80% of nitrous oxide emissions and about 35% of methane emissions.
• The largest source of agricultural greenhouse gas emissions stems from the excretions of animals in the livestock industry.
• Enteric fermentation is responsible for 32% of all agricultural emissions and 25% of methane emissions in the United States.
• Manure management activities release nitrous oxide and methane in quantities that total 16% of total United States agricultural emissions.
• In 2016, the total agricultural emissions of primarily carbon dioxide, nitrous oxide, and methane in the United States amounted to about 560 million metric tons of carbon dioxide equivalent.
• According to the EPA’s national greenhouse gas emissions annual inventory, agriculture represents 8.6% of the nation’s total greenhouse gas emissions and 76.7% of its nitrous oxide emissions.
• Methane and nitrous oxide compose 10% and 6%, respectively, of total greenhouse gas emissions in the United States.
• Cows and sheep are the highest produced ruminants in the United States.
• The global warming potential of methane is 28-36 times that of carbon dioxide over a 100-year frame.
• The atmospheric lifespan of methane and nitrous oxide is about 12 years and about 114 years respectively, compared to the 20–200 year lifespan of carbon dioxide.
• There are more than 18,000 CAFOs and 450,000 AFOs in the United States.
• The EPA has the authority to regulate ammonia as a precursor to particulate matter.
• One dairy farm with 2,500 cows produces as much waste as a city with around 411,000 residents.
• In 2016, the total agricultural emissions of primarily carbon dioxide, nitrous oxide, and methane in the United States amounted to about 560 million metric tons of carbon dioxide equivalent.

Other Important Findings

• The EPA can use the existing CAA provisions to regulate CAFO emissions of methane and nitrous oxide, ultimately creating a national framework by setting an emission threshold for all CAFO facilities nationwide.
• The EPA is empowered to use the CAA to regulate greenhouse gases, and has classified methane and nitrous oxide as pollutants.
• Section 111 of the CAA, which focuses on individual source standards, offers the most complete answer to the CAFO greenhouse gas emissions problem.
• The EPA’s authority to regulate greenhouse gases under 111(d) has come under scrutiny, and the agency’s only effort to regulate greenhouse gas emissions under the ESPS program is reflected in its proposed rules for power plants.
• Regulating CAFOs under section 111(b) and (d) would give the CAA maximum regulatory effect because it would allow the regulation of both existing and new sources of greenhouse gas pollution directly.
• The EPA has broad discretion to determine and revise source categories of pollution.
• The EPA’s Air Compliance Agreement provided a “sweeping liability shield for violations of environmental laws,” which made regulation of CAFOs who signed the agreement impossible.
• The EPA should list CAFOs as a regulated category under section 111 not only because methane and nitrous oxide emissions endanger public health and welfare, but also because similar sources are already regulated.
• The EPA’s current interpretation of section 111(d) supports the regulation of greenhouse gas emissions from source categories.

Limitations Noted in the Document

• The study acknowledges that explicit federal regulation aimed at protecting environmental quality from CAFO production only concerns the facilities’ impacts on water resources, thereby limiting the scope of the assessment.
• The reliance on regional concentrations of pollutants for setting limits under the NAAQS/SIPs program poses a challenge for greenhouse gas regulations.
• The article notes that the EPA’s Air Compliance Agreement with CAFOs created an immunity rather than an exemption, potentially limiting the enforcement of regulations.
• The study also notes the difficulty in obtaining sufficient data to establish accurate emission thresholds for CAFOs, as stated by the EPA.
• The article acknowledges the lack of formalized regulations specifically addressing CAFO emissions of methane and nitrous oxide.

Conclusion

The study underscores the critical need for regulating CAFO emissions to address climate change, emphasizing that emissions from both enteric fermentation and manure must be addressed at a national level. The article identifies the EPA’s authority to regulate greenhouse gases under the CAA, particularly sections 108, 109, and 111, and suggests that section 111, which focuses on performance standards for individual sources, is the most effective approach. The document highlights the potential benefits of utilizing existing CAA provisions to regulate CAFO emissions, thereby establishing a national framework with emission thresholds. The limitations within the current regulatory landscape and the historical resistance to regulating the agricultural sector are also discussed. The EPA has the power through the CAA to implement a national greenhouse gas emission threshold for the animal agriculture industry, ensuring compliance by all CAFOs in the United States. However, the study notes that because the EPA’s power to regulate and enforce has been limited by the fact that it “may not be able to enforce regulations unless there was a criminal violation.” Furthermore, the article acknowledges the importance of addressing manure management practices to diminish methane and nitrous oxide emissions. The document explores the potential of various solutions, such as digesters, but highlights the limitations and the potential need for broader policy changes, including possibly decreasing the size of CAFOs and influencing consumer preferences for plant-based diets. In conclusion, the study recognizes the complex interplay of factors, including political considerations, industry practices, and the need for innovative strategies to mitigate climate change. It emphasizes the urgency of regulatory action and the importance of considering multifaceted approaches to reduce greenhouse gas emissions within the animal agriculture industry. The success of these efforts ultimately depends on a combination of regulatory frameworks, technological innovations, and shifts in industry practices and consumer behavior to create the most effective path forward.