Area of Critical Environmental Concern

Areas of Critical Environmental Concern (ACEC) is a conservation ecology program in the western United States, managed by the Bureau of Land Management. The ACEC program was conceived in the 1976 Federal Lands Policy and Management Act (FLPMA), which established the first conservation ecology mandate for the BLM. The FLPMA mandate directs the BLM to protect important riparian corridors, threatened and endangered species habitats, cultural and archeological resources and unique scenic landscapes that the agency assesses as in need of special management attention.

To be considered a potential ACEC an area must meet criteria of both relevance and importance.

An area meets the relevance criteria of an ACEC if it contains one or more of the following:

An area meets the importance criteria if it is characterized by one or more of the following:

(For more detailed descriptions of the following sites see)

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