Time is apparently running out on Herb Miller’s grand design for a mixed-use project next to the Washington Nationals’ new stadium.

Miller, president of Western Development Corp., appears to have only days left to come up with documentation proving he’s ready to move the development forward. Mayor Anthony Williams and other city officials said this week the city is considering other options in case the project — two above-ground parking garages masked by a condominium complex, street-level retail and a boutique hotel — falls through.