| Amine | (Environmental Engineering) A functional group consisting of "-NH2." |
| Amino acid | (Environmental Engineering) A functional group which consists of a carbon with a carboxylic acid, "-COOH" and an amine, "-NH2." These compounds are the building blocks for proteins. |
| Anabolism | (Environmental Engineering) Biosynthesis, the production of new cellular materials from other organic or inorganic chemicals. |
| Autotrophic | (Environmental Engineering) Organisms which utilize inorganic carbon for synthesis of protoplasm. Ecologists narrow the definition further by requiring that autotrophs obtain their energy from the sun. In microbiologist parlance, this would be a photoautotroph. See photoautotrophic and chemoautotrophic. |
| Autotrophs | (Environmental Engineering) A group of organisms capable of obtaining carbon for synthesis from inorganic carbon sources such as carbon dioxide and its dissolved species (the carbonates). This group includes plants and algae. |
| Biosynthesis | (Environmental Engineering) Catabolism, the production of new cellular materials from other organic or inorganic chemicals. |
| Cell | (Environmental Engineering) A unit of varying dimensions in a landfill which is isolated from the environment by 6 to 12 inches of soil cover. A cell is one day's waste or less. A cell is covered with soil at the end of each day. |
| Chemical oxygen demand (COD) | (Environmental Engineering) The amount of oxygen required to oxidize any organic matter in the water using harsh chemical conditions. |
| Chemoautotrophic | (Environmental Engineering) Organisms which utilize inorganic carbon (carbon dioxide or carbonates) for synthesis and inorganic chemicals for energy. See autotrophic and photoautotrophic. |
| Chlorofluorocarbons | (Environmental Engineering) Synthetic organic compounds used for refrigerants, aerosol propellants (prohibited in the U.S.), and blowing agents in plastic foams. CFCs migrate to the upper atmosphere destroying ozone and increasing global warming. Typical atmospheric residence times are 50 to 200 years. |