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Special Management

ACECs and Other Forms of Special Management Areas

Wilderness Study Areas and Wilderness Areas:

ACECs are special management areas that, unlike wilderness areas , are designated by administrative action via resource management plans (RMP). Wilderness study areas are administrative units identified and designated as required under Federal Land Management and Policy Act of 1976 (FLMPA). Wilderness study areas could only be designated prior to 1991. Such units remain under administrative protection until those areas are designated by Congress as wilderness areas, become some other national landmark (ex. National Monument), or are released back into the public domain. ACECs can be designated by an individual BLM field office through an RMP after determining whether the units meet the relevance and importance criteria.

ACECs may be designated within wilderness study areas and wilderness areas if the relavence and importance criteria are met. An RMP or plan amendment provides a clear description of the relationship of ACECs to the recommendations for wilderness study areas. That relationship shall be described to the level of detail required to avoid misunderstanding or misinterpretion. The highest level of protections identified for an area will be followed until Congress makes a determination on a wilderness study area.

Types of ACECs*

Though most ACECs are designated to help protect their natural resources: rare plants, scientific artifacts and scenic quality. The BLM, in concert with other agencies, created subsets of ACECs to showcase/explore their cultural, scenic, and scientific resources. These include:

Outstanding Natural Areas (ONA):

ONAs are congressionally-designated areas that contain unusual or scenic characteristics that deserve national attention. Many of these ACECs are managed primarily for scenic and recreational purposes.

Research Natural Areas (RNA):

RNAs are administrative units under the BLM"s jurisdiction that contain natural resources of significant scientific interest and are managed primarily for research and educational purposes. Such sites are managed to maximize scientific inquiry while minimizing human disturbance.

To become eligible for RNA status an area must contain one or more of the following characteristics:

(1) be a typical representation of a common plant or animal associated; 
(2) an unusual plant or animal association; 
(3) a threatened or endangered plant or animal species; 
(4) a typical representation of common geology, soil, or water feature; or 
(5) an outstanding or usual geologic, soil, or water feature.

RNAs may be designated separately from ACEC status, or as part of an ACEC or other special management area designation. Such sites include paleontological dinosaur fossil beds, rare or endangered species sites, or atypical geological wonders. RNAs are also managed by other federal land management agencies, including the U.S. Forest Service (USFS) , which has been managing their own RNA program for more than 100 years. 

Natural Hazard Areas (NHA):

NHAs are areas that contain natural hazards that, if left unchecked, would significantly endanger human life, health or property. Public use within such areas is restricted to protect the public.

National Natural Landmarks (NNL):

NNLs are administrative units under the National Park Service's National Natural Landmarks Program (NNL). Such areas tend to be designated on public and private lands for conservational purposes, with the owner's consent. Many NNLs on BLM lands are also ACECs. Such areas are usually designated to best exemplify examples of biological and geological features. 

Natural Areas (NA):

NAs are conservation easements under the Colorado Parks and Wildlife's Colorado Natural Areas Program (CNAP). These sites preserve some of the finest examples of Colorado’s original and unique landscapes for the benefit of present and future generations. Many NAs are also ACECs and, as such, CNAP helps coordinate activities such as recreation and education with the BLM.   

*Some of these descriptions are rarely used in the BLM's formal land use planning, but may be found in existing land management plans only in relation or adjacent to BLM ACECs.