Classification of Aquatic Environments

Section 364 Section 364.207  Classification of Aquatic Environments Aquatic environments are classified according to the following: a)         Balanced environment:  Intolerant organisms are many in number and species, or more in numbers than other forms present. Intolerant present >50% Moderate, facultative and tolerant usually present < 50% b)         Unbalanced environment:  Intolerant organisms are less in number than other forms combined, but combined with moderate forms, they usually outnumber tolerant forms. Intolerant present < 50% but >10% Moderate, facultative and tolerant usually present > 50% c)         Semi-polluted environment:  Intolerant organisms are few or may not be present.  Moderate and/or facultative organisms present. Intolerant present >10% Moderate, facultative and tolerant usually present > 90% d)         Polluted environment: 1)         Intolerant organisms absent, only tolerant organisms present or no organisms present. Tolerant present = 100% 2)         Organisms which are not adapted to inhabit a polluted environment are occasionally collected as a result of factors produced by the drift and are not representative.