18 CFR 385.904 - Commencement of proceeding (Rule 904).
(a) Except as provided in paragraph (b) of this section, the proceeding pursuant to this subpart will be commenced by filing with the Secretary of the Commission either an answer by a petitioner pursuant to Rule 906(b)(1), or a written notice by the Secretary that a petitioner has filed a notice of intent to contest an order reviewable under this subpart, whichever is filed first. The Secretary must file written notice that a petitioner has filed a notice of intent to contest an order reviewable under this subpart within 15 days of the Secretary's receipt of such notice of intent. When the Secretary files the written notice, the Secretary must serve a copy of the contested order upon other participants in the prior proceedings and upon persons denied intervention in the prior proceedings, and must certify to the Commission that such service has been made, stating the names and addresses of persons served.
(b) The proceeding pursuant to this subpart with respect to an interim remedial order for immediate compliance will be commenced by a petitioner's filing with the Secretary of the Commission, for the Commission, and serving on other participants in the prior proceedings, if any, a notice of petition for review of an interim remedial order for immediate compliance pursuant to 10 CFR 205.199D(i)(1) (interim remedial order of immediate compliance). The Commission will defer consideration of the merits of the order until a final remedial order is issued by the Secretary.
(c) Upon commencement of a proceeding, the Commission or its designee will designate a presiding officer for the proceeding, and the Commission or its designee will notify participants in the prior proceedings and persons denied intervention in the prior proceedings of such designation.