(a) Upon receipt of a timely request for a hearing under § 23.510 (where the Administrator has determined that relevant facts are in dispute) or § 23.520 (debarment), the Administrator shall refer the case to the Chief Administrative Law Judge by Order of Reference, to which shall be attached a copy of the investigative findings letter from the Administrator and response thereto, for designation of an Administrative Law Judge to conduct such hearings as may be necessary to decide the disputed matters. A copy of the Order of Reference and attachments thereto shall be served upon the respondent. The investigative findings letter from the Administrator and response thereto shall be given the effect of a complaint and answer, respectively, for purposes of the administrative proceedings.

(b) At any time prior to the closing of the hearing record, the complaint (investigative findings letter) or answer (response) may be amended with the permission of the Administrative Law Judge and upon such terms as he/she may approve. For proceedings pursuant to § 23.510, such an amendment may include a statement that debarment action is warranted under § 23.520. Such amendments shall be allowed when justice and the presentation of the merits are served thereby, provided there is no prejudice to the objecting party's presentation on the merits. When issues not raised by the pleadings are reasonably within the scope of the original complaint and are tried by express or implied consent of the parties, they shall be treated in all respects as if they had been raised in the pleadings, and such amendments may be made as necessary to make them conform to the evidence. The presiding Administrative Law Judge may, upon reasonable notice and upon such terms as are just, permit supplemental pleadings setting forth transactions, occurrences or events which have happened since the date of the pleadings and which are relevant to any of the issues involved. A continuance in the hearing may be granted or the record left open to enable the new allegations to be addressed.