Gases and liquids produced by decomposing organic agricultural materials – from livestock feeding, agricultural waste, food processing and other sources – represent huge and growing problems. Unchecked, they produce:
- Greenhouse gases, primarily methane
- Excess phosphates and nitrates in soil and ground and surface water
- Pathogens, including e. coli
- Odor
More than 1.37 billion tons of animal waste is produced in the U.S. each year. This amount is 130x as much as the human waste produced, and is equal to 5 tons of animal waste per human resident.
The U.S. Environmental Protection Agency says one dairy farm with 2,500 cows produces as much biowaste as a city with around 411,000 residents. However, despite this magnitude, animal waste is not processed like human sewage, and there is very little regulation of animal waste disposal.
Currently, these wastes are stored in large, open “lagoons,” or in open mounds on the ground. As decomposition takes place, methane is released and remains in the atmosphere for at least 10 years. Methane is 21x more powerful than carbon dioxide at absorbing atmospheric energy, contributing to climate change worldwide.
Storage lagoons are also subject to leaking, and in areas with severe weather (such as hurricanes and flooding), open lagoons can be breached and spread liquids and solids over large areas.
According to the Pew Commission on Industrial Farm Animal Production:
The EPA says that pollutants from animal waste can result in fish kills and reduced biodiversity and that nitrogen and phosphorus pollution can contribute to algae blooms, which can then lead to a number of negative health effects in animals and humans.
Human and animal health can also be harmed by the pathogens and nitrogen in animal waste. Nitrogen in manure is easily transformed into nitrates. The EPA found that nitrates are the most widespread agricultural contaminant in drinking water wells and estimates that 4.5 million people are exposed to elevated nitrate levels from drinking water wells. Nitrates, if they find their way into the groundwater, can potentially be fatal to infants.