Although the values of concern vary by area and ACEC, the effects of key management (i.e., ROWs, CTTM, VRM, and mineral development) on these values and other resource uses would have some similarities. The following paragraphs describe the general effects of key management.
Restrictions on the exploration for or development of mineral resources in an area designated as an ACEC would generally result in adverse impacts to minerals. Withdrawing or closing an area designated as an ACEC to mineral or oil and gas development removes the potential to develop that resource. NSO, CSU, and TLS restrictions and limitations, or restrictions on surface-disturbing activities in ACECs can limit potential development, increase timeframes and costs, and may decrease the feasibility of economic recovery of mineral resources. Within an area designated as an ACEC, the BLM would require a plan of operations for all locatable mineral exploration (except casual use) and development, including disturbances of 5 acres or less (43 CFR 3809). The BLM would not automatically require a plan of operations absent such a designation (see Section 4.2.1 Locatable Minerals for more information). In parts of ACECs with low development or potential, the adverse impacts of such restrictions and stipulations generally would be lower because the resource is either not present in commercial quantities or is uneconomical to mine.
Closing an area to mineral development or applying other restrictions or mitigation to minerals development generally results in beneficial impacts to scenic quality, vegetation, soils, wildlife habitat, cultural resources, and other values of concern in ACECs by protecting the identified important and relevant resources from disturbance or degradation.
Impacts from ROW management in ACECs and other Management Areas generally affects the ROW program and the values of concern for the ACEC. Managing an area with more ROW restrictions, such as ROW avoidance/mitigation areas, generally would require additional mitigation, application of BMPs, or other design considerations that would result in adverse impacts to ROWs in the form of additional expense and delay of project development. Restrictions, limitations, or required mitigation for ROW authorizations generally result in beneficial impacts to the values of concern in ACECs by protecting these resources from disturbance or mitigating adverse impacts to an acceptable level.
Under all alternatives, management that restricts travel would result in adverse impacts to access and OHV use. Managing an area as limited to designated roads and trails, for example, would limit the roads and trails available for use and may adversely affect the ability to access certain areas. Restrictive travel management designations benefit values of concern for the ACEC by, for example, closing a route that may damage resources or limiting disturbances to wildlife in crucial winter ranges.
Any resource use that results in authorized or unauthorized road or trail development (e.g., oil and gas development or user-pioneered trails) can have a direct impact on paleontological resources, wildlife habitat, and other resource values because the road or trail may physically pass through or over these resources and damage or destroy them. In addition, an indirect impact from road and trail development may occur when the road provides access to a previously remote and/or inaccessible location. People who gain access may inadvertently damage fragile resources or disrupt wildlife during sensitive life stages.
Managing an area with more restrictive VRM classifications (Classes I and II) would result in adverse impacts to BLM-authorized actions that create surface disturbance or contrast with the visual setting. Adverse impacts to these BLM-authorized actions in areas with restrictive VRM classifications would result from changes to the size, scope, location, required mitigation, or BMPs for the actions. Managing an area with more restrictive VRM classifications would generally result in beneficial impacts to the important and relevant resources in an ACEC. Requiring additional design consideration and mitigation to preserve the visual setting in the area reduces the potential for facilities or development that could adversely affect important and relevant resources. Conversely, managing areas with less restrictive VRM classifications (Classes III and IV) would generally result in adverse impacts to values of concern, especially if the values of concern in an ACEC are associated with scenic quality.
Under alternatives A, B, and D, the BLM would manage the Big Cedar Ridge area (264 acres) as an ACEC; the BLM would not manage it as an ACEC under Alternative C. Paleontological resources (in the form of paleobotanical fossils of late Cretaceous age) are the values of concern in the Big Cedar Ridge area. Threats to the values of concern in this area include potential surface disturbance from mineral and ROW development, and theft and vandalism of paleontological resources.