The governing body of a local health department may employ on a full-time basis one or more registered environmental health specialists, each of whom shall be a registered environmental health specialist as provided for in this article, for the purpose of the enforcement of statutes related to public health, the regulations of the department, and any local ordinances of a local health department that relate to activities pursuant to subdivision (e) of Section 106615. However, a person who is known as an environmental health specialist trainee may be employed to work under the supervision of a registered environmental health specialist, until the trainee is qualified by examination pursuant to Section 106670, for a period that shall not exceed five years. Prior

to employment, the trainee shall have a current evaluation letter from the department stating that the education qualifications specified in Section 106660 have been met.