The purpose of the Department of Health Act is to establish a single, unified department to administer the laws and exercise the functions relating to health formerly administered and exercised by various organizational units of state government, including the state health agency, the scientific laboratory system and an appropriate allocation of administrative support services of the health and social services department and the hospital and institutions department. All public health and scientific laboratory functions formerly performed by the health and environment department shall be performed by the department. Behavioral health services, including mental health and substance abuse services, provided by or through the department shall be subject to the direction of the secretary and the provisions of Section 9-7-6.4 N.M. Stat. Ann..