The department shall
(1) accept all minors committed to the custody of the department and all minors who are involved in a written agreement under AS 47.14.100(c), and provide for the welfare, control, care, custody, and placement of these minors in accordance with this chapter;
(2) require and collect statistics on juvenile offenses and offenders in the state;
(3) conduct studies and prepare findings and recommendations on the need, number, type, construction, maintenance, and operating costs of juvenile homes, work camps, facilities, and the other institutions, and adopt and submit a plan for construction of the homes, work camps, facilities, and institutions when needed, together with a plan for financing the construction programs;
(4) examine, where possible, all facilities, institutions, work camps, and places of juvenile detention in the state and inquire into their methods and the management of juveniles in them.