(a) Any person aggrieved by a final order of the department granting or denying in whole or in part the relief sought may obtain a review of such order by filing in a court of competent jurisdiction, within 30 days of its issuance, a written petition praying that such decision of the department be modified or set aside.
(b) No objection that has not been urged before the department shall be considered by the court unless the failure or neglect to urge such objection is excused because of extraordinary circumstances. The findings of the department, as to the facts, if supported by substantial evidence, shall be conclusive.