Apprentice workers employed upon public works projects for whom an apprenticeship agreement has been registered and approved with the state apprenticeship council pursuant to chapter 49.04 RCW, must be paid at least the prevailing hourly rate for an apprentice of that trade. Any worker for whom an apprenticeship agreement has not been registered and approved by the state apprenticeship council shall be considered to be a fully qualified journey level worker, and, therefore, shall be paid at the prevailing hourly rate for journey level workers.