a Crop residues, normally recycled to land.
b Animal manure, normally recycled to land. Not including emissions from free-ranging animals.
c Values in parentheses are emissions or consumption ( - ) from energy recovery. These values are not included in totals.
d Metal ore mining in the United States.
e Nonmetallic mineral mining in United States, excluding alumina and phosphate concentration wastes.
f Coal mining, not including coke-oven emissions.
g Petroleum and gas drilling.
h Including natural gas processing and transmission. H2O, CO2, and O2 emissions (consumption) based on combustion of process wastes for energy.
i Process wastes of the organic chemical sector are partly combustible and partly incombustible. Detailed breakdown not available.
j Iron and steel slag are by-products with many uses. concentration wastes are included with the mining sector.
k CO2 emissions are included with fuel combustion
NOTES: Plus ( + ) signs refer to production. Minus ( - ) signs refer to consumption. VOC = volatile organic chemical.