Alternative B would be the most effective for protecting the paleontological and geological values of concern in the Foster Gulch Paleontological Area. This alternative also would result in the greatest restrictions on mineral development, ROW authorizations, and other surface-disturbing activities; motorized travel; livestock grazing management; and the excavation of paleontological resources. Impacts under alternatives A and C would be similar and would allow mineral development, would open more routes to motorized travel, and would be less restrictive to the authorization of ROWs and surface disturbance in areas with paleontological resources. A portion of the Foster Gulch Paleontological Area is included in the PETM ACEC under Alternative D; the Paleocene-Eocene Thermal Maximum section describes management of and impacts to this area under Alternative D.