The department shall establish by rule and regulation a cost based reimbursement system to pay providers of services and supplies under home and community based waiver programs for persons with developmental disabilities or acquired brain injury. The department shall apply to the center for Medicare and Medicaid services of the United States department of health and human services for authorization to reimburse at an enhanced rate direct care providers who have training and certification as behavioral specialists in the care of persons dually diagnosed with a developmental disability and a mental illness.