(1) If any employer fails to file a report or return required by the commissioner for the determination of combined taxes, the commissioner may make such reports or returns or cause them to be made and determine the combined taxes payable, on the basis of such information as he or she may be able to obtain, and shall collect the combined taxes as determined together with any interest thereon due under section 48-655. The commissioner shall immediately notify the employer of the assessment, in writing, by registered or certified mail, in the usual course, and such assessment shall be final unless the employer protests such assessment within fifteen days after the mailing of the notice. If the employer protests such assessment, the employer shall have an opportunity to be heard by a hearing officer upon written request therefor. After the hearing, the hearing officer shall immediately notify the employer in writing of his or her decision, and the assessment, if any, shall be final upon issuance of such notice.

(2) If any employer files a report or return required by the commissioner for the determination of combined taxes but fails to pay all or some part of the combined taxes actually due for the reported period, the commissioner may determine the combined taxes actually payable on the basis of such information as he or she may be able to obtain and shall collect the combined taxes as determined together with any interest due under section 48-655. The commissioner shall immediately notify the employer of the assessment, in writing by registered or certified mail in the usual course, and such assessment shall be final unless the employer protests such assessment within fifteen days after the mailing of the notice. If the employer protests such assessment, the employer shall have an opportunity to be heard by a hearing officer upon a written request therefor. After the hearing, the hearing officer shall immediately notify the employer in writing of his or her decision and the assessment, if any, shall be final upon issuance of such notice.

(3) Any employer or any officer or agent of an employer who fails to file a required quarterly combined tax report and wage schedule by the tenth day of the second month following the end of the calendar quarter shall pay a penalty to the commissioner of one-tenth of one percent of the total wages paid during the quarter, except that the penalty shall not be less than twenty-five nor more than two hundred dollars. For good cause shown, the commissioner may waive the penalty in accordance with rules and regulations adopted and promulgated by the commissioner. The commissioner shall remit any penalty collected to the State Treasurer who shall credit it to the pool account of the Employment Security Special Contingent Fund.