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Concentrated Animal Feeding Operations: EPA Needs More Information and a Clearly Defined Strategy to Protect Air and Water Quality from Pollutants of Concern

GAO-08-944 Published: Sep 04, 2008. Publicly Released: Sep 24, 2008.
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Concentrated Animal Feeding Operations (CAFO) are large livestock and poultry operations that raise animals in a confined situation. CAFOs can improve the efficiency of animal production but large amounts of manure produce can, if not properly managed, degrade air and water quality. The Environmental Protection Agency (EPA) is responsible for regulating CAFOs and requires CAFOs that discharge certain pollutants to obtain a permit. This report discusses the (1) trends in CAFOs over the past 30 years, (2) amounts of waste they generate, (3) findings of key research on CAFOs' health and environmental impacts, (4) EPA's progress in developing CAFO air emissions protocols, and (5) effect of recent court decisions on EPA's regulation of CAFO water pollutants. GAO analyzed U.S. Department of Agriculture's (USDA) data from 1982 through 2002, for large farms as a proxy for CAFOs; reviewed studies, EPA documents, laws, and regulations; and obtained the views of federal and state officials.

Because no federal agency collects consistent, reliable data on CAFOs, GAO could not determine the trends in these operations over the past 30 years. However, using USDA data for large farms that raise animals as a proxy for CAFOs, it appears that the number of these operations increased by about 230 percent, going from about 3,600 in 1982 to almost 12,000 in 2002. Also, during this 20-year period the number of animals per farm had increased, although it varied by animal type. Moreover, GAO found that EPA does not have comprehensive, accurate information on the number of permitted CAFOs nationwide. As a result, EPA does not have the information it needs to effectively regulate these CAFOs. EPA is currently working with the states to establish a new national data system. The amount of manure generated by large farms that raise animals depends on the type and number of animals raised, but large operations can produce more than 1.6 million tons of manure a year. Some large farms that raise animals can generate more raw waste than the populations of some U.S. cities produce annually. In addition, according to some agricultural experts, the clustering of large operations in certain geographic areas may result in large amounts of manure that cannot be effectively used as fertilizer on adjacent cropland and could increase the potential of pollutants reaching nearby waters and degrading water quality. Since 2002, at least 68 government-sponsored or peer-reviewed studies have been completed that examined air and water quality issues associated with animal feeding operations and 15 have directly linked air and water pollutants from animal waste to specific health or environmental impacts. EPA has not yet assessed the extent to which these pollutants may be impairing human health and the environment because it lacks key data on the amount of pollutants that are being emitted from animal feeding operations. As a first step in developing air emissions protocols for animal feeding operations, in 2007, a 2-year nationwide air emissions monitoring study, largely funded by industry, was initiated. However, as currently structured, the study may not provide the scientific and statistically valid data it was intended to provide and that EPA needs to develop air emissions protocols. Furthermore, EPA has not established a strategy or timetable for developing a more sophisticated process-based model that considers the interaction and implications of all emission sources at an animal feeding operation. Two recent federal court decisions have affected EPA's ability to regulate water pollutants discharged by CAFOs. The 2005 Waterkeeper case required EPA to abandon the approach that it had proposed in 2003 for regulating CAFO water discharges. Similarly, the 2006 Rapanos case has complicated EPA's enforcement of CAFO discharges because EPA believes that it must now gather significantly more evidence to establish which waters are subject to the Clean Water Act's permitting requirements.


Recommendations for Executive Action

Agency Affected Recommendation Status
Environmental Protection Agency In order to more effectively monitor and regulate CAFOs, the Administrator of the Environmental Protection Agency should complete the agency's effort to develop a national inventory of permitted CAFOs and incorporate appropriate internal controls to ensure the quality of the data.
Closed – Implemented
On July 20, 2012, EPA withdrew its proposal that would have required information to be submitted to the EPA about concentrated animal feeding operations (CAFOs). The agency will instead use existing federal, state and local sources of information to gather data about CAFOs and help ensure that CAFOs are implementing practices that protect water quality. EPA sought public comment on the 2011 proposal and is making the decision to withdraw it in light of comments received from states regarding the amount of information states already have and include as part of the CAFO permitting process. In July, EPA signed a memorandum of understanding with the Association of the Clean Water Administrators (ACWA) to facilitate the exchange of information. This collaborative effort between the EPA and ACWA will focus on identifying CAFOs and obtaining pertinent information about CAFOs on a state-by-state basis for use by both ACWA members and the EPA.
Environmental Protection Agency In order to more effectively determine the extent of air emissions from animal feeding operations, the Administrator of the Environmental Protection Agency should reassess the current data collection efforts, including its internal controls, to ensure that the National Air Emissions Monitoring Study will provide the scientific and statistically valid data that EPA needs for developing its air emissions protocols.
Closed – Implemented
According to EPA, the agency took a systematic approach to evaluating and reviewing the 2-year data collection phase of the National Air Emissions Monitoring Study. The agency noted that it implemented a quality assurance plan and conducted audits of its monitoring sites to ensure that the data was being collected in accordance with the quality assurance plan. The agency also noted that fewer findings were made during the second year of audits than in the first. EPA's data collection effort ended in early 2010
Environmental Protection Agency In order to more effectively determine the extent of air emissions from animal feeding operations, the Administrator of the Environmental Protection Agency should provide stakeholders with information on the additional data that it plans to use to supplement the National Air Emissions Monitoring Study.
Closed – Implemented
In the March 13, 2012 Federal Register, the EPA announced the availability of two draft documents related to the development of emission estimating methodologies (EEMs) for broilers animal feeding operations (AFO) and lagoons and basins for swine and dairy animal feeding operations. These documents were available for public review and the comment period ended on June 11, 2012. Also, in August 2011, the EPA's Office of Air and Radiation (OAR) requested the Science Advisory Board (SAB) to review the draft EEMs. In response to OAR's request, the SAB formed the Animal Feeding Operation Panel that is comprised of nationally recognized experts with demonstrated expertise and experience in air emissions from AFOs; air monitoring and detection methods; exposure assessment; environmental statistics; emission and statistical modeling; and uncertainty analysis. The SAB panel held a public meeting on March 14-16, 2012 to review the draft documents. Data submitted in response to the agency's January 2011 Call for Information and data identified during the agency's literature search were listed in the draft documents along with the agency's assessment of the data. The EPA is reviewing additional data submitted during the public review period for the two draft documents; by the SAB panel during the March 2012 meeting; and public comments submitted to the SAB.
Environmental Protection Agency In order to more effectively determine the extent of air emissions from animal feeding operations, the Administrator of the Environmental Protection Agency should establish a strategy and timetable for developing a process-based model that will provide more sophisticated air emissions estimating methodologies for animal feeding operations.
Closed – Not Implemented
According to EPA, its first step toward developing a process-based model was to complete the National Air Emissions Monitoring Study (NAEMS). The agency is developing a plan for estimating AFO emissions. Additional analyses of its existing data set is necessary to demonstrate that the current data set plus other relevant available data sets are representative and provide an adequate basis for estimating emissions for other farms that are not in the current datasets. Following completion of this effort over the next 18-36 months, EPA, in conjunction with USDA, will work to understand the latest science related to process-based models for each AFO sector and determine what additional research might be needed to further develop and validate results generated by these models.

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