Neb. Rev. Stat. §§ 71-5310.01
Except as otherwise expressly provided, any notice, order, or other instrument issued by or under authority of the director under the Nebraska Safe Drinking Water Act may be served on any person affected by such notice, order, or other instrument, personally or by publication, and proof of such service may be made in like manner as in case of service of a summons in a civil action, such proof to be filed in the office of the department, or such service may be made by mailing a copy of the notice, order, or other instrument by certified or registered mail directed to the person affected at his or her last-known post office address as shown by the files or records of the department, and proof of service may be made by the affidavit of the person who did the mailing and filed in the office of the department.
Every certificate or affidavit of service made and filed as provided in this section shall be prima facie evidence of the facts stated in such certificate or affidavit, and a certified copy shall have like force and effect.
Neb. Rev. Stat. §§ 71-5310.01