(a) Hearings granted under § 66.53 shall be held as provided in subpart J.

(b) The Presiding Officer at a hearing granted under § 66.53 shall issue an initial decision within ninety days after the Administrator grants the hearing, unless the duration of the hearing or the deadline for decision is extended by the Presiding Officer upon agreement of the parties. Failure to issue a decision (whether or not by consent) within 90 days shall not affect the validity of the proceedings or the accrual of penalties in any manner.