Upon the return day of such notice, the person so notified shall
file with the Board a written statement setting forth the position
of the persons so notified, the answer, if any, to the charges made
against him, the methods, practices and procedures, if any, which
are being taken to correct each alleged violation and any other defenses
or information pertinent to the case. Pertinent and relevant testimony
of witnesses shall be received in support of or opposition to said
statement. Failure to file a statement shall be treated as a default
in appearance.