18 CFR § 380.10 - Participation in Commission proceedings.
(a) Intervention proceedings involving a party or parties - 1) Motion to intervene.
(i) In addition to submitting comments on the NEPA process and NEPA related documents, any person may file a motion to intervene in a Commission proceeding dealing with environmental issues under the terms of § 385.214 of this chapter. Any person who files a motion to intervene on the basis of a draft environmental impact statement will be deemed to have filed a timely motion, in accordance with § 385.214, as long as the motion is filed within the comment period for the draft environmental impact statement.
(ii) Any person that is granted intervention after petitioning becomes a party to the proceeding and accepts the record as developed by the parties as of the time that intervention is granted.
(i) Issues not set for trial-type hearing. An intervenor who takes a position on any environmental issue that has not yet been set for hearing must file a timely motion with the Secretary containing an analysis of its position on such issue and specifying any differences with the position of Commission staff or an applicant upon which the intervenor wishes to be heard at a hearing.
(ii) Issues set for trial-type hearing.
(A) Any intervenor that takes a position on an environmental issue set for hearing may offer evidence for the record in support of such position and otherwise participate in accordance with the Commission's Rules of Practice and Procedure. Any intervenor must specify any differences from the staff's and the applicant's positions.
(B) To be considered, any facts or opinions on an environmental issue set for hearing must be admitted into evidence and made part of the record of the proceeding.
(iii) Commission pre-filing activities commenced under §§ 157.21 and 50.5 of this chapter, respectively, are not considered proceedings under part 385 of this chapter and are not open to motions to intervene. Once an application is filed under part 157 subpart A or part 50 of this chapter, any person may file a motion to intervene in accordance with §§ 157.10 or 50.10 of this chapter or in accordance with this section.
(b) Rulemaking proceedings. Any person may file comments on any environmental issue in a rulemaking proceeding.