Except pursuant to RCW
43.70.740, whenever a state agency conducts a hearing which is not presided over by officials of the agency who are to render the final decision, the hearing shall be conducted by an administrative law judge assigned under this chapter. In assigning administrative law judges, the chief administrative law judge shall wherever practical (1) use personnel having expertise in the field or subject matter of the hearing, and (2) assign administrative law judges primarily to the hearings of particular agencies on a long-term basis.