T-Mobile proposes modifications/additions to telecommunications antennas and associated equipment collocated on two (2) buildings located at the following locations: 1) 3355 Mission Street, San Francisco, San Francisco County, CA 94110 (37° 44' 34.69" N, 122° 25' 16.92" W); 2) 1601 20th Street, San Francisco, San Francisco County, CA 94107; (37° 45' 35.25" N, 122° 23' 50.71" 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 these Federal undertakings or with questions on the facilities should contact Eocene, Attn: Telecommunications Department, 8951 Windsor Parkway, Johnston, IA 50131 or call 515-473-6256 (Ref. TriLA #1956/58-AM).