DAIRY AND AGRICULTURE INDUSTRY
USEPA Flux Chamber Used to Measure Area Source Emissions from Dry Lot and Flushed Lane Dairies, Poultry Facilities, Land-Applied Manure on Cropland, and Other Agricultural/Animal Husbandry Applications
Air emissions from the agriculture industry in Southern and Central California (dairy farms, egg ranches, manure drying beds, manure treatment, manure composting), has become a focus of regulatory interest. We have been conducting air emission assessments using the USEPA flux chamber technology in California for various regulatory and agricultural interests, in particular California dairies, for over 15 years. The primary focus has been with regard to ammonia, hydrocarbon compound, and odor emissions.
More recently, the focus has been on dairies in the Central Valley with regard to total photo-reactive hydrocarbon compound emissions, or ozone precursors, as related to the ozone non-attainment status in the Valley, and greenhouse gas emissions. Central Valley dairies are typically large (>1,000 head), flush-lane dairies complete with highly engineered manure removal and treatment systems, and well controlled feeding operations.
Virtually all of the area sources on a flushed-lane dairy can be studied using the USEPA flux chamber technology, including: corrals (photo 1), covered barns (beds), bunker feed lanes (photo 2), flushed lanes (photo 3), liquid waste channels, milk parlor effluent storage ponds, liquid waste treatment lagoons (photo 4), manure stock piles (photo 5), drying beds, silage storage piles (photo 6), separator solid storage (photo 7), bedding storage, and feed amendment storage.
While other research teams have focused on enteric animal air emissions (both ends of the cow), our research has focused on emissions of area sources found at dairies. Much of the earlier research had to do with understanding the gross magnitude of air emissions from sources at dairies, unit process emission factors, and total dairy site emissions. But also included in these studies has been the comprehensive characterization of air emission compounds which resulted in a narrowing down of the many compounds of concern based on the compound abundance and impact to the environment. Ultimately, most of the research has focused on ozone precursor emissions and ammonia with some interest in greenhouse gas emissions.
The research also included air emissions from silage crops irrigated with treated wastewater from the dairy, and the emissions of compounds that have the potential for adverse health effects. Non-dairy studies have typically involved animal waste treatment including microbial degradation of liquid wastes, solid waste drying (photo 8), and manure composting.
Photo 1- Measuring VOC and Ammonia Emissions from Dairy Cow Corral
Photo 2- Measuring Time-Dependent VOC Flux from Total Mix Ration (Cattle Feed) in Feed Lanes
Photo 3- Measuring VOC and Ammonia Emissions from Flushed Lane at Dairy
Photo 4- Flux Measurement on Dairy Lagoon
Photo 5- Flux Measurement on Dairy Manure in Corral
Photo 6- Flux Measurement on Silage at Dairy
Photo 7- Flux Measurement from Separator Solids at a Dairy
Photo 8- Emission Measurement on Dairy Manure Applied to Crop Land