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Section 404 of the Clean Water Act

Field Operations Manual for Assessing the Hydrologic Permanence and Ecological Condition of Headwater Streams

The purposes of this manual are to: 1) document procedures that were developed and used by the United States Environmental Protection Agency’s (USEPA) Ecosystem Exposure Research Division (EERD) for the assessment of the physical and biological characteristics of headwater streams; and 2) provide a catalog of procedures to other groups with an interest in headwater stream assessment.

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