	Introduction

The animal sector of agriculture has undergone major changes in the last several decades, a fact that has drawn the attention of policymakers and the public. In particular, organizational changes within the industry to enhance economic efficiency have resulted in larger confined production facilities that often are geographically concentrated. Increased facility size and regional concentration of livestock and poultry operations have, in turn, given rise to concerns over the management of animal wastes from these facilities and potential impacts on environmental quality, public health and welfare. Federal environmental law does not regulate all agricultural activities. Still, certain large animal feeding operations (AFOs) where animals are kept and raised in confinement are subject to environmental regulation. Some livestock operations also may be subject to requirements of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, the Superfund law) and the Emergency Planning and Community Right-to-Know Act (EPCRA). The issue of applicability of these laws to livestock and poultry operations—especially CERCLA and EPCRA—has been controversial and has drawn congressional attention. 2997 and S. 1729 ). §§11001-11050) have reporting requirements that are triggered when specified quantities of certain substances are released to the environment. In addition to reporting requirements, CERCLA includes provisions authorizing federal cleanup of releases of hazardous substances, pollutants, or contaminants that may present an imminent and substantial danger to the public health or welfare (§104), and imposing strict liability for cleanup and damages for injury to, destruction of, or loss of natural resources resulting from releases of hazardous substances (§107). The citizen suit provisions have been used to sue poultry producers and swine operations for violations of the laws. In two cases, environmental advocates claimed that AFO operators had failed to report ammonia emissions, putting them in violation of CERCLA and EPCRA. In both cases, federal courts supported broad interpretation of key terms defining applicability of the laws' reporting requirements to livestock operations. The ruling was not appealed. EPA was not a party in either of these lawsuits. Three other cases in federal courts, while they did not include reporting violations, also have drawn attention, in part because they raised the question of whether animal wastes that contain phosphorus are hazardous substances that can create cleanup and natural resource injury liability under CERCLA. The exemption would apply to releases to the air from manure, digestive emissions, and urea, including animal waste mixed with bedding, compost, and other specified materials. The court approved the government's request in October 2010. Congressional Interest

The court cases testing the applicability of CERCLA and EPCRA to poultry and livestock operations led to congressional interest in these issues. Also in November 2005, legislation was introduced in the 109 th Congress to amend CERCLA to clarify that manure is not a hazardous substance, pollutant, or contaminant under that act and that CERCLA's notification requirements would not apply to releases of manure ( H.R. Enacting an exemption would severely hamper the ability of government to appropriately respond to releases of hazardous substances and pollution caused by an animal agriculture operation, they argued.
The animal sector of agriculture has undergone major changes in the last several decades: organizational changes within the industry to enhance economic efficiency have resulted in larger confined production facilities that often are geographically concentrated. These changes, in turn, have given rise to concerns over the management of animal wastes and potential impacts on environmental quality.
Federal environmental law does not regulate all agricultural activities, but certain large animal feeding operations (AFOs) where animals are housed and raised in confinement are subject to regulation. The issue of applicability of these laws to livestock and poultry operations—especially the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, the Superfund law) and the Emergency Planning and Community Right-to-Know Act (EPCRA)—has been controversial and has drawn congressional attention.
Both CERCLA and EPCRA have reporting requirements that are triggered when specified quantities of certain substances are released to the environment. In addition, CERCLA authorizes federal cleanup of releases of hazardous substances, pollutants, or contaminants and imposes strict liability for cleanup and injuries to natural resources from releases of hazardous substances.
CERCLA and EPCRA include citizen suit provisions that have been used to sue poultry producers and swine operations for violations of those laws. In two cases, environmental advocates claimed that AFO operators had failed to report ammonia emissions, in violation of CERCLA and EPCRA. In both cases, federal courts supported broad interpretation of key terms defining applicability of the laws' reporting requirements. Three other cases not dealing with reporting violations also have attracted attention, in part because of questions of whether animal wastes contain hazardous substances that can create cleanup and natural resource damage liability under CERCLA.
In 2008, EPA issued a rule to exempt animal waste emissions to the air from most CERCLA and EPCRA reporting requirements. Legal challenges to the rule followed. In 2010, a federal court approved the government's request to voluntarily remand the rule to EPA for reconsideration and possible modification, but the agency has not yet proposed a new or revised rule or taken other action following the remand. Litigation challenging the exemption rule was restarted in 2015.
The lawsuits testing the applicability of CERCLA and EPCRA to poultry and livestock operations and potential changes by EPA to the 2008 exemption rule have led to congressional interest in these issues. In the 112th Congress, legislation was introduced that would amend CERCLA to clarify that manure is not a hazardous substance, pollutant, or contaminant under that act and that the notification requirements of both laws would not apply to releases of manure (H.R. 2997 and S. 1729). Proponents argued that Congress did not intend that either of these laws apply to agriculture and that enforcement and regulatory mechanisms under other laws are adequate to address environmental releases from animal agriculture. Opponents respond that enacting an exemption would severely hamper the ability of government and citizens to know about and respond to releases of hazardous substances caused by an animal agriculture operation. Similar legislation has not been introduced subsequently.