39 CFR 775.14: Hearings.

(a) Public hearings must be held whenever there is:

(1) Substantial environmental controversy concerning a proposed action and a request for a hearing by any responsible individual or organization;

(2) A request for a hearing by an agency with jurisdiction over or special expertise concerning the proposed action; or

(3) A reasonable expectation that a hearing will produce significant information not likely to be obtained without a hearing.

(b) The distribution and notice requirements of §§ 775.11(d)(1) and 775.13 must be complied with whenever a hearing is to be held.