Cal. Pub. Res. Code § 25220

The commission may participate as a party, to the extent that it shall determine, in any proceeding before any federal or state agency having authority whatsoever to approve or disapprove any aspect of a proposed facility, receive notice from any applicant of all applications and pleadings filed subsequently by such applicants in any of such proceedings, and, by its request, receive copies of any of such subsequently filed applications and pleadings that it shall deem necessary.