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About the Program
Biocriteria Links
Key Activities
Technical Guidance on Identifying Stressors and Causes of Biological Impairment
In some situations, States and Tribes may identify aquatic life use impairments by analyzing bioassessment data. Where impairments are found in water bodies with only one source of pollution, identifying the cause is straightforward. However, in many water bodies there may be numerous potential causes of biological impairment. Investigating and diagnosing the primary source of the impairment or the relative contribution of all sources can be challenging. EPA will assist the States and Tribes in identifying causes of biological impairment in complex water bodies (those with more than one source of impairment).
EPA will develop technical guidance documents on the identification of stressors once biological impairment is determined. Two documents will be produced:
- A Common Sense, Pragmatic Approach to Diagnosing Stressors
- Scientific Investigations for Identifying Complex Mixtures of Stressors
Uses of Bioassessment Data and Biocriteria: Identifying Stressors and Deciding Actions