50 C.F.R. § 29.21
Compatible use means a proposed or existing wildlife-dependent recreational use or any other use of a national wildlife refuge that, based on sound professional judgment, will not materially interfere with or detract from the fulfillment of the National Wildlife Refuge System mission or the purposes of the national wildlife refuge. The term "inconsistent" in section 28(b)(1) of the Mineral Leasing Act of 1920 (30 U.S.C. 185 ) means a use that is not compatible.
Department means U.S. Department of the Interior unless otherwise specified.
National Wildlife Refuge System land means lands and waters, or interests therein, administered by the Secretary as wildlife refuges, areas for the protection and conservation of fish and wildlife that are threatened with extinction, wildlife ranges, game ranges, wildlife management areas, or waterfowl production areas.
Other lands means all other lands, or interests therein, and waters administered by the Secretary through the U.S. Fish and Wildlife Service which are not included in National Wildlife Refuge System lands, e.g., administrative sites, research stations, fish hatcheries, and fishery research stations.
Project Manager means the officer in charge of the land under administration by the U.S. Fish and Wildlife Service.
50 C.F.R. §29.21