Stressor Identification Guidance Document
The process has three main steps: (1) List candidate causes of impairment, (2) analyze the evidence, and (3) characterize the causes. When evidence is adequate, using this guidance, investigators should be able to successfully identify the likely cause, or causes. This guidance will also help investigators identify where evidence is weak or lacking and needs to be developed to be able to successfully identify the stressor(s). Once the causes of the biological impairments are identified, water resource managers will be better able to locate the sources of the stressor, or stressors, and take management actions aimed at improving the biological condition of the water body.
This guidance is advisory in nature and its use is not mandatory. As such this guidance does not impose legally-binding requirements on EPA, the States, Tribes, industry, the public or any other entity.
This document has been reviewed in accordance with U.S. Environmental Protection Agency policy and approved for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.