; (ii) flood control; (iii) navigation; (iv) water supply; and (v) air quality and the preservation of other aspects of environmental quality. (B) Information from other agencies In preparing a written statement under subparagraph (A), the head of a Federal agency may make use of information produced or made available by other agencies with relevant expertise in the factors described in clauses (i) through (v) of that subparagraph. (f) Conditions The Secretary of Agriculture shall not delegate the authority to require a condition under section 4(e), other than to the Chief of the Forest Service or the Under Secretary for Natural Resources and Environment. (g) Interagency communications (1) In general Interagency cooperation in the preparation of environmental documents under the National Environmental Policy Act of 1969 ( 42 U.S.C. 4321 et seq.) and interagency communications relating to licensing process coordination under this section shall not— (A) be considered to be ex parte communications under Commission rules; or (B) preclude an agency from participating in a licensing proceeding under this part. (2) Separation of staff Notwithstanding paragraph (1), to the extent the Commission determines necessary, the Commission may require Federal and State agencies participating as cooperating agencies under the National Environmental Policy Act of 1969 ( 42 U.S.C. 4321 et seq.) to demonstrate a separation of staff cooperating with the Commission and staff that may participate in an intervention in the applicable proceeding under this part. 36. Trial-type hearings (a) Definition of covered measure In this section, the term covered measure means— (1) a condition prescribed under section 4(e), including an alternative condition proposed under section 33(a); (2) fishways prescribed under section 18, including an alternative prescription proposed under section 33(b)