Citation:

Rumsey, I. Development of Draft Emission Estimating Methodologies for Animal Feeding Operations: Process Overview. Waste to Worth Conference, Virtual, Virtual, April 20, 2022.

Impact/Purpose:

Animal feeding operations (AFOs) are agricultural operations where animals are kept and raised in confined areas. Changes within the animal agriculture industry over recent decades has resulted in fewer but larger AFOs that are also more geographically concentrated. AFOs and the associated waste management practices (e.g., manure handling) emit various pollutants into the atmosphere including ammonia (NH3), hydrogen sulfide (H2S), volatile organic compounds (VOCs) and particulate matter (PM). Thus, there are concerns regarding these facilities due to the potential impact these compounds can have on human health and the environment. Air emissions from AFOs are not regulated by any AFO specific standards within the Clean Air Act (CAA), but AFOs could emit air pollutants in sufficient quantity to trigger certain general CAA permit requirements. Key to making this determination are reliable methods by which emissions can be estimated from the complex processes at these facilities. As such, the Office of Research and Development (ORD) is working with partners in the Office of Air Quality Planning and Standards (OAQPS) to develop Emissions Estimation Methodologies (EEMs) which can be used to determine farm-scale emissions for the purpose of determining CAA permitting applicability. These EEMs are based on statistical models developed using data from the National Air Emissions Monitoring Study (NAEMS).

Description:

This product is being presented to a conference audience as the second part of a three-part panel session on NAEMS and EEM Development. Panel organizers requested that I put together a presentation on the EEM method development process. The first panelist will provide an overview of the measurements and data collection (i.e., NAEMS) and the third panelist will discuss EEM reports, uses and limitations of EEMs and future plans. This presentation provides an overview of the EEM development process which involves several steps including the selection of variables for further investigation and model selection, the approaches for developing and evaluating the daily emission model, model application and additional testing, and the approach for determining annual emissions and associated uncertainty. The EEM development process is described in more detail in the draft EEM reports, which can be found at https://www.epa.gov/afos-air/draft-air-emissions-estimating-methodologies-animal-feeding-operations#naems-uem-2020 

Record Details: