; and (7) any other modifications the Administrator considers necessary within the stated environmental objectives of the National Environmental Policy Act of 1969 ( 42 U.S.C. 4321 et seq. ) and the Federal priority to maintain global leadership in aviation innovation. (b) Briefing No later than 90 days after the date of enactment of this Act, the Administrator shall brief the Committee on Transportation and Infrastructure of the House of Representatives and the Committee on Commerce, Science, and Transportation of the Senate on the plan of the Administration to implement subsection (b), including each of the considerations specified in the subsection, and an explanation for any consideration the Administrator does not intend to implement. (c) Concurrent reviews If the Administrator determines that the review of an unmanned aircraft system’s design, construction, maintenance and operational sustainability, airworthiness approval, or operational approval requires environmental assessment, including requirements under the National Environmental Policy Act of 1969 ( 42 U.S.C. 4321 et seq. ), the Administrator shall, to the maximum extent practicable, conduct such reviews and analyses concurrent with one another. (d) Rule of construction Nothing in this section shall be construed as prohibiting, restricting or otherwise limiting the authority of the Secretary of Transportation or the Administrator from implementing or complying with the requirements of the National Environmental Policy Act of 1969 ( 42 U.S.C. 4321 et seq. ) and any related requirements to ensure the protection of the environment and aviation safety. (e) Associated UAS certification standards (1) In general The Administrator shall develop and establish substantive criteria and standards metrics used by the Administrator to determine whether to approve or disapprove the airworthiness of an unmanned aircraft pursuant to part 36 of title 14, Code of Federal Regulations. (2) Substantive criteria and standards metrics In establishing the substantive