T-Mobile is proposing modifications and additions to telecommunications antennas and associated equipment collocated on a building located at an address 311 California Street, San Francisco, San Francisco County, CA 94104 (Latitude 37° 47' 34.89" N, Longitude 122° 24' 00.81 W). Eocene Environmental Group is publishing this notice in accordance with Federal Communications Commission regulations (47 CFR § 1.1307) for Section 106 of the National Historic Preservation Act (NHPA) and for the National Environmental Policy Act (NEPA). Parties interested in commenting on this Federal undertaking or with questions on the facility should contact Eocene, Attn: Telecommunications Department, 8951 Windsor Parkway, Johnston, IA 50131 or call 515-473-6256 (Ref. TriLA #2233-AM)