Two stage lagoons consist of two holding areas. The first receives the waste from the barn and allows the solids to settle out. The second receives the overflow from the first stage. Multiple stage lagoons add more overflow areas. There are two types of lagoon systems.
Aerobic lagoon require oxygen for the microorganisms to live.
Anaerobic lagoon do not require oxygen for the microoganism. Odor from aerobic lagoons is low, but the cost to install and operate the system can be high. Therefore there are very few aerobic lagoons in Minnesota. During microbial decomposition in an anaerobic lagoon many compounds are produced. The most notable are carbon dioxide, methane, ammonia and hydrogen sulfide.