If the delineated area identified is outside the CBA in a principal city, or differs from a GSA-recommended delineated area that has been developed in accordance with the guiding authorities in this part, an agency must demonstrate, in writing, that preference has been given to the CBA of a principal city or GSA's recommended delineated area, and that the agency considered the environmental and socioeconomic factors in subpart B, Location of Space, of this part. The agency justification also must address, at a minimum, the efficient performance of the mission(s) and program(s) of the agency, the nature and function of the facility or facilities involved, and the convenience of the public being served.
41 C.F.R. §§102-83.130