47 CFR § 27.903 - Coordination requirements.
(a) The licensee in the 1670-1675 MHz band will be issued a geographic area license on a nationwide basis in accordance with § 27.6(f).
(1) That requires submission of an Environmental Assessment under part 1, § 1.1307 of this chapter;
(2) That requires international coordination;
(3) That operates in areas listed under part 1, § 1.924 of this chapter.
(d) Prior to construction of a station, a licensee must register with the Commission any station antenna structure for which notification to the Federal Aviation Administration is required by part 17 of this chapter.
(e) It is the licensee's responsibility to determine whether an individual station requires referral to the Commission.