CALPUFF and CAFOs: Air Pollution Modeling and Environmental Justice Analysis in the North Carolina Hog Industry

Abstract

Concentrated animal feeding operations (CAFOs) produce large amounts of animal waste, which potentially pollutes air, soil and water and affects human health if not appropriately managed. This study uses meteorological and CAFO data and applies an air pollution dispersion model (CALPUFF) to estimate ammonia concentrations at locations downwind of hog CAFOs and to evaluate the disproportionate exposure of children, elderly, whites and minorities to the pollutant. Ammonia is one of the gases emitted by swine CAFOs and could affect human health. Local indicator of spatial autocorrelation (LISA) analysis uses census block demographic data to identify hot spots where both ammonia concentrations and the number of exposed vulnerable population are high. We limit our analysis to one watershed in North Carolina and compare environmental justice issues between 2000 and 2010. Our results show that the average ammonia concentrations in hot spots for 2000 and 2010 were 2.5-3-times higher than the average concentration in the entire watershed. The number of people living in the areas where ammonia concentrations exceeded the minimal risk level was 3647 people in 2000 and 3360 people in 2010. We recommend using air pollution dispersion models in future environmental justice studies to assess the impacts of the CAFOs and to address concerns regarding the health and quality of life of vulnerable populations.

Selecting Data Analytic and Modeling Methods to Support Air Pollution and Environmental Justice Investigations: A Critical Review and Guidance Framework

“…Any model that relies primarily on atmospheric advection–diffusion equations with little atmospheric chemistry is considered a dispersion model. Dispersion models are highly useful for EJ studies because they can model many pollutants, both aerosols and gases, as long as they are not highly chemically reactive. ,,,− There are many examples of dispersion models, but they generally range from simple models that focus on a few point or line sources such as roads (i.e., CALINE, COPERT) to models that are more complex, include more sources, and rely on more complete meteorological data (i.e., AERMOD, CALPUFF). Many of the more complex models can include simplified atmospheric chemistry but are still not appropriate for some reactive air pollutant species.…”

“…Often, EJ is thought of as an urban issue since many sources of air pollution are located in and around cities and towns. However, this is not always the case, and rural communities may experience EJ issues surrounding animal agriculture and industrial emissions, while facing a lack of monitoring . Some of the simplest methods rely on monitor data, and regulatory monitoring networks can be sparse or unstandardized among different governmental areas.…”

Environmental Injustice and Industrial Chicken Farming in Maryland

“…A 2015 study determined that communities with high percentages of Hispanic individuals are disproportionately burdened by CAFOs in Ohio [ 29 ]. Furthermore, various North Carolina studies have determined that vulnerable populations are disproportionately burdened by poor air quality and high ammonia levels as a result of close proximity to CAFOs [ 13 , 30 ].…”

Environmental Injustice and Industrial Chicken Farming in Delaware

“…21 This groundbreaking study sounded the alarm for further research and the beginnings of the environmental justice movement. The environmental justice lens has been previously applied to the hog industry, demonstrating that low-wealth communities and communities of color are more likely to host hog CAFO operations, and therefore are differentially exposed to the industry's deleterious byproducts., 2,4,[22][23][24][25][26] Previous environmental justicefocused research has demonstrated that proximity to CAFOs is associated with increased exposure to airborne pollutants such as ammonia, 24,27 while occupational exposure is associated with pathogens such as fecal waste, Hepatitis E virus, coliphages, and antibiotic-resistant Staphylococcus aureus. [28][29][30][31] To our knowledge, no study has examined environmental justice issues associated with chicken farming in the state of Delaware.…”