(a) Whenever DSOD or the department is required to serve documents on a dam owner under the provisions of this article, the dam owner shall be served by using at least one of the following methods:

(b) If, after the exercise of reasonable diligence, service cannot be achieved pursuant to subsections (a)(1)--(a)(3), then service may be made by leaving the document at the residence or business of the person named to be served, or at the physical location of the dam that is the subject of the document being served, with a person not less than 18 years of age. Where service is made in this manner, the proof of service shall also state the date and place of delivery and the name of the person to whom the documents were given. Where the person making the service is unable to obtain the name of the person to whom the documents were given, the person making the service may substitute a physical description for the name.