§ 3. Department of public service. There shall be in the state government a department of public service. The chairman of the public service commission shall be the chief executive officer of the department. He or she shall appoint and shall have the power to remove, subject to the provisions of the civil service law, all officers, clerks, inspectors, experts and employees of the department, and to approve all contracts for special service. The chairman shall designate one of the commissioners in the department or an officer of the department to act as deputy chairman during the absence or disability of the chairman and during such times such deputy chairman shall possess all the powers of the chairman as chief executive officer of the department.