Manure System Type

Description

Aerobic lagoon

Aerobic lagoons are typically uncovered earthen basins storing liquid or otherwise wet manure slurry, in which the manure is aerated to maximize biological oxidation of manure solids. Emissions are assessed for lagoons with natural and forced aeration.

Anaerobic digester

Anaerobic digesters are closed manure treatment systems designed to maximize conversion of organic wastes into biogas. These can range from covered anaerobic lagoons to highly engineered systems. Methane gas leakage is the main source of GHG emissions; very little nitrous oxide gas is generated. 

Anaerobic lagoon

Anaerobic lagoons are earthen basins for anaerobic digestion and storage of animal waste. Lagoons may be covered, uncovered with a crust, or uncovered without a crust.

Composting

Composting involves the controlled aerobic decomposition of organic material and can occur in different forms. The tool estimates emissions from composting in vessels, static piles, intensive windrows, and passive windrows.

Runoff holding pond

Holding ponds are usually clay-lined earthen structures that store liquid runoff from feeding operations. They are commonly emptied using irrigation equipment.

Solid storage

Solid manure (80% or less moisture and 20% or more solids) can be assessed as stockpiles, covered or compacted, as a bulking agent, or as additives.

Storage tanks

Storage tanks and liquid/slurry storage ponds typically store slurry or wastewater that was scraped or pumped from housing systems. The tool estimates emissions from storage tanks that are covered, uncovered with a crust, and uncovered without a crust.

Land applied/removed offsite

Manure is removed from the animal agriculture “entity” and may be applied offsite, such as on a cropland field.